cultura e scienza del colore color culture and science 79 cultura e scienza del colore color culture and science | 09 | 2018 issn 2384-9568 this page has been intentionally left white claudio oleri memorial the associazione italiana colore, with all its members would like to express its deepest condolences for the premature death of claudio oleari on 23 january 2018, together with all who have known him, read his books, listened to his conferences or lectures. he was an eminent physics scholar and an associate professor at the university of parma, at the department of physics and earth sciences. he dedicated his life to the activities of teaching with the same passion and interest that he dedicated to the researches in the context of colour, applying physics to perception and fixing its role in colorimetry. moreover in 1995 he started the gruppo in colorimetria e reflectoscopia which later became the associazione italiana colore. his availability for colleagues and students and his ability to listen and advice are proverbial: his kindness will be always remembered by everyone who has known him. these qualities are clearly demonstrated by the message of his profile at the university of parma “my office is at the department of physics (campus, viale usberti 7/a), phone 0521-905214, email address: claudio.oleari@fis.unipr.it. you can send me email for any request or question related to my course. i’m almost always in my office and i’m always available except when otherwise busy. just call to check if i’m busy. i always reply to emails.” he conducted within the italian association, a valuable activity of information and connection of which remains a rich bibliography, always having in mind the need to invest in research and training both in italy and abroad. his death leaves a void difficult to fill and the world of colour loses an intellectual and an attentive and informed scholar. gruppo del colore – associazione italiana colore cultura e scienza del colore color culture and science 60 cultura e scienza del colore color culture and science | 04/15 nel 1° capitolo causse, cercando di semplificare al massimo la comprensione degli aspetti più ostici, affronta un ventaglio ricco e complesso di questioni che riguardano il colore l’incipit recita con tono confidenziale: “a costo di darvi una delusione, vi informo che il colore non esiste!” e prosegue sostenendo che se le teorie contemporanee sulla luce intesa come trasferimento di energia (fascio di fotoni) si sono affermate da poco è perché “c’è chi non ha avuto abbastanza coraggio si mandare in pensione l’amico goethe”. con esempi accattivanti (perché le nuvole appaiono bianche, il cielo azzurro e il sole rosso all’orizzonte) conduce il lettore a comprendere alcuni aspetti della fisica, della percezione, della temperatura di colore, della sinestesia e della riproduzione, ma anche della percezione dei colori nella fauna e nella flora. nel 2° capitolo l’autore dimostra come i colori influenzino le facoltà e i comportamenti umani, assorbito dalla retina ma anche dalla pelle, incidendo sull’umore, il bioritmo, l’udito, la recensioni jean-gabriel causse, lo stupefacente potere dei colori ponte alle grazie, milano, 2015 l’editore ponte alle grazie (marchio di adriano salani editore) dopo il successo ottenuto dalla pubblicazione dei libri sul colore di pastoureau promuove un altro libro sul colore e scritto dal francese jean-gabriel causse, color designer membro del comité français de la couleur di parigi, che è già stato tradotto in 19 lingue. un libro agile, senza illustrazioni, scritto in tono colloquiale rivolgendosi direttamente al lettore, ricco di aneddoti e di ‘consigli’. il titolo stesso indica il focus dello scritto: stupire il lettore avvicinandolo alle numerose proprietà dei colori di influenzare la nostra vita personale e collettiva, fatto che nonostante sia ormai scientificamente provato rimane molto sottovalutato. recensioni a cura di renata pompas 6104/15 | cultura e scienza del colore color culture and science a cura di renata pompas recensioni memoria, l’emotività e altro. gli esempi variano dalla neurofisiologia all’etologia, dal suo uso nella pubblicità, ai suoi effetti sul gusto, l’olfatto, il packaging, la vendita, sulle prestazioni degli sportivi, il rendimento degli scolari, la condotta dei carcerati: sarebbe stato infatti dimostrato che le celle dipinte di rosa nel centro correzionale della marina americana di seattle sono state in grado di ridurre l’aggressività dei detenuti dopo soli quindici minuti di esposizione. inoltre, un paragrafo è dedicato ai “colori sessuali” perché, come recita l’aletta della copertina, “sapevate che la frequenza dei rapporti sessuali è maggiore all’interno di una stanza a dominante rossa invece che grigia?”. e sebbene il colore preferito in tutto il mondo sia il blu e quello che genera unanime ostilità sia il giallo, casse suggerisce di ascoltare istintivamente qual è il nostro colore preferito per trarne benessere: raccomandazione consigliata da un color designer che progetta cartelle tendenze colore e che ne mostra un’apertura notevole. un altro paragrafo è dedicato all’importanza della luce e al suo rapporto con la melatonina, infine il capitolo si conclude con un accorato richiamo alle proprietà curative della cromoterapia. nel 3° capitolo si trovano i consigli, suffragati di esempi e riferimenti, sulla scelta dei colori nella moda e nell’arredamento in relazione alla loro simbologia e all’apporto del feng shui, suddivisi colore per colore: blu, rosso, rosa, verde, nero, grigio, bianco, viola, giallo, arancione e bruno/marrone/beige e turchese che, come scrive l’autore, “già cinquemilacinquecento anni prima di cristo era un colore chic”. nelle conclusioni causse scrive che “il colore è indispensabile alla nostra vita, eppure non è mai stato così poco presente accanto a noi, sia sui nostri abiti che nelle nostre case, come lo è oggi. in quale misura un simile grigiore si può ritenere responsabile del basso morale degli occidentali? è difficile da stabilire. io tuttavia sono persuaso che i graffiti colorati nelle periferie grigie siano opera di ragazzi che inconsapevolmente provano il bisogno viscerale di uscire da questa cupezza (…) come ha detto l’umorista pierre dac: se la materia grigia fosse più rosa, il mondo avrebbe meno idee nere”. nella appendice causse confronta le simbologie dei colori nel mondo, colore per colore, tratte da: goethe, kandinsky, pastoureau, grossman e wisenblit, dizionario teologico di elwell, école polytechnique di montréal, trattati di feng shui e di medicina ayurvedica. da ultimo le ventidue pagine dedicate alle fonti legittimano il tono leggero e divertente del libro. cultura e scienza del colore color culture and science 03 15 riv is ta s em es tr al e | h al fye ar ly jo ur na l rivista dell’associazione italiana colore www.gruppodelcolore.it cultura e scienza del colore color culture and science http://www.gruppodelcolore.it cultura e scienza del colore color culture and science rivista dell’associazione italiana colore http://jcolore.gruppodelcolore.it/ issn 2384-9568 direttore responsabile | editor-in-chief maurizio rossi vicedirettore | deputy editor davide gadia comitato scientifico | scientific committee john barbur (city university london, uk) berit bergstrom (ncs colour ab, se) giulio bertagna (b&b colordesign, it) aldo bottoli (b&b colordesign, it) patrick callet (école centrale paris, fr) jean-luc capron (université catholique de louvain, be) elizabeth condemine (couleur & marketing paris, fr) osvaldo da pos (università degli studi di padova, it) bepi de mario (crasmi, it) hélène declermont-gallernade (chanel parfum beauté, fr) christine fernandez-maloigne (university of poitiers, fr) renato figini (konica-minolta, eu) davide gadia (università degli studi di milano, it) robert hirschler (serviço nacional de aprendizagem industrial, br) francisco imai (canon, usa) lia luzzatto (color and colors, it) kevin mansfield (ucl, uk) veronica marchiafava (ifac-cnr, it) gabriel marcu (apple, usa) manuel melgosa (universidad de granada, es) annie mollard-desfour (cnrs, fr) claudio oleari (università degli studi di parma, it) laurence pauliac (historienne de l’art et de l’architecture, paris, fr) marcello picollo (ifac-cnr, it) renata pompas (afol milano-moda, it) boris pretzel (victoria & albert museum, uk) noel richard (university of poitiers, fr) katia ripamonti (cambridge research system, uk) alessandro rizzi (università degli studi di milano, it) maurizio rossi (politecnico di milano, it) jodi l. sandford (università di perugia, it) raimondo schettini (università degli studi di milano bicocca, it) gabriele simone (st microelectronics, it) andrea siniscalco (politecnico di milano, it) ferenc szabó (university of pannonia, hu) francesca valan (studio valan, it) ralf weber (technische universität dresden, de) alexander wilkie (charles university in prague, cz) collaboratori | contributors nicola agresta, maria francesca alberghina, natalia alekseeva, rosita barraco, laura bellia, fabio bisegna, maria brai, giulia brun, chiara burattini, alessandra cirafici, michele emmer, marta fibiani, marco gargano, franco gugliermetti, roberto lo scalzo, nicola ludwig, mario marchetti, giuseppe mennella, annalisa moneta, davide pandini, lorella pellegrino, renata pompas, fernanda prestileo, luigi rossi, giuseppe l. rotino, vincenzo paolo senese, salvatore schiavone, andrea siniscalco, gennaro spada, laura toppino, luigi tranchina redazione | editorial staff aldo bottoli, daria casciani, davide gadia, veronica marchiafava, francesca valan editore | publisher gruppo del colore – associazione italiana colore www.gruppodelcolore.it 03numero 03 maggio 2015 number 03 may 2015 gruppo del colore associazione italiana colore cultura e scienza del colore color culture and science rivista dell’associazione italiana colore registrazione presso il tribunale di milano al n. 233 del 24.06.2014 http://jcolore.gruppodelcolore.it/ http://www.gruppodelcolore.it sommario | summary italiano english recensioni 03 4 12 18 24 28 33 40 45 51 56didactics impiego della principal component analisys per l’analisi statistica su dati colorimetrici di tessere musive pavimentali di maria francesca alberghina, rosita barraco, maria brai, lorella pellegrino, fernanda prestileo, salvatore schiavone, luigi tranchina il ruolo del colore nel progetto di un modulo abitativo per la stazione spaziale internazionale di chiara burattini, franco gugliermetti, mario marchetti, fabio bisegna metodologie per lo studio di miscele di pigmenti pittorici con spettrometria a fibra ottica di davide pandini, nicola ludwig, marco gargano, annalisa moneta manlio brusatin, verde. storie di un colore, biblioteca marsilio, venezia, 2013 michel pastoureau, verde. storia di un colore, adriano salani editore, milano, 2013 a cura di renata pompas colours and soap bubbles by michele emmer interaction of color scheme and noise in the metro interior. multisensory evaluation and subjective testing by natalia alekseeva, alessandra cirafici, vincenzo paolo senese pigment variation by colorimetric analysis in raw, grilled and boiled eggplant (solanum melongena l.) fruits by marta fibiani, giuseppe l. rotino, laura toppino, giuseppe mennella, roberto lo scalzo measured color changes under fluorescent and led lamps by laura bellia, nicola agresta, luigi rossi, gennaro spada de coloribus: new perspectives on a series of recipes for making pigments within the compositionens lucenses tradition by giulia brun didactic for building professionals. the experience of lighting design and color design masters by andrea siniscalco 98 color culture and science journal vol. 11 (2) book review: nature & colour new perspectives on dyeing. renata pompas ennia visentin: nature & colour new perspectives on dyeing. “lis aganis” eco museum of the friulian dolomites. maniago (pn), 2019. (pages 156). ennia visentin is an expert in mural decoration, lecturer in pictorial decoration techniques and fresco, with a series of exhibitions to her credit. inspired by the renowned and seminal book by franco brunello (the art of dyeing in the history of mankind) in recent years she has devoted herself to the study of coloring substances used in natural dyes, the outcomes of which are described in this book. a very interesting book that combines the theoretical activity of study and research on primary sources described in ancient and contemporary texts, with accurate validation in the lab, documented by color slides inserted in the text. an in-depth description of dyeing and its procedures is followed by a section which deals with a very current theme: the possibility of a new ethical-cultural paradigm, for an aware consumption of non-toxic and renewable materials, recovery and use of waste material. part one – the art of dyeing a concise description of the main and most relevant natural dyes used from prehistory to current times, which provides a comprehensive historical view, mostly within a european context. part two – dyeing processes this is the most substantial section of the book which, beginning with the textile fibers and their preparation handling, describes the process of gathering and drying of plants, the different types of color dips and their final fixation. direct dyeing, by immersion in water of the dye vegetable and of the untreated textile fibers. mordant dyeing, by immersion in water of the dye plant and of the textile fibre treated with processing substances and additives. single dip dyeing, in which mordanting and dyeing take place together. layered dyeing, a vegetal print currently termed “eco-print”. multiple layer dyeing, through successive color dips, interposed by setting and drying of the fibers. dyeing below boiling point, which enhances particularly some colors. cold dip dyeing, which requires an extended processing time. solar dyeing, which uses rainwater and exposure to the sun. these are the two topmost eco-sustainable processes. fermentation dyeing, which is done by macerating fruits or lichens in water with alkaline substances. different dyes with the same dip, with the same plant, with different ph: relative to different immersions of fibers in the same dyeing vat, with results that decrease down to the dullest shades of the last dip. process used in antiquity to dye the people’s cloth in the same dyeing bath used for more precious fabrics. combination dyeing, where she demonstrates how the most vibrant greens have always been obtained combining two coloring substances. developed dyes, obtained by employing metallic salts. paint dyeing, which entails an initial process of painting, followed by drying and then dyeing. vat dyeing, process by which fibers and fabrics immersed in the dyebath take on their colouration only through exposure to air (oxidation), used in blue and purple dyeing. part three – dye plants a selection of the main plants used for the ranges of reds, yellows, blues, of greens, browns, of blacks and intermediate shades obtained through combinations of colourants. part four – when nature becomes art: dye plants and dye recipes in this section, contextualising them with historical notes, she describes the plant, the extraction of pigment and 99 color culture and science journal vol. 11 (2) dye recipes of madder (rubia tinctorum) for reds, of wild mignonette (reseda lutea) for yellows, of woad (isatis tinctoria) and indigo (indigofera tinctoria) for blues. part five – toward a new ethical-cultural paradigm this section, in which ennia visentin points out how the textile sector is considered the second most polluting in the world, seemed to me very new and worthy of note. she deals with the issue not only of developing natural dyes on eco-demo compatible fibers able to guarantee salubrity characteristics, but also with the recovery of marginal lands for cultivation and the reutilisation of waste products or by-products from the agricultural or agri-food sectors, a research program has been carried out on “local dye woods”, intended as being part of the friulian region that supported her project: among other items the waste material from tree and shrub prunings were analysed and the dyeing with branches, bark and shavings or various scraps of walnut wood, cultivated and wild apple and fig, of which she provides recipes. in conclusion the author hopes to succeed through her research in connecting single agricultural enterprise with artisan and tourist ventures, from the viewpoint of a circular economy, which forges a cultural product model and attention to social inclusion. the bibliography concludes the work. cultura e scienza del colore color culture and science 4501/14 | cultura e scienza del colore color culture and science il concetto di hillman riguardo ai colori è che “dal punto di vista culturale non sono qualità secondarie, riconducibili a sensazioni fisiologiche del sistema nervoso di un soggetto percipiente, ma sono il mondo stesso. rappresentano cioè la realtà fenomenica del mondo, il modo in cui il mondo manifesta se stesso e, in quanto agenti operanti nel mondo, ne sono i principi formativi primari”. la differenziazione archetipa in contrasto con il consueto modo di vedere i colori derivato dalla filosofia occidentale di newton, locke, berkeley e kant che ritenevano che i colori non fossero inerenti agli oggetti, bensì qualità secondarie dovute all’azione della luce sulla nostra vista soggettiva l’alchimia ritiene che i mutamenti dei colori rivelano il mutamento dell’esistenza. hillman applica questo concetto alla psiche: 1. introduzione nel 2010 james hillman (1926 – 2011), quasi 60 dopo psicologia e alchimia di gustav jung, ha presentato la sua versione riguardo le corrispondenze tra gli stadi e i colori dell’opus alchemico e i momenti dell’opus analitico in: psicologia alchemica, (edizione italiana con traduzione di adriana bottini per adelphi edizioni, milano, 2013). hillman è stato un intellettuale di indiscussa fama e cultura, allievo di jung ha diretto lo ‘jung institut’ di zurigo, è stato professore nelle maggiori università americane, conferenziere e saggista, ha fondato la cosiddetta ‘psicologia archetipica’. in questo libro hillman ha radunato e collegato numerosi lavori, articoli e testi di conferenze sull’argomento, sviluppati tra tra il 1968 e il 2004, al fine di dimostrare che il linguaggio alchemico è “una modalità di terapia, è terapia in sè”. a cura di renata pompas recensioni james hillman, psicologia alchemica. adelphi edizioni, milano, 2013. 46 cultura e scienza del colore color culture and science | 01/14 “i colori sono un primario modo di presentarsi della differenziazione archetipa, ciascun colore una celebrazione della sensualità del cosmo, ciascuna sfumatura e tonalità capace di tingere la psiche con una particolare gamma di umori e di legarla al mondi attraverso particolari affinità. umori e affinità che diventano il nostro gusto, le nostre avversioni e passioni”. nigredo (nero), albedo (bianco) e rubedo (rosso) sono i tre colori principali dell’opus alchemico a cui hillman aggiunge la citrinitas (giallo), presente nei testi fino al xvi secolo e poi soppresso, e il blu a cui dedica molte pagine. bianco sale curiosamente non esordisce con la fase della nigredo, con cui inizia ogni trattato di alchimia, ma con un certo tipo di bianco che chiama “la sofferenza del sale”, un bianco inteso come fissazione, stato fisico e mentale da sciogliere, massa confusa metafora dei momenti iniziali del processo psichico, in cui tutto è ancora incerto e passivo. nero dissolvente quindi affronta il nero: “la metafora dello stato depressivo, confuso, pessimista, dell’informe, del pensiero negativo, amato da tutti i non conformisti che poi rimangono intrappolati nella loro identificazione con il nero, colore inflessibile, ostinato e fondamentalista”. a queste considerazioni aggiunge l’avvertenza che la nigredo è fondamentale, perché provoca quella dissoluzione che rende possibile il cambiamento psicologico. blu immaginativo tra il nero e il bianco inserisce il blu, in cui la disposizione esistenziale depressiva del nero si scioglie in tristezza; colore puritano e malinconico, della sobrietà e della saggezza, che rappresenta l’immaginazione. bianco argento la fase al bianco, albedo, descrive il secondo tipo di bianco, quello connesso all’argento alchemico, corrispondente simbolicamente al cervello (così come l’oro corrisponde al cuore): colore della luna e della follia (in inglese lunacy), della riflessione e della parola. in analisi significa “parlare di ciò che sta avvenendo ora” e rappresenta la transizione dalla fantasia passiva all’immaginazione attiva. giallo conoscenza la fase al giallo, citrinitas, manifesta: “il procedere del tempo, quando le cose si corrompono marciscono, si decompongono; è un colore caldo, maleodorante, maschile, attivo. nell’analisi (psicoanalitica) introduce il dolore della conoscenza e la complicazione delle emozioni”; mentre inteso come oro esprime sentimenti di bontà, integrità, gioia, realizzazione. 4701/14 | cultura e scienza del colore color culture and science centralità del percorso hillman volutamente non giunge alla fase al rosso, la rubedo, il lapis, fase finale dell’opus, che è rossa; krasnyy, come dicono i russi in una unica parola che significa ‘rosso’ e ‘bello’. infatti dal suo punto di vista “l’importante non è la meta ma è il percorso”, benché citi jung per il quale la rubedo rappresenta un’attività libidica, un movimento “nella parte infrarossa dello spettro archetipo, dove prevale l’istinto”. al termine dell’analisi delle fasi alchemiche e dei loro colori hillman afferma che ciascuna fase è separabile e indipendente da una sequenza temporale, e che la meta è immaginaria e mitica, fuori dal tempo, significativa solo per indirizzare il percorso. in conclusione è un libro appassionato e denso, un erudito concentrato di informazioni, citazioni, rimandi e connessioni, con un ricco apparato di note. a mio parere di non facile lettura, sia per l’argomento, sia per lo stile iperbolico della scrittura, che l’autore adotta per un nuovo metodo psicologico basato sulla “narrazione di storie…amplificandone il volume con somiglianze, parallelismi, analogie”, un somma faticosa di brani e riferimenti scelti “per invitare, sedurre, ammaliare, esaltare e convincere con l’arte della retorica, a volte, con la poesia”. cultura e scienza del colore color culture and science 6102/14 | cultura e scienza del colore color culture and science ‘scrivere con la luce’ è il titolo della trilogia, pubblicata da electa, che vittorio storaro, tre volte premio oscar per la fotografia, ha dedicato alla luce, al colore e agli elementi. un insieme di testi ricchi di spunti e di riflessioni che corredati da un apparato iconografico splendido e sontuoso, sondano i misteri della visione, attraverso l’ esperienza personale, maturata in tanti anni di lavoro e di vita, e quella catturata nei testi dei filosofi, nelle teorie degli scienziati, nelle opere dei pittori, negli scatti della fotografia dove luce e oscurità si relativizzano e, uscendo dall’assolutezza senza luogo dell’inizio del tempo, diventano oggetti di percezione, generando nel loro dialogo, colori, ombre e forme. ed è ancora la luce che torna con i suoi aspetti simbolici a raccontare la storia dei fori imperiali nel progetto per la loro illuminazione affidatogli dal comune di roma e realizzato insieme a sua figlia francesca storaro, affermata architetto e lighting designer; l’obiettivo era quello di realizzare un impianto di illuminazione artistica permanente della porzione iniziale dei fori: il foro di augusto, il foro di nerva e il foro traiano. l’intuizione creativa di storaro, nominato ambasciatore dell’immagine di roma sua città natale, si fonda come sempre sul rapporto tra luce e colore: legame fisico ed emozionale inscindibile. attraverso il suo sguardo si accendono i riflettori su 150 anni di storia del glorioso impero romano, scanditi dalla modulazione della luce che crea un ponte tra passato e presente, rendendo eterna la materia antica. nella presentazione avvenuta il 16 settembre 2014 con la partecipazione delle autorità cittadine, vittorio storaro ha narrato in campidoglio, con un trasporto quieto e coinvolgente, il progetto luministico che percorre la gloria della civiltà romana e si rende palpabile attraverso un uso sapiente e consapevole della luce che, innalzandosi dalla terra al cielo, scende nuovamente in modo diffuso a simboleggiare la “pax romana’’ che unifica i territori. la forza del progetto sta nel non aver isolato e messo in risalto soltanto i monumenti principali, ma di aver coinvolto anche i fondali come attori non protagonisti, essenziali e decisivi per le suggestioni d’insieme. la luce non è drammatica o enfatica ma morbida, soffice e soffusa per generare stupore e compiacimento. il foro di augusto la divina gloria di roma dell’epoca augustiana, fondamento di civiltà, di pace, di prosperità e di abbondanza è alla base della simbologia illuministica di questo foro. la luce è pensata come l’onda della saggezza e della conoscenza che sale dai gradini del tempio di marte ultore, con una grande intensità luminosa, si espande nell’area circostante attenuandosi e arriva ad abbracciare, con toni lunari, neutri, morbidi e uniformi, tutto il perimetro della muraglia che lo circoscrive. (figura 1) il foro di nerva cambia l’ispirazione storica e cambia la qualità e la direzione delle luci. per questo foro, che ha segnato la transizione tra due imperatori domiziano e nerva, le luci orientate dal basso verso l’alto si concentrano nel luogo dove sorgeva il tempio di minerva. al di sopra della linea muraria una seconda serie di luci, caratterizzate dalla stessa unitarietà illuministica, diffonde il suo chiarore in modo uniforme sul a cura di daniela de biase lia luzzatto recensioni scrivere con la luce 62 cultura e scienza del colore color culture and science | 02/14 figura 1 ideazione luministica del foro di augusto figura 2 ideazione luministica del foro di nerva figura 3 ideazione luministica del foro di traiano 6302/14 | cultura e scienza del colore color culture and science suolo al centro del foro. (figura 2) il foro di traiano le luci si concentrano sulla colonna traiana, voluta dall’imperatore per celebrare la vittoria sui daci e rende leggibile il racconto delle sue epiche gesta, scolpito nei rilievi che si sviluppano in modo elicoidale dalla base alla sommità. la colonna viene così ad essere un centro di luminosità che si irradia nello spazio a lei vicino. altre fonti luminose, orientate dal basso verso l’alto, fanno sorgere dall’oscurità le colonne parallele che determinano la basilica ulpia la cui pavimentazione si giova della luce circostante e di quella di una serie di proiettori. (figura 3) in un’intervista rilasciata al sole 24 ore vittorio storaro motiva la scelta, la disposizione e l’andamento del suo progetto illuministico con queste parole: «le nuove luci sui fori sono state concepite cercando di raccontare, attraverso l’illuminazione stessa, i concetti legati alla vita e alle gesta dei vari imperatori. per augusto ho pensato a un’illuminazione che nasce dal basso come un sole che sorge sul mondo allora conosciuto grazie alla conoscenza e alla civiltà di roma. per nerva ho voluto sottolineare la fase di transitorietà del periodo con una serie di luci assiali che sottolineano la stasi di questa porzione di foro. infine per traiano, il conquistatore che ha esteso l’impero alla sua massima estensione storica, le luci si concentreranno sulla colonna, come attratte con un moto circolare, con due cerchi concentrici, dall’imponente colonna centrale. ma ogni singola colonna del foro di traiano sarà illuminata, non solo il celebre monumento centrale». lighting design il sapiente lavoro di francesca storaro, renderà compiuto il progetto e metterà finalmente nella “giusta” luce una parte dell’ineguagliabile patrimonio archeologico romano, affinché il visitatore possa ammirare in maniera nuova e più coinvolgente i monumenti rispetto alla visione diurna. la carica emozionale con cui il sole al tramonto, con le sue ombre portate, riveste le rovine imperiali continuerà nelle ore notturne così da creare un incanto ininterrotto che accompagnerà l’immaginario dei visitatori sui sentieri della storia. l’elevata efficienza e luminosità, la lunga durata, il risparmio energetico e non ultimo le dimensioni compatte che consentono di integrarli nelle strutture architettoniche sono alcuni dei motivi essenziali che hanno suggerito a francesca storaro la scelta tecnica dei led. i corpi illuminanti sono infatti dotati di led dai binning accuratamente selezionati in modo da garantire un flusso luminoso e una resa cromatica diversificata per le diverse esigenze e caratteristiche del progetto. per creare la luce orientata francesca storaro ha pensato di utilizzare dei corpi illuminanti in cui si impiegano particolari sistemi di proiezione come narrow spot, spot, flood, wide flood, wallwasher a luce bianca calda o neutra, con diverse classi di potenza, che garantiscono un’alta precisione progettuale. una volta montati i proiettori saranno gestiti da un sistema di controllo dali o dmx, che permetterà di regolare l’intensità luminosa degli apparecchi a led (possono essere “dimmerati” con continuità dal 100% all’1% senza effetti negativi su caratteristiche come la tonalità di luce e la resa cromatica) rendendo possibile la programmazione di diversi scenari luminosi così che la luce arrivi a riscrivere il linguaggio dell’architettura antica. cultura e scienza del colore color culture and science 56 cultura e scienza del colore color culture and science | 04/15 la prima edizione del premio colore della associazione italiana colore ha visto rendere onore al lavoro di un grande artista che usa sapientemente sapori e colori in cucina. le motivazioni raccontano la scelta di premiare gualtiero marchesi, un cuoco, ma che cuoco! “il premio colore 2015 va a un grande maestro, al cuoco italiano più famoso nel mondo, a colui che ha saputo rendere il colore un tratto caratteristico e distintivo di ogni sua preparazione, in una sintesi perfetta tra gusto ed estetica, tra sensi e bellezza. nelle sue creazioni il colore è un messaggio chiaro, diretto, quasi ancestrale, una parte complementare ed imprescindibile nell’armonia complessiva dei sensi. la sua tavolozza è misurata per ogni piatto, a voler esaltare al massimo l’intenzione poetica senza fraintendimenti, in un prezioso lavoro di sintesi. ha saputo tradurre il suo amore per l’arte in piatti memorabili plasmando le materie prime in forme e colori che diventano a loro volta arte, prima che cibo. composizioni che rendono omaggio alla tradizione dei grandi maestri da lui amati, uscendo dalle tele, dai musei, per diventare esperienza multisensoriale. i colori di gualtiero marchesi nutrono gli occhi di bellezza, nutrono di emozioni, di cultura, di memorie … nutrono la nostra anima prima del nostro corpo, grazie maestro.” le motivazioni del riconoscimento ci raccontano quanta parte il colore abbia nella cucina, arte sinestetica che coinvolge tutti i sensi a partire dalla vista, il primo a darci informazioni sulla qualità degli alimenti, sulla loro edibilità, ma anche il primo senso a mostrarci la bellezza. marchesi cita spesso con orgoglio una frase della figlia: “il bello puro è il vero buono” e questo premio rende omaggio ad una sapienza composta da immaginazione, cultura e abilità, alla grande sensibilità artistica che marchesi ha saputo trasmettere ai suoi figli, nipoti e ai tanti alunni spesso diventati cuochi famosi a loro volta. emanuela orlando www.orlandoprogettazione.it i colori di gualtiero marchesi rubrica | column gualtiero marchesi’s colours rubrica column the first edition of the colour price of the italian colour association has honoured the work of a great artist who wisely uses flavours and colours in the kitchen. the reasons tell the choice to reward gualtiero marchesi, a chef… and what a chef!! “the 2015 colour award goes to a great teacher, to the most famous italian chef of the world, to he who knew how to render colours a distinct characteristic in every step of his preparations, a perfect combination between taste and aesthetics, between senses and beauty. in his creations, colours always have a direct, clear, and nearly ancestral message that are complementary and essential parts to the overall harmony of senses. his palette is measured in every plate, in order to enhance the poetic intention without misunderstandings, in a precious synthetic work. he managed to translate all his love of the art into memorable dishes, moulding his raw materials in shapes and colours that become first art, then food. compositions that render homage to the tradition of his beloved masters, coming out from canvases, museums, that become an multisensory experience. the colours of gualtiero marchesi nourish the eyes of beauty, emotions, culture, memories.. nourish our soul before our body, thank you master.” these motivations show us the importance of colours in the kitchen, a synesthetic art that involves every sense starting from sight, the first to give us information on the quality of the food, on their edibility, but also the first of the five senses that shows us the beauty of the plate. often marchesi proudly quotes his daughter’s phrase: “the pure beauty is the real good” and this prize is a homage to the knowledge made up of imagination, culture and ability, to the great artistic sensibility that marchesi has been able to transmit to his children, grandchildren and to his numerous pupils, some of whom have become great chefs themselves. 5704/15 | cultura e scienza del colore color culture and science nella sua storia il colore è sempre presente così come la cultura, la curiosità, l’amore per l’arte, la musica. così racconta nella sua autobiografia il suo concetto di vivanda: «è un racconto gastronomico, un intreccio una recitazione dove gli interpreti sono gli ingredienti che si vivificano, si organizzano, interagiscono in un equilibrio di sapori, di colori, di gusto. ….» con la sua opera ha svolto un fondamentale ruolo di catalizzatore e stimolo nell’innovazione e modernizzazione della ristorazione italiana; ancora dalla sua autobiografia: «la cucina contribuisce, e non secondariamente, a fare da ambasciatrice d’italianità e creatrice d’immagine. fa parte a buon diritto dello stile italiano al pari di altre forme riconosciute come il design industriale, la moda, la musica e l’arte in generale.» uomo cordiale, raffinato e colto, gentile e spiritoso, ha saputo raccontare i suoi piatti con semplicità e ironia. ha parlato della sua vita di ricerca (“la cucina mi ha insegnato l’umiltà e la curiosità”, “la cucina è scienza, sta al cuoco farla diventare arte”) ha condiviso ricordi che intrecciano persone, passioni ed emozioni. “un cuoco senza pregiudizi, un anarchico che nel piatto riconosce solo la legge dell’equilibrio, imposta dalla natura. un pensiero condiviso con toulouse-lautrec” così gli piacerebbe essere definito. figura 1 gualtiero marchesi: riso, oro e zafferano figure 1 gualtiero marchesi: rice, gold and saffron rubrica | column in his history colours have always been present just like culture, curiosity, love for art and music have. he tells us in his autobiography his concepts: «it is a gastronomic story, a play where the actors are the main ingredients that vivify, organise, interact in an equilibrium of flavours, colours, and taste…» with his work he has taken part in a role as catalyst and stimulus of innovation and modernisation of italian restoration: «cuisine is, and not on a secondary level, an ambassador of italy and creates a renowned image of italianness. it is a key part of the italian style together with other like industrial design, fashion, music and art» a cordial, elegant, cultured, humble and humorous man who was able to recount his dishes with simplicity and irony. he has talked about his life and has shared memories that intertwine people, passions and emotions. “a chef without prejudices, an anarchic who recognises the natural law of equilibrium in his dishes. a thought shared with toulouselautrec”: this is how he would like to be defined. 58 cultura e scienza del colore color culture and science | 04/15 figura 2gualtiero marchesi: il rosso e il nero figura 3 lucio fontana: il rosso e il nero rubrica | column 5904/15 | cultura e scienza del colore color culture and science rubrica | column la cerimonia si è conclusa con un’ovazione generale, tutti i partecipanti alla conferenza si sono stretti sul palco intorno a marchesi per salutarlo, per una foto con lui, per stringergli la mano: il maestro calorosamente ha salutato tutti senza trascurare baci e abbracci per tutte le signore. the ceremony closed with a standing ovation, when all the participants reunited on stage around marchesi to greet him, take a photo, or simply to shake his hand: the master warmly saluted everyone without overlooking kisses and hugs to all the ladies in the room. cultura e scienza del colore color culture and science 129 cultura e scienza del colore color culture and science | 10 | 2018 | andrea dall’asta. the light splendour of truth. paths among art, architecture and theology from early christian to baroque issn 2384-9568 renata pompas nell’arte contemporanea la luce emessa da diversi tipi di illuminanti è materia e soggetto di numerose opere, ma lo è stata sin dall’antichità nelle sue rappresentazioni pittoriche e nell’organizzazione dei volumi e dell’illuminazione degli edifici. gli artisti, nelle diverse epoche, ne hanno interpretato non solo l’aspetto visivo, ma anche il suo significato comunicativo, simbolico e spirituale. l’interessante libro di andrea dall’asta – direttore della galleria e del museo san fedele di milano e della raccolta lercaro di bologna – indaga l’aspetto teologico della rappresentazione della luce nella pittura e negli edifici religiosi, con una scrittura limpida ed erudita. il libro la luce splendore del vero. percorsi tra arte, architettura e teologia. percorsi dall’età paleocristiana al barocco (pagg. 239, € 32) si articola in sette tappe-capitoli, arricchiti da riferimenti documentali, bibliografia e illustrazioni a colori. l’appartenenza di dall’asta (di formazione architetto) alla compagnia di gesù spiega la profonda preparazione con cui analizza la relazione tra arte e teologia, offrendo un punto di vista originale e inusuale. capitolo i. dio è luce. la luce nella tradizione biblica questo capitolo costituisce la premessa teologica della concezione della luce nel cattolicesimo: nella bibbia la luce è teofania divina di cui cristo è il logos che si fa carne. le opere religiose analizzate si fondano tutte su questo assunto, pur column review andrea dall’asta the light splendour of truth. paths among art, architecture and theology from early christian to baroque ancora editrice, milan, 2018. in contemporary art the light emitted by different types of illuminants is today matter and subject of numerous works, but it has been also in its ancient art, in its pictorial representations and in the organization of the volumes and lighting of buildings. the artists, in different period, have interpreted not only its visual aspect, but also its communicative, symbolic and spiritual meaning. the interesting book by andrea dall’asta director of the gallery and 130 cultura e scienza del colore color culture and science | 10 | 2018 | pompas r. issn 2384-9568 of the san fedele museum in milan and of the lercaro collection in bologna investigates the theological aspect of the representation of light in ancient painting and in religious buildings, with a clear and erudite writing. the book the light splendour of truth. paths among art, architecture and theology from early christian to baroque (pages 239, € 32) is divided into seven stages-chapters, enriched by documentary references, bibliography and color illustrations. the membership of dall’asta (graduated architect) to the jesus company explains the profound preparation with which he analyses the relationship between art and theology, offering an original and unusual point of view. chapter i. god is light. the light in the biblical tradition this chapter constitutes the theological premise of the conception of light in catholicism: in the bible the light is the divine theophany of which christ is the logos who becomes flesh. religious works analized are all based on this assumption, although with different expressions. chapter ii. the byzantine architecture: the theophany of light this chapter explains the “contemplation of the principle”, at the base of byzantine art, which manifests itself in the gold funds of icons and in mosaics that dematerialise the volumes of churches, transforming them into “temples of light”. chapter iii. the middle ages: from shadow to light, from death to life. this chapter describes the new aesthetic sensibility of the gothic, which empties the walls by inserting stained glass windows with “clear and shining colors” (thomas aquinas). chapter iv. the renaissance: the light of a utopia this chapter demonstrates how the light in the renaissance represents a physical phenomenon. it is an intellectual, serene con diverse espressioni. capitolo ii. l’architettura bizantina: la teofania della luce questo capitolo spiega la “contemplazione del principio”, alla base dell’arte bizantina, che si manifesta nei fondi oro delle icone e nei mosaici che smaterializzano i volumi delle chiese, trasformandole in “templi di luce”. capitolo iii. il medioevo: dall’ombra alla luce, dalla morte alla vita. questo capitolo descrive la nuova sensibilità estetica del gotico, che svuota le pareti inserendovi vetrate colorate dai “colori nitidi e splendenti” (tommaso d’aquino). capitolo iv. il rinascimento: la luce di un’utopia questo capitolo dimostra come la luce nel rinascimento rappresenti un fenomeno fisico. si tratta di una luce intellettuale, serena, in cui umano e divino si incontrano nella chiarezza della ragione. capitolo v. da correggio a tiziano, dalla notte della rivelazione alla notte del dramma. questo capitolo si concentra sull’arte della controriforma in cui una lucemateria si disintegra in ambienti notturni, simbolo dei drammi umani. capitolo vi. caravaggio e “caravaggismo”. la luce della grazia questo capitolo mostra come nel xvii secolo la luce rappresentata dissolve il disegno, facendo vivere la materia. capitolo vii. il barocco: la gloria della luce infine l’ultimo capitolo dimostra come nel barocco il fedele è attratto verso la luce divina stesso, interpretando l’insegnamento di ignazio di loyola, per cui tutto è chiamato a essere ad maiorem dei gloriam. una dissertazione attraverso le opere dei maggiori artisti che per la prima volta svela i riferimenti religiosi della 131 cultura e scienza del colore color culture and science | 10 | 2018 | andrea dall’asta. the light splendour of truth. paths among art, architecture and theology from early christian to baroque issn 2384-9568 rappresentazione della luce, opera che interesserà sicuramente anche chi ha una buona conoscenza della storia dell’arte. light, in which human and divine meet in the clarity of reason. chapter v. from correggio to titian, from the night of the revelation to the night of the drama. this chapter focuses on the counterreformation art, in which a material light disintegrates in nocturnal environments, as a symbol of human dramas. chapter vi. caravaggio and “caravaggism”. the light of grace this chapter shows how in the seventeenth century the represented light dissolves the drawing, making the matter live. chapter vii. the baroque: the glory of light the last chapter shows how in the baroque painting the faithful is attracted to the divine light itself, which interprets the teaching of ignatius of loyola, for whom everything is called to be “ad maiorem dei gloriam”. an original dissertation through the works of the major artists, who for the first time unveiled the religious references of the representation of light: a work that will certainly interest even those with a good knowledge of the history of art. cultura e scienza del colore color culture and science 24 cultura e scienza del colore color culture and science | 03/15 manlio brusatin, architetto, storico dell’arte e docente, ha al suo attivo importanti pubblicazioni sul colore, come il fortunato storia dei colori (1999) tradotto in più lingue. il suo libro verde. storie di un colore è di 124 pagine (cm. 15,5 x 21,5), di cui 16 a colori (in verità impaginate veramente male), è composto da 6 capitoli, la bibliografia e l’indice dei nomi (€ 16,50). nell’introduzione leggiamo la sua dichiarazione d’intenti: “non credo utile scrivere la storia di un solo colore, come è già stato fatto con sbalorditivo successo. fare la storia del blu come la storia del rosso o la storia del nero sono imprese possibili a chi le rende leggibili. solo per non far sentire la mancanza di una storia del verde (in realtà già annunciata dal pastoureau. ndr.), ho pensato di non fare la storia del verde, ma alcune brevi storie di un verde vecchio e nuovo, vero o falso che sia”. i sei capitoli non sono suddivisi secondo un argomento specifico ma, come ci ha abituato brusatin, seguono un disinvolto procedere per associazioni, gremito da dotte citazioni. a cura di renata pompas recensioni manlio brusatin, verde. storie di un colore, biblioteca marsilio, venezia, 2013 michel pastoureau, verde. storia di un colore, adriano salani editore, milano, 2013 il colore verde ha interessato due studiosi, manlio brusatin e michel pastoureau, che hanno scritto rispettivamente: verde. storie di un colore e verde. storia di un colore, ingaggiando una strana competizione in cui si sono misurati nei molteplici aspetti del colore più diffuso in natura. recensioni 2503/15 | cultura e scienza del colore color culture and science recensioni il capitolo 1. il grande verde: parte dalla costruzione della città di nod fabbricata in terracotta rossa da caino, per descrivere la nostalgia per il perduto giardino del paradiso terrestre racchiusa in questo colore e allarga il discorso alle diverse ricette medioevali e rinascimentali per preparare il verde destinato alle tintorie, ai mosaici, alle miniature, alle vetrate, alla pittura. mette in relazione i giochi circensi giustinianei con i colori del calcio e delle nazioni, parla del colore dell’abito, dell’alchimia e dei blasoni. prende in considerazione il diagramma kircheriano e l’uso liturgico, stabilito da papa innocenzo iii. il capitolo 2. il cavaliere verde: prende in considerazione i colori delle fazioni circensi giustinianee, con il loro retroterra politico e ideologico, i colori dello sport, del calcio e dei ‘green tartan’ del golf, per approdare al romanzo cavalleresco del ‘cavaliere verde’, assorbito nell’ordine della giarrettiera e al verde del battesimo e dell’eucarestia. il capitolo 3. la casa verde: assume il sogno cittadino di una casa immersa nel verde che ha attraversato i secoli sin dalla fondazione dell’urbe e la costruzione dei giardini cittadini (italiano, francese, inglese, ispanico, arabo) come proiezione del paradiso perduto. la gartenhaus di goethe nel bosco di weimar è descritta come il luogo di partenza del viaggio che conduce il poeta attraverso l’italia, per poi riportarlo a casa. il capitolo 4. le pietre e le terre verdi: affronta gli aspetti misterici del colore a partire dalla ‘tavola di smeraldo’ di ermete trismegisto, raffigurata nel pavimento a intarsio marmoreo del duomo di siena; dal leone verde alchemico approda al bizantino ‘catino di smeraldo’, creduto il piatto o coppa dell’ultima cena ma in realtà fatto di vetro colorato, di cui riportata la composizione, così come per fa per i pigmenti della pittura usati da bellini, giorgione e tiziano per giungere all’antipatia degli impressionisti per questo colore. il capitolo 5. l’abito e la fata verde: a partire dal dal verde tossico delle carte da parati che avvelenò l’esilio di napoleone, giunge alla combinazione nero/verde dei truci romanzi neogotici, al verde in pittura prima e dopo le teorie di eugène chevreul, fino al al colore fin-de-siècle dell’assenzio, “un lampo verde senza commenti”. il capitolo 6. il secol verde: cioè il novecento, è il secolo crudele che ha esordito nella guerra del 1915 con il gas verdognolo, ha conosciuto lo spirito scoutistico con il suo riferimento letterario nel ‘libro della giungla’, una nostalgia del verde presente anche all’organizzazione giovanile dei pionieri sovietici, nella fiaba di peter pan, nella leggenda dello yeti. nelle città si diffondono i giardini, nella società la penicillina, la canzone dei pink floyd, l’ecologia, il verde dell’islam, quello della lega e quello della ‘green economy’. un procedere destrutturato, erudito, ricco di spunti, curioso, dalla scrittura labirintica. recensioni 26 cultura e scienza del colore color culture and science | 03/15 recensioni michel pastoureau, storico francese, specialista della cultura medioevale e della simbologia, da anni si dedica alla storia dei colori nella società occidentale con libri tradotti in più lingue di cui questo è il terzo volume, pubblicato dopo: blu. storia di un colore (2002) e nero. storia di un colore (2008), a cui seguiranno rosso e giallo. verde. storia di un colore ha 240 pagine (cm. 23 x 23), tutte a colori con una ricca ricerca iconografica che permette una lettura quasi parallela al testo, è composto da 5 capitoli divisi secondo una progressione cronologica dal neolitico ad oggi, le note e la bibliografia (€ 29,80). nell’introduzione pastoureau dichiara che a tutt’oggi “nessun ricercatore, nessun team è ancora riuscito a proporre un metodo specifico, capace di aiutare la comunità scientifica nello studio del colore (… e che nel suo libro presenterà l’universo dei colori considerandone) il lessico e gli aspetti linguistici, la chimica dei pigmenti, le tecniche di tintura, le forme del vestiario e i codici che le accompagnano, il ruolo del colore nella vita quotidiana, le norme promulgate dalle autorità, gli interventi moralizzatori degli uomini di chiesa, le speculazioni degli uomini di scienza, le elaborazioni degli uomini d’arte”, e a questa schema si attiene. un colore incerto. dalle origini all’anno mille: affronta i problemi di produzione e di nominazione del colore verde, riprende il dibattito sugli incerti confini cromatici di tutti i vocaboli del colore, esemplificato dal caso della letteratura greca, passando dai barbari e dai romani approda ai giochi circensi, al ruolo della chiesa (quasi assente nella bibbia il verde diventa uno dei colori liturgici con innocenzo iii) e dell’islam. un colore cortese. xi-xiv secolo: analizza l’importanza simbolica attribuita nel medioevo al giardino e alle piante, estesa alla primavera e poi traslata nei codici cortesi della gioventù dell’amore e della speranza e nel codice cavalleresco, a cui appartiene la leggenda di tristano, eroe verde. un colore pericoloso. xiv-xvi secolo: l’instabilità del verde nella pittura e nella tintura origina – accanto agli altri aspetti simbolici – anche un significato malefico, facendone il colore del diavolo, delle streghe, del veleno e della putrefazione. nell’araldica viene associato al piombo, a venere, allo smeraldo, al giovedì e alla forza; del verde si occupano anche i trattati sui colori e sull’abbigliamento. 2703/15 | cultura e scienza del colore color culture and science recensioni un colore secondario. xvi-xix secolo: partendo dall’iconoclastia protestante analizza il verde nella pittura, nell’abbigliamento, nelle creature soprannaturali delle fiabe, nelle superstizioni, nella pittura; il suo fascino che cattura l’attenzione dei poeti e degli artisti pre-romantici e la sua presenza nella prima coccarda rivoluzionaria del 1789. un colore tranquillizzante. xix-xxi secolo: colore di moda durante il neoclassicismo e presente nella pittura dell’ottocento, il verde viene disdegnato dalle teorie del colore che privilegiano la triade primaria del blu-rosso-giallo, è screditato dai docentiartisti della bauhaus, poi nel novecento si diffonde un verde, che pastoureau chiama ‘amministrativo’, negli uffici, nelle farmacie, negli ospedali, nello sport e poi nell’ecologia. oggi, conclude l’autore, “più che un colore è (diventato) un’ideologia, al secondo posto nelle preferenze dei colori della popolazione europea, dopo il blu”. un libro imperdibile per chi si interessa alla cultura del colore, con un impianto storico scrupoloso e una scrittura chiara e piacevole. cultura e scienza del colore color culture and science 50 cultura e scienza del colore color culture and science | 02/14 1 2 miguel neiva 1if-flup.universidade do porto, 2miguel neiva design studio, portugal coloradd . color identification system for colorblind people 1. introduction to the colorblindness problem colorblindness is the common denomination to a congenital alteration related to the incapability to distinguish several colors of the spectrum due to a visual deficiency (figure 1). this people have a normal vision relatively to the other characteristics which compose it, even though the deficiency hampers, or even makes it impossible for those afflicted to perform certain everyday social and professional tasks. colorblindness affects approximately 350 million people 10% of the world’s population and it’s a handicap usually of genetic origin associated to a flaw in the x chromosome. because of this, 98% of colorblind people are male. the first symptoms of colorblindness are detected at school age due to the difficulty in interpreting drawings, maps and identifying colored pencils. later in life a colorblind person is prohibited of performing certain jobs, while some professions will bring added difficulties. similarly, managing daily routine poses problems, as well as , for instance, buying and choosing wardrobe as well as using maps and signs to provide orientation. even while accessing internet some texts can become illegible due to the use of certain colors. some companies have started creating web pages which can be seen correctly and easily by all. this has been possible due to the rising awareness that colorblind people represent a high percentage of the world population. 2. objectives and methodologies once the problem had been identified its extent and impact on the subjects was evaluated. on a first phase of the study a sample of color blind people was identified and presented with a questionnaire. its purpose was to identify the main difficulties of the respondents concerning abstract in the most developed countries colorblindness affects 10% of the male population. this handicap incurs limitations as well as uncomfortable personal and social situations for those afflicted that depend on others to choose products in which color is a predominant factor, such as pieces of apparel and decoration. a sample group of colorblind people questioned in a recent study found relevant the development of a system which would allow them to identify colors. the development of a graphic color identification system was the answer to this need, its concept and structure making it universal, easy to communicate and memorize. this system can be applied to a variety of products and allow the colorblind to reduce or even eliminate their dependence on others. figure 1 colorblind vision 5102/14 | cultura e scienza del colore color culture and science their color blindness and the processes and methods used by them to lessen and overcome these obstacles. the collected information was treated and analyzed. based on these results a conceptual basis was defined, capable of constituting a universal method of graphic color identification, easy to comprehend and memorize. ioning its volume, guiding the eyes in understanding it, suggesting its atmosphere. 3. materials and methods using primary colors, represented through simple symbols, the system was constructed through a process of logical association and direct comprehension, allowing its rapid inclusion in the “visual vocabulary” of the user. this concept makes additive color a mental game, which lets the color blind relate the symbols amongst each other and with the colors they represent, without having to memorize them individually. the system proposed is based on the search of the pigment color, using as basis the primary colors – blue (cyan), red (magenta) and yellow its additive secondary colors (figure 2) and not the light color (rgb), because the color blind person does not possess the correct vision of the colors, nor a tangible knowledge of how their addition works. each primary color of the code is associated to three forms (figure 3) which represent red, yellow and blue; from these three is the code developed. two additional forms were added representing black and white (figure 3); in conjunction with the other elements they represent lighter or darker tons of the colors. the secondary colors can be formed using the basic forms as if “mixing” the primary pigments themselves (fig 4), making their perception and subsequently the composition of a color pallet figure 2 – primary color addition – pigment colors figure 3 – graphic symbols for 3 primary pigment-colors and white and black figure 4 – graphic symbols – three primary colors and their addition 52 cultura e scienza del colore color culture and science | 02/14 easy. by associating the icons representing white and black to define darker and lighter tones to the three basic forms and their additions, a wide palette is constructed as observed in figure 5. conventional color designations were attributed to the additions and other combinations of colors, especially those used in apparel. grey, was divided into two tones: light grey and dark grey (figure 6). the importance of gold and silver in clothes implies the creation of a specific icon. considering the logic of the codes’ construction, these colors are represented by the combination of the golden-yellow and the element representing shine to define gold; light grey with the same element identifies silver (figure 7). the totality of the code, represented in figure 8, covers a considerable number of colors and can be easily conveyed through information posted at the sales point, on web sites, or the product itself. figure 5 – graphic representation of color addition with dark and light figure 6 – on the left graphic symbols – tons of grey; figure 7 – on the right graphic symbols – gold and silvery figure 8 – monochromatic graphic code 5302/14 | cultura e scienza del colore color culture and science 4. results the application of the system is transversal to all the areas of the global society, regardless of their geographical localisation, culture, language, religion, as well as to all the socioeconomical aspects. school and stationery. it is at school-age that usually appear the first and sometimes traumatic situations and difficulties caused by the wrong color identification. the inclusion of the system in the school and stationery leads to inclusion (figure 9), allowing the colorblind kid a perfect integration, with no doubts and shames. health and services. the selection of patients at hospitals is made through color. at the er, it is carried out an evaluation of the grade of “gravity” of a patient and a bracelet corresponding to a certain grade of priority is provided. the inclusion of the system in hospital services and spaces where color is an element of identification and guidance makes orientation and easier task to colorblind. in many places, color is the element of identification of the different services. a colorblind, resulting from its handicap, can not identify the color and its meaning. also, many medicines have color as an identifying factor (figure 10) transports. the metro system maps are a different context but equally valid on what concerns the use of the color identification code, in this case to individualize the different transit lines (figure 11). figure 9 – school material (real implementation) figure 10 –heath and hospitals (real implementation) figure 11 – metro map oporto (real implementation) 54 cultura e scienza del colore color culture and science | 02/14 clothing and textiles. the developed code can be applied in multiple contexts in which color is important. one of the most relevant fields of application is in apparel and the color identification symbols can be applied to tags or integrated into the clothes themselves, similarly to maintenance and care information. the simple and stylized graphics and its monochromatic nature reduce the production cost of the labels in paper or cardboard, textile or stamp (fig 12) and other implementation in cross-sector (fig 13). 5. conclusions each day society grows more individually centred. each person, sometimes, becomes totally dependant on itself and asking for another person’s help, besides creating some frustration and feelings of dependence, is not even always possible. the “wrong” interpretation of colors can harbor insecurity in social integration of the individual whenever the projected personal “image” is a key factor in rendering judgment. the color identification system, aimed at color blind, can be greatly beneficial to a group which represents such a significant percentage of the population. its use, given the characteristics of the system, means a practically insignificant cost and its adoption by the industry and society can improve the satisfaction and wellbeing of a group of individuals whose particular vision characteristics deprive them of a fully independent and tranquil every day experience of choosing their clothes. bibliography a. hogg, michael, vaughan, granham, social psychology, 2ª ed, prentice hall, 1998 arnhein, rudolf, arte e percepção visual, ed. livraria pioneira editora, 1982 dubois, bernard, compreender o consumidor, publicações dom quixote, 1993 frutigier, adrian, signos, símbolos, marcas y señales, ed. gustavo gili, 1981 learch, edmundo, cultura e comunicação, edições 70, lisboa, 1993 worsley, peter, introdução à sociologia, publicações dom quixote, 1993 lanthony, philippe, science et vie, nº216, september 2001 yanoff m, duker js, augsburger jj, et al., ophthalmology, 2nd ed. st. louis, mo: mosby; 2004:34. goldman l, ausiello d. cecil textbook of medicine, 22nd ed. philadelphia, pa: wb saunders; 2004:2410. figure 12 application clothing tags (real implementation) figure 13 application clothing tags (real implementation) cultura e scienza del colore color culture and science 3501/14 | cultura e scienza del colore color culture and science l’apparato visivo nei primi mesi di vita risente in maniera determinante dell’influenza ambientale: la maturazione visiva è strettamente legata allo stimolo. gli stimoli devono essere adeguati alle capacità visive e cognitive del bambino; i colori, come le figure e le dimensioni e i patterns dovrebbero variare con la crescita. se gli stimoli sono troppo semplici il bambino li guarderà poco perché poco interessanti, viceversa stimoli troppo complessi saranno guardati poco perché troppo faticosi. nei primi mesi i neonati colgono solo differenze di chiarezza, dai tre mesi iniziano a discriminare le tinte e solo dopo i dodici mesi percepiscono differenze di saturazione. 1. introduzione un bambino appena nato, che sta sviluppando la sua capacità visiva, inizia a distinguere i contorni delle forme per differenze di luminosità, successivamente distingue il movimento; poi ancora la figura e la forma. il riconoscimento del colore costituisce l’ultima fase dello sviluppo. alla nascita il neonato è in grado di captare gli stimoli provenienti dall’ambiente circostante, ma non è in grado di elaborarli, di organizzarli in immagini e quindi di capirli. la sua capacità di vedere va di pari passo alla sua capacità di capire ciò che vede. francesca valan, studio@francescavalan.it studio francesca valan la percezione del colore nascita ai 3 anni 15 giorni 1 mese 0 giorni 0 m 1 m 3 m 6 m 9 m 12 m chiarezza saturazionetinta percepisce vede guarda esplora gattona cammina 0 giorni 15 giorni 1 mese 36 cultura e scienza del colore color culture and science | 01/14 un bambino vede correttamente tutti i colori già prima di un anno, ma solo verso i tre anni è in grado di nominarli e di identificarli. infatti l’identificazione e il nome dei colori sono funzioni della corteccia celebrale e sono il risultato dell’educazione più che risposte istintive, riflesse e reattive. 2. fasi dello sviluppo percettivo semplificando, lo sviluppo percettivo può essere scandito in tre fasi: 1° fase, da 0 a 3 anni l’attenzione del bambino è posta sulla forma. in questa fase gli elementi strutturali della forma sono più importanti del colore. solo quando le forme sono molti semplici, già conosciute e quindi non più informative, come ad esempio un cerchio, viene privilegiata la lettura del colore a quella della forma. 2° fase, da 3 a 5 anni l’attenzione del bambino è posta sul colore. in questa fase il bambino conosce già il mondo delle forme e quindi l’attenzione si sposta sul colore. nelle sue scelte il colore diventa l’elemento più importante, mentre la forma assume un ruolo secondario. forme uguali ma di diverso colore vengono percepite come diverse, viceversa forme diverse ma dello stesso colore vengono percepite come uguali. 3° fase dopo i 5 anni la forma torna ad essere predominante sul colore. dopo i cinque anni, in coincidenza con l’inizio della scuola, e con la necessità di distinguere diversi caratteri per imparare a leggere e a scrivere gli aspetti metrici della forma tornano ad avere la priorità sul colore. colori con un basso impatto visivo facilitano la lettura delle forme e l’apprendimento della lettura e della scrittura. dall’età scolare in poi le scelte cromatiche sono determinate da altri fattori, quali ad esempio le influenze culturali e le tendenze del gusto; e anche dal rapporto personale che ogni individuo ha con il colore. 0 – 15 giorni altissimi contrasti di chiarezza dal 100% al 50% tra figura e fondo il bambino è attratto da fonti luminose. il sistema visivo, nei primi giorni non si è ancora sviluppato completamente e il bambino distingue la luce dal buio e comincia a distinguere le forme guardando i contrasti di chiarezza dei contorni. la sua acuità visiva è bassissima (05/10), riesce a distinguere le sagome ma non i dettagli di una forma. l’interesse visivo del bambino è limitato ad oggetti distanti 20 centimetri, che corrisponde alla distanza dell’occhio di un bimbo, tenuto in braccio, dal viso materno. l’unico elemento del colore che è in grado di percepire è il contrasto di chiarezza. colori ad alto contrasto e luci adeguate rappresentano già nei primi giorni dei potenti fattori di maturazione visiva. 15 giorni alti contrasti di chiarezza dal 50% al 30% non ha ancora il pieno controllo dei muscoli oculari e si stanca presto. riesce a fissare per qualche momento un oggetto posto ad una distanza massima 30 cm, bene illuminato, ed è in grado di seguirne il movimento purché sia lento e non più ampio di qualche cm. di fronte ad una zona omogenea di colore e ad una zona che ha la stessa luminosità ma sulla quale è stato disegnato un pattern, il bambino guarderà sempre di più la seconda. uno degli stimoli più importanti dei primi giorni di vita sono le strutture orizzontali e verticali dello spazio. il bambino vede abbastanza bene solo figure di colori molto contrastati e relativamente vicine. 1 mese contrasti medi di chiarezza (dal 30% al 15%) tra figura e fondo non si limita a vedere ma comincia a guardare (riflesso di fissazione). riesce a vedere fino ad una distanza di 80 cm. presta attenzione a stimoli nuovi e complessi e si entusiasma per oggetti che si muovono ed emettono qualche suono. durante i primi tre mesi di vita si guarda attorno in cerca di informazioni che gli consentano di conoscere l’ambiente che lo circonda per capire chi è e dove si trova. i suoi occhi si concentrano sui contorni degli oggetti che sono i punti che hanno il maggior contenuto di informazioni perchè definiscono le forme. se i suoi occhi sono in grado di captare le differenze di tinta, il cervello non è ancora interessato a decodificarli. e’ in grado di distinguere dettagli sempre più piccoli e contrasti di chiarezza sempre più bassi; se a due settimane il contrasto minimo percepito è del 50%, a otto settimane distingue contrasti anche del 30% di chiarezza, a 12 settimane arriva a distinguere contrasti del 10%. 3701/14 | cultura e scienza del colore color culture and science 2-3 mesi colori primari e bassissimi contrasti di chiarezza dal 15% al 5% fra i due e tre mesi segue le immagini in movimento ruotando il capo ed è in grado di convergere gli occhi se gli si avvicina un oggetto. nei primi mesi della sua vita post-natale la sua capacità visiva fa dei progressi enormi; verso le 6 settimane il bambino guarda la madre negli occhi, e riesce a distinguere gli oggetti: è un aspetto molto importante dell’organizzazione del suo mondo visivo. dopo le 6 settimane la maturazione cerebrale gli consente di organizzare alcune informazioni del mondo che lo circonda: riesce a stabilire delle relazioni fra le percezioni visive e quelle uditive e ad avere una percezione del tempo, ricordando il passato e anticipando i gesti. sarà in grado di aprire la bocca alla vista del biberon e a tendersi in avanti per essere preso in braccio. verso le 6-7 settimane è già in grado di distinguere fra superficie e volume e verso le 10 settimane distingue una superficie concava da una convessa. dopo 10-12 settimane distingue il viso umano e risponde a sorrisi, smorfie e movimenti delle labbra. comincia a distinguere i colori principali, rosso, giallo, verde e blu e percepisce differenze di luminosità anche del 5% 4-6 mesi differenze di tinta fra colori primari e secondari verso i 4 mesi e mezzo riesce ad agguantare l’oggetto e quindi ad esplorarne le qualità tattili oltre che a quelle visive. i suoi occhi lavorano assieme per determinare la distanza di un oggetto interessante, permettendogli di avvicinarsi e afferrarlo per poterlo analizzare. questa capacità (riflesso di prensione) è in rapporto con l’ambiente reale; bambini poco stimolati raggiungono la cordinazione vistaprensione molto più tardi, mentre bambini inseriti in un mondo visivo con troppi stimoli afferrano gli oggetti molto prima, verso i 3 mesi, ma l’attenzione visiva è più debole e perdono la fase importante di osservazione delle mani. un giusto grado di stimolazione migliora l’attenzione visiva. tra il quarto e il quinto mese mette a fuoco immagini fino a qualche metro di distanza, e distingue chiaramente alcuni colori; il rosso, il verde e il blu. a sei mesi sposta lo sguardo da un oggetto ad un altro ed è attratto da oggetti di piccole dimensioni. in questa fase è importante che abbia a disposizione oggetti con diverse superfici tattili: lisci e ruvidi, duri e soffici e molto colorati, e anche oggetti con un fronte e un retro che lo aiutino a sviluppare la visione a rilievo. 9-12 mesi differenze di tinta fra tutti i colori puri a 10 mesi raggiunge la coordinazione degli occhi che gli consente di vedere la profondità (visone stereoscopica). ora che il bambino ha sviluppato la binocularità, una superficie bidimensionale non è più così interessante per lui. tramite l’indagine visiva dello spazio è ora in grado di capire dove sono localizzate le cose e di ottenere informazioni sulla solidità e presenza di oggetti e persone. per lui è importantissimo guardare mentre tocca, odora, gusta per mettere in relazione tutti gli imput e memorizzare i dati. in seguito gli basterà vedere un oggetto per riconoscerlo in tutti i suoi aspetti tattili, olfattivi e gustativi perché integrerà l’immagine dell’oggetto con le informazioni già memorizzate: non vorrà bere uno sciroppo amaro una seconda volta! un bambino può conoscere tutto ciò che vede e comprende: tutto ciò che conosce determina la sua intelligenza culturale. ogni stimolo diverso, ogni materiale, odore o sapore sono informazioni importantissime per il suo data-base. anche la diversità di colore è un informazione: è in grado di captare tutte le differenze di tinta di colori molto saturi. 1 anno variazioni di chiarezza e saturazione il suo sistema visivo è completo e vede come un adulto. tra uno e due anni raggiunge il pieno controllo dei muscoli oculari e può mettere a fuoco oggetti a qualunque distanza. distingue bene forme diverse: cerchio, quadrato, e preferisce oggetti molto colorati. il bambino è in grado di distinguere tutti i colori e di apprezzarne le differenze, anche se non è ancora in grado di pensare il colore separato dal supporto e quindi di nominarlo. contrasti cromatici di tinta, di chiarezza e di saturazione i colori cominciano a diventare informazioni da discriminare, il suo panorama cromatico deve comprendere tutti i colori, da quelli primari a quelli secondari, da quelli ad alta saturazione a quelli più neutri. 38 cultura e scienza del colore color culture and science | 01/14 altissimi contrasti di chiarezza dal 100% al 50% tra figura e fondo percezione stimolo 0-15 giorni alti contrasti di chiarezza dal 50% al 30% percezione stimolo 15 giorni contrasti medi di chiarezza (dal 30% al 15%) tra figura e fondo percezione stimolo 1 mese altissimi contrasti di chiarezza dal 100% al 50% tra figura e fondo percezione stimolo 0-15 giorni alti contrasti di chiarezza dal 50% al 30% percezione stimolo 15 giorni contrasti medi di chiarezza (dal 30% al 15%) tra figura e fondo percezione stimolo 1 mese colori primari e bassissimi contrasti di chiarezza dal 15% al 5% percezione stimolo 2-3 mesi differenze di tinta fra colori primari e secondari 4-6 mesi differenze di tinta fra tutti i colori puri 9-12 mesi differenze di tinta fra tutti i colori puri 9-12 mesi differenze di tinta fra colori primari e secondari 4-6 mesi colori primari e bassissimi contrasti di chiarezza dal 15% al 5% percezione stimolo 2-3 mesi 3901/14 | cultura e scienza del colore color culture and science variazioni di chiarezza e saturazione 1 anno variazioni di chiarezza e saturazione 1 anno variazioni di finitura superfici lisce / lucide / opache / trasparenti 1-3 anni variazioni di finitura superfici lisce / lucide / opache / trasparenti 1-3 anni 1-3 anni variazioni di finitura superfici lisce / lucide / opache / trasparenti tra uno e due anni il bambino raggiunge il pieno controllo dei muscoli oculari, e riesce a distinguere e a seguire il movimento di oggetti lontani e a riconoscerne distintamente i colori. verso i due anni è in grado di discriminare perfettamente tutti i colori, distingue bene differenze di tinta, di chiarezza e di saturazione ed è in grado di appaiare forme e colori. prima dei tre anni comincia a riconoscerli e a nominarli. a tre anni utilizza intenzionalmente i colori, ed è in grado di esprimere le sue preferenze cromatiche. crescendo la percezione del colore sarà sempre meno una sensazione emozionale e sempre più una attività cognitiva. dopo i tre anni gli schemi policromatici non sono più informativi per lui, ha bisogno di altre informazioni ed è pronto a distinguere altri aspetti di un oggetto: la finitura superficiale e il materiale. oggetti di un unico colore e di diverso materiale (monocromatici e polimaterici) portano in secondo piano il colore e gli consentono di apprezzare differenze di materiale:legno, plastica, metallo; e di finitura: lucido, opaco, ruvido… bibliografia occhio, cervello e visione, david h.hubel – zanichelli editore 1989 forma e colore nel mondo visivo dei bambini, giorgio tampieri – cappelli editore 1970 il test dei colori, max lusher – casa editrice astrolabio 1976 la scoperta del bambino, maria montessori – garzanti 1999 l’alba dei sensi, le percezioni sensoriali del feto e del neonato, etienne herbinet e marie c. busnel – cantagalli 2000 cultura e scienza del colore color culture and science 8 cultura e scienza del colore color culture and science | 01/14 1anna j. berolo beroloanna@gmail.com 2desirée sabatini 1cristian bonanomi cristian.bonanomi@unimi.it 1davide gadia davide.gadia@unimi.it 1daniele marini daniele.marini@unimi.it 1alessandro rizzi alessandro.rizzi@unimi.it 1dipartimento di informatica università degli studi di milano 2centro teatro di ateneo sapienza università di roma il restauro del colore digitale: un approccio basato sull’apparenza abstract in questo articolo presentiamo un approccio quasi-non supervisionato al restauro digitale del colore nei film, ispirato a meccanismi di percezione visiva. il metodo presentato utilizza uno spatial color algorithm [1] per restaurare l’apparenza del colore piuttosto che il colore fisico. il lavoro presenta anche due esempi di restauro basati su questo approccio. 1. introduzione “tra cinquecento o mille anni si studierà il primo secolo del cinema in ogni suo aspetto, se ne vedranno e rivedranno i film. quando le future generazioni si domanderanno incredule perché “loro” hanno permesso che così tanto andasse distrutto, quel “loro” siamo “noi”. salvare il primo secolo del cinema è il nostro grande compito” [martin scorsese, 1994]. dalla sua invenzione, verso la fine dell’ottocento, il cinema è diventato la più importante manifestazione di cultura popolare , divenendo di fatto, insieme ai libri, la nostra memoria storica e culturale. tuttavia, circa l’80% della produzione cinematografica tra gli anni 1910-1920 è andato perduto. da qui la necessità etica e morale di conservare e restaurare quelle immagini che rappresentano la nostra memoria sociale. tutte le tipologie di pellicole a colori, anche le più recenti, sono soggette all’invecchiamento dei coloranti organici contenuti nell’emulsione. è un processo naturale e consiste in un disequilibrio dei valori cromatici e una perdita del contrasto. gli effetti percettivi del decadimento si traducono nella comparsa di una alterazione cromatica predominante, una perdita di contrasto e una desaturazione delle tinte. numerose procedure di restauro sono state proposte, ma tutte prevedono la riproduzione dei colori solo per approssimazione, e questo per l’impossibilità di ricreare i materiali d’epoca. il restauro classico della distorsione cromatica introdotta dal degrado degli strati fotosensibili della pellicola avviene per lo più mediante l’utilizzo di strumenti fotochimici. questi interventi di restauro richiedono molta supervisione umana e un costante controllo del lavoro, il tutto ad un costo molto elevato. il restauro digitale del colore si propone come una tecnica alternativa e innovativa rispetto al restauro chimico. le tecniche digitali consentono, con costi nettamente inferiori, di rimuovere la dominante cromatica, equalizzare l’istogramma espandendo il range dinamico e ravvivare i colori desaturi di un immagine, il tutto senza una costante supervisione da parte di personale qualificato. in questo articolo presentiamo un approccio alternativo al classico restauro digitale del colore, basato sull’idea di recuperare l’apparenza del colore piuttosto che il segnale originale. nel seguito descriviamo i passi necessari per il restauro digitale e uno strumento software progettato per questo scopo. infine mostreremo alcuni risultati ottenuti tramite questa tecnica. 2. le fasi del restauro digitale si distinguono due macro fasi nel restauro digitale. la prima è composta dallo studio effettivo dell’opera da un punto di vista storico, e da un’analisi tecnica per individuare le azioni necessarie per il recupero delle informazioni cromatiche e della dinamica. la seconda fase è mirata all’utilizzo di tools digitali per il restauro vero e proprio. 2.1 suddivisione in scene una fase preliminare al restauro digitale, prevede la suddivisione dell’opera in scene, che andranno poi analizzate ed elaborate separatamente. la suddivisione delle scene presenti nell’opera è fatta inizialmente in maniera manuale, tenendo conto delle variazioni spazio-temporali; successivamente le scene sono valutate e su di esse è fatta una ulteriore suddivisione in base alle variazioni di sfondo e dei soggetti presenti nella scena. una ulteriore suddivisione è effettuata in presenza di dissolvenze fade-in e fade-out. 2.2 key frame una fase preliminare al restauro digitale, prevede la suddivisione dell’opera in scene, che andranno poi analizzate ed elaborate separatamente. 901/14 | cultura e scienza del colore color culture and science la suddivisione delle scene presenti nell’opera è fatta inizialmente in maniera manuale, tenendo conto delle variazioni spazio-temporali; successivamente le scene sono valutate e su di esse è fatta una ulteriore suddivisione in base alle variazioni di sfondo e dei soggetti presenti nella scena. una ulteriore suddivisione è effettuata in presenza di dissolvenze fade-in e fade-out. 2.3 supporto storico durante il restauro digitale di una pellicola cinematografica a colori è facile riscontrare errori dovuti alla mancanza di informazione dell’ambientazione dei soggetti filmati, sia che si tratti di live action o animazione. per questo motivo, quando si effettua un lavoro di restauro dell’apparenza del colore e della dinamica, si procede preliminarmente con una ricerca e uno studio della pellicola,delle componenti della scena, e dell’eventuale materiale di supporto: collocazione spaziotemporale, soggetti, ricerca di altro girato o di altri supporti, ecc. in uno degli esempi presentati in questo articolo (la lunga calza verde”), è subentrata la necessità di consultare l’archivio storico della fondazione luigi micheletti, proprietaria insieme all’istituto luce della pellicola originale del cortometraggio, nello specifico la presa in visione, coadiuvati dal responsabile dell’archivio daniele mor, dei rodovetri originali. purtroppo anche i rodovetri presentavano l’inesorabile degrado del tempo, ma è stato comunque fondamentale consultarli per avere indicazioni sul risultato a cui indirizzare il processo di restauro digitale. 2.4 aceforfilm purtroppo, in molti casi non è possibile avere informazioni esatte sul colore originale dei frame, a causa di un degrado troppo avanzato, e di mancanza di altro materiale di supporto che permetta di avere informazioni più precise. un suggerimento alternativo al restauro esatto del colore è stato proposto da e. gombrich [2], che evidenzia l’importanza del recupero della percezione dell’opera, non solo dell’informazione cromatica. l’approccio adottato nella nostra pipeline di restauro digitale si basa quindi sul recupero dell’apparenza cromatica della scena, piuttosto che su una stima arbitraria dei colori originali. a tal fine abbiamo utilizzato come strumento per il restauro digitale una tecnica appartenente alla famiglia degli spatial color algorithms (sca). questo tipo di algoritmi elaborano ogni pixel dell’immagine sulla base dell’informazione contenuta negli altri pixel, applicando trasformazioni che si basano quindi sul contesto della scena, in maniera simile ad alcuni meccanismi tipici della percezione visiva, quali la costanza cromatica. inoltre, questo tipo di algoritmi lavora in maniera quasi-non supervisionata, sulla base dell’impostazione di pochi parametri iniziali. in particolare è stata utilizzata una variante dell’algoritmo ace (automatic color equalization) [3,4]. la principale caratteristica di ace è la correzione cromatica data-driven: l’algoritmo è in grado di correggere dominanti cromatiche non conosciute a priori e di eseguire un’estensione del contrasto e del range dinamico dell’immagine . la variante utilizzata per il restauro digitale, chiamata aceforfilm [5], presenta inoltre una serie di funzioni che permettono di ottenere naturalezza nelle immagini restaurate e preservare la forma dell’istogramma originale in numerose situazioni di degrado avanzato . queste opzioni sono state introdotte per evitare che l’algoritmo cambi precise scelte artistiche del regista. l’opzione keep original gray (kog) “forza” l’elaborazione dei canali cromatici intorno al grigio medio: in questo modo i valori medi originali (indipendentemente sui canali r, g, b) sono preservati. il risultato è un istogramma con una forma più simile all’originale. questa funzione è utile per mantenere le sequenze di dissolvenza fade-in e fade-out. l’opzione keep original color cast (koc) evita la rimozione della dominante di colore, che potrebbe essere stata introdotta per intenti artistici, e modifica solo il range dinamico. infine, l’opzione keep original dynamic range (kodr) serve eventualmente per rispettare le intenzioni originali del regista di non usare l’intero range dinamico della pellicola e ottenere particolari effetti visivi come immagini in chiave alta o chiava bassa. 3. esempi di restauro di seguito mostriamo due esempi di restauro ottenuti grazie all’applicazione di aceforfilm. nel primo caso si tratta di un film live action, nel secondo di un film d’animazione. 3.1 il racconto della stura il primo esempio riguarda il restauro digitale dell’apparenza del colore del cortometraggio “il racconto della stura” [6], un documentario di 8 minuti e 51 secondi di ermanno olmi, filmato nel 1955, che documenta la costruzione di un impianto idroelettrico dell’enel nella val di stura di demonte (cn). il documentario è stato gentilmente fornito dall’archivio nazionale cinema d’impresa di ivrea. l’analisi dei frame originali rivela una dominante di colore magenta non uniforme (figura 1 a 10 cultura e scienza del colore color culture and science | 01/14 figura 1 a sinistra: frame originale digitalizzato numero 3287 de “ il racconto della stura”. a destra: esempio di restauro del frame usando aceforfilm. figura 2 istogrammi dei canali rgb del frame originale de “il racconto della stura”. figura 3 istogrammi dei canali rgb del frame restaurato. 1101/14 | cultura e scienza del colore color culture and science figura 4 a sinistra: frame originale digitalizzato numero 322 de “la lunga calza verde”. a destra: esempio di restauro del frame usando aceforfilm. figura 5 istogramma del frame originale de “la lunga calza verde”. figura 6 istogramma del frame restaurato. 12 cultura e scienza del colore color culture and science | 01/14 sinistra, relativi istogrammi dei canali rgb in figura 2). come si può osservare nella figura 1 a destra, il filtraggio con aceforfilm permette la rimozione della dominante, espande il range dinamico e aumenta il contrasto. in figura 3 viene mostrato l’effetto dell’algoritmo sugli istogrammi dei canali rgb dell’immagine. 3.2 la lunga calza verde il secondo esempio riguarda il cortometraggio d’animazione “la lunga calza verde” [7]. quest’opera è stata realizzata nel 1961 per la regia di roberto gavioli, sceneggiatura di cesare zavattini e disegni di paolo piffarerio, produzione gamma film e istituto luce. il cortometraggio è stato gentilmente concesso in formato digitale dalla fondazione luigi micheletti di brescia. il materiale sul quale si è lavorato era una copia riversata su dvd con una risoluzione standard pal 720 x 576 . l’analisi iniziale del materiale ha evidenziato una notevole desaturazione del colore e una presenza di dominante su numerosi frame (figura 4 a sinistra, relativi istogrammi dei canali rgb in figura 5). unico supporto per la comparazione erano i rodovetri originali ma anch’essi per la natura del supporto e dei coloranti avevano subito un notevole degrado. in figura 4 a destra viene mostrato un esempio di restauro utilizzando aceforfilm, con i relativi istogrammi in figura 6. come si può notare, anche in questo caso l’applicazione dell’algoritmo permette di recuperare il range dinamico, aumentando inoltre la saturazione dei colori. il restauro di questo cortometraggio è stato realizzato in collaborazione con gli studenti del laboratorio di “restauro digitale dell’immagine digitale” dall’università la sapienza, guidati da anna berolo e dalla coordinatrice del corso desirée sabatini. 3.3 post-elaborazione e coerenza finale dato che il degrado nelle pellicole non è costante, il decadimento dei coloranti organici segue il medesimo andamento. nei casi in cui la percentuale di alterazione è troppo elevata, è comunque necessario a volte, dopo l’applicazione della tecnica di restauro digitale, intervenire comunque manualmente su alcuni frame con tecniche di fotoritocco. quest’ultima fase è necessaria a volte anche prima del montaggio finale dei frame restaurati, per controllare la coerenza dei frame adiacenti tra le scene. pertanto è fatta una ulteriore revisione per controllare e correggere la continuità nella luminosità, nel contrasto e nel colore tra le scene adiacenti , in particolare modo tra quelle scene dove non era presente una variazione spaziotemporale, al fine di evitare effetti di flickering. 4. conclusioni abbiamo mostrato in questo articolo un approccio differente al restauro digitale del colore dei film, ispirato da principi di apparenza del colore. si è inoltre mostrata la flessibilità e l’efficacia di aceforfilm per realizzare un restauro del colore quasi-non supervisionato, sia su un film live che d’animazione. grazie all’applicazione di aceforfilm è infatti possibile operare sulla rimozione di dominanti del colore, equalizzare dell’istogramma, controllare il range dinamico e il contrasto globale e locale, e aumentare la saturazione. bibliografia [1] a. rizzi and j. mccann, “on the behavior of spatial models of color,” in proc. of electronic imaging 2007, s. jose, california (usa), 2007. [2] e.gombrich, arte e illusione. studio sulla psicologia della rappresentazione pittorica. einaudi, 1960. [3] a. rizzi, c. gatta, d. marini, “a new algorithm for unsupervised global and local color correction”, pattern recognition letters, vol 24 (11), pp. 1663-1677, luglio 2003. [4] a. rizzi, c. gatta, d. marini, “from retinex to automatic color equalization: issues in developing a new algorithm for unsupervised color equalization”, journal of electronic imaging, vol. 13, no. 1, january 2004, pp. 75-84. [5] a. rizzi, m. chambah, “perceptual color film restoration” smpte motion imaging journal (society of mot¬ion picture and television engineers), vol. 19, no 8, pp. 33-41, nov-dec, (2010). [6] r. bonisoli and a. rizzi, “restauro digitale del colore: il caso de il racconto della stura,” atti della ii conferenza nazionale del gruppo del colore (siof), milan (italia), 2006. [7] a. berolo, s. brivio, d. sabatini, and a. rizzi, “il restauro del colore de la lunga calza verde,” atti della viii conferenza nazionale del gruppo del colore, bologna (italia), 2012. cultura e scienza del colore color culture and science 16 cultura e scienza del colore color culture and science | 01/14 2. l’esperimento abbiamo usato tessuti molto sottili per produrre impressioni di trasparenza basate su stimolazioni visive naturali. per fornire misure di tipo visivo dei colori usati abbiamo seguito un procedura di colour matching, consistente nell’aggiustare, sullo schermo di computer, il colore di una zona di confronto per renderlo uguale al colore di una zona test. queste zone test erano le diverse aree di un mondrian presentate in un’altra parte del monitor e osservate attraverso veli colorati, tenuti nella posizione corretta pressate tra due vetri sottili, e illuminati in modo indipendente da un proiettore kodak carousel. la luce proveniente dal proiettore passava alcuni filtri che ne determinavano la corretta intensità e cromaticità. 2.1. materiali e metodi sono stati utilizzati dieci veli di colore diverso, illuminati da una sorgente ad incandescenza, filtrata per ottenere una temperatura di colore corrispondente a circa 5000k (figura 1). la loro forma era trapezoidale in modo che, dopo essere stato compressi tra due vetri chiari e posizionati davanti al monitor a circa 45°, la loro proiezione sull’occhio dell’osservatore era rettangolare, coprendo completamente il mondrian colorato presentato sullo schermo; solo il fondo bianco del monitor sporgeva al di fuori dell’area filtrata. questo sfondo bianco del 1. introduzione da un punto di vista percettivo la trasparenza fenomenica consiste semplicemente nella possibilità di vedere qualcosa dietro e attraverso un altro oggetto. nel mondo che ci circonda ci sono molti tipi di oggetti trasparenti [o traslucidi, a seconda della tipologia], che spesso passano inosservati se non vengono ispezionati con cura [1]. uno degli effetti più evidenti prodotti da un velo sulla percezione degli oggetti collocati dietro è la riduzione del contrasto a livello dei margini, insieme con una riduzione delle differenze fra i vari colori degli oggetti visti attraverso il velo [2]. è stato anche dimostrato che la variazione dei colori percepiti nello sfondo è ancora maggiore se i veli sono colorati, soprattutto per alcune combinazioni di velo e sfondo. questa variazione cromatica si traduce in una sensibile diminuzione della costanza di colore. l’interesse per questo tipo di ricerca è determinato dalla frequenza con cui, quando si dà uno sguardo all’ambiente che ci circonda, ci si trova di fronte a velature di varia natura (fasci di luci, filtri, nuvole di fumo e nebbia, stoffe, carta sottile, e così via). le ricerche di natura sperimentale compiute fino ad ora hanno quasi sempre usato simulazioni al computer, con rare eccezioni [2] [3]. al contrario, in questo studio abbiamo utilizzato veli reali, e abbiamo quindi ottenuto risultati di validità più ecologica. osvaldo da pos osvaldo.dapos@unipd.it chiara brunettin supreme_c@libero.it dipartimento di filosofia sociologia pedagogia psicologia applicata fisppa di padova riproduzione di colori parzialmente nascosti da veli trasparenti abstract questo lavoro si propone di mostrare che colori dietro veli colorati in tessuto fine appaiono notevolmente costanti. compito degli osservatori è stato quello di aggiustare i colori di un mondrian presentato su un monitor calibrato, per uguagliare i colori di un altro mondrian della stessa dimensione e forma, poste inferiormente, coperto da veli di colori diversi illuminati indipendentemente. in prove di controllo si dovevano uguagliare anche i colori degli stessi mondrian scoperti. i risultati mostrano una piuttosto buona prestazione degli osservatori nel riprodurre, con piccole differenze di colore, sia i mondrian scoperti che quelli velati, in questo secondo caso le differenze di colore tra i colori originali e quelli riprodotti sono di entità circa doppia. la relativamente buona costanza di colore ottenuta sembra dovuta alla forte stratificazione percettiva che si è realizzata tra mondrian e veli. questa stratificazione, oltre a ragioni figurali, è dovuta anche alla diposizione fisica dei veli rispetto al mondrian di sfondo, che facilita notevolmente una visione stereoscopica su distanze relativamente piccole. 1701/14 | cultura e scienza del colore color culture and science monitor appariva indistinguibile da un cartone bianco inserito al posto del velo, garantendo in questo modo che l’illuminazione reale del velo e l’illuminazione virtuale del mondrian sul monitor fossero identiche. la regolazione del colore veniva effettuata usando 8 pulsanti principali che servivano ad aumentare o diminuire l’aspetto di giallo, rosso, blu e verde di ciascuna area aggiustata, sia a passi unitari che a salti di dieci unità;, inoltre altri 8 pulsanti potevano essere utilizzati per modificare bianchezza (+1, +5), nerezza (+1, + 5), e la luminanza (+1, +10, -1, -10). i colori dei veli sono stati scelti in modo da coprire quanto più possibile regolarmente l’intera gamma delle tinte. la figura 2 a mostra i colori dei dieci veli in un diagramma a’b’ ciecam02-ucs misurati in situ contro un fondo nero, e la figura 2 b di fronte al monitor bianco. la figura 3 mostra i colori dei dieci veli ripiegati molte volte in modo da apparire opachi (l’opacità è raggiunta quando le misure strumentali rimangono costanti variando lo sfondo da bianco a nero). quando il partecipante osserva le figure sperimentali, la stimolazione che agisce sui figura 1 distribuzione spettrale di potenza radiante della sorgente esterna di luce filtrata emessa da un proiettore kodak carousel e utilizzata per illuminare i veli. figura 2 a: i colori dei dieci veli misurati su uno sfondo nero. b: i colori dei dieci veli misurati di fronte al monitor bianco, in un diagramma ciecam02-ucs. il cerchietto nero rappresenta il bianco di adattamento. figura 3 il colore dei dieci veli misurati dopo essere stati piegati molte volte in modo da apparire opachi. 1: grigio bluastro; 2: rosso metallico; 3 verde; 4: giallo; 5: verde chiaro; 6: rosso; 7: turchese; 8: viola; 9: giallo chiaro; 10: arancione. figura 4 i colori risultanti dalle combinazioni di velo e di mondrian, che costituiscono lo stimolo per la percezione della trasparenza, rappresentati in tre diagrammi a’ b’ ciecam02-ucs. in totale ci sono 90 colori, oltre i colori dei veli di fronte a sfondo bianco (in nero). in a il mondrian 1 è coperto da veli n. 2 (triangoli), 6 (rombi), 8 (quadrati); in b il mondrian 2 è coperto da veli n. 3 (triangoli), 4 (cerchi), 9 (rombi), e 10 (quadrati); in c il mondrian 3 è coperto da veli n. 1 (triangoli), 5 (rombi), 7 (cerchi). 18 cultura e scienza del colore color culture and science | 01/14 figura 5 i colori dei tre mondrian (m1: rombi; m2: quadrati; m3: triangoli) che vengono presentati nella parte inferiore dello schermo. da 1 a 9: le 9 regioni quasi-quadrate del mondrian. figura 6 media dei colori aggiustati relativamente ai tre mondrian in un diagramma a’ b’ ciecam02ucs. (m1: il primo mondrian;; m2: il secondo mondrian; m3:il terzo mondrian). 0 2 6 8 tutti m1 5.23 8.83 9.86 12.77 10.49 3 4 9 10 m2 5.56 15.31 13.74 11.37 12.42 13.21 1 5 7 m3 4.51 12.73 13.07 11.11 12.30 tabella 1 le differenze medie tra i colori aggiustati e colori di riferimento (mondrians allo scoperto) in tutte le condizioni (numerate da 1 a 10 in funzione del velo). m1, m2, m3: i tre mondrian. 0: le condizioni di controllo (senza veli); tutti (in corsivo): indica i risultati relativi a tutti i veli di ciacun mondrian. suoi occhi è determinata dalla combinazione di radiazioni provenienti sia dai veli trasparenti che dallo sfondo retrostante, entrambi colorati. pertanto è importante studiare quali relazioni sussistano tra i colori percepiti e questi stimoli (figura 4 a, b, c). in questo lavoro siamo interessati ai colori dello sfondo visti dietro e attraverso i veli trasparenti (mentre in altre ricerche si è più interessati ai colori del velo), e il compito affidato ai partecipanti era quindi quello di riprodurre quei colori nel mondrian aggiustato (senza velo). tre diversi mondrian (figura 5) tutti composti da 9 regioni quasi quadrate, ma di colori diversi per non favorire la memorizzazione dei loro colori dagli osservatori, sono stati presentati uno alla volta nella parte inferiore di un monitor quato tft, tarato ad una temperatura di colore corrispondente a 6500k, con luminanza del bianco a 131 cd/m2, gamma 2.2, guadagno 1, offset 0. nella parte superiore del monitor è stato collocato un altro mondrian della stessa forma, con colori grigi distribuiti casualmente nelle diverse aree, che serviva, nell’operazione di colour matching, a riprodurre i colori del mondrian colorato inferiore che si vedeva dietro il velo. hanno partecipato all’esperimento quattro persone volontarie, con visione normale dei colori. di fronte ad uno stesso mondrian sono stati collocati, di volta in volta, tre veli di colore diverso, tranne un caso in cui ne sono stati messi quattro (per un totale di dieci veli e tre mondrian). nelle prove di controllo i tre mondrian colorati sono stati presentati scoperti. in ogni caso i partecipanti, posti alla distanza di circa 60 cm dal monitor, in visione libera e con possibilità di muovere la testa senza però far uscire il mondrian dal velo, dovevano regolare i colori del mondrian da aggiustare in modo da farli apparire uguali a quelli osservati nella parte inferiore dello schermo. prima di terminare l’aggiustamento di un mondrian, gli osservatori sono stati invitati a verificare che il suo aspetto globale apparisse uguale al mondrian da riprodurre e di aggiungere ulteriori regolazioni fino a raggiungere l’uguaglianza ritenuta migliore possibile. la sequenza di mondrian e filtri è stata casualizzata a parte per ciascuna condizione sperimentale e ciascun osservatore. il dato utilizzato per la elaborazione finale consisteva nella deviazione del colore aggiustato rispetto a quello test, e questa deviazione è stata calcolata in termini di differenze di colore in ciecam02_ ucs (∆e’). 2.2.risultati in primo luogo, notiamo che i colori aggiustati per riprodurre il mondrian scoperto nelle prove di controllo sono stati riprodotti con precisione piuttosto buona, data l’inesperienza degli osservatori e soprattutto la distanza spaziale tra 1901/14 | cultura e scienza del colore color culture and science figura 7 media dei colori aggiustati per la condizione velo 8 mondrian 1, in un diagramma a’ b’ ciecam02-ucs. rombi azzurri:colori del mondrian 1 originale scoperto; cerchi magenta: colori aggiustati; triangoli viola: colori di riduzione, cioè i colori stimolo risultanti dalle combinazioni del velo 8 e del mondrian 1. quadrati grigi: i colori aggiustati nei controlli per riprodurre i colori del mondrian 1 scoperto. frecce continue: distanza del colore aggiustato dall’originale da riprodurre; frecce tratteggiate: distanza del colore aggiustato dal colore di riduzione. figura 8 media dei colori aggiustati per la condizione velo 3 mondrian 2, in un diagramma a’ b’ ciecam02-ucs. rombi azzurri:colori del mondrian 1 originale scoperto; triangoli gialli: colori aggiustati; cerchi viola: colori di riduzione, cioè i colori stimolo risultanti dalle combinazioni del velo 3 e del mondrian 2. quadrati grigi: i colori aggiustati nei controlli per riprodurre i colori del mondrian 1 scoperto. frecce continue: distanza del colore aggiustato dall’originale da riprodurre; frecce tratteggiate: distanza del colore aggiustato dal colore di riduzione. i due mondrian. le differenze medie di colore per ogni mondrian era: ∆e‘= 5.23 (figura 6 m1), ∆e’ = 5.56 (figura 6 m2), ∆e‘= 4.512, rispettivamente (figura 6 m3). in secondo luogo, le differenze di colore ottenute quando il mondrian colorato era velato (tabella 1) erano un circa il doppio di quelle di controllo (∆e* = 12.1 vs ∆e* = 5.10), (cioè quando i colori aggiustati riproducevano i mondrian scoperti). e’ abbastanza intuitivo che la presenza dei veli possa alterare la percezione dei colori visti dietro e attraverso di loro, e quindi diminuire la costanza di colore. dall’altro lato questa differenza è anche piuttosto piccola in confronto con altre ricerche [4]. in figura 7 è presentato un esempio di risultati, in cui si considera la condizione velo 2 e mondrian 1. vale la pena di notare che i colori corretti (diamanti) sono molto più vicini ai colori originali (cerchi) rispetto ai colori di riduzione (triangoli, quelli che sarebbero visti dagli osservatori in un contesto uniforme per esempio dietro uno schermo bianco forato [5]). se si considera che il colore ‘stimolo’ (la stimolazione della retina mediante radiazione da aree corrispondenti) corrisponde al colore ‘riduzione’ (colori percepiti in uno sfondo uniforme dal loro contesto), la differenza fra ciò che potrebbe essere previsto dalla stimolazione locale e gli effettivi risultati deve essere interpretata in termini di influenza che il contesto produce su tutti i colori percepiti. la figura 8 offre altri esempi di questo genere (tutte le condizioni sperimentali studiate danno risultati analoghi). colori riprodotti quando i veli erano al loro posto hanno mostrato deviazioni due volte, e per alcuni veli tre volte più grandi rispetto ai controlli (senza veli): ebbene queste differenze sono rilevanti, i risultati mostrano una piuttosto buona costanza di colore, in quanto i colori riprodotti sono molto più vicini al mondrian scoperto piuttosto che ai colori di riduzione [5][6]. alcune interazioni tra mondrian e veli mostrano importanti caratteristiche della percezione dei colori, riconducibili a caratteristiche fondamentali come per esempio complementarità e opponenza. 3. conclusioni la nostra ricerca aveva lo scopo di verificare che, quando si usano veli reali colorati per generare impressioni di trasparenza, si realizza il fenomeno della costanza di colore. infatti i colori che sono stati riprodotti per uguagliare le aree colorate dei mondrian velati sono stati relativamente vicini a quelli attesi. una possibile ragione della piuttosto buona costanza trovata può essere il grado elevato di trasparenza dei veli, che ha consentito di percepire i colori dietro il velo con poca interferenza. il modello di metelli [6] sembra adattarsi molto bene alle condizioni 20 cultura e scienza del colore color culture and science | 01/14 del nostro esperimento, anche se nel nostro caso tutti i colori del mondrian velato fossero completamente coperti, mentre nel modello originale dovrebbero sporgere parzialmente oltre il filtro. risultati di altri esperimenti [4] indicano che veli meno trasparenti possono ridurre fortemente la costanza di colore, contrariamente a quanto ottenuto in questo esperimento, e sono attualmente in corso ricerche orientate a verificare questa possibilità. bibliografia [1] s. hochstein, m. ahissar, “view from the top: hierarchies and reverse hierarchies in the visual system”, neuron, vol. 36, pp. 791–804, december 2002. [2] o. da pos, l. baratella, g. sperandio, c. zanella, g. zani. “lightness constancy with 3d objects of different shape and reflectance”. in: proceedings of the 26th session of the cie. beijing china, 4-11 july 2007, vol. d1, pp. 174177, beijing: ciae [3] a. gilchrist, a. jacobsen, “lightness constancy through a veiling luminance”, journal of experimental psychology: human perception and performance vol. 9 (6), pp. 936-944, 1983. [4] o. da pos, c. rao, “colours seen through transparent objects”. in aic interim meeting 2010 color and food: from the farm to the table, proceedings, ed. by j.l. caivano & m.a. lópez. buenos aires: grupo argentino del color. pp. 23-26. 2010. [5] d. katz, “the world of color”. kegan paul, trench, trubner & co. 1935. [6] f. metelli, “the perception of transparency”, scientific american 230, pp. 90-98. 1974. cultura e scienza del colore color culture and science 4503/15 | cultura e scienza del colore color culture and science 1laura bellia bellia@unina.it 1nicola agresta 1luigi rossi 1gennaro spada 1 detec, università degli studi di napoli “federico ii” measured color changes under fluorescent and led lamps 1. introduction in the field of electric lighting, the increasing popularity and spread of the led sources, together with the availability of traditional lamps with different spectral characteristics, compels the designer to consider in his choices not only aspects related to energy saving, but also to take into account lighting quality, meaning for it a correct and pleasant perception of the surrounding environment [1],[2],[3]. once fixed the values of illuminance and luminance distributions, the parameters that characterize the sources regarding quality of light, according to european standard en 12464-1[4], and that strongly influence the perception of objects and colors are the color appearance, identified by correlated color temperature (cct), and color rendering index (cri). however in presence of sources with similar cct and cri but with different spectral power distributions (spd), different perceptual effects occur [5],[6],[7]. in this paper, the effects of two kind of sources, fluorescents and leds, both with high cri, are examined by means of color measures on different objects. 2. experimental set-up 2.1. description of the test room and light sources the test room is quite 3.00m x 3.00m x 3.00m with completely blank walls (ρ m = 70%) and a false ceiling with controlled lights. the furniture consists in a desk with a chair centrally located in respect to the lights. luminaires consist in 2 fluorescent and 4 led sources. technical characteristics of each led and fluorescent source provided by manufacturer are shown in the table 1. fluorescent led lamp 4xt16/24w 1x1824/27w luminous flux 7000 lm 1824 lm efficacy 49 lm/w 64 lm/w cri 1b (80<ra<90) 90-91 for the characterization of the sources, a konica-minolta cs2000 spectroradiometer was used; the instrument was pointed towards the lamps to obtain the spds. 2.2. description of light scenes lights are connected to luxmate emotion information system by zumtobel. thanks to this device, it was possible to dim both lighting emissions and change color temperature, in order to obtain 8 light scenes with similar illuminance values on the desk, measured with 2 konica-minolta t10 lux meters centrally figure 1 – test room figure 2 – view of the false ceiling table 2 – light scenes set-up table 1 – technical characteristics of luminaires cct [k] dim [%] e m [lux] fluo 2700k 2924 100 653 fluo 3000k 3011 93 549 fluo 4000k 4178 94 558 fluo 6500k 7100 100 621 led 2900k 2940 97 634 led 3150k 3020 94 545 led 4200k 4199 95 548 led 6100k 7195 100 628 46 cultura e scienza del colore color culture and science | 03/15 located in respect to the lights. the following analyses have shown that light scenes with intermediate cct (fluo 3000k, fluo 4000k, led 3150k and led 4200k) reported results less interesting than the other scenes: so only the results of fluo 2700k and 6500k, led 2900k and 6100k will be shown. as in table 2, fluo 2700k and led 2900k scenes have nearly the same measured cct, as also fluo 6500k and led 6100k: since now, “warm lights” will be referred to first ones while “cold lights” will be referred to second ones. 2.3. description of colored objects on the desk 6 different colored objects (lego® blocks) were placed: blue, light blue, green, yellow, orange, red. for each one of them, spectral reflectance and color coordinates under illuminant d65 were measured. 3. analysis and results 3.1. spectral distribution of reflected light analysis spectral reflectance of each colored object was measured with the spectrophotometer; lamps’ spds were obtained with the spectroradiometer while spectral distribution of reflected light was obtained pointing the spectroradiometer on each colored object under each light scene. results are reported in figures 5 – 10 in which not all but just the most interesting cases were represented. for each figure, diagrams corresponding to (c) show clearly that they are the result of the combination of the previous two: where the block’s spectral reflectance increases or decreases the value of emitted light for those wavelengths in the reflection diagram is table 3 – color coordinates of lego® blocks figure 3 – spd fluorescent 2700k (a), 3000k (b), 4000k (c) and 6500k (d). figure 4 – spd led 2900k (a), 3150k (b), 4200k (c) and 6100k (d). figure 5 – blue block spectral reflectance (a), led 2900k spd (b) and spectral distribution of reflected light (c). according to the spectral reflectance, in all light scenes red component is reduced while blue one is maximized, even with warm lights as shown in the example. figure 6 – light blue block spectral reflectance (a), fluo 6500k spd (b) and spectral distribution of reflected light (c). spectral reflectance shows high values of both blue and red component, increasing block’s reflection values in low and high wavelengths. figure 7 – green block spectral reflectance (a), led 2900k spd (b) and spectral distribution of reflected light (c). green component of all lights’ spds is maximized while blue and red ones are reduced, especially with leds. specular component included excluded l* a* b* l* a* b* blue 45.68 -7.48 -41.96 42.35 -8.55 -44.87 light blue 63.76 -11.01 -27.64 61.34 -11.79 -28.95 green 60.43 -51.72 36.90 57.98 -56.32 40.75 yellow 80.84 8.48 78.32 79.15 8.65 85.39 orange 66.60 45.37 55.38 63.63 47.94 65.07 red 42.93 50.12 32.00 30.09 55.06 40.00 4703/15 | cultura e scienza del colore color culture and science figure 8 – yellow block spectral reflectance (a), led 6100k spd (b) and spectral distribution of reflected light (c). in these cases, the only notable change between lamps’ spds and reflection diagrams is the reduction of the blue component. figure 9 – orange block spectral reflectance (a), led 6100k spd (b) and spectral distribution of reflected light (c). as for the yellow block, in the reflection diagrams it’s just the blue component of lamps’ spds to be reduced. figure 10 – red block spectral reflectance (a), fluo 2700k spd (b) and spectral distribution of reflected light (c). the red block case is similar to the yellow and orange ones. amplified or reduced. as general rule, we can say that: blue prefers cold lights; light blue is better under cold lights but it doesn’t change too much with the other light scenes; green prefers cold lights; yellow is better under warm lights; orange and red are good under every kind of light. 3.2. cct and technologies comparisons after that, for each color two different comparisons were made: correlated color temperature with the same technology and technology comparison with the same cct. this analysis helped to find the best and the worst kind of light for each color. figure 11 – fluo 6500k lamp has a wide range of blue wavelenghts while fluo 2700k lamp have peaks in other colours; leds have quite the same trend but with higher values for blue and lower for red compared to the fluorescent sources. cold lights are preferred, with led 6100k as best source and fluo 2700k as worst. cct comparison for blue technologies comparison for blue fluo 2700k fluo 6500k led 2900k led 6100k figure12 – as for blue, in light blue reflection diagrams fluorescent sources have other colour components while leds don’t have the previous trend, with led 2900k having a peak in red. technologies comparison shows how all the lights cover a wide range of wavelenghts with a preference for led 6100k. cct comparison for light blue technologies comparison for light blue fluo 2700k fluo 6500k led 2900k led 6100k 48 cultura e scienza del colore color culture and science | 03/15 figure 13 – cct comparison shows how lights with the same technology have quite the same trend for green. however it’s possible to observe how cold lights have more green component than warm lights that increase red component. in this case fluo 6500k has a peak in green wavelenghts more than led as in previous cases figure 14 – considerations made about green reflection diagrams could be applied to yellow’s too: cct comparison shows how lights with the same technology have quite the same trend, with a preference for warm lights. in particular, technologies comparison shows how similar is the trend of the two sources. figure 15 – cct comparison shows how lights with the same technology have quite the same trend for orange reflection but it’s possible to see how cold lights have a wider range of wavelenghts than warm lights, in which orange and red component is maximized. figure 16 – considerations made about orange reflection diagrams could be applied to red’s: in this case too, warm lights should be preferred to cold ones. cct comparison for green technologies comparison for green fluo 2700k fluo 6500k led 2900k led 6100k cct comparison for yellow technologies comparison for yellow fluo 2700k fluo 6500k led 2900k led 6100k cct comparison for orange technologies comparison for orange fluo 2700k fluo 6500k led 2900k led 6100k cct comparison for red technologies comparison for red fluo 2700k fluo 6500k led 2900k led 6100k 4903/15 | cultura e scienza del colore color culture and science cct comparison for orange technologies comparison for orange fluo 2700k fluo 6500k led 2900k led 6100k cct comparison for red technologies comparison for red fluo 2700k fluo 6500k led 2900k led 6100k 3.3. changes of chromaticity coordinates under different light scenes cie xyz values of each colored object and xnynzn of reference white were measured under each light scene and normalized by the reference white to calculate l*a*b* coordinates using cielab equations [8]. l* a* b* c* ab h ab 1.fluo 2700k 40.74 -8.44 -32.79 33.86 1.32 2.fluo 6500k 47.09 6.85 -73.70 74.02 -1.48 3.led 2900k 34.53 -14.15 -65.54 67.05 1.35 4.led 6100k 45.17 14.12 -60.83 62.45 -1.34 l* a* b* c* ab h ab 1.fluo 2700k 60.43 -10.58 -16.84 19.88 1.01 2.fluo 6500k 63.75 -7.45 -60.21 60.67 1.45 3.led 2900k 58.57 -17.14 -38.36 42.01 1.15 4.led 6100k 64.14 -3.68 -34.89 35.08 1.47 l* a* b* c* ab h ab 1.fluo 2700k 51.82 -46.39 40.21 61.39 -0.71 2.fluo 6500k 31.51 -61.32 24.41 66.00 -0.38 3.led 2900k 46.18 -61.33 37.27 71.77 -0.55 4.led 6100k 48.58 -64.74 49.76 81.65 -0.65 l* a* b* c* ab h ab 1.fluo 2700k 94.95 10.21 93.53 94.09 1.46 2.fluo 6500k 83.97 -15.51 66.80 68.58 -1.34 3.led 2900k 95.63 11.18 99.63 100.26 1.46 4.led 6100k 90.14 -2.03 103.04 103.06 -1.55 l* a* b* c* ab h ab 1.fluo 2700k 90.49 50.73 76.57 91.85 0.98 2.fluo 6500k 77.96 36.99 37.00 52.32 0.78 3.led 2900k 91.74 49.75 87.60 100.74 1.05 4.led 6100k 84.26 43.56 80.22 91.29 1.07 l* a* b* c* ab h ab 1.fluo 2700k 68.17 53.04 49.07 72.26 0.75 2.fluo 6500k 56.54 40.84 15.46 43.66 0.36 3.led 2900k 70.03 62.95 67.73 92.47 0.82 4.led 6100k 58.95 58.80 51.42 77.11 0.72 figure 17 – l*a*b*coordinates, chroma and hue values of blue. as a general rule, fluorescent lamps give less redness-greenness to the perception of the colored object. brightness is higher with cold lights. it seems that fluo 6500k is the best one because it maximizes all values, in contrast with previous results (led 6100k). figure 18 – l*a*b*coordinates, chroma and hue values of light blue. brightness and hue are slightly higher with cold lights. chroma is much more higher with fluo 6500k. figure 19 – l*a*b*coordinates, chroma and hue values of green. in this case, every light scene maximizes a different value, so it’s not possible to define the best light, as it was noticed in the previous analysis. figure 20 – l*a*b*coordinates, chroma and hue values of yellow. led 6100k seems to be the best light since all the values are at their maximum, except for brightness that is maximized with warm lights. the only scene completely different from the others is number 2. figure 21 – l*a*b*coordinates, chroma and hue values of orange. as the graphic shows, there is not a big difference between scenes number 1, 3 and 4 (even if led 2900k maximizes brightness and chroma), with the second scene different from the others once again. figure 22 – l*a*b*coordinates, chroma and hue values of red. looking at the values and the graphic, red is nearer to orange that to the red-a* axe: in this case too, led 2900k maximizes brightness, a* value and chroma. fluo 2700k and led 6100k have good values too while fluo 6500k is the worst light again. 50 cultura e scienza del colore color culture and science | 03/15 the next diagrams are cct and technology comparisons among the 4 scenes, showing all color coordinates for each light. in the cct comparison, warm lights tend to move to the yellow-red area, even if it’s less evident for leds. in the second diagram, it’s possible to note that led 2900k reduces the distance among yellow, orange and red coordinates. in the technology comparison, the diagrams have the same shape, with a bigger chromatic variety for leds. for cold lights, led diagram is also moved towards yellow-red area. 4. c0nclusions from the obtained results it can be inferred that: • different lamps technologies with the same cct produce different effects on colored objects; • under the same technology, but with different ccts, different effects are obtained as well. color differences regard chroma, hue and value and, under the same conditions, depend on the spectral reflectance of the considered object. this study shows that the only use of parameters like cri and cct is not enough to evaluate effects on colored objects. moreover, further research is necessary to compare these results to experimental evaluations. acknowledgement the authors thank zumtobel for providing luminaires and luxmate control system. bibliography [1] boyce, p. r. (2003). human factors in lighting (2nd ed.). london: taylor & francis. [2] cuttle, c. (2004). brightness, lightness, and providing a preconceived appearance to the interior. lighting res. and technol., 36(3), 201-216. [3] quality of the visual environment committee. (2009). light + design: a guide to designing quality lighting for people and buildings (dg-18). new york: illuminating engineering society of north america. [4] cen (2011) en 12464-1light and lighting light in work places part 1: indoor work places. brussels. [5] boyce pr, cuttle c.(1990) effect of correlated colour temperature on the perception of interiors and colour discrimination. lighting res. technol 22, 19-36. [6] fotios s.a. (2006) chromatic adaptation and the relationship between lamp spectrum and brightness. lighting res. technol. 38(1), 3-17. [7] navvab ma. (2001).comparison of visual performance under high and low color temperature fluorescent lamps. journal of the illuminating engineering society, 30: 170– 175. [8] fairchild m.d. (2005) color appearance model, (2nd ed.). john wiley & sons ltd. figure 23 – cct comparisons between fluo 2700k and fluo 6500k (a), led 2900k and led 6100k (b). figure 24 – technology comparisons between fluo 2700k and led 2900k (a), fluo 6500k and led 6100k (b). cultura e scienza del colore color culture and science 43 cultura e scienza del colore color culture and science | 10 | 2018 issn 2384-9568 maria kirk mikkelsen mkm@dskd.dk designskolen kolding a colour palette methodology abstract this paper presents “the colour combination cards”; a method collection for design students to be used in the creation of colour palettes. since a design process is influenced and controlled by various methods, this project suggests using a defined methodology in the work with colour palettes in order to give more variety to the design of colour schemes. the methodology is presented to the students as method cards that can be combined and applied in their design work. the methods are divided into four categories: plan, create, adjust and review. none of the methods are conclusive but indicate possible approaches to colour work and vary from quite practical and intuitive to completely systematic methods based on theories of colour harmonies. the paper describes the methodology and concludes by presenting two cases where “the colour combination cards” have been applied in colour classes as well as a discussion on future work. keywords colour, design, method cards, design students, didactics, colour harmonies citation: kirk mikkelsen m. (2018) ‘a colour palette methodology’, cultura e scienza del colore color culture and science journal, 10, pp. 43-48, doi: 10.23738/ccsj.i102018.05 received 05 july 2018; revised 30 august 2018; accepted 03 september 2018 maria kirk mikkelsen is senior lecturer at kolding school of design in denmark. she teaches both applied design methodology as well as colour-material strategies in design. her research interests lie in the intersection between design and didactics. parallel to her academic work mikkelsen also has a carrier as a design professional creating colour-material strategies for interior spaces. 44 cultura e scienza del colore color culture and science | 10 | 2018 | 43 48 kirk mikkelsen m. issn 2384-9568 doi: 10.23738/ccsj.i102018.05 1. introduction when we look at a man-made colour scheme, we can talk about our perception of the colours and how they affect us. we can also take on a more theoretical approach and discuss contrast ratio and harmonies in the scheme. we can simply enjoy the beauty of the palette or reflect on how it brings out the best in a form. all this is about experiencing the colour scheme after it has been created. for a design student, it is also important to look at the colour scheme from another perspective. the student must curiously ask: how is this palette created? this question is directed backwards in time and focuses on the actions leading up to the finished colour scheme. a design student must as such be trained in both understanding a colour composition after it is created as well as mastering the creation itself. he must be able to formulate an intention with a colour scheme in his own work and select and apply methods to produce it. this simple question; how is this palette created? is the promotor for the development of the colour palette methodology described in this paper. the work began in 2015 at designskolen kolding in denmark. the background was observations of students’ work with colour that showed that their approach to creating palettes were often highly intuitive. the majority of students would tend to forget colour theory later in their studies and therefore not make qualified colour choices in their design projects (mikkelsen 2016). a beta-version of the colour combination cards has since been tested as a teaching tool and evaluations has led to the form the collection has today. the paper starts by introducing elements from a classical design process, that has been implemented in the colour combination cards. next follows a description of the phases and methods suggested in the methodology. the paper concludes by presenting two cases where the colour combination cards has been used in design education. 2. understanding the design process in 1926 psychologist graham wallas described the creative process in four phases; preparation, incubation, illumination and verification (jacobsen and rebsdorf 2003). since then many models to understand creative processes including design processes has been generated. in 2007, the british design council did a major study of the design process in eleven international companies. based on their observations, they developed the model the double diamond, which is a very simplified model illustrating the progress of a design process (british design counsil 2007). the model divides the process into four phases. a divergent phase is followed by a converging phase, which is repeated in the second diamond. each phase consists of a number of iterations, where ideas can be developed and tested. a divergent phase is characterized by an open-minded approach, a phase where ideas are freely created. a convergent phase is characterized by the opposite; an analytic approach for the purpose of selecting the best idea. when comedian john cleese talks about his creative work he distinguishes between an open mode and a closed mode, and states that both are necessary in creative processes (cleese 1991). professor of strategic management, roger martin has also identified these two different states of mind in design thinking, which he claims to consist of both analytic thinking and intuitive thinking (martin 2009). the structure of the colour combination cards is inspired by elements of the design profession in terms of phases, iterations and analytic versus intuitive thinking. 3. the colour combination cards the colour combination cards (mikkelsen 2018) is a colour palette methodology developed for design students. the methodology is divided into four elements: plan create review adjust. these elements can be understood as both categories of methods and phases in a colour design process. each phase indicates a certain working procedure in the design process and suggest a number of methods to be used in the specific phase. plan: the colour work in the design process begins with the student contemplating the intention behind the desired colour scheme. he will make an effort to understand his target group by studying age, gender, culture, job, and style. through this work the student will identify the target group’s wants and needs. it is also necessary for the students to have knowledge of the design field, where the colour scheme is to be implemented. is it for interior; the student can study light conditions. is it for a graphic identity; the student must consider readability and symbolic value of the colours. is it for a fashion collection; the student can look at trends etcetera. besides research in the target figure 1 a visualisation of the phases in the colour design process 45 cultura e scienza del colore color culture and science | 10 | 2018 | 43 48 a colour palette methodology issn 2384-9568 group and design field, the student must also at this stage define what he wants to achieve with the palette expression. should the colour scheme have a calming or dramatic effect? is it sophisticated or raw? artificial or natural? when the student has outlined a plan for the colour scheme he can move on to the next stage. there are five plan-cards in the method collection. four of them proposes a strategy for a colour scheme and outline as such both an expression and possible tactics to meet this expression. these four plan-cards are intended as examples that can be used by the inexperienced design student to train the thinking. the fifth plan card describes what the student should consider to be able to formulate his own plan. this card is mostly directed at the student who are already familiar with working with colours and with design processes. create: at this stage, the student will work with the first draft of a colour scheme. colours are composed to meet the plan that was defined in the previous phase. in the create-phase no judgement can take place. emphasis is placed on an open approach to ensure a creative workflow. there is room for intuition and contemplation. there are twelve create-cards in the method collection. these twelve cards each represent a method to create a colour palette. the methods range from very intuitive to very systematic approaches and are collected partly from existing colour theory and partly from interviews with practicing designers (mikkelsen 2016). review: after the open and creative process follows an analytical look at the colour scheme. here the student will stop up and hold his first draft up against the original plan and evaluate whether it meets the intentions. the student may include other people in this process, it can be a fellow student or if possible a representative from the target group. if the colour scheme is consistent with the intentions the design work is completed. if not, the design process must subsequently include one or several iterations where the colour scheme can be improved. there is only one review-card in the method collection. this card indicates a number of questions, that the student can ask himself to assess whether the colour scheme live up to the intentions formulated in the plan-phase or not. adjust: if the generated colour scheme does not meet the intentions, it can be further processed in the adjust-phase. this phase can be interpreted as an iteration of the createphase. as described in the previous chapter, working with iterations is an essential part of a design process. there are twelve adjust-cards in the method collection. these twelve cards each represent a method to vary and to improve a colour scheme. the methods range from very intuitive to very systematic approaches, and are collected partly from existing colour theory and partly from interviews with practicing designers. figure 2 shows two different illustrations of the colour design processes. the first illustration shows a process that consists of a plan-phase, a create-phase and a review-phase. the colour scheme that is generated in the create-phase is thus assessed in the review-phase to have fulfilled the intentions of the plan-phase. the design process is therefor completed. the second illustration shows a process that consists of a plan-phase, a create-phase and a series of iterations of reviewand adjust-phases. the colour scheme that is generated in the createphase is thus assessed in the review-phase not to have fulfilled the intentions of the plan-phase and must be further processed in an adjustphase. this process adjust review adjust review is repeated until the expression of the colour scheme is satisfactory. 4. the method cards the colour combination cards consists of a total of thirty methods. each method is formulated on a card. this enables the student to physically take out a card of the collection and put it on his desk in order to focus on this one method while working with it. all text and graphical design is made in black-and-white so no colour combinations are indirectly proposed. on the front the cards present a graphic that illustrates the methods, a short title, the method category and a number. on the reverse side of the card is a description of the method, possible variations figure 2 -illustrations of two variations of the colour design process 46 cultura e scienza del colore color culture and science | 10 | 2018 | 43 48 kirk mikkelsen m. issn 2384-9568 doi: 10.23738/ccsj.i102018.05 and pros and cons. overview of the thirty methods in four categories: plan-cards: no.1 balance, no.2 trend, no.3 subdued, no.4 the full circle, no.5 another plan create-cards: no.6 analogue, no.7 monochrome, no.8 complementary, no.9 split complementary, no.10 triad, no.11 tetrad, no.12 personal colours, no.13 colour separation, no.14 historical palette, no.15 commercial context, no.16 concept, no.17 random adjust-cards: no.18 value, no.19 saturation, no.20 invert hue, no.21 invert all, no.22 overtone, no.23 bridge, no.24 perfume, no.25 scale, no.26 pairing, no.27 double up, no.28 reduction, no.29 material review-card: no.30 question 5. the colour combination cards in teaching a beta version of the colour combination cards has been used in two different teaching situations at designskolen kolding. the material was first introduced in a basic colour class for bachelor students on first semester. the class is a cross disciplinary course with students from the departments of fashion, textile, accessories, industrial design and communication design. the focus of the course is on the subtractive colour theory as described at the bauhaus school in the 1920s (itten 1973). a selection of the colour combination cards was presented in a lecture and the students chose one or more of the methods to test. there was no implementation of the colour work into a design project in this course. three of the students teamed up to investigate a series of methods from the collection. because they did not have to implement the colour schemes into an actual design project they decided to investigate the methods and applied a thorough and systematic approach to the work. as a framework for their study they chose to work mainly with compositions of three colours. all these colour combinations were created freely by using the create-card no.12 personal colours. afterwards they compared their personal colours and identified differences in preference and taste. they set out to analyse the colour combinations by referring them to a selection of methods that originates from colour theory: no.6 analogue, no.7 monochrome, no.8 complementary, no.9 split complementary, no.10 triad, no.11 tetrad. this way the students used the colour combination cards not only as an inspiration to create colour schemes but also as a means to understand and analyse colour combinations. the colour combination cards has also been used in a course for fashion and textile students on the third semester. here it entered as part of a long-term design project in which students would end up with a finished garment collection or textile collection. the colour work was placed in the beginning of the project and was therefore done prior to sketching on form and pattern. in this case, the students formulated their plan as mood boards or trend forecasts, which became the fundamental starting point for the development of the entire collection. because of the use of visual mood boards most students chose to work with variations of the create-card no.13 colour separation. this method suggests figure 3 -illustration of the createcard no.8 complementary. 47 cultura e scienza del colore color culture and science | 10 | 2018 | 43 48 a colour palette methodology issn 2384-9568 separating colours from an image and use them as a colour scheme. after reviewing the outcomes all students made several adjustments using a wide range of various adjust-methods. figure 5 shows the work of a student who created her first colour scheme using createcard no.13 colour separation and evaluated her colour scheme to be too highly saturated for the fragile colour expression, she was trying to create. she therefore used the adjust-method no.23 bridge. this method suggests selecting two colours from the palette and mixing them in a scale of colours between the two. new colours can be picked from this scale and added figure 4 -student’s work with the colour combination cards in the basic colour class.. to the colour scheme. in this case, the student identified two complementary colour contrasts in a photo on her mood board and made a bridge between the two. she found muted colours in this range, that became essential to her final colour scheme. 6. conclusion and discussion the colour combination cards has been introduced in connection with two courses at designskolen kolding. based on the response received from the participating students and the evaluation from fellow colleagues at the student’s examinations, the colour methodology will be applied in figure 5 -student’s work with the colour combination cards in a design project on third semester. 48 cultura e scienza del colore color culture and science | 10 | 2018 | 43 48 kirk mikkelsen m. issn 2384-9568 doi: 10.23738/ccsj.i102018.05 following colour classes. the students with little or no previous experience with colour have used the method cards as concrete tool for making colour schemes as well as a navigator in the vast field of colour theory. the more experienced students have used the method cards as a means to challenge their preferred working procedure. apart from learning the actual procedure about creating a colour scheme the students also seem to have improved their vocabulary around colour as well as their awareness of the importance of colour. the distinction between the analytic and intuitive phases has been easily accepted, probably because the students are familiar with design thinking from other subjects in their studies. using the colour combination cards as a tool in design teaching has overall shown to be beneficial. the future work will now involve an intensified focus on the didactic challenges as new questions are rising; how might we optimize the teaching by distinguishing between basic colour knowledge and implementation of colour work in a design project? and how can we make the best use of the colour combination cards in these two cases? if the material is to be taught by others, does it need any instructions and available presentations? funding this research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. conflict of interest this research holds no conflicts of interest. bibliography mikkelsen, m.k. (2016) ‘colour combos. methods in design education’, pp.2, presented at ccs conference, krakow jacobsen, h.s. and rebsdorf, s.o. (2003) ‘ideudvikling ved kreativ innovation’, copenhagen: gyldendal, pp.134-196 british design counsil (2007) ‘eleven lessons: managing design in eleven global companies’ http://www. designcouncil.org.uk/sites/default/files/asset/document/ elevenlessons_deskresearchreport_0.pdf cleese, j. (1991) ‘creativity in management’ london: video arts martin, r. (2009) ‘the design of business: why design thinking is the next competitive advantage’ harward business school press, pp. 57-79, mikkelsen, m.k. (2018) ‘the colour combination cards’ århus: gemakker publishing mikkelsen, m.k. (2016) ‘colour combos. methods in design education’, pp.3, presented at ccs conference, krakow itten, j. (1973) ‘the art of color: the subjective experience and objective rationale of color’ new york: van nostrand reinhold cultura e scienza del colore color culture and science 26 cultura e scienza del colore color culture and science | 01/14 focalizzate all’acquisizione di informazioni preliminari sulla composizione delle pitture acriliche impiegate dall’artista. le misure di colore sono state invece finalizzate alla valutazione delle variazioni di colore eventualmente occorse durante il processo di pulitura e al monitoraggio della stabilità dell’intervento conservativo nel tempo. 2. strumentazione il sistema impiegato per l’acquisizione degli spettri di riflettanza (nell’intervallo spettrale 3202500 nm) è costituito da due spettroanalizzatori zeiss modelli mcs601 e mcs611 nir 2.2 wr. i due strumenti sono montati in un unico chassis insieme alla sorgente luminosa, una lampada alogena al tungsteno (mod. clh 600, 20w) con temperatura di colore di circa 3000 k e intervallo di emissione tra 320 e 2500 nm. i due moduli strumentali, utilizzati in cascata, consentono di ottenere, in un’unica scansione, spettri di riflettanza nell’intervallo di lunghezze d’onda dall’ultravioletto al vicino infrarosso (190 – 2200 nm) con il seguente passo di campionamento: • 0.8 nm/pixel nell’intervallo 190-1015 nm (modello mcs601 con rivelatore lineare di 1024 fotodiodi al silicio); • 0.6 nm/pixel nell’intervallo 910-2200 nm (modello mcs611 nir 2.2 wr con rivelatore lineare di 256 fotodiodi di arseniuro di indio e gallio, ingaas). il sistema è equipaggiato con fibre ottiche per l’invio e la raccolta della radiazione elettromagnetica. in particolare, la configurazione utilizzata prevede l’impiego di una sonda con geometria di illuminazione/ ripresa 8°/8°, realizzata su disegno dell’ifaccnr. in questo modo un fascio di fibre ottiche lineari invia, a un angolo di 8°, la radiazione elettromagnetica emessa dalla sorgente sull’area da analizzare (circa 2 mm di diametro), quindi raccoglie, a un angolo di 8°, la radiazione retrodiffusa dal campione e la invia ai sensori dei due spettroanalizzatori. la taratura del sistema è stata realizzata mediante uno standard di riflettanza certificato (spectralon® 99%) prima di iniziare ad acquisire gli spettri ed è poi stata ripetuta a intervalli regolari durante la campagna di misure. 1. introduzione nell’ambito dell’arte contemporanea l’espressione del messaggio creativo dell’artista è spesso considerata più importante della conservazione dell’opera d’arte stessa. considerando i dipinti murali conservati all’aperto, risulta evidente che questi tendono a perdere col tempo le loro originali caratteristiche estetiche, in particolare il colore. è pertanto molto importante, per fini documentaristici e conservativi, misurare i valori colorimetrici di tali manufatti. le misure di colore, infatti, rendono possibile seguire le procedure conservative cui l’opera è sottoposta, controllare la resa cromatica dei ritocchi o di altri processi di restauro e monitorare il comportamento dell’opera stessa durante esposizioni temporanee e permanenti. per tale ragione, ogni studio e/o intervento conservativo dovrebbe prevedere una campagna preliminare di indagini diagnostiche. il murale tuttomondo (1989), dipinto dall’artista statunitense keith haring su una parete esterna della chiesa di sant’antonio abate a pisa, è uno dei pochi murales di grandi dimensioni dell’artista ancora esistenti al mondo. esso copre una superficie di circa 180 m2 ed è costituito da 30 figure che rappresentano il tema “dell’armonia e della pace nel mondo” [1-2]. vent’anni dopo la sua realizzazione l’opera si presentava ancora in buono stato, seppur non paragonabile all’aspetto originario. il murale infatti presentava un ingiallimento in tutto il bianco di fondo dello strato preparatorio, uno scolorimento delle linee nere che contornano le figure e una notevole desaturazione delle aree colorate. nel 2011 è stato intrapreso un intervento conservativo focalizzato alla pulitura della superficie pittorica e alla sua protezione dagli agenti atmosferici. una campagna diagnostica a supporto dell’intervento di restauro, finanziato dal progetto copac (conservazione preventiva dell’arte contemporanea), dal comune di pisa e dall’associazione “friends of heritage preservation” (usa), è stata realizzata al fine di comprendere i materiali e il loro stato di degrado. in particolare in questo lavoro vengono riportati i dati acquisiti in situ mediante spettroscopia di riflettanza con fibre ottiche (fors) nell’intervallo spettrale uv-vis-nir [3-4] e colorimetria [5]. le indagini fors sono state principalmente 1veronica marchiafava v.marchiafava@ifac.cnr.it 1giovanni bartolozzi g.bartolozzi@ifac.cnr.it 1costanza cucci c.cucci@ifac.cnr.it 1marco de vita marcodevita@live.it 1marcello picollo m.picollo@ifac.cnr.it 1istituto di fisica applicata “nello carrara” del consiglio nazionale delle ricerche misure di colore per la caratterizzazione e il monitoraggio di opere d’arte contemporanea 2701/14 | cultura e scienza del colore color culture and science l’acquisizione e l’elaborazione degli spettri è stata realizzata mediante software aspect plus®zeiss. lo strumento impiegato per le misure colorimetriche è uno spettrocolorimetro konica-minolta mod. cm700d che lavora con una geometria di misura d/8° e permette di acquisire spettri di riflettanza nell’intervallo 400700 nm sia in riflettanza totale (componente speculare inclusa) sia in sola riflettanza diffusa (componente speculare esclusa). la sorgente interna è una lampada xeno pulsata, mentre il sensore è costituito da fotodiodi al silicio che forniscono un passo di campionamento spettrale di 10 nm. per la taratura del colorimetro sono stati utilizzati un riferimento bianco (superficie riflettente al 100%) e una “trappola di luce” che simula una superficie totalmente assorbente (superficie nera ideale), entrambi in dotazione allo strumento. le misure di colore sono state realizzate in riferimento all’illuminante standard d65, all’osservatore standard 10°, escludendo la componente speculare della radiazione. i dati colorimetrici sono riportati in riferimento allo spazio di colore ciel*a*b* 1976. 3. risultati e discussione 3.1 spettroscopia di riflettanza con fibre ottiche (fors) le misure fors sono state effettuate su piccole aree della superficie pittorica al fine di determinare la tavolozza dei colori impiegati dall’artista (tabella 1). l’analisi del background su cui l’artista ha realizzato l’opera, costituito da un sottile strato di granuli di quarzo con un legante acrilico, ha evidenziato la presenza di un pigmento bianco identificato come biossido di titanio (tio 2 ) della varietà rutilo. infatti gli spettri mostrano un forte assorbimento nella regione al confine tra ultravioletto e visibile, con flesso intorno ai 400 nm, dovuto al band gap tra la banda di valenza e la banda di conduzione, che nel rutilo è di circa 3.0 ev [6]. lo spettro mostra inoltre delle bande di assorbimento abbastanza larghe e poco definite centrate intorno a 1200 nm e a 1950 nm attribuibili alla presenza di acqua adsorbita dalla superficie muraria. le tre bande che si osservano fra 1680 nm e 1770 nm circa sono probabilmente dovute al legante utilizzato (figura 1). la presenza degli assorbimenti del rutilo anche negli spettri acquisiti sulle campiture di colore fa supporre che l’artista lo abbia impiegato in miscela con i colori puri per creare la tonalità desiderata. in tutti gli spettri delle aree colorate sono state individuate inoltre le due bande di assorbimento caratteristiche della caolinite nella regione del vicino infrarosso a 1394 nm e 1414 nm, dovute alla prima overtone dello stretching del gruppo ossidrilico [7]. considerando che gli assorbimenti della caolinite non sono presenti negli spettri acquisiti sul background è ipotizzabile che essa sia presente come inerte soltanto nei colori puri. gli spettri acquisiti sull’area burgundy mostrano due bande di assorbimento a circa 530 nm e 865 nm attribuibili alla presenza di ossidi di ferro (ematite a-fe 2 o 3 ). gli spettri raccolti sulle campiture rosso e rosa mostrano invece l’andamento caratteristico di coloranti organici. in particolare, nella campitura rosso due bande di assorbimento a circa 520 nm e 556 nm permettono di ipotizzare la presenza di quinacridone red [8]. le bande a 498 nm e 535 nm negli spettri acquisiti sulle campiture rosa sono attribuibili invece alla presenza di un colorante arancione, forse tetracene. gli spettri acquisiti sulle campiture giallo mostrano un flesso intorno a 505 nm e un andamento che fa supporre la presenza di un pigmento della famiglia dei gialli arilidici [9]. le misure effettuate sulle campiture verde e blue mostrano spettri con andamento simile, sebbene con assorbimenti in posizioni diverse, che permettono di ipotizzare l’impiego di due pigmenti della stessa natura (figura 2). l’andamento degli spettri è sovrapponibile a quello tipico delle ftalocianine. per quanto riguarda il verde si osservano bande di tabella 1 – elenco dei materiali rilevati con l’indagine fors area pigmento legante inerte background bianco di titanio (rutilo) resina acrilica --burgundy ossidi di ferro/rutilo resina acrilica caolinite rosso rosso quinacridone/rutilo resina acrilica caolinite rosa tetracene/rutilo resina acrilica caolinite giallo giallo arilide/rutilo resina acrilica caolinite verde verde ftalocianina/rutilo resina acrilica caolinite blue blue ftalocianina/rutilo resina acrilica caolinite violetto carbazolo diossazina/rutilo resina acrilica caolinite nero ------28 cultura e scienza del colore color culture and science | 01/14 assorbimento a 450 nm, 650 nm, 730 nm e 780 nm, attribuibili al verde ftalo. per il blue si hanno assorbimenti attribuibili al blu ftalo: due bande di assorbimento a 620 nm e 715 nm circa, con una spalla intorno ai 430 nm, dovute a transizioni p-p*, e altre due bande, a circa 910 nm e 1100 nm, quest’ultima dovuta alla seconda overtone dello stretching del gruppo c-h [10]. infine gli spettri acquisiti sulle campiture di colore viola mostrano tre bande di assorbimento a circa 540 nm, 567 nm e 627 nm che fanno supporre l’utilizzo di un pigmento organico di sintesi a base di carbazolo diossazina [8]. gli spettri di riflettanza uv-vis-nir registrati sulle linee nere delle figure non hanno fornito alcuna informazione sulla composizione chimica dei pigmenti usati dall’artista, a causa della presenza di un forte assorbimento che copre l’intero intervallo spettrale indagato. 3.2 colorimetria le misure di colore sulle diverse campiture (figura 3) sono state focalizzate alla valutazione dell’efficacia della procedura conservativa applicata. l’intera superficie del murale, a esclusione delle linee nere che contornano le figure, è stata sottoposta a un trattamento di pulitura con una miscela acquosa, scaldata a 60°c, di: • agar gel (5 % ), • edta disodico (1%), • carbonato d’ammonio (0.2 %). le linee nere, che mostravano una tendenza a perdere materiale per semplice contatto, sono figura 2 spettri fors delle aree verde (linea verde) e blue (linea blu) figura 3 tuttomondo, particolare delle aree investigate figura 1 spettro fors del background 2901/14 | cultura e scienza del colore color culture and science colore t0 – prima della pulitura t1– dopo la pulitura t2 – dopo il trattamento protettivo t3 – 1 anno dopo l* a* b* l* a* b* l* a* b* l* a* b* area 17 violetto 73.8 1.7 -3.2 73.1 3.8 -12.3 72.6 3.9 -11.9 72.7 3.7 -11.1 area 18 blue 62.6 -9.5 -15.5 57.5 -15.4 -26.8 56.8 -15.6 -26.4 56.1 -15.4 -26.2 area 19 giallo 81.9 2.7 28.4 83.1 1.7 35.9 83.1 2.0 36.3 81.9 1.8 35.2 nero 28.8 0.5 0.2 25.1 0.5 -0.2 24.5 0.5 -0.1 24.3 0.5 0.0 rosa 74.5 18.1 13.5 73.9 23.2 15.4 73.1 24.1 16.1 72.9 23.9 16.3 area 20 verde 70.4 -14.4 4.8 67.7 -22.8 0.8 66.6 -21.8 1.6 66.7 -22.0 1.5 background 78.1 0.9 11.0 78.2 1.0 10.2 79.6 0.8 9.7 79.3 0.9 9.7 burgundy 54.7 17.4 7.7 52.4 21.4 9.3 50.7 20.1 8.8 51.1 20.4 9.4 area 21 rosso 64.9 32.0 10.7 65.0 31.9 10.0 62.7 35.7 11.3 57.7 39.9 12.6 state invece consolidate con una emulsione microacrilica (microacril® imar) diluita al 5% in acqua. su tutta la superficie muraria è stato infine applicato un protettivo alchilalcossisilanico (hydrophase®). le misure di colore, eseguite prima e dopo i trattamenti di pulitura/consolidamento, sono state ripetute dopo l’applicazione del protettivo e un anno dopo l’intervento conservativo. i risultati sono riportati in tabella 2 e 3. dalle analisi effettuate si evince che tutte le aree colorate risultano più sature dopo la pulitura, tranne le campiture background e rosso per le quali non sono state registrate significative variazioni di colore. le aree rosa e violetto hanno mostrato il medesimo comportamento: dopo il trattamento di pulitura si nota un aumento delle coordinate a* e b*, mentre la coordinata l* è rimasta invariata. valori più elevati sono stati registrati per a* e b* nell’area burgundy, che risulta però più scura dopo la pulitura (∆l* ≈ -2). nel caso delle aree blue e verde, tutte le tre coordinate di colore sono diminuite dopo il trattamento. in particolare, le variazioni più significative sono state osservate per b* nell’area blue (∆b* ≈ -11) e per a* nell’area verde (∆a* ≈ -8) risultando, come aspettato, un aumento del grado di blu e del grado di verde, rispettivamente. per l’area giallo sono stati registrati un aumento della coordinata b* (∆b* ≈ 8) e una leggera diminuzione della componente rossa. le linee nere sono diventate più scure e più sature in seguito al trattamento di consolidamento. considerando il trattamento protettivo, le variazioni di colore sono state minime in seguito all’applicazione di hydrophase® con ∆e intorno a 1 (aree violetto, blue, giallo, rosa e nero) o a 2 (aree background, verde e burgundy). solo per l’area rosso è stato registrato un ∆e ≈ 5. infine le analisi colorimetriche ripetute un anno dopo l’intervento conservativo non hanno mostrato variazioni significative tranne che per l’area rosso (∆e ≈7). questo anomalo comportamento dovrà essere ulteriormente investigato al fine di giustificare tali differenze. 4. conclusioni le indagini spettroscopiche e colorimetriche condotte all’interno del progetto conservativo del murale tuttomondo di keith haring sono state eseguite al fine di: • identificare i pigmenti presenti nelle pitture acriliche usate dall’artista; • controllare i valori delle coordinate di cromaticità prima, durante e dopo il trattamento di pulitura delle aree colorate e il consolidamento delle linee nere; • controllare eventuali variazioni dei parametri colorimetrici in seguito al trattamento protettivo; • creare una mappatura di colore al termine del trattamento per fornire valori colorimetrici di riferimento da impiegare durante i processi di manutenzione dell’opera. i risultati fors hanno reso possibile la caratterizzazione tentativa della tavolozza di colori usata dall’artista. la campagna diagnostica ha confermato l’efficacia del trattamento di pulitura che ha indotto variazioni di colore significative in tutta la superficie. infatti, tutti i colori, che risultavano sbiaditi dopo vent’anni di esposizione ambientale, appaiono più saturi e luminosi dopo il trattamento conservativo. il trattamento tabella 2 – valori colorimetrici (l*, a*, b*) per ciascuna area di colore prima (t0), durante (t1 and t2) e dopo l’intervento conservativo tabella 3 – differenze di colore ∆e calcolate per lo spazio ciel*a*b*1976 colore ∆e (t1-t0) ∆e (t2-t1) ∆e (t3-t2) area 17 violetto 9.4 0.6 0.9 area 18 blue 13.7 0.7 0.8 area 19 giallo 7.7 0.4 1.7 nero 3.8 0.6 0.2 rosa 5.5 1.4 0.4 area 20 verde 9.7 1.7 0.3 background 0.8 1.6 0.3 burgundy 4.8 2.2 0.8 area 21 rosso 0.7 4.6 6.6 30 cultura e scienza del colore color culture and science | 01/14 protettivo, invece, non ha indotto variazioni di colore sulla superficie, tranne che per l’area rosso, confermando la caratteristica di buona trasparenza del prodotto. un anno dopo il trattamento conservativo, il murale non ha subito variazioni significative confermando l’efficacia del trattamento prescelto. ringraziamenti il presente lavoro è stato svolto nell’ambito del progetto conservazione preventiva dell’arte contemporanea (copac) finanziato dalla regione toscana (p.a.r. fas 2007-2013 regione toscana linea di azione 1.1.a.3 avviso pubblico regionale 2009 per il sostegno di progetti di ricerca in materia di scienze socio economiche e umane, decreto 155/2010). bibliografia [1] bardelli a., keith haring a pisa: cronaca di un murales, pisa, ets, 2003 [2] barilli a., haring. art dossier, firenze, giunti editore, 2000 [3] aldrovandi a., picollo m., radicati b., i materiali pittorici: analisi di stesure campione mediante spettroscopia in riflettanza nelle regioni dell’ultravioletto, del visibile e del vicino infrarosso, 1998, opd restauro, 10:69-74 [4] bacci m., casini a., lotti f., picollo m., porcinai s., radicati b., stefani l., spettroscopia in riflettanza noninvasiva mediante l’uso di fibre ottiche in metodologie integrate per l’analisi di dipinti, 2003, edizioni progetto, padova, 101-116 [5] brommelle n., colour and conservation, 1955, studies in conservation, vol.2-2:76-85 [6] hunt g.r., salisbury j.w., lenhoff c.j., visible and nearinfrared spectra of minerals and rocks. iii. oxides and hydroxides, modern geology, 1971, vol. 2:195-205 [7] bacci m., bellucci r., cucci c., frosinini c., picollo m., porcinai p radicati b., fiber optics reflectance spectroscopy in the entire vis-ir range: a powerful tool for the non-invasive characterization of paintings, materials research society symposium, proceedings, 2005, vol 852, oo.2.4.1 oo.2.4.6:297-302 [8] johnston-feller r., color science in the examination of museum objects. non destructive procedures, getty conservation institute, los angeles, 2001 [9] schunck r.p., hunger k., hansa®yellows and oranges in lewis p.a., pigment handbook, whileyinterscience, 1:535-546 [10] tomas rubio m., uv-vis-ir spectroscopic characterization of two modern blue pigments: blue phthalocyanine and blue indanthrene, 2006, 1st level master thesis in “materials and diagnostic techniques for cultural heritage”, university of pisa cultura e scienza del colore color culture and science 3303/15 | cultura e scienza del colore color culture and science 1 natalia alekseeva natalia-alekseeva@yandex.ru 2 alessandra cirafici alessandra.cirafici@unina2.it 3 vincenzo paolo senese vincenzopaolo.senese@unina2.it 1 phd in environmental technical physics 2 department of architecture and industrial design «luigi vanvitelli», the second university of naples 3 department of psychology, the second university of naples interaction of color scheme and noise in the metro interior. multisensory evaluation and subjective testing 1. introduction acoustics is an important component determining the passenger satisfaction. recently several attempts to assess acoustic comfort aboard rail transport were carried out. most of them were focused on acoustic parameters and subjective annoyance [14]. generally during the tests participants were seated in a laboratory room and listened to prerecorded metro or high speed trains sounds, presented through loudspeakers or headphones, indicating their opinion. usually they were asked to imagine being aboard [3] while seated in a laboratory room [5]. however, these procedures reproduce environmental information in a simplified way and do not take into account the multisensory nature of human perception: sounds are presented to participants without contextual visual scenarios. there is a large body of research showing that vision and audition instead of being independent modalities interact in complex ways [6 8]. in our previous study [9] we have seen that visual components seem to modulate the impact of noise on cognitive performances and self-report evaluations. as regards the sound intensity assessment, some researches have shown that visual factors, such as colors, can modulate loudness judgments. for example, colors like red or pink seem to increase perceived loudness, whereas grey or pale green seem to decrease it [10]. in another study, instead, no influence of train color on loudness evaluation was found [11]. in this paper, the investigation of the acoustic comfort on board metros is described. a large segment of the research is devoted to the experimental analysis and evaluation of the interaction between the metro car interior color and noise perception through the use of innovative technology of virtual reality and subjective tests. the article will cover following steps of the research: • survey of existing metro interior colors, • interior chromatic solutions design and selection, • audio stimuli selection for the experiment, • virtual reality design for experiment, • immersive virtual reality experiments, • data analysis and conclusions. 2. survey of existing metro interior colors first of all, to study a current situation of colors utilization inside metro cars, a survey on 150 existing metros was fulfilled. the interior photographs of metro carriages from all over the world were downloaded from the official sources websites of metros. the survey has shown that in most cases white color was used for the internal side panels, white or grey colors were prevalent for the metro doors (figure 1); dark tints were used on the floor of carriages: grey, brown, dark blue, black; while the variety of colors were utilized for the chairs: brown, green, black, grey, red and blue, the last one was the most used (30% of metros). as for the accessories, the yellow color is added to the majority of neutral grey and white hues. that is done considering the needs of visually impaired passengers in order to clearly identify important accessories, such as railings, with strong color contrasts. the conducted survey has shown that not always the interior colors were fairly equilibrated between each other, especially as regards the old metros. the preference of neutral hues choice abstract in this paper the results of research, aimed at investigation of the acoustic comfort on board of urban transport systems are presented. a large segment of the research is devoted to the experimental analysis and evaluation of the interaction between the metro car interior color and noise perception, through the use of virtual reality and subjective tests. several studies showed that vision and audition instead of being independent modalities interact in complex ways. the results of this research showed that, despite of expectations of the interaction of sound and colors impacts on personal judgments, evaluations given to the interior colors were influenced only by the color scheme. sound environment perception was influenced only by the noise factor. 34 cultura e scienza del colore color culture and science | 03/15 for most elements seems to be quite traditional. it could be caused by the specific materials availability and practicalness, as well as the desirable in public transport means sensation of calmness. but in some cases the neutral colors could evoke the sensation of boredom. therefore it is necessary to fulfill a subjective evaluation of the internal scenarios. for the research goals it was decided to create several not very typical chromatic dimensions to investigate the reactions of people and to estimate their visual, acoustic and complex comfort. 3. interior chromatic solutions design and selection to propose new interior chromatic solutions for the immersive virtual reality (ivr) tests, a wide study was performed. forty color palettes from the guidebook [12] were taken as a starting material. they were thoroughly examined on kind of sensations and psychological reactions the different colors combinations should evoke in the people’s mind (e.g. calmness or vivacity). figure 1 statistics on side panel (left picture) and doors (right picture) colors used in the metro interiors table 1 elaborated color schemes 3503/15 | cultura e scienza del colore color culture and science the practicalness and adequacy of their use in the metro environment was also considered. more than thirty design solutions were elaborated by means of photoshop. the pictures of simulations were proposed to design experts and to ordinary people to get their judgments and suggestions. finally, four color palettes were selected: tranquil, innovative, corporative and multicultural. selecting the colors from these chromatic palettes, several color schemes were elaborated for the metro experiments. considering the security needs, the exit from the car was always emphasized by the doors or other elements color that differed from the side panels. four chromatic dimensions chosen for the test are represented in the table 1[12]. 4. audio stimuli for the experiment binaural audio signals (16 bit/44.1 khz) which were recorded by a portable two-channel device “m-audio microtrack 24/96” and binaural headphones “sennheiser noise gard hdc 451” during the trips in world great cities’ metros were used as basic acoustic material for the test. three soundtracks with different loudness were chosen for this experiment: the quietest one, berlin s3, which was however characterized by the presence of soft rattling noise; the noise of turin val, belonging to the rubber-tyred metro systems, and the loudest one, naples l1. the parts of soundtracks between two successive stations, with duration approximately one minute, were extracted from the original sound records of these three metro lines. each soundtrack was analyzed in terms of equivalent noise level (leq), loudness (n), 5 percentile loudness (n5), sharpness (s), roughness (r) and fluctuation strength (fs), and psychoacoustic annoyance (pa) [13] was calculated for each track, the data are reported in table 2. values are the average of the left and right channels. table 1 elaborated color schemes 36 cultura e scienza del colore color culture and science | 03/15 5. virtual reality design for experiment 3d graphic virtual reality scenarios of a metro and platform were created. the graphic model was designed by means of google sketchup 7.0 software, simulating geometrical constructions according to actual dimensions, and elaborated color schemes. the virtual metro train was composed of two coaches attached to each other. along the virtual platform several avatars simulated passengers waiting for the train. in the metro coaches some avatars appeared seated and some were standing (figure 2). the wordviz software for virtual reality development allowed the simulation of the train movement, opening/ closing of doors and the changing of environment outside the metro coach during the tunnel passage. as well, the sounds from the chosen tracks of acoustic signals were inserted. twelve virtual scenarios were organized to test all the combinations of color schemes and noises (four color schemes vs. three noise tracks). following names were given to the color schemes for convenience: the first color scheme – beige, the second one – blue, the third – yellow and the fourth – red. 6. immersive virtual reality experiments 6.1. experiment location and instrumentation the ivr experiments were carried out in the built environment control laboratory ri.a.s. of the second university of naples, in a room arranged for the ivr subjective testing (figure 3). the ivr set includes a work station supplied with software vizard 4.0 and linked to the following devices: emagin z800 3dvisor, polhemus patriot, position tracking and 3d digitalizing system and pioneer bass boost headphones. 6.2. test procedure during the test participants were submitted to twelve scenarios, described supra, representing virtual journeys between two metro stations. before starting the test, participants were asked to pay attention to the color schemes of the interiors and sounds they perceive, and feeling of comfort or discomfort they got. during the journey they could seat or stand, turning the head and moving normally in the virtual environment. the order of presentation of the scenarios was quasi-randomized and counterbalanced within table 2 characteristics of noise tracks chosen for the experiment. noise track leq, db(a) n, sonegf n5, sone s, acum r, casper fs, cvasil pa 1. berlin s3 64,10 15,56 20,92 0,99 25,29 24,44 24,29 2. naples l1 80,53 35,96 64,33 1,05 30,86 39,73 73,45 3. turin val 73,45 30,10 37,23 1,19 28,12 22,34 42,16 figure 2 a metro train model designed in google sketchup (section). figure 3 participants in the laboratory of ivr testing. 3703/15 | cultura e scienza del colore color culture and science each subject and across subjects. at the end of each scenario participants were required to fill in a self-report questionnaire in microsoft excel. in this questionnaire they expressed their judgements on the interior colors, sounds and overall atmosphere, estimating sound volume and annoyance. 6.3 subjective assessment the subjective assessment of every scenario was fulfilled by means of specially elaborated questionnaire in italian, divided into the following categories: interior colors assessment, sound volume rating and sound annoyance rating, and overall opinion of the scenario environment. the interior colors assessment and overall assessment were carried out by means of semantic differentials (sds). several seven-point bipolar scales were elaborated for the description of sensations provoked by the metro. participants chose the correct ones according to their ratings from the window of multiple choice. the sound volume and noise annoyance of each scenario was evaluated by means of the scrollbar on which the participants could choose the value corresponding to their opinion. the sound volume was quantified from 0 («very low») to 100 («very high»), and sound annoyance was quantified from 0 («not at all») to 100 («greatly»). 6.4. participants description 32 persons (16 males and 16 females) recruited from the students and personnel of the second university of naples participated voluntarily in the study. mean age of the participants was 25.4, sd = 3.9 (range 19 to 42 years). all participants reported normal hearing and normal or corrected to normal vision. 7. data analysis 7.1. interior colors assessment the mean values of the sds estimating internal colors are represented on the graphs in the table 3. the scores of all three metros were averaged. to analyze the effects of scenarios on mean values of six sd internal colors assessments, two 3×4 anovas that treated noise as threelevel within-subject factor and color as fourlevel within-subject factor, was carried out. the results showed that no one of the sd variables was influenced by the metro noise factor: d1: f(2, 9) = 1.71, p = .24; d2: f(2, 9) =0.47, p = .64; d3: f(2, 9) =0.55, p = .59; d4: f(2, 9) =0.28, p =.76; d5: f(2, 9) = 0.23, p = .80; d6: f(2, 9) = 0.60, p =.57. the semantic differentials were influenced by the color scheme. the analysis revealed that: the beige metro was judged more relaxing than blue one; beige color scheme was more harmonious than blue and yellow, and red color scheme was evaluated as more harmonious than blue one. beige metro was more equilibrated than blue and yellow, beige and red metros were assessed as more adequate than blue, and, finally, red color scheme was rated as more familiar than beige and yellow ones. figure 4 mean values of subjective assessments of sound volume and annoyance for three metro noises figure 5 mean values of subjective assessments of sound volume and annoyance for four color schemes 38 cultura e scienza del colore color culture and science | 03/15 7.2. estimations of sound volume and sound annoyance on the figure 4 the average for four color schemes values of sound volume (left) and annoyance (right) estimation of three metros are depicted by means of box-plot diagrams. from these diagrams we see that the assessment seems to be strongly correlated with leq. the average values of these assessments for four color schemes, cumulative for all metros are represented on the figure 5. to analyze main and interactive effects of table 3 mean values of semantic differentials for overall metro environment assessment. 3903/15 | cultura e scienza del colore color culture and science scenarios on subjectively assessed sound volume and annoyance, two mixed factorial 4×3 anovas that treated a color scheme as fourlevel within-subject factor and metro noises as three-level within-subject factor was carried out. the results showed that sound volume was influenced only by the noise factor f (2, 62) = 84.50, p<.001, η p 2 = 0.73. there was no color scheme effect f (3, 93) = 0.526, p = .665, η p 2 = .017. the effect of the noise-color interaction was not found f (6, 186) = 0.852, p = .532, η p 2 = .027. and similarly, for the sound annoyance, the results showed that it was influenced only by the noise factor f (2, 62) = 46.52, p<.001, η p 2 = 0.60. there was no color scheme effect f (3, 93) = 0.97, p = .41, η p 2 = .03. the effect of the noise-color interaction was not found f (6, 186) = 0.24, p = .96, η p 2 = .008. 7.3. estimations of overall environment the scores for the sds estimating overall environment are represented on the graphs in the table 3. in the left column of the table values, averaged as a function of metro are depicted, while in the right one the values averaged as a function of colors are given. so we can easily see, for example, that metros with color scheme number 4, called «red» were judged as more stimulating, while metro environments characterized by the naples’ metro noise, were assessed as more unpleasant and uncomfortable then others. to analyze main and interactive effects of scenarios on overall metro environment estimation, a mixed factorial 4×3×2 anova that treated a color scheme as four-level withinsubject factor, metro noises as three-level within-subject factor and gender of participants as two-level between subject factor, was carried out. the results showed that the assessments of comfort, beauty, pleasantness, and coziness were influenced by the noise factor. in all these cases the naples metro ratings were lower than those of berlin and turin. instead, the assessment of stimulation was influenced by the color factor. the beige metro was judged as the most boring. 8. conclusions the results showed that evaluations, given to the interior colors were influenced only by the color scheme. sound volume and sound annoyance estimations were influenced only by the noise factor. the overall metro environment assessments of comfort, beauty, pleasantness, and coziness were influenced by the noise factor, while stimulation was influenced by the color factor. the beige metro was judged as the most boring. in all these cases the naples metro ratings were lower than those of berlin and turin. no gender effect on overall metro environment estimation was discovered. bibliography [1] h. fastl. psycho-acoustics and sound quality. in j. blauert (ed.), communication acoustics (chapter 6). berlin: springer, 2005; [2] a. e. j. hardy. measurement and assessment of noise within passenger trains. journal of sound and vibration, 231(3), 2000, pp. 819-829; [3] s. kuwano, s. namba, t. okamoto. psychological evaluation of sound environment in a compartment of a high-speed train. journal of sound and vibration, 227, 2004, pp. 491-500; [4] e. parizet, n. hamzaoui, j. jacquemoud. noise assessment in a high-speed train. applied acoustics, 63, 2002, pp. 1109-1124; [5] g. r watts. a comparison of noise measures for assessing vehicle noisiness. journal of sound and vibration, 180(3), 1995, pp. 493-512; [6] f. frassinetti, n. bolognini, e. ladavas. enhancement of visual perception by crossmodal visuo-auditory interaction. experimental brain research, 147, 2002, 332343; [7] l. shams, r. kim. crossmodal influences on visual perception. physics of life review, 7, 2010, pp. 269-284; [8] d. h.warren, t. j. mccarthy, welch, r. b. discrepancy and nondiscrepancy methods of assessing visual-auditory interaction. attention, perception, & psychophysics, 33(5), 1983, pp. 413419; [9] n. alexeeva, m. masullo, f. ruotolo, v. p. senese. comparison of audio-only and audio-video approaches to acoustic discomfort assessment in public transportation systems. in proceedings of forum acusticum 2011, aalborg, denmark, 27 june-1 july 2011, p: 6; [10] d. menzel, h. fastl, r. graf, j. hellbrück. influence of vehicle color on loudness judgments. the journal of the acoustical society of america, 123(5), 2008, pp. 24772479; [11] e. parizet, v. koehl, influence of train colour on loudness judgments. acta acustica united with acustica, volume 97, number 2, march/april 2011 , pp. 347-349(3); [12] t. samara. guida agli stili tipografici. spunti per la scelta dei caratteri nella grafica e nel design. il castello srl, trezzano sul naviglio, 2006; [13] h. fastl, e. zwicker, psychoacoustics. facts and models (3rd edition). berlin, germany: springer series in information sciences, 2007; [14] m. bisson, c. boeri, variazioni sul colore, franco angeli, milano,2006; [15] l. luzzatto, r. pampas, il colore persuasivo, il castello milano, 2001; [16] l. sivik, c. taft, on studyng colour combinations : some reflexions and preliminary experiments, university of goteborg, psycolofical reports vol 19, 1989; [17] l. sivik, c. taft, colour combinations and associated meanings: semantic dimension and color chords, university of goteborg, psycolofical reports vol 22, 1992. cultura e scienza del colore color culture and science 2702/14 | cultura e scienza del colore color culture and science valutando lo scarto dell’indice all’interno di aree omogenee e correlandolo agli stati di degrado superficiale valutati di caso in caso. a questo primo approccio sono seguiti ulteriori casi studio in cui sono state realizzate prese omologhe di scansioni laser e panoramiche all’infrarosso (chiesa di san filippo). il nostro emettitore laser a impulsi, leica c10, genera un fascio nello spettro del visibile con l pari a 532 nm. il valore di riflettanza acquisito non può essere, nella maggior parte dei casi, confrontato in termini assoluti, ma valutando e controllando le variabili ambientali è possibile ricavarne conclusioni in merito allo stato di degrado del materiale in esame. dal confronto con la termografia è possibile validare tali risultati per la realizzazione di mappe tematiche di degrado. la loro applicazione permette di rintracciare distacchi di intonaco, aree a rischio per contenuti di umidità non visibili, dilavamento, salinità delle murature sottostanti etc. le indagini visive finora utilizzate nella diagnosi dello stato di degrado superficiale possono ora servirsi di tali strumentazioni per una valutazione analitica dei meccanismi di degrado, con una metodologia di indagine speditiva e acquisibile nella fase di rilievo metrico. 2. stato dell’arte nel rilievo architettonico il laser scanner terrestre (tls) è la tecnologia d’elezione; il remote sensing viene sfruttato in aggiunta o a integrazione di test non distruttivi. sia nelle analisi sia nelle fasi di monitoraggio, diversi studi utilizzano tale strumentazione in geologia e geofisica [1], nel controllo del degrado da inquinamento atmosferico mediante telerilevamento aereo [2], per lo studio e la caratterizzazione di statue [3]. ampia letteratura indaga i punti di forza e di debolezza dei tls, identifica cause e fonti di errore e analizza potenziali usi degli output. i dati lidar (terrestri e non) vengono utilizzati per la quantificazione e il monitoraggio del deterioramento di superfici architettoniche o archeologiche, ma anche per generare modelli 3d utili nella comunicazione delle informazioni [4]. l’uso dei dati di riflettanza da laser scanner è tuttora campo di sperimentazione e ricerca. sembra possibile ottenere informazioni sullo stato delle discontinuità superficiali di monumenti 1. introduzione le nuove tecnologie laser scanning “all in one” applicate al rilievo architettonico si stanno dimostrando efficaci, flessibili, economiche e speditive permettendo l’acquisizione, all’interno di prese omologhe, di differenti tipi di dati. la letteratura a riguardo è ampia e descrive dettagliatamente le potenzialità nel rilevamento morfologico, materico e anche colorimetrico dei manufatti. le ormai note tecniche di mappatura delle immagini fotografiche alla nuvola di punti consentono di completare punto per punto il dato spaziale col dato colore (rgb), in fotografie hr. di supporto alla buona lettura della superficie, l’operatore si serve del valore di riflettanza (r), generando delle mappe graduate che consentono il riconoscimento visivo degli elementi scansionati. ne consegue che il concetto di modello solido applicato alle più “recenti” nuvole di punti può aggiornarsi nel considerare il modello stesso come un vero e proprio sistema informativo del manufatto in cui i livelli di analisi si integrano restituendo nel contempo esiti morfologici, geometrici, colorimetrici e materici. quello della riflettanza è, in questo senso, forse il dato meno indagato. l’intento di questa ricerca è di dimostrare come il dato di riflettanza da rilevamento scanner laser possa essere (in particolari condizioni) comparato a quello ottenibile da prove non distruttive comunemente applicate ai beni artistici, integrandone gli esiti con i dati qualitativamente rilevanti di carattere metrico, morfologico e geometrico restituiti dallo strumento laser. il valore aggiunto, non trascurabile, è avere ampie portate dello strumento (fino a 300 metri), con notevoli potenzialità quindi nell’ispezione di superfici di difficile accesso. in letteratura si dimostra che le variabili maggiormente influenti su r sono l’angolo di incidenza e l’indice di rifrazione del materiale, quest’ultimo determinato dalla microstruttura dello stesso. pur nella consapevolezza che nel nostro campo di applicazione entrano in gioco anche la distanza dall’oggetto e la scabrezza della superficie, è possibile ottenere valutazioni comparate dei dati che indirizzino le più opportune prove diagnostiche dirette. le prime superfici indagate sono state quelle intonacate di villa trissino a cricoli, vicenza. e’ stata condotta un’analisi comparata relativa, paolo clini p.clini@univpm.it ramona quattrini r.quattrini@univpm.it romina nespeca r.nespeca@univpm.it luigi sagone l.sagone@univpm.it dipartimento dicea, università politecnica delle marche, colore, riflettanza e temperatura. dal caso studio di villa trissino a nuove applicazioni integrate di dati lidar terrestri per il rilievo e la diagnostica 28 cultura e scienza del colore color culture and science | 02/14 storici o nel campo della meccanica delle rocce [5]. nell’uso di questi dati è importante gestire e correggere, se necessario, la precisione e l’influenza della distanza dell’oggetto, la sua rugosità o l’angolo di inclinazione [6]. le immagini a infrarossi e termografiche sono molto spesso utilizzate nella diagnostica, nel monitoraggio e nel restauro del patrimonio culturale [7]. esse mostrano l’energia emessa da un materiale (prova della sua temperatura), che può essere rilevata a distanza e utilizzata per definire la distribuzione termica. la termografia del materiale testato, ottenuto attraverso l’elaborazione di segnali ottici catturati da dispositivi sensibili alla radiazione infrarossa, offre informazioni sulle strutture stratificate, sulla presenza di materiali diversi, sulla umidità o salinità della muratura [8]. questo non è sufficiente per l’analisi dei materiali ma, in associazione con altri test non distruttivi, i dati raccolti vengono poi elaborati per produrre schede appropriate per descrivere le proprietà ottiche e visive dei materiali studiati. questo porta ad una mappatura delle antiche proprietà dei materiali [9]. il crescente utilizzo di immagini a infrarossi spinge inoltre i ricercatori a migliorare gli algoritmi di elaborazione sulle immagini termiche per la rilevazione di difetti superficiali [10]. recenti studi hanno dimostrato la corrispondenza tra i danni causati dal sisma e precedenti analisi basate sulla termografia. questo ci indica un’ulteriore conferma sulla possibilità di utilizzare i termogrammi in diversi campi della diagnostica architettonica [11]. 3. analisi attraverso mappe di riflettanza. il caso studio di villa trissino a cricoli ancora oggi le acquisizioni laser scanning consentono principalmente analisi morfometriche; la ricerca su villa trissino a cricoli introduce un approccio per la lettura del degrado materico e l’analisi a occhio nudo di sotto-strati invisibili. inoltre, un’indagine qualitativa su superfici intonacate consente di ottenere ulteriori elementi di datazione per le murature dell’edificio e di valutare il valore storico dell’intonaco (figura 1). la campagna di rilievo è stata condotta nel mese di ottobre 2011 con il laser scanner leica c10, con spot luminoso verde pari a l=532 nm. durante la fase di rilevamento, abbiamo organizzato 6 stazioni, 20 scansioni (max griglia 1 mm a 20 m). dopo l’allineamento e la riduzione delle ridondanze, abbiamo ottenuto una registrazione della nuvola con 84 mln di punti (errore rms 2 mm). il nostro studio si focalizza sullo sfruttamento delle immagini hue intensity, cosiddette “mappe di riflettanza”. l’uso del valore di riflettanza, acquisito punto per punto, genera analisi visive che sono più performanti rispetto alla acquisizione fotografica e al relativo valore rgb. se la griglia di acquisizione è accurata, possiamo apprezzare differenze sostanziali su materiali omogenei [14]. per esempio, nella facciata principale intonacata, sono facilmente visibili in mappa di riflettanza, le differenze tra le torri e il blocco centrale, che non si percepiscono figura 1–villa trissino a cricoli: fronte sud. a) disegno da www.epalladio. com b) foto ad alta risoluzione. 2902/14 | cultura e scienza del colore color culture and science dalla fotografia (figura 2 a-b). inoltre i vantaggi dell’uso della riflettanza sono evidenti in assenza di luce o nell’annullamento dell’influenza della luce, delle ombre o delle zone sovraesposte sul valore di intensità (figura 2 c-d-e-f). i software di gestione della nuvola di punti facilitano la rappresentazione e il conseguente uso del valore di riflettanza, grazie alla gamma di tonalità di assegnazione che può essere personalizzata per sottolineare zone interessanti. lavorare su intervalli limitati può mettere in luce specifiche parti o fenomeni. l’output dei dati permette query interattive in ambiente proprietario cyclone: utilizzando gli figura 2 – a) e b) villa trissino a cricoli: fronte sud. comparazione tra ortofoto e mappa di riflettanza in range personalizzato. c) d) e) f) mappe di riflettanza della facciata sud. comparazione tra ranges monocromatici figura 3 – a) b) c) mappe di riflettanza in multi-hue intensity della facciata ovest. comparazione di tre ranges personalizzati. d) e) dettaglio del fronte sud: mappa di riflettanza in multi-hue intensity, confronto rainbow e blgrbror. f) valore di riflettanza nella palette “point cloud info”. g) h) dettaglio del fronte sud: confronto tra mappa di riflettanza multi-hue e immagine rgb 30 cultura e scienza del colore color culture and science | 02/14 strumenti sw per la gestione della nuvola di punti, è possibile effettuare la lettura del valore numerico ed estrarre i dati aggregati (figura 3). un altro uso interessante è quello dell’editor truview, dove la corrispondenza tra forma e r può essere vista direttamente dalla nuvola di punti, in ambiente html open source lato client. questo fatto allarga il campo sfruttamento del ddm (digital dense model) ai non esperti di rilievo. dopo l’esame visivo, l’esportazione di 2d (ortoimmagine in mappa di riflettanza) consente una facile mappatura del degrado materico e facilita nella restituzione di disegni utilizzati tradizionalmente nel rilievo finalizzato al restauro (figura 4). una lettura critica delle acquisizioni è necessaria per sviluppare un’analisi di tipo quantitativo: prima di tutto una singola scansione garantisce un’affidabilità migliore nel confronto dei valori di r tra aree omogenee. in realtà la questione principale, utilizzando diverse scansioni (modello allineato), è la variabilità della distanza della stazione e dell’angolo di inclinazione del raggio. abbiamo organizzato lo studio delle mappe di riflettanza sul fronte principale della villa con i seguenti passi: scelta della griglia di forma quadrangolare, identificazione massimi e minimi in aree simili, calcolo della media. la gamma di variabilità della r, espressa in percentuale, è 20-40 per le torri, mentre per il corpo centrale è 20-50. la distanza di acquisizione, che va da 15 mt (parte inferiore) a 25 mt (parte superiore), non mostra influenze apprezzabili. questi dati risultano coerenti con spettri di laboratorio in letteratura [11], da cui risulta un valore di riflettanza totale (corrispondente a l= 532 nm) pari a 25% per l’intonaco di calce ocra giallo. non è possibile ottenere risultati attendibili sulla natura dei materiali tramite i valori r; tuttavia con il potenziamento della ricerca in questo campo ci si può aspettare la codifica delle risposte di materiali diversi. il metodo che qui suggeriamo genera datasets integrati per navigare, anche in modo dinamico, i modelli di rilievo architettonico: queste analisi sono utili e facili da impiegare. figura 4 –villa trissino a cricoli: fronte sud. disegni 2d di mappatura del degrado 3102/14 | cultura e scienza del colore color culture and science 4. integrazioni tra mappe di riflettanza e immagini termografiche. il caso studio della chiesa di san filippo a cagli l’impiego della termografia all’infrarosso in edilizia non è principalmente rivolto alla determinazione dell’umidità nelle murature, quanto piuttosto alla valutazione delle prestazioni di isolamento termico dell’edificio in esame. tuttavia si è visto che tale sistema permette di individuare la presenza di umidità con la mappatura delle aree. si presenta come un metodo indiretto, no-contact, perfettamente in linea quindi con l’idea di rilievo nel campo della diagnostica e del restauro di manufatti storici. il principio si basa sulla misurazione della distribuzione di temperature superficiali di un oggetto. un’anomalia nella distribuzione di temperature è indice di un possibile difetto, che sia esso un ponte termico, un distaccamento di intonaco, un materiale differente o la presenza di acqua all’interno della muratura. si può affermare quindi che la termografia ha il vantaggio di essere un metodo non distruttivo molto efficace e di fornire una rapida lettura delle aree interessate da fenomeni di risalita capillare. l’obiettivo di questo caso studio era la messa a punto di una procedura ad hoc di integrazione dei dati tale da creare un sistema informativo multilayer per l’analisi e la diagnosi. primo risultato di questa sovrapposizione è la possibilità di operare una diagnostica preliminare tramite valore di riflettanza in situazioni di umidità evidente riscontrate a livello visivo prima, e con l’aiuto della termocamera poi. naturalmente questa esperienza è concepita per fare una valutazione qualitativa riguardo una possibile correlazione tra variazioni di riflettanza in presenza di infiltrazioni di acqua. va ricordato infatti che, operando su una porzione di un edificio storico, in condizione reali non controllate in regime di temperatura stazionario, non è possibile ottenere risultati quantitativi. il manufatto in oggetto è chiuso al pubblico dal 16 febbraio 2012 per presunti danni provocati da abbondanti nevicate. in questo edificio monumentale di proprietà ecclesiastica oltre alle lesioni molto marcate su archi portanti, volte, controfacciata e cornicioni sono presenti copiose infiltrazioni d’acqua piovana che interessano in particolar modo la cupola (figura 5). gli strumenti utilizzati sono stati il laser scanner leica c10 e la termocamera infratec variocam hd, la cui risoluzione di 1024 x 768 pixel soddisfaceva al meglio le nostre esigenze. l’area scelta per l’acquisizione è quella maggiormente interessata dai fenomeni di degrado superficiale, al di sotto della cupola. la scelta del posizionamento della presa laser ha mirato alla riduzione delle zone d’ombra valutando adeguatamente l’angolo presa, in modo da garantire la copertura della maggior parte dell’area interessata. la griglia di scansione utilizzata doveva garantire una buona confidenza con l’oggetto e con la risoluzione dei termogrammi. per ottimizzare la mappatura si è deciso di realizzare un’acquisizione termografica a panoramica sferica con centro nodale collimato al centro di presa laser, posizionando i due dispositivi sul medesimo cavalletto tripode e utilizzando la testa sferica nodal ninja 3 (figura 5). prima dell’acquisizione in sito è stata necessaria una calibrazione dei macchinari in laboratorio. la testa sferica compensa in quota la posizione della termocamera e tramite le slitte di traslazione nei tre assi vengono calibrate le rotazioni yaw, pitch e roll per evitare l’errore di parallasse. vanno poi determinati gli angoli di rotazione, verticale figura 5 – (in alto) chiesa di san filippo a cagli: foto della cupola in cui emerge il degrado dovuto alla presenza di infiltrazioni. (in basso) acquisizioni su tripode con laser scanner e termocamera. 32 cultura e scienza del colore color culture and science | 02/14 e orizzontale, che garantiscano un adeguato overlap fra gli scatti. in questo caso, si è scelto di acquisire prese orizzontali ogni 15° e prese verticali ogni 20°, a cui aggiungere scatti verticali a 90° e a -90°, in modo da coprire completamente la sfera. l’elaborazione dei dati provenienti dalla scansione laser è affidata al software leica cyclone. il processo di mappatura e sovrapposizione dei termogrammi e delle mappe di riflettanza, ha richiesto numerosi fasi e l’utilizzo di diversi software di unione e trasformazione delle immagini. la prima fase è stata quella di esportare i termogrammi in formato bitmap in falsi colori (successivamente in scala di grigi) ed eseguire il montaggio delle varie immagini termografiche con il programma di stitching, ptgui pro. ottenuta l’immagine equirettangolare, è stata poi trasformata in cubica con pano2 vr per l’importazione in cyclone (figura 6). ponendosi in una modalità di triplice lettura si hanno a disposizione diversi layers sovrapposti in cui poter registrare delle variazioni cromatiche (figura 7). nel caso a è possibile osservare che il degrado, come si evince dall’immagine fotografica, è molto evidente: ci sono numerosi distacchi dell’intonaco dovuti a infiltrazioni di acque meteoriche. correlando l’esame visivo fotografico con l’esame delle variazioni in falsi colori della mappe di riflettanza si può notare come le variazioni di intensità della riflettanza ricalcano in maniera molto fedele l’andamento del degrado. dalla lettura termografica, invece, la parte esaminata risulta abbastanza omogenea, non sembrano esserci variazioni di temperatura. questo ci fa ipotizzare che, nonostante le infiltrazioni di umidità ci siano state e abbiano causato il distacco dell’intonaco in passato, al momento della presa la parte delle vele sotto la volta risulta asciutta. in questo caso la variazione di riflettanza è strettamente correlata alla variazione colorimetrica dovuta al degrado superficiale. nel caso b, la lettura su più livelli ci fornisce delle informazioni diagnostiche differenti. stando alla sola immagine fotografica di una delle paraste sotto la volta si poteva dedurre che fosse una zona priva di particolari fattori a rischio. grazie ai dati provenienti dalla termocamera, validati dalle variazioni di riflettanza laser, si può ipotizzare invece la presenza di umidità non visibile in superficie. si dimostra, quindi, come l’integrazione di dati geometrici e termici consente l’individuazione di zone a rischio di degrado superficiale a fronte della presenza di umidità invisibile ad occhio nudo. 5. conclusioni la presente metodologia di studio sviluppa un approccio interattivo di conoscenza e analisi degli edifici antichi, permettendo di ottenere informazioni essenziali per l’intervento di recupero e restauro. il rilievo monostrumentale così condotto comprende anche una fase diagnostica sul manufatto nel suo complesso, indagandone tutti gli aspetti metrici, morfologici, materici e di degrado. fornire letture multilayer, così come quelle presentate in questo studio, è un’opportunità straordinaria per una corretta e più accurata individuazione degli effetti del degrado di un manufatto storico. figura 6 – (in alto) equirettangolare completa da acquisizione termocamera in scala di grigi. (in basso) prima prova di mappatura della nuvola di punti nel software cyclone. l’immagine termica colorata inquadra la sola area nei pressi della cupola, ma è stata acquisita ed inserita come panoramica sferica in proiezione cubica. la nuvola di punti è visualizzata in scala di grigio nella sezione a sinistra e in alto a destra, in falsi colori di riflettanza in basso a destra. 3302/14 | cultura e scienza del colore color culture and science l’indagine sulle cause rimane affidata a analisi specifiche. ma l’innovatività del presente approccio consiste nel basso costo, nella molteplicità dei dati e nella loro accuratezza, che possono indirizzare le scelte più opportune per test a contatto e/o prove distruttive, su aree più ristrette e mirate, con il vantaggio di circoscrivere il campo di indagine e ridurre le fasi in situ, attraverso il massimo sfruttamento degli output del rilievo. ringraziamenti si ringrazia il cisa palladio (direttore guido beltramini) e il sig. vittorio trettenero, proprietario di villa trissino, per aver permesso le acquisizioni laser. il rilievo è stato realizzato all’interno del progetto palladio library, promosso da cisa palladio e finanziato da arcus (responsabile scientifico: marco gaiani). il caso studio della chiesa di san filippo a cagli è stato oggetto della tesi di laurea di maria elena marani, relatore prof. paolo clini, correlatore prof. marco d’orazio; alcune delle fasi sperimentali sono state condotte con la collaborazione del prof. nicola paone e del dott. edoardo copertaro. bibliografia [1] p.o. gold, e. cowgill, o. kreylos, r.d. gold, “a terrestrial lidar-based workflow for determining three-dimensional slip vectors and associated uncertainties”, geosphere, volume 8, issue 2, pp. 431-442, 2012. [2] k. themistocleous, a. nisantzi, a. agapiou, d. d. alexakis, d. g. hadjimitsis, v. lysandrou, s. perdikou, a. retalis, n. chrysoulakis, “long term monitoring of air pollution on monuments and cultural heritage sites in cyprus using satellite remote sensing”, international journal of heritage in the digital era volume 1, number 1 / march 2012. [3] c. e. wittich, t. c. hutchinson, r. l. wood, f. kuester, “a methodology for integrative documentation and characterization of culturally important statues to support seismic analysis”, progress in cultural heritage preservation lecture notes in computer science, volume 7616, pp 825-832, 2012. [4] j. kotte, “an investigation of quantifying and monitoring stone surface deterioration using three dimensional laser scanning”, scholarly commons, repository.upenn.edu/ hp_theses/128, 2009. [5] m. zimbardo, “valutazione dell’alterazione con laser scanner negli ammassi a struttura orientata e nella diagnostica dei beni monumentali”, meccanica dei materiali e delle strutture, 2011. [6] f. coren, d. visintini, m. balzani, p. sterzai, g. prearo, f. uccelli, “un algoritmo per la correzione radiometrica di dati laser terrestri”, asita conference proceedings 2005, catania; 11/2005. [7] rizzi a. et al., 2007 (b), “digital preservation, documentation and analysis of paintings, monuments and large cultural heritage with infrared technology, digital cameras and range sensors” , proceedings of the xxi cipa conference “anticipating the future of cultural past”, held in athens, greece, 1-6 october 2007. [8] avdelidis n. p., moropoulou a., 2004, “applications of infrared thermography for the investigation of historic structures”, journal of cultural heritage, vol. 5, pp. 119 – 127. [9] f. gugliermetti, f. bisegna, l. monti, “the “id card” of ancient materials: spectral signature, colour and thermal analysis. a tool for the monitoring and conservation of the archaeological heritage”, journal of the international colour association 8, 68-75, 2012 [10] y. huang, j. w. wu, “infrared thermal image segmentations employing the multilayer level set method for non-destructive evaluation of layered structures”, ndt&e international 43, 34–44, 2010 [11] d.paoletti, d.ambrosini, s.sfarra, f. bisegna, “preventive thermographic diagnosis of historical buildings for consolidation”, journal of cultural heritage 14 (2013) pp. 116–121 [12] g. beltramini, p. guidolotti, “andrea palladio. atlante delle architetture”, venezia, marsilio editore, 2001. [13] l. puppi, d. battilotti, andrea palladio, milano, electa, electa architettura paperback, 1999. [14] http://www.portaleagentifisici.it/fo_ro_artificiali_ riflettanza_materiali.php?&lg=it (april 2013) figura 7 –sistema multi-layer. screenshot della nuvola in falsi colori di riflettanza, in mappatura termografica e a colori. i due casi mostrano nelle aree evidenziate interessanti risultati di correlazioni fra le grandezze. 82 color culture and science journal vol. 11 (2) doi: 10.23738/ccsj.110209 a case study on light and colour for monuments and cultural assets andrea siniscalco1 1department of design, politecnico di milano, italy. andrea.siniscalco@polimi.it corresponding author: andrea siniscalco (andrea.siniscalco@polimi.it) abstract the enhancement of monumental assets through lighting requires particular attention. the absence of specific laws (except those for the prevention of light pollution and the perishability of certain assets) results in installations whose sole purpose is to make them visible, without offering an effective valorisation at night. in this contribution, it’ll be presented a concept experience for the monumental complex of neptune in bologna (italy), where the choices made were aimed at satisfying specific requests of the client, which also included the use of different shades of white and coloured light. keywords cultural assets, lighting, colour, concept received 14 october 2019; revised 24 november 2019; accepted 29 november 2019 a case study on light and colour for monuments and cultural assets 83 color culture and science journal vol. 11 (2) doi: 10.23738/ccsj.110209 1. introduction the lighting of cultural heritage is an activity of primary importance, especially in a country like italy, one of the states with the highest concentration of world cultural heritage (unesco 2019). it is normal that, despite a not always appropriate conservation policy, the intention of the structures in charge (but also of the population, which every day enjoys these assets) is that of maximising the value of the heritage. the most effective method of making the works of our history usable is undoubtedly that of extending their usability even in the evening and at night with an illumination capable of maximising their value. despite the relatively low costs of implementing lighting systems, cultural assets are made to last, and electrical consumption is a very significant expense item for municipalities. due to the price of functioning and upkeep, often installations are kept switched off, or without proper maintenance. fortunately, technology has been of fundamental help over time. not only to simplify lighting design, but also to drastically reduce consumption, without having to sacrifice the final result. the light sources and the respective control systems guarantee a high flexibility, which however raises some doubts, especially when they’re used on elements of historical-cultural interest. in this paper, i will present a case study focused on the monumental complex located in piazza del nettuno in bologna, which, in occasion of the ongoing renovation of the site, had to be enhanced by paying attention not to distort its nature. 2. the monument and its context the monumental complex protagonist of the case study is the neptune fountain located in bologna (italy). built between 1563 and 1567, it is a brilliant example of cooperation by a team of artisans, artists, architects and engineers (tuttle 2015). the monumental complex is located at the confluence of two important squares in old bologna and is surrounded by impressive historic facades. a squarish basin composes it with a pedestal and a statue that crowns the whole; marbles of two colours and elaborate figures and bronze finishes immediately give the idea of the importance and the magnificence that wanted to be transmitted by this work. pope pio iv (giovanni angelo 'de medici) commissioned the fountain, and the work had the complete supervision of pier donato cesi, a roman governor who summoned the architect tommaso laureti (called “il siciliano”) and the flemish sculptor jean de boulogne (known as “giambologna”). also, the gathering of an impressive international workgroup and a considerable amount of money made it clear right from the start that the aim was to create what was destined to be considered the most beautiful fountain in italy. fig. 1. the neptune monumental complex seen from palazzo d’accursio. courtesy of vistavisuals. although not as popular as other cities of art, bologna registers more than 1.5 million tourists per year (municipality of bologna 2019) and pedestrian transit in this square is considerable even in the evening hours. visitors walk on two main routes around the complex; the path to the right and the one to the left of the fountain. via rizzoli (to the north) and piazza maggiore (to the south) are connected by these pathways. the imposing buildings of palazzo d’accursio and palazzo di re enzo frame the fountain; both are large brick facades enriched by many characterising elements. on the ground, we find pink granite, darker granite slabs and the presence of elements in white marble (figure 1). concerning lighting, currently the only attention given to the monumental complex is provided by a single rotosymmetrical projector for metal halide lamp with opening (estimated by the relative position between the fixture and the statue) that concentrates the entire luminous flux (light emitted by the source) in a cone of 6°. the particularity of this single projector is given not only by the lateral lighting of the statue (which guarantees a proper modelling of the forms) but also by the presence of a sharp shadow (probably will of the designer), the shape of the statue, a case study on light and colour for monuments and cultural assets 84 color culture and science journal vol. 11 (2) doi: 10.23738/ccsj.110209 projected on the building that houses the offices of the municipality of bologna. the remaining lighting on the monumental complex is given entirely by the light that indirectly comes from the reflection of the historical facades and the pavement. as a result, the elements of the fountain are illuminated flatly and uniformly, and the differences between light and dark are exclusively due to the reflection factor of the material and the layer of oxide or deposits that covers most of the elements of the fountain. 2.1. the requests the client requested the laboratorio luce of the politecnico di milano to produce three lighting concepts relating to the monumental complex and the surrounding spaces. in formulating these concepts, a series of requests expressed by the client were taken into consideration, summarized in the following points: • minimise the consumption of electricity; • controlling diffused light; • contain the phenomena of discomfort glare towards passers-by; • enhance the monument of neptune; • provide a clear legibility of the fountain-statue complex for the context, the surrounding buildings in the square, and its components; • use dynamic lighting solutions on special occasions, such as commemorations and anniversaries decided by the municipality of bologna; • lighting the statue differently from the pedestal. initially, three concepts were formulated which, after several discussions with the client (who in turn interfaced with the municipality), were merged into a single preliminary proposal. the produced concept is not only intended to meet regulatory requirements, but also to interpret and enhance the space by mediating with communicative and functional requirements. 2.2. the preliminary analysis before starting to gather ideas on how to enhance the complex with light, the laboratorio luce staff provided a complete lighting survey on the fountain and its surroundings. the survey aimed to evaluate the current state of the lighting system; instrumental measurements, photographic sessions and visual inspections were carried out to characterise the luminous scenario of the statue and the immediate surrounding areas. the reference standards for the measurements were uni 11248:2012 (now replaced by uni 11248:2016) and the european harmonised standard en 13201_02:2004. the measured quantities taken into consideration are illuminance (amount of luminous flux per unit area) and luminance; photometric quantity correlated to the psychophysical sensation of luminance whose value depends on the position of the observer related to the surface itself (fotios, & gibbons 2018). in addition to the lighting survey, a census was also made of the installed lighting fixtures and light sources (which will remain in good part even after a possible renewal intervention) in order to verify the functioning status of the systems but above all, the "quality" of the light present in terms of tonality and ability to reproduce colors. after having carried out a census, it was possible to note that the light sources used are exclusively discharge lamps in traditional gases, of the two types (rea, bullough, & akashi, 2009): • high-pressure sodium lamp hps • metal halide lamp mh the first type of lamp (hps) is very efficient and is often used in urban lighting, where high colour rendering capacity is not required; in fact, this lamp emits a yelloworange light, which offers a limited ability to distinguish colours, but allows the emanation of a considerable luminous flux with a modest electrical power consumption and consequently with reduced energy consumption. sodium lamps are mainly used to light the façades of buildings, i.e. in those parts of the space where yellowgreen colours abound (part of the spectrum where this lamp is well-performing). in this way it is possible to obtain good results even if the colour rendering index of the source is rather low. the colour rendering index (ra) is a number between 0 and 100, used to express how much a light source can render the colours of a predefined set of colour samples (guo & houser 2004); that of the hps lamp is about 20÷23. the metal halide lamp, on the other hand, has a much higher colour rendering (ra=65) but a lower efficiency than the hps. another factor is the colour temperature of the two sources, i.e. a parameter used to describe whether a white light source tends more towards a warm white shade (2000 k, typical of incandescent light sources) or a cool white shade (6500 k, characteristic of natural light with a clear sky). the mh lamps present are at a neutral colour temperature (about 4000 k). these two combined characteristics are plausibly the reason why the mhs were chosen to illuminate the statue and some of the marble elements. a case study on light and colour for monuments and cultural assets 85 color culture and science journal vol. 11 (2) doi: 10.23738/ccsj.110209 3. coloured light for cultural heritage the purpose of the proposal is certainly not to completely replace the luminaires of the area, of all the buildings and the monumental complex. the goal was to enhance the neptune and its pedestal (the castellum), and therefore, the current lighting on the areas not under consideration and will not be modified; however, following the lighting survey, we highlighted all the issues of the site. current technologies related to lighting sources allow us much greater flexibility, without compromising the efficiency of the sources. the leds, if appropriately combined, make it possible to obtain a very varied range of different white tones, also reducing consumption and guaranteeing control flexibility unthinkable with the sources currently installed. this flexibility also allows you to enter a very thorny environment, that of coloured light on cultural heritage. time is not particularly lenient with colour pigments and history, often presents us colourless works of art; and we are used to this, to the point that thinking that once they were coloured leads us almost to feel uncomfortable. many of the great greek works like the parthenon were not at white; the colours were saturated, and often materials like copper, silver and glass paste were used to make the finishes even more vivid. fig. 2. the coloured light projection simulates the appearance of ancient colour on the ara pacis in rome (2008). even the ara pacis in rome was colourful; in 2008 an experiment (figure 2), sponsored by martin professional, a luminaire manufacturer, coloured the bas-reliefs with light, using a gobo (transmissive glass disk, in that case, coloured) for reproducing its ancestral appearance (rossini 2010). the attempt was rather coarse and not precise; however, it had the great merit of creating a particular resonance and of being a precursor to more recent reconstructions (with advanced technologies, such as augmented reality) that are still discussed today. piazza del nettuno was surely not as colourful as the ara pacis was; however, the use of colour on cultural heritage has been used from time to time. just think of the coloured lighting of the castello sforzesco in milan (figure 3) by duilio passariello, which caused many criticism (like the one of the italian writer umberto eco) and then abandoned in favour of a more reassuring warm white light. the radical modification of the colour of the lighting is a much-discussed topic, especially today that the more efficient solid-state systems are supplanting the old systems with discharge lamps. even the only change in the colour temperature, perhaps accompanied by better colour rendering index, is enough to trigger fierce criticism from the inhabitants and field experts (like the recent cases of rome and modica in sicily). fortunately, however, the new control systems allow us to design a light that is still over time, allowing the possibility to use colour (even just change the shades of white) for certain occasions and for a specific time; to produce the so-called “wow-effect”, but to bring the situation back to normal, avoiding to definitively misrepresent the space. fig. 3. lights at castello sforzesco in milan (italy). the installation received the critics (colonnetti 2001) by many cultural figures such as umberto eco (writer), arnaldo pomodoro (sculptor), emilio tadini (painter and writer) and carlo bertelli (art historian). 4. the proposals already identified in the survey phase, the two privileged directions of observation coincide with the routes that tourists and users of the square usually follow: the first a case study on light and colour for monuments and cultural assets 86 color culture and science journal vol. 11 (2) doi: 10.23738/ccsj.110209 route is the one that goes from piazza maggiore to via rizzoli, while the second is the one that goes from via rizzoli to piazza maggiore. the identification of these routes is essential both for the design of significant and visible lighting effects for most users, and for the evaluation of the parameters of quality of the system, such as containment of glare for the main directions of view of the observers. 4.1. the lighting of the statue and the pedestal it was not possible to provide lighting from below (with submerged luminaires) due to the structural problems of the basin. therefore, the first concepts presented all had an illumination from above (from the walls of the buildings), preserving the concept of projection of the shadow already existing. the connotation of the square given by this effect is such that it was thought to reinforce the concept, using three-point lighting and producing three sharp shadows (instead of one) on the surrounding walls. however, the municipality had the desire to remove the shadow to contain the glare and therefore, in the final concept, we agreed not to cast any shadows on the walls. the lighting with three projectors (positioned on brackets mounted on the palazzo d'accursio and the palazzo del podestà) has nevertheless remained, to increase the luminance of the statue, but providing a system of custom barn doors to contain glare for those who look at the statue against the light. fig. 4. digital photo-elaboration of a daytime picture of the complex to simulate the lighting in one of the early concepts (shadows were later eliminated). four warm-light projectors (wide flood 50°, 24w / 3400lm cob led with colour temperature of 3000 k) have also been proposed, which will be aimed at the pedestal (the castellum); three of these projectors are mounted on the same structures that support the projectors of the statue, while the fourth will be positioned on the wall of the entrance courtyard of palazzo di re enzo. the three projectors used to light the statue will have a cooler colour temperature (narrow spot 10°, 35w / 5000lm cob led with colour temperature of 5000 k), which will ensure greater prominence to the bronze structure. in this way, the contrast with the castellum (in marble) will be even more marked. cold light for the god of the sea and warm light for the earth on which he stands. in addition to the regular white light, three rgb projectors (red, green and blue, 27.45w / 963lm) will be installed in the same position as the white light projectors that make up the neptune's accent light, to provide temporary coloured lighting for events such as events: • blue lighting for world diabetes day in midnovember. • blue lighting for the world autism awareness day at the beginning of april. • pink lighting for komen italia breast cancer day at the end of september. • red lighting for world blood donor day in midjune. • purple lighting for world epilepsy day at the beginning of february. for the coloured light fixtures as well, we planned the installation of adjustable shielding systems for better control and definition of the beam related to the silhouette of the statue. fig. 5. 3d simulation of the rgb lighting of the complex. digital reconstruction of the area was necessary to present the idea to the municipality. since some of the scenarios obtained with the coloured lights will lead the statue to have very low luminance levels compared to lighting with white light, it was decided that to make more visible the neptune compared to the context, when using rgb projectors, the fixtures that illuminate the castellum will be kept off, as visible in figure 5. a case study on light and colour for monuments and cultural assets 87 color culture and science journal vol. 11 (2) doi: 10.23738/ccsj.110209 fig. 6. 3d simulation of the illuminance levels looking at the complex in the direction of via rizzoli. fig. 7. 3d simulation of the predicted luminance levels looking at the complex in the direction of via rizzoli. the luminance levels of the actually installed luminaires average around 5 cd/m2. fig. 8. 3d simulation of the illuminance levels looking at the complex in the direction of piazza maggiore. fig. 9. 3d simulation of the predicted luminance levels looking at the complex in the direction of piazza maggiore. the luminance levels of the actually installed luminaires average around 5 cd/m2. 4.2. additional lighting of the spaces surrounding the fountain in addition to restoring the functionality of the current lighting systems of buildings (projectors on the façades, light points on the windows, etc.) was also developed a proposal for the lighting of the spaces surrounding the fountain which consisted of a series of light signs placed on the floor in correspondence with the lines of white stone inserted in the flooring. these devices will emit a very controlled luminous flux (narrow blades of light 4,7w / 360lm), a sign of light to channel the attention of passersby. the colour temperature chosen is neutral (4000 k). some of the initial concepts provided for a large number of these light elements (and an rgb version of them) but, although these would guarantee great flexibility of use, in the end, we opted for a system of light lines that created a sort of corridor that ideally directs pedestrians towards neptune. the aim is to create a dynamic perceptual context aimed at placing the complex at the centre of the hierarchies of visual perception of the area. in addition to the luminous signs on the walking surface, the windows of palazzo d'accursio (in correspondence with the salaborsa library) and the battlements of palazzo di re enzo will also be lit. these additional lighting fixtures (narrow beam at 5.7w / 720lm, to illuminate only the profiles of the elements) will also, have a colour temperature of 4000 k. a case study on light and colour for monuments and cultural assets 88 color culture and science journal vol. 11 (2) doi: 10.23738/ccsj.110209 fig. 10. 3d simulation of the lighting of the complex. it is possible to observe the light hypothesised for the battlements. 4.3. lighting management system the luminaires for the statue and the adjacent areas were all based on led technology; this allowed us to have maximum control over them. for the entire system, we hypothesised the installation of a management system capable of ensuring the achievement of the following objectives: • possibility of creating predefined lighting scenes that can be selected by the operator for events/recurrence; • dimming and partial shutdown of the system in the late hours of the night to contain operating costs; • possibility to create new light scenes in case of special needs, through the composition and regulation of the lighting of the individual elements of the fountain, statue or square. for this application, the choice of the protocol for the management system leads to some possible options: dali, dmx or a hybrid solution. a control system with a simplified interface (to make the programming of the scenes accessible) would guarantee additional and innovative functions for dynamic lighting, which would allow the municipality to assign new and changing perceptual values to the context, depending on particular situations (di salvo 2014). 5. conclusions the main purpose of the work carried out was to provide the municipality of bologna with ideas for enhancing the monumental complex, with contained costs and a low energy consumption. the designed sources have a much longer duration than those currently installed and, being easily controllable digitally, they allow programming of on and off cycles optimised with the time of day, the period of the year, and many other factors. with the new control systems and a specifically customised user interface, it is possible to offer the municipality a tool to make the monumental complex of neptune, a veritable scenographic element, easily controllable and scalable for festivals and events that can take place on-site; all without sacrificing classic white lighting, designed to enhance colors, shapes and materials, limiting glare towards passers-by and guarantee a good usability of the cultural site. 6. conflict of interest declaration the author declares that nothing has affected his objectivity or independence in the production of this work. neither the author nor his immediate family member has any financial interest in the people, topics or companies involved by this article. neither the author nor his immediate family member had a professional relationship with the people and companies cited in this article. neither the author nor his immediate family member is involved in a legal dispute with the people and the companies cited in this article. no conflict of interest including financial, personal or other relationship with other people and organization within three years of beginning the submitted work that could inappropriately influence, or be perceived to influence, this work. 7. funding source declaration this research did not receive any specific grant from funding agencies in the public, commercial, or not-forprofit sectors. 8. short biography of the author andrea siniscalco msc in industrial design in 2002. phd in design and methods of product development in 2007. vice-director and teacher in the master in lighting design & led technology of politecnico di milano. teacher of lighting theory at the school of design. vice president of gdc associazione italiana colore. fields of interest are lighting design, visual perception and colour. references colonetti, a. (2001) ‘i limiti della città serve uno spazio per dare più visibilità al sistema design.’, corriere design, 3, p. 1. a case study on light and colour for monuments and cultural assets 89 color culture and science journal vol. 11 (2) doi: 10.23738/ccsj.110209 comune di bologna (2019) turismo a bologna, ecco com'è stato il 2018. available at: http://www.comune.bologna.it/news/turismo-bologna-eccocom-stato-il-2018 (accessed: 11 october 2019). di salvo, s. (2014) ‘innovation in lighting for enhancing the appreciation and preservation of archaeological heritage’, journal of cultural heritage, 15(2), pp. 209–212. doi: 10.1016/j.culher.2013.03.001. en 13201_02:2004 “road lighting part 2: performance requirements”. fotios, s. and gibbons, r. (2018) ‘road lighting research for drivers and pedestrians: the basis of luminance and illuminance recommendations’, lighting research & technology, 50(1), pp. 154–186. doi: 10.1177/1477153517739055. rea, m., bullough, j. and akashi, y. (2009) ‘several views of metal halide and high-pressure sodium lighting for outdoor applications’, lighting research & technology, 41(4), pp. 297–320. doi: 10.1177/1477153509102342. richard j. tuttle (2015) the neptune fountain in bologna bronze, marble, and water in the making of a papal city. turnhout, belgium: harvey miller. rossini o. (2010). i colori dell’ara pacis. storia di un esperimento. archeomatica, 1(3), 20-25. unesco (2019) world heritage center. available at: https://whc.unesco.org (accessed: 11 october 2019). uni 11248:2012 “illuminazione stradale selezione delle categorie illuminotecniche”. cultura e scienza del colore color culture and science 8 cultura e scienza del colore color culture and science | 04/15 1veronica valdegamberi veronica.valde@gmail.com 2giulia paggetti giuliapaggetti@gmail.com 2gloria menegaz gloria.menegaz@univr.it 1department of linguistics, university of verona, italy 2department of computer science, university of verona, italy on the perceptual/linguistic origin of the twelfth basic color term in the italian color lexicon 1. introduction the seminal work of berlin and kay introduced the concept of universal basic color terms (bcts) [1], namely red, green, blue, yellow, orange, purple, pink, brown, gray, white, and black. according to their definition, color terms are operationally defined as basic only if monolexemic and psychologically salient for all speakers, but not if restricted in application to narrow classes of objects, or included in the signification of other basic color terms. they proposed that these color words act as focal points for all the basic color categories in all the languages with a developed color vocabulary. in the last decade, the restriction to eleven universal basic colors has been put into question. some researchers provided evidence on the existence of an additional basic term in the category of blue for the greek, turkish, russian and, more recently, maltese languages [2-6]. in the same line, our work [7-15] has emphasized the need for the italian speakers to assign the term corresponding to light blue, azzurro, to a separate category. in particular, in the constrained color naming experiment described in [7] participants were instructed to name samples of colors using only the eleven basic terms identified by berlin and kay. after performing the experiment many participants reported the uneasiness on using the term blu (blue) to label colors in the lighter blue portion of the spectrum. in addition, the lightness of the centroid for the blu category was well above the lightness of the category focal. in order to disambiguate the role of linguistic and perceptual mechanisms in color categorization and to shed light on the existence of the twelfth category in italian, other experiments were performed and the outcomes of these confirmed our conjecture. here we report on both an unconstrained color listing experiment and a stroop test with (in)congruent word/ink parings [8, 16]. we refer to [7-15,19,20] for additional information. this paper is organized as follows. section 2 describes experiment 1 (color listing) and briefly summarizes the outcomes of experiment 2 (stroop test). section 3 illustrates the results and section 4 presents the conclusions. 2. methods 2.1 experiment 1: color listing the color listing experiment was designed to determine whether there is a measurable difference in the spontaneous recall frequency of names associated with basic colors with respect to other color categories. in this way, the recall frequency can be considered as a further indication of the semantic difference between basic and non-basic colors and thus of the “basicness” of a given color name. accordingly, the recall frequency for the term azzurro was assessed by a color listing experiment. abstract color categorization involves a cognitive mechanism that assigns linguistic labels to perceived colors. in their pioneering study of 1969, berlin and kay proposed the existence of eleven universal basic colors, founding the “universalist” theory on color naming. since then different studies have been proposed either supporting or refusing such a conjecture based on new evidence. one of the most fascinating elements of this research is the debate on the nature of the color naming mechanism: is it a predominantly perceptual or linguistic effect? an inherent aspect stemming from berlin and kay’s conjecture is the “weak relativist hypothesis” concerning the emergence of additional basic color categories besides the established 11, specific to a certain language. in this paper we investigate these two issues and propose some arguments in favor of the existence of a twelfth basic color term in italian. following the indications of the results of our previous work, two experiments were performed, focusing on the linguistic and the perceptual aspects, respectively. results support the hypothesis of the existence of an additional basic category named azzurro (light blue), as it is the case for turkish, greek, russian and maltese. 904/15 | cultura e scienza del colore color culture and science a questionnaire was prepared and submitted to the informants participating in the experiment. it consisted of two parts. in the first, demographic data were requested in order to enable the identification of other possible factors influencing the recall rate (e.g. gender, age). the second part was devoted to the color listing task. the requested personal data were: gender, age, education, job, hometown and knowledge of foreign languages or italian dialects. the participants were also asked whether they had particular involvement in color management in their everyday life (either for their professional activity or in their spare time). thirty-nine people aged between 15 and 62 volunteered for the experiment. all of them were native italian speakers. the task consisted of listing all the known color names freelyand without constrains on the type and number of names provided. there was no time limit and response time was not recorded. 2.2 experiment 2: stroop test the stroop test brought a new argument in favor of the weak relativity hypothesis providing additional evidence of the existence of at least a twelfth color category in the italian language. the stroop test was introduced in 1953 by john ridley stroop [16] and is based on the assessment of the reaction time in a color naming task. basically, color name and color ink pairs are shown in either congruent (color name corresponds to ink color) or incongruent (color name and ink color are different) parings. stroop demonstrated that in the second case (e.g. red ink and green word) the naming of the ink color takes longer and is more prone to errors than in the first (green ink and green word). the aim of the experiment was to assess whether naming the azzurro (light blue) ink color would take longer than naming the blu (dark blue) ink color if both were paired to blu color word. five experiments were performed for assessing the reaction times in different congruent/incongruent conditions using different combinations of color names and ink color parings in order to avoid the interference from other factors possibly biasing the results of the experiment. in particular, the linguistic nature of the mechanism was investigated by separately performing the experiment on the verde (green) and the blu (blue) categories, respectively. in the first, regarding the blu category, six ink colors were used: dark blue, light blue, red, yellow, purple and pink. the six colors were paired with four colors names rosso, (red), blu (blue), viola (purple) and giallo, (yellow), resulting in 24 possible combinations (e.g. red ink – rosso word, red ink – blu word etc.). in the second experiment, regarding the green category, the two blue ink colors were replaced by two green colors that were equidistant in lightness and the word blu was replaced by the word verde, while keeping all the other conditions unchanged. the choice of green was motivated by the fact that the perceived colors corresponding to the green category cover a large portion of the spectrum including both high and low lightness values, as it is the case for the english blue. the underlying hypothesis was that statistically significant mean reaction time difference for low and high lightness ink colors when paired to the congruent color word (blu and azzurro, respectively, for the blue category and verde for the green category) would have provided evidence in favor of the predominance of a linguistic rather than a perceptual mechanism. alternative: the underlying hypothesis was that low and high lightness ink colors, when paired with incongruent color words (blu and azzurro, respectively, for the blue category and verde for the green category) would provide statistically slower mean reaction times than those for the congruent pairs, thus supporting a linguistic rather than perceptual mechanism. in other words, our claim was that if the reaction time was the consequence of a predominantly perceptual effect, the same trend would have been observed for the two categories. conversely, a different trend would have supported the linguistic hypothesis, since in this case the blu and verde categories would have revealed a different underlying linguistic mechanism affecting reaction time. the third, fourth and fifth experiments were aimed at avoiding the influence of other confounding factors. the munsell coordinates and the lightness of the colors used were as follows: red 7.5r 5/20, l*=51.85, dark blue 5pb 1/10, l*=12.63, light blue 5pb 6/14, l*=60.91, yellow 5y 9/12, l*=89.28, purple 2.5p 3/18, l*=30.64, pink 7.5rp 7/10, l*=44.61, dark green 10gy 1/10, l*=13.14, light green 10gy 6/14, l*=61.38. we refer to [8] for more details. 3. results 3.1 experiment 1: color listing results confirmed the psychological salience of the 11 basic color terms. as shown in table 1, the basic terms occupy the first positions and reach very high response frequencies. the bianco (white) category was named by all 39 participants, while the basic term recalled with the lowest frequency (33 participants) was viola (purple). interestingly, the word chosen to designate light-blue was azzurro, which at that time was not considered to be a basic term, reaching frequencies similar to those of other basic terms (35 participants). this supports the hypothesis that italian speakers do need a term 10 cultura e scienza del colore color culture and science | 04/15 denoting that particular area of the color space and azzurro seemed to be the best candidate. beyond azzurro, other terms denoting approximately the same region reached good frequencies, for instance celeste and turchese. after viola there was a sharp variation in the naming frequencies. the total number of provided names was 136. the 12 colors ordered according to decreasing frequency of recall were white bianco (white), rosso (red), giallo (yellow), nero (black), verde (green), marrone (brown), blu (blue), rosa (pink), arancione or arancio (orange), azzurro (light blue), grigio (grey) and viola (purple). the light blue color comes in this list before two basic colors, gray and purple, which highlights its psychological saliency in the italian language. interestingly, for other very wide regions of the color space, like that for green, just one basic term seems to be sufficient. in this experiment almost every subject (90%) proposed an alternative name for the blue region (beside blue). interestingly, this was not the case for green (48% only). moreover, the additional terms proposed for blue were mainly simple terms with high consensus, while the terms for green were compound terms denoting objects and reaching very low frequencies (about 30 such names were provided). as can be seen in the table 1, agreement on an additional term denoting the green region was not reached, in contrast to the case of the blues. there are no simple names widely implemented and known, like azzurro, that might be used in order to enlarge the lexicon referring to the green table 1 frequency recall of colors color name num. color name num. color name num. bianco 39 giallo canarino 3 bianco sporco 1 rosso 37 vermiglio 3 corallo 1 giallo 37 rosa cipria 2 rosa antico 1 nero 37 verde oliva 2 rosso sangue 1 verde 36 (rosso) mattone 2 bianco perla 1 marrone 35 grigio perla 2 rame 1 blu 35 ecru 2 verdemare 1 rosa 35 senape 2 grigioverde 1 arancio/arancione 35 blu di prussia 2 topazio 1 azzurro 35 rosso scarlatto 2 giada 1 grigio 34 bruno 2 carta da zucchero 1 viola 33 rosa carne 2 terra 1 lilla 17 prugna 2 lavanda 1 (giallo) oro 17 acqua marina 2 violetto 1 (grigio) argento 16 ghiaccio 2 grigio fumo 1 beige 15 cobalto 2 blu aviazione 1 fucsia 15 sabbia 2 rosa pallido 1 (giallo) ocra 14 (verde) cromo 2 verde muschio 1 celeste 13 giallo paglierino 2 verde vescica 1 turchese 12 verde mela 2 verde montano 1 indaco 12 grigio topo 2 inox 1 bordeaux / bordo’ 12 crema 2 ottone 1 (rosso) magenta 10 verde militare 2 nero grafite 1 (rosso) porpora 10 verde prato 2 nero di seppia 1 blu oltreoceano-mare/oceano 8 verde marcio 2 bianco di zinco 1 terra di siena (bruciata) 8 giallo arancio 1 blu ginepro 1 verde smeraldo 7 aragosta 1 rosso bandiera 1 (bianco) panna 7 rosso vivo 1 rosso rubino 1 verde acqua 6 rosso pompadour 1 giallo di napoli 1 (rosa) salmone 6 bruno giallo 1 verde bandiera 1 giallo limone 6 blu di sevres 1 verde vagone 1 amaranto 6 blu cina 1 blu navy 1 ciano 5 pervinca 1 khaki 1 ciclamino 5 verde foglia 1 testa di moro 1 avorio 5 verde cinese 1 grigio polvere 1 (grigio) antracite 5 verde imperiale 1 castano 1 rosso carminio 5 verde nero 1 verde bosco 1 bronzo 5 verde giallo 1 granata 1 (verde) petrolio 4 verde ftalo 1 castagno 1 pesca 4 porpora rosa 1 pero 1 verde pisello 4 ocra rossa 1 ciliegio 1 blu notte 4 verde reale 1 caramello 1 vinaccia 3 verde mirto 1 menta 1 cremisi 3 azzurro marino 1 giallo vivo 1 nocciola 3 verde fluorescente 1 verde acido 3 verde pino 1 region. this is probably why the few participants who used lightness modifiers (chiaro and scuro light and dark) applied them to the verde term. a discussion on the existence of a twelfth color class was initiated by boynton and olson (b&o) in [17] and reconsidered by sturges 1104/15 | cultura e scienza del colore color culture and science non-basic color terms: the results of the three studies agree in this respect and highlight similar findings despite the different paradigms and languages. an interesting point is that nonbasic terms with the highest recall frequencies are the same as those in the other two studies. they seem to refer to the regions where basic color terms are rarely used, namely those between white and brown/yellow (“cream, mustard, beige” for s&w, oro, beige, ocra in our experiment) and between white and purple/red (“lilac, violet, burgundy” for s&w, lilla, fucsia in our experiment). overall, our results provide a clear indication towards the linguistic point of view, since the name azzurro features a higher recall frequency than many other basic terms, while confirming the saliency of the eleven basic color terms. impact of other factors gender several studies have shown that women tend to produce and use more color names than men. we tried to investigate the existence of a correlation between the participants’ gender and the number of terms provided. our participants were 11 males and 28 females. the average number of terms named by males was 22.63, against 20.42 for females. in order to better investigate the issue, the standard deviation of the parameter was measured, resulting in 9.11 for males and 9.47 for females. the distribution of the values in the two groups is quite similar. the results of our experiment show analogous numbers of terms provided regardless of gender. however, a gender-balanced sample would have been required for robust conclusions. statistical significance? age participants were aged between 15 and 62. a correlation between age of participants and number of terms provided was observed. the participants were organized into three age groups (<30; 30-45; >45). while the first and the last ones provided approximately the same number of color names, the other one (30-45) provided a significantly lower number of terms. you have to include the p value. color experience participants were also divided into two groups according to their involvement in color matters. one group included people who have had someinvolvement in color (regardless of the involvement in nature), while the second group included people who have not. participants who reported an involvement provided a significantly higher number of color names. results are summarized in table 2. finally, the recall frequency for non-monolexemic names using lightness modifiers is given in table 3, where chiaro stands for light, scuro for dark, and vivo for vivid. overall, the experiment confirmed the special status of the 11 basic color terms, but also and whitfield (s&w) in [18]. although our experimental procedure and method were different, their main findings were confirmed as detailed in the following sections. interestingly, the same conclusion was supported by experimental evidence obtained in a purely linguistic framework. comparison with b&o and s&w basic color terms: the psychological saliency of the eleven basic color terms was confirmed by the experiment. recall frequencies drop from 84.6% (last basic term) to 43.5% (first nonbasic term). the most important difference with respect to s&w was that in our experiment a twelfth potential basic color term had appeared (azzurro). this is most probably due to the cultural difference (italian versus english). in [17,18] the authors foresaw the existence of a twelfth basic color for the english language based on the finding that “cream” (b&o) and “peach”. (s&w) obtained low response times and a fairly high consensus with respect to the other non-basic color terms. these two hypotheses were weakened by two factors: (i) strong evidence in the data was missing (response time and consensus), and (ii) the data led to a different indication for the missing name, which is supposed to be unique. on the contrary, the current experiment has provided a clear indication from the linguistic point of view, since the name azzurro has a higher recall frequency than other basic terms. on top of this, such a term, corresponding to the light blue region, is in line with recent findings regarding other languages like greek, turkish, russian and maltese [2-6]. it is noteworthy that berlin and kay proposed a hierarchy in color names that could in principle enclose such a term without losing generality. the different paradigm used in our experiment highlights another important difference concerning achromatic colors. b&o did not report on achromatic colors because of their poor representation in the osa-ucs space. for s&w achromatic colors appeared in the last positions (in terms of consensus and response time) if compared to the other basic color terms. in our experiment, bianco (white) and nero (black) lie at the top of the basic color terms (in terms of frequency of recall), in agreement with the hierarchy proposed in by berlin [1], while this was not the case for b&o and s&w. even more interestingly, the six hering primaries (red, green, blue, yellow, white, black) appear shortly after, followed by the other basic color terms (gray appears in the last position). we consider this as a strong indication that our results have a solid psychological correlate that might include perception and that seems to be stronger than for the other considered studies. 12 cultura e scienza del colore color culture and science | 04/15 provided evidence of the need of a twelfth color name, in the italian language, at least: azzurro. 3.2. experiment 2: stroop test results support the hypothesis that two blue basic color terms do exist. the dark and light blue colors used in the experiment, having the same hue but different lightness, appear to belong to two different color categories. a student’s t-test (p<0.05) showed that for every possible pairing (color ink and color word) the blu color word had significantly shorter reaction times when paired with dark blue ink than in all other conditions (fig. 1, left plot). this means that the participants name more quickly the dark blue rather than the light blue ink color if both are paired with the blu color word. in the control experiment, the t-test for each possible combination of stimuli (ink color and color word) showed that the color word verde has significantly shorter reaction time when paired either to light or dark green colors than in any other condition (fig. 1, right plot). 4. conclusions our studies brought evidence in favor of the hypothesis of the existence of a twelfth basic color class in the italian language in the light blue (perceived) color range named azzurro, as well as in its linguistic reference to perceived colors. both the color listing and the stroop tests supported such a conjecture. no other factors (age, gender, color experience) resulted in having a significant impact on the outcomes of the two experiments. however, this issue deserves further investigation. bibliography [1] berlin, b., kay, p.: basic color terms: their universality and evolution. berkeley, ca: university of california press (1969). [2] androulaki, a., gômez-pestaña, n., mitsakis, c., jover, j., coventry, k., davies, i.: basic colour terms in modern greek: twelve terms including two blues. journal of greek linguistics 7(1), 3–47 (2006). [3] özgen, e., davies, i.: turkish color terms: tests of berlin and kay’s theory of color universals and linguistic relativity. linguistics 36(5), 919–956 (1998). [4] paramei, g.: singing the russian blues: an argument for culturally basic color terms. cross-cultural research 39(1), 10 (2005). [5] winawer, j., witthoft, n., frank, m., wu, l., wade, a., boroditsky, l.: russian blues reveal the effect of language on color discrimination. pnas 104(19), 7780–7785, (2007). [6] borg a. towards a diachrony of maltese basic colour terms. new directions in colour studies. biggam cp, hough ca, kay cj, simmons dr, editors. amsterdam/ philadelphia: john benjamins; (2011). [7] paggetti g., bartoli g., menegaz g., re-locating colors in the osa space, attention, perception and psychophysics, vol. 73, n. 2, pp. 491-503 (2011). gender age color experience m f <30 30-45 >45 si no µ 22.63 20.42 21.23 17.07 25.33 26.63 15.75 σ 9.11 9.47 8.4 6.7 12.22 10.22 3.68 lightness modifiers verde chiaro verde scuro marrone chiaro marrone scuro grigio chiaro bruno scuro blu chiaro blu scuro giallo chiaro giallo scuro rosso vivo giallo vivo 5 2 2 2 1 1 1 1 1 1 1 5 table 2 mean and standard deviation of frequencies over gender, age and color experience. table 3 number of recalls of compound names using a lightness modifier. chiaro stands for light, scuro for dark, vivo for vivid.     figure 1 average reaction time for the blu (on the left) and verde (on the right) term. 1304/15 | cultura e scienza del colore color culture and science [8] paggetti, g. human perceptual factors in imaging: a link between cognitive and computer sciences, doctoral dissertation, doctoral course in computer science, university of verona (2011). [9] paggetti, g., menegaz, g.: is light blue (azzurro) color name universal in the italian language? color and reflectance in imaging and computer vision workshop, international conference on computer vision. crete (sept 2010). [10] paggetti g., menegaz g., exact location of consensus and consistency colors in the osa-ucs for the italian language, color research and application, vol. 8, n. 6, pp. 437-447 (2013). [11] paramei, g. menegaz, g. ‘italian blues’: a challenge to the universal inventory of basic colour terms, colore e colorimetria, santarcangelo di romagna (rn), maggioli editore, proceedings of “ix conferenza del colore”, firenze, sept. 19-20, pp. 164-167 (2013). [12] paggetti g.; menegaz g., locating colors in the munsell space: an unconstrained color naming experiment, perception, proceedings of the european conference on visual perception (ecvp), alghero, italy, sept. 1-6 (2012). [13] paramei, g. menegaz, g., italian blues: a challenge to the universal inventory of basic colour terms, journal of the internatioal color association , vol. 13 pp. 27-35 (2014). [14] g. paggetti, g. menegaz, g. paramei, color naming in italian language, color research and application, pp. 1-14, doi:10.1002/col.21953, (2015). [15] valdegamberi, v., paggetti, g., menegaz, g. on the perceptual/linguistic origin of the twelfth basic color term in the italian color lexicon, colour and colorimetry multidisciplinary contributions eds. maurizio rossi, maggioli, proceedings of vii conferenza nazionale del colore, roma, pp. 291-298, sept. 15-16 (2011). [16] stroop, j.: studies of interference in serial verbal reactions. journal of experimental psychology 18(6), 643–662 (1935) [17] boynton, r., olson, c.: locating basic colors in the osa space. color research and applications pp. 224–235 (1987) [18] sturges, j., whitfield, t.: salient features of munsell colour space as a function of monolexemic naming and response latencies. vision res. 37(3), 307–313 (1997) [19] sandford, j. l. blu, azzurro, celeste what color is blue for italian speakers compared to english speakers?,proceedings of the eighth national color conference. gruppo del colore, alma mater studiorum università di bologna, facoltà di ingegneria, bologna, italy, 13-14 settembre 2012. colour and colorimetry. multidisciplinary contributions. vol. viii b, (ed.) maurizio rossi – dip. indaco – politecnico di milano, santarcangelo di romagna: maggioli editore. pp. 281–288 (2012) [20] menegaz g.; paggetti g., is the azul class unique in the spanish language?, perception, vol. 40, ecvp abstract supplement, 2011, pp. 80-80 cultura e scienza del colore color culture and science 36 cultura e scienza del colore color culture and science | 04/15 presence felt more often than not. the crossshaped architectural plans of cathedrals were oriented with the altar area space facing toward the east; this placement allowed for light to shine through the stained glass windows and illuminate the holy altar area to magnify the divine effect. this tradition of strategic lighting carries on in modernist architecture, albeit with varied mid-century twists. so much so that long before a visitor enters the case-study church of the epiphany, the light scoops territorialize the exterior with their powerful presence. walking up second avenue from the south, the church of the epiphany’s spiky tower slices into the airspace above, flanked on the lower left by a large, thick tower blunted on angle at the top. (see figures 2 and 3.) another robust angled mass sits to the right of viewer entry (although the visual presence of this tower is more noticeable from the western approach, due to current landscaping conditions). the visitor discovers, once inside, that the two squat towers are the light wells for the holy niches edging the entry and sanctuary spaces: the baptismal font and side prayer chapel. the strong massing presence of the light scoops on the exterior spells out the importance of light as a design feature. the church of the epiphany’s light scoops emit low drama and even in spring afternoon light anticlimactic, rather prosaic, and ineffectual actual light. yet, the presence of skylights (which means a visual absence of ceiling) above the baptismal font, side prayer niche, and front altar still offers a perceived closer (and less impeded) connection to the divine forces above. (see figure 4.) the disappointing interior luminance from the light scoops may have been an intentional design choice to convey a religious message of darkness and sin. or, more likely, the light quality may be partially due to grimy and barred skylights in need of cleaning or poor placement of the skylights themselves. the light quality also suffers from the church site hemmed in by the tall new york city skyline on surrounding blocks – as is typical in this crowded cityscape. (see figure 5.) the sun just can’t angle in as directly here as at kresge chapel where the site is much more open – even allowing light to bounce in from ground level, as will be discussed below. [the above 1. introduction this paper offers a case-study comparison of the atmospheric effect of the manipulation of color and light in two modernist religious spaces: the church of the epiphany by belfatto and pavarini in new york city, new york (1965-1967) and kresge chapel by eero saarinen in cambridge, massachusetts (1953-1955). the chosen religious compounds are located in similar climates and with geographic coordinates in close proximity; as a result, the sites have similar locations for sun angles in summer and winter. they house the worship of differing religious practices and are located in urban areas (in contrast to previously researched midwestern case-studies). as the religious building is a genre typically designed to invoke heightened spiritual experiences, the paper examines how the design choices of each architectural team affect the color experience inside. this proposed paper specifically exposes major massing decisions (placement of mass and volume of buildings), material choice, sculpting of light, proximity of color zones, and location of colors in relation to visitor experience. [author’s note: the paper probes further into a topic i began to address in a case-study paper on religious structures in the midwestern united states presented at the international color association aic 2011 interaction of colour and light midterm meeting of the international color association in zurich, switzerland on 07-10 june 2011. the buildings analyzed were annunciation priory by marcel breuer in bismarck, north dakota (1959-1963); christ church lutheran by eliel saarinen and associates in minneapolis, minnesota (1949); and mount zion temple by erich mendelsohn in st. paul, minnesota (19501954).] (see figure 1 for light parti diagrams of the five spaces mentioned above.) 2. church of the epiphany in a religious context, light and golden color abound think the egyptian sun god, ra, or the shining flat halos of cimabue or gold leaf sheets caked on auspicious statues by the devout people of thailand, to only name a few [1]. more specifically in religious architecture, controlled and golden light makes its divinely meaningful 1jada schumacher jada_schumacher@fitnyc.edu 1 communication design department, fashion institute of technology color, mon dieu: a case-study comparison between the church of the epiphany (new york city) and kresge chapel (cambridge, massachusetts) 3704/15 | cultura e scienza del colore color culture and science interpretation may, in fact, be too charitable. it could also be argued that the space ineffectively makes use of the promise of light shown in the exterior massing and that the building, as a whole, fails to move visitors in a way that could be defined as positive enough to encourage a return visit except out of religious obligation.] belfatto and pavarini’s church provides almost no sense of intimacy, even in the offset niches that end up feeling more like vacuous caverns or over-scaled chemistry test tubes. in this context, the word “masses” offers an interesting double meaning: the name of the scheduled religious services and also the idea of throngs of people that function more as numbers than as shining individuals. [in fact, the church offers an emotive feeling similar to fascist architectural masterpieces such as the milano centrale train station. as a traveller emerges from long escalator tube at the bustling italian thoroughfare, the transit tunnel frames a first exterior view: a grand horse statue foaming at the mouth. navigating the tight underground passage only to be emotionally trampled upon by a fiery horse, the visitor ingests a palpable message of powerlessness. once past the huge, seemingly threatening equine and inside the station, the vibe of vulnerability continues for the visitor waiting for a train to arrive. the fascist iconography and strong frieze imagery, the large shell of space at an inhuman scale, and the whirring noise of people and trains reverberating in the circulation hall encourage the tangible perception of the individual self as one meek, weak entity in a vast system.] the light inside the church of the epiphany, during mass on a spring saturday afternoon, showcases – in the midst of this empty inhumane space – spasmodic glimmers of glory and a glimpse of hope with shining saturated greenish yellow rays hitting parishioners during the service. (see figures 6 and 7.) here, select figure 1 – diagrams of the sculpting of light in the five spaces. clockwise from top left kresge chapel facing the altar, sectional view of mount zion temple, sectional view of original chapel at annunciation monastery, church of the epiphany facing the altar, and christ church lutheran facing the altari. 38 cultura e scienza del colore color culture and science | 04/15 groups of parishioners are momentarily lit with the sun’s angled light, sparking a slightly upbeat note in the sanctuary space. this color moment seems to convey that the presence and prayer of individuals matters for a bit. the parishioners embalmed in the glow seem momentarily not nameless, special and bright even, in the midst of this large, dark building envelope. yet, the chromatic light loses some momentum as it bounces off of neutral, unmemorable floor materials and on the procession of drab brickwork wrapping around the sanctuary. the cool and warm grey pavers in the walkways soak away some of the light color, as the waxy, nearly matte finish dulls this light from the window. (see figures 8 and 9.) note here that the yellow rays have a greenish cast. the resultant sour yellow provides just a tinge of the upbeat positivity of yellow hues. but, mixed with a dour, almost sickly green, the yellow is depleted by a wash depicting a color of physical weakness (as in nauseous or ill). just as the repeated rituals of repentance, expected obedience, and required presence at mass of the catholic faith provoke human guilt, so too can the yellow-going-green hue convey ideas of a flawed people, at the whim of god, clearly here to meticulously serve god’s will in hopes of a personal redemption. the color and light zones – spaced far apart and composed of matched up jagged shapes of glass in belfatto and pavarini’s compound feel sparse and inadequate although they take up a significant amount of wall square footage. the windows, lighting the main space, are supplemented by the rigid grid of crossshaped pendant lighting hung from above. even the mundanely wide circulation routes leave the visitor lacking fulfillment. alas, the sense of order, controlled shaping, and scale convey an inapproachable, all-powerful message of god. gratification does not seem to be lastingly calculated into the design of this dark and hollow spatial experience. as such, the light and scale design choices in this vastly impersonal church space can be interpreted as an obvious, but important, physical manifestation of prominent views of the catholic church. all is not lost (with or without god), as it can be argued that the church of the epiphany – although miserable to visit and disappointing on the interior paved the religious road for churches to come. 3. kresge chapel if the church of the epiphany embodies a hollowness and, at best, a lacking rewardverging-on-punishment, tidy kresge chapel offers a potent, radiant counterpoint. critics argue that architect eero saarinen’s religious figure 2 – approach to church of the epiphany figure 3 light wells expressed in building massing figure 4 cross-shaped skylight above altar (church of the epiphany) figure 5 yellow glow in upper right coming from lower left (church of the epiphany) 3904/15 | cultura e scienza del colore color culture and science figure 6 yellow glow hitting the parishioners’ bodies (church of the epiphany) figure 7 yellow glow on floor (church of the epiphany) figure 8 light from north-facing window with candle glow in entry spaces “adopted open or centralized plans and iconic forms that unified clergy and congregation, performer and audience” [4]. this intimacy in plan is reiterated in sectional design and material choices to offer the visitor an experience akin to the comforting embrace of a close friend – an escape from worldly affairs and from the intellectual pursuits that abound on a renowned campus such as the massachusetts institute of technology. a visitor approaching kresge chapel from the south naturally follows a prescribed path along a long walk. a strong wall along the east side of the land and a grove of small trees define and favorably isolate the chapel site from the enormous expanse of the university campus. after entering the building, the circulation route to the chapel forces the visitor to take a sharp left through a naturally lit hallway. this physical movement – a sharp turn – encourages a change in perception. a visitor can abruptly leave the day’s trivialities aside, perhaps setting the scene for shifting into a mode to ponder spiritual existence. the hallway wall is covered in nearly monochrome green abstract stained glass, seemingly verdant. upon crossing the threshold into sanctuary space, the ceiling height rises. the area is darker than the adjoining hallway, and eyes must adjust to absorb the essence of the space. the outside goings on of undergraduates and backpacks, mere steps away, feel remote, separate from this interior cavity. here inside, the altar area is lit strong and specific from above. the side lighting seems muted, eerie, almost intangible, and elusive in quality. in only a few paces, there has been a strong shift in light quality and spatial experience. the sanctuary volume itself rests elegantly simple and stoically geometric. the cylindrical building envelope wraps a very small space, approximately 54 feet in diameter [5]. a mere 120 or so seats are set within the space; the chairs are easily movable and, although ordered, do not seem to be ruthlessly arranged. the chairs caned with a rough straw remind of the casual, modest pragmatism of a visit to a scandinavian country cottage in midsummer. the interior feels flexible, not constrained by certain religious dogma, yet still specific, spiritual, and memorable. the interior wall undulates lightly, further exposing prominent textural variations in the texture of the brickwork. with a lack of religious iconography inside the sanctuary itself, the decor consists solely of material color and light variations. once again, as at the church of the epiphany, a light well is located directly above the altar. here, however, the oculus-shaped puncture in the building envelope provides a hotter, buffered yet concentrated light. this light reflects off of the 40 cultura e scienza del colore color culture and science | 04/15 shiny, harry bertoia-designed metallic sculpture streaming down from above. so, too, the marble altar, up on a platform, reflects light off of its smooth shiny whitish surface. (see figure 10.) this combination of color, light, and material leaves the altar area highly charged, giving off a blinding glow. a series of lower light scoops surround the base of the building, allowing light to bounce off of the exterior moat and into the cylindrical volume. the lower windows themselves hide from the view of seated parishioners with a half wall, allowing for the light of the overhead oculus to take the foreground while the moat-reflected light gently illuminates lower portions of the surrounding enclosure. the oculus focuses attention; the lower light wells provide ambient light, a sense of nurturing softness around the sides of the space. for the building’s design, architect saarinen stated that he was looking to recreate a travelling moment in the greek isles. on a night in sparta, he spotted the moon above in combination with a faint illumination along the horizon. saarinen looked to reproduce this “other-worldly sense” here in the kresge chapel experience [6]. the resultant experiential interiorscape shines with light from above and soft enveloping halos from the ground. the small, cylindrical volume of the interior, the quality of light, and the warmth of materials in the sanctuary space create a meditative quality and a soft attitude of inclusiveness, reinforcing the non-denominational principles of this space. 4. analysis comparison to contemporary religious “color containers” in varied geographical locations and time periods can identify precedents, legacies, and effects of the modernist spaces under scrutiny. the breaks in the building envelope (of both kresge chapel and church of the epiphany) clearly reference windows in early churches (from thick walled romanesque cathedrals to lacy gothic monstrosities). the wall punches remind, to be sure, of modernist icons such as le corbusier’s notre dame du haut to contemporary holy venues such as fuksas architects’ gem in folignio, italy [7]. [see figure 11.] indeed, the ceiling punctures at rafael moneo’s iesu church in san sebastian, spain – as in a myriad of sacred shelters including belfatto and pavarini’s new york city venue – float above to illuminate the altar and anciliary chapels [8]. and, tadao ando’s famed glowing gapped cross in the wall at church of light proves a minimalist interpretation of its precedent windowed cross on the sanctuary ceiling plane at the church of the epiphany. (the design also nicely incorporates the religious traditions of facing churches to the east which here “allows for light to pour into the space throughout the early morning and into the day, which has a dematerializing effect on the interior concrete walls transforming the dark volume into an illuminated box”) [9]. this combination of sacred light effects proves fruitful in an edgy, modernist way. these buildings, and many more religious structures, access that modernist sacred space pile of techniques with shining results. projects such as the much lauded crape by steven holl in seattle, washington (1994-1997) blend atmospheric qualities with conceptual qualities to drag the sacred light toolbox solidly into contemporary creative space. the design of this seattle masterpiece focuses on seven light figure 9 – approach to kresge chapel figure 10 light wells from exterior (kresge chapel) figure 11 chapel of st. ignatius by steven holl in seattle, washington) 4104/15 | cultura e scienza del colore color culture and science wells. holl slyly angles the light wells to produce an inventive atmospheric space; light dumps in from above from each of the cardinal directions. to boot, the seven light chutes directly reference the seven tenets of the chapel’s branch of catholicism, highlighting different facets of catholicism than the ones spatially exemplified at the church of the epiphany. the conceptual and experiential results are described as: seven bottles of light in a stone box; the metaphor of light is shaped in different volumes emerging from the roof whose irregularities aim at different qualities of light: east facing, south facing, west and north facing, all gathered together for one united ceremony. each of the light volumes corresponds to a part of the program of jesuit catholic worship. the south-facing light corresponds to the procession, a fundamental part of the mass. the city-facing north light corresponds to the chapel of the blessed sacrament and to the mission of outreach to the community. the main worship space has a volume of east and west light. at night, which is the particular time of gatherings for mass in this university chapel, the light volumes are like beacons shining in all directions out across the campus [10]. the chapel’s design brilliantly reinforces jesuit catholic religious ideologies with built form and light manipulation. just as at kresge chapel, the lighting inspires in both its spirituality and its ethereality: “what makes the interior so arresting and enigmatic are the halos of softly pigmented light sliced through by shocking patches of otherworldly color” [11]. not only does the building’s concept intellectually captivate, but the space haptically fulfuls sensory input channels of those who inhabit it. as such, this magnificent pairing of exquisite space and idea offers intellectual and experiential rewards in divine abundance. 5. conclusion a case-study comparison of the atmospheric effect of the manipulation of color and light of these two american east coast modernist religious spaces provides a toolbox of techniques for use of color and light in contemporary design. (see figure 12.) as outlined above, these techniques can create heightened experiential spaces, manifest a client’s religious ideology, and convey large scale socio-cultural messages. further exploration, outside of the space allotted in this particular paper, could analyse these religious spaces during many times of the day and over the course of all of the seasons in the year. this data could provide a counterpoint to possible weather patterns and varied lighting conditions that may alter visitor experience on more inconsistent visits. exploration of the space during all hours of religious service (and even during the hours occupied by the clergy and staff) could provide a further wealth of information on ritual and use in relation to color and light decisions. critical examination could then extend from the visual analysis methodologies presented here to scientific color and light data collection of units of luminance in conjunction with calculations compensating for sun angles, roofing material surfaces, incoming light from nearby surfaces (such as a mirrored skin of a skyscraper or a snow covered ground), and similar. more words (or possibly volumes of text) are surely needed to tackle the historical iterations of items in the toolbox, as this paper can only gloss over several rich and varied threads of thought. a thorough scouring of western religious buildings throughout the entirety of architectural history could further enlighten on chronological developments and refinements in techniques outlined here, as well as point out some innovative one-off moments or oddities in figure12 – toolkit for sacred light 42 cultura e scienza del colore color culture and science | 04/15 the continuum of religious space design. as more chromatic explorations launch in mainstream contemporary architecture and interiors (and as mid-century modernism has become a popular contemporary cultural trend), designers need more wealth and variety in color application for the creation of emotionally loaded spaces. technology forces our world population to have screen-based (and often hand-held) experiences of color and light at a nearly constant frequency. for fulfullment and inspiration, people need physical environments offering tactile and encompassing atmospheric experiences as well. this vein of research builds more robust repertoires of techniques for successfully manipulating color with meaningful intentionality in spiritual and secular spaces of the present day and beyond. bibliography [1] but, first, let us review that the long, culturallyestablished tradition that light = sun = divinity /god/ goodness/glory. to examine just a few of the roots of this narrative tradition, remember that in fairytales, gold is the symbol of good. heros and heroines are gold-haired, wearing gold garb and weaponry, sprinting horseback in metallic forests. even from southern climes where towheads are less common, the fairytale protagonists are frequently blonde. the presence of the coloring and light reflectivity of these golden items symbolizes the radiance of the sun. so, too, in contemporary culture’s modes of storytelling, the hollywood cinema technique of backlighting heros and heroines exemplifies this method of heightening a perception of a figure’s glory and/or goodness [2] [3]. [2] harry m. benshoff, sean griffin. america on film: representing race, class, gender, and sexuality at the movies. malden, ma: blackweel publishing, 2004, p. 236. [3] max lüthi, the fairytale: as art form and portrait of man. translated by joh erickson. bloomington, in: indiana university press, 1984, pp. 13-16. [4] walker art center and minneapolis institute of art, eero saarinen shaping the future, no. 72, minneapolis, mn: walker art center and minneapolis institute of art, june 6, 2008, p. 3. [5] www.kubuildingtech.org. [6] antonio roman, eero saarinen: an architecture of multiplicity. new york: princeton architectural press, 2003, p. 14. [7] http://www.designboom.com andrea db, “doriana fuksas interview”, august 26, 2011. [8] http://www.architectural-review.com/ michael webb. “raphael moneo’s iesu church in san sebastian.” [9] http://www.archdaily.com/ andrew kroll, ad classics: church of the light/tadao ando, january 6, 2011. [10] http://www.stevenholl.com/ [11] http://www.stevenholl.com/ quoting sheri olson from architectural record, july 1997. cultura e scienza del colore color culture and science 12 cultura e scienza del colore color culture and science | 03/15 1chiara burattini chiara.burattini@uniroma1.it 1franco gugliermetti franco.gugliermetti@uniroma1.it 1mario marchetti mario.marchetti@uniroma1.it 1fabio bisegna fabio.bisegna@uniroma1.it 1dip. diaee, “sapienza” università di roma il ruolo del colore nel progetto di un modulo abitativo per la stazione spaziale internazionale 1. introduzione al di fuori dell’atmosfera, l’ambiente spaziale presenta sostanziali differenze rispetto a quello terrestre; alcune di queste, come il vuoto e l’ossigeno atomico, sono rese prive di effetto con la costruzione di un habitat spaziale, mentre altre, come le radiazioni e l’assenza di gravità, esplicano i loro effetti anche all’interno di ambienti artificiali appositamente costruiti per la vita nello spazio [1]. molte sono le conseguenze, soprattutto di natura fisiologica, che la microgravità ha sull’essere umano: la letteratura riporta sia problemi persistenti per tutto il periodo di permanenza nello spazio, sia problemi temporanei che spariscono dopo un periodo di adattamento di qualche giorno [2] [3]. durante i primi giorni nello spazio gli astronauti soffrono di malessere dovuto al funzionamento del sistema vestibolare: i sensori del sistema otolitico situati nella parte interna dell’orecchio, non percependo lo stimolo gravitazionale, generano disorientamento e nausea, mentre i movimenti della testa, stimolando il canale semicircolare, provocano vertigini [4]. fin dalle prime esperienze in orbita, gli astronauti hanno raccontato di aver sperimentato quella che è stata definita “inversion illusion”, ossia la sensazione di stare all’interno di un veicolo che vola costantemente capovolto a testa in giù, sensazione che viene meno sedendo saldamente su una sedia e che normalmente sparisce dopo i primi giorni in orbita [5]. tra gli effetti permanenti causati della microgravità ci sono quelli legati all’orientamento degli astronauti, provocati dalla fluttuazione all’interno dei veicoli spaziali di qualsiasi oggetto o persona non ancorati alle pareti. le conseguenze possono sembrare banali, ma l’assenza di gravità rende un ambiente spaziale profondamente differente rispetto a quelli cui siamo abituati sulla terra, soprattutto per ciò che concerne gli aspetti percettivi. non essendo presente la forza che tiene ancorati al suolo, nello spazio non si è vincolati da un asse verticale predefinito ed univoco, ma esistono assi relativi che si modificano di volta in volta in funzione dei movimenti e delle rotazioni di ogni singolo astronauta [6]. il concetto di pavimento, soffitto e pareti laterali perde di significato perché le superfici di un ambiente sono tutte indifferenti tra loro e cambiano continuamente identità: il pavimento è di volta in volta quello che l’astronauta ha sotto i suoi piedi ed il soffitto quello sopra la sua testa. questo permette di sfruttare tutte le superfici interne nella loro interezza per posizionare apparecchiature ed oggetti perché qualsiasi punto diventa accessibile all’equipaggio, ma allo stesso tempo crea ambiguità perché le pareti si confondono tra loro provocando disorientamento negli astronauti. l’effetto si amplifica al passaggio da un modulo all’altro quando questi sono orientati in maniera differente e nei nodi, dove vi sono collegamenti in tutte e sei le direzioni dello spazio: queste circostanze causano nell’astronauta la “visual reorientation illusion” (vri), descrivibile come lo sgradevole effetto che si prova all’ingresso in un ambiente conosciuto da una direzione inusuale o quando si perde il senso dell’orientamento [7]. la sensazione sparisce una volta che la persona si è ruotata, posizionandosi correttamente: in questo sono di aiuto le irregolarità dello spazio interno, la posizione degli oggetti, ma soprattutto può agevolare la colorazione delle superfici. studi precedenti, condotti in laboratorio [8] o con l’ausilio della realtà virtuale [9] [10], hanno ampiamente dimostrato l’influenza del colore sulla capacità di orientamento dell’essere umano: in ciascun esperimento è stato evidenziato come il riconoscimento della spazialità di un ambiente sia facilitato da connotazioni colorate rispetto alle situazioni in cui tale connotazione è assente. in particolare, aoki et al. [11], hanno indagato l’effetto dell’arredamento sull’orientamento umano in uno spazio virtuale che riproduce le caratteristiche tipiche di una stazione spaziale con moduli connessi tra loro in varie direzioni, dimostrando che l’uomo perde l’orientamento muovendosi in uno spazio tridimensionale totalmente vuoto ed uniforme, mentre si orienta correttamente quando le superfici assumono colorazioni differenti. l’uso del colore negli ambienti interni è inoltre un ottimo espediente per combattere i problemi psicologici che si verificano durante lunghi periodi di confinamento [12] [13] come le missioni spaziali odierne ed ancor di più lo saranno le future [14]: l’inserimento elementi colorati rompe la monotonia di un ambiente perché aumenta gli stimoli sensoriali [15], diminuendo così i momenti di noia che l’isolamento può generare negli astronauti e migliorando l’umore dell’intero equipaggio e 1303/15 | cultura e scienza del colore color culture and science con esso i rapporti interpersonali[16]. ricerche psicologiche hanno anche stabilito che il colore, oltre a migliorare lo stato d’animo delle persone, aumenta le performance cognitive che l’isolamento porta a diminuire [17] [18]: la presenza del colore aumenta l’organizzazione e diminuisce il tempo di ricerca, facilita l’identificazione e l’organizzazione delle informazioni, ma soprattutto accelera l’attività decisionale [19]. 2. l’uso del colore nella storia delle stazioni spaziali la fisionomia dello spazio interno degli ambienti spaziali ha subito profonde trasformazioni dall’inizio dell’era spaziale [20]. i primi veicoli, costruiti tra la fine degli anni ’50 e gli anni ’60, erano navicelle spaziali con dimensioni molto ridotte perché progettate per missioni di breve durata: gli astronauti erano ospitati in piccole capsule fornite esclusivamente dell’equipaggiamento strettamente necessario alla missione e alla sopravvivenza ma privi di qualsiasi comfort [21]. quando negli anni ‘70 gli ambienti spaziali diventano laboratori di ricerca, l’abitabilità diventa un elemento di grande interesse perché gli astronauti soggiorneranno al loro interno per un lungo periodo; a questo cambio di funzione è associato sia un aumento delle dimensioni sia una modifica del layout dovuto all’introduzione di apparecchiature di ricerca e di spazi per il soggiorno dell’equipaggio. il design dello spazio interno è una elemento innovativo presente sia nelle stazioni spaziali statunitensi che sovietiche: gli interni dello skylab [22], disegnati dall’architetto raymond loewy, comprendevano una zona living dove gli astronauti potevano trascorrere il tempo libero e mangiare assieme, dotata di un tavolo triangolare attorno al quale riunirsi ed un oblò dal quale osservare la terra; il design della famiglia di stazioni salyut prima e della mir poi [23], è incentrato sulla separazione degli ambienti tra area di lavoro, soggiorno, zona pranzo, cabine private e sulla differenziazione tra pavimento, soffitto e pareti laterali tramite l’uso di differenti colori per ciascuna superficie. in questa “prima generazione” di stazioni spaziali l’asse verticale di orientamento è definito dall’arredamento interno, che essendo concepito come quello terrestre, caratterizza l’ambiente con oggetti che comunemente siamo abituati a trovare in un interno domestico o lavorativo; le stazioni sovietiche enfatizzano maggiormente l’orientamento caratterizzando col colore delle pareti la direzionalità verticale. la stazione spaziale internazionale (iss), assemblata in orbita a partire dal 1998 per aggiunta successiva di moduli, vanta una eterogeneità nella fisionomia degli interni, dovuta sia alla differente funzione dei moduli che alla differente concezione della nazionalità di provenienza: i primi moduli lanciati in orbita, zarya e zvezda, sono di tecnologia russa ed hanno una funzione rispettivamente di cargo e di soggiorno, mentre i successivi sono nodi collegamento (unity, harmony, tranquillity) o laboratori di ricerca (destiny, columbus, kibo) di fabbricazione statunitense europea e giapponese. i moduli russi (figura 1) hanno ereditato la concezione spaziale delle precedenti stazioni sovietiche, con una particolare attenzione al comfort interno, all’abitabilità degli spazi, e all’orientamento degli astronauti: ancora una volta per facilitare la direzionalità dei moduli le superfici interne sono state colorate differentemente (soffitto bianco, pavimento marrone, pareti verdi) [24]. i nodi (figura 2) ed i laboratori hanno una configurazione asettica, con interni completamente bianchi da cui spiccano gli agganci di colore blu anodizzato [25], e una concezione modulare che suddivide le superfici in armadi di dimensioni standard dove sono alloggiati gli strumenti di ricerca: l’indifferenza tra le pareti interne di questi moduli permette agli astronauti di lavorare su qualsiasi superficie, figura 1 interno del modulo zvezda. foto pubblicata nel sito ufficiale della nasa www.nasa.gov figura 2 interno del nodo 2 harmony. foto pubblicata nel sito dell’asi www.asi.it 14 cultura e scienza del colore color culture and science | 03/15 longitudinale, con due elementi di accesso posti in corrispondenza delle circonferenze terminali, ed un corridoio centrale a sezione rettangolare che si snoda per tutta la lunghezza del cilindro, sul quale si aprono le porte dei singoli scompartimenti, quattro per ogni lato [31]. lo spazio interno ha una configurazione simile ai moduli di fabbricazione statunitense caratterizzato dalla ripetitività degli elementi e con due assi di simmetria, uno longitudinale ed uno trasversale, che tagliano l’ambiente in due parti speculari (figura 3): senza dare alcuna connotazione agli elementi che caratterizzano il corridoio centrale, ma lasciando tutte le pareti bianche con maniglie ed agganci blu, secondo le prescrizioni della nasa, lo spazio diventa un labirinto all’interno del quale non è possibile capire quale sia il corretto orientamento verticale relativo. con una simile configurazione, entrando nel modulo, gli astronauti si trovano senza punti di riferimento e non possono distinguere il soffitto dal pavimento, né gli scomparti localizzati a destra da quelli a sinistra e quindi non sono in grado di dirigersi con certezza verso il proprio alloggio. similmente, in caso di pericolo che richieda l’evacuazione verso una direzione precisa, l’equipaggio avrebbe difficoltà a dirigersi verso l’uscita corretta. una possibile soluzione adottabile è quella di utilizzare delle indicazioni scritte: per l’orientamento spaziale si dovrebbero utilizzare diciture quali “up”, “down”, “right” “left”, “front”, “back”, e per il riconoscimento della cabina un numero o il nome di ciascun astronauta posto sulla porta relativa. tale metodo presenta però delle criticità che non lo rendono ottimale perché la leggibilità delle scritte non è immediata, anzi risulta difficoltosa se queste sono posizionate sottosopra o lateralmente rispetto all’osservatore o se troppo piccole. una precedente ricerca [32] ha dimostrato che l’utilizzo di indicazioni scritte contenute all’interno di riquadri colorati rende più facile e veloce l’orientamento degli astronauti rispetto a quanto avvenga in un modulo senza scritte; la stessa ricerca ha rilevato come la tipologia di interni russi siano più funzionali all’attività figura 4 modulo di studio con assi di simmetria: pianta e prospettiva anche pavimento o soffitto, e di disporsi a loro piacimento, anche a testa in giù o in orizzontale perché nessuna direzionalità prevalente è imposta e l’asse verticale può essere individuato unicamente facendo riferimento alla posizione delle sorgenti luminose; inoltre la concezione modulare implementa il grado di libertà perché permette agli astronauti di disporre a proprio piacimento gli oggetti, direzionandoli nel modo di volta in volta più comodo. questo tipo di concezione dello spazio interno, pur essendo molto funzionale dal punto di vista operativo, è poco confortevole per chi deve vivere al suo interno alcuni mesi: lo spazio diventa labirintico per l’essere umano che si è evoluto orientandosi in funzione della gravità terrestre, perché la totale uniformità è causa di perdita di orientamento. molte sono state le proposte di aumentare il grado di abitabilità e di comfort dello spazio interno delle stazioni spaziali ponendo maggiore attenzione alle esigenze di chi vive (e non solo opera) al suo interno [26] [27] [28] [29] rispetto agli standard prefissati astrattamente dalle agenzie spaziali [30]: una delle indicazioni più ricorrenti è quella di fare uso del colore al fine di rendere l’ambiente meno monotono ma soprattutto per agevolare l’interazione dell’essere umano con l’ambiente facilitandone i movimenti e gli spostamenti all’interno del modulo o da un modulo all’altro. il presente lavoro si propone di analizzare le possibili soluzioni adottabili per facilitare l’orientamento dell’essere umano in uno spazio extra-atmosferico come la stazione spaziale internazionale dove la gravità è assente: come mezzo di indagine si è utilizzato un ipotetico ambiente tridimensionale progettato e modellato come un prototipo di modulo abitativo 3. il progetto del colore di un modulo spaziale il modello utilizzato per lo studio è un piccolo habitat contenuto all’interno di un cilindro del diametro di 3,85 m e lungo 13,65 m che accoglie gli alloggi personali per gli astronauti: il modulo ha una distribuzione secondo l’asse 1503/15 | cultura e scienza del colore color culture and science di orientamento rispetto a quelli americani ed europei, perché un maggior numero di soggetti riesce a posizionarsi correttamente rispetto all’orientamento del modulo e soprattutto in minor tempo. é dunque una buona strategia applicare la concezione russa sullo spazio interno al modulo abitativo sperimentale, soprattutto per ciò che attiene l’uso dei colori per caratterizzare le superfici. nella scelta della tinta da abbinare alle pareti è bene fare riferimento a quelle comunemente utilizzate sulla terra, quindi colorazioni scure (rho < 0,3) per il pavimento, molto chiare per il soffitto (rho > 0,8) e pastello (rho ≈ 0,65), tenendo però presente che in un ambiente spaziale la percezione del colore cambia per effetto della microgravità: è stato dimostrato che la sensibilità dell’occhio umano aumenta alle lunghezze d’onda corte e diminuisce alle lunghezze d’onda lunghe, che il giallo è percepito più saturo e che la luminosità diminuisce [33]. le colorazioni più appropriate sono risultate il marrone (s 3040-y40r) per il pavimento, bianco panna (s 0505-y10r) per il soffitto, verde (s 0540-g30y) e celeste (s 0520-b10g) per le pareti laterali: la rappresentazione grafica dei colori indicati con la rispettiva catalogazione nel sistema natural color system (ncs) [34] è mostrata in figura 4. le tinte sono state scelte tenendo in considerazione la funzione abitativa del modulo e dunque con la finalità soddisfare la connessa necessità di rendere l’ambiente rilassante e confortevole: il marrone della pavimentazione crea un rimando al legno, un materiale legato al calore e all’intimità della casa, che usualmente viene utilizzato negli interni domestici per la superficie di calpestio; il celeste ed il verde sono entrambe tinte fredde, che generano uno stato di tranquillità nell’essere umano e dunque adatte ad un ambiente di riposo, mentre il bianco è una colorazione neutra che non ha effetti sullo stato d’animo e normalmente viene utilizzata per il soffitto. il marrone, il verde ed il celeste sono i tre colori maggiormente presenti nella natura, che l’essere umano è abituato ad osservare quotidianamente; la loro presenza negli interni spaziali fornisce agli astronauti una stimolazione sensoriale che normalmente proviene dall’ambiente esterno terrestre, altrimenti non presente nello spazio. lo stimolo proveniente dal colore ha effetti psicologici che producono risvolti positivi sul soggiorno spaziale: oltre a migliorare l’umore, i colori aiutano a contrastare la sensazione di isolamento e lontananza che gli astronauti provano, soprattutto nelle missioni di lunga durata. applicando una colorazione uniforme alle pareti laterali non è però possibile identificare con immediatezza ciascuno scompartimento: una possibile soluzione è quella di assegnare a ciascuno di essi una differente gradazione del colore della parete, ad esempio cambiandone la saturazione. una soluzione altresì efficace per caratterizzare la porta delle cabine personali è quella di posizionare su ciascuna di esse una figura differente, come può essere un elemento geometrico, o un simbolo universalmente noto, ma comunque molto semplice in modo da poter essere riconosciuto da qualunque prospettiva; la tecnica di affiancare segni grafici elementari ai colori nella segnaletica è stata studiata come mezzo efficace in alcuni contesti pubblici dove l’uso del solo colore risulta limitante [35]. esempi di figure adatte possono essere un triangolo, un cerchio, o una stella; utilizzando del velcro le figure possono essere facilmente attaccate e staccate dalla superficie cosicché ogni singolo astronauta possa scegliere la propria figura da apporre sulla porta della sua cabina, in modo da personalizzarla ed aumentare così il senso di appartenenza. per poter apparire efficacemente rispetto al colore della parete, la figura dovrà avere una colorazione che produca un forte effetto di contrasto con lo sfondo: il bianco sembra una scelta idonea e sobria perché non aggiunge una ulteriore tinta in una stanza già carica di colore. per poter essere identificati con immediatezza in una stanza colorata, ugualmente bianchi dovranno essere gli agganci e le maniglie che servono agli astronauti per spostarsi ed ancorarsi ed i giunti di connessione tra i moduli. la gradazione di colore delle pareti laterali è stato invece indicato come uno strumento utile per enfatizzare la direzionalità verticale del figura 4 le colorazioni nel sistema ncs 16 cultura e scienza del colore color culture and science | 03/15 modulo [26]: passare da una saturazione minore a contatto col pavimento ad una saturazione sempre maggiore per giungere a livelli di luminanza sempre crescenti a contatto col soffitto è certamente una soluzione utile per facilitare maggiormente il corretto posizionamento degli astronauti all’interno del modulo. tale metodologia di progettazione produce le finalità sopra descritte anche in un interno in cui è presente un basso livello di illuminamento, perché i colori indicati possono essere distinti dall’occhio umano anche con i 50 lux che sono normalmente presenti negli interni della iss. 4. conclusioni il colore è diventata un’esigenza irrinunciabile per la progettazione delle future stazioni spaziali perché svolge un ruolo centrale ed imprescindibile all’interno degli habitat extraatmosferici migliorando il grado di comfort e di abitabilità rispetto ai moduli attuali. con il presente studio si è voluto produrre un primo esempio di come potrebbero essere i futuri moduli spaziali se progettati utilizzando il colore in modo utile alle esigenze di chi fruisce dello spazio e finalizzato all’obiettivo di semplificare gli spostamenti ed i movimenti all’interno dell’ambiente. la progettazione di una intera stazione spaziale richiede la necessità di affrontare di volta in volta la definizione di ciascun modulo o di ciascun ambiente ed in funzione delle caratteristiche specifiche studiare la soluzione più corretta, soprattutto per risolvere le singole particolarità che ogni tipologia di modulo presenta. l’obiettivo del presente studio è stato quello di indicare un modello progettuale, delle linee guida che indirizzano verso una corretta progettazione di habitat spaziali per mezzo del colore: • caratterizzare ogni superficie non un colore differente, scegliendo una tinta appropriata; • graduare la colorazione delle superfici verticali modulando la saturazione e la luminanza; • evidenziare gli elementi rilevanti e di sicurezza in bianco. sarà possibile verificare l’efficacia della soluzione ipotizzata nella sua capacità di agevolare l’orientamento e l’individuazione degli scompartimenti testando la risposta dell’essere umano in un ambiente tridimensionale simulato con realtà virtuale, oppure applicando il progetto in uno dei moduli della iss. bibliografia [1] m. d. griffin, j. r. french, “space vehicle design”, aiaa education series, 2004. 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[34] www.ncscolur.com [35] g. bertagna, a. bottoli, “colori, segni, convenzioni e daltonici”, cultura e scienza del colore – color culture and science (2014), 01, p. 13 15. cultura e scienza del colore color culture and science 38 cultura e scienza del colore color culture and science | 02/14 with acetone. two samples of each alloy were exposed to an urban pollution in the faculty of engineering of sapienza university of rome and two for each alloy to a marine environment in a coastal town (fiumicino) from january to april 2011. the samples were oriented towards the south and had an inclination of 45° following iso 9223 [10]. under these conditions colorimetric variations were measured every two weeks for the urban samples and every month for the marine samples. in addition in the laboratory a third set of samples was exposed to wet and dry cycles of acid rain and marine spray (the composition of both solutions is listed in table 1 [11-12]) for a total of 0.66 ml of vapour per cycle in a volume of 45 cm3. the temperature was kept at 20°c. colorimetric measurements were done on six samples of each alloy after 2 hours, 4 hours, 24 hours, 48 hours, 96 hours and 240 hours. 3. methods the colorimetric measurements were carried out with a portable sphere spectrophotometer. the spectrophotometric measurements were performed in spin (specular component included) mode, with d65 illuminant and 10° standard observer. the reflected light percentage (%) was measured as a function of the wavelength (nm) in the visual spectrum. in correspondence to wavelengths between 400 and 700 nanometers, the spectrophotometer reports spectral data (percentage of reflected light) every 10 nm. the colour difference (de) between two measurements is based on the l*, a* and b* values as follows: de = √(dl*)2 + (da*)2 + (db*)2 [5] 1. introduction and research aim metals have had in the past and still have nowadays many applications. one of the oldest and most frequently used metals has been copper and one of its alloys: bronze, which is copper and tin alloy. bronze is often used because of its good mechanical properties and for its colour range when corroded, which can give different aesthetic results to the artifacts. the colour of bronze depends on the concentration of the main components and any additional alloying elements. not only gives the composition a specific colour to the alloy, it also influences the corrosion behaviour. this research focuses on the correlation between urban and marine environments and the corrosion behaviour of three bi-component copper-tin alloys used in different historical and artistic artifacts using colorimetry. colorimetric measurements are useful because they are non-destructive and can be done using compact instruments, which are portable, implying that in-situ measurements can be done in a relatively rapid manner [1]. in addition spectrocolorimetry can detect the copper content in quasi-binary bronzes [2] and can assess the condition of metallic findings and their mineralization degree [3-4]. the characterization of bronze patina, with a possible link to a variable thickness of the layer or to a different corrosion mechanism, has also been studied [5-8]. in this work colorimetric measurements are used as a means to study the influence of the tin content on the corrosion behaviour of the bronze samples and to understand the corrosion kinetics. 2. materials, samples preparation and exposure three bronze alloys were selected to represent historical and artistic artifacts, with a tin concentration of 3%, 7% and 20% respectively [9]. the surfaces of the bronze coupons (diameter 12.5 mm) was ground/polished with abrasive papers of 400–1200 grades. they were then cleaned with sulphuric acid at 10%v/v, rinsed with distilled water and degreased 1-2liliana gianni, liliana.gianni@uniroma1.it 1annemie adriaens, annemie.adriaens@ugent.be 2mauro cavallini, mauro.cavallini@uniroma1.it 2stefano natali, stefano.natali@uniroma1.it 2valerio volpe, valerio.volpe@uniroma1.it 2laura zortea laura.zortea@uniroma1.it 1dept. of analytical chemistry ghent university 2dicma, sapienza università di roma reflectance curves and cie l* a* b* parameters to describe patina characteristics and corrosion mechanism on bronze alloys acid rain (mg dm3) marine spray (g/dm3) h 2 so 4 (96%) 31.85 nacl 23,5 (nh 4 ) 2 so 4 46.20 kbr 0.1 na 2 so 4 31.95 kcl 0.7 hno 3 (70%) 15.75 cacl 2 1.3 nano 3 21.25 na 2 so 4 4 nacl 84.85 mgcl 2 * 6h 2 o 10.7 3902/14 | cultura e scienza del colore color culture and science 0 2 4 6 8 10 12 14 16 18 20 0 2 4 6 8 10 6 9 12 15 18 21 24 27 3% of tin 7% of tin 20% of tinw ee ks b* a* urban 400 450 500 550 600 650 700 0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 corrosion test: 7% samples exposed to urban environment r% l/nm clean 2 weeks 4 weeks 6 weeks 8 weeks 10 weeks (c) one must note that the de equation was originally designed for calculating small differences (de<10). higher values obtained here will be considered only for comparative purpose. all together with this numerical colour identification the aim is to asses the degradation levels of the three alloys exposed to natural and artificial environments and the corrosion kinetics. this is done by correlating the abovementioned colour parameters with the patina quality and growth. 4. experimental 4.1. urban environment exposure the samples exposed to the urban environment produce a brown/black patina in a few days. 400 450 500 550 600 650 700 0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 corrosion test: 3% samples exposed to urban environment r% l/nm clean 2 weeks 4 weeks 6 weeks 8 weeks 10 weeks (a) figure 1 reflectance curves for samples with (a) 3%, (b) 7% and (c) 20% of tin exposed to an urban environment from january to april 2011. 400 450 500 550 600 650 700 0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 corrosion test: 7% samples exposed to urban environment r% l/nm clean 2 weeks 4 weeks 6 weeks 8 weeks 10 weeks (b) the reflectance curves as a function of time are shown in figure 1 for the three samples. the difference in reflectance curves for the 3% and 7% samples is relatively large between no exposure and two weeks of exposure, indicating that the surface immediately becomes matt or textured upon exposure. the variation becomes less significant with increasing exposure time. the samples containing 20% tin, on the other hand, seem to have undergone the least damage, in that regard that the reflectance curves show a decrease but not as large as the other two samples. these data are confirmed by the lightness and de values which show a large decrease during the first weeks for the 3% and 7% samples and much less for the 20% sample (figure 3b; table 1: 3% of tin sample exposed to urban environment l* a* b* δe clean 83.63 10.35 14.17 37.06 2 weeks 49.48 18.21 26.24 9.82 4 weeks 45.12 12.78 19.31 10.94 6 weeks 45.15 6.11 10.63 2.67 8 weeks 44.68 8.37 11.97 7.11 10 weeks 40.51 4.77 7.46 table 2: 7% of tin sample exposed to urban environment l* a* b* δe clean 84.07 8.26 14.63 25.50 2 weeks 59.58 6.98 21.64 6.61 4 weeks 53.16 6.14 22.96 2.55 6 weeks 55.7 6.32 22.77 2.79 8 weeks 54.48 6.25 20.26 9.21 10 weeks 49.61 4.01 12.76 table 3: 20% of tin sample exposed to urban environment l* a* b* δe clean 81.76 2.99 11.94 9.85 2 weeks 76.44 5.29 19.91 8.95 4 weeks 68.35 4.34 16.18 3.31 6 weeks 65.65 2.46 16.59 3.09 8 weeks 65.99 1.84 13.58 3.05 10 weeks 63.23 1.27 14.76 b)a) figure 3 the ciel* a* b* parameters detected for the samples exposed to urban environment. a) a* and b* parameters plotted vs exposure time; b) tables of l*, a*, b* and de for the three alloys. 40 cultura e scienza del colore color culture and science | 02/14 350 400 450 500 550 600 650 700 750 0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 (a) corrosion test: 3% samples esposed to acid rain vapor r% l/nm clean 2h 4h 24h 48h 96h 240h table 1-3). in addition the de values show for the 3% and 7% samples an increase during the ninth week, which indicates that the first patina formed slows down the corrosion process that restarts during the ninth week. from the de values decreases we can deduce that the patinas formed on the 20% tin samples progressively slow down the corrosion process (figure 3b; table 3). nevertheless, also here the largest difference in colour values of the corrosion products can be deduced from l* and de values between the clean alloy and after the first weeks. this difference indicates a fast oxide passivating layer formation. the colour parameters can be correlated with patina quality and growth: the advanced corrosion of the 3% alloy is shown by the l*, a* and b* compared with the 7% and 20% of tin parameters. the kinetic aspects are correlated to the fact that the de values of 3% tin samples are larger than for the other alloys (figure 3b; tables 1-3). 4.2. acid rain vapour in the corrosion chamber in the laboratory environment, the colour evolution of the three alloys was examined while being exposed to acid rain vapour for 10 days. the reflectance curves as a function of time are shown in figure 2, while the values of the lightness and colour are reported in the tables 1 through 3 of figure 4b. the reflectance curves show a similar trend, though with a smaller dynamic range, as for the urban environment: a relatively large difference between no exposure and two hours of exposure for the 3% and 7% samples (after which the curves seem to stabilize) and only a small variation for the 20% sample. the latter demonstrates again that the 20% samples seem to be the less attacked: the reflectance values are higher and the de values are lower than for the other samples, as is shown in figure 2 and in the tables of figure 4b. the differences detected by the reflectance, lightness, a* and 350 400 450 500 550 600 650 700 750 0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 (b) corrosion test: 7% samples exposed to acid rain vapor exposition r% l/nm clean 2h 4h 24h 48h 96h 240h 350 400 450 500 550 600 650 700 750 0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 (c) corrosion test: 20% samples exposed to acid rain vapor exposition r% l/nm clean 2h 4h 24h 48h 96h 240h figure 2 reflectance curves for samples with (a) 3%, (b) 7% and (c) 20% of tin exposed to acid rain vapour respectively for 2, 4, 24, 48, 96 and 240 hours. 2 4 6 8 10 12 14 16 0 25 50 75 100 125 150 175 200 225 250 5 10 15 20 25 3% of tin 7% of tin 20% of tin h ou rs b* a* a) table 1: 3% tin sample exposed to acid rain vapour l* a* b* δe 0h 83.63 10.35 14.17 22.78 2h 61.06 12.38 19.73 4.95 4h 62.66 15.25 23.44 8.83 24h 56.26 11.54 18.61 5.53 48h 53.26 11.07 13.98 7.32 96h 49.31 9.39 8.05 5.22 240h 44.57 10.98 6.53 table 2: 7% tin sample exposed to acid rain vapour l* a* b* δe 0h 84.07 8.26 14.63 16.32 2h 73.31 11.3 26.52 8.56 4h 64.85 11.21 25.18 10.19 24h 54.92 12.6 27.04 2.83 48h 54.48 11.43 20.56 4.53 96h 51.38 9.79 12.4 3.57 240h 49.55 9.88 9.33 tab 3: 20% tin sample exposed to acid rain vapour l* a* b* δe 0h 81.76 2.99 11.94 4.99 2h 78.71 4.35 15.65 3.78 4h 81.17 3.21 13 7.56 24h 74.09 4.42 15.38 2.63 48h 76.36 3.74 14.23 3.05 96h 75.45 4.64 17.4 7.36 240h 68.48 4.1 15.09 b) figure 4 the ciel* a* b* parameters detected for the samples exposed to acid rain vapour. a) a* and b* parameters plotted vs exposure time; b) tables of l*, a*, b* and de for the three alloys 4102/14 | cultura e scienza del colore color culture and science b* measured on the alloys (figure 4b; tables 1-3) are due to the composition and physicalchemical property of the patinas. a comparison between the natural environment and the artificial one is possible with the samples of the second week and of the 240th hour (corresponding to ten days) if some caution is taken. for the 3% samples the lightness values reduction is bigger in the laboratory test (49.48 vs 44.57) while the a* values increases for both samples but more significant for the natural corrosion (18.21 vs 10.98). also the b* (26.24 vs 6.53) is bigger for the sample exposed to acid rain vapour. that means there is a patina more formed on the sample exposed to acid rain vapour because of higher red and yellow values and lower lightness. the 7% sample shows a big difference for the l* (59.58 vs 49.55) and the b* (21.64 vs 9.33). also in this case the sample exposed to laboratory test shows a patina more developed. however the differences between the two patina are less accentuated for the colour parameters than in the 3% samples. the 20% samples maintain a rather similar colour patina 400 450 500 550 600 650 700 0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 corosion test: 3% exposed to marine envoronment r% l/nm clean 1 month (a) 400 450 500 550 600 650 700 0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 corrosion test: 7% exposed to marine environment r% l/nm clean 1 month (b) 400 450 500 550 600 650 700 0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 corrosion test: 20% exposed to marine environment r% l/nm clean 1 month (c) figure 5 reflectance curves for samples with (a) 3%, (b)7% and (c) 20% tin exposed to marine environment from january to april 2011. -6 -4 -2 0 2 4 6 8 10 12 0 1 2 0 2 4 6 8 10 12 1416 3% of tin 7% of tin 20% of tin m on th s b*a* a) b) 3% tin sample exposed to marine environment l* a* b* δe clean 83.63 10.35 14.17 29.37 1 month 58.69 -1.49 4.16 4.31 2 months 56.3 -3.1 0.95 7% tin sample exposed to marine environment l* a* b* δe clean 84.07 8.26 14.63 29.95 1 month 59.99 -5.24 3.01 7.01 2 months 53.23 -3.4 2.86 20% tin sample exposed to marine environment l* a* b* δe clean 81.76 2.99 11.94 22.42 1 month 62.45 -6.01 4.94 3.74 2 months 60.47 -2.86 5.3 4.3 marine environment exposure the colour measurements for the marine environment were performed once per month. figure 5 shows the reflectance values for the first two months of exposure. the patinas formed in this environment have a characteristically green colour due to the chloride presence in the marine environment. in the 3% of tin samples the green grows continuously whilst for the 7% and 20% it decreases in the second month as a* values underline (figure 7; tables1-3). nevertheless the green colour remains always more accentuated than in the 3%. different in comparison to the samples exposed to the urban environment, the cie l*a*b* parameters for the marine environment are very similar in the three alloys. this happens because of the strong aggressiveness of the marine environment that has the same effects on the surfaces, also in the presence of tin that generally has a good corrosion resistance. the de differences between the three alloys are less than in the tests before but also in this environment the smaller difference colour is on the 20%. figure 7 the ciel* a* b* parameters detected for the samples exposed to marine environment. a) a* and b* parameters plotted vs exposure time; b) tables of l*, a*, b* and de for the three alloys. 42 cultura e scienza del colore color culture and science | 02/14 4.4 marine spray vapour in the corrosion chamber in the vapour chamber the three sets of samples were sprayed with synthetic marine water for ten days. the colour measurements were taken at the same time intervals as was done for the synthetic acid rain vapour tests. the optical microscopy images and the reflectance curves are shown in figure 6. the surface patinas are not homogeneous and exhibit patches of different dimensions on inner corrosion layer. spectrocolorimetric measurements are performed on small areas and in this case different spots are present. results of the instrument are therefore the integration of values of each colour contribution. in the first hours of exposure the reflectance shows dominant values in the green region because the chloride patinas are immediately formed. the 3% samples in the area analysed have less patches despite inversion of the reflectance values. samples containing 7% of tin undergo a larger attack in the first 4 hours. 20% samples have higher reflectance values than the other alloys, which may indicate they are less prone to corrosion, nevertheless the samples always present green spots from the first exposition. the de value is strongly affected by the patina inhomogeneity as is the case for the other parameters. it is possible to extract only an indicative evaluation that shows a smaller difference in colour for all the 20% samples compared to the 3% and 7%. the 7% samples present always more colour differences (figure 8b). 5. conclusions the colour measurements are able to demonstrate the patina formation with a good sensibility also for the first steps, which cannot be evaluated with visual analyses. the difference in colour between two measurements gives an idea about the kinetics of the corrosion process, whilst the reflectance and lightness values can be correlated to the layer growth. the a* and b* values are associated with the patina composition. the study shows the 400 450 500 550 600 650 700 0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 (a) corrosion test: 3% samples exposed to marine vapor r% l/nm clean 2h 4h 24h 48h 96h 240h 400 450 500 550 600 650 700 0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 (b) corrosion test: 7% samples exposed to marine vapor r% l/nm clean 2h 4h 24h 48h 96h 240h 400 450 500 550 600 650 700 0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 (c) corrosion test: 20% samples exposed to marine vapor r% l/nm clean 2h 4h 24h 48h 96h 240h figure 6 reflectance curves for samples with (a) 3%, (b) 7% and (c) 20% tin exposed to marine spray respectively for 2, 4, 24, 48, 96 and 240 hours. -12-10 -8 -6 -4 -2 0 2 4 6 8 10 12 0 25 50 75 100 125 150 175 200 225 250 0 5 10 15 20 25 30 3% of tin 7% of tin 20% of tin h ou rs b*a* a) b) figure 8 the ciel* a* b* parameters detected for the samples exposed to marine vapour. a) a* and b* parameters plotted vs exposure time; b) tables of l*, a*, b* and de for the three alloys 3% tin sample exposed to marine vapour l* a* b* de 0h 83.63 10.35 14.17 23.02 2h 61.33 5.7 17.55 4.89 4h 64.52 6.41 21.19 6.17 24h 59.58 10.06 21.81 6.15 48h 57.86 9.04 15.99 3.20 96h 54.84 10.08 15.77 13.34 240h 57.16 -2.74 12.93 7% tin sample exposed to marine vapour l* a* b* de 0h 84.07 8.26 14.63 14.30 2h 75.11 -0.1 22 12.05 4h 69.5 8.48 28.34 10.58 24h 62.08 4.87 21.72 7.09 48h 64.41 10.99 24.44 6.50 96h 62.81 4.71 23.94 14.89 240h 62.07 -4.68 12.41 20% tin sample exposed to marine vapour l* a* b* de 0h 81.76 2.99 11.94 9.06 2h 73.13 2.56 14.67 6.03 4h 74.76 0.53 20.11 4.37 24h 70.86 1.48 18.37 8.19 48h 64.46 3.59 23.03 17.14 96h 57.87 -1.39 8.01 9.91 240h 59.87 -10.74 5.39 4302/14 | cultura e scienza del colore color culture and science differences between the corrosion behaviour of three bronze alloys exposed to urban and marine environment. in the urban environment, in both exposition tests, the 3% tin samples are the most attacked especially in the fist time (this is better underlined with the laboratory tests) while the 7% sample has a slower reaction with the environment but the processes goes on as in the 20% that are however less damaged. natural and laboratory exposition reach the same results but the second tests are most focused on the first corrosion products that are the internal layers of the corrosion product of the samples exposed to the natural urban environment. the samples exposed to the marine environment are more attacked than the samples exposed in urban environment. the patina is thick and massive until the first month. the colour depends mainly on the presence of the sodium chloride. the green products are present from the first hours in the laboratory tests. the formation proceeds with separate spots under which are hidden also other corrosion products. the 7% of tin in this environment show more colour difference than the 3% whilst the 20% have the best corrosion behaviour also in this case. bibliography 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[12] a. granic, h. otmacic, e. stupnisek-lisac, m. kharshan, a. furman, “bronze protection in artificial seawater”, meet. abstr. – electrochemical society 902, 1712 (2009) cultura e scienza del colore color culture and science 59 cultura e scienza del colore color culture and science | 10 | 2018 issn 2384-9568 is it possible to improve the weighting function for lightness in the ciede2000 color-difference formula? abstract we have compared the performance of the ciede2000 color-difference formula (∆e00) with three ciede2000-modified formulas: 1) ∆e00_m1, which incorporates a new v-shaped function proposed at the university of leeds (uk) with a minimum at the specific lightness of the background; 2) ∆e00_m2, a formula where the original sl function in ∆e00 was replaced by sl=1, as proposed by the cie94 color-difference formula; 3) ∆e00_m3, a formula developed by us, with the same structure than ∆e00, but avoiding its original sl function by replacing the lightness differences in cielab by a new lightness definition based on whittle formula. our comparison used the stress index and thirteen visual datasets (cie 217:2016), including filtered subsets to test the symmetry of the sl function proposed by ∆e00. none of the three mentioned ciede2000-modified formulas performed statistically significantly better than the original ∆e00 formula for any of the mentioned datasets or subsets, with only one exception (∆e00_m2 formula, witt dataset). therefore, the replacement of the sl function in ∆e00 by sl=1 is not recommended. ∆e00_m1 and ∆e00_m3 improved ∆e00 for most datasets, but such improvements were not statistically significant. results for color pairs with average l* values below and above 50 were not statistically significant different for neither ∆e00, ∆e00_m2 and ∆e00_m3 formulas. it is interesting to note that for eight of the thirteen visual datasets there were no color pairs with average l* values below 25, which claims for future studies using darker color pairs. keywords color difference, color-difference formula, cie94, ciede2000, whittle formula citation: melgosa m., cui g., oleari c., pardo p.j., huang m., li c., luo m. r. (2018) ‘is it possible to improve the weighting function for lightness in the ciede2000 color-difference formula?’, cultura e scienza del colore color culture and science journal, 10, pp. 59-65, doi: 10.23738/ccsj.i102018.07 received 16 july 2018; revised 13 august 2018; accepted 07 september 2018 manuel melgosa is a full professor in optics and current representative of spain at cie divisions 1 and 8. he was secretary, vice-president and president of the color committee of spain (sedoptica). member of the editorial board of the journals color research and application (usa), cultura e scienza del colore (italy), atti della fondazione ‘giorgio ronchi’ (italy), and luces (spain). guihua cui, full professor in colour science, received his b.s. and m.s. degrees in optical engineering from beijing institute of technology (china), and ph.d. degree in colour science from university of derby (uk) in 2000. he was fully involved in the development of the ciede2000 color-difference formula. claudio oleari passed away on january 23rd 2018. emeritus professor at università degli studi di parma, emeritus member of the italian society of optics and photonics (siof), founder and emeritus member of gruppo del colore. editor and co-author of the book “misurare il colore” (hoepli, 2015), and author of the book “standard colorimetry” (john wiley & sons, 2016). pedro j. pardo earned his ph.d. in physics at university of extremadura (spain) in 2004, and currently works as an associate professor at the same university. he served as member of cie tc 1-90 “colour fidelity index” and co-authored cie 224:2017. min huang earned her ph.d. degree in 2008 from national lab of color science and engineering at beijing institute of technology (china). she has undertaken some projects mainly focused on color difference evaluation and colorimetric observer categories and their applications. changjun li is a full professor at the department of computer science, university of science and technology liaoning (china). he received his b.sc. (1979), m.sc. (1982), and ph.d. (1989) in computational mathematics from peking university (china), chinese academy of science, and loughborough university (uk), respectively. ming ronnier luo is a cie vice-president, a full professor at the college of optical science and engineering, zhejiang university (china), a part-time professor at the taiwan university of science and technology, and a visiting professor at the university of leeds (uk). recipient of aic judd award 2017 for his important work in the field of color and imaging science. 1manuel melgosa mmelgosa@ugr.es [corresponding author] 2guihua cui guihua.cui@foxmail.com 3claudio oleari claudio.oleari@fis.unipr.it 4pedro j. pardo pjpardo@unex.es 5min huang huangmin@bigc.edu.cn 6changjun li cjliustl@sina.com 7,8ming ronnier luo m.r.luo@leeds.ac.uk 1 university of granada, department of optics, faculty of sciences, 18071 granada, spain 2 university of wenzhou, department of information & communication engineering, school of physics and electronic information engineering, wenzhou 325035, china 3 università degli studi di parma, department of physics, i-43100 parma, italy 4 university of extremadura, department of physics, faculty of sciences, 06071 badajoz, spain 5beijing institute of graphic communication, beijing 102600, china 6university of science and technology liaoning, school of electronics and information engineering, anshan 114051, china 7zhejiang university, state key laboratory of modern optical instrumentation, hangzhou, china 8university of leeds, leeds ls2 9jt, united kingdom 60 r. cultura e scienza del colore color culture and science | 10 | 2018 | 59 65 melgosa m., cui g., oleari c., pardo p.j., huang m., li c. and luo m. r. issn 2384-9568 doi: 10.23738/ccsj.i102018.07 1. introduction amongst the five corrections to cielab proposed by the current cie-iso recommended colordifference formula ciede2000 (iso/cie, 2014; cie, 2001; luo, cui and rigg, 2001), it can be said that the weighting function for lightness (symbol sl), also called lightness tolerance, has been the most controversial one in recent literature (melgosa et al., 2017). the ciede2000 color-difference formula (symbol ∆e00), proposed a v-shaped symmetrical function sl with a minimum at l *=50 (the assumed lightness of the background), accounting for the so-called ‘crispening effect’. in the current paper, from 13 experimental datasets (7420 color pairs) previously employed by the cie technical committee 1-55 (cie, 2016), we have used the standardized residual sum of squares (stress) index (garcía et al., 2007) to test the performances of the sl function proposed by ciede2000, as well as three ciede2000modified color-difference formulas. low stress values, always in the range 0-100, indicate better performance of a color-difference formula (i.e. better predictions of average visually-perceived color differences reported by real observers with normal color vision). the ciede2000 color-difference formula (iso/ cie, 2014; cie, 2001; luo, cui and rigg, 2001) is given by: , (1) where the three parametric factors will be assumed in this paper as kl=kc=kh=1.0 (i.e. the so-called ‘reference conditions’), and the weighting function for lightness, sl, is given by: . (2) it can be noted that the ciede2000 colordifference formula in eq. 1 is not an euclidean distance, because of the chroma-hue interaction term controled by the rt factor, which is often designated in the literature as the rotation term. the following three ciede2000-modified colordifference formulas will be considered in this paper: 1) the ∆e00_m1 color-difference formula, analogous to ∆e00 in eq. 1, but using the next sl´ function, proposed by researchers at the university of leeds (uk) (ho, 2006): , (3) where lb is the specific cielab lightness of the background for each visual dataset. 2) the ∆e00_m2 color-difference formula, also analogous to ∆e00, but replacing the sl function in eq. 2 by sl = 1, as proposed by the cielab and cie94 (cie, 2004) color-difference formulas. in a recent paper, r.s. berns has recommended to introduce this modification in ciede2000 (berns, 2016). 3) finally, ∆e00_m3 is a color-difference formula recently developed by us (melgosa et al., 2017), with the same structure than ∆e00, but avoiding its original sl function. specifically, the ∆e00_m3 color-difference formula proposes the replacement of the ratio ∆l*⁄sl in eq. 1 by ∆lw , where lw is the next new definition of lightness, based on whittle formula (whittle, 1992): (4) (5) where y is the luminance factor in the range 0-100; i.e. relative colorimetry (cie, 2004). for each one of the 13 visual datasets mentioned before, in addition to the complete datasets we have also considered different subsets: color pairs with almost only lightness differences (specifically, color pairs with│∆l*⁄∆e*ab│>0.9), where ∆e * ab is the color-difference in cielab units), and color pairs with average l* values below and above 50, the assumed lightness of the background in ∆e00 (see eq. 2). table 1 shows the percentage of color pairs in five different subsets, for each of the 13 visual datasets considered here. excluding the two ‘region specific’ datasets with only blue (lee et al., 2011) and black (shamey et al., 2014) color pairs, table 1 shows that the percentage of color pairs below and above l*=50 is balanced well enough (averages of 42.2% vs. 57.8%). however, it is noticeable that the percentage of color pairs with l*≤25 is considerably low: more specifically, table 1 shows that there were 61 cultura e scienza del colore color culture and science | 10 | 2018 | 59 65 is it possible to improve the weighting function for lightness in the ciede2000 color-difference formula? issn 2384-9568 no color pairs with l*≤25 for 9 of the 13 tested datasets, and the percentage in this range was 100% for the ncsu-black (shamey et al., 2014) dataset. 2. results 2.1. complete datasets table 2 shows stress values for each of the 13 visual datasets and different color-difference formulas. specifically, table 2 shows the stress results (garcía et al., 2007; cie, 2016) for the original ∆e00 color-difference formula in column 2, three modifications of this formula previously described (∆e00_m1, ∆e00_m2 and ∆e00_m3) in columns 3-5, and the results found by the original ∆e00 formula modified by a power function with exponent 0.70 (column 6), which produced particularly good results in a previous work (huang et al., 2015). the last two columns in table 2 are the critical f-values to be considered at a 95% confidence level in order to test the statistical significance of the differences between two given color-difference formulas (garcía et al., 2007; cie, 2016). cells filled with blue/yellow color in columns 3-6 of table 2 mean that the formula indicated in the header row performs better/worse than the original ∆e00 formula. in addition, numbers in bold/italic fonts in columns 3-6 of table 2 indicate that there were statistically significant/ non-significant differences (95% confidence level) between the formula in the header row and the original ∆e00 formula. table 1 percentages of color pairs with mainly lightness differences (column 2) and average cielab lightness (l*) in four different intervals (columns 3-6), for each one of the 13 visual datasets considered in this paper. from table 2 it can be noted that for the three ciede2000-modified formulas (columns 3-5) there is only one case with statistically significant better performance than the original ∆e00 formula: the case of the ∆e00_m2 colordifference formula in witt’s dataset (witt, 1999), with a cell filled with blue color and a stress value of 27.4 in bold font. this situation is in contrast with the highly satisfactory results achieved by using a power function with exponent 0.70 in ∆e00 (huang et al., 2015), which produced statistically significant improvements upon the original ∆e00 formula for 9 of the 13 datasets, as indicated by the cells filled in blue color with numbers in bold font in column 6 of table 2. currently, it can be said that the use of power functions is the most effective way to improve the performance of advanced color-difference formulas (huang et al., 2015). 2.2 color pairs with mainly lightness differences table 3 shows analogous results to those in previous table 2, but filtering each one of the original datasets to consider only the color pairs with │∆l*⁄∆e*ab│>0.9 (i.e. color pairs with almost only lightness differences). because we are interested on studying the weighting function for lightness in ∆e00, results shown in tables 2 and 3 allow us to check whether the performances of ∆e00 and the remaining proposed color-difference formulas are or not different for the complete datasets (table 2) and their corresponding filtered subsets with color pairs exhibiting almost only lightness table 2 stress values for 13 visual datasets (column 1) and five color-difference formulas (columns 2-6, see text). cells filled with blue/ yellow colors indicate better/worse performance than the one achieved by using the ∆e00 color-difference formula, while numbers in bold/italic font mean significant/non-significant differences with respect to ∆e00, from specific fc and 1⁄fc critical values shown in last two columns assuming a significance level of 95%. 62 r. cultura e scienza del colore color culture and science | 10 | 2018 | 59 65 melgosa m., cui g., oleari c., pardo p.j., huang m., li c. and luo m. r. issn 2384-9568 doi: 10.23738/ccsj.i102018.07 differences (table 3). from table 3 it can be noted that none of the three ciede2000-modified color-difference formulas (∆e00_m1, ∆e00_m2 and ∆e00_m3) reported statistically significant better results than ∆e00 for any of the 13 datasets (i.e. there are no cells filled in blue color and numbers in bold font in columns 3-5 in table 3). comparing tables 2 and 3, it can be stated that the performance of all tested color-difference formulas (except ∆e00_m3) with respect to the original color-difference formula ∆e00 is slightly worse for color pairs with almost only lightness differences (table 3) than for complete datasets (table 2). from tables 2 and 3 it can be also added that color-difference formulas ∆e00_m1 and ∆e00_m3 (but not ∆e00_m2) improved ∆e00 for most datasets, but such improvements never (except for 1 dataset) were statistically significant. tables 2 and 3 show that for a majority of datasets the ∆e00_m2 formula was significantly or non-significantly worse than the ∆e00 color-difference formula, which indicates that, beside the recommendation made by berns (berns, 2016), for current experimental datasets the replacement of the sl function in ∆e00 by sl=1 is not advisable. table 3 idem to table 2, but for color pairs with mainly lightness differences: │∆l*⁄∆e*ab│>0.9. 2.3. color pairs with average l* below and above 50 in this subsection our goal is to check the symmetry of the sl function proposed by ciede2000 with respect to the assumed lightness of the background, l*=50 (see eq. 2). tables 4 and 5 show stress results found using color pairs in complete datasets with average l* values (l*) below and above 50, respectively. the colors and fonts codes in the cells of tables 4 and 5 are the same used in previous tables 2 and 3. it can be noted that tables 4 and 5 discarded the use of the ∆e00_m1 color-difference formula (and also the ∆e00 color-difference formula modified by the exponent 0.70), because this formula considers the lightness of the backgrounds in each dataset in place of (l*)=50 (ho, 2006). tables 4 and 5 also missed the ncsu-blue (lee et al., 2011) and ncsublack (shamey et al., 2014) datasets because all color pairs in these datasets had (l*) values below 50 (see table 1). from tables 4 and 5 we can see that both, ∆e00_m2 and ∆e00_m3 were never statistically significantly better than ∆e00. it can be also noticed that the performance of these two ciede2000-modified color-difference formulas table 4 stress values for color pairs with average l* values above 50, considering 3 color-difference formulas and 11 visual datasets. the colors of the cells and the fonts for numbers in current table 4 follow the same codes used in previous tables 2 and 3 (see text). table 5 idem to table 4, but for color pairs with average l* values below 50. 63 cultura e scienza del colore color culture and science | 10 | 2018 | 59 65 is it possible to improve the weighting function for lightness in the ciede2000 color-difference formula? issn 2384-9568 with respect to ∆e00 is better for color pairs with l* values below 50 (table 5) than for color pairs with l* values above 50 (table 4), but this result must be interpreted with prudence, because the number of available color pairs in the range l*≤25 is very small (see table 1), and this difference is not statistically significant (see subsection 2.5). 2.4. normalized scatter plots for color pairs with mainly lightness differences figures 1 and 2 show the normalized ratios ∆e*ab⁄∆v for color pairs with │∆l *⁄∆e*ab│>0.9 (i.e. color pairs with mainly lightness differences) against average l* values below and above 50, respectively, for different visual datasets. specifically, we considered 11 visual datasets, discarding from the 13 initial ones (table 1) the two datasets with color pairs in only one region of the color space (lee et al., 2001; shamey et al., 2014). the normalization used in figures 1 and 2 was to divide the mentioned ratios by its average in each individual dataset, as made by berns (berns, 2016). figures 1 and 2 also show the two branches of the sl (v-shaped) function, corresponding to the predictions made by the original ∆e00 color-difference formula (iso/cie, 2014; cie, 2001; luo, cui and rigg, 2001). as in plots reported by berns (berns, 2016), figures 1 and 2 show a considerable scatter. therefore, in general, it cannot be stated that the sl function (eq. 2) proposed by ∆e00 (eq. 1) is a good predictor of experimental results for color pairs with almost only lightness differences in most currently available visual datasets. figure 1 also shows that there are few pairs in the range l*≤25 (see table 1), which claims for future studies using a higher number of dark color pairs. figure 1 normalized ratios ∆e*ab⁄∆v for experimental color pairs with │∆l*⁄∆e*ab│>0.9 (i.e. color pairs with mainly lightness differences) in 11 visual datasets, against average l* values of color pairs in the range 0-50. the predictions made by the ∆e00 colordifference formula are indicated by the black line. figure 2 idem to figure 1, but for color pairs with average l* values in the range 50-100. 64 r. cultura e scienza del colore color culture and science | 10 | 2018 | 59 65 melgosa m., cui g., oleari c., pardo p.j., huang m., li c. and luo m. r. issn 2384-9568 doi: 10.23738/ccsj.i102018.07 2.5. summary of results for complete datasets and subsets table 6 summarizes the results shown in previous tables 2-5, indicating the number of datasets (from a total of 13 or 11, depending on the row considered in such table) with better or worse results than those achieved by the original ∆e00 color-difference formula, considering also statistically and not statistically significant differences at 95% confidence level. note that, for the three ciede2000-modified formulas (∆e00_m1, ∆e00_m2 and ∆e00_m3) statistically significant better results than those found by using ∆e00 were found only for one dataset (witt, 1999). however, the ∆e00 color-difference formula modified by an exponent 0.7 (huang et al., 2015) produced very good results for all complete datasets (i.e. statistically significant or non-significant improvements for all datasets), and also good results for the subsets of color pairs with mainly lightness differences. in general, we can note that highest values in table 6 are located in column 4, which means that for most datasets the ciede2000-modified formulas tested in the current paper were better, but, unfortunately, not statistically significantly better, than the original ∆e00 color-difference formula. with respect to the symmetry around l*=50, it can be noted in table 6 that the ciede2000modified formulas ∆e00_m2 and ∆e00_m3 performed better than the original ∆e00 formula in a majority of datasets for color pairs with average l* below 50, but not for color pairs with average l* above 50. however, from wilcoxon sign rank test, the medians of stress values for color pairs with average l* values above and below 50 (tables 4 and 5) were not statistically significantly different for ∆e00 (p=0.240), ∆e00_m2 (p=0.966), and ∆e00_m3 (p=0.240). 3. conclusions the analyses presented in the current paper are complementary to those reported in melgosa et al., 2017. from most currently available experimental datasets, our analyses do not allow a successful alternative proposal to the sl function proposed by ∆e00, because in most cases the improvements achieved by the candidate formulas are not statistically significant. in particular, our results show that replacing the sl function proposed in ∆e00 by sl=1, as done by cielab and cie94 (cie, 2004), and also recently suggested by berns (berns, 2016), is not a good choice. however, the replacement of cielab lightness l* by another lightness function, shown by the eqs. 4 and 5, based on whittle formula (whittle, 1992), leads to promising results. figures 1 and 2 also indicate that the sl function proposed by ∆e00 is not a satisfactory definitive result. however, it must be added that ∆e00 was recommended for a specific set of viewing conditions, the socalled ‘reference conditions’ (iso/cie, 2014; cie, 2001; luo, cui and rigg, 2001), which are not identical to those employed in all the visual datasets considered in the current paper (table 1). we hope that advances on new color spaces, in particular those with physiological basis, as well as a sounder knowledge of the influence of specific viewing conditions (parametric factors) on perceived color differences will lead to future color-difference formulas with improved performance. table 6 number of datasets or subsets with different kind of differences (columns 3-6) between several ciede2000-modified colordifference formulas (see text) and the original ∆e00 color-difference formula. 65 cultura e scienza del colore color culture and science | 10 | 2018 | 59 65 is it possible to improve the weighting function for lightness in the ciede2000 color-difference formula? issn 2384-9568 conflicts of interest the authors declare no conflict of interest affecting the results reported in this paper. funding this work was supported by ministry of economy and competitiveness of the government of spain, research projects fis2013-40661-p and fis2016-80983-p, with support from european regional development fund (erdf). bibliography berns, r. s., alman, d. h., reniff, l., snyder, g. d. and balonon-rosen, m. r. 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(1999). ‘geometric relations between scales of small colour differences’. color research and application 24 (2), pp. 78-92. https://doi.org/10.1002/(sici)15206378(199904)24:2<78::aid-col3>3.0.co;2-m cultura e scienza del colore color culture and science 4904/15 | cultura e scienza del colore color culture and science are lit by different illuminants. in the framework of digital imaging and computer vision, the illuminant estimation and correction is also referred to as white balance or computational color constancy. the second stage of the color correction pipeline transforms the image data into a standard color space. this transformation, usually called color space transformation or color matrixing, is needed because the spectral sensitivity functions of the sensor color channels rarely match those of the desired output color space. this transformation is usually performed by using a linear transformation matrix. many illuminant estimation solutions have been proposed in the last few years, although it is known that the problem addressed is actually ill-posed as its solution lacks uniqueness and 1. introduction there are mainly two modules responsible for the color rendering accuracy in a digital camera: the former is the illuminant estimation and correction module, the latter is the color matrix transformation. these two modules together form what may be called the color correction pipeline, or color engine. a simplified processing pipeline of a typical digital camera is reported in fig. 1, where the color engine is highlighted. the first stage of the color correction pipeline aims to render the acquired image as it was acquired under a known canonical illuminant. this is inspired by the color constancy feature of the human visual system (hvs), i.e. the ability of perceiving relatively constant colors when objects 1simone bianco simone.bianco@disco.unimib.it 1raimondo schettini schettini@disco.unimib.it 1disco dipartimento di informatica, sistemistica e comunicazione università degli studi di milano-bicocca adaptive illuminant estimation and correction for digital photography abstract in this paper we briefly review our recent research on classification-based color constancy, where automatically extracted features are used to drive the selection and combination of the best algorithm(s) for each image we also describe how the problem of illuminant estimation and correction is deeply intertwined with the one of color space transformation. finally, we also highlight research trends in these fields. figure 1 – simplified processing pipeline of a typical digital camera 50 cultura e scienza del colore color culture and science | 04/15 stability. to cope with this problem, different solutions usually exploit some assumptions about the statistical properties of the expected illuminants and/or of the object reflectances in the scene. in this paper we briefly review state of the art methods and our recent research on classification-based color constancy, where automatically extracted features are used to drive the selection and combination of the best algorithm(s) for each image. then, we describe how the problem of illuminant estimation and correction is deeply intertwined with the one of color space transformation. and, finally, we highlight research trends in these fields. 2. review of computational color constancy algorithms computational color constancy is the process of removing unrealistic color casts from digital images, mostly due to the acquisition conditions. from a computational perspective, computational color constancy is a two-stage process: the illuminant is estimated, and the image colors are then corrected on the basis of this estimate. the correction generates a new image of the scene as if it were taken under a known, canonical illuminant (see for example fig. 2). a generic image acquired by a digital camera is mainly characterized by three physical factors: the illuminant spectral power distribution i(λ), the surface spectral reflectance s(λ) and the spectral sensitivities c(λ) of the sensor. using this notation, the sensor responses at the spatial point with coordinates (x,y) can be then described as: where w is the wavelength range of the visible spectrum, ρ and c(λ) are three-component vectors. since the three spectral sensitivities of the sensor c(λ) are usually respectively more sensitive to low, medium and high wavelengths, the three-component vector of the sensor response ρ = (ρ 1 ,ρ 2 ,ρ 3 ) is also referred to as the sensor or camera raw rgb = (r,g,b) triplet (see for example fig. 3). assuming that the color i of the illuminant in the scene observed by the camera only depends on the illuminant spectral power distribution i(λ) and on the spectral sensitivities c(λ) of the sensor, the computational color constancy problem is equivalent to the estimation of i by: given only the sensor responses ρ(x,y) across the image. this is an under-determined problem and therefore cannot be solved without further assumptions and/or knowledge, such as some information about the camera being used, and/ or assumptions about the statistical properties of the expected illuminants and surface reflectances. the estimation of the color of the illuminant could be performed if an achromatic patch is present in the image. this is because the spectral reflectance s(λ) of an achromatic figure 2 – the two stages of the automatic white balance: the illuminant is estimated, and the image colors are then corrected on the basis of this estimate. the correction generates a new image of the scene as if it were taken under a known, canonical illuminant figure 3 image formation process ∫= w λλλλ d)(),,()(),( cñ yxsiyxρ ∫= w λλλ d)()( ci i 5104/15 | cultura e scienza del colore color culture and science surface is approximately constant over a wide range of wavelengths, and thus the sensor response ρ is proportional to i, i.e. the rgb of the achromatic patch is proportional to that of the incident light. to reduce the dimensionality of the problem, one common method is to not estimate the whole triplet of the illuminant color, but a 2d projection of it in a chromaticity space. in fact, it is more important to estimate the chromatic components of the scene than its overall intensity. the color correction is usually based on a diagonal model of illumination change derived from the von kries hypothesis. this model assumes that two acquisitions of the same scene with the same imaging device but under different illuminants are related by an independent gain regulation of the three imaging channels [1][2]. a diagonal model is generally a good approximation of change in illumination, as shown by finlayson et al.[2]. the colors in a scene, acquired under an unknown illuminant u can be transformed as they were taken under the chosen canonical illuminant by: where rgb = (r,g,b) is a color in the image acquired under the unknown illuminant, rgb' = (r',g',b') is the color in the corrected image, rgbu = (ru,gu,bu) are the sensor responses of a camera to a reference white under the unknown illuminant and rgbc = (rc,gc,bc) are the corresponding responses under the canonical illuminant. supposing rgbc is known, to obtain the color correction matrix, we have to estimate the illuminant color rgbu. to this aim several algorithms exist in literature, each with different assumptions [3]-[11]. to improve the illuminant estimation, schaefer et al. [12] introduced a combined physical and statistical color constancy algorithm that integrates the statistics-based color by correlation method with a physics-based technique, based on the dichromatic reflectance model, using a weighted combination of their likelihoods for a given illumination set and taking the maximum likelihood entry. cardei and funt [13] obtained good illuminant estimation by combining the results of gray world, white                     =           b g r bb gg rr b g r uc uc uc / / / ' ' ' patch and neural net methods, considering both linear and non-linear committee methods. we have investigated the idea of not relying on a single illuminant estimation method, but instead of considering a consensus decision that takes into account the compendium of the responses of several algorithms. to overcome the limitation deriving from the estimation of the illuminant color using the response of a single algorithm, methods that rely on the consensus of a set of different algorithms have been proposed [13] [14]. the underlying idea is that algorithms that give similar illuminant color estimations have to be trusted more than algorithms that give estimates that are far from the others, and thus the latter ones have to be automatically discarded. a different kind of algorithms proposed in the last few years belongs to the class of classification-based color constancy. the key idea is to exploit automatically extracted information about the content of the images and intrinsic, low level properties of the images. 3. classification-based color constancy we have in the last years proposed three different strategies of color constancy algorithm selection: a class-based (cb) [15] and a featurebased (fb) [16], and face-based (fcb) approach [17]. 3.1 class-based color constancy the class-based (cb) algorithm adopts a classification step to assign each image to either the indoor or to the outdoor class (see fig. 4). the classifier is trained on low level features automatically extracted from the images (see [15] for a detailed description). two different awb algorithms have been used for the two possible classes in which the image considered can be classified: on the basis of the classification result, only the corresponding awb algorithm selected has been applied. the algorithms for the indoor and for the outdoor class are selected from the one listed in [15], evaluating them on an independent training set. 3.2 feature-based color constancy the feature-based (fb) algorithm is based on five independent awb algorithms and a classification step that automatically selects which awb figure 4 – pipeline of the class-based color constancy 52 cultura e scienza del colore color culture and science | 04/15 figure 5 pipeline of the featurebased color constancy algorithm to use for each image (see fig. 5). the classifier is trained on low level features automatically extracted from the images (see [16] for a detailed description). the features on which the classification-based color constancy methods rely for the image representation can be divided into two groups: general purpose and specifically designed features. the use of low level features for the automatic selection and combination of the best color constancy algorithm (or combination of multiple algorithms) permitted to outperform existing state of the art algorithms on a widely used benchmark dataset [15],[16]. the class-based and the feature-based color constancy algorithms can be thought as exploiting respectively high-level and low-level features: the cb works on the output of a scene classifier, more precisely an indoor/outdoor classifier; the fb works directly on the low-level features extracted from the image. the use of medium-level features has also been investigated [18][19]: they are used in region-based color constancy algorithms which are able to automatically select (and/or blend) among different color corrections, including a conservative do nothing strategy. a new class of feature-based algorithms replaces the use of hand-crafted features with an endto-end learning of features and classifiers using convolutional neural networks (cnns) [37]. 3.3 face-based color constancy memory colors could be used as hints to give a more accurate estimate of the illuminant color in the scene. for example, moreno et al. [20] obtained memory colors for three different objects (grass, snow and sky) using psychophysical experiments. they then used a supervised image segmentation method to detect memory color objects and exploit them to color correct the image using a weighted von kries formula. a different approach has been used in [17] where a face detector was used to find faces in the scene, and the corresponding skin colors were used to estimate the chromaticity of the illuminant. the method was based on two observations: first, skin colors tend to form a cluster in the color space, making it a cue to estimate the illuminant in the scene; second, many photographic images are portraits or contain people. an extension of this idea could be to use “memory objects” in the scene for color constancy. if we are able to automatically recognize objects and logos that have intrinsic colors, we can use them for color constancy. the performances of the proposed color constancy algorithms are very good and they are fully detailed in [14]-[17]. the performance measure adopted is the median angular error between the estimated and measured illuminant. the datasets used are standard and widely for benchmarking algorithms as they are with ground truth illuminant measurements [32]. 3.4 adaptive face-based color constancy the face-based color constancy algorithm described in the next subsection has been extended in different ways [33]. since one of the assumptions that is often violated in color constancy is the presence of a uniform illumination in the scene, we have extended the applicability of the face-based algorithm to the case of non-uniform illumination. the method is adaptive, being able to distinguish and process in different ways images of scenes taken under a uniform and those acquired under nonuniform illumination. this was the first algorithm which automatically modifies its behavior from global to local color correction according to the analysis of the image content. furthermore, we designed a more efficient algorithm to estimate the scene illuminant from extracted skin regions using only their mean color value instead of the whole gamut. this algorithm is more suitable for resource-limited camera devices, such as consumer digital cameras and camera phones. 4. color space transformation the second stage of the color correction pipeline is the device chromatic response characterization and transforms the image data into a standard rgb color space (e.g. srgb, itu-r bt.709). this transformation, usually called color matrixing, is needed because the spectral sensitivity functions of the sensor color 5304/15 | cultura e scienza del colore color culture and science channels rarely match those of the desired output color space. typically this transformation is a 3-by-3 matrix with 9 variables to be optimally determined, and both algebraic [21] and optimization-based methods [22] exist to find it. the typical color correction pipeline can be thus described as follows: where rgb in are the camera raw rgb values, a is an exposure compensation common gain, the diagonal matrix diag(r awb ,g awb ,b awb ) is the channel-independent gain compensation of the illuminant, the full 3-by-3 matrix a (i,j) ,(i,j) = {1,2,3}2 = {1,2,3}g{1,2,3} is the color space conversion transform from the devicedependent rgb to the srgb color space, γ is the gamma correction defined for the srgb color space (where for abuse of notation it is intended to be applied component-wise), and rgb out are the output srgb values. usually the color matrix transform is optimized for a single illuminant and is applied as it is for all the illuminants that can occur. this could lead to high colorimetric accuracy if the occurring illuminant is the one for which the matrix has been derived (assuming that it is correctly compensated by the awb module), and low colorimetric accuracy for different illuminants. in [23] we have shown how to compute a combined matrix for different classes of commonly occurring illuminants. if only a-priori probability distribution about the illuminant occurrences is known, the best color matrix can be found offline and applied as it is for all the shots; if the awb is able to give a probability distribution about the illuminant in the scene (as color-by-correlation [9] does), an adaptive optimal matrix transform could be found for each shot. starting from the observation that the illuminant estimation is not error free and being an ill-posed problem [14] a perfect algorithm does not exist, color correction matrices, in addition to color space conversion, can incorporate information about the illuminant estimation process in order to compensate for its possible errors [23],[34] (see for example fig. 6). 4.1 adaptive color space transformation in [35] we designed and tested extended color correction pipelines for digital cameras able to obtain a higher color rendering accuracy. the pipelines proposed in [23],[34] have been further improved in two ways: i) in the illuminant estimation and correction stage, the traditional diagonal model of illuminant change has been replaced by a generalized diagonal transform found by optimization; ii) the color matrixing stage, usually performed using a linear transformation matrix optimized assuming that the illuminant in the scene has been successfully estimated and compensated for, has been extended exploiting polynomial color space conversions incorporating knowledge about illuminant estimation module behavior. [35] 5. conclusions and future works both the illuminant estimation process and the color correction matrix concur in the formation of the overall perceived image quality. we have briefly summarized our research activities concerning them. interested readers may refer to the cited works to have a detailed description of the algorithms as well as an exhaustive comparison of experimental results with respect to other algorithms in the state-ofart. independently from the merits of the single algorithms, we would like to point it out that illuminant estimation and color correction have figure 6 computation of color correction matrices which, in addition to color space conversion can incorporate information about the illuminant estimation process in order to compensate for its possible errors 54 cultura e scienza del colore color culture and science | 04/15 been always studied and optimized separately, thus ignoring the interactions between them. our works, to the best of our knowledge, are the first ones that have investigated their interactions and how to optimize them for the overall color accuracy. one of the possible further extension of these works regards the illuminant correction step. once the scene illuminant has been estimated the scene is usually corrected in the rgb device dependent color space using the diagonal von kries model [2]. several studies have investigated the use of different color spaces for the illuminant correction [24],[25],[26] as well as non-diagonal models [26]. a different approach could be to use chromatic adaptation transforms (cats) [27] to correct the scene illuminant. cats are used in color science and color imaging to model illumination change given the source and target illuminants. since in computational color constancy the source illuminant is unknown, the development of more accurate color constancy algorithms will allow to use more performing cats [28]. a different strategy for improving the reliability of color constancy algorithms is to increase the quantity of information available for the color constancy by taking two pictures of each scene [29]: the first is taken as normal, while a specially chosen colored filter is placed in front of the camera when capturing the second image. the filter is chosen so that the combined image makes color constancy, or white point estimation easier to solve. the availability of more color information available could be also used to increase the colorimetric accuracy of the device [30] or even for a spectral reconstruction of the scene [31]. the recent development of 3d cameras will surely boost these approaches. bibliography [1] m. d. fairchild, color appearance models, addison wesley, boston, mass. 1997. 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[37] s. bianco, c. cusano, r. schettini, “color constancy using cnns”, ieee computer vision and pattern recognition workshops (cvprw), 2015. 7 color culture and science journal vol. 11 (2) doi: 10.23738/ccsj.110201 the colored chemistry david ajò1,2, giuseppe elettivo3, federica fenzi1,4, stella nunziante cesaro1,5, sabrina tegani1,6 1smatch italia, rome, italy, smatchitalia@libero.it, ajod@libero.it, stella.nunziante@libero.it 2fondazione di storia onlus, vicenza, italy 3sole proprietorship ge stones, rose (cs), italy, giuseppe@giuseppeelettivo.it 4accademia di belle arti, verona, italy, federica.fenzi@accademiabelleartiverona.it 5ismn-cnr, c/o dip.chimica, università “sapienza”, rome, italy 6sole proprietorship rialto, fonte (tv), italy corresponding author: david ajò1,2 (ajod@libero.it) abstract we discuss here materials used in the fabrication of works of art and handicrafts, among them pigments and dyes, gemstones and jewels. attention is paid to their natural or synthetic origin and possible treatments. methods of characterization are important not only for historical and restoration purposes and the reproduction of ancient processes, but also for the purposes of new productions. in particular, in the fields of the effective microorganisms and metal surfaces coloration, some goals have been reached in this direction due to convergence of different education and research experience of the authors. keywords chemistry, restoration, gemology, colored metals, synthetic materials, treated materials, effective microorganisms received 30 march 2019; revised 10 june 2019; accepted 30 july 2019 the colored chemistry 8 color culture and science journal vol. 11 (2) doi: 10.23738/ccsj.110201 1. introduction the cultural association smatch (scientific methodologies applied to cultural heritage) has been created with the purpose of understanding cultural heritage and critically study methods adopted to know and protect it. a science which was always engaged in the sector of "beautiful" is chemistry: in this field we do not make separations between synthetic and analytical chemistry, nor between organic and inorganic: distinction born from a prejudice denied since the indigo industrial synthesis (marketed by basf, 1897). the material used for the "beautiful" (but the saffron is also used for the "good"…), such as gemstones or in general ornamental objects are made of natural raw materials, subjected, more often than people think, to chemical treatments. a special case is the diaspore (yellow gemological variety: zultanite) which shows (haüy 1801) how a heat treatment (even at not very high temperature) could unpredictably produce a synthesis. but intentional synthetic processes and treatments are now very common. we will describe in the present paper some of our research activities presenting cultural and productive interest. 2. pigments and dyes we cite here only a few cases, some of them regarding materials used as pigments in wall painting and not only. the synthesis modalities of such materials are investigated, among the others, for restoration: the advantage for a chemist in fact consists in the possibility of having, obviously not in all cases, items available to compare with the materials of the artifact. fig. 1. maya flower, jaina (méxico). photo courtesy of giacomo chiari. in europe, in the fabrics dyeing, both natural (in particular extracted from “indigofera tinctoria”) and synthetic indigo are employed. on the other hand, in the wall and other surfaces painting (figure 1), in pre-columbian times, but also later, we find the maya blue, a composite material (indigo-palygorskite clay) of exceptional stability. the knowledge of nature and history of this material (reyesvalerio 1993, chiari et al. 1999, ajò et al. 2000, berke 2007, sánchez del rio et al. 2011) is mostly due to the chemist (but also art historian and microbiologist!), constantino reyes-valerio. an ancient case of treatment is that of the odontolite, imitation of turquoise, obtained from fossil tusks of mastodon (reiche et al. 2000) by modification of the oxidation state of manganese. fig. 2. sumerian seal. the lapis lazuli is very precious because (according to the gemological criteria) "beautiful, rare and durable". on the other hand, sumerians produced seals (figure 2) able of transferring with their own mark the magical properties of the stone (ajò et al. 1996). since then it was used in jewelry production and as precious pigment to paint the sky, the madonna mantle and little else (aula et al. 1997): as a matter of fact, since ancient times the use of beautiful materials, for personal or collective purposes, can have spiritual implications. the production of synthetic ultramarine (analogous of lapis lazuli) was known more than two centuries ago (plester 1966, berke 2007). the colored chemistry 9 color culture and science journal vol. 11 (2) doi: 10.23738/ccsj.110201 egyptian blue, a synthetic silicate of calcium and copper (pozza et al. 2000, berke 2007, dyer and sotiropoulou 2017) was used in ancient times in egypt and later also in italy (colosi and prestileo 2017, bonifazi et al. 2017) in order to imitate copper minerals such as turquoise or azurite: the latter one, in particular, was subject to alterations in the wall paintings. its production dates back to the i dynasty (about 3100 b.c.) and originates from the pre-dynastic egyptian and asian culture. initially the blue glassy material (frit) was used as a glaze, and subsequently it was used also as a pigment (forbes 1955, riederer 1997). the later use became frequent or exclusive since the v dynasty (2494-2345 b.c.), for decoration of both organic and inorganic materials. in the egyptian middle kingdom (2133-1786 b.c.) a further extension in its use is witnessed, mainly for decoration of tombs in which wall paintings of exceptional extension were made. marcus vitruvius pollio (galiani, 1758) and pliny the elder (plinii secundi, 1873) inform us that the blue color (caeruleum), was introduced by vestorius in pozzuoli, in order to produce and sell it in italy. the more detailed roman sources is provided by vitruvius (first century b.c.), while pliny presents the diffusion of the alexandrian blue manufactured in pozzuoli: he makes indeed know that this color is labelled vestorianum blue. the production in the vestorius’ factory and the spread of his blue pigment were such as to influence the iii pompeian painting style, originated in the augustan period. in fact, from the year of caesar’s consulate (59 b.c.), the relationships with egypt became more intense and frequent until the age of claudius (41-54 a.d.). the use of this pigment characterized the 3rd pompeian style, in which an egyptian (vestorianum) blue produced in pozzuoli was widely used for making blue skies. fig. 3. powdered egyptian blue functionalized with em. we think it appropriate to introduce here the case of white lead, in which a chromatic alteration is frequently observed towards brown, imputable to an oxidative process due to microorganisms which colonize the wall paintings, producing lead dioxide (plattnerite) (petushkova and n.n.lyalokova 1986). these microorganisms are able to oxidize other pigments containing bivalent lead such as massicot and minium. furthermore, bacteria participate in the conversion of white lead to lead sulphide (black). these and several other evidences make it necessary the study and the experimentation, currently in progress, of antagonistic methods in order to restore and prevent the deterioration of wall paintings. actually, the antioxidant power of effective microorganisms is now recognized and used on a large variety of substrates and in various conditions (higa 1993, higa 2018). theirs reducing power is also exercised on metal ions. trials are underway on altered pigments, using products based on effective microorganisms (em): in particular, the egyptian blue has been recently reproduced by em-biotech (figure 3), not only for ornamental purposes but also as a material functionalized by the addition of beneficial microorganisms (em), for the coating of tanks and swimming pools. 3. precious materials for jewelry in 1902 (the same times of the indigo basf) auguste verneuil announced the synthesis of a ruby obtained by melting in the flame mixed oxide powders. in one of the laboratories of icis (cnr) in padua, an instrument was designed and used (figure 4) not very different from that of verneuil (maini et al. 2006). fig. 4. the verneuil apparatus of cnr in padua. the colored chemistry 10 color culture and science journal vol. 11 (2) doi: 10.23738/ccsj.110201 regardless of the commercial use (figure 5) of the obtained crystals, not always practicable, a chemist likes to make reference samples, to be compared with an unknown material: "this at least i know how it was done". fig. 5. synthetic sapphire of commercial interest. many methods can help the identification and the characterization of a synthetic or treated material starting from elementary analysis not destructive such as x-ray fluorescence (xrf). spectroscopic techniques, however, are always necessary. in any case, the study is more effective if the person performing the analyses (elementary, structural and spectroscopic) has also experience, at least in some case and to some extent, of syntheses and treatments. in this way it is possible to meet the needs of gemologists and jewelers (giarola et al. 2012). in fact, in the manufacture of jewelry, for imitation purposes instead of sapphires blue spinels (mixed aluminum and magnesium oxides) are used. practically, materials very often not existing in nature, are employed which share only a few properties with the imitated material, such as color and gloss, but differ for all remaining properties. a material different from the more valuable one but showing a similar appearance not necessarily represents imitation on the moral and juridical level. the "black prince's ruby"of the british crown is actually a red spinel: it is not about an intentional imitation, but an innocent misunderstanding, due to the absence of proper instrumentation. in this regard, it should be stressed that such precious objects are not removable, so it is good to have portable instruments, as the ftir interferometer used for study the marvelous diamond of vallerano (bedini et al. 2012), which could not leave ‘palazzo massimo alle terme” (rome). some colors of gems, in particular of brownish diamonds, are considered "ugly" (of negligible commercial value). this reason stimulated the study of methods suitable to change the characteristics of the stones (in particular the color). often a heat treatment is carried out in order to improve the color of a gem; but a heating procedure can be also effected for diagnostic purpose, producing desirably reversible phenomena; if instead we want to improve the color of a diamond for commercial purposes we desire irreversible changes. it can also happen that a gem, for the production (not reversible !) of “little flaws, which are singly unperceived" (shaw 1738) due to a thermal shock, loses apparently its color; but then it recovers it by means of an intentional treatment: in fact these cracks can favor the introduction of a dye, for example cochineal dissolved in alcohol (today we talk about "quench crackling"). we have to meditate on an interlacement of desired and non-desired phenomena. one of the most important issues of current gemology is the hpht (high temperature, high pressure) treatment of diamonds: high temperature (about 2000 °c), high pressure (about 60.000 atm), launched by general electric in 1999, capable of transforming brownish diamonds into gems substantially colorless (up to color d). in order to evaluate "a priori" the effectiveness of this kind of treatment, infrared spectroscopy is employed. in fact, the type i diamonds contain appreciable concentration of nitrogen which makes them less sensitive to physical treatment. on the contrary, this treatment is more effective for type iia diamonds whose coloration is predominantly associated with dislocations in the crystal lattice: this means that the concentration of nitrogen is negligible. therefore, ir spectroscopy helps to decide whether or not to apply the process, through an indirect reasoning that is worth reflecting on. we have already mentioned that a chemist, if he can, creates his own materials: in the case of diamond, treatment for color change is too drastic for an ordinary laboratory; on the other hand in another laboratory of icis, some crystal of brownish zoisite (of no commercial interest) were "cooked in foil" at 300°c and atmospheric pressure, obtaining a “pseudo tanzanite” having a pleasant, not natural, blue-violet color. an operation different from the hpht treatment, but with some points of contact on the logical and operational level, is the synthesis of the diamond. in 1970 a crystal of potential gemological interest has been produced by general electric, applying a hpht technique, in conditions distinct from those of treatments. catalysts or fluxes such the colored chemistry 11 color culture and science journal vol. 11 (2) doi: 10.23738/ccsj.110201 as metals were used, this procedure suggesting a possible clue to spectroscopists as well as, in some cases, to microscopists. diamonds produced by hpht have definitively canceled the distinction between organic and inorganic chemistry, since they were synthesized from biologic compounds such as the peanut butter, then from the "the loved one" by an alternative procedure to burial or ordinary cremation. more recently, diamonds have been presented by the apollo diamond of boston, exhibiting properties (including color and size) of gemological interest, obtained by the chemical vapor deposition (cvd) technique. this method is also used for coatings with thin and hard films, also useful for the protection of some artifacts. fig. 6. synthetic emerald “malossi”. some gemstones, such as emeralds (figure 6), unlike corundums (rubies and sapphires) and diamonds, can grow (from a "seed") at high temperature in aqueous solution by a so-called hydrothermal synthesis (adamo et al. 2005). what has been written up to now implies the knowledge of the structure of the materials, in particular of their defects and their impurities; for this purpose it has often been used, among the other techniques, photoluminescence spectroscopy not only for identification purposes but even more for the determination of the oxidation state and coordination of the chromophoric centers. a very instructive case, in which the distinction between synthetic and natural (same crystalline matrix, same chemical impurities) required the use of different spectroscopies, is that of blue sapphires. the guiding idea consists in the relatively easiness of reproducing in a laboratory the chemical composition of a sapphire (al203 with a small concentration of iron and titanium); a bit more difficult is the control of the oxidation state of iron: mainly bivalent in natural corundum (presumably born in oxygen deficiency), trivalent in some synthetics, probably grown up in the air. in general: two materials of the same composition, but born in different natural or laboratory contexts, may have some in common properties, in particular the color, and also density, hardness and refractive index. but they can have different properties as, in this case, the photoluminescence. the fact that, in cases like these, emission and absorption do not go hand in hand can be a problem for imitators but an advantage for gemologists and jewelers (and their customers). fig. 7. strongly oxidized glass. even in a sector at first sight "less noble", like that of industrial glass, a tight control of the oxidation state of the iron is fundamental: almost totally oxidized in the glass of figure 7. this was a subject, together with many others, of the collaboration between icis and the experimental glass station (murano, venice) (ajò et al. 1999). the colored chemistry 12 color culture and science journal vol. 11 (2) doi: 10.23738/ccsj.110201 finally, it may be considered that gems are often set in jewels (whose color effect depends on the combination of stones and metals, or of different gems): the prevalent use of yellow gold, in particular for diamonds, has been gradually overcome by the employment of platinum and white gold, not to mention rhodium-plated metals: yellow gold (or colored) remains the preferred in commerce especially for diamonds that show shades of yellow (for example with a relevant concentration of nitrogen). the combination of the color of the metal with the embedded gemstones is so important that in recent decades new techniques are used to obtain color variations of gold, no longer only due to the different alloys used, but also to the special rhodium treatment (galvanic process). the rhodium is not only used to make white gold bright and shiny but also to color it (in blue, in black, but the latter not very stable to physical stress). our present project is to use new metals which after particular treatments produce, by interference, effects till now unthinkable except if obtained through enamelling techniques. the best results so far were obtained with titanium. the study of new surface colors aims to the realization of elegant contrasts between metal and gems, or shades of tone on tone. besides, some metal colors can today be obtained with pvd (physical vapor deposition) but we are studying also techniques such as dlc (diamond-like carbon) coatings. 4. funding this research did not receive any specific grant from funding agencies in the public, commercial, or not-forprofit sectors. 5. conflict of interest this research holds no conflicts of interest. 6. acknowledgments we thank fernanda prestileo (institute for conservation and valorization of the cultural heritage of cnr, section of rome) for information and suggestions related to egyptian blue, and to giacomo chiari for sharing his experience during his activity as full professor (university of turin) and as chief scientist (getty conservation institute), as well as for the photo reported in figure 1. 7. short biography of the author(s) david ajò graduated in chemistry (university of rome) and graduate gemologist (gemological institute of america), worked on synthesis and spectroscopic investigations of materials used in works of art and handicraft, as research director of cnr (national research council, padua). fellow of “fondazione di storia” onlus (vicenza). contract professor at the università cattolica del s. cuore, seat of brescia, 20022011. stella nunziante cesaro graduated in physics and chemistry (university of rome), worked on high temperature systems at the research center ismn of cnr in rome. president of the cultural association “scientific methods applied to cultural heritage” (smatch), rome. collaborates with the department of classics at ‘sapienza’ (university of rome). giuseppe elettivo graduated in geology at the university of calabria (arcavacata di rende, cs), specialized in the mineral-petrographic field. independent gemologist, collaborated with icis of cnr (padua) within a project of the province of padua, and taught in the gemology school irigem (rosà, vi). expert in estimate and evaluation in jewelry and in the use of precious and non-precious metals. federica fenzi graduated in chemistry (university of padua) she carried out research at cnr (padua, 20012014), with archaeometric studies on glass, ceramics, bronze, pigments, hydraulic binders, and developing syntheses of eco-sustainable materials for industry and restoration. since 2013 contract professor of chemistry at the academy of fine arts (verona) and santa paola institute (mantua). sabrina tegani graduate gemologist (gemological institute of america), she learned gemstones cutting at irigem (rosà, vi), she worked in the gemological education certification institute (milan) as analyst gemologist and gemology educator. activity in antique and modern jewelry, among the others as rough diamonds analyst and consultant, recently started her business with her sole proprietorship "rialto". references adamo, i., pavese, a., prosperi, l., diella, v., merlini, m., gemmi, m. and ajò, d. (2005) “characterization of the new malossi hydrothermal synthetic emerald”, gems & gemology, 41(4), pp. 328-339. ajò, d., de zuane, f., caramazza, g., gambaro, m., guadagnino, e., morucchio, m., polato, p. and rizzo, g. (1999) "spectroscopic techniques for the determination of the iron redox state of glass and their direct application in the glass factory", glass technology, 40(4), pp. 116120. ajò, d., favaro, m. l., reyes-valerio, c., chiari, g. and giustetto, r. (2000) "characterization of maya blue by photoluminescence spectroscopy". xxxii internatonal symposium on archaeometry (méxico city). proceedings (british archaeological reports). cd-rom. the colored chemistry 13 color culture and science journal vol. 11 (2) doi: 10.23738/ccsj.110201 ajò, d., chiari, g., de zuane, f., favaro, m. l. and bertolin, m. 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(2007) “the invention of blue and purple pigments in ancient times”, chemical society reviews, 36(1), pp. 15-30. bonifazi, g., capobianco, g., paladini, a., prestileo, f., serranti, s., toschi, f. and trojsi, g. (2017) ”caratterizzazione degli intonaci dipinti. la caratterizzazione delle superfici dipinte”, in pensabene p. and sfameni c. (eds), la villa romana di cottanello. ricerche 2010-2016. bari: edipuglia, pp. 209-222. chiari, g., ajò, d., reyes-valerio, c. and de zuane, f. (1999) “application of photoluminescence spectroscopy to the investigation of materials used in works of art”, in proceedings of the 6th internat. conference on non destructive testing and microanalysis for the diagnostics and conservation of the cultural and environmental heritage (rome, 1999), aipnd and istituto centrale del restauro. rome: euroma, vol i, pp. 1717-1726. colosi f. and prestileo f. (2017) “censimento speditivo e analisi del degrado dei dipinti murali”, in pensabene, p. and sfameni, c. 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(2000) "photoluminescence of the inorganic pigments egyptian blue, han blue and han purple", journal of cultural heritage, 1(4), pp. 393-398. reiche, i. vignaud, c. and menu, m. (2000) “heat induced transformation of fossil mastodon ivory into turquoise ‘odontolite’. structural and elemental characterisation”. solid state sciencies, 2(6), pp. 625-636. reyes-valerio c. (1993) “de bonampak al templo mayor el azul maya en mesoamérica”. colección américa nuestra, vol. 40, américa antigua. méxico: siglo veintiuno editores. riederer j. (1997) “egyptian blue”, in west fitzhugh e., (ed.), “artists’ pigments. a handbook of their history and characteristics” (a national gallery of art u.s.a. publication), vol.iii, pp. 23-46. sánchez del río, m., domenéch, a. m., doménech-carbo, m. t., vázques de agredos pascual, m. l., suárez, m. and garcía-romero, e. (2011) “the maya blue pigment”, in galan, e. and singer, a. (eds) development in palygorskite-sepiolite research – a new outlook on these nanomaterials, chapter 18, pp. 453-481. elsevier. shaw, p. (1738) “the philosophical works of the honourable robert boyle”, vol.iii, p.105. london: printed for w. innys and r. manby, and t. longman. 25 color culture and science journal vol. 12 (1) doi: 10.23738/ccsj.120103 colour design of textile architectural envelopes: an initial study alessandro premier1 1 school of architecture and planning, creative arts and industries, the university of auckland, new zealand. alessandro.premier@auckland.ac.nz corresponding author: alessandro premier (alessandro.premier@auckland.ac.nz) abstract textile materials are now widely used in the construction of architectural envelopes. even if a wide range of colours is available today, only few of them seem to be preferred by the designers. a better understanding of this phenomena could be achieved through the study of the use of colour in relation to these architectural artefacts. in order to do so, the paper aims to show some of the interactions between the colour of textile architectural installations and some of the components that affect their design, in particular: form, function, lighting technologies and the context. the methodology of the research is based on a selected sample of buildings. these buildings have been investigated according to their surface colours and a set of other criteria. the results showed that white is the most widespread colour for this type of buildings. white seems to be strategic for enhancing complex and irregular forms and as a background for light projections, especially when the building needs to be highlighted in the context. multi-coloured surfaces seem to be preferred in temporary installations as well as in suburban or rural contexts. in general, the expected lifespan of these buildings and of their materials seems to be very important for the colour choice. this initial study is dedicated to architectural designers interested in the use of textile materials for the building envelope. keywords textile architecture, textile materials, colour design, architectural design received 08 october 2019; revised 25 november 2019; accepted 27 november 2019 colour design of textile architectural envelopes: an initial study 26 color culture and science journal vol. 12 (1) doi: 10.23738/ccsj.120103 1. introduction in the last decades textile materials, due to the evolution of textile composites, are more widely utilised in architectural applications (fritz 2011). current textile composites are used for the design of the whole building envelope, as well as for canopies, tensile structures, claddings and solar shading devices. the colour of architectural textile materials has always had an important role in different cultures (gasparini and zennaro 2007). without going too far back in time, in modern western society, we may say that high-tech textiles architectures (chilton 2010) are mainly characterized by whitish colours. even today, a simple google search with the keyword ‘textile architecture’ will produce a predominant number of whitish installations (fig. 1). however, since textiles are filters for the daylight, white is the colour that allows a good diffused light into the building (schock 2001). in the last years, like for many other types of architectural claddings (zennaro 2014), we have seen an increasing use of highly coloured architectural textile surfaces. these ‘new’ colours could be permanent (e.g. with high saturation) or temporary (e.g. light projected, light emitted), as for some types of textiles (ritter 2013). the choice of colour could be made according to the function of the textile object and other criteria (premier 2012). the investigation sought to better understand and discuss the use of colour in relation to some of the features of the architectural design of buildings, especially when colours other than white and grey are used. fig. 1. china corporate united pavilion of expo milano 2015 in italy, designed by the architectural design and research institute of tongji university ltd. a typical example of whitish textile surface. photo © alessandro premier. 2. research background textile materials are often used in temporary installations where colour is strategic for visual impact (fig. 2), but they are also used in claddings and shading devices with the same purposes (fig. 1, table 1). the colour is strongly influenced by the form of the object, that can be regular or irregular (trautz 2009). regular forms (based on primary solids or their combinations) or irregular forms (free-forms, parametric, hypersurfaces) (oosterhuis 2012) can produce different interactions with colour. a typical example is the chiaroscuro effect played by white or greyish volumes. another important aspect is the function of the object: building envelopes, claddings, solar shadings and canopies have all different needs when dealing with colour design, especially if we consider the intended use of the artefact. the functions of a textile envelope can be: cladding, shading and shelter (chilton 2010). surface texture quality can be an additional element of complexity. the colour of textiles can also be affected by the integration of lighting technologies. often, the object becomes a screen for night-light projections and this can be strongly related to the temporary nature of the object itself (e.g., designed for a specific event) or to the use of textiles as a screen (fig. 2). another important criterion is the chromatic relationship between the object and the surrounding environment. colour can be used to merge the object into the context or to highlight it. for instance, urban areas can be affected by saturated colours (fig. 3) as well as suburban areas, where the greyscale predominates (premier 2012). three different types of context have been identified: urban, suburban and rural (nguyen and teller 2016) and two different strategies have been associated to them: to blend or to highlight the building into the context. fig. 2. soundforms pavilion, olympic park, london, 2012. the white cladding becomes a surface for light projections. photo © nick guttridge (courtesy of es global ltd). colour design of textile architectural envelopes: an initial study 27 color culture and science journal vol. 12 (1) doi: 10.23738/ccsj.120103 fig. 3. selgascano pavilion, bruges, contemporary art and architecture triennial, 2018. a temporary installation with a ‘one colour’ envelope. design by lucía cano, josé selgas. photo © iwan baan (courtesy of selgascano). 3. objectives the aim of this paper is to discuss some of the interactions between the colour of textile architectural installations and some features of their design. in particular, the research is targeting the relationships between colour and form, function, temporary lighting technologies and context. this without neglecting other important criteria as location, lifespan and materials that will be the subjects of further investigations. this study could be useful for designers interested in the chromatic design of textile surfaces for architecture, to identify under what circumstances and with which modalities is possible to use certain colour strategies in order to obtain specific results. in particular, this study aims to question some of the reasons that may underlie the choice of colours or colour combinations that are different from the white or grey scale. 4. method the research is based on a sample of buildings built between the years 2000 and 2018. the information on these buildings was collected from 2009 to 2019 for a series of more than thirty articles developed for the italian magazines tenda in & out, and tenda international (tenda in & out 2018). a final limited selection of twentyeight textile architectures and shading skins has been identified according to the objectives of the research. the buildings have been studied according to their surface colour, the form of the building, the function of the textile material, the implementation of light projections and the colour strategy for the context. a comparison between the materials of the fibres’ coating has been added. the goal was to identify a set of relationships between the surface colour and the criteria shown in table 1, in order to better identify the colour strategies adopted for environmental design. b u il d in g s colour category whitish one colour multiple colours form regular irregular function cladding shading shelter fibres coating pvc ptfe gfrp pvdf other lifespan permanent temporary lighting technology yes no context urban suburban rural context strategy to merge to highlight table 1. the criteria of the research. the study of the surface colours was developed using the database of pictures provided by the designers of the case studies. the images were processed using adobe photoshop: rbg values were sampled and the colours were sorted using the closest ncs colour codes (arbab et al. 2018) (table 2). this process allowed us to identify three colour categories for these textile surfaces: whitish, one colour, multiple colours. building function colour category rgbs lighting context 1 chanel mobile art pavilion cladding whitish no urban 2 burnham pavilion cladding whitish yes urban 3 gardens by the bay shading whitish no urban 7 soundforms cladding whitish yes urban 8 zurich headquarte rs shading whitish no urban 1 1 outdoor room shelter whitish no suburba n 1 3 expo 2015 china ccup pavilion cladding whitish no suburba n 2 1 2018 bruges triennale pavilion shelter one colour no urban 2 2 le albere shading one colour no suburba n 2 3 ark nova shelter one colour no rural 2 8 cressy school shading multiple colours no suburba n table 2. buildings: excerpt from the synoptic table. colour design of textile architectural envelopes: an initial study 28 color culture and science journal vol. 12 (1) doi: 10.23738/ccsj.120103 the other criteria of the research were collected in a synoptic table and studied using a ms excel sheet. year and location of the buildings have been considered. a comparison between the identified colours and the other criteria has been carried out. the data have been collected in charts in order to study these relationships. 5. results and discussion as predicted, the majority of the case studies had whitish surfaces (from white to light grey). this is the most widespread colour range of textile membranes for architecture. there were seventeen case studies with a whitish coloured envelope. six case studies used a single colour surface (not in the greyscale) and a further five demonstrated the use of multi-coloured combinations. 5.1. colour and form the comparison between the three colour categories and the form of the buildings has shown that whitish surfaces seem to be the most frequent solution for complex and irregular forms. the chiaroscuro play of volumes and shapes is certainly enhanced by a ‘one colour’ surface, and above all, white. this is also connected to the wide use of whitish surfaces in modernist architecture (klinkhammer 2004). the combination of form and whitish surfaces is also related to the fact that these buildings maintain lower surface temperatures in hot climates, thus allowing better indoor performances. in regard to the location, twenty-one case studies were in europe, four in asia, two in the us and one in africa. wide literature is dedicated to the use of light/cool colours and coatings in warm climates (synnefa et al. 2007). the use of white, like the use of other colours, might be related to communication purposes. for instance, if we consider the ccup pavilion at milan 2015 expo (fig. 1), the choice of the whitish envelope might be related to the symbolic objective of the design. the pavilion was called ‘seeds of china’ and drawing on the symbolism of the seed, it interpreted the idea of a group of chinese companies that wanted to show their ‘values’ of conservation of natural resources and food security. the image of power that arises from the breaking of ground to the sprouting of seeds has inspired the design of form and colour of the ccup pavilion (wang 2015). 5.2. colour and function the study of the relationships between colour and function of the textile surface shows that, although whitish colours are the most widespread for all the three functions, there seems to be a strong preference for their use in claddings. in the cladding category there are no ‘one colour’ surfaces. in addition, the substantial balance of the three colour categories for the shading function seems to be relevant. in the design of shading devices, greyish and dark surfaces allow a higher performance of the combination window-shading device (carlo giovanardi & c. snc 2017). this could be a motivation behind the colour choices for the ‘shading’ function. three out of four case studies with ‘multiple colours’ surfaces had shading devices. an example of a façade with multi-coloured shading is the school centre in cressy (fig. 4). fig. 4. school centre in cressy (ch) (2002–2006) designed by dl-a (designlab-architecture). an example of a façade with multiple colours. photo © fausto pluchinotta (courtesy of serge ferrari). the building is characterized by a double skin glass façade that guarantees a rational management of the heat exchange between building and environment. the outer skin is configured as a structural glass cladding (spiderglass façade). the façade is coloured by the presence of vertical awnings installed in the cavity between the two skins. the façade is thus defined by the vertical bands marked by the different colours of the awnings. the fabric used is a soltis 92 by serge ferrari suitable for façade applications (serge ferrari sas 2012). the chromatic alternation of vertical bands plays a contrast between cold and warm colours: green, yellow, orange, light blue, beige (fig. 4). at night, the double skin lights up depending on the energy accumulated during the day. the light filtered by the coloured shading devices is reflected on the internal walls of the building, creating a complex play of colours (premier 2012). this is allowed by the function of the building (an early childhood centre) where colour has a strategic importance for learning (zennaro 2015). on the contrary: whitish surfaces allow a diffused daylight into the building and the light is not affected by any coloured filter. this use of whitish colours for shading is essential where high accuracy on colour rendering is needed. for instance, colour design of textile architectural envelopes: an initial study 29 color culture and science journal vol. 12 (1) doi: 10.23738/ccsj.120103 in museums (to appreciate paintings and other artworks), in libraries (to facilitate reading) and in offices (especially where people work with images). among the shelters there is a clear prevalence of ‘one colour’ solutions. examples of non-whitish ‘one-colour’ shelters are the water pavilion by selgascano (fig. 3) and the ark nova pavilion by arata isozaki and anish kapoor (fig. 5). fig. 5. lucerne festival ark nova. 2015 installation in fukushima. design by arata isozaki and anish kapoor. photo © yu terayama (courtesy of lucerne festival ark nova). 5.3. colour and lighting technology the comparison between the colours and the presence of lighting technologies shows that only whitish surfaces are used as screens for night-light projections (fig. 2). it is evident that a whitish colour, or a neutral light grey, is better suited as a screen for bright chromatic projections. in fact, with these technologies and with smart-textile technologies almost any colour is achievable and it is possible to use these colours only when it is needed (gasparini 2017). at certain times or in a specific place (e.g. if we talk about temporary architectures) it might not be appropriate to have a brightly coloured cladding and with these on-off technologies the problem is easily manageable. it goes without saying that highly saturated surfaces are not the best option for colour rendering in light projections. 5.4. colour and context the data regarding the context in which the buildings were located show that in urban areas, as city centres or historical centres, there are only ‘whitish’ and ‘one colour’ surfaces, while in the other contexts the other colour strategies are quite well distributed, even if there is a higher percentage of whitish surfaces. this data can be related to the fact that in city centres, ‘multiple colours’ surfaces are often not allowed for preservation reasons, while in other areas this is possible. an example of ‘one colour’ surface in an historical context is the water pavilion designed by selgascano (fig. 3). the water pavilion was built for the bruges 2018 triennale in belgium. launched in 2015, in its second edition (2018) it focused on the topic of the ‘liquid city’, with reference to the bruges watercourse network and according to the famous concept of liquid modernity (bauman 2000). the pavilion, located in the canal called coupure, was a temporary floating installation and served mainly as a platform for bathing and sunbathing. the installation consisted of a structure composed of steel bars covered with a fluorescent pink-orange vinyl membrane. the waterproof cladding was mounted on a floating wooden platform painted in yellow in order to stand out against the dark water of the canal (premier 2019). natural light passed through the skin of the pavilion creating a surprising and unsettling atmosphere that changed the usual perception of the old city. the structure had two irregularly shaped openings at the ends and curved around a void in the centre of the platform to form a tunnel through which visitors could move freely. the spanish architects josé selgas and lucía cano are mainly known for the 2015 serpentine pavilion in london (premier 2018). their work is characterized by the use of polymerderived materials and highly saturated colours. 5.5. context strategy the general result of the context strategy was a balance between the buildings designed to stand out from their context and buildings designed to merge into the context: fifteen buildings were considered ‘highlighted’, while thirteen buildings were considered ‘merged’ into their context. these results should be compared with the surface colour, the building form and the presence of lighting technologies. it was found that colour is not the only strategy used by designers to achieve one of the two objectives. for instance, amongst the whitish surfaces, ten buildings out of seventeen were designed to be highlighted in the context. this result was achieved mainly through unusual and irregular forms; an example being the chanel mobile art pavilion designed by zaha hadid. some of these buildings were highlighted in the context only by the use of lighting technologies: for example, is the envelope of the luanda multisports pavilion in angola with its sandy colour during the day and the coloured lights during the night (fig. 6). on the contrary, amongst the ‘one colour’ surfaces four out of six buildings were designed to merge into the context. this was achieved by the use of unsaturated or brownish colours. colour design of textile architectural envelopes: an initial study 30 color culture and science journal vol. 12 (1) doi: 10.23738/ccsj.120103 fig. 6. luanda multisports pavilion by berger arquitectos. photo © berger arquitectos. 5.6. coating and lifespan amongst the case studies, twenty buildings (71%) involved pvc coated textiles; only three involved ptfe coatings; individual case studies involved pte, pvdf, etfe, gfrp and aluminium mesh. the results did not show any evident relationship between the colour and the coating of the fibres. likewise, permanent and temporary buildings were equally distributed amongst the three colour categories. however, many considerations can be made on the use of these materials, their colour and the lifespan of the object. first, in permanent buildings greyish surfaces could be preferred because they show less stains and dirt, while white surfaces highlight the stains and dirt more. discoloration of pvc coatings is also a well-known issue (yousif and hasan 2015), thus white can be generally favourable also for this reason. another reason that could be related to the choice of whitish or greyish surfaces is the cost: higher request/quantity means lower prices according to economy of scale (azcarate 2014). thus, if white is the most utilised colour, this is likely also to happen in the future. pvc is the most frequent coating material. the pvc coated polyester fabric is a common material in tensile structures. its durability is guaranteed for ten years. it is presented in a wide variety of colours and is suitable for digital printing. texyloop® technology has been developed to recycle these types of fabric. (serge ferrari sas 2019). the pvc coating contains uv stabilizers against yellowing and fading, fireproof and anti-fungicide additives (serge ferrari sas 2017). 6. conclusions this project is a small part of a wider research endeavour, focussed on solar shading devices, started by the author twelve years ago. the limited number of twenty-eight selected buildings is due to the specific features necessary for the study: textile materials and additional functions (claddings and shelters). the number of buildings will be extended in the future to develop all the topics that emerged from this initial study. the goal of this study was to highlight and discuss some of the interactions between the colour of textile architectural installations and some features of their design. in particular, the research targeted the relationships between colour, form, function, lighting technologies and context. three colour categories were identified: whitish surfaces, ‘one colour’ surfaces and ‘multiple colours’ surfaces. the whitish surfaces were the most widespread for all types of applications: some considerations on the reasons for the choice of this color have been presented. the three colour categories were then compared with the other criteria of the research (table 1). some results are summarized below. colour and form. white seems to be more used for irregular forms: in those situations, form (not colour) is the main tool to highlight the building in the context. colour and function. there is a fairly regular distribution of the three colour categories for shadings. in shadings, multi-coloured solutions seem to be more frequent, but this strategy can be adopted only for some types of buildings. colour and lighting technologies. whitish surfaces are better suited to the integration with lighting technologies and light projections. in those situations, temporary colours are used to highlight the building, but only at night. the building might merge into the context during the day. colour and context strategy. multi-coloured surfaces seem to be not particularly common in urban centres, but they can be easily integrated in other contexts. colour and lifespan. in temporary buildings the colour choice can be adapted to a wider range of chromatic schemes. the lifespan of the material is also very important for the colour choice. generally, whitish and greyish colours are more durable than others. colour design of textile architectural envelopes: an initial study 31 color culture and science journal vol. 12 (1) doi: 10.23738/ccsj.120103 this paper voluntarily omits some aspects related to the history and culture of colour of textile materials presented by the author in other publications. further research can be carried out on the choice of colour in relation to the performances of these materials in specific climate zone. 7. conflict of interest declaration the author declares that he has no conflicts of interest. 8. funding source declaration the author received no specific funding for this work. 9. acknowledgment this research has been carried out using the material developed by the author in a number of articles for the magazines tenda in & out published by maggioli. i thank the designers and the companies cited in the article for providing drawings and technical data related to projects and materials. 10. short biography of the author alessandro premier architect, phd in technology of architecture, is senior lecturer in architectural technology and sustainable design at the school of architecture and planning of the university of auckland (nz). he carries out research and experimentations in the field of advanced technologies for the architectural envelope. references arbab, s., brindle, j. a., matusiak, b. s. and klöckner, c. a. 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(2015) il colore delle scuole. rimini: maggioli. 9 color culture and science journal vol. 12 (1) doi: 10.23738/ccsj.120101 three colour design proposals for the market square in warsaw karolina białobłocka1 1 independent researcher, wroclaw, poland. karolina.bialoblocka@gmail.com corresponding author: karolina białobłocka (karolina.bialoblocka@gmail.com) abstract research on the history and theory of colour planning in the built environment has been undertaken as the need to regulate colour and has become crucial as the proliferation of unlimited hues of artificial paints that, when applied without guidelines, may easily lead to visual chaos in the built environment. this particular study concentrates on colour planning for the market square in warsaw. the methodology employed included archival research and field studies. as a result, two colour design proposals from 1928 and 1951–53 were discovered, analysed and compared with the recently applied colour scheme supervised by the monument conservation board. this paper investigates how the colour design proposals were developed and applied, and finally, what atmosphere a coherent colour design proposal creates in a historic representative square. the results achieved also indicate that the analysed colour schemes provided a warm and welcoming atmosphere that was balanced with features of elegance and ceremony. additionally, the designs deepen the theoretical knowledge on colour planning and may help to establish guidelines on colour. keywords colour, colour planning, architecture, urban design, warsaw received 29 october 2019; revised 30 november 2019; accepted 17 december 2019 three colour design proposals for the market square in warsaw 10 color culture and science journal vol. 12 (1) doi: 10.23738/ccsj.120101 1. introduction a market square, usually a rectangular square surrounded by dwellings that house workshops on the ground floor with flats above, is a very characteristic feature of a central european city or town. rooted in the middle ages, a market square has been the centre of an average polish town for many centuries, and up to now, most of the market squares in poland kept their original, historical urban shape. over the centuries, however, façades have often been rebuilt in different architectural styles and colours have been adjusted to the new circumstances, accidentally or planned. in recent years, many attempts have been undertaken to refurbish polish market squares and research on colour planning for market squares has been conducted in search for how colour was treated and applied in those refurbishments. the colour design proposals discussed in this paper were examined in order to establish the ways colour has been organized in terms of composition within such an important urban area. in essence, this paper enquires into what role colour plays, what image colour helps to create, and finally, how colour contributes to physical ease and well-being of both inhabitants and visitors. so far, a few examples of colour planning for polish market squares have been presented in the literature. an attempt to coordinate colour in wroclaw was discussed in earlier studies (białobłocka 2017, białobłocka and urland 2019). the main ideas of a colour design proposal for płock were briefly analysed by romuald kozioł (1964). colour and historical preservation of cultural heritage was the subject of the conference ‘polychromies and sgraffito on the façades of old town centres rebuilt after 1945’ that took place in warsaw in 2015. in the conference proceedings, apart from discussing conservation issues, a few examples of colour planning were described such as selected issues related to colour design proposals for gdansk’s old town (kriegseisen 2015, kołodziej and brzuskiewicz 2015), warsaw’s old town (kania 2015), and lublin’s old town (żywiecki 2015). in this paper, the case study of warsaw is discussed (białobłocka 2019). two different colour design proposals for the market square are analysed from the point of view of the colour composition and further compared with the newly restored situation. 2. methodology the methods employed included archival research, interviews with people responsible for colour protection in warsaw, and field studies. archival materials included architectural designs and written sources such as comments in the press and building regulations. private communications with public officials took place in september 2010 and archival research and fieldwork were conducted in summer 2017. regarding archival materials, research was carried out in august 2017 in the following archives and museums in warsaw: archiwum akt dawnych, archiwum akt nowych, and in the archiv of the muzeum warszawy. archival material including designs from 1928 and 1951 were discovered in the museum of warsaw. furthermore, nine protocols on the polychrome restoration of 1953 were found in the archive archiwum akt dawnych. in regard to potential comments in the press, the main professional magazine on architecture of that period architektura did not include articles on colour design proposals for warsaw. general comments on the reconstruction of the old town after world war ii were published in daily local newspapers, e.g., trybuna ludu and stolica [7] (huml 1978). the examined building regulations did not include regulations on colour. the current colour scheme was discussed with the public officials from the warsaw monument conservation board in 2010. fieldwork that analysed recently applied colours was conducted in august 2017 under different daylight conditions, in the morning, midday and evening. the most important findings up to the present day include the discovery of two different colour schemes for warsaw’s market square. the initial idea was to gather together the data according to a questionnaire established for a research project in the attempt to analyse colour in the built environment. the questions on the form covered the sources of inspiration, the design methods, and the implementation of the colour plan. the findings, however, were limited; they provided data on the design principles but little information on the initiation and implementation of the colour design proposals. further examination of scattered sources is required to deepen the understanding of what inspired the colour concepts and how the colour plans were implemented. 3. colour planning for warsaw’s market square 3.1. the 1928 colour planning successful attempts to coordinate colour within the old town of warsaw (stare miasto) were made in 1928. initiated by the society for the preservation of historical monuments, a commission responsible for the polychromy scheme was appointed in 1928. three colour design proposals for the market square in warsaw 11 color culture and science journal vol. 12 (1) doi: 10.23738/ccsj.120101 fig. 1. the 1928 colour design proposal for all four sides of the market square, warsaw. source: muzeum warszawy, call number: mhw 15965-68. author unknown. photo: rafał chmielewski. three colour design proposals for the market square in warsaw 12 color culture and science journal vol. 12 (1) doi: 10.23738/ccsj.120101 bohdan urbanowicz (1911–1994), who was a painter, architect and professor at the academy of fine arts in warsaw, pinpointed an increasing degradation of the historic old town in the 1920s. the reasons he identified for the initiative of repainting the buildings surrounding the square on all four sides were the poor results of illegal works carried out by the house owners (urbanowicz 1953:143). at that time, in the 1920s, the properties were privately owned, yet, due to their historic value, the market square was listed in the building conservation inventory and, in fact, any work, including colour, had to be conducted in cooperation with the respective conservation units. the 1928 colour design proposal for the market square was honorarily created by a group of seventeen artists under the leadership of the well-known art deco painter zofia stryjeńska (1891–1976) (kania 2015:9). the art historian, critic and professor irena huml (1928–2015) also indicates that the group of artists contributed greatly to the renovation of the market square’s building façades as the artists not only conceived the colour design but also offered it to the city council (huml 1978:174). the commission accepted the design which was implemented in the same year (1928). the base of the 1928 colour design proposal was a sketch by zofia stryjeńska that indicated what colours the façades had to be painted and the artists of her team designed the details (kania 2015:11). regarding the composition of the colours, each side of the square is treated differently (fig. 1). named after jan dekert, the north side (strona dekerta), shows building façades painted alternately with two light colours, which are nuances of yellow and grey. apart from grey, the following colours are applied on darker architectural details: black, blue, brown, green and red. as a rule, one colour is applied to the wall surfaces, whereas two or three different colours are used on the details. ground floor levels are not differentiated from the upper levels. the chromatic lightness is a feature that differentiates this row of buildings from the other colourful rows [1]. named after hugo kołłątaj, the west side (strona kołłątaja) is characterized by strongly contrasting light and dark colours. unsaturated and highly saturated colours are applied in an irregular way. three façades are monochromatic, painted either blue or bluish grey; four façades are enriched with wall paintings; and three façades are covered with strong, contrasting colours, i.e., brown-orange and blue, yellow and blue, and peachy and blue [2]. named after ignacy zakrzewski, the south side (strona zakrzewskiego) is characterized by the use of various strong colours as each building is painted differently, either with light or dark colours. five façades are two-colour, two façades make the impression to be monochromatic, yet small surfaces are enriched with different colours, and one façade is covered with wall paintings [3]. named after franciszek barss, the east side (strona barssa), shows similar colourfulness as a main feature. the thirteen façades are painted green, bluish grey, orange, pink and yellow with no obvious rhythm. the architectural details are painted either a neighbouring shade of the hue applied to the façade surface or a contrasting hue. [4]. in regard to the colours used on the walls, two groups of colours dominate in this colour design proposal: ‘warm’ saturated yellows, oranges and peachy pinks co-exist with ‘cold’ light greys, beige-greys and bluish greys. greens are applied only on a few elevations (fig. 2). a characteristic feature of the 1928 design was its colourfulness, i.e., the use of vivid hues and contrasting colour compositions that was inspired by the expressionist art movement and folk art (kania 2015:9) the colour design described above was implemented using keim mineral colours and was officially presented to the nation on 11 november 1928, the 10th anniversary of the national independence day. in the press, the main complaint was the lack of colour harmony. a further criticism concerned the lack of reference to the original, historical colours. yet a torrent of harsh criticism received a new colour design in post-war years under different political circumstances (kania 2015:10, urbanowicz 1953:146). fig. 2. details of all the building façades above the ground floor level facing the market square from the 1928 colour design proposal. three colour design proposals for the market square in warsaw 13 color culture and science journal vol. 12 (1) doi: 10.23738/ccsj.120101 3.2. the 1951–53 colour planning new attempts to coordinate colours of the market square buildings took place 1951–53 in the post-war reconstruction of warsaw’s old town (stare miasto). colour planning was part of a much bigger reconstruction project of the polish capital that had been devastated in the 1944 warsaw uprising. the historic city centre was rebuilt and the gradual reconstruction was presented yearly to the nation on the 22 july, the national day of the rebirth of poland, which was introduced as a public holiday by the socialists in 1945 in replacement of the national independence day of 11 november. as in 1928, after the war, the area of the old town was listed in the conservation inventory and for this reason the development plans had to be approved by the monument conservation office. however, the ownership changed from private to public and due to the prevailing political system, all the designs had to be additionally approved by committees consisting of not only designers and public officials but also members of the party. in short, designs had to follow the rules of art recognized by the party. due to the official political doctrine, the old town was to be reconstructed as a residential area in an architectural style rooted in the polish tradition and embellished with social realism decor. as the official doctrine valued only gothic, renaissance and neoclassical architecture, it is not surprising that the pre-war polychromy created by art deco and modernist artists was not acceptable. in contrast to the 1928 proposal (perceived as not consistent, with too many bright colours with high saturation and underlining the independence of the artists), the new colour design was to be the result of a collective work: harmonious, with light colours and gilding sparkling in the sun. in the protocols, the term ‘pastel’ is often used to describe hues with high value and low saturation making feel the colours pale, soft and delicate. in accordance to the official political doctrine, the scheme aimed to create the atmosphere of a happy workers’ housing estate (zbiegieni 2015:49, kania 2015:17). the analysis of written sources does not provide information on the compulsory use of certain hues and shades. a uniform colour composition honouring historical colours was the aim, but it rather seems that the whole idea consisted of emphasising the success of socialist doctrine and had to differ from the previous colour design created under the capitalist system twenty-five years earlier. the final colour scheme, especially the range of hues applied and their degree of saturation was also a result of the limited availability of paints and their low quality. one of the first designs was made by the miastoprojekt group who presented a uniform colour design proposal kept in grey shades with tints, whereas the design by the wojciech jastrzębski team was kept in light colours commonly used in the 19th century (kania 2015:13–14, urbanowicz 1953:149). the 1951 design by pkz, pracownia architektury, consists of fifteen drawings for the old town including the north side (strona dekerta) [5]. according to the drawing, the façades should be either two-colour (six façades) or threecolour (two façades). the walls were to be painted one single hue and the architectural details a different hue, such as in five cases, in which the selected hues are expressed in terms of opposite sensations, i.e. a warm hue on the walls and a cool hue on the architectural details. the categorization of warm and cool colours, as recorded in the meeting minutes, is a way to describe hues with reference to their psychological effects on people rather than using colour attributes. the drawing was coloured using the aquarelle technique, and as such it provides the feeling of a somehow uniform, light colour composition. the rhythm is introduced by the alternate, but not consequent, use of warm and cold hues applied to the façades and the architectural details. in regard to the colour composition, the colours for the building façades are described on the drawing (from left to right): carmine red with grey ground floor; yellow; grey; green with gilding; pink with light yellow ground floor; greygreen with gilding; orange; and, bluish grey with gilding (fig. 3). fig. 3. the design preserved in the museum provides information on colours for the dekert’s side, which is indicated on the city plan below. author of the drawing: pkz pracownia architektury. source: muzeum warszawy. call number: mhw 130/pl. the team led by the painter jan sokołowski that based its concept on the previous greyish design by the three colour design proposals for the market square in warsaw 14 color culture and science journal vol. 12 (1) doi: 10.23738/ccsj.120101 miastoprojekt group, developed the idea of the so-called colour discretion and the horizontal sgraffito decorations. the realization of the design was supervised by the capital reconstruction office, directed by warsaw’s first chief architect józef sigalin (1909–1983). committee members included the main city conservator piotr biegański (1905– 1986), the general conservator jan zachwatowicz (1900– 1983), the chief designers jan sokołowski (1904–1953) and mieczysław kuźma (1907–1983) as well as the minister aleksander wolski (1913–1988) who represented the investor, this is, the state. the nine protocols dated from 29 april 1953 to 17 july 1953 communicate the discussions that concentrated on the improvement of the design proposal led by jan sokołowski, mainly on the façade colours applied and the amount of surface decorations [6]. several comments and suggestions were made during the meetings. for example, the meeting minutes of 29 april 1953 reveal that the preliminary idea of this design based on the use of intense colours (colours with high saturation) worried some committee members who found it too dark but expressed fears that the introduction of lighter colours could lead towards the destruction of sokołowski’s design idea, whereas others claimed that the design was too light, too ‘pastel’. it appeared that the 1:100 scale designs were too pale, whereas the detailed 1:20 scale designs were too colourful. in the end, it was decided that colours have to be better harmonized and elaborated decorations to be limited to a smaller number of façades [6]. the meeting minutes of 11 may 1953 reveal that the improved design treats the four sides of the market square in different and contrasting ways. painted dark greys and greens with gilded decorations and ornaments, the north side, or dekert’s side, was the most valuable and noteworthy. the east side, or barss’ side, was painted with warm hues complementing the greys. rich in architectural details, the south side, or zakrzewski’s side, was painted with light cool blues, whites and greens. and the west side, or kołłataj’s side, was characterized by shades of pink, red and purple. moreover, on each side a distinct accent colour enhanced the central façade of the building row by lightening colours with the addition of white. bohdan urbanowicz mentions that the whole colour scheme also was harmonized by applying dark brown to the window frames of all buildings (urbanowicz 1953: 151). during the other meetings, selected colours as well as sgraffito and fresco decorations were discussed on-site. colours and decorations were kept repainted in order to achieve a harmonized and discreet colour scheme that eventually satisfied the committee [6]. finally, in the early summer 1953, the improved colour design proposal was implemented using the technique of pigmented plaster, sgraffito and wet fresco. the completed reconstruction of the oldest part of warsaw was officially celebrated on 22 july 1953. in the press, the work was described as a positive achievement. the general monument conservator and architect jan zachwatowicz described the whole reconstruction of the old town as a step forward in building socialism. he explained that by incorporating the valuable past achievements of warsaw’s old town into the new, the socialist capital followed the development rules of socialist culture using the national culture in a creative way [7]. 3.3. current colours of warsaw’s market square, analysis of 2017 the currently applied colour scheme is not accidental but planned since the buildings in warsaw’s old town are listed by the warsaw monument conservation board. since 2 september 1980, it is a unesco world heritage site and as such the colours of the façades are supervised by the warsaw monument conservation office. for the reason that historical archive material is very limited due to the destruction of the city of warsaw during world war ii, based on a private conversation with public officials from the monument conservation board, we know that the monument conservation office utilised the colour design of the early 1950s as a basis for the refurbishment of the historic town. currently, the dekert’s side (north side, numbers 28–42) is a multi-coloured composition with one monochromatic and seven two-colour façades. the façades are of various hues with no visible rhythm: two shades of grey, creamy, brown and yellow, two shades of red, and two shades of green (fig. 4). the barss’ side (east side, numbers 2–26) provides a feeling of balance in terms of colours used. the façades are monochromatic and the use of colours is limited to warm hues discriminating the façades by introducing various shades of the same colour family. the zakrzewski’s side (south side, numbers 1–13) gives the impression of a uniform colour composition for two reasons. firstly, the façades are two-colour with the architectural details being painted lighter and warmer hues, and secondly, the colours are limited to warm shades. similarly, the kołłątaj’s side (west side, numbers 15–31) is perceived as a uniform colour composition. the row of buildings is covered with shades of warm hues, with the exception of two buildings painted grey. regarding the colours applied to the external walls, the range of warm red, maroon, yellow and brown dominates. cold hues such as grey-green, olive and blue are applied only on a few elevations (fig. 5). three colour design proposals for the market square in warsaw 15 color culture and science journal vol. 12 (1) doi: 10.23738/ccsj.120101 fig. 4. colours of the buildings of the four sides of warsaw’s market square as of august 2017. photos by the author. three colour design proposals for the market square in warsaw 16 color culture and science journal vol. 12 (1) doi: 10.23738/ccsj.120101 fig. 5. details of the façades above the ground floor of all the buildings facing the market square. photos by the author made in 2017. 4. conclusions archival research revealed the existence of two different colour design proposals from 1928 and 1951–53, and the current colour scheme was discussed with public officials. both colour design proposals were created as part of postwar reconstructions and aimed at commemorating the victory as well as emphasising the strength of the nation. yet, they were designed under different political circumstances that influenced the artistic creation. furthermore, both colour design proposals were conceived as complex colour schemes by groups of artists, whereas the currently applied colours are a result of paint investigation and archival research coordinated by the monument conservation board in warsaw. in all three cases, colours were designed for a protected area and for this reason they had to follow the conservation doctrines that generally aimed to reconstruct original forms. the designs had to be approved by public officials from conservation offices. however, the colour schemes differ: the 1928 one was the boldest in terms of the use of colour and also was influenced by contemporary art movements; the 1951–53 one aimed to emphasise the character of the buildings and honour the historical colours in the framework of the prevailing political doctrine; and, in current colour schemes, historical colours are valued most, but due to limited original material, the colours of the early 1950s are treated as a base for the restoration. in regard to the design principles, the comparative study of these two different colour design proposals and the currently applied colour scheme that is supervised by the local monument conservation board shows similarities and differences. the 1928 colour design proposal was characterized by multi-colourfulness and the application of saturated colours (strong, vivid colours) that are associated with gaiety and cheerfulness. judging by the available drawings and descriptions, the second attempt to coordinate colour made in 1951–53 provided a more balanced solution: still colourful in terms of hues, but limited in terms of lightness and saturation and balanced with grey that is associated with elegance and ceremony. and the current colour scheme as of 2017 is again dominated by warm colours that are associated with joviality, and partially balanced with grey that is associated with elegance. the colour designs discussed indicate that warm hues are widely used and in parallel with the application of grey. in this way, the feeling of cheerfulness is balanced by dignity and ceremony. regarding the comfort of passers-by, it was provided partially by the application of red and orange associated with enjoyment, but the feeling of tranquilly was limited as the use of blue and green was limited (fig. 6). fig. 6. the colours of the façades as of 1928 (design), 1951–-53 (design) and the current situation of 2017. three colour design proposals for the market square in warsaw 17 color culture and science journal vol. 12 (1) doi: 10.23738/ccsj.120101 5. conflict of interest declaration the author declares that she has no conflicts of interest. 6. funding source declaration the author received no specific funding for this work. 7. short biography of the author karolina białobłocka is an architect and researcher on theory and history of architecture. her research interests focus on the correlation between art and architecture, with special interest in colour. her previous research project concentrated on historical colour schemes of lower silesian architecture and current research focuses on guidelines on colour in urban planning. she obtained a doctoral degree from the wroclaw university of science and technology in 2015. notes [1] archival document, muzeum miasta warszawy, call number: mhw 15965 rynek starego miasta, strona północna /dekerta, after 1929, author unknown. [2] archival document, muzeum miasta warszawy, call number: mhw 15966 rynek starego miasta, strona zachodnia /kołłątaja, after 1929, author unknown. [3] archival document, muzeum miasta warszawy, call number: mhw 15967 rynek starego miasta, strona południowa /zakrzewskiego, after 1929, author unknown. [4] archival document, muzeum miasta warszawy, call number: mhw 15968 rynek starego miasta, strona wschodnia /barssa, after 1929, author unknown. [5] archival document, muzeum warszawy, call number: mhw 130/pl. [6] protocols of committee meetings related to the polychromy of warsaw’s old town preserved in archiwum akt dawnych in warsaw (call number: 771 /zespół 27 wydziału architektury zabytkowej biura odbudowy stolicy urzędu konserwatorskiego na m. st. warszawę z lat 1945–1953): ‘protokół kolegium opiniodawczego w sprawie odbudowy starego miasta zwołanego z inicjatywy konserwatora na m. st. warszawę w dniu 29.04.1953’; ‘protokół komisji do oceny projektów polichromii rynku starego miasta z dnia 11.05.1953’; ‘protokół kolegium w sprawie polichromii rynku starego miasta z dnia 15.05.1953’; ‘protokół posiedzenia kolegium opiniodawczego w sprawie polichromii rynku st. miasta z dnia 23.05.1953’; ‘protokół posiedzenia kolegium opiniodawczego w sprawie polichromii rynku starego miasta w warszawie z dnia 1.06.1953’; ‘protokół kolegium opiniodawczego w sprawie polichromii starego miasta z dnia 1.07.1953’; ‘protokół kolegium opiniodawczego w sprawie polichromii starego miasta z dnia 6.07.1953’; ‘protokół kolegium opiniodawczego w sprawie polichromii starego miasta z dnia 11.07.1953’; ‘protokół kolegium opiniodawczego w sprawie polichromii starego miasta z dnia 17.07.1953’. [7] historical articles in magazines and daily newspapers: zachwatowicz, j. ‘odbudowa starego miasta w warszawie’. trybuna ludu, nr. 202; 22 lipca 1953; gomulicki j. (1953) ‘trzy oblicza rynku staromiejskiego’, stolica, 30 (292); klinger k. (1953) ‘malarskie rozwiązanie rynku staromiejskiego’, stolica, 37 (299); kożmiński k. (1953) ‘polichromia rynku staromiejskiego warszawy’, dziś i jutro, 26; urbanowicz, b. (1953) ‘dwie polichromie starego rynku’, ochrona zabytków, 2–3, pp. 21–22. references białobłocka, k. (2017) ‘competitions for colour schemes for streets and squares in germany in the 1920s’. journal of the international colour association, 20, pp. 28–39. białobłocka, k. and urland, a. (2019) ‘does colour planning matter? reflection on the impact of colour coordination and planning in poland and slovakia’. architecture and urban planning. technical transactions, 6, pp. 17–36. białobłocka, k. (2019) ‘colour planning for the market square in warsaw’. proceedings of the first russian congress on color. schindler, v. m. and griber, y. a. (eds.) the scientific notes of the color society of russia, 1, smolensk: smolensk state university press, pp. 19–24. huml, i. (1978) polska sztuka stosowana xx wieku. warszawa: wydawnictwa artystyczne i filmowe. kania, j. (2015) ‘malowane dzieje. powojenne polichromie warszawskiego starego miasta: twórcy, dzieła i archiwalia’. polichromie i sgraffita na fasadach ośrodków staromiejskich odbudowanych po 1945 r. jagiellak, a. and świątek, p. (eds.) warszawa: biuro stołecznego konserwatora zabytków, pp. 9–30. kriegseisen, a. (2015) ‘w poszukiwaniu straconego koloru. wystrój barwny zachowanych i odbudowanych fasad głównego i starego miasta gdańska’. ibid, pp. 101–116. kołodziej, j. and brzuskiewicz, b. (2015) ‘kształtowanie tożsamości miejsca poprzez konserwację istniejących i wykonywanie nowych dekoracji artystycznych dla fasad kamienic odbudowywanych po 1945 roku na obszarze głównego miasta w gdańsku’. ibid, pp. 117–132. kozioł, r. (1964) ‘generalna koncepcja kolorystyczna płocka’. architektura, 6, pp. 253–254. wierzbicka, b. (1995) ‘polichromia rynku starego miasta w 1928 roku’. historyczne place warszawy. urbanistyka. architektura. problemy konserwatorskie. wierzbicka, b. (ed.) warszawa: towarzystwo opieki nad zabytkami, pp. 122–134. zbiegeni, a. (2015) ‘rastauracja elewacji frontowych kamienic strony dekreta na rynku starego miasta siedziby głównej muzeum warszawy’. polichromie i sgraffita na fasadach ośrodków staromiejskich odbudowanych po 1945 r. jagiellak, a. and świątek, p. (eds.) warszawa: biuro stołecznego konserwatora zabytków, pp. 43–58. zielińska-meissner u. (2011) ‘krajobraz warszawski, czyli o barwach dawnej warszawy’, krajobraz warszawski. magazyn urbanistyczno – architektoniczny, 127, pp. 1–12. żywiecki, j. (2015) ‘jak nowe stare miasto. polichromie i sgraffita z 1954 roku na elewacjach staromiejskich kamienic w lublinie’. polichromie i sgraffita na fasadach ośrodków staromiejskich odbudowanych po 1945 r. jagiellak, a. and świątek, p. (eds.) warszawa: biuro stołecznego konserwatora zabytków, pp. 147–166. 34 color culture and science journal vol. 11 (2) doi: 10.23738/ccsj.110204 chromatic values in pablo picasso’s early work: a comparison of hues in “science and charity” (1897) and its three oil sketches marcello picollo1, costanza cucci1, lorenzo stefani1, reyes jiménez-garnica2, laura fuster-lópez3, anna vila4 1 “nello carrara” institute of applied physics of the national research council (ifac-cnr), sesto fiorentino (fi), italy. m.picollo@ifac.cnr.it, c.cucci@ifac.cnr.it, l.stefani@ifac.cnr.it 2 museu picasso, barcelona, spain. rjimenezga@bcn.cat 3 universitat politècnica de valencia, instituto universitario de restauración del patrmonio, valencia, spain. laufuslo@crbc.upv.es 4 departament d’arts, conservació i restauració. universitat de barcelona, barcelona, spain. avila@ub.edu corresponding author: marcello picollo (m.picollo@ifac.cnr.it) abstract this paper deals with the chromatic and colorimetric analysis of one of the most representative paintings by pablo picasso (1881-1973) of his formative years, “science and charity” (ciencia y caridad, 1897), and its three oil sketches of the museu picasso in barcelona. picasso, among the modern painters, turned from a subdued chromatism to brilliantly varied palettes in the course of his career. measured colorimetric values obtained from reflectance spectra of relevant areas are presented and the evolution of the tones and hues used by picasso to enhance drama through the scenes represented in the four paintings selected is discussed. this study was carried out in the framework of an inter-institutional research project aimed to gain an insight into the failure mechanisms of modern and contemporary paintings. keywords pablo picasso, painting ciencia y caridad, conservators’ colour perception, fors, colorimetric measurements, hyperspectral imaging received 21 may 2019; revised 20 june 2019; accepted 05 september 2019 chromatic values in pablo picasso’s early work: a comparison of hues in “science and charity” (1897) and its three oil sketches 35 color culture and science journal vol. 11 (2) doi: 10.23738/ccsj.110204 1. introduction pablo picasso, who since the start of his career was supported by his father josé ruiz blasco, also a painter, obtained his first success in barcelona where his painting “science and charity” (ciencia y caridad, 1897, size 197.0 cm x 249.5 cm, inv. number mpb110.046) gained recognition also in a national competition. subsequently, the painting has been acknowledged as one of the most representative works of picasso’s formative years and it is one of his significant paintings belonging to the permanent collection of museu picasso in barcelona (mpb), where it has recently been restored. this oil painting on canvas depicting a bedridden woman reveals the artist’s early interest in fin-de-siècle art which was drawn to such topics as physical illness, madness, and decadence. it marks his accomplishment in academic art education in turn-of-thetwentieth-century spain. moreover, picasso was one of the modern painters who in the course of his career turned from a subdued chromatism to variegated palettes of brilliant hues (gage 2006). this paper will discuss one of his most important paintings hosted at mpb, namely, the already mentioned “science and charity”, and three smaller oil paintings on different supports (1896-97), all of which are displayed next to the big canvas and are considered to be its preparatory sketches. these sketches reveal a different organization of the scene presented in the larger version as well as differences in the hues the artist used in portraying the same characters and objects that appear in the scene. the present study was carried out in the framework of an inter-institutional research project (promesa) whose aim was to gain knowledge of the failure mechanisms of modern and contemporary paintings that produce degradation patterns in their paint layers (fuster-lopez et al. 2018). within the promesa project, the study of the materials and techniques used by the artist, in particular the chromatic and colorimetric analysis of picasso’s (1881-1973) paintings at the mpb, involved several different documentation and analytical methodologies. “colour,” as gage points out at the beginning of the introduction of his book “color in art”, “is implicated in physics, in chemistry, in physiology and psychology, as well as in language and philosophy; yet it is visual art alone that has engaged simultaneously with most or all of these branches of knowledge and experience …” (gage 2006). moreover, he continues, “colour is primarily a psychological phenomenon.” indeed, although the link between various colours as a psychological phenomenon and the way artists apply their creativity to experimenting with colour has already been explored by art historians, critics, and artists themselves (buswell 1935, arnheim 1974, gombrich 1968, gage 1999), the reflections expressed in their publications often do not stem from or take into consideration scientific data and measurements. hence, the present study proposes a relatively new method in gaining insight into artworks by merging the visual approach employed by professionals, such as painting conservators, who have expertise in the field, with scientific measurements of colorimetric values calculated from the reflectance spectra of the specific investigated spots (parraman 2010, striova et al. 2018, dooley et al. 2014). this study started with a visual investigation of the various colours the young picasso used in the four paintings to stylistically structure them; subsequently, ten spots (areas with a diameter of 3 mm) were selected on the same zones of each painting to be measured by using a spectrocolorimeter (figs. 1-4). the aim was to discover if there were any associations in the painted scenes – in the painting and the three oil sketches—between the measured colorimetric values, the chromatic painting balance, and the colour perception of mpb conservators so as to gain an enhanced understanding of the conditions of these artworks. fig. 1. painting “science and charity” (mpb 110046) with the investigated spots. 2. “science and charity” painting and its sketches at the end of 1896 and beginning of 1897, picasso worked on the painting “science and charity” (fig. 1). it was the most ambitious early work by the young artist (gual and jiménez 2010, jiménez 2018). the choice of the topic was not unintentional; the human condition and illness had intrigued him since the death of his sister conchita (who passed away in january 1895), but he was also fascinated by real life and social issues that he foregrounded in the scene. indeed, with this painting, picasso connected with chromatic values in pablo picasso’s early work: a comparison of hues in “science and charity” (1897) and its three oil sketches 36 color culture and science journal vol. 11 (2) doi: 10.23738/ccsj.110204 the social realism movement, whose popularity at the time was at its peak in all of europe. the origin of the socalled ‘hospital theme’ addressed in the painting can in spanish art be traced to 1889 when luis jiménez aranda won the gold medal at the spanish pavilion at the universal exhibition in paris with his painting “the doctor’s visit”; it was one among other artworks that depicted similar subjects. in may 1897, this large oil painting on canvas was exhibited at the 16th fine arts general exhibition in madrid, where it was also awarded. some months later, it was sent to málaga to the provincial exposition. the painting then remained in málaga at the house of picasso’s uncle, salvador ruiz. it was kept there until the uncle’s death in 1918, after which it was brought back to barcelona. since then, this impressive canvas was hanging in the picasso family house located in barcelona. it was only in may 1970 that the artist decided to donate it to the mpb so that it could be integrated into its permanent collection. during the same year, the painting was treated in the conservation studio of the museus de barcelona at the museu nacional d’art de catalunya (mnac) in barcelona. the conservation work included relining the fabric and mounting it on a new stretcher, retouching the paint losses, and varnishing the painting. since then, it has been displayed in the museum galleries. it was loaned out only in 1980, to participate in a picasso exhibition organized at the museum of modern art (moma) in new york. in addition to the early conservation work, scientific analyses were performed on “science and charity” for the first time in 2008. these included x-ray radiography, which assessed the condition of the original fabric and contributed to the study of the artist’s technique. in addition, several micro-samples were taken in order to determine the cross-section of the painting materials. the results of these scientific analysis were presented within the context of an exhibition entitled ciencia y caridad al descubierto and were subsequently published in the exhibition catalogue (gual and jiménez 2010, jiménez 2018). these were the first scientific studies that contributed to the understanding of the pictorial technique, while also enabling an enhanced documentation of picasso’s working process. for instance, the x-ray radiography revealed that the artist had worked in multiple sessions during which he made several modifications to the composition. in some areas of the painting, for example in the blanket covering the ailing woman, as many as seven successive colour applications were observed and, moreover, it was discovered that in most cases the subsequent paint layers had been applied only after the previous layer had completely dried. another significant discovery concerned the correspondences that now could be demonstrated between “science and charity” and other works of smaller format: six from mpb and other three belonging to other collectors. these small paintings, which until 2008 were thought to be preparatory sketches, were instead revealed to be key-documents that played an important role in the artist’s creative process during the execution of “science and charity”. they allowed not only the preparation of a chronological sequence (table 1), but also helped illustrate in a visual way the different phases of the painting process of “science and charity” since each of them represents a transition to the subsequent stage until the completion of the final version. thus, together the paintings form an invaluable documentary set. when compared to the final version, the noteworthy alterations in the smaller paintings, together with compositional changes and modifications concerning light and colour demonstrate the young artist’s efforts in ameliorating the narrative realism and pictorial composition of the painting. artwork technique place and date size (cm) mpb 110387 charcoal on paper barcelona, 1896 10.5 x 27.7 mpb 70802r charcoal and conté pencil on paper barcelona, 1896-97 28.0 x 47.5 mp 409(r) zervós xxi, sheet 46 [10] brown ink, watercolor enhancements and violet ink on paper barcelona, 1896 16.5 x 22.2 mpb 110099 oil on canvas barcelona, 1897 23.8 x 26.0 mpb 110089 watercolor on paper barcelona, 1897 22.5 x 28.6 mpb 110229 oil on panel barcelona, 1897, dated on the reverse march 1897 19.5 x 27.2 zervós, vi, sheet 46 [10] watercolor, ink and pencil on paper barcelona, 189697 37.0 x 25.5 mpb 110214 oil on panel barcelona, 1897 13.6 x 22.4 mpb 110046 oil on canvas barcelona, 1897 197.0 x 249.5 zervós, i sheet 10 [10] oil on canvas barcelona, 1897 38.0 x 48.0 tab. 1 artworks in the mpb collection related to the genesis of “science and charity” listed chronologically (in bold the work of arts investigated in the present study). 3. considerations about the investigated sketches the four oil paintings belonging to mpb (mpb 110046, 099, 214, and 229, see table 1) were studied within the promesa project so as to establish their different physicochemical correlations that would help to gain a chromatic values in pablo picasso’s early work: a comparison of hues in “science and charity” (1897) and its three oil sketches 37 color culture and science journal vol. 11 (2) doi: 10.23738/ccsj.110204 better understanding of the condition of the painting. in 2018, these four paintings were analysed by using the following spectroscopic techniques: visible (vis) and near infrared (nir) fibre optic reflectance spectroscopy (fors), in the 350-2200 nm range, on different spots on the painting surfaces; reflectance hyperspectral imaging (hsi) in the 400-900 nm (vnir) and 950-1650 nm (swir) ranges (hsi on the painting science and charity, mpb 110046, was acquired only in the swir region). furthermore, measurements focused on the colorimetric data on 10 selected spots were also recorded by using a konica-minolta cm700d spectrocolorimeter (konica minolta 2008). in addition, in 2010 a set of micro-samples taken only from the painting “science and charity” (mpb 110046) had already been analysed by using scanning electron microscope (sem) and fourier transform infrared (ft-ir) techniques. in this paper, however, it was decided to report the colorimetric data only. fig. 2. painting mpb 110099 with the investigated spots. the first small painting analysed was the mpb 110099 (fig. 2), which is a rapidly made sketch on a piece of cloth revealing certain clumsiness, which makes it probable that picasso abandoned it, also because it does not have any resemblance to the final version. the second preparatory oil painting mpb 110229 (fig. 3), which the artist dated on the verso of the panel (march 1897), presents a structure that appears more similar to the final version. here the nun, in the centre of the scene right next to the main characters, is standing close to the bed holding a cup in her right hand and a child on her left arm. in this version, the child is naked and looks younger than in the final painting. in addition, the sick woman here is not looking toward the doctor, and her right arm is placed on the bed, while the doctor is depicted holding her hand. the main character of the composition, the doctor, is here not seen in profile but portrayed in a three-quarter view like in the final big canvas painting. however, there is still a big difference between this and the final version: here, like in the first sketches, including the watercolour (mpb 110089), the doctor’s hair is white. in addition, the window is positioned on the right section of the scene. fig. 3. painting mpb 110229 with the investigated spots. this work maintains the luminosity of the previous version evident in the great brightness and palette that abounds in white, grey and ochre. the only dark colours, which persist throughout the execution process, are the black of the doctor's frock coat and dark blue of the nun’s dress. in this particular oil sketch, as discovered in an image extracted at 1300 nm (ir reflectography) from the swir hsi data, picasso made an attempt to seat the doctor in a rocking chair, whose skates he subsequently covered with light paint, turning the seat into a chair. this detail does not lead to picasso’s final version either because the final painting shows a rectilinear structure of the legs of the chair. in the painting mpb 110214 (fig. 4) the artist decided on a radical change that brought him closer to the final painting. he dressed the child in a red suit and rectified his position by placing him higher within the composition. in this way, the child is slightly separated from the mother and physically closer to the nun, who has also turned to a three-quarter position. the figure of the doctor is already resembling the physiognomy of picasso’s father, don josé. the figures in this sketch all have a certain disproportion to the general format of the board support, which seems to indicate that it is a sketch quickly prepared with the purpose of studying the chromatic and tonal effect without altering the basic composition. in this sketch, and by extension in this phase of the creative process, the palette changes completely. it seems that picasso gradually darkened the composition, throwing shadows over the scene: he seems to have decided to cover the white sheet with a rough ochre blanket, to apply a dark chromatic values in pablo picasso’s early work: a comparison of hues in “science and charity” (1897) and its three oil sketches 38 color culture and science journal vol. 11 (2) doi: 10.23738/ccsj.110204 brown coat on the light grey background around the doctor, and literally to close the window by masking the white appearing in the preparatory versions with a very thin brown coat. it seems that from this moment, the painting has obtained its final version, with the exception of the frame in the centre of the wall, which, however, appeared in the zervos version. this fact suggests that zervos is the last sketch picasso worked on before completing his final version of “science and charity” (zervos 2013). 4. colorimetric data the analytical results reveal that despite the dissimilarities in the structure and composition of the four oil paintings (including furniture, position of characters, etc.), the artist used similar painting materials (i.e. pigments) in all four versions. this knowledge facilitated the selection of ten spots on each artwork; these were the most representative hues and details apparent in the final painting. after careful consideration, it was decided to analyse the following spots (figs.1-4): 1) on the wall in the background in the centre of the scene; 2) the brownish window curtain/shutter; 3) the sick woman’s face; 4) the doctor’s face; 5) the nun’s face; 6) the white bed sheet; 7) the right sleeve of the doctor’s jacket; 8) the blanket or the sheet at the end of the bed; 9) the nun’s dress; 10) the child’s dress. since the child was missing from the scene of the first sketch (mpb 110099), spot n.10 was not included. measurements of the chromatic parameters were carried out with the spectrophotometer konica-minolta cm-700d model (fig. 5). this instrument measures reflectance spectra with an acquisition step of 10 nm in the 360-740 nm range. measurements were acquired using the geometry of diffuse lighting, angle of view of 8° with respect to the normal and exclusion of the specular component, using the 3 mm in diameter probe-head (konica minolta 2008). the colorimetric data reported in this work were calculated in the ciel*a*b* 1976 colour space for the 10-supplementary standard observer (1964) and daylight d65 illuminant (table 2) (wyszecki and stiles 1982, cie 1982, iso/cie 10526 and 10527 1991). fig. 4. painting mpb 110214 with the investigated spots. mpb 110099 mpb 110229 mpb 110214 mpb 110046 l* a* b* l* a* b* l* a* b* l* a* b* 1 40.5 1.0 1.2 39.4 -0.5 11.0 42.6 -0.4 4.3 39.6 -1.6 1.7 2 51.5 3.9 14.1 53.3 4.3 24.2 32.2 4.1 3.7 29.4 5.9 5.8 3 47.6 5.0 14.6 33.3 4.1 11.2 35.6 4.3 9.8 49.8 6.2 18.5 4 51.9 5.4 9.8 30.8 1.3 10.6 29.8 1.1 2.9 39.3 7.6 10.0 5 54.1 4.1 7.6 38.7 12.0 14.6 38.5 4.2 9.5 47.7 6.5 16.0 6 51.1 0.7 9.0 37.4 7.4 18.5 36.2 4.5 7.3 57.1 2.6 11.3 7 41.2 0.1 2.0 26.0 0.6 3.2 25.1 -0.4 -0.5 26.8 -0.3 -1.4 8 48.8 0.0 4.1 45.5 1.4 10.8 42.4 5.0 15.1 40.4 4.5 14.5 9 32.8 0.2 0.3 34.5 -2.9 0.5 27.0 0.0 0.0 25.6 -0.1 -1.2 10 33.2 12.1 12.2 34.6 11.2 10.3 46.5 3.6 9.1 tab. 2 l*a*b* (10°/d65) colour values of the investigated areas for the four oil paintings. chromatic values in pablo picasso’s early work: a comparison of hues in “science and charity” (1897) and its three oil sketches 39 color culture and science journal vol. 11 (2) doi: 10.23738/ccsj.110204 mpb 110229 mpb 110229 mpb 110214 l* a* b* δc* δl* δa* δb* δc* δl* δa* δb* δc* 1 0.9 2.6 -0.5 -0.8 -0.2 1.1 9.3 8.9 3 1.2 2.6 2.0 2 22.1 -2 8.3 6.4 23.9 -1.6 18.4 16.4 2.8 -1.8 -2.1 -2.7 3 -2.2 -1.2 -3.9 -4.1 -16.5 -2.1 -7.3 -7.7 -14.2 -1.9 -8.7 -8.8 4 12.6 -2.2 -0.2 -1.4 -8.5 -6.3 0.6 -1.9 -9.5 -6.5 -7.1 -9.5 5 6.4 -2.4 -8.4 -8.6 -9 5.5 -1.4 1.6 -9.2 -2.3 -6.5 -6.9 6 -6 -1.9 -2.3 -2.5 -19.7 4.8 7.2 8.3 -20.9 1.9 -4 -3.1 7 14.4 0.4 3.4 0.6 -0.8 0.9 4.6 1.8 -1.7 -0.1 0.9 -0.8 8 8.4 -4.5 -10.4 -11.1 5.1 -3.1 -3.7 -4.3 2 0.5 0.6 0.7 9 7.2 0.3 1.5 -0.8 8.9 -2.8 1.7 1.8 1.4 0.1 1.2 -1.1 10 -13.3 8.5 3.1 7.4 -11.9 7.6 1.2 5.5 tab. 3 – l*a*b* and c* (10°/d65) differences of the three sketches considering the final painting (mpb 110046) as reference. the ‘atmosphere’ of the scene is most strongly conveyed through the hue used to paint the walls of the room. the data obtained from the four paintings showed no noticeable discrepancies: an inhomogeneous mediumlight grey hue on the main wall that is more neutral (achromatic) for the first sketch and the final paintings than the other two intermediate sketches, which instead present a bluish predominance. fig. 5. acquisition of colour measurements on the science and charity painting, final version. the second spot, instead, shows a strong variation in hue passing from one sketch to the others and it turns into a saturated, dark brown in the final version. it is important to note, however, that the resulted colour is more neutral in the last two paintings, with a slight red and yellow presence, than in the first two sketches where the yellow tint is more dominant (fig. 6). the complexion in the faces of the three adult figures varies not only between the paintings but also within each painting. this seems to confirm the hypothesis that the first three paintings were preparatory sketches in which the artist found no necessity to refine the faces. moreover, picasso used the colour of each character’s complexion to indicate their healthy or sickly condition. the measurements confirmed that the sheet on the bed was whitish with some chromatic dominant turned into yellow. only in the third sketch the white results more neutral with almost the same values of both yellow and red contributions. fig. 6. l*a*b* (10°/d65) colour graph of the investigated 2nd spot for the four paintings: mpb 110046 (green), mpb 110099 (blue), mpb 110214 (red), and mpb 110229 (purple). the blanket on the bed is included in the scene only starting from the last sketch. however, the colorimetric values do not reveal any significant differences moving from the sketch to the last version, the final painting. in the first two works, the blanket blends in with the sheet, of a creamy hue, which, in the later versions, is not so different from the yellowish-brown final hue (fig. 7). chromatic values in pablo picasso’s early work: a comparison of hues in “science and charity” (1897) and its three oil sketches 40 color culture and science journal vol. 11 (2) doi: 10.23738/ccsj.110204 fig. 7. l*a*b* (10°/d65) colour graph of the investigated 8th spot for the four paintings: mpb 110046 (green), mpb 110099 (blue), mpb 110214 (red), and mpb 110229 (purple). the hue of the doctor’s bluish dark jacket remains more or less constant throughout the genesis of this artwork. the nun’s dress is almost black in all versions except in the second one in which it is depicted as a bluish dark tone. the final spot, the child, appears in three different situations: the naked child, a child with orange-red cloth, and finally a child wearing a reddish-lily shirt. however, the colorimetric parameters for the first two variations of the naked and clothed child are almost identical, which is due to the similar tones of the child’s complexion and his clothing. in the last version, the child’s dress presents diverse colorimetric values than the first two, as expected also simply by looking at the painting. 5. some final considerations and conclusions the results of this research demonstrate that although the differences in colour in the four different versions of the same scene could be perceived by naked eye, the spectrophotometric colour measurements provided clear and objective information about the early palette picasso used in introducing the emotional effects into the analysed paintings. hence, the colorimetric values obtained from reflectance spectra of relevant areas contribute to the understanding of the evolution in the tones and hues picasso employed to enhance the dramatic impact of the scene represented in the four paintings. from a psychological and artistic viewpoint, the natural scale of the characters in the final version of “science and charity” conveys a sense of veracity and transmits stronger emotional charge. however, it is through the evolution of the chromatic elaboration that picasso truly managed to accentuate the drama. for instance, the interplay between the clear and sombre architecture and the areas that remain in shade highlight the dramatic nature of the scene in which also the healthy characters are contrasted with the sick woman. every small detail and larger organisation of the elements, for example the doctor’s prominent presence in front of the patient’s emaciated face, contribute to the pathos and imminent fate. the pallor of the patient is accentuated plastically through the comparison with the white of the sheet but also by the skilful choice of pigments. although the artist tended to use lead whites (both pure and in the mixtures), here he decided to add zinc white to accentuate the sickness, now evident in the woman’s mortuary complexion. these two different white pigments were identified by means of fors and hsi techniques (bacci et al. 2007). the healthy-looking child, on the other hand, offers a positive view of the continuation of life. in one of the first versions his vulnerability is emphasised through his nakedness and the direction of his arms, as he reaches towards the sickly mother, but in the subsequent versions the drama has decreased: in the sketch mpb 110214 he is clothed, and in the final painting he not only wears a nice dress but also gathers his arms, thus remaining connected to the scene under the protection of the nun. throughout the painting process, the doctor is depicted as a figure of dignity; he wears a sober black frock coat that forms a contrast to the shining white collar and sleeves. in this way, picasso had completely transformed the initial intention of presenting a certain luminosity by placing the characters in a chiaroscuro framework that accentuates the drama of the event. this big canvas painting is remarkable in many ways; first of all, it was executed by a 15-year old artist during the formative years of his brilliant career. moreover, although some elements in the scene do not exactly correspond to reality (i.e. the technically well-executed cornucopia decorating the wall, which is a discordant element), the greatness of the artist’s achievement comes across through the painting’s pictorial quality and the powerful message it conveys to its observers. 6. conflict of interest declaration the authors state that no actual or potential conflicts of interest exist including financial, personal or other relationships with other people or organizations within three years of beginning the submitted work that could inappropriately influence, or be perceived to influence, their work. chromatic values in pablo picasso’s early work: a comparison of hues in “science and charity” (1897) and its three oil sketches 41 color culture and science journal vol. 11 (2) doi: 10.23738/ccsj.110204 7. funding source declaration this study was carried out as part of the research project har2016-75131-p “study of the mechanical and dimensional properties of commercially manufactured paint films and their influence in the physical and chemical degradation of modern and contemporary paintings” (promesa, 2017-2019) granted by the ministerio de economía, industria y competitividad (micinn/feder) programa estatal de fomento de la investigación científica y técnica de excelencia, subprograma estatal de generación del conocimiento. 8. acknowledgment the authors acknowledge the ministerio de economía, industria y competitividad (micinn/feder) programa estatal de fomento de la investigación científica y técnica de excelencia, subprograma estatal de generación del conocimiento for having finantially supported part of this research within the promesa project. sonia berrocal and anna velez at mpb are thanked for their assistance during the measurements at the museu picasso. the ifac-cnr authors are grateful to andrea casini, giovanni bartolozzi, and sirpa salenius for their constant technical support and stimulating discussions. 9. short biography of the author(s) marcello picollo ph.d., is a researcher at ifac-cnr. his interests include color measurement, vis-nir hyperspectral imaging, and spot size uv-vis-ir spectroscopic investigations of 2d polychrome objects. costanza cucci got her physics “laurea” and ph.d. in conservation science at the florence university. currently she is a researcher at ifac-cnr. her research focus is on spectroscopic techniques and data-processing algorithms applied to the fields of cultural heritage, environmental monitoring, and safety food controls. lorenzo stefani is a technician in telecommunications at ifac-cnr. he is in charge of the development of hardware and software for computer-controlled instrumentation for the non-invasive and in situ study of artworks. reyes jiménez-garnica – got her degree on conservation & restoration at the universidad complutense de madrid, escuela oficial de conservación y restauración de bienes culturales. from 2002 she has been the head of the departamento de conservación preventiva y restauración del museu picasso de barcelona. laura fuster-lópez phd in conservation from univeristat politècnica de valència (upv). currently she is an associate professor at upv and research focuses on the mechanical properties of cultural materials and the environmental effects on their stability and preservation. anna vila was formed as a conservator and she has a ph.d. in analytical chemistry. vila has worked in the field of conservation science at the art institute of chicago, the centre de recherche et restauration des musées de france, the metropolitan museum of art and at the center for art technological studies in conservation in denmark. at present, she works as a conservation technitian at the university of barcelona. references gage j. (2006) ‘colour in art’, thames & hudson, london. fuster-lopez l., jiménez r., aguado e., andersen c. k., izzo f. c., murray a., picollo m., valcarcel j., vicente a., vila a. (2018) ‘con permiso de picasso. aproximación a los mecanismos de degradación en pintura moderna’, actas de la 19ª jornada de conservación de arte contemporáneo museo reina sofía, madrid, 2018. in press. buswell g. t. (1935) ‘how people look at pictures: a study of the psychology of perception in art’, the university of chicago press, chicago. arnheim r. (1974) ‘art and visual perception’, university of california press, berkley and los angeles. gombrich e. h. (1968) ‘art and illusion: a study in the psychology of pictorial representation’, phaidon, london. gage j. (1999) ‘color and meaning: art, science, and symbolism’, university of california press, berkley and los angeles. borren f. (2016) ‘color psychology and color therapy; a factual study of the influence of color on human life’, pickle partners publishing. parraman c. (ed.) (2010) ‘colour coded’, society of dyers and colourists, bradford (uk). striova j., ruberto c., barucci m., blažek j., kunzelman d., dal fovo a., pampaloni e., fontana r. (2018) ‘spectral imaging and archival data in analysing madonna of the rabbit paintings by manet and titian’, angew. chem. int. ed., 57, pp. 7408-7412. dooley k. a., conover d. m., deming glinsman l., delaney j. k. (2014) ‘complementary standoff chemical imaging to map and identify artist materials in an early italian renaissance panel painting’, angew. chem. int. ed., 53, pp. 13775 –13779. gual m., jiménez r. (2010) ‘ciencia y caridad al descubierto’, colección focus 1, ed. museu picasso, barcelona. jiménez r. (2018) ‘science et charité: restauration, étude, technique et recherches’, in bouvard, émilie, coline zellal (eds), picasso. chefd’oeuvres! parís, gallimard / musée national picasso-paris, pp. 44-49. https://www.konicaminolta.com/instruments/download/instruction_manua l/color/pdf/cm-700d_instruction_eng.pdf zervos c. (2013) ‘pablo picasso catalogue of works, 1895–1972’, new revised edition, ed. cahiers d’art, paris. chromatic values in pablo picasso’s early work: a comparison of hues in “science and charity” (1897) and its three oil sketches 42 color culture and science journal vol. 11 (2) doi: 10.23738/ccsj.110204 wyszecki g., stiles w. s. (1982) ‘color science: concepts and methods, quantitative data and formulae’, wiley and sons, new york. cie publication no 15.2 (1986) ‘colorimetry’ (2nd edition), bureau central de la commission internationale de l'éclairage, vienna. iso/cie 10526 (1991) ‘cie standard colorimetric illuminants’, international organization for standardization, geneva (ch). iso/cie 10527 (1991) ‘cie standard colorimetric observers’, international organization for standardization, geneva (ch). bacci m., picollo m., trumpy g., tsukada m., kunzelman d. (2007) ‘noninvasive identification of white pigments on 20th century oil paintings by using fiber optic reflectance spectroscopy’, journal of the american institute for conservation, 46, pp. 27-37. cultura e scienza del colore color culture and science 64 cultura e scienza del colore color culture and science | 02/14 in questo libro g. d. dimostra l’influenza che il linguaggio esercita sul pensiero, prendendo come esempio i concetti di spazio, genere e colore nelle diverse lingue e analizzando quanto è stato elaborato scientificamente riguardo ai meccanismi della ereditarietà biologica. riporta la grande controversia naturacultura investì le riflessioni sul colore per la relazione tra ciò che l’occhio è in grado di vedere e ciò che il linguaggio è in grado di descrivere; esaminando da una parte le concezioni universaliste, innatiste e dall’altra quelle relativiste, culturaliste che infervorarono il dibattito novecentesco e cioè se la maggior parte della grammatica del linguaggio, ossia tutte le lingue umane, è innata, codificata nel nostro dna, o se viceversa le strutture grammaticali sono conseguenza dell’evoluzione culturale e dell’esigenza di comunicare in maniera efficiente, come sostiene la concezione relativista. molte pagine sono dedicate a william ewart gladstone (1809 1898), politico eminente e importante statista del regno britannico che scrisse nel 1858 un’opera monumentale in 3 tomi: “studies on a cura di renata pompas recensioni guy deutscher, la lingua colora il mondo. come le parole trasformano la realtà. bollati boringhieri, torino, 2013. homer and the homeric age” (studi su omero e l’età omerica), dedicando un intero capitolo a “la percezione e l’uso del colore da parte di omero”. tramite l’analisi minuziosa dei testi notò molte incongruenze nell’uso dei termini omerici di colore che gli fecero teorizzare una sorta di cecità ai colori e una sensibilità ai valori chiaroscurali e di lucentezza. dopo di lui altri ricercatori sostennero la teoria dell’evoluzione storica del senso del colore nei termini di uno sviluppo graduale della sensibilità della retina umana nel corso degli ultimi millenni. lo psichiatra, antropologo e biologo inglese william halse rivers (1864 – 1922) dopo le sue spedizioni tra le popolazioni non civilizzate giunse invece alla conclusione che le differenze fra le terminologie di colore non hanno nulla a che vedere con i fattori biologici. 6502/14 | cultura e scienza del colore color culture and science nel 1969, in un periodo che conosceva la completa affermazione della visione culturale della visione del colore, due ricercatori di berkley, brent berlin e paul kay, pubblicarono – in controtendenza – uno studio che proponeva una gerarchia evolutiva nella sensibilità ai colori, che destò clamore, “basic color terms: their universality and evolution” (i termini basici di colore: la loro universalità ed evoluzione), benché riprendesse la sequenza ipotizzata dal filosofo e filologo tedesco lazarus geiger (1829 – 1870) un secolo prima. infatti geiger aveva ricostruito una sequenza cronologica completa dell’emergere della sensibilità ai diversi colori prismatici, seguendo lo schema dello spettro visibile: rosso, giallo, verde, blu e violetto dichiarando: “il fatto che i termini di colore emergano seguendo una successione ben definita, e che questa sia identica dappertutto, deve avere una causa precisa”. berlin e kay oltre alla sequenza evolutiva degli 11 colori – bianco, nero, rosso, verde, giallo, blu, marrone, viola, rosa, arancione, viola intuirono che,al di sotto delle divergenze superficiali, lo schema universale si manifesta nei ‘fuochi’ dei diversi colori, che chiamiamo anche esempi ‘prototipici’, che sono biologicamente determinati e indipendenti dalla cultura. in seguito si risultò che in molte lingue il marrone non viene dopo il blu, che i fuochi principali, pur con molte eccezioni, sono 6: bianco, nero, rosso, verde, giallo e blu. l’unica regola che è rimasta realmente priva di eccezioni è quella che indica nel rosso il primo colore dopo il bianco e il nero a ricevere un nome. oggi è acclarato che gli individui sono in grado di cogliere le differenze tra i colori senza tuttavia dare loro nomi distinti e i ricercatori sono propensi a ritenere che la nostra lingua madre non limiti né la nostra capacità di ragionamento logico, né la nostra capacità di comprendere idee complesse. tuttavia, sostiene deutscher, il linguaggio interferisce con l’elaborazione visiva a un livello profondo e inconscio; giungendo a supporre che il lessico di colore delle diverse lingue del mondo possa essere la causa delle differenze nella percezione del colore. cultura e scienza del colore color culture and science 22 cultura e scienza del colore color culture and science | 04/15 1. introduction the objective of this paper is to ascertain contemporary italian linguistic categorization of the macro-color concept blue, and compare the results to english interpretation of the same tasks. native italian speakers affirm that they habitually use three blue color terms: blu, azzurro, and celeste; often idealizing azzurro over blu, as being “more italian”. i propose that according to the task results contemporary blu [blue] is the more primary and deeply entrenched basic color term (henceforth bct); azzurro [azure light blue] could also be a bct, but should be considered a secondary bct; and celeste [sky blue pale blue] is a subordinate color term. english interpretation of the same color object/ concept associations used in this questionnaire is different due to the lack of a second english monolexemic basic blue color term and to the difference in culturally specific blue color term collocations. what are the italian blue term semantic relations? do azzurro and celeste violate the criterion that a bct not be a hyponym of another color word, i.e., blu [1]? does the semantic relation between the terms blu and azzurro respond to the cognitive need to differentiate between the colors of the sky and the water? is the principal task color term object/ concept association, based on the cognitive linguistic approach to linguistic entrenchment, an original valid method to measure basicness? various verification measures of basicness are employed to answer these queries. 2. background the spectrum may be partitioned into different color terms according to language and the corresponding culture. color lexemes evolve dividing the color space into more specific semantic concepts. current research, since berlin and kay, generally considers blue to be the last primary bct to emerge in language. some languages present a variation of blue lexicon; often displaying two distinct blue terms; one for a generic blue -primary bctand one for a more specific blue -secondary bctin english recognized as a tonal variation of “blue”. the possibility of there being a twelfth bct has been theorized by [1][2], among others. researchers have proposed a twelfth bct as being another “tone of blue” — also referred to as dual 1jodi l. sandford jodi.sandford@unipg.it 1department of letters, university of perugia a cognitive linguistic usage perspective: what is italian blu, azzurro, celeste? do english agree on blue semantics? lexicalization of blue — in different languages e.g., italian, maltese, greek, polish, russian, and turkish, [3][4][5][6][7][8]. bct criteria are listed as: i. it is monolexemic, ii. its signification is not be included in that of any other bct, iii. it must not be restricted to a narrow class of objects, iv. it must be psychologically salient, i.e., occur at the beginning of elicited lists of color terms, and have stability of reference across informants and occasion of use, v. if doubtful it should have the same distributional potential [1]. the specific bct criteria of interest this study are: iii, it not be restricted to a narrow class of objects, (the occurrence in a large number of domains reveals the degree of entrenchment), and the problematic ii. its meaning must not be hyponymic (see glossary for a definition of several terms). the definition of each color term provides an initial idea of what they are understood to mean, and in what contexts the meaning can vary. in some dictionaries [9] [10] blu is defined as a dark azzurro, and is used with the expressions: cielo blu [blue sky], mare blu [blue sea] | avere sangue blu [have blue blood]; though blu is translated as blue, dark blue, and navy blue. blu is more productive, blue compounds in italian are currently constructed with blu + another term, e.g.; blu marina [navy blue], which of course do not appear separately in dictionary entriesi. there are only three entries of blu lexemes in the italian dictionary [11]. azzurro is defined as the color of a clear sky, somewhere in between celeste and turchino; translated with blue, light blue, azure, sky blue; with expressions such as occhi azzurri [blue eyes] | principe azzurro [the ideal groom, a prince in shining armor] | gli azzurri the italian national sport team color, | azzurro del cielo [the blue of the sky]. azzurro is sited as synonymous with blu [blue], celeste [sky blue], turchese and turchino [turquoise], and pervinca [periwinkle]. it entered italian before blu and is listed with over fourteen entries in the dictionary, including a verb form: azzurrare [9][10]. celeste, translated as sky blue, light blue, baby blue, azure, is defined as analogous to azzurro, specifications of which are celestino [pale blue], and acquamarina [7] [8]. there are only two dictionary entries with the color root celest[11]. turchino, with direct reference to the stone turquoise turchese, is described as of azzurro cupo [deep or dark], and blu [12]. 2304/15 | cultura e scienza del colore color culture and science the principal test of this study was developed to apply a cognitive linguistic approach to verify the level of entrenchment of the color term object/concept association. the multiple senses of color terms create a network that is accessed and elaborated online for the speaker to identify the meaning of the color term in use. the identification of color term entrenchment and distributional criterion of occurrence in a large number of domains should give us a sense and level of basicness and lexical status. this approach was developed following langacker [13] and other cognitive linguists who sustain a functional approach to linguistic investigation. they acknowledge the grounding of language in embodied experience and social interaction, insisting that this interaction is critically dependent on conceptualization. conceptualization is once again constrained by four aspects: human cognitive capacities, the nature of reality, convention, and context [14]. therefore, meanings experienced more often, will be encountered more frequently in specific contexts or associations, and will in turn become more entrenched on an individual level and conventionalized in the speech community. 3. methodology this study was carried out in five different phases. each phase had a specific objective and served to initially confirm or contradict the various results. the first, and most pertinent, phase was the blue color association test; constructed to verify color term entrenchment and occurrence in a number of domains. the second phase was the same blue color association test translated and presented to a pilot group of native american english speakers, to verify the cross linguistic saliency of the color object/concept associations. the third phase comprised a colorlist task to confirm the three blue color terms’ cognitive saliency in italian. the fourth phase was a color-patch naming task in italian; and the fifth phase was a “kind of” survey to verify informant signification and stability of reference in italian. the italian informants were students at the university of perugia. they were from mixed regional backgrounds across italy. the american english informants were a variegated group of native speakers. the first and second phase tasks asked informants to associate 10 blue color terms to 38 different italian prototypical object/concepts. this task was carried out by two groups of italian university students (49 and 48) for a total of 97 informants (mean age 23). a comparison group of 15 native american english speakers carried out the same task translated into english [9-10] (mean age 45). azzurro has numerous possibilities, medium blue, sea blue, bright blue, heraldry blue, sapphire; i opted toward the phonetically more similar term azure. a paper questionnaire was handed out to the class of students. one page contained the instructions and one page the list of items with a blank box next to it, where the informant wrote one of the 10 color terms provided. there was no time limit. informants took no more than 15 minutes. the prototypical object/concepts used as stimuli in this task were selected from online dictionaries, databases, and idiomatic expressions, which were double checked through google and confirmed as being the most frequent. the 10 colors selected to associate with the stimuli were the three most frequent terms blu, azzurro, and celeste, with the four possible inflected color terms: blu-astro, azzurr-ognolo, azzurr-ino, and celest-ino (see endnote), with three other salient blue color terms, turchino, oltremarino, and indaco. all of these terms except azzurrognolo appeared later in the listing task, see table 1. the third phase, the color-list task, was carried out by 65 university students (mean age 22). it aimed to verify the cognitive salience of the three blue terms. this task was based on davies and corbett [15]; informants were asked to write down as many color terms as they could in five minutes. the data were then analyzed following the cognitive salience index elaborated by sutrop [16], taking into account two important aspects of bct criteria: term frequency and mean position. the cognitive salience index is calculated: s = f/(n x mp), where s is salience, table 1 the 10 blue names in italian and english, color patches set to rgb coordinates indicated by moroney in the italian section of the color thesaurus, hewlett packard laboratories. english translation of italian blue color rgb color coordinates blue blu red=20, green=15, blue=180 bluish, grey-blue bluastro red=50, green=65, blue=120 azure azzurro red=60, green=155, blue=240 light blue azzurrino red=115, green=175, blue=245 light bluish azzurrognolo red=120, green=145, blue=205 sky blue celeste red=129, green=225, blue=255 pale blue celestino red=180, green=235, blue=255 ultramarine oltremarino red=40, green=25, blue=195 turquoise turchino red=10, green=185, blue=205 indigo indaco red=20, green=15, blue=120 24 cultura e scienza del colore color culture and science | 04/15 f is frequency in the lists, n is number of informants, and mp is mean position rank in the lists provided by the informants. the fourth phase, the blue color-patch naming task, was carried out in a darkened room with a projection of numbered color patches presented on a screen. the stimuli were presented one at a time. they remained on the screen for 10 seconds. 30 informants (mean age 26) wrote the color names in the box next to the slide number. the 30 color patches were set to color rgb parameters distinguished by moroney for the italian color terms [17]. the randomized 10 blue color patches corresponded to the 10 color words tested in the first phase, which had also emerged in the third phase (see table 1). the informants were tested twice on different occasions to verify the consistency of naming. the fifth phase of this study, the “kind of blue” was carried out by a group of 30 informants (mean age 26). they were asked which blue was a kind of blue, combining the three terms, blu, azzurro and celeste, in couples, e.g., is azzurro a kind of blu? the informants answered yes or no. 4. results “color association” task result data are presented in percentages in figures 1 and 2. the total 3686 responses given by 97 italian informants resulted in 30% of the objects associated with blu (blue), 7% bluastro (blue-grey), 19% azzurro (azure), 4% azzurrognolo (dull bluish), 4% azzurrino (light bluish), 11% celeste (sky blue), 5% celestino (pale blue), 5% oltremarino (ultramarine), 7% turchino (turquoise), 6% indaco (indigo), and 3% no answer. if we group the terms according to tone (dark, medium, light) the division becomes 48% blu, 34% azzurro, and 16% celeste. the spread between the three predominant blue color terms does not vary significantly, and the rank remains unchanged. fig. 2 shows marked differences in english association percentages with the corresponding terms blu, bluastro, azzurro, celeste, and no answer. the color/object associations in english actually seem more evenly distributed, demonstrating the subordinate value of most of the blue color terms, and the saliency of blue with a higher percentage of associations. a predominance of blu, azzurro, and celeste, in that order emerges in these results. figure 3 presents the total italian results, each color term and the 38 associated items. each item is presented in table 2 with the color term with the highest percentage of associated object/concepts agreement. the object/concepts associations with the highest percentage of agreement are: 85% sangue blu, 84% fata turchina, 82% principe azzurro, 78% caschi blu, 70% jeans blu, 64% madonna celeste, 63% bollino blu, 63% tute blu, 59% fifa blu, 57% telefono azzurro, 55% cielo azzurro, 55% fiocco azzurro, 54% strisce blu, 52% camicia celeste, 51% machine blu, 50% mare blu, 51% pesce azzurro. of the 38 object/concepts, the number that were mostly associated with a specific color are 19 with blu; 10 with azzurro; 2 with celeste; 2 with celestino; 2 with turchino; 1 with azzurrino, 1 with bluastro, and 1 with oltremarino. the most prototypical object for blu is sangue (85%); for bluastro is fumo (38%); for azzurro is principe (82%), for azzurrognolo is fumo (21%); for azzurrino is airone (23%); for celeste is madonna (64%); for celestino is nuvole (23%); for oltremarino is sale (39%); for turchino is fata (84%) and for indaco is tute (12%). the english translation of the object/concepts may be found in table 2. a significant result was also the consensus between the two italian groups, even though within the group there were significant differences in color/object association. 59% (169 of 380 responses) of possible color-object/ concept associations were made by the same number or ±1 of informants in each group separately, e.g., caschi and blu were associated by 38 people in the first group and 38 in the second group; cielo azzurro was associated by 26 and 27. and only 4% (17 of 380) of the associations made by the two groups were different by >5 of the number of informants. that is to say that the correlation coefficient was statistically relevant between the two italian groups for blu, azzurro, azzurrognolo, celeste, celestino, turchino, and indaco (all between 0.956 and 0.720). figure 1 (left) percentage of italian blue color association of 38 objects by 97 informants. figure 2 (right) percentage of english blue color association of 38 objects by 15 informants. 2504/15 | cultura e scienza del colore color culture and science figure 3 italian blue color term 38 object/concept associations by 97 informants (english translation of the items is indicated in tab.2). table 2 also shows the percentage of association results for english. the results are significantly different. the highest agreement was 80% for blue flag, 73% for sky-blue sky, blue team, greyblue heron, and grey-blue smoke. only 29% (11 of 38) color object/concept associations were the same in both languages, and the percentages varied notably; the number of “no answers” is relevant in color association saliency. table 2 lists the change of the color term associated next to the item and the percentage of agreement. the difficulty in responding by the english informants clearly indicates the lack of cultural entrenchment of the italian prototypes. “color-listing” task results reveal two cognitively important aspects: the term frequency and position in the list. following sutrop [16] color term basicness is estimated independent of the length of any particular list; see results in table 2. the color term is given followed by frequency in the lists of the 65 informants, and the corresponding rank; the mean position in each list and the corresponding rank within the total list of 134 different colors listed; the cognitive salience index and the final cognitive salience rank. the cognitive salience ranking of blu in fourth position, azzurro in ninth, and celeste in thirteenth, corresponds in essence to the results acquired through the cognitive linguistic association task. “color-patch naming”results show that the majority of the informants called blu 6 of 10 blue color patches (not azzurrino, celeste – celestino, nor turchino), see table 4. the patch considered blu was named blu by 94%, azzurro was named blu by 74%, azzurrino was named azzurro by 60%, celeste was named celeste by 80%. the half tone azzurrognolo was named blu by 80%, bluastro was named blu by 65%, oltremarino and indaco were named blu by 67%. color 26 cultura e scienza del colore color culture and science | 04/15 rank ital. ass. 38 obj/conc. object/concept in italian color max. agreement % agreement italian % agreement english object/concept in english 1 sangue blu 85% 47% blue blood 2 caschi blu 78% 27% blue helmets 3 jeans blu 70% 47% indigo jeans 4 bollino blu 63% 47% blue sticker 5 tute blu 63% 53% blue collar 6 fifa blu 59% 33% no answer fear 7 strisce blu 54% 40% blue lines 8 macchine blu 51% 40% blue cars 9 mare blu 50% 33% azure sea 10 bandiera blu 47% 80% blue flag 11 tasto blu 39% 27% no answer button 12 freccia blu 37% 33% no answer arrow 13 cartello blu 36% 53% blue sign 14 energia blu 33% 27% ultramarine energy 15 fascia blu 31% 60% no answer band 16 occhi blu 30% 40% pale blue eyes 17 treno blu 28% 47% no answer train 18 mani blu 27% 27% blue hands 19 pellicola blu 26% 33% no answer film 1 principe azzurro 82% 33% blue prince 2 telefono azzurro 57% 27% blue phone 3 cielo azzurro 55% 73% sky blue sky 4 fiocco azzurro 55% 33% blue bow 5 pesce azzurro 51% 40% ultramarine fish 6 squadra azzurra 47% 73% blue team 7 nastro azzurro 42% 20% sky blue ribbon 8 pomeriggio azzurro 36% 27% sky blue afternoon 9 pizzeria azzurro 23% 47% no answer pizzeria 10 porto azzurro 23% 27% ultramarine port 1 madonna celeste 64% 27% no answer madonna 2 camicia celeste 52% 40% blue shirt 1 nuvole celestino 23% 33% pale blue clouds 2 gabbiano celestino 18% 60% grey-blue seagull 1 fata turchina 84% 20% light blue fairy 2 capelli turchini 47% 20% blue hair 1 airone azzurrino 23% 73% grey-blue heron 1 fumo bluastro 38% 73% grey-blue smoke 1 sale oltremarino 39% 27% pale blue salt table 2 the maximum percentage of informant agreement on the color associated with each of the 38 object/ concepts; grey background for same color-object/concept association in both language groups; bold print for majority agreement. color name frequency frequency rank mean position (mp) mp rank cognitive salience index cognitive salience rank rosso 63 3 3.71 11 0.2612 1 giallo 62 4 4.70 13 0.2029 2 verde 61 5.5 5.42 14 0.1731 3 blu 60 7.5 6.03 18 0.1531 4 nero 64 1.5 7.89 22 0.1248 5 bianco 64 1.5 8.28 24 0.1189 6 arancione 58 9.5 8.48 25 0.1052 7 viola 61 5.5 9.61 30 0.0977 8 azzurro 54 11.5 9.59 29 0.0866 9 rosa 54 11.5 9.66 31 0.0860 10 marrone 60 7.5 11.16 37 0.0827 11 grigio 58 9.5 11.34 38 0.0787 12 celeste 44 13 10.63 34 0.0637 13 lillà 34 15 13.38 50 0.0391 14 fucsia 37 14 15.10 63 0.0377 15 indaco 29 18 12.96 48 0.0344 16 beige 30 16.5 15.20 64 0.0304 17 oro 30 16.5 15.93 71 0.0290 18 porpora 20 21.5 13.70 51 0.0225 19 rosso bordeaux 20 21.5 14.20 55 0.0217 20 table 3 first 20 colors in color listing cognitive salience rank of 65 informants; grey background for blue terms 2704/15 | cultura e scienza del colore color culture and science referents for the color patches used in this task also correspond to the legend in figures 1 and 2. “kind of blue” task responses show 93% of italian informants responded affirmatively to azzurro as a kind of blu, and 100% affirmed that celeste is a type of blu, but blu is not a type of azzurro, nor celeste. only 10% of informants claimed that celeste was a type of azzurro. 5. conclusions as expected bct’s can be distinguished from non-bcts by the high scores on the first phase task entrenchment and occurrence and the third phase task cognitive saliency, and the fourth and fifth phase task significations and stability of reference results. the use of a specific set of the 10 most common blue terms in italian and the lack of restrictions between bct and nonbct provided a mode of testing the relationship between the three most common blue terms: blu, azzurro, and celeste. the subordinate terms were associated less often than the bct term(s). moreover, the use of all the terms determined a decrease at the expense of the more specific terms. this provided a further check on robustness and stability of the bct terms. in the past azzurro has been used as the prototypical basic blue, grossman [18] identifies it as the blue arcilessema and translates blue with it. diagrams and color systems published in the past translated labels and indications of blue with azzurro; contemporary texts translate blue with blu, e.g., there is no change in the use of the abbreviation rgb (red-rosso, greenverde, blue-blu), and the respective diagrams of color spaces; identification of receptor cells r-g (rosso-verde), b-y (blu-giallo), and primary colors (red-rosso, blue-blu, yello-giallo). moreover, many recent videos and books for children teach blu as the basic color not azzurro. quantification of a corpus analysis in this sense may be of interest for future investigation. this study lends support to the claim that there has been a semantic shift in blue lexicalization. i argue that azzurro was previously the italian blue primary bct. it has been present in italian for longer and has diachronically developed a more elaborate grammaticalization (see blu named blu by 94% azzurro named blu by 74% azzurrino named azzurro by 60% celeste named celeste by 80% azzurrognolo named blu by 80% bluastro named blu by 65% oltremarino named blu by 67% indaco named blu by 67% turchese named verde-acqua by 55% celestino named celeste-chiaro by 50% table 4 fourth phase color patch naming in italian. endnote). it no longer demonstrates the same saliency, however, as it did in the near past. summarizing, the study informants identified azzurro as a type of blu, and but not celeste as a type of azzurro. though they may be considered synonyms, there is a different degree of inclusion in contemporary italian; the hypernym is now shifted to blu and the hyponyms are azzurro and celeste. in this sense, according to the “non hyponym” bct criteria azzurro would not be a secondary bct. considering, the first phase task, however, a more dynamic analysis of color term entrenchment, and an apparently valid measure of basicness and “application to a broad range of objects”, azzurro still has robust associations and collocations in both conceptual metaphoric and metonymic extensions. for example, the informants associated the sea with blu, the sky with azzurro, blood with blu, eyes with both blu and azzurro, and the prince with azzurro. the results of the four phases of this study converge to suggest that contemporary italian use of blue color terms reveals a twelfth bct, a tone of blue. azzurro has not yet been pushed out of basicness, but may be on its way. it still has a high cognitive salience rank. although it is evident that the number and age of the italian and english informants differ notably in this study, the general tendency of lack of entrenchment of these color associations for the english pilot group is convincing. furthermore, all the tasks verify current italian conceptualization and dual lexicalization of blue as language specific and not corresponding to english. afterword2015 in this revised version of my 2011 paper i have added two tables to give more visual support to the text. i have also supplemented it with some explanation of the results in table 3, and included a brief glossary. the principle aim however is to acknowledge recent publications that have continued to address the linguistic and cognitive entrenchment and conventions for blu, azzurro, and celeste for italian speakers [19] [20] [21] [22] [23] [24] [25]. valdegamberi, paggetti, menegaz sustain that there is evidence in favor 28 cultura e scienza del colore color culture and science | 04/15 of the hypothesis of the existence of the twelfth basic color category in the italian language [24]. ronga, banzanella, struddsholm, salvati include azzurro in the group of bcts analyzed in their study, and find blu rating over azzurro both in the type to token ratio and in the hapax legomena (i.e., types mentioned by a single speaker) with little variation [25]. ronga’s earlier findings vary from these others, in that she stated “in italian, in fact, azzurro (light-blue) is considered a basic colour term and not part of the realm of blue” [3]. her paper gives and excellent overview of the history of azzurro, revealing, i believe, the previous primary basicness of the term. paramei, d’orsi, menegaz affirm, “our results provide additional psycholinguistic evidence that for italian speakers at least two colour terms are necessary to name the blue area, blu ‘dark blue’ and azzurro ‘light-and-medium blue’. both were shown to behave as basic colour terms, in linguistic and previous psycholinguistics studies” [22]. nonetheless, a predominance of current research confirms the semantic shift of blu into a more salient role and azzurro into a more secondary position. some researchers advance the possibility of regional influences, and/or generational differences. thierry et al. findings [26] uncover an effect of native language on implicit color discrimination, and how language learning seems to modify the location and extent of categorial perception, which may reorganize the representation of perceptual color space. it is conceivable that the second language acquisition, which is now required in italian elementary schools, and is usually english, may be speeding up a shift in the perception and the semantics of blue. the italian informants were university students from mixed regional backgrounds across all of italy, but all had studied scholastic english for 4-8 years. clearly the general presence of english blue in italian daily life, through computers, internet, advertisements, etc., can in itself contribute to a shift in linguistic convention. these factors may be an explanation of the displacement of a cognitive reference point, of the perceptual and conceptual variations introduced by different languages that use variations of blue. as desgrippes states, “the cognitive representation of a color is dynamic: it can evolve with diachronic language variation or with language shift, and both older and newer representations remain retrievable depending on the task at hand” [27], which seems pertinent to this case, that is, the present findings may differ from past studies. to summarize i return to the initial questions posed: what are the italian blue term semantic relations? my results point to blu as the primary bct, azzurro as a secondary bct, and celeste as a subordinate color term. do azzurro and celeste violate the criterion that a bct not be a hyponym of another color word, i.e., blu? i would say that azzurro does, though it ranks high in saliency for the informants of these questionnaires, and hence, should still be considered a bct nonetheless. does the semantic relation respond to the cognitive need to differentiate between the colors of the sky and the water? this differentiation seems to still be pertinent in the use of blu and azzurro in italian. in english the sky is blue or sky blue, but the water, referring more often to the ocean than the sea, may be blue, grey, or green. the sea is azure. is the principal task color term object/concept association, based on the cognitive linguistic approach to linguistic entrenchment, an original valid method to measure basicness? yes, it has demonstrated to be an effective method to measure basicness. this type of functional or usage-based approach to linguistic investigation is a practical means to verify use of language. cognitive linguistics sees language as grounded in embodied experience and social interaction, which is critically dependent on conceptualization that is based on linguistic entrenchment; i.e., “the strength of conventional constraints to aspects of word meaning that have attained some sort of default status” [12]. therefore, meanings experienced and attributed more often will be encountered more frequently in specific contexts or associations, and will become more entrenched in the individual’s conceptualization and conventionalized in the community of speakers. this paper suggests that blu, though still different than english blue, is undergoing a semantic shift that is detracting some of azzurro’s and celeste’s vigor. glossary entrenchment: a color term may be associated with numerous objects, the greater the number of associations and the greater the distribution of occurrence in a large number of domain matrices, the higher the level of entrenchment of the color term object/concept association; the progressive entrenchment of configurations that recur in a sufficient number of events are then established as cognitive routines [11, 28]. saliency: a color term is salient if it is readily elicitable, occurs in the idiolects of most speakers, and is used consistently by individuals and with a high degree of consensus among individuals [29]. 2904/15 | cultura e scienza del colore color culture and science consistency: consistency of color usage relates to the probability that a color name, if used by a given subject on the first presentation, will be used again on the second one [30]. acknowledgements i would like to thank the anonymous reviewers who offered helpful comments and suggestions on previous versions of this paper. notes i the italian dictionary online “grande dizonario hoelpl italiano di aldo gabrielli, hoepli, 2011” and “il nuovo zingarelli – vocabolario della lingua italiana” (10th edition nicola zanichehlli sp.a. bologna, 1990, show only the following entries as derivatives, with my translations of the definitions: blu: bluastro [adj. type of blue], blucerchiato [adj. circled in blue], blue-jeans [engl. n. blue colored cotton pants], blues [engl. n. a type of music or dance], bluesman [engl. n. singer or executer of blues], bluette [fran. adj. type of blue, light turquoise, n. that color blue]; azzurro: azzurrabile [adj. being able to get on the national soccer team referred to as the “azzurri”], azzurraggio [n. being able to make a yellowish substance white by adding that color (azzurro)], azzurramento [n. treatment of lenses, which takes on a bluish cast, to diminish reflection, making more transparent], azzurrare [v. tr. to dye that color (azzurro)], azzurrastro [adj. a color that reminds you of that color azzurro], azzurrato [v. past participle of azzurrare; adj. lenses that have been treated to diminish reflection], azzurreggiare [v. intr. that which tends to or to be that color (azzurro)], azzurrescenza [n. that which tends to that color (azzurro)], azzurriccio [adj. tending toward that color (azzurro)], azzurrigno [adj. a dull version of that color (azzurro) tending towards grey], azzurrino [adj. tending toward a light delicate version of that color (azzurro), n. the color], azzurrità [n. the quality of being that color (azzurro)], azzurrite [n. a mineral, used as a dye], azzurrognolo [a pale, greyish, or faded version of that color (azzurro)]; celeste: adj. --the first definitions regard first the sky and the heavens in reference to the supernatural, only the later entry refers to “the color of the sky free from clouds”, etc.-the only derivative that includes its root is celestino, the first entry, [adj. a light form of that color (sky blue)]. n.b. the nuovo zingarelli dictionary includes a color atlantis that lists 11 compounds with the color blu: blu notte, blu di prussia, blu di parigi, blu oltremare scuro, blu oltremare chiaro, blu cobalto, blu azzurro manganese, blu d’oriente, blu pavone, blu ceruleo, blu turchese, blu zaffiro; and only one term with azzurro: blu azzurro manganese, and only once celeste. bibliography [1] berlin, b., p. kay, basic color terms: their universality and evolution, university of california press, berkeley, [1969] 1991. 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[30] robert m. boynton, insights gained from naming the osa colors, color categories in thought and language, clyde l. hardin and luisa maffi (eds.), cambridge university press, pp. 135-150, cambridge, 1997. original reference: sandford j.l. “blu, azzurro, celeste what color is blue for italian speakers compared to english speakers?”, proceedings of the eighth national color conference. gruppo del colore – siof alma mater studiorum università di bologna, facoltà di ingegneria, bologna, italy, 13-14 settembre 2012. in colour and colorimetry. multidisciplinary contributions. vol. viii b, m. rossi (ed.) – dip. indaco – politecnico di milano. maggioli editore, pp.281-288, santarcangelo di romagna (rn), 2012. isbn 88-387-6137-x. ean 978-88-387-6137-9. 63 color culture and science journal vol. 11 (2) doi: 10.23738/ccsj.110207 two theories for a model: the “querelle” between klee and ostwald anna marotta1 1department of architecture and design, polytechnic of turin, anna.marotta@formerfaculty.polito.it corresponding author: anna marotta (anna.marotta@formerfaculty.polito.it) abstract framed in the time of history, the comparative theories of colour expressed not only give us a sort of "distillate" of chromatic culture, but also constitute a precious instrument of investigation, useful in the syncretic comparison of thoughts and positions, sometimes very different from each other, as in the case of the "querelle" between paul klee and wilhelm ostwald, a question proposed here again. this type of comparison, addressed in the 2017 conference on circular models, is developed here on biconical models, starting with those of wilhelm ostwald and paul klee, assuming and confirming the classification and analytical structuring of the models through the parameters adopted in polychrome (marotta 1999). it should be remembered that klee publicly took a stand against ostwald's theory and his model, but in fact assumed the essential geometry of the model of the chemist himself. the present investigation therefore aims to better clarify (in the face of formal analogies) the differences in objectives and scientific and artistic content. the work confirms that the position taken by klee and his followers was partly prejudicial, linked to his artistic training and related experiences in the field, to which his intellectual milieu was no stranger. the position of the chemist is symmetrical, linked to the rigor of his scientific profile (although completed by the practice of painting). the substantial rapprochement of their respective convictions confirms the open-mindedness and maturity to which the two protagonists have arrived. in addition to describing cultural matrices, parameters and essential characteristics of the models examined, of particular interest is the scope of the applications already put in place of the models, or possible future developments, also connected to new methodologies (such as virtual and digital) in the color project, up to the experiments in concrete and material production. the most innovative digital virtual modes will allow to verify the analogies and differences (of forms and contents) of the respective models. keywords comparative theories of colour, colour models, paul klee, wilhelm ostwald, history of colour, polysensory received 24 june 2019; revised 09 july 2019; accepted 12 september 2019 two theories for a model: the “querelle” between klee and ostwald 64 color culture and science journal vol. 11 (2) doi: 10.23738/ccsj.110207 1. introduction the synoptic picture of the models, which over time invert and represent the relative theories of colour, crystallizes (through images) a syncretic process in which the same theories have been produced and transformed. the comparison also formal of thought through chromatic models (marotta 1999) confirms its usefulness, even in the speculations sustained and represented by digital. in confirmation of this, a significant case could be constituted by the comparison still under development between the theories of paul klee and wilelm ostwald and their respective visualizations (both with a double cone configuration), between analogies and differences. the present contribution should therefore be considered as an investigative phase, preliminary to more precise applications and investigations through advanced technologies, now underway. from a consolidated and "static" situation, contemporary reality leads us to new experimentations to decline virtual and digital modes, also in the chromatic field. this type of comparison, (dealt with in the xiii conference of colour on circular models (marotta 2017)), will be developed on biconical models, starting from ostwald's and klee's, assuming and confirming the classification and analytical structuring of the models through the parameters adopted in polychrome (marotta 1999). the most innovative virtual and digital modes will allow to verify the analogies and differences (of forms and contents) of the respective models. it should be remembered that klee publicly took a stand against ostwald's theory and his model, but in fact assumed the essential geometry of the model of the chemist himself. the present study therefore aims to better clarify (in the face of formal similarities) the differences in scientific and artistic objectives and contents. in fact, in the bauhaus of the early 1920s, the apparent rejection of the material aspects of colour may have originated not only from the mystical tendencies of the school, but from more concrete factors (geelhaar 1972). at the root of the "querelle" between klee and ostwald, it should be remembered that itten's master, hoelzel, was a declared opponent of the chemist's theory of colours. of the latter, we recall that in 1909 he was awarded the nobel prize for his research in physical chemistry, a discipline he invented himself. an amateur painter, accustomed from childhood to preparing pigments, ostwald developed a deep interest in colour in all its aspects. a tenacious (and amateur) painter, he spread his theories in the firm belief that there were absolute colour principles for art, to which he himself adhered: not following them led to the creation of works that were not "correct". he was in open disagreement, therefore, with freer artists and less strictly bound to his theories, consistent also with the socialist convictions of the time. some critics, such as max doerner, mocked the chemist: "to painters it seemed quite amusing that professor ostwald, analyzing titian, announced that the blue of a cloak was two tones too high or too deep! it was simply titian's typical blue. 2. confirmations and denials of a heated and broadened debate klee's theoretical and speculative activity is also rich in acute annotations (still relevant today), many in the psychological field (cherchi 1978), when he states: "even space is a temporal notion [...]. in the work of art there are paths prepared for the eye of the spectator, who is about to explore, as an animal grazing in a meadow (in music as we know, channels guide the ear, while the theater combines the two possibilities). [...]. the musical work has the advantage of being perceived exactly in the order of succession in which it was conceived (klee 1920). even today, the instrumentally recorded path of the pupils who "palpitate" in the analysis of eye trekking is the most current scientific response to what klee observed during his lessons at the bauhaus: "music evokes spaces but does not possess them. while it is possible to construct visual itineraries in front of a painted canvas and the eye can in turn return to the starting point, hurry towards the boundaries of the surface and stop at will in any of the chosen areas, the ear is instead dragged forward by the music and its only resource to order the impressions, is to appeal to memory" (klee 1956). it is hardly necessary to stress how the relationship between sound and colour (in klee as in kandinsky) is never only synaesthetic, that is to say limitedly aimed at evoking or representing sensory experiences, also covering rhetorical purposes up to symbolic functions (marotta 1999). the strong matrix, common to the two artists, must be recognized in the conception of the wide and articulated circularity and interpenetration of all the arts, all understood with a single objective: the promotion of spiritual values in a world to be reconstructed, especially after the great war of 1914-18. the canon of the chromatic totality, a model developed by klee, can assume in this sense a significant value of cosmic totality. it is then demonstrated how wide and elevated are the connections between terms such as "voice, canon, chord", also borrowed from the musical vocabulary: "each colour starts from its own nothing, that is from the top of the near colour, first slowly and then more and more growing until it touches its own top; it then slowly decreases, towards its own nothing, that is towards the top of the other adjacent colour. but there's still something: on the record the two theories for a model: the “querelle” between klee and ostwald 65 color culture and science journal vol. 11 (2) doi: 10.23738/ccsj.110207 colours don't sound with one voice, as it might seem from the chain, but in a sort of three-voice chord. this representation is designed to show us the three-voice movement and to follow the process. as a canon, the voices attack each other one after the other; in each of the three main points a voice culminates, another voice begins to play slowly and another one is lost. this new figure could be called the canon of totality" (figs. 1 and 2) (klee 1956). visually comparing ostwald's double-cone colour model with klee's canone della totalità cromatica (illustrated, among other things, in a lecture at the bauhaus on 19 december 1922), it is impossible not to grasp the formal derivation of the kleean figure from the ostwaldan figure. both models have a double-cone structure: at the ends of the vertical axis there are respectively white and black, while on the central section, at the intersection of the two cones, there is the chromatic circle. in ostwald's model, the pure colours, arranged around the circumference of the circle, can be six, twelve, twenty-four or more, with the respective complementary colours (always diametrically opposed) located in circular sectors of equal size; while in klee's canon of totality only three basic colours are indicated, arranged around the centre of the double cone, with a much sharper spiral pattern, a figure considered by the author as an emblem of perfect geometric and dynamic synthesis. the above considerations confirm the derivation from ostwald of klee's canon of total chromaticity, which functionally adapts the model of the german chemist although he does not share the rigid and static approach to the expression of dynamic colour, according to his own convictions. from the comparison, and also taking into account the chronology, one can legitimately assume that klee derived from ostwald the setting for his canon of the chromatic totality, considering it adequate, functional to the expression of the movement of the colour he studied ("red in red, in other words the scale of red diluted to deep red, in all its extension or partially") although he does not share the precise "science" of ostwald, klee does not accept his ideas on the harmonic accord of colours (ostwald 1922). however, the bernese does not miss an opportunity to underline the diversity of his approach: in the lesson dedicated to order in the field of colours, held at the bauhaus on 28 november 1922, the swiss master recalls that: "there are, as is well known, many theories of colors. for example, we have goethe's theory, which was created to refute newtonian statements". it is the most exhaustive treatment of his time on the physiological, physical and chemical aspect of colors. the author continues, "a chapter is also devoted to the sensitive-ethical effect of colours. more ancient traces of a theory of the colours of painting can be found in leonardo, dürer and others. now other colour theories have also been formulated; today two are being discussed: hoelzel and ostwald; but we are not a colour industry or a chemical dyeing plant, we must be free and have all the possibilities at our disposal". the importance attributed by the artist from bern to the psychological component and instead neglected by the "men of science" (here it is not by chance that klee insists on repeating the reference to ostwald) is certainly a decisive argument of klee's dissent: "those who study colours from a scientific point of view are generally concerned with providing logical-mathematical evidence. and so, the psychological aspect is neglected; as ostwald does, for example (birren 1969). the psychology of the painter requires the division of the circle into three and in six 1/6 is a number more akin to the circle than 1/8)". (klee 1956). klee's criticism of the limits of a purely technicalchemical orientation that "quietly neglects all transparent mixtures (veils)", and that shows a "complete ignorance of the relativity of chromatic values", thus becomes evident and takes shape. on the basis of this, the assumption of "harmonizing" by means of a tonality of equal value is considered reductive, since it would mean "renouncing all psychic richness" thus visualized in the tone variations limiting the artist's own freedom. it would mean, in essence, not rendering the "gradations, from the smallest movement to the rich flowering of chromatic polyphony" (klee 1956). to confirm klee's position against that of ostwald, it should be remembered that, by illustrating his theory of colour, the swiss painter reiterates that he instead drew on theories of artists, which he explicitly recalls: "i want to try to tell you something useful about colour. i don't just base myself on my research, but i take ideas from others, men of science and not, with a light heart, to give them back to you. to name a few, i remember goethe, philipp otto runge, delacroix, kandinsky". on the contrary, the reference to some "men of science" is more general, but it is not by chance that wilhelm ostwald is mentioned among them. regarding his theory, klee writes, in a letter to hans hildebrandt: "what most artists have in common, the aversion of color as a science, became understandable to me when, a short time ago, i read ostwald's theory of colors. but i wanted to take some time to see if i could get something good out of it. instead, i only managed to extract a few curiosities. first of all, the pedestrian claim that acoustic science has stimulated music production. so, the reference to helmholtz-ostwald parallelism in their negative relationship to the arts would be quite correct. but that's not what they allude to. scientists often find something childish in the arts. but in this case the positions are reversed. puerili are also other things, for example the conception of a potsdam square in which cars circulate honking their horn with a chord of do sharp. that could be two theories for a model: the “querelle” between klee and ostwald 66 color culture and science journal vol. 11 (2) doi: 10.23738/ccsj.110207 funny, apart from the harmful practice whereby this uniform chord, this sound image without dissonances would be musical. his ideas on the harmonic chord of colours are also devoid of dissonances: the result is sounds comparable to the jodler and the gstanzerl. because it is an old story that beauty combined with beauty gives an insipid result. very strange also the idea that the temperate chord in music is the work of science. i can only see it as a practical help. an analogous help is the scale of the chemical industry of the colors. of course, we've been using it for a long time, but we don't need a colour theory at all. all the infinite mixtures never produce schweinfurt green, a saturated red and a cobalt violet. in our country a dark yellow is never mixed with black because otherwise it gives the green. in addition, the chemistry of colours quietly overlooks all transparent mixtures (glazes). not to mention the complete ignorance of the relativity of the chromatic values. to believe that the possibility of harmonizing by means of a shade of equal value must become a general rule is to renounce all psychic richness. thank you very much!" (klee 1956). in the bauhaus years (but also in the decades that followed), like klee and kandinsky, johannes itten also rejected ostwald's double cone approach: "when he establishes the equation 'harmony = order' he contests and gives the circle of colour of equal shade and the triangle of colour of similar value (saturation) as an example of order, he neglects the psychological laws of simultaneity and posthumous effect", demonstrating how convinced he was of the need for an interpretation of colour in a strongly psychological key, in this case gestalt (marotta 1999). more generally, the attention even if indispensable to the theoretical contributions matured at bauhaus and privileged here, must not overlook more experimental findings and outcomes of the chromatic theories themselves. alongside the already mentioned applications of klee and albers (albers 1962) (in the field of glass painting) or of kandinsky (for fresco techniques), numerous experiences have developed from the same theories, inside and outside the laboratories of the school. here we can remember the examples in the atelier of decoration for interior architecture, directed by hinnerk scheper, or the architectures in the manifestations of the neoplastic movement decomposed according to chromatic planes, by theo van doesburg and gerrit thomas rietveld, by pieter oud and ludwig mies van der rohe. or, architectural projects inspired by the same principles, by herbert bayer, alfred arndt, farkas molnàr. the same applies to the textile workshops (with the contribution and work of artists such as anni albers and günta stoltz), graphics (with figures such as herbert bayer) and children's games: the toys developed at the bauhaus, not being a perfect imitation of objects from the adult world, were to stimulate the child's imagination, allowing him to set in motion the infinite possibilities of composition and free reproduction of objects. ludwig hirschfeld-mack, with his colorful spinning top, particularly enhances the educational aspect. wingler notes in particular: "on the rotating spinning top, cardboard discs with printed segments in different colours or eccentric coloured circles could be thrown onto the pole. the rotation movement gave rise to an optical mixture of colours. this demonstrated, among other things, goethe's, schopenhauer's and bezold's theories of colour” (wingler 1962, zevi 1974). 3. klee and ostwald. comparison of chromatic theories we can once again confirm that at the bauhaus itten's thought (itten 1962) contrary to ostwald's theories was shared with similar intensity by klee: although as a young man, in 1904, he was one of the few artists to express enthusiasm for wilhelm malerbriefe's manual (letters to a painter), calling it "an excellent scientific treatment of all technical subjects", later his opinions changed radically, as we have already mentioned, in the aforementioned letter to hildebrandt (klee 1956, cherchi 1978). 3.1 wilhelm ostwald. the fate of a chemist, nobel laureate and artist as we have already mentioned, the theoretical principles that ostwald (marotta 1999) enunciates, carrying out chemical experiments and expressing important considerations on colors, have been strongly opposed by artists such as itten and klee. the double cone, his model of color, created it seems between 1915 and 1919 has a vertical axis, on which is the scale of grays (from white to black) and the central section (equator) on the plane of intersection of the two cones, on which is placed the chromatic circle. this visualization stems from his conviction that the colours included in the circle of pure colours, when mixed with white or black, differ little from each other. after graduating from dorpat university, he taught at the riga polytechnic in 1881, at the university of leipzig in 1887 and then in 1898 became director of the institute of electrochemistry in the same city. he is best known for his work on electrolytes and catalysis. in 1888 he applied the law of mass action to the ionization of electrolytes, discovering the law of dilution that bears his name and that will give a decisive impulse to the progress of this field of research; the first law allows to calculate the constant dissociation of an acid or a weak base through the measurement of the conductivity of their solutions; the second states that when a liquid in the cooling phase can, two theories for a model: the “querelle” between klee and ostwald 67 color culture and science journal vol. 11 (2) doi: 10.23738/ccsj.110207 by solidifying, assume a stable or metastable form, it generally solidifies in the first time in the metastable form. in 1907 he developed the industrial preparation of nitric acid by catalytic oxidation of ammonia (marotta 1999). his studies on catalysis earned him the nobel prize for chemistry in 1909. he also deals with topics of a philosophical nature, interests that led him to find the "annalen der naturphilosophie". he was one of the first ardent advocates of energyism, a doctrine that, in opposition to mechanical materialism, denied the need to base physics on the idea of matter and on atomistic hypothesis in particular, considering the concept of energy as fundamental, to which the explanation of every physical phenomenon can be traced. ostwald considers energy as a sort of metaphysics where energy takes on the role of first principle, source of all the forces of nature. the overcoming of scientific materialism (die ueberwindung des wissenschaftlichen materialismus, leipzig 1895), opens a bitter controversy that will long oppose materialists and energetists. however, already at the beginning of the new century, his conceptions appeared to be surpassed by the numerous confirmations that the atomistic hypothesis received in every sector of physics. in his manual of colours (die farbenfibel) (ostwald 1922) he expresses himself as follows: "experience teaches that certain juxtapositions of colours produce a pleasant effect, others an unpleasant or indifferent effect. the problem of why arises. the answer is: colors that are in a precise and regulated reciprocal relationship, that is, in an order, produce a pleasant effect. if this is missing, the colours appear unpleasant or indifferent. the groups of colours that produce a pleasant effect are called harmonic and we can therefore establish the fundamental principle: harmony = order. in order to find all possible forms of harmony we must explore all possible ways of sorting the colors. the simpler the order is, the more evident and obvious is the harmony. of all the orders, two seem to us to be fundamental, that is, the disc of equivalent colours (having the same brightness or darkness) and the triangle of identical tonal values (that is, the combinations of a colour with white or black). discs produce harmonies of different tones, triangles, harmonies of the same value" (marotta 1999). 3.2 paul klee, the destiny of a multiform and multifaceted artist in klee's investigations (marotta 1999) one of the themes of interest is the manifestation of visual forms in the plane (dynamically conceived and expressed), also in relation to spatial dimensions. the forms that make up an image have a different incidence, depending on their brightness, size and chromatic character and can (must) be organized in a balanced composition. in particular, his discovery of colour took place on the occasion of his trip to tunis in 1914 (a circumstance partly overestimated by many critics), as evidenced by the notes in his diary where he wrote, among other things: "we have become one with colour". in 1922 he created what he called the canon of totality (fig. 2) inspired in some way by the circle generated by the section of the runge sphere, with the intermediate and universal grey and the two poles white and black. klee tries to visualize the dynamic quality of colour through a spiral movement his favourite form that transmits with its development the energy of colour on the circumference, while diametrically the chromatic pairs are harmonized by the grey that "fluctuates" in the centre. born into a family of musicians, from whom he inherited a great passion for music and in particular for the violin, after high school in bern, klee studied painting for three years at the academy in munich. in these years he received a teaching based on the rigor of the hatching and on a realism respectful of the proportions. he studied anatomy and art history and already in 1902-03 he expressed a highly plastic, grotesquely caricatured style. around 1909 he moved on to a graphic phase characterised by a nervous touch, accentuated dynamism and the subtlety of the figures. the first exhibitions in switzerland and munich date from this period. after 1912, he devoted himself to the reworking of french models such as those of cézanne and delaunay, frequenting exponents of the blaue reiter. in 1914 he made his trip to tunisia: the suggestions and naturalistic notes that he drew from them helped to direct him towards daring lighting solutions. the works of this period are characterized by programmatically twodimensional formal configurations, frequent symbolic allusions and the introduction of a lyrical, ironic, humorous note in the title of the paintings. until after 1920, subtle articulations of lines, scribbles, representing men or animals pervaded by a violent dynamic tension, predominate in his works. increasingly he uses combinations of parallel lines, with circumferences that recall wheels connected to transmission belts, arrows, heart-shaped motifs, ships and finally, horizontal lines on which the structures seem almost strung. a particular meaning also has the presence of numbers, letters or words: a module of cubist collages, which in klee constitute the link between the spirituality of thought and its realization rationally controlled, plastic, characterizing the pictorial invention as a poetic expression. this formal freedom will be accompanied in oils, watercolours and tempera by a definitive conquest of the chromatic dimension. from the time he travelled to tunis, klee began to coordinate delicately luminous coloured surfaces, before using colour as an element of a fantastic narrative: dark, often dark fields, from which clear luminous motifs or graffiti drawings are detached. around two theories for a model: the “querelle” between klee and ostwald 68 color culture and science journal vol. 11 (2) doi: 10.23738/ccsj.110207 the twenties, klee experimented with a very different and articulated use of colour, applied in relation to the greater or lesser weight of the contours, with their dynamics and expressive force: a choice certainly linked to the didactic activity carried out at the bauhaus. this new conception of colour is accompanied by the writing of theoretical writings, through which klee intends to communicate his vision of art. in 1924, during a lecture at the kunstverein in jena, he explained that the different functions in the different realms of nature lead to vital irregularities, reiterating (in accordance with the principles of gestalt) that the artist must deal with the dimensions of mass (line), weight (tonality) and quality (color), not verisimilitude and must aim not at an external model, but at the original theme, the principle of creation, where the key to everything lies. on the other hand, in a note klee argued that the figure is a living being, it is nature, because his theory of figuration (gestaldtung) deals with the ways that lead to form. saying: "theory of formation" is unusual, therefore, compared to form, figure (gestalt) expresses something more alive. the figure is a form based on vital functions and these functions are of a spiritual nature, their basis is the need for expression. to pass from a form to a figure he maintains creative force is necessary, which therefore cannot be defined: there is matter and reason". in addition to this, the choice of means is important: over the material means (wood, metals, glass) it is preferable to use the ideal means (line, chiaroscuro, color): writing and image (klee 1956). writing and figuration are basically all one to abstract and synthesize reality and not to represent it. for this reason, figuration is linked to movement: the point moves, and a line derives from it as the first dimension; the line obtained, by moving, forms the two-dimensional plane. the collision of the planes results in a threedimensional solid body. klee, who is a musician, tries to set painting in analogy with harmonic systems, elaborating the elements of his themes like a specialist in the field, with notes, motifs, themes and modulations and despite supporting the need for a clear separation between the arts, evident are, especially in initial experiences, many points of contact with music. the very name of "canon of totality", attributed to his chromatic model, proves the close and complex relationship that the artist grasps between color and music, in a broader and more synaesthetic conception of "circularity and complementarity" of the various forms of art. thus, we find works with a clear polyphonic or monophonic character, continuous melodies, based on uninterrupted lines, ascending and descending rhythms, tonal and atonal relations, etc. numerous trips and exhibitions, including in the united states, preceded his appointment as professor at the state academy of düsseldorf in 1931. during this period, his production saw the succession of various stylistic tendencies: compositions with parallel lines that thickened to the point of overlapping, references to compositional principles of a musical nature, with the use of gradations, planes on which colour stains were regularly distributed, large luminous fields crossed by parallel or converging lines. these abstract figures are sometimes superimposed on figurative fragments or human figures. from 1937 his style took on dark, dramatic tones, his poetic message was veined with suffering and pessimism; on a background (monochrome or polychrome) dense black brushstrokes appear and black are also the features that surround the colored areas. klee is deeply anxious about the events in nazi germany, which also hurt him on a personal level. klee's work, with its inimitable variety of expressions, occupies a central position in the artistic panorama of the twentieth century. it represents the affirmation of the creative freedom of an abstract language, in many respects similar to that of music and poetry. klee's painting, sometimes reserved, soft, imbued with humour, often painful, visualizes the different spiritual and artistic tensions that characterize the existential dimension of the twentieth century. 4. developments, insights, denials as is well known, contradicting his previous obstinacy, from 1925 kandinskij changed his mind, supporting ostwald's theories, while gropius and the designers, who until then had been more attentive and sensitive to technological aspects, also considered them benevolently. wilhelm's chromatic theory in an unusual way compared to the custom of the contemporary authors placed green among the primary ones, together with red, yellow and blue. the colour wheel shown in his sillabario dei colori (1916) assigns no less than nine of the twenty-four subdivisions to green; he did not discuss the concept of green as a "secondary" mixture of blue and yellow, but rather considered and in a "mediated" position with respect to exclusively material and technical parameters green as perceptively autonomous: a recognition of goethe's psychological dimension of tributary colour. in turn, in fact, the chemist had derived his theories from the viennese gestalt psychologist ewald hering (marotta 1999), who hypothesized three sets of "antagonistic colors", in great similarity with the goethean oppositional categories. however, among the salient aspects of ostwald's chromatic thought, the role assigned to the grey component in colour emerges with the proposal of the concept of "brilliance" for the range of greys in coloured space. in his chromatic sphere, otto runge had tried to extend the goethian circle of colours, lying on a plane, through a perpendicular axis, with the development (in the two theories for a model: the “querelle” between klee and ostwald 69 color culture and science journal vol. 11 (2) doi: 10.23738/ccsj.110207 space conceived in three dimensions) of tones, from the black pole to the white pole in the opposite pole, without considering the need to represent variations for the grey placed at the centre of the sphere. the scientist was struck when, at harvard in 1905, he had the opportunity to confront albert munsell, who had a three-dimensional idea of the chromatic system. the chemist wanted to translate this mental model into a series of easily recognizable principles that could guide the artists, allowing them to obtain a harmonic chromatic composition. thus, he developed a perceptual scale of gray tones that varied gradually and uniformly. these gradations were derived from a mathematical equation between the progressive percentages of black and white; ostwald then applied the resulting range of greys to each of the shades of his twenty-four-part colour wheel, convinced that chromatic harmony arose from the application of colours whose values with relative grey components were compensated for. this was the central idea exposed in the sillabario dei colori, which klee irrevocably rejected. on the contrary, the artist recommends that painters "cut" the colors with white to harmonically balance the colors. the nobel prize winner, in a convinced and persistent way, continued the battle to defend his ideas. thanks to his scientific expertise, he applied his theory effectively to the material aspects of the pigments from which he obtained the colours, and his role as consultant to the german paint industry enabled him to apply it to commercial products. in 1914 he organised an exhibition of industrial paints and dyes on behalf of the deutsche werkbund, the german association for art and design. in 1919 he opened a series of technical conferences on colour in stuttgart, the tradition of which continues to this day. if we wanted to give an example of the differences, in particular, between the concepts that differ most from ostwald's convictions, in paul klee's thought there is the "dynamic" thought of the "peripheral chromatic movement" (klee 1956): an infinite movement that takes place along the circumference and in contrast to the pendular movement that takes place along the diameter. here the colors continuously pass into each other, there are no interruptions and every beginning is also the end. each color starts from its nothingness, that is from the culmination of the near color, first slowly and then more and more growing until it touches its own culmination; it then begins to slowly decrease, toward its nothingness, that is toward the culmination of the other adjacent color. "if we consider, for example, the color red, we will not be wrong by fixing its width to two thirds of the circumference. there is a red that gives in yellow (the so-called warm red) and a red that gives nerazzurro (the so-called cold red). but both of them represent, compared to pure red, a weakening. it must therefore be noted that red increases from one side or the other and this increase from two sides naturally leads to a climax, to a climax where red reaches its maximum height. three points can then be established on the circumference: the red peak, the hot end of the red and the cold end of the red. these three points divide the circumference into a red line that measures two thirds, and a line without red that measures one third and is opposite to the red peak. in the same way the amplitude of yellow and blue can be determined" (klee 1956). since the early decades of the twentieth century, ostwald had strongly advocated his theories, obtaining greater consensus and support among the european artists of the time, both as a concrete basis for their work and as an object of criticism. among other things, he took on a charismatic role among the dutch painters of de stijl, such as theo van doesburg, jacobus johannes, oud and piet mondrian, although the latter, who was very attentive to the question of primary colours, struggled to understand what ostwald's theory required in order to use colour correctly: should green be included or not? 5. conclusions in addition to describing cultural matrices, parameters and essential characteristics of the models examined, of particular interest is the scope of the applications already put in place of the models, or possible future developments, also connected to new methodologies (such as virtual and digital) in the color project, up to the experiments in concrete and material production. following a methodological approach already developed and tested, the work will in the future tend towards a threedimensional graphic interpretation and representation that from a cultural and philological point of view can be a tool for analysis and interrogation of sources. specifically, quantitative elaborations should start from other assumptions to produce results of some interest. in this regard, it is useful to remember that it is always essential to make an explicit and reasoned declaration of the methodological approaches and parameters used, considered the most appropriate for the purposes of scientific investigations. the visualization, also dynamic, of the single models, including the constituent parameters, constitutes a privileged laboratory for specialized scientific investigations, in which the dynamization will be able to render more effective the temporal sequences between the various models, also of different authors, in order to two theories for a model: the “querelle” between klee and ostwald 70 color culture and science journal vol. 11 (2) doi: 10.23738/ccsj.110207 highlight and confirm their developments through the parameters, as well as to better narrate the modifications in time, for example of similar models, between analogies and differences. this is especially true if we consider them both in their original version and in their various reworkings, both in the related theories (with purely speculative aspects) and in their representations with more exquisitely formal and communicative characters (fig. 1). klee ostwald regulated freedom free rule "free" "scientific" "dynamic" "regulatory, regulatory, programmatic" "sensory, multisensory," "visual, perceptual," "gestaltic" harmony comes from the order of science "synaesthetic" "energetist" "symbolic" "idealist" fig. 1. the "reverse oxymoron" represented in the table summarizes in the first instance the possible categories to evaluate convergences and differences between klee and ostwald. fig. 2. paul klee, the canon of totality, 1922. source: anna marotta, policroma […], p. 131. fig. 3. wilhelm ostwald, double cone, 1915-1919. source: anna marotta, polychrome [...], p. 125. two theories for a model: the “querelle” between klee and ostwald 71 color culture and science journal vol. 11 (2) doi: 10.23738/ccsj.110207 fig. 4. wilhelm ostwald, die farbenfibel fig. 5. wilhelm ostwald, amateur artist and nobel prize winner for chemistry. fig. 6. paul klee, the fixing of pigments on the chromatic disc, 1922. source: paul klee. theory of form and figuration, milan, 1959, fig. 1, p. 509. two theories for a model: the “querelle” between klee and ostwald 72 color culture and science journal vol. 11 (2) doi: 10.23738/ccsj.110207 fig. 7. visualizations of possible chromatic comparisons, also in relation to brightness. in particular, for the chromatic pairs klee paid attention to the "false" or "authentic" ones, such as the complementary colours red and green. source: paul klee. theory of form and figuration, milan, 1959, fig. 1, p. 472. 6. funding source declaration this research did not receive any specific grant from funding agencies in the public, commercial, or not-forprofit sectors. 7. conflict of interest the author declares, that nothing has affected her objectivity or independence in the production of this work. there are no actual or potential conflicts of interest, including financial, personal or other relationships with other people or organizations. 8. short biography of the author anna marotta architect, ph.d, full professor in representation at the department of architecture and design (dad) of politecnico di torino. member of the doctoral college in architectural and landscape heritage. she teaches disciplines related to drawing and representation fields, including visual communication and semiotics, laboratory of drawing and architectural survey, atelier of representation and project, drawing from the true and the imaginary. since 2012 she is a member of the scientific committee of the gruppo del colore and she is a member of the presidential committee of the associazione nazionale colore. he directs the "culture of vision" series, for the publisher aracne. references marotta a. (1999) ‘policroma, dalle teorie comparate al progetto del colore’, torino: celid. marotta a., vitali m. (2017) ‘la modellazione tridimensionale come espansione concettuale dei modelli del colore‘, napoli: xiii conferenza del colore 2017. geelhaar c. (1972) ‘paul klee und das bauhaus‘, köln: dumond schauberg. cherchi p. (1978) ‘paul klee teorico‘, bari: de donato klee p. (1920) ‘confessione creativa‘, schöpferische konfession, norderstedt: bod buchshop. klee p. (1956) ‘das bildenrische deuken. schriften zur form und gestaltungslehre‘, basel: schwabe & co. ed. italiana: dorfles g. (acura di), teorie della forma e della figurazione, feltrinelli, milano 1959. ostwald w. (1922) ‘die farbenfibel, verlag unesma gmbh birren f. (1969) ‘the color primer: a basic treatise on the color system of wilhelm ostwald‘ new york: van nostrand reinhold. wingler h. m. (1962) ‘das bauhaus. weimar-dessau-berlin 1919-1933‘ bramsche: rasch & co. verlag. ed. italiana: f. dal co (a cura di), il bauhaus. weimar-dessau-berlino. 1919-1933, feltrinelli, milano 1972, p. 312. zevi b. (1974) ‘poetica dell’architettura neoplastica’ torino: einaudi. itten j. (1962) ‘kunst der farbe‘ ravensburg: otto maier. albers j. (1962) ‘interaction of color‘, new haven: yale university press. color culture and science cultura e scienza del colore ccsj volume 11 number 2 2019 issn 2384-9568 color culture and science (ccsj) cultura e scienza del colore jcolore.gruppodelcolore.it issn 2384-9568 doi: 10.23738/ccsj.00 ance e227716 road: the directory of open access scholarly resources registrazione presso il tribunale di milano n. 233: 24/06/2014 volume 11, number 2, dec. 2019, doi 10.23738/ccsj.110200 publisher gruppo del colore – associazione italiana colore www.gruppodelcolore.org registered office: piazza carlo caneva, 4 20154 milan (it) peer review process all articles submitted to the " color culture and science journal are peer-reviewed according to the following procedure: first review level the associate editors evaluate each article in order to determine if the topic and content are of interest to the journal. once the article passes the initial review, the associate editors select several referees in the editorial board based on their expertise in a particular subject area or topic. second review level each article is reviewed by two or three referees and submitted to a double-blind peer review process where both the authors and the reviewers are kept anonymous. referees are asked to evaluate the manuscript based on the following criteria:  originality  relevance to journal’s aims and scope  technical merit and/or validity  soundness of methodology  completeness of the reported work  conclusions supported by the data  correct acknowledgment of the work of others through reference  effectiveness of the manuscript (organization and writing)  clarity of tables, graphs, and illustrations  importance to color researchers  relevance to color practices if the article is accepted with major revisions by the referees, the author(s) are asked to improve the article according to the suggestions of the referees. the revised article will then be submitted to a further review. after collecting the referees' reports, the associate editors make a recommendation on the acceptability of the article to the editor-in-chief. editorial board members john barbur (city university london, uk) giovanni bartolozzi (ifac-cnr, it) laura bellia (università di napoli federico ii, it) berit bergstrom (ncs colour ab, se) giulio bertagna (b&b colordesign, it) janet best (natific, uk) aldo bottoli (b&b colordesign, it) josé luis caivano (universidad de buenos aires, ar) patrick callet (école centrale paris, fr) jean-luc capron (université catholique de louvain, be) daria casciani (politecnico di milano, it) vien cheung (university of leeds, uk) paula csillag (espm university, br) osvaldo da pos (università degli studi di padova, it) hélène declermont-gallernade (chanel parfum beauté, fr) reiner eschbach (xerox, usa) alessandro farini (ino-cnr, it) christine fernandez-maloigne (university of poitiers, fr) renato figini (konica-minolta sensing europe, eu) raffaella fontana (ino-cnr, it) davide gadia (università degli studi di milano, it) marco gaiani (alma mater studiorum università di bologna, it) robert hirschler (serviço nacional de aprendizagem industrial, br) takahiko horiuchi (chiba university, jp) sandra krasovec (fashion institute of technology, usa) agata kwiatkowska-lubańska (academy of fine arts, kraków, pl) francisco imai (canon, usa) lia luzzatto (color and colors, it) kevin mansfield (ucl, uk) veronica marchiafava (gdc-associazione italiana colore, it) gabriel marcu (apple, usa) anna marotta (politecnico di torino, it) manuel melgosa (universidad de granada, es) anna grazia mignani (ifac-cnr, it) annie mollard-desfour (cnrs, fr) maria luisa musso (universidad de buenos aires, ra) galina paramei (liverpool hope university, uk) laurence pauliac (historienne de l’art et de l’architecture, paris, fr) silvia piardi (politecnico di milano, it) marcello picollo (ifac-cnr, it) renata pompas (afol milano-moda, it) boris pretzel (victoria & albert museum, uk) noel richard (university of poitiers, fr) katia ripamonti (cambridge research system, uk) alessandro rizzi (università degli studi di milano, it) maurizio rossi (politecnico di milano, it) jodi l. sandford (università di perugia, it) raimondo schettini (università degli studi di milano bicocca, it) verena m. schindler (chair aic s.g. environmental colour design, ch) gabriele simone (renesas electronics europe gmbh, de) andrea siniscalco (politecnico di milano, it) ferenc szabó (university of pannonia, hu) mari uusküla (tallinn university, ee) francesca valan (studio valan, it) ralf weber (dresden university, de) stephen westland (university of leeds, uk) alexander wilkie (charles university in prague, cz) associate editors josé luis caivano (universidad de buenos aires, ar) vien cheung (university of leeds, uk) marco gaiani (alma mater studiorum università di bologna, it) robert hirschler (serviço nacional de aprendizagem industrial, br) agata kwiatkowska-lubańska (academy of fine arts, kraków, pl) marcello picollo (ifac-cnr, it) verena m. schindler (chair aic s.g. environmental colour design, ch) renzo shamey (nc state university, usa) francesca valan (studio valan, it) deputy editor alessandro rizzi (università degli studi di milano, it) editor-in-chief maurizio rossi (politecnico di milano, it) 3 color culture and science journal vol. 11 (2) issn 2384-9568 table of contents editorial 5 maurizio rossi the colored chemistry 7 david ajò, giuseppe elettivo, federica fenzi, stella nunziante cesaro, sabrina tegani doi: 10.23738/ccsj.110201 the colours of the ancient greek architecture 14 rossana netti doi: 10.23738/ccsj.110202 primary colors as a source of possible misconceptions: an insight into teaching and learning about color 25 berta martini, monica tombolato, rossella d’ugo doi: 10.23738/ccsj.110203 chromatic values in pablo picasso’s early work: a comparison of hues in “science and charity” (1897) and its three oil sketches 34 marcello picollo, costanza cucci, lorenzo stefani, reyes jiménez-garnica, laura fuster-lópez, anna vila doi: 10.23738/ccsj.110204 education about colour: a look at some authors from the 19th and 20th centuries in italy: corrado ricci, maria montessori and giuseppina pizzigoni 43 franca zuccoli doi: 10.23738/ccsj.110205 from dots to atoms: “light and color’’ techniques in fifteenth and sixteenth centuries’ painting 49 carmen di meo doi: 10.23738/ccsj.110206 4 color culture and science journal vol. 11 (2) issn 2384-9568 two theories for a model: the “querelle” between klee and ostwald 63 anna marotta doi: 10.23738/ccsj.110207 under the lens of isle: leonardo da vinci’s "landscape" drawing analysed by colourimetry 73 marco gaiani, fabrizio ivan apollonio doi: 10.23738/ccsj.110208 a case study on light and colour for monuments and cultural assets 82 andrea siniscalco doi: 10.23738/ccsj.110209 evaluation of the perceived colour difference under different lighting for museum applications 90 alice plutino, laura grechi, alessandro rizzi doi: 10.23738/ccsj.110210 coloumn review: nature & colour new perspectives on dyeing 98 renata pompas 5 color culture and science journal vol. 11 (2) issn 2384-9568 editorial dear readers, with vol 11 n. 2 we close a six-year cycle and go on for a future of consolidation of our journal in the next year. as announced, the journal web management is now available online via the open journal system and doi database has been updated accordingly, given that the old joomla site has been discontinued and the urls of all the previously published papers have been changed. this will allow a better indexing of the published articles and will guarantee the compatibility with open archives initiative protocol for metadata harvesting (oai-pmh). since 2014 we have published 11 volumes for a total of 12 issues, adopting from 2019 the new numbering which publishes one volume per year with two or more issues for each year. since 2015 we have applied the double blind peer review and since 2016 we have applied the digital object identifier system. this has been possible thanks to the voluntary support of the members of the "associazione italiana colore" who work in the editorial committee, thanks to the members of the editorial board, thanks to the deputy editor alessandro rizzi and the president of our association marcello picollo who, from the beginning of his mandate, has guaranteed support to the ccsj. a special thanks goes to filippo cherubini of ifac-cnr who oversaw the migration of our archive to the open journal system, to veronica marchiafava, the secretary of our association, for the management of doi database and to andrea sinicalco, the vicepresident of our association, for the graphic support for the new layout. after six year of publishing of the ccsj it is also useful to recall the importance of the concept of double open access under which our journal is managed and published: the journal is completely free for both readers and authors. since 2019 we have also had the significant support of the associate editors and from this issue we also have a new entry, agata kwiatkowska-lubańska of the academy of fine arts of kraków (poland), who will support the peer review process of the papers in the area of color and design: furniture, design, fashion, textiles, cosmetics, food design, museography. the peculiarity of our journal, also written in the statute of our publisher, the associazione italiana colore, is to collect papers on color and related areas in a multidisciplinary way. this basically means that in our peer review process we could have papers ranging from the science of colorimetry to the culture of color in the history of art. moreover, these papers have very different styles and ways of writing, as diverse is the group of the peer reviewers that constitutes our editorial board. this multidisciplinarity is a richness for the mind, for color science and for color culture, and i will not get tired of repeating it to all those who collaborate in the journal or at the conferenza del colore, and specially to those few people who tend cyclically and obstinately to forget it. december, 2019 the editor-in-chief maurizio rossi full professor of lighting design and design methods politecnico di milano 6 color culture and science journal vol. 11 (2) issn 2384-9568 this page intentionally left blank cultura e scienza del colore color culture and science 902/14 | cultura e scienza del colore color culture and science franca zuccoli franca.zuccoli@unimib.it dip. scienze umane per la formazione, università degli studi di milano bicocca a scuola di colore. pensieri e parole di insegnanti e di bambini 1. introduzione il colore è un ingrediente fondamentale nella vita dei bambini, costituisce uno degli elementi imprescindibili nei loro disegni oltre che nei dipinti, la sua preferenza influenza, fin dalla più tenera età, la permanenza dello sguardo [1], indirizzando in seguito la scelta di oggetti, giocattoli, vestiti, come attestano numerose ricerche sulle preferenze cromatiche espresse dai bambini, in base all’età, al genere, o all’appartenenza a gruppi specifici, che non giungono però a un’univocità di risultati [2]. nella scuola questo elemento così significativo trova sovente una sua messa a tema nelle attività proposte dai docenti e nell’individuazione degli arredi da utilizzare, anche se ciò non avviene in modo sempre totalmente consapevole. esiste una letteratura su questi argomenti, insieme ad alcune documentazione di esperienze sull’insegnamento di tecniche d’uso del colore; poco esplorato è invece un utilizzo del colore ad ampio spettro, inteso come contenuto culturale, che superi le barriere disciplinari, analizzando: il tema dei significati attribuiti, l’uso personale documentato, le riflessioni sulle proposte fatte. questo studio vuole iniziare a delineare una prima panoramica sul rapporto tra scuola e colore, su come cioè questo tema venga affrontato e proposto nelle sezioni e nelle classi, grazie ad un’indagine su due fronti. nelle prima parte del lavoro viene analizzato quello che la legislazione scolastica nel tempo ha previsto su questo argomento, per le scuole dell’infanzia e primarie, insieme a quello che una parte della letteratura ci prospetta nei confronti delle idee e delle azioni dei bambini riguardo al colore. a partire da questo primo approfondimento, nella seconda parte ci si addentra nella scuola attuale, grazie a un’indagine esplorativa, anche se parziale per numero di analisi, rivolta ai futuri insegnanti e ai bambini, per sondare quello che pensano su questa tematica, scrutando quali idee abbiano del colore, quali preferenze manifestino e per i docenti quali possibilità operative ritengano possano esserci all’interno della scuola. questo per consentire, nell’immediato futuro, un ulteriore passaggio, nello sviluppo di un’indagine sul campo a più largo raggio, avendo già tematizzato alcune ipotesi. 2. ipotesi percettive sul colore e programmi scolastici: cenni storici da molto tempo studiosi afferenti a diverse discipline si sono interrogati sul rapporto che i bambini hanno con i colori, in primo luogo analizzando la tipologia della loro percezione. le ipotesi formulate sono state diversificate, ma è interessante, per questa trattazione, riportare quella di corrado ricci [3], eminente storico e critico d’arte che tra i primi in italia si è occupato della relazione esistente tra bambini e arte e in alcune pagine del suo trattato ha investigato anche il loro rapporto con il colore, fotografando l’evoluzione del pensiero a lui contemporaneo. alcuni autori (william gladstone, ad esempio) pensavano in quel periodo che gli antichi vedessero un numero inferiore di colori rispetto a noi, e che questa particolarità fosse estendibile anche ai selvaggi e ai bambini. hugo magnus, william thierry preyer, tra gli altri, giungevano ad affermare come i colori visti dai fanciulli fossero all’inizio esclusivamente il giallo e il rosso, solo in un secondo momento il verde e l’azzurro, peraltro confuso con il grigio. queste posizioni non convincevano il ricci, che così sentenziava: “certamente bisogna educare il senso cromatico dei bimbi come si educa la loro mano al buon disegno. non perché sia esatto ch’essi non vedano i colori, ma perché trovino una ragionevole rispondenza armonica col vero. perocché, come prima veggono benissimo le cose e non sanno ritrarre coi segni, così veggono benissimo i colori e non sanno e non si preoccupano di trovarli nella tavolozza.”[4] al termine della pagina giungeva a chiedere a maestri e genitori di indirizzare i bambini verso l’osservazione della realtà e la correttezza riproduttiva, potenziando l’attenzione mirata in particolare sulla tonalità delle tinte perché “[...] molti bambini hanno la percezione dei colori, ma spesso spostata e stonata.”[5] ecco espressa una posizione che, a partire dal 1887, ha influenzato pratiche didattiche riferite all’educazione artistica, l’idea cioè che seppure la percezione potesse essere corretta e non deficitaria anche nei bambini, come alcuni 10 cultura e scienza del colore color culture and science | 02/14 studiosi ipotizzavano, essa andasse esercitata, addestrata attraverso un’osservazione finalizzata della realtà per potenziare la capacità riproduttiva, l’unica prevista, e un uso dunque esclusivamente mimetico dell’immagine prodotta dai bambini e quindi anche dei colori a questa abbinata. di questo troviamo traccia nei programmi scolastici per la scuola dell’infanzia e per la scuola primaria [6] in italia dal 1914 (programmi credaro) ai giorni nostri, di cui qui è possibile riferire solo un rapido excursus, necessario per permetterci di capire quale sia la base storica sulla quale le attuali proposte trovano il fondamento. nel 1914 nei programmi per gli asili infantili e i giardini d’infanzia (r. d. 4 gennaio 1914, n. 27) si parla di “esercizi degli organi sensori”, da realizzare in forma di giochi brevissimi e graduati con oggetti naturali e artificiali presenti in classe, tra le varie sensazioni educabili in penultima posizione dopo sensazioni termiche, tattili, muscolari, del gusto, dell’olfatto, prima dell’udito vi sono “le sensazioni della vista (colore, forma, dimensioni, distanze, ecc)”. sempre riferite alle occupazioni dette sedentarie vi è “il disegno libero” in cui si propone il disegno fröbeliano nel reticolo, senza reticolo e “l’uso delle matite colorate per colorire stampine e disegni.”. nel successivo paragrafo “l’immaginazione e il gusto del bambino si vedono sottolineati come mezzi indiretti ma potenti di educazione estetica, oltre la bellezza dell’ambiente, la scelta e la combinazione dei colori”. nelle indicazioni per la compilazione della carta biografica di ciascun bambino, erano previsti anche esercizi per “saggiare il senso cromatico” e quindi “l’esatta percezione dei colori” con l’utilizzo di specifiche tavole, tra cui quella cromometrica. nei programmi del 1923 (o. m. 11 novembre) si nominano i colori nell’insegnamento del disegno a partire dalla i e ii elementare prevedendo “esercizi per la distinzione dei tre colori principali: giallo, rosso, turchino” e qui il maestro doveva prendere nota dei bambini “incerti nella distinzione e gradazione” facendoli esercitare. successivamente si poteva passare al “verde, arancio e violetto, insistendo nella concezione dello scambio fra arancio e rosso e fra verde e bleu” arrivando alla “formazione della scala colorata.”. nei successivi programmi della scuola materna ed elementare (carta della scuola, 1940; programmi per la scuola materna 1943; programmi, istruzioni e modelli per le scuole elementari e materne, d. m. 9 febbraio 1945) si accenna rapidamente solo al disegno non prevedendo alcuna specifica attività relativa al colore. nei programmi didattici per la scuola elementare del 1955 (dpr 14 giugno 1955, n.503) per il primo ciclo non si nomina direttamente il colore, ma si incentiva a creare occasioni per “spontanee manifestazioni grafico e pittoriche” specificando anche i materiali e gli strumenti “matite nere e colorate, pastelli, gessetti colorati, acquarelli, carte colorate”, nel secondo ciclo il disegno si fa “spontaneo, dal vero e ornamentale”, senza indicare in alcun modo la tematica del colore. nella legge n. 444/1968 istituzione della scuola materna statale, con i successivi orientamenti (orientamenti dell’attività educativa nelle scuole materne statali, dpr 10/9/1969, n.647) si parla di “libera espressione grafico-pittorica e plastica” anche qui non vengono date indicazioni prescrittive, tranne il divieto dell’utilizzo di albi stilizzati per colorare, sono invece elencati e proposti moltissimi materiali e strumenti sottolineando che i bambini “devono potersi sporcare senza preoccupazioni; la pittura con le dita e il maneggiare la creta rispondono all’esigenza sensoriale di pasticciare con i colori […]”. si sottolinea, infine, in poche righe l’importanza di un’educazione al gusto, che si può ottenere curando l’ambiente scolastico dal punto di vista estetico, qui appaiono “elementi decorativi e ritmi di colori e di forme.” nei nuovi programmi didattici per la scuola elementare del 1985 (dpr 12 febbraio 1985) ampio spazio viene riservato all’educazione all’immagine, presentata per la prima volta come disciplina autonoma con una propria dignità, si accenna al colore tra i codici specifici previsti nelle prime righe. le proposte si articolano tra fruizione e produzione e a titolo indicativo, vengono previste numerose attività, pochissimo però viene tenuto in considerazione il colore, a cui si accenna solo per il disegno e per la fotografia. nei programmi della scuola materna del 1991 (dm del 3/06/1991) si parla esplicitamente di colore nella sezione “campi di esperienza educativa c) lo spazio, l’ordine, la misura” si parla di classificare gli oggetti anche “per forma e colore”. nelle attività grafiche, pittoriche e plastiche non ne viene fatto esplicito riferimento. nelle indicazioni nazionali per i piani di studio personalizzati delle attività educative nelle scuola dell’infanzia del 2004, nella sezione “obiettivi specifici di apprendimento” alla voce “fruizione e produzione di messaggi”, si trova “6 disegnare, dipingere, modellare, dare forme e colore all’esperienza, individualmente e in gruppo, con una varietà creativa di strumenti e di materiali, ‘lasciando traccia’ di sé.”, mentre nella scuola primaria negli obiettivi specifici per arte e immagine si parla fin dalla prima classe di “colori primari e secondari”, declinati in “usare creativamente il colore” e in “utilizzare il colore per differenziare e riconoscere gli oggetti”, per la seconda e la terza classe si prevede attenzione per “scala cromatica, coppie di colori complementari”, per la quarta e la quinta si individuano “colori simbolici”. nelle indicazioni per il curricolo (roma, 9/2007), se nella scuola dell’infanzia non viene accennata in alcun modo all’importanza del colore, e ci si riferisce ad un discorso più generale in cui vengono menzionate diverse pratiche di “pittura, manipolazione, costruzione plastica e meccanica”, nella scuola del primo ciclo, per l’area linguistico-artistico 1102/14 | cultura e scienza del colore color culture and science espressiva, viene sottolineata la necessità di “un approccio operativo di tipo laboratoriale”, dove grande spazio viene dato alla “capacità di osservare e descrivere, di leggere e comprendere le opere d’arte”, e in cui l’alunno deve apprendere “gli elementi di basa del linguaggio delle immagini (linea, colore, superficie, forma volume, composizione, ecc.)”. come abbiamo visto da questa rapida panoramica la tematica del colore non è mai stata pienamente tenuta in considerazione nei programmi che si sono susseguiti nel tempo, sia per quanto riguarda le proposte, sia per la cura degli ambienti in cui lo sviluppo dell’azione scolastica viene realizzata. laddove era presente l’indicazione si trovava declinata in due possibilità: legata alla descrizione dei colori, nominandoli, suddividendoli in gruppi d’appartenenza (primari, secondari, scale,..); oppure intesa come utilizzazione, incentivando l’uso di strumenti variegati. 3. alcune esperienze significative sul colore: un quadro teorico in contemporanea alle proposte della legislazione scolastica, già da tempo la letteratura scientifica si era interrogata sul fascino che il colore provocava e provoca ancora oggi nei bambini, prospettando molteplici approfondimenti. un primo elemento, con cui si può verificare immediatamente questa importanza, è il ruolo dei colori nei disegni e nei dipinti da loro spontaneamente realizzati, la cui scelta che non necessariamente corrisponde in modo automatico alle preferenze espresse [7]. fin dal 1960 victor lowenfeld e w. lambert brittain [8] avevano posto attenzione, oltre che all’uso del colore da parte dei bambini, allo sviluppo nel tempo della sua modalità d’utilizzo, individuando delle tappe definite: tra i 18 mesi e i 3 anni i colori non rivestivano una grande importanza, erano il gesto e il segno ad interessare il bambino in modo prioritario, la scelta era, infatti, quella di privilegiare un netto contrasto tra foglio e matita, in modo da cogliere senza incertezze la propria traccia. successivamente, tra i 4 e i 7 anni, la selezione del colore era legata alle preferenze personali; mentre tra i 7 e i 9 anni si verificava la scoperta di una relazione tra colori e oggetti e questo era tenuto presente nell’elaborazione grafico-pittorica successiva. negli studi più recenti [9] è confermata l’importanza del segno come elemento prioritario dell’interesse del bambino, ritenendo sufficiente nei primi elaborati realizzati avere un solo colore, la cui scelta, però; secondo claire golomb [10] non è casuale ma è attinente alle proprie preferenze. in un secondo momento, quando il bambino riesce a padroneggiare meglio le forme basilari, l’uso dei colori si lega al puro piacere che esso procura, senza necessariamente fondarsi su una funzione realistica, solo con il passare del tempo vengono applicate delle prime restrizioni veristiche. in questo periodo, per golomb tra i cinque e i sette anni, emerge anche un utilizzo decorativo, alternativo o concomitante alla raffigurazione naturalistica. il colore e la sua presenza diventano criterio fondamentale anche per formulare giudizi nei confronti dei disegni o i dipinti altrui [11]. proprio cogliendo queste potenzialità la scuola, nel tempo, ha messo a tema questo aspetto, ben oltre le richieste del legislatore, anche se non sempre con la dovuta consapevolezza, qui si riportano tre esperienze significative legate a due pedagogisti, francesco de bartolomeis e loris malaguzzi, e a un artista/ designer, bruno munari, che hanno progettato e monitorato alcune azioni pregnanti sulla tematica del colore. si tratta di percorsi speciali, che però consentono di approfondire la varietà delle possibilità che il colore può fornire. già nel 1990, ad esempio, francesco de bartolomeis [12] aveva posto l’attenzione sul colore come elemento fondamentale per i bambini, sostenendo che la scuola non poteva non prenderne atto, ed anzi sottolineando come dovesse renderlo oggetto di un lavoro particolare, vero e proprio protagonista di azioni educative. nella sua ricerca il pedagogista giunge nel 2003 [13] a puntualizzare come, grazie alla sua osservazione approfondita all’interno delle scuole, avesse notato che molto spesso ci si limitasse solamente a far usare ai bambini i colori così come venivano proposti nelle confezioni vendute, senza avviare alcun tipo di esplorazione. da qui partiva il suggerimento, sperimentato, di condurre un’azione didattica articolata, secondo alcuni punti fondanti: creazione di nuovi colori (miscelando primari, secondari, complementari, lavorando sui toni, ...), attenzione ai rapporti tra i colori (colori non colti in modo isolato, ma posti sempre in relazione ad altri), sperimentazione delle diverse tipologia (tempera, olio, smalto, acquarello, pastello,...), interesse nei confronti del tipo di stesura (tocchi, campiture, pennellate spesse o leggere, ...). ancor prima bruno munari, a brera nel 1977, aveva proposto ai bambini e alle scolaresche, che affollavano la pinacoteca, tra i vari laboratori, uno basato esclusivamente sul rosso, evidenziando così le potenzialità che un solo colore poteva avere, alternando, una prima azione esplorativa e produttiva a una successiva fruizione con occhi nuovi, stimolati da questa esperienza monocroma, all’interno delle sale del museo, delineando così già quelle modalità operative proprie del suo metodo. [14] al contempo nelle scuole dell’infanzia di reggio emilia, legate alla figura di loris malaguzzi, l’approccio al colore avveniva sempre con una sperimentazione molto attenta e articolata, in 12 cultura e scienza del colore color culture and science | 02/14 cui si interrelavano i lavori in sezioni e quelli nell’atelier, e dove la parte produttiva non dimenticava mai una fase sperimentale, come la ministoria “meraviglia fucsia” ci racconta, in cui bambini dai 18 ai 22 mesi osservano e giocano con un colore che si forma nell’acqua. [15] fin dall’inizio il colore era stato elemento imprescindibile anche nella progettazione delle stesse scuole, per costruire le quali: pedagogisti, genitori, insegnanti e architetti elaboravano un progetto condiviso, sia che si trattasse di una scuola da edificare ex-novo, sia che dovesse collocarsi in un edificio preesistente. da quelle prime esperienze le sperimentazioni reggiane si sono costantemente accresciute e articolate, arrivando a contaminare più settori disciplinari, come ci dimostrano i lavori dell’atelier raggio di luce, reggio children 2006-2011.[16] qui il colore e la luce sono divenute occasioni per proporre un approccio innovativo non solo all’arte, ma soprattutto alla scienza, oltre che un nuovo modo per guardare la realtà delle cose. bambini e adulti sono, infatti, stimolati a interrogarsi, a formulare delle ipotesi e teorie provvisorie, che necessitano di una messa a punto costante, attraversando un processo di verifica sperimentale, che utilizza esperienze tattili, percettive, corporee. a conclusione di questa breve panoramica è interessante segnalare una pubblicazione del 2004 “segni e disegni, nero, bianco e colore... città a confronto sull’espressività infantile”[17] realizzata da più soggetti: scuole dell’infanzia, nidi, musei, che hanno posto la ricerca sul segno e sul colore come elemento di confronto. 4. un’indagine tra futuri maestri e bambini dopo aver preso in considerazione alcune esperienze diverse tra di loro, ma accomunate da un’evidente qualità educativa, che si caratterizza per la presenza di alcune costanti, quali: sperimentazione diretta di ogni bambino di più strumenti e materiali, azione condivisa con il gruppo, dei pari e degli adulti, riflessione a partire dalla pratica, sviluppo di ipotesi e verifica fattuale, rielaborazione successiva delle conoscenze, fruizione consapevole di opere d’arte, rivolgiamo ora il nostro sguardo al presente. indubbiamente molte sono le attività didattiche proposte ai bambini, innumerevoli i suggerimenti espressi dalle guide e dalle riviste scolastiche, come pure importanti i riverberi del colore nell’allestimento degli spazi, ambienti e arredi a scuola, ma quante di queste scelte sono effettuate in modo totalmente consapevole, che idee hanno gli insegnanti su questa tematica? in che modo il colore viene messo a tema nelle azioni didattiche? per iniziare a rispondere a questi interrogativi si è resa necessaria una prima indagine esplorativa, svolta su un campione di 124 studenti iscritti al terzo anno del corso di laurea in scienze della formazione primaria dell’università di milano bicocca, frequentanti il corso di educazione all’immagine. a loro sono stati somministrati due questionari, il primo a domande aperte, utilizzato come indagine pilota, grazie alle cui risposte è stato elaborato un secondo questionario semistrutturato [18]. la decisione di individuare gli studenti del terzo anno, come campione significativo, è stata fatta per tre motivi: innanzitutto ognuno di loro ha scelto e sta completando un percorso universitario che lo porterà ad essere, all’incirca tra un anno un futuro insegnante abilitato, nella scuola dell’infanzia o nella scuola primaria; in secondo luogo tutti hanno ormai sviluppato una buona conoscenza di almeno tre scuole, poiché da due anni stanno compiendo un percorso di tirocinio, della durata di 290 ore complessive e; in terzo luogo si sono già sperimentati in momenti di attività d’insegnamento in prima persona, dopo averli alternati a momenti di osservazione e di riflessione, coordinati grazie ai tutor ospitanti e ai supervisori. la conoscenza diffusa delle scuole di milano e della lombardia, l’osservazione specifica dall’interno della realtà scolastica, l’attenzione nei riguardi di una didattica attiva e laboratoriale, studiata nei corsi e sperimentata nei laboratori, e laddove possibile, utilizzata direttamente nella realizzazione di attività didattiche singole e oltre che di percorsi più articolati, insieme alla freschezza dei propri ricordi nei confronti della storia scolastica sono state caratteristiche importanti tenute in considerazione nell’elaborazione del questionario e nella scelta di questo campione. i fuochi attorno ai quali si è articolato il secondo questionario sono stati tre: il primo punto d’attenzione autobiografico legato alla loro infanzia e alle esperienze significative compiute sul colore, per cogliere se queste azioni si fossero sviluppate nella scuola o in altro ambiente e di che tipologia fossero state, il secondo fuoco era riferito al presente e alle attività attuali ritrovate nelle scuole legate a questa tematica, il terzo punto di indagine era sulle loro conoscenze in questo ambito, sulle preferenze attuali e del passato oltre che sulle proposte fatte o da voler realizzare in futuro nella scuola. i questionari compilati sono stati 124, il 97,58% degli intervistati erano donne, l’età media è risultata 22 anni. sul primo punto indagato, “hai un ricordo delle tua infanzia legato al colore?” la stragrande maggioranza, il 73%, ha risposto di sì e lo ha raccontato, per il 37% si trattava di oggetti, vestiti, giochi, paesaggi del passato, ricordi familiari o comunque non legati all’ambito scolastico, mentre per il 36% era invece una “cosa” incontrata a scuola o un’azione collegata ad un’attività didattica, svolta in aula, in sezione 1302/14 | cultura e scienza del colore color culture and science o nei laboratori. la proposta più menzionata è stata quella dell’impronta delle mani e dei piedi realizzata o al nido o nella scuola dell’infanzia, le altre attività si riferivano invece alla coloritura o alla pittura, pochissime quelle che hanno citato sperimentazioni più articolate. concentrandosi invece sul presente, alla domanda riferita alle attività osservate a scuola riferite al colore: “in base a quanto hai osservato nelle scuole in cui hai fatto tirocinio o dove lavori il colore viene tenuto in considerazione?” il 66%, la maggioranza ha risposto di sì, il 33% di no. la presa in carico di questo argomento, per quello che riguarda singole attività o percorsi è evidente, molto meno, invece, per quello che riguarda la cura di ambienti e degli spazi, dato dedotto dalla domanda successiva qui non sviluppata con un grafico specifico. alla richiesta se avessero visto direttamente realizzata una o più proposte sul colore, il 59% ha risposto di sì, il 41% di no. la proposta si colloca in prevalenza nella scuola dell’infanzia, con un 38%, solo con il 21% nella scuola primaria l’attività vista è riferita in maggioranza alla pittura e alla coloritura, ben distaccati si collocano la manipolazione, il gioco, il collage, l’elaborazione di cartelloni, e altro. l’ambito disciplinare a cui afferisce la proposta per la maggioranza risulta l’educazione artistica, tra le altre discipline la più coinvolta è l’italiano . entrando nello specifico, in merito alla conoscenza di che cosa fosse il colore, (la domanda era: “in base alle tue conoscenze attuali, secondo te che cosa è il colore?”) solo il 24% ha formulato definizioni scientifiche corrette, mentre il 12% ne ha dato una definizione scientifica imprecisa, il 10% una sbagliata, il 15% non ha risposto, la maggioranza, il 39%, ha espresso una definizione esclusivamente emotiva, senza alcun riferimento scientifico, cogliendo con questo un aspetto sottolineato da lia luzzato e renata pompas “quando si parla di colore, fatalmente si evocano, insieme alla sua immagine, sensazioni, emozioni, ricordi.” [19]. nel campo delle preferenze personali nei confronti del colore, riferite all’infanzia, il rosa è risultato il colore più scelto 25,8%, nel presente vincono il blu 17,7% e l’azzurro 16,1%, mentre il rosa retrocede a una posizione nelle retroguardie, solo al 4%. quando si entra nella descrizione delle attività che loro stessi hanno proposto alle classi e alle sezioni, il 37% affermano di aver tenuto presente il colore, il 63% no, ma l’interesse nelle attività sviluppate è parso per la grande varietà di ciò che hanno presentato (pittura, ombre, esplorazioni visive e tattili, fumetti, mosaici, giochi con l’acqua, matematica e colori, musica e colori, emozioni e colori, giochi, …). all’ultima domanda riferita alla possibilità di lavorare sul colore nel prossimo futuro di insegnante prospettando un’ipotesi di lavoro, solo il 10% non risponde, mentre gli altri, il 90%, risponde affermativamente sviluppando una proposta ancorata alla sperimentazione di strumenti e di materiali. dai dati raccolti emerge, dunque, come quasi tutti abbiano un ricordo dell’infanzia legato al colore, vissuto per la maggioranza in ambito scolastico. nel loro passato di scolari, l’attività 14 cultura e scienza del colore color culture and science | 02/14 con il colore è stata estremamente limitata, vincendo l’aspetto della coloritura con le matite, i pennarelli, sviluppato in modo veristico, rarissime le sperimentazioni, in questo caso ben impresse nella memoria. attualmente sono molte le azioni che gli studenti hanno visto realizzate nelle scuole, limitate le attenzioni nei confronti dell’arredo [20], ma la specificità dei lavori rimane legata più all’individuazione, all’elencazione dei colori, allo studio per caratteristiche, alla coloritura, è ancora molto meno presente l’esplorazione e la ricerca. poche sono le conoscenze scientifiche corrette degli studenti nei confronti del colore, molte quelle imprecise o errate, evidente soprattutto la grande importanza e la priorità data all’aspetto emotivo quando ci si misura con questa tematica. da parte loro alcuni studenti hanno già provato a lavorare con il colore, nella scuola dell’infanzia e nella scuola primaria, avendo in mente un ventaglio variegato di possibilità in cui i campi disciplinari si possono contaminare. in contemporanea al questionario proposto agli studenti, nell’anno 2001-2012, in cinque scuole dell’infanzia e primaria, sono state svolte delle interviste ai bambini per scoprire le loro preferenze [21] e la loro conoscenza dei colori, questo per iniziare a indagare quali informazioni avessero su questo argomento senza aver avviato nessun tipo di lavoro specifico. successivamente nell’aprile 2012, a seguito dei dati raccolti dalle interviste, è stato proposto un questionario semistrutturato ai bambini, di due classi quarte della scuola rinnovata di milano, per un totale di 43, le domande sono state relative all’individuazione dei colori, alle loro preferenze, alle implicazioni che queste preferenze comportano nella scelta di vestiti, oggetti,..., a una definizione di colore, allo strumento/i privilegiati per colorare ed infine ai ricordi legati ad esperienze effettuate con i colori. dalle risposte sia delle interviste, che del questionario è emersa una grande competenza. in particolare dal questionario si è potuto rilevare come tutti i bambini, italiani e stranieri, conoscessero, discriminassero, nominassero e sapessero scrivere all’incirca sedici colori. molto definiti e articolati i gusti specifici, motivati, che, ricadono anche nelle scelte di acquisto, tutti hanno chiesto almeno una volta di comperare oggetti e vestiti con un colore individuato. quasi tutti, l’81,4%, decidono spesso i colori con cui vestirsi la mattina, mentre il 18,6% non lo sceglie. il 97,7% ha scelto uno o più oggetti influenzato dal colore, solo il 2,3% risponde di no. nelle definizioni date della parola colore, (la domanda era “secondo te che cosa è il colore? prova a spiegarlo con una frase”) l’unico aspetto indagato è stato quello legato alla sensibilità e all’emotività, nessun riferimento è stato fatto all’ambito scientifico. il 95,3% degli intervistati ha affermato di ricordarsi di un’attività svolta legata al colore, e ne hanno dato una descrizione unita ad un’azione che si colloca per la maggioranza nell’ambito scolastico e riguarda la pittura. un’ultima domanda è stata quella riferita al colore da loro preferito, che ha permesso di cogliere una grande varietà di scelte. da questo primo approccio, che non ha nessuna caratteristica di esaustività, emerge come le conoscenze attuali dei bambini nei confronti del colore siano molto più articolate di come la legislazione e la stessa azione didattica si immaginano, evidenziando questo aspetto, la scuola potrebbe porsi l’obiettivo di non limitarsi più solo ad attività di coloritura veristica e di discriminazione, ma potrebbe rivolgersi verso una vera e propria sperimentazione in molti campi, approfondendo, implementando, arricchendo conoscenze e informazioni, già acquisite in modo non formale, vivendo in una civiltà come quella attuale, così esposta sul fronte dell’immagine. il colore è un argomento di tale complessità culturale e ricchezza, per gli aspetti impliciti nella sua storia [22], per le ripercussione filosofiche e intellettuali [23], per le scoperte scientifiche [24], per la varietà e profondità con cui viene utilizzato nel mondo dell’arte [25], del design [26], della moda, e della pubblicità [27]…che vederlo ridotto a semplici esercizi semplificati e ripetitivi rischia di banalizzarne il senso. attività prescrittive corrono il rischio di segmentare un ambito di sapere così complesso e intrigante, restituendo ai bambini, che stanno vivendo una stagione di forza vitale, di attenzione e di fascino proprio nei confronti del colore, una visione semplicistica e parcellizzata di un contenuto di così ampio spessore. 1502/14 | cultura e scienza del colore color culture and science 5. due studi di caso in cui il colore diviene promotore di conoscenza conclusa questa prima indagine, sembra necessario ora analizzare due studi di caso [28], premettendo che non si tratta di percorsi estremamente elaborati, ma di azioni articolate in cui il colore è stato proposto con modalità differenti utilizzandolo per sperimentare, riflettere, costruire conoscenze condivise. punto fondante dei due percorsi è il rapporto con l’arte, ipotesi elaborata in molte esperienze seppure con maniere differenti [29]. l’idea è che usare opere d’arte come tramite immediato e input di sperimentazioni, o attraverso una visione diretta in museo, o grazie a buone riproduzioni utilizzando l’ausilio delle varie tecnologie in sezione e in classe, possa permettere al colore di proporsi in modo più composito e approfondito, senza cadere in eccessive semplificazioni e in usi stereotipati. nel primo caso [30] il progetto è stato realizzato nella scuola dell’infanzia di cardano al campo, nell’anno scolastico 2009/2010, con venticinque bambini, grazie a un’azione di gioco e di scoperta, arrivando poi alla conoscenza diretta e sperimentale di alcune riproduzioni delle opere di wassilij kandinskij. fin dalla fase di osservazione, precedente alla proposta, si era colto come la maggioranza dei bambini, quasi tutti di quattro anni, a fronte di attività di semplice coloritura delle schede, copiatura dei disegni già fatti alla lavagna, mantenessero solo per pochi minuti la concentrazione, mentre nei disegni realizzati durante il gioco libero l’attenzione rimanesse molto viva. la scelta di proporre kandinskij si prestava per la ricca gamma di forme e di colori, i quadri veniva offerti alla visione, insieme a narrazioni, suggestioni musicali, in un secondo momento con modalità ogni volta diverse per tredici incontri, si andava a sperimentare liberamente: dai materiali tridimensionali, alla lavagna luminosa con carte veline e acetati, al collage di carte colorate, alle stoffe, alle tempere con scatole e palline, agli ecoline e alle macchie simmetriche, ad un ascolto musicale concretizzato poi in una danza e una pittura su fogli bagnati, alla coloritura con il sale e con le carte veline, all’uso di bottoni, fili, materiali del quotidiano. ogni azione aveva una grande attenzione nei confronti della verbalizzazione, ad esempio, giocando con le tempere per creare nuovi colori l. (quattro anni) arrivava ad affermare: “io (unisco) rosso e nero, diventa fuoco e sangue!” e tutti incessantemente commentavano quanto andavano facendo, un altro fattore interessante è stato l’uso del “sembra” e di un tempo maggiore per osservare le cose e per ipotizzare più soluzioni per come poter sviluppare i materiali accostati, e utilizzare i colori prima di mettersi all’opera. nel secondo caso [31] si tratta di un’esperienza di tirocinio, durata un intero anno scolastico (2010-2011), in una classe prima della scuola primaria g. pascoli i.c. di varese 2, in cui la proposta fatta alla classe, ha compreso numerose fasi: osservazione e raccolta dei disegni spontanei, interviste ai bambini, individuazione delle conoscenze pregresse sulla tematica colore, discussioni, sperimentazione libere e indirizzate con materiali e strumenti vari (con colori naturali, su diversi supporti, utilizzando tracce e impronte). all’interno di questo percorso un posto essenziale ha trovato la visita a villa menafoglio litta panza di biumo, bene del fai, e alla collezione permanente di dan flavin [32]. l’uscita al museo, ha permesso di confrontarsi con la tematica del colore a tutto tondo, esplorandolo nelle installazioni presenti nei rustici della villa e sperimentando poi in laboratorio al buio la creazione di luci, di colori e di forme, con lampadine e fogli. la fase di esplorazione è continuata a scuola con materiali sempre diversi, l’azione si è sviluppata avendo come punto di riferimento anche la palestra, al buio e poi alla luce. il termine del percorso, condiviso con i genitori è stata un merenda colorata, in cui accanto alla documentazione e ai lavori esposti, si è organizzata una festa sul tema del colore. i risultati dei lavori, in termini di arricchimento del vocabolario, di ricchezza e articolazione della produzione, condivisione sociale tra piccoli e adulti, sono dimostrati dalla raccolta della documentazione. il punto di snodo delle due progettazioni è stato l’incontro con l’opera d’arte, attentamente individuata e studiata in precedenza dall’adulto, intesa come esperienza emozionale, di stupore, di estetica e di formazione [33], “pre-testo” [34] nei confronti di un apprendimento globale, insieme a una ricchezza di proposte e di materiali molti dei quali inusuali per l’ambito scolastico, ma riscoperti dal quotidiano con un occhio differente. l’uso del colore non è dunque rimasto relegato all’ambito dell’esercizio e della nomenclatura, ma si è concretizzato in sperimentazioni e pensieri. 6. conclusioni tornando alla domanda che aveva motivato l’indagine, sul rapporto tra colore e scuola, possiamo sottolineare come questa relazione non sia stata sempre riconosciuta e valorizzata nella legislazione scolastica, alternando un’azione di conoscenza e individuazione di problematiche nella percezione, a azioni, peraltro poco delineate, legate alla fruizione e produzione. limitandosi in ogni caso solo a un settore della conoscenza, quello che prevede il riconoscimento dei colori, la capacità di nominarli, differenziarli, usarli soprattutto correttamente da un punto di vista realistico 16 cultura e scienza del colore color culture and science | 02/14 per quanto concerne la coloritura. da parte dei bambini e degli insegnanti, invece, si può sostenere come l’importanza sia riconosciuta, anche se il colore viene esplorato più sotto l’aspetto emozionale, invece che da un punto di vista di conoscenza scientifica/sperimentale. la messa a tema all’interno della scuola risulta molto legata agli interessi personali di educatori e insegnanti, anche se spesso viene riconosciuta la valenza formativa di questo aspetto, sia nella definizione e nell’allestimento degli ambienti, sia nelle proposte didattiche. difficile è osservare, come pratica diffusa, un’azione articolata, esperienziale, di ricerca con tutti i riverberi possibili nelle varie discipline. quando il colore viene proposto l’ambito rimane quello dell’educazione all’immagine, rischiando di limitarsi ad aspetti parcellizzati, ad attività di coloritura, di individuazione, di definizione. laddove invece il colore sia messo a tema in modo più globale, con un’aderenza anche alle opere artistiche [35], moderne e contemporanee, notevoli sono le ripercussioni positive nei bambini, in termini di espressioni linguistiche comunicative, produzioni grafiche, pittoriche e tridimensionali, oltre che di capacità sociali e relazionali, utilizzando, infatti necessariamente, la modalità laboratoriale come elemento imprescindibile delle proposte. interessante evidenziare come l’attenzione alla complessità di questo oggetto culturale, necessiti di un medium alto, come l’utilizzo di opere d’arte, l’uso di ipotesi scientifiche, l’articolazione in più discipline, per non rischiare di perderne in una modalità di presentazione semplicistica il valore culturale aderente alla nostra contemporaneità. bibliografia [1] franklin, e. gibbons, k. chittenden, c. taylor & j. alvarez, “infant color preference for red is not selectively context specific”, in emotion, in press, 2011; i. k. zemach, d. y. teller, “infant color vision: infants’ spontaneous color preferences are well behaved” in vision research, 47, pp. 1362-1367, 2007; a. franklin, m. pilling & i. r. l. davies, “the nature of infant colour categorisation: evidence from eye-movements on a target detection task”, journal of experimental child psychology, 91, pp.227-248, 2005. [2] t. r. garth, e. p. porter, “ the color preferences of 1032 young children”, in the american journal of psychology, vol. 46, n.3, pp.448-451, jul 1934; r. g. suchman, “cultural differences in children’s color and form preferences” in the journal of social psychology, 70, pp.3-10, 1966; i. l. child, j. a. hansen, f. w. hornbeck, “age and sex differences in children’s color preferences” in child development, vol.39, n.1, pp.237-247, mar. 1968; r. melkman, a. koriat, k. pardo, “preference for color and form in preschoolers as related to color and form differentiation” in child development, vol. 47, no. 4 (dec., 1976), pp. 1045-1050; m. a. read, d. upington, “young children’s color preferences in the interior environment”, in early childhood educ, 36, pp.491-496, jul 2009 [3] c. ricci c. (1887), “l’arte dei bambini”, armando editore, roma, 2007 [4] c. ricci c. (1887), “l’arte dei bambini”, armando editore, roma, 2007, paragrafo “il bimbo e il colore”, p.74. [5] c. ricci c. (1887), “l’arte dei bambini”, armando editore, roma, 2007, p.74-75 [6] la denominazione scuola dell’infanzia e scuola primaria è quella attualmente utilizzata, a seconda degli anni di promulgazione delle leggi si utilizzerà la corretta definizione: asilo, scuola materna, scuola elementare. [7] c. schulof, “étude de la couleur chez des enfants de 5 à 13 ans”, psychologie française, paris, tome 24, n.°2, p.111-128, 1979. [8] v. lowenfeld, w. l. brittain (1960), “creatività e sviluppo mentale”, giunti, firenze, 1967. [9] e. cannoni, “il disegno dei bambini”, roma, carocci editore, 2003; g. bartoli (1989), “il disegno nelle fasi evolutive”, “scritti di psicologia dell’arte e dell’esperienza estetica”, monolite editrice, roma, pp.219-243, 2003; r. quaglia, g. saglione, “il disegno infantile: nuove linee interpretative”, giunti barbèra, firenze, 1976. [10] c. golomb.(2002), “l’arte dei bambini. contesti culturali e teorie psicologiche”, raffaello cortina editore, milano, 2004. [11] c. golomb ., “the child’s creation of a pictorial world”, university of california press, berkeley, 1992. [12] f. de bartolomeis, “il colore dei pensieri e dei sentimenti. nuove esperienze di educazione artistica”, scandicci firenze, la nuova italia, 1990. alcune proposte legate a questo argomento si trovano anche in f. de bartolomeis, “nuove esperienze di educazione artistica”, azzano san paolo (bg), edizioni junior, 1997. [13] f. de bartolomeis, “l’arte per tutti. conoscere e produrre”, azzano san paolo (bg), edizioni junior, 2003. [14] b. munari (a cura di), “il laboratorio per bambini a brera”, bologna, zanichelli, 1981, in particolare sul colore, pp.38-41. su questa stessa tematica vedi r. eco, (a cura di) “ il rosso”, bologna, zanichelli, 1979; r. eco, “a scuola col museo, guida alla didattica artistica” milano, bompiani, 1986, l’autrice ha proseguito il lavoro di munari nello stesso museo. sul metodo giocare con l’arte si veda metodo bruno munari© e il sito ad esso collegato www. brunomunari.it/index2.htm [15] c. edwards, l. gandini, g. forman (a cura di), (1995) “i cento linguaggi dei bambini. l’approccio di reggio emilia all’educazione dell’infanzia”, azzano san paolo (bg), edizioni junior, 2000, p.156. [16] l’atelier raggio di luce, aperto nel 2006 all’interno del centro internazionale loris malaguzzi, nasce da uno scambio e una collaborazione tra l’esperienza pedagogica dei nidi e delle scuole dell’infanzia del comune di reggio emilia, reggio children e il dipartimento di scienze e metodi dell’ingegneria della facoltà di ingegneria dell’università degli studi di modena e reggio emilia. [17] p. pontiggia, s. reali, a. acerbi, (a cura di) “segni e disegni. nero, bianco e colore... città a confronto sull’espressività infantile”, edizioni junior, azzano s. paolo, 2004. [18] il questionario semistrutturato è stato somministrato il 27/3/2012. per l’elaborazione dei questionari ci si è riferiti a:s. mantovani (a cura di), “la ricerca sul campo in educazione. i metodi qualitativi”, mondadori, milano, 1998; a. bosco, “come si costruisce un questionario”, carocci, roma, 2003; c. bove, “ricerca educativa e 1702/14 | cultura e scienza del colore color culture and science formazione. contaminazioni metodologiche”, franco angeli, milano, 2009; [19] l. luzzato, r. pompas, “il significato dei colori nelle civiltà antiche”, rusconi, milano, 1988, p.7. [20] la tematica della cura degli arredi e degli allestimenti degli spazi scolastici è purtroppo ancora troppo poco preso in considerazione:c. burke, “inspiring spaces: creating creative classrooms” in creative spaces for learning, cb,, vol5, n.°2, 2007; g. bertagna, a. bottoli, perception design, maggioli editore, santarcangelo di romagna (rn), 2009; l. luzzato e r pompas., “il colore persuasivo”, il castello, milano 2001. [21] v. lobue, j. s. deloache, “pretty in pink: the early development of gender-stereotyped colour preferences” in british journal of developmental psychology, 29, pp.656-667, 2011 [22] m. brusantin, “storia dei colori”, einaudi, torino, 1983; p. ball, “colore una biografia”, rizzoli, milano, 2001; m. pastoreau, d. simonnet, “il piccolo libro dei colori”, ponte alle grazie, milano, 2006; m. pastoreau, “blu. storia di un colore”, salani, milano, 2008; m. pastoreau, “i colori del nostro tempo”, ponte alle grazie, milano, 2010. [23] j. w. goethe, “la teoria dei colori”, il saggiatore, milano, 2008; [24] p. bressan, “il colore della luna. come vediamo e perché”, laterza, roma-bari, 2009. [25] w. kandinsky , “dello spirituale nell’arte”, edizione se, milano, 1989; j. itten, “arte del colore”, il saggiatore, milano, 2010 [26] p. scarzella, “i colori del design: il progetto del colore come fattore di successo nei prodotti industriali”, f. angeli, milano, 2008. [27] l. luzzato, r. pompas, “colore&colori”, il castello, milano, 2009. [28] per lo studio di caso ci se è riferiti a l. mortari, “ cultura della ricerca pedagogica. prospettive epistemologiche”, carocci, roma, 2009. [29] c. francucci, p. vassalli, “ educare all’arte.”, electa, milano, 2005; c. francucci, p. vassalli, “ educare all’arte. immagini esperienze percorsi”, electa, milano, 2009. [30] il percorso è stato condotto, per un progetto di tesi, dall’allora studentessa alice palazzi, attuale insegnante. [31] il percorso è stato condotto, per un progetto di tesi, dall’allora studentessa marta giuliani, attuale insegnante. [32] m. magnifico, l. borromeo dina, “villa menafoglio litta panza e la collezione panza di biumo”, skira, milano, 2001; a. vettese (a cura di), “dan flavin. stanze di luce tra varese e new york”, skira, milano, 2004. [33] m. dallari, “la dimensione estetica della paideia. fenomenologia, arte, narratività”, erickson, trento, 2005. [34] m. dallari, “l’arte per i bambini” in c. francucci, p. vassalli, “ educare all’arte.”, electa, milano, 2005, pp. 1725. [35] a. boatto, “di tutti i colori da matisse a boetti, le scelte cromatiche dell’arte moderna”, laterza, roma-bari, 2008. cultura e scienza del colore color culture and science 4 cultura e scienza del colore color culture and science | 02/14 1andrea siniscalco andrea.siniscalco@polimi.it 1alberto seassaro alberto.seassaro@polimi.it 2paolo tinelli tinelli_paolo@libero.it 1claudio conio claudio.conio@polimi.it 1dipartimento di design politecnico di milano 2studio di architettura “tinelli paolo”, tinelli_paolo@libero.it le forme della luce: didattica del progetto con sorgenti colorate al neon 1. introduzione il corso di cultura e progetto della luce della facoltà del design del politecnico di milano, è un appuntamento annuale che vede gli studenti alle prese con la progettazione di un oggetto tecnico di sperimentazione estetologica. scopo del corso è sviluppare una conoscenza dei complessi rapporti di interazione fra luce e materia, presenti in natura e nella cultura, che determinano le condizioni di illuminazione che, consentono all’uomo la percezione del mondo visibile e la sua praticabilità materiale, al fine di pervenire alla consapevolezza e comprensione critica del ruolo fondativo che la luce ha storicamente svolto (e sempre più potrà svolgere nel contesto iper-tecnologico contemporaneo) nella determinazione progettuale degli artefatti ambientali e industriali. il corso affonda le sue radici in quello che era inizialmente un tentativo di ridare alla luce la completezza privatagli da una progettazione esclusivamente “tecnica” (o illuminotecnica) o attenta ai soli aspetti estetici. nell’interazione con la materia la luce assume diverse valenze. la prima è quella della “luce per vedere”, ovvero dell’utilizzo ai fini di illuminare un uno spazio (o un volume). questo modo di intendere la luce è il più diffuso, il più compreso, quello di cui si occupano maggiormente le normative, oggetto di studio e maggior motore di evoluzione tecnica. la luce serve per illuminare, vedere, rendere possibile la comprensione del messaggio veicolato dallo spazio considerato. poiché l’architettura (o lo spazio, o il significante che stiamo illuminando) possa adempiere alla sua funzione possa cioè essere”usata” occorre che la luce ne assicuri la praticabilità [1]. lo sviluppo dei prodotti, oltre che dal punto di vista del contenimento dell’abbagliamento, del rendimento delle sorgenti, della progettazione di componenti ottiche sempre migliori, si è negli anni spostato sul versante della cromaticità della luce, della possibilità di modificarla secondo necessità, andando a riproporre la dinamicità, che aveva perso con l’avvento dell’elettricità [2]. tuttavia, questo aspetto del “fare luce” è legato esclusivamente al rendere visibile l’ambiente, sia nei suoi aspetti comunicativi che in quelli di fruizione. un’altra valenza che la luce può assumere è quella di segnale, ovvero “luce come messaggio”. indipendentemente dalle necessità di “illuminare” un ambiente, gli spazi si sono sempre più riempiti di “segnali”, di messaggi veicolati spesso grazie allo strumento luce. spie di accensione e spegnimento, indicazioni di sicurezza, di posizioni, messaggi pubblicitari o comunicazione. per sottolineare quanto sia diversa la natura di questi due modi di usare la luce, basti pensare al fatto che mentre l’illuminazione di un ambiente richiede una particolare attenzione allo smorzamento dei gradienti di luminanza, nell’uso della luce come messaggio, i contrasti, risultano invece molto importanti. zone d’ombra che possono ospitare messaggi quindi, vanno sempre più a contendere gli spazi alla luce utilizzata “per vedere”. anche questa forma di comunicazione ha una sua spinta sullo sviluppo tecnologico, anche se molto più recente di quella inerente alla “luce ambiente”. soprattutto l’avvento dei led prima e gli oled successivamente, ha portato evoluzioni in questo settore. si passa quindi da un contesto di “luce che illumina la forma” alla “forma della luce”. vi è infine un’altra valenza che si può attribuire alla luce: l’arte. la “light art” è da sempre molto diffusa, anche se è un ambito che non incide direttamente sullo sviluppo delle tecnologie, quanto piuttosto, può venirne influenzato con lo scopo di aiutare l’artista a poter esprimere i propri messaggi. un esempio di applicazione di tecnologie innovative nell’ambito della light-art è osservabile nei lavori di kit webster [3]. l’arte, è un filone parallelo, che può anche ignorare evoluzioni derivanti dagli altri settori; ne è un esempio la neon-art, dove la tecnologia impiegata è praticamente invariata (se non per migliorie nell’ambito dei materiali utilizzati) da un centinaio d’anni. questo settore ha visto opere di artisti come lucio fontana, mario merz, joseph kosuth, o il contemporaneo bruce nauman. la “luce messaggio” e la “light-art”, rappresentano un linguaggio ben specifico, ricco di componenti che non possono essere trascurate, quali ad esempio la forma e il colore, elementi tipici anche di quella forma di comunicazione che è la pubblicità, l’insegnistica. da qui, la volontà di dedicarsi a luce, forma e anche colore. 2. i progetti “la forma della luce”, è un tema volutamente molto ampio che ha concesso agli studenti dell’a.a. 2009/2010, di spaziare su più argomenti 502/14 | cultura e scienza del colore color culture and science trasversali, che hanno in parte incrociato la didattica svolta in apertura del corso e in parte hanno consentito approfondimenti personali su temi di ampio respiro come l’arte, l’architettura, ma anche la comunicazione, l’ambito sociale, e via discorrendo. l’utilizzo del colore nella progettazione degli oggetti è stato conseguenza del mezzo con cui si è scelto di operare; i tubi al neon utilizzati tipicamente per le insegne sono fortemente radicati nell’immaginario di ognuno come segni luminosi che si fanno spesso messaggeri di quella cultura pop dalla quale anche il design ha tratto ispirazione. i vincoli di progetto (necessari per poter produrre fisicamente gli oggetti) prevedevano che gli studenti sviluppassero, all’interno di uno “spazio cubico” di 30 centimetri di lato, un allestimento luminoso con tubi al neon del diametro di 1 centimetro. inevitabile per tutti gli studenti è stato confrontarsi con il tema del colore. solo due oggetti, su 21 realizzati non utilizzano apertamente il colore, ma non per escluderlo dalla loro visione del progetto, quanto piuttosto perché hanno ritenuto che dal punto di vista cromatico, il bianco, fosse il più calzante ai concetti che avevano intenzione di esprimere. il numero dei colori resi disponibili (sono numerosissimi i colori riproducibili con i tubi al neon) è stato ridotto notevolmente, nei vincoli di progetto. le caratteristiche cromatiche dei tubi al neon possono derivare da più fattori; la tipologia di gas utilizzato, la colorazione della pasta del vetro o la copertura interna con polveri al fosforo. la luce colorata risultante, a seconda che si utilizzi un metodo anziché un altro, varia sensibilmente (differente intensità, colori più o meno saturi) e spesso, accoppiare colori ottenuti in un modo con altri ottenuti diversamente può portare a risultati non propriamente soddisfacenti. questa è una delle problematiche inerenti al colore che gli studenti del corso hanno dovuto affrontare, dal momento che il numero di colori messi a loro disposizione era limitato e variabile nelle tipologie descritte. si è quindi osservata la necessità di creare accostamenti cromatici in funzione ai differenti risultati ottenibili, andando a interpretare anche le differenti qualità della luce colorata, cercando di armonizzare il risultato non solo dal punto di vista della tinta, ma anche in relazione alla luminosità ottenibile e alla saturazione del colore. di seguito sono riportati alcuni esempi di progetto. “spectrum”, lavoro che rievoca l’andamento spettrale della luce, associando differenti lunghezze d’onda (riprodotti con curvature più o meno ampie nei tubi), ai corrispettivi colori. utilizzando quindi il colore blu per tubi con un maggior numero di curvature fino ad arrivare al rosso per tubi che descrivono curve più ampie. “red & blue” provoca un conflitto cerebrale tra l’emisfero destro e l’emisfero sinistro del cervello, utilizzando il colore per determinare nel fruitore uno straniamento, creato dall’inaspettato confondersi di iconicità e simbologia dei colori rosso e blu. i tubi di vetro delle lampade sono riempiti di due differenti gas (neon e argon) che gli conferiscono una colorazione rossa e blu solo se accesi, mentre rimangono trasparenti da spenti. “spettro”, ci mostra una riproduzione (semplificata) del fenomeno della dispersione della luce scoperto da newton. un prisma stilizzato con un tubo all’argon (azzurro) scompone un raggio di luce bianca in differenti raggi di luce colorata (meno della normale dispersione per problemi legati alla realizzabilità del pezzo). “composizione rbyw” ci riporta alle tematiche correlate a mondrian e al suo uso del colore. l’oggetto trae origine dall’opera “composizione” del 1921. non essendo possibile riprodurre le campiture dell’opera, gli studenti hanno invertito il concetto dell’utilizzo del colore, utilizzando linee colorate sul fondo nero dell’oggetto. gli intrecci risultanti rievocano gli incroci dell’opera originale riproponendo i colori primari del sistema ryb. “brain light” simula un cervello tramite un intreccio di tubi al neon, dividendolo in tre settori distinti fra loro per forma e per colore. il colore rosso viene utilizzato per l’intreccio caotico dell’emisfero destro, che presiede al pensiero creativo e all’emotività, il colore blu, è per l’emisfero sinistro (disposto in maniera ordinata) nel quale risiede il pensiero organizzativo e la razionalità. i due emisferi sono poi messi in comunicazione da un “corpo calloso” simulato da un neon bianco. “enola gay” è un omaggio all’iconografia pop. il profilo del’ b52 superfortress diventato tristemente famoso per il bombardamento atomico di hiroshima e nagasaki, è riprodotto con linee morbide che richiamano il tratto di keith haring. i colori evolvono dal rosso dell’esplosione salendo verso un giallo che evapora nel bianco che rappresenta la fusoliera luminosa. “rainbow city” rappresenta un oggetto con una duplice natura (in funzione del punto di osservazione), quella artificiale data dallo skyline di una città stilizzata, mentre per l’elemento naturale si è fatto ricorso all’utilizzo del colore, rappresentando una “versione ridotta” 6 cultura e scienza del colore color culture and science | 02/14 figura 1 i colori resi disponibili agli studenti per il progetto, raccolti in un box dimostrativo figura 2 -“spectrum” di e. borella e f. castegnaro. figura 4 e 5 a sinistra,“red & blue” di m. accetti, d. barosi, e. beghi, m. bonardi e d. ulukan. l’alternarsi dei tubi accesi crea una confusione sensoriale tra i due emisferi del cervello di chi osserva. a destra, “spettro” di e. catania, m. gianola, s. sagripanti, s. tommasi 702/14 | cultura e scienza del colore color culture and science figura 6 e 7 a sinistra, “composizione rbyw” di v. fila vaudana, a. giacobi, l.gulinatti, s. klocker, e. leonardo. a destra, “brain light” di v. neirotti, m. pala, m. pelucchi, a. pepe, c. pizzocchero. figura 8 e 9 a sinistra, “enola gay” di l. manzinello, s. sartori, m. toni, l. veronese. a destra, “rainbow city” di e. bertolini, m. menini, r. nicoli, c. pastormerlo, n. piccaluga figura 10 – alcune fasi della realizzazione dei progetti. 8 cultura e scienza del colore color culture and science | 02/14 (i vincoli stabilivano un numero limitato di colori e tubi utilizzabili) di un arcobaleno. una città che quindi appare dinamica e risultante da una confusione di colori e l’ordinata cromaticità di un arcobaleno. 3. collaborazioni la scelta di realizzare i progetti con qualità industriale, anziché lasciare agli studenti il compito di cimentarsi con la creazione di prototipi funzionanti, è stata presa a monte del corso, ancora prima di decidere per il tema. l’utilizzo dei tubi al neon implica il coinvolgimento di una struttura attrezzata per lavorare queste particolari sorgenti di illuminazione; questo è perfettamente in linea con la volontà di favorire il dialogo tra università e azienda. gli oggetti finali sono stati realizzati dall’azienda eliosneon, di vimodrone (milano), che ha ricevuto schizzi, rendering, modelli di lavoro e tavole tecniche direttamente dagli studenti ed è intervenuta in alcuni momenti di revisione per fornire supporto tecnico sulla realizzabilità dei prodotti. 4. conclusioni come già detto, la luce può essere trattata sotto svariati punti di vista, tuttavia, troppo spesso viene considerata solo dal punto di vista criticoestetico o tecnico-quantitativo, senza prendere in considerazione il vasto potenziale culturale e comunicativo della materia. nell’ambito del corso, lo sviluppo di oggetti di sperimentazione estetologica, che non vogliono essere oprere d’arte, ma punti di partenza per l’espressione di messaggi veicolati dalla luce, vuole essere un passo verso la formazione di “operatori della luce” che possano agire in maniera “programmata” e “consapevole” (per citare hans sedlmayr [4], che elaborò il problema dell’estetica della luce nell’arte), facendo emergere le piene potenzialità di questa materia ricca di significati, ma articolata e complessa al tempo stesso. bibliografia [1] a. seassaro, dalla “luce ambiente” alla “luce messaggio” appunti per una rifondazione teorica del rapporto tra luce e architettura. flare, n.1 pp 113 123. [2] a. siniscalco, f. musante, m. rossi, apparecchi di illuminazione con luce colorata e loro misura atti della quinta conferenza nazionale del gruppo del colore. palermo 2009, pp 255 266 [3] http://kitwebster.com.au [4] h. sedlmayr, la luce nelle sue manifestazioni artistiche ed. aesthetica, centro internazionale studi di estetica, 1994 cultura e scienza del colore color culture and science 01 14 riv is ta s em es tr al e | h al fye ar ly jo ur na l rivista dell’associazione italiana colore cultura e scienza del colore color culture and science cultura e scienza del colore color culture and science rivista dell’associazione italiana colore issn 2384-9568 direttore responsabile | editor-in-chief maurizio rossi vicedirettore | deputy editor davide gadia comitato scientifico | scientific committee giulio bertagna aldo bottoli osvaldo da pos bepi de mario renato figini davide gadia lia luzzatto veronica marchiafava claudio oleari renata pompas alessandro rizzi maurizio rossi andrea siniscalco francesca valan collaboratori | contributors giovanni bartolozzi, anna j. berolo, giulio bertagna, cristian bonanomi, aldo bottoli, chiara brunettin, daria casciani, costanza cucci, lia luzzatto, renata pompas, osvaldo da pos, bepi de mario, marco de vita, davide gadia, veronica marchiafava, daniele marini, marcello picollo, alessandro rizzi, maurizio rossi, desirée sabatini, francesca valan redazione | editorial staff aldo bottoli, daria casciani, davide gadia, francesca valan editore | publisher gruppo del colore – associazione italiana colore cultura e scienza del colore color culture and science rivista dell’associazione italiana colore registrazione presso il tribunale di milano al n. 233 del 24.06.2014 01numero 01 giugno 2014 number 01 june 2014 gruppo del colore associazione italiana colore prefazione | preface il restauro del colore digitale: un approccio basato sull’apparenza di anna j. berolo, desirée sabatini, cristian bonanomi, davide gadia, daniele marini, alessandro rizzi colori, segni, convenzioni e daltonici di giulio bertagna e aldo bottoli riproduzione di colori parzialmente nascosti da veli trasparenti di osvaldo da pos e chiara brunettin colore e turismo. sociologia dell’ospitalità turistica di bepi de mario misure di colore per la caratterizzazione e il monitoraggio di opere d’arte contemporanea di veronica marchiafava, giovanni bartolozzi, costanza cucci, marco de vita, marcello picollo colori cyber di renata pompas e lia luzzatto la percezione del colore nascita ai 3 anni di francesca valan coloured lighting, urban underground and human beings: relationship inquiry through showcase analysis by daria casciani and maurizio rossi james hillman, psicologia alchemica, adelphi edizioni, milano, 2013 a cura di renata pompas sommario | summary italiano english recensioni 01 4 8 13 16 21 26 31 35 40 45 4 cultura e scienza del colore color culture and science | 01/14 maurizio rossi molte realtà inerenti la scienza, cultura e professione del colore, operanti in italia da tanti anni sono confluite nel tempo nella nostra associazione, che ha nella conferenza nazionale del colore il suo principale momento di aggregazione annuale. nei paragrafi seguenti, a cura di osvaldo da pos, claudio oleari e alessandro rizzi, è riportata una storia di queste esperienze. all’assemblea dei soci della conferenza di palermo nel 2009 fu deciso di ampliare ulteriormente lo spettro di multidisciplinarietà partecipanti. dalla conferenza di lecce nel 2010 vi fu un costante aumento dei paper presentati. dal 2009 l’associazione si è effettivamente ampliata accogliendo esperienze nell’ambito della misura e strumentazione, del trattamento digitale, dell’illuminazione, della fisiologia e della psicologia, della merceologia, del restauro, della rappresentazione, dell’ambiente costruito, del design, della storia, della cultura e della formazione. accanto alla consueta pubblicazione degli atti della conferenza, nel 2013 l’associazione italiana colore ha deciso di pubblicare una rivista “cultura e scienza del colore – color culture and science” che consentisse di estendere e valorizzare gli articoli presentati alla conferenza e anche altri contributi esterni alla conferenza. nel 2014, prima della decima edizione della sua conferenza del colore, l’associazione ha quindi pubblicato un ulteriore strumento di divulgazione culturale, nella forma di una rivista semestrale, distribuita online in forma gratuita e accessibile a tutti. many realities in science, culture and profession of color, that since many years operate in italy, merged over the time in our association, that lives in the conferenza del colore his main moment of annual aggregation. in the following paragraphs, edited by osvaldo da pos, claudio oleari and alessandro rizzi a story of these experiences is reported. in the assembly of palermo 2009, members decided to widen the range of multidisciplinary approaches. since lecce’s conference in 2010 the presented papers where increasing any year. since 2009 our association effectively increased his size harboring experiences in the field of instruments and measuring, digital treatment, lighting, physiology and psychology, study of commodities, restoration, representation, in the field of constructed areas, of design, history, culture and education. beside the usual publication of the conference proceedings, in 2013 the associazione italiana colore has decided to publish a magazine “cultura e scienza del colore color culture and science” with the aim of extending and enhancing the papers presented at the conference and also accept other contributions external to the conference. in 2014, before the tenth edition of the conferenza del colore, the association has started publishing a half-yearly journal, freely available on-line for everyone. prefazione preface 501/14 | cultura e scienza del colore color culture and science alessandro rizzi il gruppo del colore nasce una sera dell’aprile del 2004, ad aachen in germania dove si stava svolgendo la conferenza colour in graphics, imaging and vision, cgiv 2004, conferenza che è a tutt’oggi il punto di riferimento europeo del colore nel campo delle immagini digitali. partecipando con claudio oleari a questa conferenza, abbiamo notato che era patrocinata da praticamente tutti i gruppi del colore europei, tranne quello italiano. decidemmo che valeva la pena tentare di allargare il gruppo di lavoro in colorimetria e reflectoscopia della siof, da lui coordinato, per cercare di farlo diventare un punto di aggregazione di tutti i professionisti e ricercatori che in italia lavorano con il colore, in ogni forma ed in ogni settore, come avviene negli altri gruppi del colore di tutto il mondo. la storia di come è andata nel dettaglio la racconta claudio nelle righe successive. io colgo l’occasione per ringraziare tutte le persone che hanno partecipato e che partecipano al gruppo ed in particolare claudio per la sua generosità e lungimiranza. claudio oleari prima di essere “gruppo del colore” della società italiana di ottica e fotonica (siof), la nostra organizzazione era “gruppo di lavoro in colorimetria e reflectoscopia” della siof e ciò è stato dal 1995 al 2004. per raccontare le origini riprendiamo la prefazione alla prima edizione degli atti, uscita nel 1998, e che raccoglieva le comunicazioni relativi a tre convegni, del 1995, 1996 e 1998. nel 1995 venne attivato il gruppo di lavoro in colorimetria e reflectoscopia in april 2004, the gruppo del colore was established at aachen, germany where the european conference on digital imaging, color in graphics, imaging and vision, (cgiv 2004) was held. whilst attending with claudio oleari, we noticed that every national color group, except the italian, were supporting the conference. i asked claudio the reason for such an absence. so, in the same way as other european national color groups, we decided to create a primary organization for all the italian professionals and researchers working in the field of colour. this has been done enlarging the pre-existing group of colorimetry and reflectoscopy (siof). the details of the story, are told by claudio in the lines below. before being “color group” of the italian society of optics and photonics (siof), our organization was “working group in colorimetry and reflectoscopy” of siof and this was from 1995 to 2004. the first edition of proceedings, started in 1998 and were composed by the communications on three conferences, 1995, 1996 and 1998. in 1995 the working group in reflectoscopy and colorimetry of the italian society of optics and photonics (siof) started. the reference model was the british color group, that was born over half a century earlier. the 6 cultura e scienza del colore color culture and science | 01/14 della società italiana di ottica e fotonica (siof). il riferimento e il modello fu il colour group inglese, ma questo nasceva oltre mezzo secolo prima. in una traduzione strettamente letterale e completa qui elenchiamo i suoi obiettivi, perché possono essere i nostri (mutatis mutandis): a) promuovere lo studio del colore in tutti i suoi aspetti, compresi gli aspetti relativi alla visione. b) offrire alle varie persone e/o ai vari gruppi di persone che hanno a che fare col colore nei suoi diversi aspetti, scientifico, industriale, estetico o didattico, l’opportunità di incontrarsi e di comunicare l’un l’altro i loro problemi. c) avviare l’attività necessaria o desiderabile per far crescere un’opinione rappresentativa sui vari problemi di standardizzazione, di specificazione, di nomenclatura e di tutti gli altri aspetti che il gruppo considererà necessari ad assistere la ricerca. d) incoraggiare e promuovere l’investigazione dei fenomeni del colore e la misurazione del colore e il tentativo di assicurare che si conoscano gli sviluppi che avvengono negli altri paesi del mondo. e) assistere la diffusione della conoscenza del colore. osvaldo da pos 1986, biennale di venezia. un gruppo di scienziati italiani, tra cui si possono ricordare marcolli, silvestrini, da pos, de grandis e molti altri, in occasione della 43° edizione della esposizione internazionale d’arte di venezia, unirono le loro forze e prepararono un’esibizione sulla percezione del colore e sulle illusioni del colore, che ottenne un grande successo (da pos o. colore e percezione. catalogo generale xliii esposizione internazionale d’arte. ed. la biennale di venezia, 1986, p. 137). objectives of the color group (great britain) are here reported, because they can also be our goals: a) to promote the study of color in all its aspects and also the related aspects of vision. b) to provide an opportunity for the various people and/or groups of people concerned with the scientific, industrial aesthetic and educational aspects of color to meet and become familiar with the problems of each other. c) to take all such steps as shall be necessary or desirable in endeavors to enable a representative opinion to be formed on various questions of standardization, specification, nomenclature and all other matters as the group shall consider necessary in order to assist research. d) to encourage and promote investigations of color phenomena and the measurement of color and endeavor to ensure that the members be aware of developments in other countries of the world. e) to assist in the dissemination of color knowledge. 1986 biennale di venezia. a group of italian scientists, among others worth of mention were marcolli, silvestrini, da pos, de grandis, and still many others, took the occasion of the 43rd international art exhibition of the biennale di venezia to join their forces and prepare an exhibition on colour perception and colour illusions for the biennale, which obtained a great success (da pos o. colore e percezione. catalogo generale xliii esposizione internazionale d’arte. ed. la biennale di venezia, 1986, p. 137). after that experience the group strengthened their links until 701/14 | cultura e scienza del colore color culture and science a seguito di quest’esperienza, gli appartenenti al gruppo rafforzarono i loro legami (sino ad allora prevalentemente informali) e iniziarono a produrre alcuni lavori come la partecipazione al meeting internazionale dell’aic “colour and environmental design” organizzato da werner spillmann in winterthur, 1988. nel frattempo (1987) un gruppo di professori e ricercatori dell’università di padova, fondò il centro interdipartimentale di “colore e arte”, nel quale i membri del dipartimento di psicologia generale, psicologia sociale e evolutiva, arti visive e musica, psicologia umana dell’università di padova, si unirono anche con altri studenti di università esterne pubbliche e private. in tutto i membri sono stati all’incirca 115 per l’intera durata del centro, mentre altre centinaia da altre parti dell’italia ne supportarono le iniziative. la storia delle attività del centro sono descritte al sito: http://www.psy.unipd.it/~dapos/. quando l’università di padova promosse e riformò i suoi dipartimenti e il gruppo, il centro di “colore e arte” non poté sostenere le ingenti spese necessarie per l’acquisto degli strumenti necessari e chiuse nel 2002. molti membri del centro presero parte alla conferenza di pescara (2004) e contribuirono alla nascita del gruppo del colore. then almost informal and started to perform some common work, like participating at the aic international meeting “colour and environmental design” organised by werner spillmann in winterthur, 1988. in the meantime (1987) a group of professors and researchers of the university of padua founded the interdepartmental centre “colour and art”, in which members of the departments of general psychology, developmental and social psychology, visual arts and music, human physiology of the university of padua merged with external scholars belonging to many other italian universities and public or private institutions. regular members (of the university of padua) and external members were about 115 persons for the whole period of life of the centre, while many hundreds from all parts of italy supported its initiatives. the history and the activities of the centre are described at http://www.psy.unipd.it/~dapos/. when the university of padua promoted a reform of its departments and centers, the colour and art centre could not afford the heavy institutional requirements needed for its survival and had to close in 2002. many members of the centre took part in the conference of pescara (2004) and contributed to the establishment of the italian colour group. cultura e scienza del colore color culture and science 1301/14 | cultura e scienza del colore color culture and science giulio bertagna aldo bottoli b&b colordesign giulio bertagna, aldo bottoli & partners colori, segni, convenzioni e daltonici 1. introduzione abbiamo dedicato una parte della nostra ricerca sui criteri progettuali di percezione e colore ai daltonici, perché sono utenti come noi che, a volte a ragione, ma spesso a torto, sono ritenuti non in grado di partecipare a determinate attività lavorative o, peggio ancora, persone di intralcio se non addirittura pericolose a causa della loro caratteristica visiva, penalizzata da un punto di vista cromatico. parlando con loro e a seguito di nostre esperienze professionali, ci siamo resi conto dei limiti delle interfacce (grafica, segni e colori per indicare un percorso) e di quanto studio e lavoro correttivo ci sia ancora da fare. un lavoro da fare non solo a loro favore affinché non risultino discriminati, ma per tutti i così detti “utenti” di un servizio pubblico. siamo dunque tutti coinvolti nei limiti e nella pochezza progettuale di molta comunicazione visiva. i criteri progettuali che sostengono la segnaletica orientativa di molte istituzioni risultano troppo spesso approssimativi, personalistici e inefficaci per qualsiasi utente che non abbia già fatto una certa pratica di navigazione in quella stessa istituzione; cosa che lo porta inevitabilmente a non sentirne più la necessità. scartando la paradossale ipotesi che detta segnaletica sia solo un’autocelebrazione istituzionale, risulta assolutamente logico che serva soprattutto per chi si avvicini per la prima volta alla navigazione in quegli spazi, per chi debba cambiare una certa rotta di navigazione per arrivare a una diversa meta e infine per coloro che sentano il bisogno di una rassicurazione, di un feed-back segnaletico che li affranchi dall’ansia di aver sbagliato percorso, nonostante conoscano abbastanza bene quel territorio di navigazione. 2. il daltonismo lo scopo di questo articolo non è quello di approfondire scientificamente il fenomeno del daltonismo, perché, come già scritto, i daltonici e i nostri studi relativi alle loro esigenze, ci hanno aperto gli occhi su una situazione in difetto per tutti. tuttavia riteniamo doveroso un accenno alle caratteristiche di questa anomalia cromatica. il termine daltonismo prende origine da john dalton, un fisico e chimico inglese che nel 1798 descrisse un’anomalia congenita della visione dei colori di cui era affetto lui stesso. gli individui con una visione “normale” dei colori sono detti tricromati normali. qui di seguito le variabili possibili che rientrano tutte nel termine di daltonismo. 3. il ruolo della sensazione cromatica (fig.1) in bianco e nero e scala di grigi ecco come si presenterebbe l’ambiente naturale, se lo potessimo vedere come è realmente; di seguito, come viene visto da un tricromate normale (tricrom), da un deuteranomale e da un deuteranope (deuteran). ma l’ambiente naturale, visto in tricrom o in dalton, non è discriminante. è l’atto percettivo che rende consapevoli di ciò che si vede e dei suoi significati. quando i significati vengono determinati attraverso determinati colori, come avviene spesso nella segnaletica e in molte convenzioni o normative tecniche, c’è la concreta possibilità che i daltonici vengano messi in seria difficoltà. ma, come scritto, succede che molte interfacce grafiche mettano percettivamente in difficoltà chiunque. la stessa fotografia (fig.2) di una rana, elaborata nelle diverse visioni (da sinistra verso destra: tricrom, protan, deuteran e tritan), dimostra che il colore è un elemento di “lettura e interpretazione” che assume un significato percettivo utile solamente se integrato nel contesto e che in natura non è strettamente indispensabile quanto lo è invece il contrasto chiaroscurale. il colore non è dunque elemento percettivo tale da poter essere utilizzato da solo, perché solamente se figura 1 14 cultura e scienza del colore color culture and science | 01/14 posto su una certa figura e con un certo sfondo e in un certo contesto è in grado di assumere un significato percettivo, ovvero interpretativo di ciò che si sta osservando. queste considerazioni appaiono del tutto naturali, ma nella cartellonistica vengono spesso ignorate e una società dove aumentano anziani, etnie e lingue diverse, sarà necessario un cambiamento di approccio più rivolto al percettivo. si aggiunga poi, e non è cosa da poco in un gruppo sociale complesso come quello che frequenta i grandi ambienti pubblici, che la percezione della scena cambierà a seconda di chi è l’osservatore, quale è il suo ruolo, quale compito ha da svolgere. 4. il colore e i daltonici il colore è una sensazione creata dal cervello a seconda dell’intensità e della qualità spettrale della luce che arriva ai coni retinici, dunque i daltonici hanno semplicemente sensazioni diverse da quelle dei tricromati normali. il fatto che tale anomalia sia stata scoperta da dalton nel 1798, dimostra per quanto tempo sia stata ignorata e ben poco influente sulla vita e le attività dei daltonici. compatire un daltonico perché non può vedere i “bellissimi colori della natura” è una ingiusta e patetica discriminazione; per lui il mondo è bello così come lo ha sempre visto. la rivoluzione industriale ha introdotto moltissimi sistemi artificiali nell’ambiente antropizzato. sistemi tecnologici guidati da convenzioni e normative con interfacce frequentemente basate sulle differenze di tinta. il rosso e il verde tra le prime e proprio quelle che la maggior parte dei daltonici (deuteran e protan) confondono. ma non è la convenzione del semaforo a render loro difficile il relazionarsi con gli altri, infatti, subito dopo aver visto e riconosciuto comunque la luce bianca al posto del verde e gialla al posto del rosso (per i deuteran), suppliscono con una convenzione collegata: “la luce è di un semaforo; normalmente il rosso è sempre in alto, ma può anche succedere che sia il primo a sinistra (nel caso di un semaforo orizzontale)”. ma è in molte altre situazioni dell’ambiente antropizzato, quello delle relazioni e dei compiti da svolgere, che le cose si complicano. spesso si ritiene erroneamente di poter utilizzare il colore come indicazione prevalente, secondo normative convenzionali le più disparate, che non solo non considerano il mondo dalton, ma nemmeno la problematica percettiva dell’utente qualsiasi, frequentemente costretto a dover apprendere velocemente le più diverse interfacce delle molte istituzioni, magari confezionate con gusto estetico, di buon design, ma spesso inadeguate dal punto di vista percettivo. 5. l’inadeguatezza di percettilitá di molta segnaletica quella che noi definiamo inadeguatezza di percettibilità è in sintesi: •la scarsa affordance dell’indicazione (difficile comprendere se si tratti o no di un indicazione), •la difficile comprensione dell’indicazione (che cosa mi sta indicando, che significato ha), •la difficile memorizzazione dell’indicazione (se la dimentico non riconoscerò o confonderò un suo richiamo successivo), •la difficoltà nella discriminazione dei diversi tipi di indicazione (ci sono sempre delle gerarchie, come capirle?), •la difficoltà nel comprendere a chi si rivolge l’indicazione (mi riguarda per il compito che ho da svolgere oppure è destinata ad altri compiti o agli addetti dell’istituzione?) quale può essere dunque il modello al quale ispirarsi per trovare parametri da studiare e sviluppare per un progetto più corretto delle interfacce? 6. il modello percettivo al quale ispirarsi l’essere umano è biologico e si è sviluppato all’interno di un mondo biologico: l’ambiente naturale.[1] le caratteristiche dell’ambiente naturale figura 2 1501/14 | cultura e scienza del colore color culture and science boscoso nel quale il sistema visivo e percettivo si sono sviluppati [2] sono l’esempio emblematico di quanto sia importante la diversità che si manifesta tuttavia con un’apparente serialità, ma grazie alla quale l’essere umano riesce tuttora a orientarsi e a comprendere ciò che gli è utile per il compito da svolgere. in un ambiente artificiale, come negli interni di un grande policlinico, il contesto, la scena, deve dunque offrirsi alla percezione con elementi di continuità, ma anche di diversità e riconoscibilità come avviene per la scena naturale. gli apparati segnaletici orientativi dovrebbero essere organizzati per categorie orientative in modo da adattarsi ai diversi ruoli e compiti da svolgere di un utenza molto diversificata. 7. la nostra bozza per il sistema segnaletico orientativo per il nuovo ospedale di alba-bra riteniamo importante organizzare la segnaletica orientativa secondo categorie prioritarie di ricerca e utilizzando pittogrammi facilmente riconoscibili e memorizzabili, differenziati, nelle diverse categorie, per restituzione grafica, colore, colore del fondino e forma del fondino (fig.3). per l’utente dalton, ma anche tricrom, dovrebbe risultare molto più semplice e veloce trovare, tra le tante, l’indicazione da seguire per espletare il proprio compito (per esempio: recarsi nel reparto dove è ricoverato un congiunto). 8. conclusioni partendo dalle esigenze orientative e di lettura delle interfacce dei daltonici, vogliamo, con questo contributo, avviare un processo di ricerca applicata per migliorare i sistemi segnaletici di orientamento anche a vantaggio dell’utenza tricromate. crediamo di aver dimostrato l’insufficienza dell’uso dei colori se non opportunamente contestualizzati e supportati da diverse forme e segni grafici e di avere, in tale modo, stimolato verso nuove attenzioni e professionalità per rendere più efficienti tutti i sistemi strutturati di servizio sociale. note le elaborazioni delle immagini in versione dalton sono state realizzate da stefano de pietro, utilizzando un software di propria concezione sulle basi fornite da vischeck (http://vischeck.com/). essendo qui riprodotte in cartaceo o informatizzate in formati diversi, sono da considerarsi indicative. bibliografia [1] david h. hubel, “occhio, cervello e visione”, zanichelli editore, bologna. [2] lucia ronchi, “la scienza della visione dal punto di vista delle scene naturali”, fondazione giorgio ronchi, firenze. giulio bertagna, aldo bottoli, “scienza del colore per il design”, maggioli editore, santarcangelo di romagna (rn). figura 3 cultura e scienza del colore color culture and science 56 cultura e scienza del colore color culture and science | 03/15 1. introduction the creation of professional figures with very transversal competences, able nevertheless to maintain a profile with a recognizable identity that is appealing for the world of work, is a challenge that anyone involved in training has to deal constantly. the global crisis, coupled with a growing necessity of flexible figures, with competences so that they are not confined in steady positions, is making the creation of didactic programs an activity more difficult than in the past. to this premise, we must add the boom of new technologies, that in the last years changed radically the way of working in term of request, products, management, and more. moreover, there are issues (concerning the creation of a learning path) that become crucial, when the graduate student cannot be accredited in professional bodies such as architects or engineers. these issues are usually related to the perception of the professional figure created by the course: by the candidates (in terms of expectations) and by the world of work (in terms of competences needed for certain positions). in this contribution, i will focus on a didactic process thought for two specific professional figures, the lighting designer and the color designer. i will describe briefly two specializing masters: the lighting design & led technology held by laboratorio luce of the department of design, politecnico di milano, and color design & technology held by lab. luce and università degli studi di milano. 2. building a professional the main purpose of these two master programs is to create figures that can enter the world of work from the very moment they finish their training. this is a direct consequence of the lack of academic degree programs specific to these two disciplines. manufacturers and studios that have in the design of light and color their main activities, usually have to undergo a long process of internal training for students that come from “classic” faculties (usually architecture, engineering and design), where these subjects are handled in a very academic way or with very little depth. the master in lighting design at the politecnico di milano exists since 2004 (with a previous program held in 1988) and evolved greatly in the eleven editions 1andrea siniscalco andrea.siniscalco@polimi.it 1 department of design, politecnico di milano didactic for building professionals. the experience of lighting design and color design masters figure 1 students attending the first lectures of the eleventh edition of the master in lighting design & led technology didactics 5703/15 | cultura e scienza del colore color culture and science that went through. this evolution in the program came directly by the continuous dialogue between university and the world of work. lighting design studies, with their interventions have helped to give a very practical, project oriented direction, and companies, over the years, helped defining the program by communicating the subjects that in their opinion, were the most useful in order to work in their technical offices. the process to obtain a program balanced between the many souls of this professional sector required to find an appropriate balance between technical skills and culture and communication. in addition to that, participants have their own personal idea to what their future profession should be. the specializing master in color design is more recent and can count only one edition, but the experience maturated in the lighting design sector allowed the two universities to find an effective program straight away. the world of work has indeed proved to be very receptive to these professional figures so that the requests for graduated students are much higher than the available candidates. 3. fundamentals the definition of a competent professional begins obviously with the basic competences of the subject, the technical tools through which the creativity of the future designers will express at best. the program of the two masters are different regarding the subjects that are proposed. 3.1. master in lighting design & led technology theory and technology of light study of natural light, how it can be measured and how it affects perception of architecture. electronic components and leds is a central subject on the master and focus (in multiple lectures spread on the whole duration) on how to control these new technologies in terms of light sources, optics, power supplies and control systems. there are then experiences with the measuring tools, in order to give a better understanding of the physical quantities of light. methods and tools of light planning the subject mainly known as illuminating engineering in which the main unit of measure and the relation between them are described. this very technical subject help the students to be quick minded when they approach the design; being able to understand the mathematics behind light in order to not just rely on software simulation. cad for lighting coupled with illuminating engineering, usually we present a professional lighting software to students, so that while they learn the relation between light quantities, they acquire a tool to speed up the verification of their projects. other than the presentation of the interface and functionality, various real life exercises are proposed to students. culture and practice of lighting design in this modules students deal with art, not only the so-called light art, but the traditional arts as well. how light is portrayed by artist in the centuries so they can steal from the most famous artist and enrich their sensibility for light. another important aspect presented is science of perception; the mechanism that affect the process of vision from an optical, physic and psycho-physiological point of view and how these effects can be used effectively in a project. there are then a series of seminars with professionals, which bring their experience by describing their more challenging and interesting works. didactics 58 cultura e scienza del colore color culture and science | 03/15 3.2. master in color design & technology perception and color history culture and color history and the aspects of perception that are the basis of its complexity. the perceptual mechanisms that affect the color and vision in general are presented to enable the students to recognize and design them. colorimetry and color systems color is a subjective characteristic, but colorimetry is needed to measure, standardize, communicate and represent in an accurate way the color of a surface or a light source. the theoretical basis of perception, colorimetry, photometric and radiometric measures are presented in this module as well as the color atlases, an alternative way to select, represent and communicate color. this module gives the essential technical skills that are the basis of the color designer, independently on the application areas. students are also encouraged not only to understand the laws that govern, i.e. a spectrophotometer, but also to learn how to use it correctly. digital color with the diffusion of new technologies, more and more aspects of communication and color reproduction are becoming digital. this module presents theoretical and practical fundamentals for manage, view and reproduce the digital color applied to different media, with particular attention to the limitations and problems associated with the use of different devices and color profiles. color applications this module resumes how the knowledge acquired in the previous modules can be applied in most professional fields and applications, through examples and case studies deriving from different contexts: marketing, visual communication, restoration of cultural heritage, photography, architecture, product and lighting design and more. 4. project works once the students acquire the basic tools for the project, they must learn a design method. as already stated, however, these competences are very transversal. professional realities that require these skills may be very different from each other. in order to provide a more complete frame to the students, professionals and manufactures of the sector intervene in the lectures to manage designing experiences (usually lasting three weeks) called project works. each project work is dedicated to a specific field of the subject, and students organized in teams, must develop a case study from the concept to the executive drawings, reviewing the process with professionals and exposing their projects in a final dissertation. these modules are different for the two masters as well. figure 2 students of the color design & technology master improve their competences with color systems and measuring tools. didactics 5903/15 | cultura e scienza del colore color culture and science 4.1 master in lighting design & led technology lighting for retail purposes students have to design the lighting for commercial spaces, where the importance of the object and the brand is essential. the classification of selling points (high range, shopping centers, etc.), and identification of the requirements and the specific peculiarity of the project in various cases. identification of the key element of the space dedicated to the sale: cash counter, vertical display case, wall objects, dressing rooms, waiting lounges, and all of the various lighting solutions that may be implemented. lighting for urban environment lighting for exteriors, not only intended as streets, roundabouts, tunnels, but mostly areas of urban interest, where lighting can contribute radically to urban beautification, safety and energetic sustainability. building facades, squares, and everything that can be improved with the use of proper lighting. lighting for the show the world of lighting for theater and live stage is richly evocative, and the aims of the lighting designer are quite different from the architectural field. how to create suggestions in theater, a cue list for a live concert. all the lighting components (products, technologies and the control protocols) and the history of the show business are described in this module. the emotional component of this module is essential to students to understand how to improve even their architectural/technical work, giving them more depth. lighting for cultural heritage cultural heritage not intended only as museum lighting. everything that has to do with the heritage of human beings, such as monuments, historical sites and facades, monuments and so on. all the lighting solutions that suits better the requirements of this delicate field (color rendering index, protection of the goods, etc.). lighting for hospitality how to manage light in the spaces intended to host human beings. multiple environments can be subject of this module, from hospitals to hotels, from convention halls to restaurants or cruise ships. the use of light and new technologies for the purpose of the temporary stay of individuals. figure 3 students of the tenth edition of lighting design & led technology master attending a lecture of giovanni pinna at caly paky show room. didactics 60 cultura e scienza del colore color culture and science | 03/15 4.2 master in color design & technology color for communication function and communicative dimension of color within the project of communication design. each communicative artifact arises from a series of choices that fit into a well-defined design process. the design and implementation of a brand start from the visual identity (name, brand, logo, lettering, packaging, integrated communication) that ensures the recognition and affirmation of the company. it is clear the importance of color in this strategy: the visual identity is built on the evocative and persuasive aspects of the chromatic language. color for fashion design study of the color texturing in fashion with the aim of being able to offer the same product with different color variation, in order to reach culturally different markets and to offer the sensation of a personal choice to individual consumers. starting from the construction of the color palette composed by individual colors, for the fashion collection, combined in two or three main approaches in relation to the messages conveyed their aesthetic and social characteristics. color for interior design this module is dedicated to the analysis of the application possibilities of a chromatic design, for the creation of innovative retail spaces, which can ensure a harmonious relationship, with the values from the image communicated by the brand and corporate identity. color for industrial product design the aim of this project work is to develop a methodology to design through the simulation of a cmf project (color/material/finishes) of a real product. the students go through all of the methodical phases needed for the definition of the identity of the product: study of the market (position, competitors…), study and definition of the target, study of cmf trends in the sector and creation of cmf scenarios. color for urban space explore the close relationship between architecture and urban space and the aspects related to the interaction between the human being and the natural environment. the role of the “perceptual project” for the growth of civic and urban identities is highlighted. the module examines the issues related to the phenomena of perception and color in the urban scale by providing theoretical and procedural tools with the support of pictures, cognitive maps and case studies. 5. professional empowerment and internship many hours of both the master programs have been dedicated to the professional empowerment. some of the companies and professionals willing to host interns at the end of the front lectures came in the classroom to tell their story and explain why figure 4 project work “color in urban spaces” teachers giulio bertagna and aldo bottoli. work of salma hussein and tanja polegubic. didactics 6103/15 | cultura e scienza del colore color culture and science there is the need of field expert. they also brought products, devices and materials to show to the students. moreover, visits were made to companies that opened the doors of their laboratories, test sites and technical offices. the final phase of the didactic path of both masters for all of the students is the internship. more than one hundred realities agreed with the didactic programs by giving their availability to host interns in their offices. the students can express preferences on where to go. the internship last for a minimum of 312 hours and it’s a fundamental phase for the students because allow them to use the acquired skills in a professional environment, learning a specific methodology that can be different from a manufacturer, a theater a studio or other realities. the professional figure that emerges from this learning path is innovative, and with enough flexibility to satisfy the needs of the world of work. didactics figure 5 – students of the seventh edition of the master in lighting design & led technology visit the factory of disano, one of the companies that collaborated with the master and hosted interns. _goback _goback _goback _goback _goback _goback _goback _goback _goback _goback cultura e scienza del colore color culture and science 4 cultura e scienza del colore color culture and science | 04/15 1rossella catanese rossella.catanese@uniroma1.it 1dipartimento storia dell’arte e dello spettacolo, sapienza università di roma repainting the mechanical ballet. restoration of colours in ‘ballet mécanique’ by fernand léger 1. introduction this paper comes from a research [1] carried out two years ago during the haghefilm foundation internship programme. haghefilm foundation was a non-profit international organization created by the laboratories haghefilm conservation in order to improve research and support activities related to techniques and technologies of film preservation and restoration [2]. into this framework, haghefilm foundation’s main goal was to promote results of the research, but this often leads to deal with copyright holders instead of screening and proposing experimental researches in educational contexts just for free knowledge. 2. film restoration since the eighties of the last century, after unesco conference [3], film has been institutionally considered as cultural, rather than a commercial item. it has been given a systematic, academic and ethical disposal to film conservation and restoration practices. films required conservation policies and cold storage for their structural fragility [4]. they have got a number of unchanged features and other elements that we have tried to “improve” in order to preserve them. the films have a part called photosensitive emulsion, from the early years, when the supports were made of flammable cellulose nitrate films, and then when they were made of safety (non-flammable) cellulose acetate, until polyester bases introduced in the eighties and currently used in the productiondistribution market. this emulsion may have a wide range of components, including salts such as silver nitrate or chromogenic couplers in the emulsions of colour film, but it is interesting to know that the function of emulsifier is given by the gelatine, an organic product. this “organic” dimension in the film, susceptible to degeneration, further guarantees its syncretic charm. film is therefore an art that tremble of vivid emotions and has got in its own materials an animated, living element. restoring an audiovisual text is always an operation on the formal setting and every different medium introduces different formal connotations. the restoration of an audiovisual support is the re-formalization and the reactivation of the text according to its structure, examination of the text and of its gaps, hermeneutic activity which consents to recreate an identity opening to possible further interpretative operations [5]. actually restoration is always an exegesis work, deep-rooted in practice, but there is always a philological research, exploring efficient methodologies to understand and interpret the work. the problem of modernity, as historical dialogue and methodological customs, is a basic principle in any restoration. in fact resetting a text is always a dialogue with a past, near or far, and it becomes a comparison between two different ages. every restoration is a liaison with a memory. a useful definition for the audiovisual restoration is proposed by paolo cherchi usai: «restoration is the set of technical, editorial and intellectual procedures aimed at compensating for the loss or degradation of the moving image artefact, thus bringing it back to a state as close as possible to its original conditions» [6]. the audiovisual support is radically different from the artistic unicum, so also the idea of original can change if you consider a philological-textual level or a material level. it will be different also the gaps treatment: the video, as film and photography, has got intrinsically the concept of copy, related to the idea of technical reproducibility, giving also a different perception, not one and synchronous. the introduction of the numeric information among the images system allowed a wide flexibility of action on images, but a digital medium implies a trans-coding process which uses calculation by discrete, discontinue values, turning light waves into numeric units (from digit = decimal number). even if digital system is a completely different structure of representation, these media are now in a transition age [7]. thorburn and jenkins wrote: «in our current moment of conceptual uncertainty and technological transition, there is an urgent need for a pragmatic, historically informed perspective that maps a sensible middle ground between the euphoria and the panic surrounding new media […]» [8]. 504/15 | cultura e scienza del colore color culture and science digital technology ensures data repeatability without alterations and a high potential of intervention on data. the technological advances, as the realisation of processors and more powerful computer buffer, make the digital arriving in cinema in higher standards. 3. a case study: ballet mécanique 3.1 the film the eye film institute decided to commission the restoration of its hand coloured copy of ballet mécanique (1924), fernand léger’s masterpiece of the european twenties avant-garde, with kiki de montparnasse, dudley murphy and katherine murphy. for eye, the restoration lab haghefilm acquired a 2k digital scan in order to produce a digital intermediate for both the colour and the black and white parts (requiring positive editing for the projection prints). but another experimental project has been proposed, i.e. to produce another, unique black and white positive copy with hand-painted or tinted sections matching, as closely as possible, the original nitrate. my duties consisted in running colour tests under the supervision of paolo cherchi usai, ulrich ruedel and daniela currò. furthermore, i pursued research about the history of this film and its moot authorship. sought by many film archives in all the world (new york, paris, mexico, montreal, bucharest, havana, london, münchen, wien, berlin, los angeles, berkeley, belgrade, stockholm, turin, cambridge, washington, canberra, roma, ottawa, copenhagen), there are several versions of ballet mécanique. according to giovanni lista, this film has to be regarded as a work in progress, whose drafting continued for years, without an original [9]. the nitrate coloured print owned by the dutch filmmuseum came from property of filmliga, a cultural association born in 1927 in amsterdam, focused on the collection and the diffusion of avant-garde movies; it had a great season between the 1928 and the 1930, and broke up in the 1931. then the collection of the association has been acquired by the filmmuseum, that still keep those films and among them ballet mécanique [10]. lawder defined ballet mécanique as «the classic example of a fully developed painting aesthetic transposed into film by a modern artist» [9]. the film is one of the most contested artworks of the twentieth century. its genesis involved different persons: fernand léger, dudley murphy, man ray, ezra pound, georges antheil. every one of them worked on the film giving an artistic contribution. it has been a collaborative work but the question of the authorship is still now open to debate. some art historians and film scholars have different interpretations: standish lawder considers léger as the creator, and murphy as an assistant; judi freeman and susan delson emphasize the crucial contribution of murphy and involves man ray in the authorship. william moritz minimizes léger’s contribution, ascribing the creation mainly to murphy and man ray [1114]. in the earliest known print of the film, the opening credit reads “f. leger and dudley murphy present ballet mechanique”; and léger’s notes on the film, prepared as it was nearing completion in 1924, call it a “film by fernand léger and dudley murphy” [14-15]. in ballet mécanique’s film credits murphy’s contributions disappeared. neither man ray nor pound nor antheil was even appointed. man ray in his autobiography self portrait affirmed: «and that is how dudley realized the ballet mécanique, which had a certain success, with léger’s name» [16]. 3.2 the restoration project haghefilm scanned both the dutch 309m positive nitrate copy, coloured, and the cinémathèque française 291m positive black and white print, in order to get the best results comparing editing and sequences; the french 291m copy is denser, darker and less clear than the dutch one, probably because the french print comes from later generation elements. the editing order is slightly different. even if it is black and white, the french copy presents sections coming from a coloured source, with clearly denser frames. i checked the entire dutch copy shot by shot and frame by frame and i wrote accurate descriptions about the content of the shots, the frame-counting, the evenness of saturation, the kinds of applied colour, the splices and the damages. i found that every tinted section has been spliced and a lot of hand-painted sections were not spliced, but directly painted with many overlappings of colours at the frame lines. according to paul read, during the handpainting period the dye used for hand colouring were quite similar to those used for tinting: paints or acid dyes in water, they were absorbed easily by the gelatine of the emulsion side [17]. then we attended the digital grading. the filmmuseum asked for a higher contrasted look in order to recreate the shocking effect of that famous and charming avant-garde feature. the experimental project proposed by filmmuseum provided us with the opportunity to paint the coloured frames like they look on the nitrate copy. in the chemical lab of the haghefilm i have tried many different tinting experiments in order 6 cultura e scienza del colore color culture and science | 04/15 to learn how to work with tinting processes. i ran 62 tests in tinting and hand-painting, testing hues, concentrations, dipping time, mixtures, applications. but the positive black and white print made by the digital intermediate presented a bad grey density which, overlapping the applied colours, looks quite different from the original. we thought it was possible to work digitally taking out the colours and the brushstrokes, in order to underline the black and white image and to get a clear and vivid picture where applied colours could be visible and faithful to the original. basically using the hue/saturation software tools for the rgb channels might work like a “reverse filter” for showing the colour subtraction. in this process, theoretically correct, we were not aware that the applied dyes were not pure colours. furthermore, we did not consider the overlapping of colours, which mixes hues regardless of the frame line. some colour data were mixed in the brushstroke marks and we were able to find it by looking at the magenta sections visible in the red frame, also visible by the blue channel. so we thought to compare the coloured sections, triangles and circles, of the dutch copy with the ones seen on the black and white french element, in order to use those sections in the new black and white print that we will have to paint and tint. those sections have been already scanned and we checked frame by frame analyzing the two copies in comparison and producing a new record about the differences. many sections have been taken by this element reducing the digital intervention in compositing and the time spent in the digital work on the singles frames. this restoration has not been finished: one of haghefilm’s requests (improving of research on film restoration and dissemination of its results) was that the hand coloured print of the film had to be made available by eye to the haghefilm foundation for exhibition in educational, research, and outreach activities with mention of eye as the source of the material. eye could not agreed to this claim because of the “copyright dilemma”: the dutch cinémathèque can’t assign anyone the right to show the print because it doesn’t own that right, which is true for almost every film they preserve and restore. in some cases, like the so-called “orphan films” (works that have been abandoned by its owner or copyright holder), it wouldn’t have been a problem, but in the case of ballet mécanique it actually was, because it is a film were the right holders are very well known, so it was impossible for haghefilm to get the aforementioned rights. of course this negative event should be a chance to think about the mission of films restoration, about the free spread of research and its results. 4. conclusions i believe that this unique experience will be useful to understand how to balance the digital technologies, helpful and favourable to get the best achievements, with the traditional and fashionable applied colours, rediscovered example of how film arts has been close to the fine pictorial art. bibliography [1] r. catanese, lacune binarie. il resamaranta2015 tauro dei film e le tecnologie digitali, bulzoni, rome, 2013; r. catanese, g. edmonds, b. lameris, hand-painted abstractions: experimental color in the creation and restoration of ballet mécanique, in «the moving image» vol. 15, number 1, spring 2015, pp. 92-98. [2] g. m. paletz, the finesse of the film lab: a report from a week at haghefilm, in «the moving image», vol. 6, number 1, spring 2006. [3] unesco conference, belgrade 27th october 1980. http://portal.unesco.org/en/ev.php-url_id=13139&url_ do=do_topic&url_section=201.html (last visit in 06/08/2015). [4] c. frick, saving cinema. the politics of preservation, chicago, oxford university press, 2011; [5] p. bertetto, l’eidetico, l’ermeneutica e il restauro del film (1991), in s. venturini, il restauro cinematografico: principi, teorie, metodi, campanotto, udine, 2006, pp. 104106 [6] p. cherchi usai, silent cinema. an introduction, british film institute, london, 2000, p. 66 [7] g. fossati, from grain to pixel. the archival life of film in transition, amsterdam university press, amsterdam, 2009 [8] d. thorburn and h. jenkins, rethinking media change: the aesthetics of transition, mit press, cambridge, 2003, p. 2 [9] g. lista, léger scénographe et cinéaste, in id., fernand léger et le spectacle, editions de la réunion des musées nationaux, paris, 1995 [10] g. manduca, la lavandaia sulle scale. una nota filologica al ‘ballet mécanique’, in p. bertetto e s. toffetti, cinema d’avanguardia in europa, il castoro, milano, 1996 [11] s. lawder, cubist cinema, new york university press, new york, 1975, p. 65 [12] j. freeman, bridging purism and surrealism: the origins and production of fernand léger’s ‘ballet mécanique’, in r.e. kuenzli, dada and surrealist film, locker & owens, new york, 1987 [13] s. delson, dudley murphy, hollywood wild card, minnesota university press, minneapolis, 2006 [14] w. moritz, americans in paris: man ray and dudley murphy, in j.-k. horak, lovers of cinema: the first american film avant-garde 1919–1945, university of wisconsin press, madison, 1995, pp. 118-136 e p. 199 [15] published in the original french in «l’esprit nouveau» 704/15 | cultura e scienza del colore color culture and science no. 28, undated (most likely november or december 1924) [16] man ray, self potrait, little brown, boston-toronto, 1963, p. 218 [17] p. read, ‘unnatural colours’: an introduction to colouring techniques in silent era movies, in «film history», vol. 21, no. 1, pp. 9-46 cultura e scienza del colore color culture and science 3101/14 | cultura e scienza del colore color culture and science universi creati dai computer che propongono una realtà sintetica. le nuove generazioni crescono nell’esperienza quotidiana degli schermi e dei videogames, adattando la vista e l’attenzione ora a luminescenze intense e intermittenti, ora a rappresentazioni fantasiose. questi universi richiedono una immersività parziale o totale e provocano la necessita di una nuova definizione culturale dei loro colori. un colore sintetico, frutto della divisione della luce in rgb e della sua ricomposizione nell’occhio, che sposta il piano dell’apprendimento cromatico dalla sintesi sottrattiva a quella additiva, dalla materia alla luce. una luce colorata usata per simulare cieli artificiali e invitare a viaggiare in uno spazio immateriale, sconfinato, irreale. 3. natura versus cultura la visione culturale del colore consente di formulare categorie cognitive. il suo schema linguistico e mentale deriva dalla sua esperienza sensibile e si attualizza in continuazione, appropriandosi degli elementi di innovazione. sono note al proposito le ipotesi di brent berlin e paul kay (1969) per i quali il dato conoscitivo e nominale del colore viene organizzato secondo una progressione culturale di tipo evolutivo e, quelle di giorgio raimondo cardona (1985) per il quale abitudine visive diverse, dettate dal contesto, sviluppano sensibilità e quindi tassonomie differenti.la percezione dei colori è dunque una facoltà in movimento, soggetta a momenti anche di forte evoluzione e cambiamento. noi pensiamo che l’introduzione quotidiana dei cyber colori nel processo cognitivo, solleciti la ridefinizione delle tassonomie cromatiche e di senso, il cui processo, già iniziato, sta conducendo ad esiti ancora da analizzare sistematicamente. concettualmente il punto di partenza della riflessione che proponiamo isi può far risalire a quando l’umanità ha iniziato a osservare, scoprire, studiare e fabbricare le sostanze coloranti, per intervenire sulla realtà, modificandola. il passaggio da uno stato di natura a uno di cultura è stato evidenziato anche dal rivestimento cromatico di quanto costruito 1. nuove comunitá, nuovi colori nel nostro studio sulla storia dei colori dell’abbigliamento dai latini al xx secolo (1997), condotto per comprendere i motivi materiali, sociali, commerciali e ideologici che hanno caratterizzato e caratterizzano il gradimento collettivo per determinate gamme cromatiche, in specifici periodi storici, ci eravamo imbattute nel fenomeno dei colori digitali. verso la metà degli anni novanta particolari gruppi sociali, come gli artisti o i movimenti spontanei sub-culturali, si erano mostrati affascinati dalla qualità luminosa dei colori digitali, adottandone la nuance fluorescente per la sua componente simbolica artificiale, allusiva di mondi immateriali, tecnologici, di quella rete sconfinata senza luogo né tempo in cui si stavano formando le comunità cyber. cyberpunks e technos avevano introdotto dei colori acidi, fluorescenti e violenti nei capelli, nel trucco e nei tessuti, mostrando la loro rivolta contro la natura. colori aspri e corrosivi, funzionali alle luci dei mega concerti, che trovavano nelle fibre sintetiche, nelle plastiche e nelle finte pelli il supporto d’elezione, adatto ad accendersi di bagliori artificiali nell’intermittenza spasmodica dell’illuminazione delle discoteche e dei ritrovi notturni e a pulsare violenti a ritmi ripetitivi e parossistici della techno music. il tema ci ha affascinato e abbiamo continuato ad occuparcene, anche perché nel frattempo i colori digitali hanno invaso la comunità negli spazi lavorativi e in quelli di svago, in quelli pubblici e in quelli privati, diventando una presenza imprescindibile dell’ambiente artificiale (nella sua accezione di ambiente costruito). 2. dal mondo digitale ai cyber colori abbiamo pensato di chiamare queste gradazioni cyber colori in omaggio a william gibson (1986). non pensiamo che i colori digitali svuotino di significato i colori materiali, ma vogliamo porre l’accento sull’importanza della loro presenza nel panorama cromatico e sulla loro capacità e forza di creare nuove tassonomie di senso. la definizione di colore cyber introduce negli renata pompas lia luzzatto www.color-and-colors.it colori cyber abstract il lavoro si propone di illustrare il mutamento culturale e comunicativo che è avvenuto da quando il colore ha assunto un aspetto brillante e luminescente a imitazione degli schermi retro-illuminati dei computer. 32 cultura e scienza del colore color culture and science | 01/14 dall’uomo, segno e simbolo del suo dominio e della sua differenziazione. l’ultimo di questi grandi momenti, prima dell’era informatica, è stato quello della produzione industriale e della diffusione massificata dei colori chimici: una rivoluzione percettiva che dapprima ha sorpreso e poi abituato l’occhio e la mente alla novità di gamme cromatiche inusuali e alla loro fissità e inesauribile riproducibilità. se a metà del xix secolo il mercato tessile fu invaso dal malva sintetizzato dal chimico inglese william perkin, ottenuta trasformando gli scarti del catrame minerale, nel 1935 fu l’italiana elsa schiapparelli, la sarta amata dagli artisti, a mettere a punto una nuance ciclamino intenso, chiamata rosa shocking. più tardi l’artista francese yves klein, mise a punto nel 1956 insieme al chimico parigino edouard adam un blu oltremare estremamente saturo e luminoso, di cui brevettò la formula chimica con il nome di ykb, international klein blue, nel 1960. in seguito lo studio dei coloranti, delle tinture e delle vernici, non ha conosciuto sosta, ed è stata immessa sul mercato una varietà estesa di tonalità lucide, translucide o trasparenti; con particolari luminescenze e rilucenze. colori fosforescenti, fluorescenti, gamme fotosensibili, e termosensibili. colori con apparenza metallica, per conferire l’aspetto oro, bronzo e argento; tonalità con mutevolezze cangianti e opalescenti per avere riflessi a due fiamme; colori specchianti che comunicano il senso della variabilità. 4. dai colori della materia ai colori della luce il percorso che ha condotto il colore dalla materia all’immaterialità è avvenuto con la sua riproduzione tramite la frammentazione in pixel. gli schermi digitali, che esercitano un controllo matematico sull’emissione del colore, spostano l’asse della visione dall’unità alla divisione, dalla sostanza alla luce. mentre le colorazioni chimiche avevano rivestito l’ambiente costruito con una patina superficiale stabile ed omogenea, uniformando l’aspetto degli edifici, dei muri, dei locali, degli arredi, degli oggetti e dei tessuti; i colori digitali provocano un adattamento contrario e sollecitano l’adeguamento a un panorama cromatico all’insegna dell’immaterialità. il colore digitale crea un flusso colorato luminoso, mobile e perturbabile che conduce, attraverso gli schermi, in un mondo cromatico parallelo, sovrapposto a quello reale. un colore fluttuante e impalpabile, liberato dalla presenza di un supporto oggettivo, che muta l’ordine della percezione sensoriale. per la prima volta nella storia dell’umanità possiamo guardare immagini costruite solo con i colori della luce, estranei alla materia. il colore diventa così soggetto, forma, movimento, azione. già nel 1968 stanley kubrick in “2001: odissea nello spazio” rappresentò il travalicamento della quarta dimensione, con un’onirico e allucinato viaggio in un turbinio caleidoscopico di colori, essi stessi soggetto di esperienza. oggi la contrapposizione tra sostanza e apparenza, materialità e immaterialità, è superata dai colori digitali, fantasmatica presenza di soggettività simulate. ‘accendere i colori’ non è più da questo momento una metafora, ma un gesto che quotidianamente introduce i nostri occhi nello spessore illusorio degli schermi retro-illuminati, le cui possibilità senza limiti mutano le apparenze esteriori, che mentre costruiscono questa nuova realtà destrutturano la sensazione visiva, privandola dell’apporto degli altri sensi: del tatto, del gusto e dell’olfatto. in natura la formazione e la conoscenza del colore passa attraverso la materia e attiva la complessità di tutti i sensi che, nel ricordo, si fissano nell’immagine trasmessa dalla vista. nel mondo evocativo o immaginario degli schermi, il colore digitale passa solamente attraverso il senso della vista, e deve recuperare nel ricordo pregresso il suo collegamento con la polisensorialità, non più fisica ma astratta. noi crediamo che i colori delle immagini elettroniche chiedano un adattamento alle nuove informazioni cromatiche, uno scollamento dai riferimenti naturali e che, producendo un nuovo e diverso effetto di realtà, possano agire anche sul contesto, modificandolo. poter modificare i colori dello schermo, con una rapidità tecnica superiore a quella biologica, è sovversivo nei confronti della natura e del nostro rapporto con essa. sedici milioni di possibilità di colori limpidi, assertivi, brillanti e timbrici, sono una quantità ben al di sopra delle nostre capacità percettive e discriminative. l’universo dei colori luce e quello dei colori pigmento si fronteggiano e se in principio i colori degli schermi cercavano di imitare quelli della natura, oggi la chimica dei pigmenti cerca di imitare quelli degli schermi, con polimeri cangianti a multipla interferenza di colore. il linguaggio cromatico mutuato dall’esperienza digitale entra nel progetto allargato: dalla moda, al design, dalla pubblicità, alla grafica, dai fumetti, al cinema. così se il metallo era stato l’immagine e il simbolo della società tecnologica, il colore cyber è l’immagine e il simbolo della società digitale. 3301/14 | cultura e scienza del colore color culture and science 5. verso la formazione di nuovi simboli i colori degli schermi hanno generato e potranno ancora generare nuove codificazioni di senso. pensiamo per esempio al verde: naturale, ecologico, rassicurante, protettivo, perpetuo, che assume le valenze sinistre e inquietanti nei bombardamenti notturni trasmessi dalla televisione; o al verde che colora i siti web di ufologia, alludendo a esistenze aliene. pensiamo ai mutamenti comunicativi del rosa shocking, frivolo e sensuale, che assume nel cyber spazio una nuova valenza tecnologica, artificiale e prettamente digitale, indicando la qualità virtuale della visione. figura 1 tessuto con led, ditta lumigram sarl (francia) 34 cultura e scienza del colore color culture and science | 01/14 pensiamo al rosso che si trova frequentemente impiegato nelle zone delimitative della pagina web, come ad esempio nei frames e nei contorni alle immagini. un rosso che si assume, da solo, la responsabilità di tracciare i percorsi e le traiettorie della pagina, andando a richiamarle direttamente dall’inconscio dell’osservatore. infine arriviamo al blu, spirituale e affettivo, che si trasforma nel paradigma dello cyber spazio, come prima lo era di quello dello spazio celeste. nelle profondità virtuali di internet il blu, uno dei colori più diffusi, rappresenta l’universo da esplorare con la navigazione virtuale e assume la confidenza e l’autorevolezza necessarie a evitare il timore di perdersi nell’iperspazio. per concludere la nostra riflessione va anche al potere della rete, che si offre come lo cyber spazio navigabile del villaggio globale. in questo spazio colori e funzioni tendono a unificare linguaggi e simboli. il flusso della rete cancella i confini e crea contaminazioni tra le culture, produce eclettismo stilistico, indebolisce la coscienza del divenire storico, trasforma il tempo in un presente perpetuo e pone in declino quell’intensità che è propria di altri livelli più profondi di comunicazione. una comunicazione che abbrevia la durata del sentimento: così all’intensità dei colori digitali non corrisponde l’intensità delle emozioni. bibliografia [1] lia luzzatto e renata pompas, i colori del vestire. variazioni, ritorni, persistenze; hoepli, milano, 1997 [2] lia luzzatto e renata pompas, colore&colori; il castello, milano, 2009 [3] lia luzzatto, renata pompas, artificial environment, cyber space and new colours projects; in: color communication and management, ed. international colour association, ed. the colour group of thailand, bangkok (thailand), 2003. [4] lia luzzatto, renata pompas, dalla metafisica della luce alla luce oltre lo spazio fisico. viaggio tra antiche e nuove simbologie del colore; in: la psicologia del colore; ed. scientifiche magi, roma, 2001. [5] lia luzzatto, renata pompas, le mucche viola. risk, edizioni il clavicembalo, milano, 1995. cultura e scienza del colore color culture and science 34 cultura e scienza del colore color culture and science | 02/14 a printed code in the bottom right corner. during the exhibition every 3 days i chose a new colour name and painted it in the exhibition window and the person who chose the winning name won a tin of paint with their new name on it. approximately 600 people took part in it over a three-week period. all the names were catalogued and categorized and put into graph format. the graphs show all the colours in the library and how many people chose to name each colour. generally the most popular choices were blues and greens – perhaps this reflected the impact of the local environment, brighton is by the sea and the gallery is just a few hundred metres from the seafront. (figure 2) overall however one red was the most popular swatch chosen for re-naming, bs 6450 a bright red which 37 people chose to name with i am an artist and paintings conservator. much of my work focuses on colour and how this intersects science and art and language. through my work as a paintings conservator and my interest in historic and modern pigments i developed an interactive public engagement project called the ‘colour library’ as an empirical experiment for collecting and categorizing colour names. (figure 1) this was exhibited at fabrica gallery, brighton, uk, 2010. it is a small box with an exhibition window. displayed on either side of the window are a selection of household paint swatches from a high street paint manufacture. a complete spectral range of colours were chosen. members of the public are invited to choose a colour swatch from the sample selection, and rename it via a small paper document. all colour swatches are british standard colours (bs) with stig evans the portland colour chart figure 1 – public engagement project called the ‘colour library’ figure 2 3502/14 | cultura e scienza del colore color culture and science suggestions such as: ‘old sandals’ ‘almudena’s flower’ ‘small wonder’, ‘tantalising pink’, ‘peach beach’, ‘red rosy’, ‘dragons blood,’ arizona sunset, ’velvet red’, ‘st.jerome’s coat’, ‘dead coral bloom,’ ‘indian red,’ ‘portuguese soil,’ ‘wigan bricks,’ ‘delight,’ ‘chilli geranium,’ ‘clowns trousers,’ ‘costa rica sunset,’ ‘pale red crimson,’ ‘happiness day,’ ‘million blessings,’ ‘angel delight,’ ‘smush,’ ‘burnt pink,’ ‘coral,’ ‘retinal’, ‘capiscum orange’, ‘orgasmos,’ ‘dancing daddies,’ ‘wolf whistle,’ ‘skippy dies,’ ‘lady boy banging’. what became evident was that the results showed that the majority of names expressed by participants where similar in style and structure, corresponding to types of names that modern household paint manufacturers employ in labelling and selling paint to the public. here are some dulux examples ‘honey drizzle’ – ‘mystic mauve’‘emerald delight’‘golden bark’ ‘grecian spa’ , “caribbean dawn’ farrow and ball – ‘nancy blushes’, ‘dorset cream, ‘lulworth blue’, ‘elephants breath’, ‘smoked trout’ it made me wonder if this ‘consumeristic’ language has permeated our thoughts and ideas on colour and if it has affected our conscious and subconscious colour perception, consequently effecting our perception of the world. do we now assign these ‘consumeristic’ names to the natural objects in our world. it was american linguist benjamin whorf, who suggested that our language determines how we perceive the world. he said that because of linguistic differences in grammar and usage, speakers of different languages conceptualize and experience the world differently. i believe that since the time of whorf’s writing in the 1930’s, our colour language and vocabulary are now even more complex and varied than ever before. we now have a very sophisticated and elaborate colour language and terminology at our disposal. this is due largely to modern household paint and fashion industries, we as consumers are very accustomed to new and ever increasing and changing colour terminology from clothing to paint to pantones. in 2012 i had the opportunity to continue my investigations. commissioned by b side festival as part of the sailing olympics in dorset. ‘the portland colour chart’ was created for this event. based on the colour library this time i was interested to see if the public, when asked, would use colour names more specific to a place or area, rather than general ‘paint industry’ colour terminology that was apparent in the original colour library. (figure 3) the ‘isle’ of portland was a perfect location to undertake this project. the area has both rural and built up elements. it has a long and interesting history with many historic place names and with a small population of only about 12,000 . it has been relatively isolated for years. the first road to it was built between the wars, connecting to the mainland by one road only. the population has little migration/immigration and there is a distinct ‘separateness’ and pride in the local culture from residents. very different from the busy cosmopolitan city of brighton. a colour chart ‘base camp’ was set up at a site that marks the entrance and exit of portland in fortuneswell. 35 colours were chosen that were felt to represent the broad range of colours found on portland. participants were invited to choose three colour swatches from this set of 35 colours. they were allowed to take them away walk around the isle (you can walk it in half a day). they were encouraged to colour match tabella 1 – elenco dei materiali rilevati con l’indagine fors figure 3 – ‘portland colour chart’ 36 cultura e scienza del colore color culture and science | 02/14 them to the portland landscape, and afterwards, come back to the colour chart ‘base camp’. the users were asked to give names to the colours that specififcally related to portland. over a period 2 weeks 321 participants took part. results were documented in a large book. the results were counted and separated into specific and non-specific names. any name relating directly to portland was counted as specific; otherwise the names were categorized as non-specific. results showed that out of a total 321 names received 118 were non-specific and 203 were specific. which still shows about a third of people using non-specific names. the majority of these were again in the style of the paint industry names. examples for non-specific names: ‘turning tide’, ‘deep blue dive’, ‘stormy sea’, ‘navy blue,’ ‘beach hut blue’, examples of specific names: ‘deadmans storm,’ ‘the race,’ ‘viper’s burgloss,’ ‘portland blue.’ a chart was complied of the specific names and exhibited around portland and online at www. portlandcolourchart.co.uk (figure 4) in 2014 a commission from the maison de culture in amiens allowed for further colour langauge investigations, this time in french. ‘jardins chromatiques’ comprises of two sculptures made of solid oak and vitreous enamel colour swatches. as with the portland colour chart, colours were matched and chosen to represent the area. |the hortillonnages or ‘floating gardens is a 300 hectare area on the river somme next the city of amiens. the gardens have been cultivated since roman times and comprise of small plots of land separated by canals, access is by small boat only. the sculptures (figure 5) were positioned on two separate islands. signs on the reverse of the sculptures informed the participant how to engage with the pieces, qr code enabled users to access the “jardins chromatiques’ website and social media. the results were posted onto the website. www.jardinschromatiques.com over 2 months the website collected 87 names with a mixture of naming styles. many results were names relating to the area, however the majority, again, were similar to paint industry names but the terminology appeared to be less ‘romantic’ than the uk colour responses and more pragmatic. interestingly this corresponds to the pragmatic style in which the french dulux uses for its paint names. compared to the english names the french paint names are generally very matterof – fact, with names such as raspberry, strawberry, sea blue, emerald, pearl grey, dulux is the worlds largest house paint manufacturer and owned by ici they manufacture paints worldwide and a simple internet search will show how many countries ‘figure 4 portland colour chart’ 3702/14 | cultura e scienza del colore color culture and science this has inspired a series of photographs were i hold up a dulux swatch on a stick in front of the camera and match it to the surrounding colour. www.stigevansphotography.co.uk (figure 6) in conclusion although all three projects have not been rigorously implemented in a way that a scientific experiment would be, these initial data collecting experiments and artworks in colour naming show that the public are strongly influenced by contemporary paint and colour terminology. if our language does affect the way we perceive and categorize the world, as worf suggests then perhaps this consumer colour terminology is really affecting the way we view and experience the world. figure 6 blue seduction 3’ stig evans 2014 they sell their paints in (over 100),– it is interesting to note that although all the colours and their codes are identical worldwide, the colour names are different for many countries. however it is curious that italy is not on the list. looking through the various different dulux websites it is interesting to see the differences and similarities. for example a dulux blue for example (10bb 59/137) is called ‘amazon beat 4’ in the uk and south africa, in the usa -‘teton sky’, south america -‘ brillo estelar’. another dulux colour ‘36bb 46/231 is ‘blue seduction 3’ in the uk, in the usa‘elise’, south america – ‘aguas de lisboa’, south africa – ‘fragrant cloud 3’ and france – ‘cobalt 3’ ‘figure 5 cultura e scienza del colore color culture and science 5502/14 | cultura e scienza del colore color culture and science michela rossi michela.rossi@polimi.it dipartimento di design politecnico di milano color design in the bauhaus laboratory of wall-painting 1. introduction the project adopts the design as an intermediate tool between the concept and the building, using conventional codes to describe characteristics that cannot be exhaustively defined by their scale reproduction. which is why the symbolic and simplified representation in accordance to the standards developed by technical languages needs a specific expression of the characteristics that can’t be measured as a form or can’t be directly related to numbers. one of the qualitative elements of the project is just the color, that kind of rigorous identification is conditioned by practical difficulties. as a result, color seems to be the weak element in the expression of the project. the representation of color has been subject to long succession of attempts to be identified without any ambiguity, usually using references to mathematical models: geometric patterns, math coordinates, or numerical formulas. this type of approach can only marginally affect the tradition of architecture and interior design, where the graphical representations of the project witnesses a controversial relationship with the expression of color. in fact, unlike other qualitative elements, there isn’t such thing as a unique coding for the representation of color in project documents. the issue with identifying the exact color can be dealt with by adopting numerical coordinates in the color-systems or perhaps by referencing to the color-producers’ palettes that are partially unified at least in relation to specific design sectors (mainly pantone, ral, munsell); however, the real intrinsic problem is the control of the color throughout the intermediate stages of the project, in which the design and the representation serve as verification tools. the immediate consequence of these difficulties shows in the simulated and simplified control of the preliminary design process, causing a quite common tendency to postpone color choices to abstract representation is the weak element in color design. it actually seems to condition the expression of color in the project. the la always favored the design as a media between design and building, by the use of conventional codes and symbolic languages, which are able to unambiguously describe formal characteristics that couldn’t possibly be described in detail in the technical representation on scale. even for the representation of the color, there is a long tradition of attempts to obtain an unambiguous identification through geometric conventions, mathematical coordinates and numerical formulas, but this can only marginally affect the tradition of architecture and interior design. this is due to difficulties in reproducing the elaborate, which forced to use watercolor drawings (colored or otherwise) in the original. the effects of representation tools on the project, and therefore the possibility of remote control of the color, required an investigation of the color’s representation when it becomes a decisive feature in the characterization of the inhabited space and therefore a research element for architectural and interior design. with regards to the relation between color and design, the research of avant-garde artists of the early ‘900 is significant as the contribution of the painting played a decisive role in the general renewal of architecture and applied arts. in the crucial years of the birth of the modern movement, the activity of the laboratory of mural painting at the bauhaus reinforced the concept of color as an active element of “building”by replacing the ornament to emphasize the articulation of the constructive elements of the room. the research in design required the development of an experimental approach to the color representation, with a free reinterpretation of conventional drawing codes. the research aims to investigate how the lack of conventional references on the one hand, and, on the other, the cultural contribution of painting and interior decorating, encouraged the experimentation with new representation codes. 56 cultura e scienza del colore color culture and science | 02/14 the construction stage and directly on the site. this could be due to difficulties in the reproduction of technical drawings and to the high cost of multiple color drawings, which, before the diffusion of digital printing, required the use of original coloring of copies. the importance of representation instruments and the need of some kind of remote control on the developing of the design process, lead to the research of representation codes of color once it explicitly gained a decisive role in the characterization of the shape and of the room, becoming a formal element in design research. the research aims to verify how the lack of conventional references from one hand and the cultural contribution of painting on the other pushed towards experimenting with different representation codes, in which the graphical and geometrical concepts acquire a value that goes beyond their design content, with a special reference to the “constructive” or “decorative” concept of color in architecture and interiors. 2. color and decoration: the avant-gard and the design the color was always perceived as a finishing decorative element, such as the ornament. it had secondary, accessorial importance in relation to the building elements of the architecture. quatremère de quincy, when expressing his position on the subject in his dictionnaire d’architecture, defines it as “a finishing”, stating that the use of color can be a money-saving solution to replace plastic ornamentations, thus emphasizing the supremacy of the form on the color. this prejudice survived even after the rediscovery of original color in the monuments of classical antiquity, where the bright hues of pure primary color marked the hierarchical role of the constructive elements of the order: red along the main lines of the basic structure, blue on the secondary elements of the entablature (medallions and triglyphs), yellow in the decorative details of the frieze. [1] even semper [2] and ruskin implied its decorative concept as a surface coating of the wall, when they reevaluated the aesthetic role of polychromy. the influence of the critique is confirmed by the contemporary emphasis of the ornament painting in interiors, where the tempera simulated the most expensive wall dressing, forcing an implicit relationship between the painting of walls and the interior decoration, entrusted in the execution of skilled craftsmen whose education came from schools of arts and crafts. at the turn of the eighteenth and twentieth century, the dichotomy between major and minor arts, fig.ure 1 reconstruction of the achromatic painting of the kandinsky’s dining room in dessau (1926), designed by the students of the laboratory of mural painting at the bauhaus. the original design is a plan with walls at the floor opening to the sides of the ceiling, just like a child building a dice, in which the ceiling is the face with the number one. 5702/14 | cultura e scienza del colore color culture and science namely architecture and decoration being the “poor” daughter of painting, appeared in the identification of new professional abilities. later on, the formal renewal of the arts, started by the avant-garde, challenged the color as a result of the ornamental blaze of previous decades; at the same time, the leading role of the painters in the search for new formal canons lead to the rethinking of the color in architecture, as a possible answer to the elimination of plastic ornaments. architects, searching for a unity in between the arts, found a new way of characterizing the built space in the geometry and in the color, similar to what they had been doing for a long time. as a matter of fact, in a way, they became painters too. the color lost its previous reference to the decorative surface, becoming an elective element of architectural qualification. just after the end of world war i, bruno taut, who had declared his interest in the “composition of the color in the space” in 1905 before experiencing the use of saturated hues in the garden city of berlin-grunau [3], suggested the color as an economic tool for the improvement of the house and living in the city. in the same years, cézar klein designed a seaside town with full colored streets and behrens, poelzig, schmitthenner and others appealed to colorful architecture as a manifestation of joy in life. despite those calls, design only truly started perceiving color as a constructive element of the spatial box thanks to the members of de stijl, for which it get possible the balance between space and time in the pictorial composition of the threedimensional space. therefore it became one of the constructive and creative elements of the architecture: it emphasizes the plastic values, removing heavy walls. significant are the statements theo van doesburg, who stated that the building is a “monumental synthesis of space, form and color” [4]. he conceived the latter as an organic element of architectural expression, set against to its decorative and ornamental use, emphasizing the difference between the painting (the media) and the color (the goal). starting from this theoretical assumptions, the neoplasticism developed new original design concepts in which the combination of primary colors with black and white placed on the “whole” of the surfaces of the room sides shatters the unity of the spatial box. architecture applied the poetry of the abstract painter mondrian, who gave up figurative painting in order to investigate figure 2 oskar schlemmer’s design for the lobby of the workshops wing in the bauhaus in weimar (1923), isometric view. the design shows the color pattern of painted decoration in its transparency, representing the e pictorial surface, without the walls depth: ceilings and raised floors are the same, without any consistency in the projective overlap of the edges that define the surfaces walls. the color and its representation emphasize the spatial continuity on three horizontal levels that can be rebuilt, despite the image emphasizes the boundary of the box space. 58 cultura e scienza del colore color culture and science | 02/14 the concept of space. despite some important differences, the close relationship with the painting in the use of color for the renewal of architecture evokes the activity within the bauhaus, where van doesburg was a guest in weimar. 3. the laboratory of wall painting at bauhaus at the bauhaus, the awareness of color’s conditioning significance had a great relevance in its studies, which were entrusted to the teaching of painters like kandinsky, klee and itten in the preliminary courses introducing scholars to the design through practice. the experimentation of sign, shape and color were conceived as primitive elements of design: primary colors became starter elements of the process, together with the basic geometric shapes. the first manifesto of the school therefore included a workshop for decorators, stained glass designers and a wall-painting laboratory, whose first leader was oskar schlemmer’ [5]. this activity differed from the others, because of the color’s interaction with the form and the perception, even though there was no actual creation of any objects. the business was then directed towards the experimentation on the other application areas of the school, working on behalf of other sections, involving students in gropius’s direct commissions and in his private work. among these, the most successful was the contract with the firm gebrüder hannoversche tapetenfabrik rausch & co, for which between 1929 and 1930 the laboratory created two collections of oil-tapestries, selling 6,000,000 paper rolls in four years. the laboratory’s activity was well documented in the catalog of the exhibition by renate scheper, who followed the rediscovery of the bauhaus archives after the fall of the berlin wall, with the restoration of the “masters’s hauses” and the recovery of the original interior colors [6]. the work of the laboratory is interesting for two different reasons. the first one is directly connected to the experimentation of color in his formal and perceptive relationship with the spatial environment and it documents the development of bauhaus’s chromatic research in the choice of colors such as the one in representation. the initial conception of decorative finishing with expressionist taste evolves towards the abstraction of surface-defined color with deep hues showing the coexistence of two opposed concepts in the choice of color palettes: on one hand the preference for primary colors under the influence of van doesburg, on the other, the restful shades suggested by itten. the second is merely research on color representation in design, with the preference for isometric views stressing the reference to neoplasticism and finding justification in van doesburg’s visit in weimar in the late 1920s, followed by a course with 25 students in ‘22 [7]. figure 3 heinrich koch studied color combinations by the isometric opening of the room box to show colors on the covered walls. 5902/14 | cultura e scienza del colore color culture and science 4. conclusion: color research and design experimentation the research of avant-garde artists of the early ‘900 is of particular interest to the study of the controversial issue of the relationship between color and design. the contribution of the painting was extremely important in the renewal of architecture and of applied arts in general. in the crucial years of the modern movement’s birth, the activity of the laboratory of mural painting reinforced the bauhaus’s active conception of the color. the use of the color highlighted the articulation of the constructive elements of the spatial box, whose perception is determinedly conditioned by the chromatic effect. the awareness of the color’s role upgraded the conformation of the perceptual space to a qualifying element of the project, which one should define and verify carefully. this idea improved the development of the experimental approach to the representation, featured by a free reinterpretation of the conventional codes of descriptive geometry, which is expressed in an original way in axonometric projections, in the development of sides on the paper surface or in perspectives, thus involving the three alternative methods of drawing projection. the most innovative experimentation lies in the abstraction of axonometric projections, such as the joining of two different views from above figure 4 in the color design of the gallery neumann (1926) hinnerk scheper combines two opposing isometric views (from above and from below) in a unique picture, applying different graphic expedients. the white base to the left, the vertical partition dividing the space and the “transparence” of the floor / walls, conceal the merging of two different projections. figure 5 luciano baldessari, color pallet and perspective sketches for the color design of the bedroom of the spadaccini’s apartment in milan (1932) (archive casva, milan) and the pattern of color matching in the sample and in the other 10 suggested solutions. 60 cultura e scienza del colore color culture and science | 02/14 bibliography [1] p. caselli, il colore progettato. la sperimentazione cromatica ottocentesca nel progetto di damiani almeida per il teatro politeama di palermo, in disegnare, n° 2, gangemi, roma, 1991, pag. 67-74. [2] g. semper, osservazioni preliminari sull’architettura dipinta e sulla plastica presso gli antichi (1834), in architettura arte e scienza, edited by b. gravagnuolo, ciran, pagg. 87-91. [3] k. hartmann, f. bollerey, il caso taut, in rassegna (colore: divieti, decreti, dispute) edited by r. eco, n° 23, anno vii, 23/3, c.i.p.i.a, bologna, 1979, pagg. 68-74. [4] theo van doesburg, scritti di arte e architettura, edited by s. polano, officina edizioni, roma, 1979 [5] magdalena droste, bauhaus, bauhaus-archiv, berlin. [6] renate scheper, farbenfroh! die werkstatt für wandmalerei am bauhaus, bauhaus-archiv, berlin, 1989. [7] the recent exhibition dedicated to mondriand at beaubourg in paris documented through numerous drawings for internal dissolution of the continuity of spatial box through contrasting primary colors and his preference for an axonometric view of the traditional approach. [8] le corbusiers, polycromie architecturale: farbenklaviaturen von 1931 und 1959, basel, birkhauser, 2006. and from below merging in a sole image and exploiting the ambiguity of parallel perspective (as escher did some decades later in the print “concave-convex” from 1953). a common feature of the color’s project, at the beginning of the modern movement, was the attention to the representation of color combination staying faithful to the hue, which privileged the tempera or other mat paints without shadowing, even in the realistic perspectives that always have flat backgrounds. this focus reflects in the drawings of several architects. good examples are the luciano baldessari’s perspective sketches for the bedroom of the spadaccini’s apartment (1932) or figini and polini’s views for the “electrical house” with its rigorous geometric construction, and avoiding the shade of lights and shadows. even more abstract is the solution adopted by le corbusier; in 1927 he attached the real samples of color in the project documents for the maison citrohan and later on even pen-drawings illustrating the “polichromie architecturale” (1956), he indicated the combination of colors on a schematic perspective box with numbers and letters, giving up the simulation of color completely [8]. the abstraction in the representation emphasizes the “constructive” and compositional role that they gave to color, as a significant element of the design, even more important than the realistic representation of its perception. figure 6 surfaces development in the color representation of hinnerk scheper’s design for the ground floor of the building reina in dessau (1927). the three rooms have the a darker color on the windowed wall; in the middle one, which has the yellow ceiling, the backlit wall is black while the other are white like the skirtings and the frames. cultura e scienza del colore color culture and science 18 cultura e scienza del colore color culture and science | 03/15 1davide pandini davide.pandini@hotmail.it 1nicola ludwig nicola.ludwig@unimi.it 1marco gragano marco.gargano@unimi.it 2annalisa moneta 1dipartimento di fisica, università degli studi di milano 2icvbc, cnr milano metodologie per lo studio di miscele di pigmenti pittorici con spettrometria a fibra ottica 1. introduzione la tecnica della spettroscopia in riflettanza a fibre ottiche (fors) con sonda a sfera integratrice consente in modo totalmente non invasivo di ottenere spettri del fattore di riflessione spettrale (nel seguito riflettanza) nell’intervallo spettrale uv-vis-nir (200 nm 2000 nm a seconda del tipo di rivelatore impiegato) per il riconoscimento di pigmenti pittorici. nel caso di mescolanze di pigmenti, un database di riflettanze di pigmenti puri non consente un sicuro ed immediato riconoscimento dei pigmenti presenti nella miscela. in questo lavoro viene presentato un metodo per determinare con ottima approssimazione, a partire dalla misura dello spettro di riflettanza, i coefficienti di scattering s e di assorbimento k del modello di kubelka-munk per i pigmenti [13]. l’equazione di kubelka-munk viene applicata sia alla riflettanza di uno strato di spessore coprente di un pigmento puro, sia alla riflettanza di una mescolanza di pigmento con un pigmento bianco. in questo modo si ottiene un sistema di due equazioni nelle incognite k ed s risolvibile a meno di un coefficiente arbitrariamente posto pari a 1. i coefficienti k e s così ottenuti, caratteristici dei diversi pigmenti, vengono quindi raccolti in un database mediante il quale è possibile, in linea di principio, studiare il caso di mescolanze di diversi pigmenti in stesure pittoriche. le concentrazioni dei diversi pigmenti, in questo caso, non sono facilmente ottenibili se non con tecniche analitiche da laboratorio che richiedono il prelievo di un campione [4]. la ricostruzione dello spettro di riflettanza a partire dai coefficienti k ed s permette in primo luogo di prevedere a livello qualitativo i tratti caratteristici dello spettro della miscela [5]. questo procedimento si è rivelato efficace soprattutto per mescolanze binarie di un pigmento giallo con uno rosso ad ottenere una tinta arancione e per mescolanze di un pigmento blu ed uno giallo ad ottenere una tinta verde. l’ulteriore passo è la determinazione delle concentrazioni dei due pigmenti presenti nella miscela binaria a partire dallo spettro di riflettanza misurato e dai coefficienti k(λ) e s(λ) ottenuti per i singoli pigmenti. dal punto di vista sperimentale lo studio è stato condotto su 17 pigmenti tra quelli più comunemente impiegati in ambito storicoartistico nell’età moderna e contemporanea: rosso di cadmio, lacca rossa di garanza, cinabro, arancio di cromo, giallo di cadmio, giallo napoli, giallo di zinco, verde di cromo, verde oltremare, verde rame, terra verde, malachite, azzurrite, blu di cobalto, blu oltremare naturale (lapislazzuli), blu oltremare artificiale, violetto di cobalto [figura 1]. questi pigmenti sono già stati studiati con tecniche analitiche non invasive per determinarne la possibilità di riconoscimento quando si presentano, puri, in strati sovrapposti [6].figura 1 1903/15 | cultura e scienza del colore color culture and science 2. modello teorico il modello di kubelka-munk [1] considera mezzi omogenei di spessore finito h composti da particelle e assume che la radiazione interagente con ciascuna particella subisca diffusione nella stessa direzione della radiazione incidente (modello unidimensionale). a partire dalla definizione di due coefficienti fondamentali (coefficiente di diffusione o di scattering s e coefficiente di assorbimento k) il modello determina l’intensità emergente dallo strato nello stesso verso di quella incidente e quella retrodiffusa. se sotto lo spessore h dello strato è presente un fondo bianco (nel contesto della pittura è identificabile con la preparazione) tale fondo riflette indietro la radiazione fin lì giunta, che interagisce nuovamente con le particelle dello strato fino a riemergere. quando lo spessore è sufficientemente grande (hiding thickness) l’intensità diffusa nel complesso dallo strato del campione non risente delle caratteristiche del fondo, in quanto tutta la radiazione incidente è stata assorbita o retrodiffusa prima di raggiungere il fondo. in tale situazione rapporto tra intensità del fascio retrodiffuso e fascio incidente in tale condizione viene chiamata riflettanza r∞ e vale: (1.1) dalla quale è possibile ricavare il valore del rapporto k/s, ma non i singoli k e s in modo indipendente. k(λ), s(λ) e r∞(λ) sono funzione della lunghezza d’onda, ma per brevità, non è riportato nella trattazione che segue. nel caso di mescolanze di n pigmenti in concentrazioni ci note, k ed s sono ottenuti come somma pesata sulle concentrazioni di ciascun pigmento, per cui il rapporto k/s (λ) assume la forma: (1.2) per poter correlare la forma dello spettro di riflettanza con il tipi di pigmento impiegato è necessario conoscere i coefficienti di scattering ed assorbimento indipendentemente. sono già stati proposti diversi metodi per determinare queste variabili sperimentalmente, ma nel caso dell’applicazione ai pigmenti dei dipinti risultano poco appropriati per la complessità intrinseca costitutiva dello strato pittorico reale. ad esempio è possibile il calcolo di k ed s a partire dallo spettro di vernici stese con spessore ben determinato (che di certo non si confà al caso s k s k s k r 21 2 2 +−+=∞ ∑ ∑ = = ⋅ ⋅ = n i ii n i ii sc kc s k 1 1 della pittura) o mediante una serie di calcoli riferiti a sottili stesure di pigmento sovrapposte l’una all’altra [2]. viene qui proposto un semplice metodo che si basa sull’utilizzo di campioni ottenuti da mescolanze omogenee di pigmento puro con il solfato di bario usato come pigmento bianco. dalla 1.1 si ricava direttamente il rapporto k/s (che per brevità indichiamo con r p ) in funzione del valore del fattore di riflessione spettrale per ogni lunghezza d’onda: (1.3) poiché il modello di kubelka-munk porta ad avere due incognite k(λ) e s(λ), sono necessarie due equazioni linearmente indipendenti. qualsiasi misura su un pigmento steso con spessore superiore all’hiding thickness porta alla stessa descrizione matematica, e quindi allo stesso rapporto riportato nella formula 1.3. se invece si effettua una misura su una stesura di due pigmenti in mescolanza (per convenienza quello in esame con concentrazione cp ed un pigmento bianco con concentrazione necessariamente 1-c p ) vale sia la formula 1.2 che la 1.3 riferita alla mescolanza. da tale uguaglianza si ricava la seguente: (1.4) dove il pedice w indica il secondo pigmento, mentre il pedice p il pigmento in esame. una scelta opportuna di secondo pigmento è il bianco di bario, il quale è caratterizzato da un fattore di riflessione spettrale costante e prossimo al 100%. per questo pigmento è quindi ragionevole assumere un coefficiente di assorbimento k w nullo e considerare il coefficiente di scattering s w come costante in funzione della lunghezza d’onda almeno nella regione vis-nir (ossia nell’intervallo delle misure effettuate). con queste ipotesi, risolvendo il sistema contenente le formule 1.3 e 1.4 si ottengono le seguenti: (1.5) ( ) ∞ ∞−== r r s k r p p p 2 1 2 wppp wppp misc misc misc sccs kcck r r s k r )1( )1( 2 )1( 2 −+ −+ = − =      = ∞ ∞ wppp wppp misc misc misc sccs kcck r r s k r )1( )1( 2 )1( 2 −+ −+ = − =      = ∞ ∞ wppp wppp misc misc misc sccs kcck r r s k r )1( )1( 2 )1( 2 −+ −+ = − =      = ∞ ∞ w p p p p sc c rr r s ⋅ − ⋅ − = 1 )(λ w p p p p p sc c rr rr k ⋅ − ⋅ − ⋅ = 1 )(λ 20 cultura e scienza del colore color culture and science | 03/15 che consentono di ricavare i coefficienti di scattering e di assorbimento separatamente misurando r, r p e utilizzando cp note. rimane da determinare a priori il coefficiente di scattering del bianco utilizzato, che può altresì essere posto in modo arbitrario pari a 1. in figura 2 è mostrato il caso del verde di ossido di cromo, ma ovviamente questo metodo può essere applicato a qualsiasi pigmento. una volta determinati i coefficienti k(λ) e s(λ) di diversi pigmenti attraverso la 1.2 si può risalire al rapporto k/s della miscela e da questa mediante la 1.1 allo spettro di riflettanza. 3. materiali e metodi l’apparato strumentale è costituito da uno spettrofotometro (hr4000, oceanoptics®, figura 3) con sorgente a lampada alogena (con aggiunto un filtro ciano per attenuare le intensità del picco di emissione, a circa 600 nm, e migliorare quindi il rapporto segnalerumore nella zona spettrale del blu). la lampada è collegata tramite fibra ottica ad una sonda a sfera integratrice (geometria 8°/d). la radiazione raccolta dalla sonda viene condotta tramite un’altra fibra ottica allo spettrofotometro a reticolo, il quale campiona lunghezze d’onda con una risoluzione effettiva di 2,7 nm tra i 200 e i 1100 nm. per un breve periodo è stato disponibile presso il laboratorio uno spettrofotometro a reticolo e fibra ottica ma equipaggiato con un array di elementi ingaas (sensibili fino a 1700nm). le misure su questo range esteso (figura 4 e figura 5) hanno permesso per alcuni campioni di ottenere per la figura 2 verde ossido di cromo figura 3 2103/15 | cultura e scienza del colore color culture and science porzione di spettro sovrapposto (500 nm 1000 nm) un confronto interstrumentale e di valutare l’andamento delle funzioni k ed s al crescere della lunghezza d’onda [10]. il grafico del fattore di riflessione spettrale usato per la determinazione di k ed s è il risultato di una media di 10 spettri, filtrato con passo di 5 nm. per i diversi pigmenti sono state ottenute 5 diverse concentrazioni in bianco così da poter confrontare i risultati di k ed s ottenuti a partire da coppie di campioni differenti. le mescolanze sono state effettuate secondo la concentrazione in massa pigmento-bianco 1:50, 1:10, 1:5, 1:2, 1:1 oltre al pigmento puro, per 17 pigmenti: rosso di cadmio, lacca rossa di garanza, cinabro, arancio di cromo, giallo di cadmio, giallo napoli, giallo di zinco, verde di cromo, verde oltremare, verde rame, terra verde, malachite, azzurrite, blu di cobalto, lapislazzuli, blu oltremare artificiale, violetto di cobalto. le mescolanze, rese visivamente omogenee, sono state stese in olio (e diluite in trementina per facilitarne l’asciugatura uniforme) con una spatola per uno spessore superiore all’hiding thickness (figura 1). per ciascun campione sono stati misurati gli spettri in riflettanza in più punti della superficie. 4. risultati sperimentali applicando le formule 1.5 a ciascuno dei cinque spettri di miscele con il bianco associato allo spettro dello stesso pigmento puro, sono stati ottenuti cinque grafici di k ed s, che di norma si sono rivelati tra loro compatibili. in questo modo si è ottenuto lo spettro dei fattori k ed s riferiti a quello del bianco (posto pari ad 1). tali spettri hanno sempre il medesimo andamento qualitativo, ma le irregolarità di superficie del campione, le variazioni di irraggiamento della lmpada e il disallineamento sorgentefibra (che comporta una diversa intensità incidente) possono portare a degli shift lungo l’asse del fattore di riflessione spettale. poiché il riconoscimento di un pigmento avviene mediante l’identificazione dei suoi massimi e minimi di riflettanza, questo shift non pregiudica figura 4 figura 5 22 cultura e scienza del colore color culture and science | 03/15 il riconoscimento; è però difficile l’analisi quantitativa. il database di k(λ) e s(λ) così ottenuto è stato testato su mescolanze di pigmenti rossi e blu (a formare i porpora), gialli e blu (per i verdi) [8] e gialli e rossi (per le tinte arancioni). i risultati ottenuti seguono bene i profili delle misure sperimentali sui campioni di mescolanze preparati in laboratorio, ma le concentrazioni inserite del modello danno uno spettro con valori sistematicamente inferiori rispetto alla misura sperimentale. 5. applicazione a miscele binarie una volta costruito un database di valori di k ed s relativo a diversi pigmenti, è quindi possibile, in linea di principio, ricavare in modo analitico lo spettro di riflettanza di miscele di pigmenti. a titolo esemplificativo affrontiamo brevemente il caso di miscele con tinta risultante verde (mescola di pigmento blu e giallo). i pigmenti selezionati in base alla varietà dei loro spettri di riflettanza sono i seguenti: giallo di napoli, giallo di zinco, azzurrite e blu di cobalto; le concentrazioni realizzate sono state differenziate a seconda dei pigmenti coinvolti nelle mescolanze, in modo da ottenere tinte ben diversificate e non troppo simili a quelle dei pigmenti puri coinvolti nella miscela (figura 4 e figura 5). in figura 6 sono riportati gli spettri di riflettanza elaborati a partire dai valori di k ed s calcolati con il metodo descritto nel paragrafo precedente e gli spettri osservati sulle stesure coprenti, nel caso di mescolanze di blu di cobalto e giallo di napoli dalla risultante tinta verde. gli spettri di riflettanza misurati sui campioni in mescolanza ad una determinata concentrazione di pigmenti non coincidono con quelli ottenuti con la simulazione alla stessa concentrazione. correggendo opportunamente la concentrazione usata nella simulazione i due spettri raggiungono una buon livello di sovrapposizione (figura 7). si può affermare quindi che qualitativamente la simulazione a partire dal database permette di ricostruire spettro della mescolanza, ma non fornisce dati quantitativi affidabili. alcuni fattori di errore sono stati individuati: l’apparato risente notevolmente delle condizioni di superficie del figura 6 figura 7 2303/15 | cultura e scienza del colore color culture and science campioni (lucidità, regolarità, omogeneità), la presenza dell’olio nella stesura influenza la componente di radiazione riflessa nella direzione 8° di incidenza della sfera integratrice (e quindi persa dal sistema di raccolta della sfera integratrice). l’errore sulle misure quantitative potrebbe essere attribuito quindi più che ad una insufficienza del modello, ad errori sperimentali che non sono stati tenuti in conto a priori. va osservato infine che il modello utilizza concentrazioni in peso delle singole componenti laddove l’influenza sull’assorbanza ottica nella miscela è legata a concentrazioni in volume, più complesse da valutare per materiali in polvere come i pigmenti che vengono dispersi in un legante in fase di utilizzo. sotto l’aspetto qualitativo il modello descritto ha avuto invece buoni riscontri nelle osservazioni sperimentali. nell’ambito di miscele dalla tinta risultante verde è interessante notare lo spostamento verso destra del massimo di riflettanza caratteristico del pigmento blu e della spalla della banda di assorbimento dovuta al giallo verso sinistra all’aumentare della concentrazione del giallo. questo spostamento, previsto dalla simulazione, è verificato sperimentalmente. in generale la lunghezza d’onda corrispondente al massimo di riflettanza nella banda 450 nm – 550 nm consente il riconoscimento dei pigmenti blu presenti nella miscela, mentre il pigmento giallo è più difficilmente riconoscibile: in parte è identificabile dal comportamento degli spettri nel punto più alto della spalla nella banda 650 nm – 700 nm. 6. conclusioni l’identificazione dei pigmenti presenti in una stesura di una miscela binaria è, a livello qualitativo, possibile una volta che sono stati ottenuti i grafici dei coefficienti di assorbimento k e di scattering s della teoria di kubelkamunk (a meno di un fattore di scala s w ). il riconoscimento dei pigmenti avviene sulla base del confronto dello spettro misurato della miscela con alcuni spettri significativi di miscele binarie di diversi pigmenti a diverse concentrazioni, come riportato, per esempio, in figura 1. in primo luogo si delimita il campo di ricerca dei pigmenti a quelli che possono in mescolanza creare una tinta simile a quella osservata. in particolare per le miscele binarie senza bianco (impiegate in pittura dalla fine del seicento in poi) si ricorre a miscele di pigmenti blu e gialli per ottenere alcune sfumature di verde e mescolanze di rossi e gialli per sfumature arancioni, mentre più raramente blu e rossi per ottenere tinte viola-magenta (che risultano solitamente molto scure). confrontando gli spettri di mescolanze binarie ottenuti mediante il metodo descritto nel paragrafo 4 con quello osservato sul campione è possibile risalire in maniera qualitativa alla coppia di pigmenti presenti. allo stato attuale l’analisi quantitativa per valutare le concentrazioni dei due pigmenti presenti non è realizzabile con sufficiente precisione a partire dai grafici delle mescolanze ottenibili dai valori di k(λ) e s(λ) dei pigmenti. i problemi che compromettono al momento una misura quantitativa più precisa sono l’instabilità dell’apparato di misura e l’irregolarità dei campioni pittorici da confrontare con gli spettri ricostruiti attraverso i coefficienti k(λ) e s(λ). bibliografia [1] p. kubelka, f. munk: ein beitrag zur optik der farbanstriche. zeitschrift für technische physik 12 (1931), 593-601. [2] l. simonot, m. elias, e. charron – special visual effect of art glazes explained by radiative transfert equation – applied opt. vol.43, 12, 2001 – 2580-2587 [3] g. antonioli, a. della patria, f. fermi, c. oleari, s. omarini, r. poccolo, r. reverberi – proprietà della riflettanza spettrale secondo il modello kubelka-munk-saunderson – colore e colorimetria: contributi multidipliscinari vol. v. 2009 – pp. 245-253 [4] baldelli p., bonizzoni l., gambaccini m., gargano m., ludwig l., milazzo m., pasetti l., petrucci f., prino f., ramello l., scotti m. application of the k-edge x-ray technique to map pigments of art paintings: preliminary results, in: il nuovo cimento della societa` italiana di fisica. c, geophysics and space physics. issn 11241896. 29 c:6(2006). p. 663-672. [5] d. pandini – studi per la modellizzazione della riflettanza spettrale negli strati pittorici , tesi di dottorato (2012) [6] m. bertucci, l. bonizzoni, n. ludwig, m. milazzo – a new model for x-ray fluorescence autoabsorption analysis of pigment layers. in: x-ray spectrometry. issn 00498246. issn 1097-4539. 39:2 (2010), pp. 135-141. doi: 10.1002/xrs.1216 [7] p. kubelka: new contribution of the optics of intensely light-scattering materials.1948part i. josa a 38 (448457) [8] n. ludwig, m. gargano, a. galli, a. moneta – identificazione di pigmenti con spettrofotometria vis-nir:il caso dei pigmenti verdi. in ascienza e beni culturali atti v congresso aiar. morrone editore siracusa 2008 isbn 978-88-95936-11-6 [9] a. moneta, n. ludwig, g. poldi, m. gargano – cambiamenti di colore in mescolanze con bianco. uno studio su pigmenti antichi. conferenza nazionale colore e colorimetria, quaderni di ottica e fotonica, firenze, 2005 volume 13, pp.157-164 [10] m. gargano, n. ludwig, g. poldia new methodology for comparing ir reflectographic systems, infrared physics & technology, 49, 249–253, 2007. cultura e scienza del colore color culture and science 53 cultura e scienza del colore color culture and science | 08 | 2017 issn 2384-9568 lynne bartlett lynnebartlettoriginals@ btinternet.com jewellery designer/maker an overview of the history of the use of colour in jewellery abstract from ancient times rare and beautiful coloured materials have been prized and worn as adornment and/or indications of status. in early societies these materials would have been ‘found’ objects such as shells and feathers but as technologies advanced metals were used extensively. for thousands of years jewellers created beautiful objects using a range of metals with limited colours: yellow, red and white. whether the yellow was high purity gold or bronze, or the white was silver, platinum or a base metal alloy, the visual impact was essentially the same. other materials were needed to expand the palette to colours such as blue, purple and green. this paper outlines the materials and methods that were used from the earliest known examples to recent decades. historically gemstones and vitreous enamels provided jewellers with a wide range of colours. the ancient egyptians used turquoise, lapis and coral with gold to produce vibrant multi-coloured jewellery. the romans had a particular fondness for emeralds, sapphires and pearls while the anglo-saxons produced amazing jewellery featuring red garnets and blue enamel. magnificent mediaeval jewels, mostly royal status symbols, incorporated rubies, emeralds, sapphires and diamonds with fine enamels. by the eighteenth century new sources of gemstones, particularly from s america, made jewellery more affordable and subject to changes in fashion. over the ensuing decades fashionable jewellery veered from almost monochrome, diamond-set designs to multi-coloured, multi-gemstone pieces. the victorians used an amazing array of gemstones, with rare and unusual species particularly prized. the mid-twentieth century saw the introduction of metals that could be coloured such as anodised aluminium and a new metal, titanium, which enabled jewellers to produce multi-coloured pieces without the use of gemstones or enamel. keywords colour, jewellery, gemstones, titanium, aluminium citation: bartlett l. (2017) ‘an overview of the history of the use of colour in jewellery’, cultura e scienza del colore color culture and science journal, 08, pp. 53-58, doi: 10.23738/ccsj.i82017.05 received 12 january 2017; revised 6 november 2017; accepted 15 november 2017 lynne bartlett is a jewellery designer/maker. having originally studied chemistry and worked for many years in the chemical industry, jewellery is her second career. the use of colour in jewellery has been a dominant theme in her work and she currently uses titanium and dyed anodised aluminium. her doctoral thesis at the university of the arts london (2010) studied the surface of coloured titanium. 54 cultura e scienza del colore color culture and science | 08 | 2017 | 53 58 bartlett l. issn 2384-9568 doi: 10.23738/ccsj.i82017.05 1. introduction from ancient times rare and beautiful coloured materials have been prized and worn as personal adornment, indication of status and/ or for supposed protective or amuletic purposes. this paper outlines the ways in which colour has been incorporated into jewellery from the earliest times to recent decades. consideration is given to the colours of the most commonly used metals, gemstones in various forms, vitreous enamel, anodised aluminium and, finally, the interference colours of titanium. however as an overview it is not possible to include information about the cultural significance of the colours used, the sources of the gemstones or more modern coloured materials such as plastic. of all the elemental metals only two, gold (yellow) and copper (red) are intrinsically coloured. all the others such as silver, iron, nickel, etc. are white or rather various shades of grey. regardless of the workability, strength or cost, the aesthetic appearance is equivalent. whether the yellow was high purity gold or bronze, or the white was silver, platinum or a base metal alloy, the visual impact was essentially the same. gold may be manipulated by alloying to produce a range of colours namely white, yellow, red and green but the variations are subtle. vibrant colours can only be introduced by the incorporation of other materials in a piece of jewellery and it is the range and use of these coloured materials such as gemstones and enamels that are the focus of this paper. but to cover such a vast subject means that only a glimpse of the methods and materials that have been used can be provided. examples have also been limited to europe and the ancient civilisation of the middle east that have most influenced the development of european jewellery. 2. early adornment in early societies ‘found’ objects such as shells, seeds and coloured stones were used as adornment and examples have been found in graves dating back to 30,000 bc (phillips, 1996). necklaces from ancient cities in what is now iraq illustrate how the materials were fashioned and drilled so that they could be worn. in later periods found objects were augmented by beads fabricated from ceramic and glass. coloured beads with varying degrees of shaping have continued to be a significant jewellery item over the centuries. with technological advances metals began to be used extensively. gold was particularly prized for its colour, immutability and the relative ease with which it could be worked. highly sophisticated gold jewellery has been excavated from sumerian tombs dating from 2500 bc in ancient iraq. this jewellery also incorporates coloured gemstones such as lapis lazuli, garnet, turquoise and cornelian, which were fashioned into both simple and complex shapes as shown in figure 1. for example from 3000 bc turquoise beads were combined with garnets and gold. typically beads were fashioned into biconical shapes but there are also examples of more elaborate gem cutting from ur where gemstones were cut and polished to set as inlay into metal brooches (tait, 2006) the gemstones were mostly opaque and surely prized for their intense colours. the ancient egyptians used turquoise, lapis and coral to produce vibrant multi-coloured jewellery and also created beads with similar appearance from glazed composition and faience, figure 2. as glass became more available in the egyptian new kingdom (ca 1567-1085 bc) it was used to imitate natural stones as well as in fine inlay, which could be argued as the precursor to true enamel. jack ogden (ogden, 1982) gives a good overview of ancient sources of metals and gemstones and how they were worked. 3. greek and roman jewellery gold working spread around the eastern mediterranean and examples of fine gold work are known from crete, mycenae and etruria. the emphasis in this work was in the many sophisticated techniques that were used to embellish the gold surfaces. gemstones are relatively rare but examples of an early type of dark blue enamel have been found in mycenean tombs in cyprus dating from the thirteenth century bc (tait, 2006). greek jewellery, drawing on this legacy of fine workmanship, is characterised by the use of gold. only in the hellenistic period (from 325 bc) is there an increased use of coloured gemstones with fine quality cabochon cut garnets and transparent gems such as amethyst and emerald (higgins, 2006). the roman conquest of the hellenistic world and establishment of the empire (27 bc) resulted in jewellery in a similar style with the accent on gold work. but this developed into a much more polychrome style. the romans had a particular fondness for emeralds (in crystal form), sapphires and pearls as shown in figure 3. mummy portraits show how these items were worn. almost all the forms of jewellery that are worn in the twenty-first century had their origin in the roman period. romano-british jewellery reflects a merging of the ‘standard’ roman jewellery with the added influence from the strong celtic metalworking traditions. in particular colour was incorporated 55 cultura e scienza del colore color culture and science | 08 | 2017 | 53 58 an overview of the history of the use of colour in jewellery issn 2384-9568 not only from the example of roman gemstone use but also from the celtic technique of enamelling on bronze, figure 4. 4. anglo-saxon and byzantine jewellery the colour palette changed over the centuries and between different cultures. as shown in figure 5, the anglo-saxons produced amazing jewellery featuring red garnets and blue enamel (care evans, 1989). the technique of inlaying thin slices of garnet into cells of gold, backed with textured gold foils, is thought to have its origins in southern russia around 300 ad and to have spread with migration of the gothic tribes throughout western and northern europe (kidd & webster, 2006). these jewels show a great sophistication in gem cutting and gold working. in northern europe during the ninth and tenth centuries there is an increasing use of silver but in the eastern mediterranean the rise of a particular byzantine style of highly coloured jewels featured gold cloisonné enamelled work, figure 6. 5. medieval jewellery in the early thirteenth century gold was used to set polished gemstones of different colours in simple brooch forms, which also had a practical purpose. subsequently goldsmiths demonstrated their skill by creating intricate high-relief gold work which was covered in enamel and enhanced with gemstones. these highly decorative jewels were particularly figure 1 carved lapis and gold beads from ur, 2500 bc. figure 2 collar of glazed composition beads from egypt, 2020 bc. figure 3 gold bracelet with emeralds and pearls from roman egypt, 1st century ad. figure 4 copper alloy brooch with red and blue enamel faversham,uk, 1st-2nd century ad. figure 5 gold shoulder clasp with garnet inlay and blue enamel sutton hoo treasure england 7th century ad. figure 6 gold reliquary cross with cloisonne enamel constantinople, 11th century ad. all images in figs 1-7 courtesy of the british museum, london (1) (6) (3) (5) (2) (3) 56 cultura e scienza del colore color culture and science | 08 | 2017 | 53 58 bartlett l. issn 2384-9568 doi: 10.23738/ccsj.i82017.05 important as hat badges worn by men, figure 7. such magnificent mediaeval jewels were mostly royal status symbols, indications of piety or princely gifts (somers, 1980). the allegorical scenes depicted in the chased and engraved gold were embellished with rubies, emeralds, sapphires and diamonds and with fine enamels. even pendants that incorporated imitation (7) (12) (9) (11) (8) (10) figure 7 enamelled gold hat badge with rubies and diamonds spain or italy 1526-75. figure 8 enamelled gold pendant with baroque pearl, pearl drop and emerald europe late 16th century. figure 9 brooch with diamonds set in silver and hessonite garnets set in gold europe ca 1700. figure 10 base metal earrings with blue creeper bird heads england 1872. figure 11 anodised and dyed aluminium earrings jane adam ca 1995. figure 12 heat-coloured titanium neckpiece lynne bartlett 2013. all images in figs 8-10 courtesy of the v&a museum, london 57 cultura e scienza del colore color culture and science | 08 | 2017 | 53 58 an overview of the history of the use of colour in jewellery issn 2384-9568 gemstones are finely enamelled on the reverse. unusual materials and large gems were particular prized and baroque pearls (philips, 2000) were often used as the bodies of animals figure 8. in the early fourteenth century gem cutting became more elaborate and faceted stones started to be used extensively. there are examples of other styles of gem cutting such as amethyst and agate cameos. much more information from the fifteenth century onwards can be gleaned from the portraits of the period. many artists were also jewellery designers and faithfully represented the jewels worn by their sitters. in london we have a fine collection of jewellery from the late sixteenth and early seventeenth centuries in the cheapside hoard (forsyth, 2013). the hoard includes many finished pieces incorporating enamelled gold chains set with sapphires, emeralds, garnets and diamonds, carved amethysts and emerald earrings and gold rings set with rubies and other gemstones. it also contains many unset gemstones with a particularly large number of cabochon garnets. the range of materials used shows how extensive the trade in coloured gems had become and indicates the popularity of multicoloured jewellery in the period. 6. eighteenth and nineteenth century by the eighteenth century new sources of gemstones, particularly diamonds, emeralds and topazes from s america, were extensively used as in figure 9. the increased availability and hence reduced price of these gemstones made jewellery more affordable, especially for the growing affluent middle class, and designs and materials became much more subject to changes in fashion. over the ensuing decades fashionable jewellery veered from almost monochrome, diamond-set designs to multicoloured, multi-gemstone pieces and this cycling of styles has continued through the twentieth century. the victorians used an amazing array of gemstones, enamels and other materials, with rare and unusual species particularly prized figure 10. in the late nineteenth century new metals such as platinum and aluminium were increasingly used but both were essentially white metals. the strength of platinum made it an ideal material for ‘invisible’ settings in which the gemstones played the major role in the design of the piece. initially the whiteness of the metal and its relative lack of tarnish meant that it was used as a setting for diamonds replacing the mixed gold and silver settings of early diamond-set jewels but designers at the prestige fine jewellery houses such as cartier increasingly used multi coloured gemstones. aluminium, when it was first produced in the mid-nineteenth century, was treated as a novel material set in gold mounts. the isolation of the pure metal was very difficult and small ingots of the purified metal were shown at the paris exposition in 1855. it is perhaps not surprising that the modernising nephew of napoleon bonaparte, napoleon iii, ordered the fabrication of aluminium utensils and is reported to have eaten from an aluminium plate in preference to a gold one (venetski, 1969). other special uses for aluminium included the cap on the top of the washington monument which was cast from aluminium in 1884 because of its whiteness and resistance to tarnish (dix, 1934). the statue of eros at piccadilly circus was cast in aluminium in 1893. as new processes for aluminium production were developed, the metal became readily available and was used for general construction and the growing aeronautical industry in the twentieth century. 7. twentieth century metals that could be coloured were introduced in the twentieth century. in 1923 anodising of aluminium was developed to provide protection from corrosion of seaplane parts. the process thickened the natural aluminium oxide layer on the surface to provide a durable hard layer. when first created the thin porous oxide layer on the surface of the metal is very receptive to dyes and a wide range of patterning techniques can be used to produce what is effectively a coloured metal surface. dyed anodised aluminium jewellery was probably first produced in the usa but of particular note is the work of the uk jeweller, jane adam an example of which is shown in figure 11. colours may be bright or subtle and, as the pigments are fixed in the thin adherent oxide layer on the surface of the metal, they are very durable. the lightweight of aluminium and the broad range of decorative possibilities have made it a significant material for the twentieth century jeweller. an area of colour that has not been covered so far is patination. examples exist from antiquity of metal sculptures that have been coloured in this way and historic armour used ‘bluing’ to provide multicoloured surface decoration (tellez, 2011). however, as much historic jewellery has been buried, it is often not possible, even if the underlying metal has survived, to be sure if the whole surface was coloured. the twentieth century saw the introduction of a new metal, titanium, whose colour could be said to be produced by a form of patination, i.e. 58 cultura e scienza del colore color culture and science | 08 | 2017 | 53 58 bartlett l. issn 2384-9568 doi: 10.23738/ccsj.i82017.05 oxidation. industry values titanium for its unique combination of high strength and low weight, and although this has been exploited by a few designer/makers, it is titanium’s colour potential that most attracted jewellers to the material and led to its expanding usage through the 1970s and 1980s. the thin oxide layer produced on the surface of the metal by heat or anodising resulted in a wide range of interference colours. various ways of preventing oxygen reaching the surface by masking were used to produce stunning optical effects. research has established (bartlett, 2009) that the use of titanium for designed jewellery was a technical innovation, pioneered in the uk and instigated by the titanium metal producers. early users of titanium tended to use coloured pieces in a similar way to gemstones by setting them in silver frames or fixing them with silver pins. however the strength of titanium meant that very thin sections could be cut as integral pins. its biocompatibility also meant that integral ear wires could be produced without the problems that have been associated with the use of nonprecious metals for such a purpose. one of the pioneer jewellers who first used titanium at birmingham (1965-1968) was ann marie shillito. the first identifiable piece of designed titanium jewellery is a belt buckle. another artist of note in the early decorative use of titanium was pietro pedeferri, a university researcher in electrochemistry in milan, he was inspired by the colour possibilities of the metal to produce wonderful compositions on titanium. in this case he used flat sheets of titanium as a canvas. by the early 1970s titanium had become a regular product used in jewellery courses. however its popularity peaked in the late 1980s and it is only in recent years that its use has been revived, figure 12. 8. conclusion this rapid survey has provided an outline of various materials and methods that have been used to incorporate colour into jewellery over many centuries. jewellers have been shown to readily incorporate new materials and exploit new sources of valued gemstones as they become available while building on the legacy from previous periods. precious metals and gemstones continue to provide the most desired raw materials for the manufacture of jewellery but whatever the material, colour continues to be a major factor in jewellery design and new coloured materials are eagerly adopted. funding this research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. conflict of interest the authors declare that there is no conflict of interest. bibliography bartlett, l, (2009) ‘variability in coloured titanium surfaces for jewellery’, phd thesis, central saint martin’s college of art and design, university of the arts london, london. care evans, a. (1989) ‘the sutton hoo ship burial’, british museum publications, london. dix, jr. e.h. (1934) ‘aluminum cap piece on washington monument’ metal progress (cleveland, oh: american society for metals, december). forsyth, h., (2013) ‘london’s lost jewels’, philips wilson publishers, london. higgins, r. (2006) ‘the greek and roman world, 7000 years of jewellery’, british museum press, london, p.84. kidd, d, & webster, l, (2006) ‘7000 years of jewellery’, british museum press, london, p.101. ogden, j. (1982) ‘jewellery of the ancient world’,trefoil books ltd., london. phillips, c (1996). ‘jewelry from antiquity to the present’, thames and hudson ltd., london, philips, c. (2000) ‘jewels and jewellery’, v&a publications, london. somers cocks, a g, (1980) ‘princely magnificence court jewels of the renaissance, 1500-1630’, debrett’s peerage ltd., london. tellez, h et al (2011), ‘multi-analytical study of patination methods on steel substrates: a full insight into surface chemistry and morphology’, anal bioanal chem, doi 10, 1007/s00216-011-5473-6, oct. 2011. tait, h. (2006) ed. ‘7000 years of jewellery’, british museum press, london. venetski, s. (1969). “”silver” from clay”. metallurgist. 13 (7): 451–453. (7) cultura e scienza del colore color culture and science 04 15 riv is ta s em es tr al e | h al fye ar ly jo ur na l rivista dell’associazione italiana colore www.gruppodelcolore.it cultura e scienza del colore color culture and science http://www.gruppodelcolore.it cultura e scienza del colore color culture and science rivista dell’associazione italiana colore http://jcolore.gruppodelcolore.it/ issn 2384-9568 direttore responsabile | editor-in-chief maurizio rossi vicedirettore | deputy editor davide gadia comitato scientifico | scientific committee john barbur (city university london, uk) berit bergstrom (ncs colour ab, se) giulio bertagna (b&b colordesign, it) janet best (natific, uk) aldo bottoli (b&b colordesign, it) patrick callet (école centrale paris, fr) jean-luc capron (université catholique de louvain, be) osvaldo da pos (università degli studi di padova, it) bepi de mario (crasmi, it) hélène declermont-gallernade (chanel parfum beauté, fr) reiner eschbach (xerox, usa) alessandro farini (ino-cnr, it) christine fernandez-maloigne (university of poitiers, fr) renato figini (konica-minolta, eu) davide gadia (università degli studi di milano, it) robert hirschler (serviço nacional de aprendizagem industrial, br) sandra krasovec (fashion institute of technology, usa) francisco imai (canon, usa) lia luzzatto (color and colors, it) kevin mansfield (ucl, uk) veronica marchiafava (ifac-cnr, it) gabriel marcu (apple, usa) manuel melgosa (universidad de granada, es) anna grazia mignani (ifac-cnr, it) annie mollard-desfour (cnrs, fr) maria luisa musso (universidad de buenos aires, ra) claudio oleari (università degli studi di parma, it) laurence pauliac (historienne de l’art et de l’architecture, paris, fr) marcello picollo (ifac-cnr, it) renata pompas (afol milano-moda, it) boris pretzel (victoria & albert museum, uk) noel richard (university of poitiers, fr) katia ripamonti (cambridge research system, uk) alessandro rizzi (università degli studi di milano, it) maurizio rossi (politecnico di milano, it) jodi l. sandford (università di perugia, it) raimondo schettini (università degli studi di milano bicocca, it) gabriele simone (st microelectronics, it) andrea siniscalco (politecnico di milano, it) ferenc szabó (university of pannonia, hu) mari uusküla (tallinn university, ee) francesca valan (studio valan, it) ralf weber (technische universität dresden, de) alexander wilkie (charles university in prague, cz) collaboratori | contributors walter arrighetti, simone bianco, rossella catanese, gloria menegaz, emanuela orlando, giulia paggetti, renata pompas, jodi l. sandford, raimondo schettini, jada schumacher, arvi tavast, mari uusküla, veronica valdegamberi, paola valentini redazione | editorial staff aldo bottoli, daria casciani, davide gadia, veronica marchiafava, francesca valan editore | publisher gruppo del colore – associazione italiana colore www.gruppodelcolore.it 04numero 04 ottobre 2015 number 04 october 2015 gruppo del colore associazione italiana colore cultura e scienza del colore color culture and science rivista dell’associazione italiana colore registrazione presso il tribunale di milano al n. 233 del 24.06.2014 http://www.gruppodelcolore.it sommario | summary english recensioni 04 4 8 14 22 31 36 43 49 56 60 repainting the mechanical ballet. restoration of colours in ‘ballet mécanique’ by fernand léger by rossella catanese on the perceptual/linguistic origin of the twelfth basic color term in the italian color lexicon by veronica valdegamberi, giulia paggetti, gloria menegaz motion picture colour science and film ‘look’: the maths behind aces 1.0 and colour grading by walter arrighetti a cognitive linguistic usage perspective: what is italian blu, azzurro, celeste? do english agree on blue semantics? by jodi l. sandford society in colour: italian television and the switch to colours by paola valentini color, mon dieu: a case-study comparison between the church of the epiphany (new york city) and kresge chapel (cambridge, massachusetts) by jada schumacher how blue is azzurro? representing probabilistic equivalency of colour terms in a dictionary by arvi tavast, mari uusküla adaptive illuminant estimation and correction for digital photography by simone bianco, raimondo schettini i colori di gualtiero marchesi | gualtiero marchesi’s colours by emanuela orlando jean-gabriel causse, lo stupefacente potere dei colori, ponte alle grazie, milano, 2015 a cura di renata pompas rubrica | column cultura e scienza del colore color culture and science 40 cultura e scienza del colore color culture and science | 01/14 daria casciani daria.casciani@polimi.it maurizio rossi maurizio.rossi@polimi.it design department politecnico di milano coloured lighting, urban underground and human beings: relationship inquiry through showcase analysis 1. methodology the methodology of this study is based on a multi-disciplinary bibliographic review in the fields of colour, light, perception, environmental psychology. the aim is to understand the relationship between human beings and built underground public interiors under certain lighting conditions. the paper is organized in a prior part concerning the literature review and a secondary part of showcases’ analysis using three main factors: • coloured lighting (cl): the natural/ artificial, the cool/warm cct, the brightness/intensity, the distribution of light in a balance of variety and contrast and a balance of unity and complexity, the chromatic complementary selection, the symbolic/artistic value, the way-finding value, the dynamics, the enhancement of architecture. • urban underground (uu): the environment, the spaciousness, the enhanced architecture and materials, the identity, the animation. • human beings (hb): evaluative impressions such as pleasant, interesting, comfortable, safe; opposite feeling such as arousing-calming. 2. interaction between human beings, environment, light the focal point of this paper is the investigation of the reciprocal relationship of cl + uu + hb with the aim to understand what kind of lighting attributes are preferred and what kind of lighting scenarios can define a more comfortable, interesting or safe environment. 2.1 uu + hb in the big urban areas, the necessity of new infrastructures to support mobility flows of people is an emergent and spread phenomena. the evolution of the city is based on connective networks into urban anonymous locations, enormous underground pathways, dark galleries into the bowels of the earth and connective corridors that host nearly millions of passengers each day for a short period of transit. constantly lit by artificial lighting, the underground spaces are often perceived negatively because their features are too unnatural and poorly designed: these places shows a lack of identity, because they are not characterized by the people that inhabit them, they are not relational because they do not create reciprocal relationship between users and they do not represent historical or cultural references. according to marc augè, these “non-places” are built for a stereotype user abstract the contemporary city appears as a chaotic entity, in continuous evolution and growth, with an increasing request of fast connections: for this reason a high number of design efforts are dedicated to support mobility flows on long/medium distances, favouring the use of underground spaces. these new infrastructures are perfect and efficient public interiors, conceived as “machine spaces” and designed ergonomically for a stereotype traveller [1]. as an opposite trends, several undergrounds were designed taking into account the qualitative perception of the space: they are completely transformed in containers of high-quality experiences for positive waiting periods especially through coloured and varied lighting. quantity, intensity and distribution of light and also the dynamics of both the chromatic colour temperature (cct) of white light and the hue of the coloured lighting can create a more interesting and comfortable environment. this paper analyses the impact of coloured lighting on the perception of the users through a showcase analysis and describes the relationship with human beings and environment in order to prefigure new possible insights for high quality public indoor urban environments. 4101/14 | cultura e scienza del colore color culture and science in order to create efficient structures based on standards and ergonomics parameters: everything is calculated for the maximum result in terms of decibel, lux, length of pathways, typologies and quantity of information given [1]. 2.2 hb + uu the underground stations are exchange zones of individuals, “terrain vague” made of casual social meeting and rigid behaviours because they are strictly regulated by few but mandatory rules. despite of the fact that the passenger of the subway is thought as a common subject or just a client of a service, in the book “un ethnologue dans le metro”, marc augè focus on some behaviours of the travellers of the subway in a very iconic way. he describes the repeated social rites that take place, day by day, in the urban playground of the underground stations: the activity is recurrent, regular and without surprises to the observers, every transit is repeated equally each day. the ritual and social paradox of the subway is that all individuals are alone in their activity but in the meanwhile they live a social and collective situation: they are a crowd without participating to any feast but they are also alone without being isolated [2]. the users of the subway deal with time and space adapting himself to the situation and being somehow obliged by a chronic hurry, moving quickly in the corridors and on the stairs. this particular places of interchange are very meaningful because they symbolize the space where people pass from an activity to another, performing instrumental behaviours, moving simply from one place to another but generally transforming their social rules. 2.3 cl + hb light is an indispensable environmental input for human beings, with physiological and psychological effects [3]. primary importance of light for human beings is vision in order to see, understand and use the space, orient by perceiving physical surroundings, limits and details. more than vision, light has psychological effects on human beings because it can foster a sense of safety and security, contributing to the comfort perceived. in addition to this, the quantity and colour of light arouses definite emotional reactions and aesthetic preferences somehow related to our emotional and instinctive senses [4]. more in general, the information of the perceived urban environment is codified by the human visual system that interprets certain regularities in the luminous phenomena in relation to three characteristics of light: intensity, wavelength and distribution in space. the intensity refers to the perceived luminance (brightness) of objects and surfaces: it is a subjective factor because it is an interpretation modified by psychological factors. the wavelength enables the understanding of colours and is related to the relationship between the light spectrum emitted and the light spectrum reflected by the objects and surfaces in the space. the distribution of light contributes to the making sense (legibility, coherence, complexity and mystery) [5] of the urban environments: it dynamically shapes the environment itself, showing or hiding certain information, dimensioning its volume, guiding the eyes in understanding it, suggesting its atmosphere. 2.3.1 cl + hb: perception of light and its effects the majority of the studies that aimed to systematize the relationship between perceived attributes of lighting and emotional reactions revealed that people use brightness and distribution of lighting as a basis for their judgments about interior spaces. moyer stresses that light has the capability to create shape and emotional responses through the use of compositions and organization of lighting elements [6]. the research of flynn connects lighting conditions to users’ mood: non-uniform lighting generates relaxation and bright and uniformly lit interiors boost the feeling of spaciousness [7]. more than this, his researches pointed out that relaxation is related to non-uniform wall lighting, perceptual clarity to higher horizontal lighting in a central location, spaciousness to uniform lighting and bright walls [8]. the bartlett group’s studies concluded that people generally prefer brightly lit interiors and, according to moyer, they are attracted by brightly lit objects more than by softly lit objects. on the other hand too high contrast lighting scenes creates confusion and it is necessary a lower lighting between the different spots to form visual bridges in the view. the review of literature reveals also that lighting composition and direction can be useful for safety and security perception, reducing the fear of crime by increasing the visibility, decreasing the opportunities for criminal acts and also strengthening the community confidence, cohesion and social control [9]. 2.3.2 cl + hb: perception of colours and its effects literature reveals that most people have similar emotional reactions to different colours: this is explained by several psychologists as the result of cultural learning. on the other hand, cross-cultural studies concluded that emotional reactions of people to colours are more innate than learned. heinrich frieling [10] presented the findings of a study on the psychological effects of coloured light on human beings. the subjects of this study were asked to look into red, yellow, 42 cultura e scienza del colore color culture and science | 01/14 green, and blue light. this study revealed that red is a stimulating colour, yellow is a tensing colour but releasing at the same time, violet-blue increases the inner reactivation, concentration and calmness and green stimulates similar emotions as a balanced and diffused light. studies have also shown that human beings require a balance of unity and complexity in the built-environment because the natural conditions humans beings are used to are with changing variables while the unnatural conditions are the static or too chaotic ones. faber birren [11] stresses that people expect all senses to be moderately stimulated at all times in the built-environment: the lack of complexity is generally not preferred and results in adverse psychological reactions. conversely, human beings tend to get easily confused when they are subjected to different, incoherent visual stimuli. for this reason, a balanced constantly changing environment can determine normal consciousness and positive, aroused perception. in lighting design, mahnke [12] stresses that in the total environment there should be colours in changing degrees of lightness (light and dark), cct (warm and cool), and intensity (strong and weak), providing a good balance of variety and unity: variety is necessary for attraction and interest; unity is essential for a favourable impression. 3. international case studies of underground urban interiors the selected and analysed showcases listed below are some of the best practises useful to understand how light and colours can create comfortable and high quality environments. 3.1 berlin, potsdamer platz station since the summer of 2000 the potsdamer platz in berlin has built three heliobus light pipes, respectively 14 metres, 17 metres and 21 metres high. they are the key element of the architectural design for the remodelled square because of their iconic structure but also for their sustainable function. they connect the surface level architecture and the underground station below providing the necessary light during the day: the aesthetics of the light pipe is achieved by the use of heliobus technology, using direct sunlight as the prominent source and reflecting the rays inside a lined glass tube covered internally by a high reflective material [13]. the sustainability of the lighting project is insured by the high levels of transferred light from outdoor to interior spaces using almost no energy during the day. moreover natural light provides very changeable effects in intensity (light and darkness) and cct variations according to solar incidence at different daytimes. 3.2 munich, westfriedhof subway station the forty years old subway station “westfriedhof” (opened in 1971), located at the border of the districts “neuhausen-nymphenburg” and “moosach” in munich, was re-designed in 1998 by the cooperation of the architecture office auer-weber and the municipal underground department. moreover the mvg commissioned the lighting designer ingo maurer with illuminating the platforms of the underground station [14]. he conceived a strong lighting design atmosphere, creating a place that conveys pleasant and comfortable feelings. above the platform they installed eleven oversized concave aluminium luminaries, each measuring 3.80m in diameter with differently lacquered interiors, bathing the station in blue, red and yellow light and dividing the platform into different colour shadings. the walls and the ceiling are drenched in blue light and lend the station, that is completely realized in concrete, the character of a cave, whereas the platform itself is rather bright. despite the spotlights there are no dark corners. the lighting project elevates the platform to a stage and immerses it in a warm light: rather than feeling exposed, the waiting passengers feel a sense of protection. 3.3 munich, freiheit station another interesting lighting work realized by ingo maurer is the freiheit station of munich. the aim was to lend the station a fresh, cheerful character, modernizing it with a distinctive look through both lighting and coloured surface design of ceiling, walls and floor. the lighting designer installed 3200 mirror elements on the roof using 204 square caissons and creating a sense of great openness reflecting and doubling the space. two complementary colours dominate the scene creating an interesting chromatic scenario with a provoking and entertaining vivid atmosphere. a luminous yellow shines from the large walls behind the tracks; the pillars, which are covered with blue tiles, are lit by an appropriate leds lighting that also intensifies their colour. the remaining walls and floor are covered by a unique silvery-grey material. moreover square cases for the light sources are arranged irregularly on the ceiling, adding a dynamic aspect to the platform [15]. 3.4 oklahoma, light gallery underground designed in 2007 by the office elliott + associates architects, this underground series of passages located in oklahoma city and known as “la conncourse” use coloured light to orient, give information and identify specific functions of each corridor. the coloured lighting has a functional meaning, useful to enhance the 4301/14 | cultura e scienza del colore color culture and science figure 1 berlin, potsdamer platz station, heliobus light pipe figure 2 munich, westfriedhof subway station, auer-weber figure 3 munich, freiheit station figure 4 oklahoma city, light gallery underground figure 5 oslo, nydalen station 44 cultura e scienza del colore color culture and science | 01/14 perception of the public space and to identify specific zones of the city. it is used to lit the space in a very iconic way but also to communicate with the passers-by, signalling the direction and creating an emotional atmosphere dipped into colours. the lighting sources are coloured fluorescent t8 tubes: blue lighting conduces to institutions, red lighting to hotels and green lighting is used for connective corridors. more than this, the longest gallery is a permanent installation of light. the walls are made of pierced steel, the floor is yellow and the ceiling is backlit with a blue coloured light: when the two colours merge, a white light is created on the opposite wall of the gallery [16]. 3.5 oslo, nydalen station the “tunnel of light” is a work of art performed in august 2003: light, music, technology and architecture are shaped together as an integral synesthetic whole and they also dynamically interacts with the users of the escalator of the nydalen station thanks to several sensors integrated in the space. the concept is about guiding the travellers during their daily route into an half a minute experience of dynamic sounds and lights that together perform different seasons. the architect kristin jarmund initiated the “tunnel of light” project cooperating with a group of artists to develop the multimedia concept: the technical light and sound installation is integrated in a 27 metres long translucent glass tunnel wrapped around the station escalator [17]. lighting and sound installation comprises 800 individually controlled pairs of cold cathode light tubes and 44 individually controlled loudspeakers. 4. conclusions to summarize, the schemes show the relationship of cl+uu+hb: specific characteristics of light and colours occur in the specific environment of urban underground with specific effects and impacts on the perception of the space by the users. bibliography [1] m. augè, “non-lieux, introduction à une anthropologie de la surmodernité”, le seuil, 1992. [2] m. augè, “un ethnologue dans le métro”, hachette, 2001 [3] f. birren, “light, color, and environment”, new york, van nostrand reinhold co, 1969. [4] p. zumthor, “atmosfera”, 1st edn barcelona; editorial gustavo dili, 2006. [5] r. kaplan & s. kaplan, s. the experience of nature: a psychological perspective. cambridge university press, cambridge, 1989 [6] j. l. moyer, “the landscape lighting book”, john willey & sons, inc. new york, 1992 [7] j. e. flynn, c. hendrick, t. spencer, & o. martyniuk, “a guide to methodology procedures for measuring subjective impressions in lighting”, journal of the illuminating engineering society, 8, 1992, pages 95-110 [8] j.a. veitch, & g. r. newsham, “determinants of lighting quality i: state of the science.” journal of the illuminating engineering society, 27, 1998, pages 92-106. [9] s. atkins, s. husain, and a. storey, “the influence of street lighting on crime and fear of crime”, (crime prevention unit paper 28), london: home office, 1991. [10] h. frieling, “gesetz der farbe (the law of color)”. gottingen: musterschmidt verlag 1990. [11] f. birren, “physiological implication of colour and illumination” in the psychology of colour and illumination, may 1969. retrieved the 23/06/2013 http://www.ies.org/ pdf/100papers/018.pdf [12] f. h. mahnke, “color, environment, and human response: an interdisciplinary understanding of color and its use as a beneficial element in the design of the architectural environment”, john wiley and sons birren, 1996. [13] heliobus, www.heliobus.com/en/products/lightpipe/ applications/object1/, retrieved the 14/05/2014 [14] westfriedhof subway station, http://www.mvvmuenchen.de/static_netzplan/freizeit/images/mvgmini_u-bahnhoefe.pdf, retrieved the 14/05/2014 [15] munich, freiheit station, http://www.ingo-maurer. com/en/projects/muenchner-freiheit, retrieved the 14/05/2014 [16] oklahoma city, light gallery underground, http:// www.e-a-a.com/portfolios/underground, retrieved the 14/05/2014 [17] oslo, nydalen station, http://www.kjark.no/nydalen_ metro_station_oslo_norway, retrieved the 14/05/2014 cultura e scienza del colore color culture and science 2101/14 | cultura e scienza del colore color culture and science 2. il colore negli ambienti, per star bene con se stessi e migliorare i rapporti con gli altri l’importanza dei colori usati nell’arredamento e l’influenza che hanno su noi esseri umani diventa particolarmente chiara se pensate che trascorriamo, in media, due terzi della nostra esistenza al chiuso. il colore è uno degli elementi fondamentali che determinano comportamenti e stati d’animo, relazionati con l’ambiente che ci circonda. esso può trasformare un locale spento e ordinario in un luogo che ci ravviva e ci carica di energia. addirittura, cambiare il colore delle pareti può avere un effetto superiore rispetto al cambiamento della disposizione dei mobili, ed è, fra l’altro, molto più facile da mettere in pratica. nella scelta cromatica degli ambienti della casa dobbiamo riuscire a slegarci da ciò che impedisce alle persone di “giocare” con i colori, un modo di avventurarsi alla scoperta di se stessi. per questo è necessario, comunque, conoscere poche regole vestite da consigli tecnici che non limiteranno la nostra creatività, ma aiuteranno a vivere con più armonia la nostra abitazione. gli ambienti diventeranno alleati della salute e del benessere, aiutandoci a ritrovare un equilibrio psico fisico spesso dimenticato. per ottenere il massimo beneficio dai colori che ci circondano, dobbiamo scoprire qualcosa di più sui nostri rapporti personali con i colori stessi, in modo da capire meglio eventuali simpatie ed antipatie in merito. un primo test è quello di porre più attenzione ai colori all’interno di una azienda turistica, prendendo in considerazione gli oggetti di cui vi circondate nella vita di tutti i giorni. iniziate ad essere più consapevoli dei colori che più spesso vi stanno intorno, riconoscendone la “gamma”. quante volte vi siete coscientemente fermati a chiedervi per quale motivo avete scelto un determinato colore? il colore della tinteggiatura, della carta da parati, delle stoffe e di tutti gli altri materiali che trovate nella stanza sono il modo di vestire l’alloggio proprio come gli abiti indossati sono gli ornamenti che rivestono la pelle. per non compiere scelte errate occorre essere consapevoli della stanza in oggetto e concentrarsi sul colore che si sta usando. questi due punti di vista tendono a sovrapporsi: sforzatevi di tenerli ben separati all’interno della vostra mente. le sfumature tenui, il bianco 1. effetti cromatici come supporto al turismo, al benessere e al tempo libero l’obiettivo prioritario del progetto è quello di far comprendere le caratteristiche del fenomeno turistico, con l’ausilio di conoscenze sulla comunicazione del colore, e le sue dinamiche strutturali ed i processi di trasformazione che sono in atto. il turismo è infatti, un fenomeno sociale complesso, caratteristico delle società moderne, che va approfondito da un punto di vista sociologico, sia teorico che empirico, e non semplicemente secondo la prospettiva economicistica o aziendalista. in quest’ottica la presente ricerca avrà una duplice prospettiva. in primo luogo il tentativo di dar conto delle principali teorie ed interpretazioni sociologiche del fenomeno turistico legato al colore. in secondo luogo far conoscere i metodi di analisi e le principali ricerche empiriche. il colore è uno dei fattori principali che determinano il modo in cui ci poniamo nei confronti dell’ambiente che ci circonda. viene spesso sottovalutato questo aspetto che ci avvolge con discrezione ma non senza conseguenza per il nostro umore. “l’ambiente è il mezzo esistenziale completo dell’uomo e comprende la natura fisica in tutte le sue dimensioni, la società, le istituzioni, e la molteplicità di manufatti che l’uomo ha creato mediante le tecnologie”. (h. ozbekhan) prendere conoscenza con l’ambiente significa creare un rapporto comunicativo con il mondo delle immagini che ci circondano, impegnarci nel comprendere il linguaggio degli uomini in quanto individui e società. tra oggetto e soggetto si instaura una stazione ricetrasmittente di veri e propri messaggi che giungono al soggetto, secondo quanto indicato nella psicologia della forma e del colore. si rende evidente che la comunicazione diviene un processo intenzionale e non causale. l’uomo d’oggi vivendo nei quartieri sempre più affollati e oltre il limite massimo di popolamento, viene sempre più sollecitato dalla tensione emotiva e dall’affaticamento psicologico fino all’usura dell’organismo. bepi de mario bepidemario@gmail.comcolore e turismo sociologia dell’ospitalità turistica 22 cultura e scienza del colore color culture and science | 01/14 e i colori pastello sono adatti per ogni stanza, evitando comunque la monocromia assoluta. nell’ingresso è bene non ricorrere a colori scuri che possono dare una sensazione negativa. nella zona di soggiorno è meglio scegliere una base tenue, le accentuazioni di colore (per mobili e complementi d’arredo) possono essere anche molto calde, nelle sfumature del rosso e dell’arancio, purché non troppo aggressive. in cucina sono indicati il giallo e il bianco, che mettono in evidenza l’igiene del locale e contribuiscono a percepire correttamente i colori naturali dei cibi. nelle camere da letto, pareti e soffitto azzurri risultano sempre rilassanti; anche il blu, magari con un tocco di viola, può essere utile per chi soffre di insonnia. per lo stesso motivo sono da evitare il giallo e il rosso, che sono colori eccitanti. le camere per i bambini dovrebbero colorarsi di tinte vivaci, accostate armonicamente fra di loro: giallo, arancio, verde e rosa. evitare il rosso che può causare disturbi del sonno. nelle camere per lo studio vanno impiegati toni come il bianco e il giallo, che risvegliano la concentrazione e la fantasia, ma per gli ansiosi e gli irritabili sono meglio l’azzurro e il verde. nel bagno, il bianco dà una sensazione di pulizia, il verde e l’azzurro richiamano le tonalità dell’acqua e sono rilassanti. da evitare il grigio scuro e il marrone, associabili a sensazioni di sporco, e anche il rosso che richiama il colore del sangue. nei corridoi meglio evitare i colori scuri e prediligere tonalità chiare e pastello. 3. colore spazio ambiente “per motivi religiosi o politici o più semplicemente per esprimere sentimenti ed emozioni, da sempre ed in ogni luogo l’uomo ha inseguito un ideale: creare la bellezza e possederne il mistero”. 3.1 alcune riflessioni sull’esperienza “colore” è un’esperienza che abbiamo fatto tutti quella del buio, trovarsi immersi nel buio, non vedere altro che nero. dopo il tramonto del sole ogni cosa perde gradatamente forma e colore. basta un raggio di luce che filtra dalla finestra, ed ecco che dal buio emergono le sagome, le forme, i colori degli oggetti, delle persone, delle piante, degli animali. nel linguaggio corrente si parla di “luce della conoscenza” e si dice “sei luce dei miei occhi” per sottolineare l’enorme importanza di una persona. luce – occhi: non solo un fenomeno fisiologico, ma un’esperienza che coinvolge profondi significati. il colore rispetto alla forma è codificato ad un livello più basso del sistema nervoso ed è, quindi in questo senso, più arcaico. wittengstein ci fa notare che se ci chiedessero “che cosa significano le parole rosso, blu, nero, bianco?”, potremmo indicare subito certe cose che hanno quel colore, e non di più. il colore secondo gregory (1991) – non è in relazione soltanto con la lunghezza d’onda, ma dipende anche dal significato che acquista quando sta a rappresentare un oggetto. già la concezione spaziale razionalistica di le corbusier, dice “...che le case fossero tutte bianche per legge, una simile pulizia fa vedere gli oggetti nella loro verità assoluta…”. scriveva kandisky nel suo volume “lo spirituale dell’arte” (1912), che “…il bianco è il simbolo di un mondo in cui tutti i colori sono spariti e che esso agisce sulla nostra psiche freddamente creando un silenzio assoluto …”. una delle ricette vincenti per “trasformare” lo spazio nei luoghi turistici come alberghi, villaggi o masserie agrituristiche, è di accostare, là dove manca, la luce, toni caldi e freddi (rosso, giallo ed azzurro), per creare un violento contrasto percettivo che distolga psicologicamente l’attenzione dal senso fisico e reale dello spazio, dove invece esiste forte luminosità; i materiali quali cemento e legno rimangono naturali, dialogando unitamente con tinte azzurre fredde nell’intento di dilatare lo spazio. l’uso dei colori naturali o artificiali, la loro stesura uniforme, o a strisce, sono scelte dipendenti dall’esigenza di evidenziare o meno rapporti e ritmi spaziali. risulta quindi necessario saper scegliere nei vari ambienti e secondo le funzioni e l’impiantistica destinate, i “materiali di rivestimento” per dimensioni, toni e caratteristiche (carta, tinteggiatura, tessuti) cercando di evitare, con l’allestimento dei mobili, una confusione cromatica e non trascurando nello stesso tempo gli effetti della luce naturale delle aperture finestrate, oltre che della luce artificiale che si è progettata per dar forza a certe funzioni ritenute principali. l’uso dei colori primari risulterà quindi più stimolante ed allegro negli ambienti soleggiati, nei soggiorni, negli ambienti di sosta e d’incontro, alternandoli però con colori neutri; mentre per ambienti quali ospedali o luoghi di riposo si useranno colori rilassanti e neutri ravvivati da suppellettili colorate a toni diversi. così nelle vecchie ed anche nelle 2301/14 | cultura e scienza del colore color culture and science nuove fabbriche si interviene con il colore per riscattare un ambiente degradato, con il risultato notevole sia per l’uso del luogo e sia per l’attività produttiva sicuramente in aumento e con riduzioni di incidenti. gli stessi aeroporti “vestiti” con sfumature blande, con sottofondo musicale e comode poltrone, tendono a calmare il passeggero in attesa, oltre a sottolineare con colori vivaci le porte d’imbarco. idee di colore, queste, estremamente variabili per la luce naturale a seconda della latitudine, delle stagioni e delle ore del giorno, e che risultano incomplete per la luce artificiale in quanto, mancando di alcune lunghezze d’onda, non presentano in modo corretto l’intera gamma dei colori. sui colori sono state elaborate varie teorie nel corso della storia; mi preme citare platone che ci ricorda che il gioco dei colori ha un aspetto divino. gli organi di senso ci sono stati donati per raggiungere un’unità armonica con il mondo, e l’organo della vista è la creazione più preziosa ed artistica. in altre parole la decorazione sta assumendo un suo carattere semantico originale e di trasformazione linguistica, una sua identità culturale e sociale, attraverso segni astratti, simboli e significati, capaci di “condizionare e determinare” l’uso visivo del prodotto. 4. colore come strumento di comunicazione da questo punto incominciamo ad analizzare cosa può essere considerato “relax” e perché diventa tale, aiutandoci con l’osservazione sociologica tale da offrire dei riferimenti utili al miglioramento del servizio dedicato al turismo e al tempo libero. giungendo in un nuovo posto, sia per vacanza che per lavoro, mettiamo in funzione una serie di meccanismi di percezione che abbiamo insiti in noi. ciò che percepiamo innanzi tutto è la forma della costruzione, poi il colore dello stabile che ci comunicherà varie sensazioni, ed infine l’aspetto “tattile” cosi chiamato anche se riguarda, oltre che il toccare anche l’effetto visivo della superficie. tutto questo procedimento del nostro cervello avviene molto rapidamente, mentre è piuttosto lunga e complessa la realizzazione di un progetto efficace per una buona ricezione turistica. proviamo ad immaginare un albergo con linee architettoniche in stile mediterraneo che ricorda le bellissime case della spagna sulla costa del sol o sulla costa brava. dove l’occhio confonde la sua memoria con i profumi e con i colori dedicati alla delicatezza dei pastelli o dei gelati alla frutta. non è possibile non avere delle reazioni di desiderio stanziale, fermarsi per riposarsi e cogliere dentro di sé tutto ciò che sfugge in un altro contesto metropolitano. far sì che la clientela si fermi e che ritorni deve aiutarci a focalizzare l’obiettivo ultimo di un buon progetto di management del turismo. questi che stiamo elencando e descrivendo non sono altro che degli strumenti opportuni per avere dai fruitori degli stessi un riscontro valido sul piano della fidelizzazione e del “passa-parola positivo”. entrando più nello specifico verranno qui tracciati dei riferimenti sulla comunicazione del colore negli ambienti interni e come ottimizzare la resa estetica della struttura di cui disponiamo. il rosso è fra tutti il colore più dinamico, in grado di catturare l’attenzione visiva a discapito delle altre tinte. e’ stimolante ed eccitante, legato anche all’aggressività, collera, ferocia. il rosso crea l’illusione che gli oggetti siano più vicini di quanto non siano nella realtà, per effetto creato dal cristallino dell’occhio nel focalizzare tale colore. difficilmente viene impiegato come tinta principale di un locale. se il soffitto è tinto di rosso si avverte fastidio e pesantezza, se ne vengono tinteggiate le pareti, si percepirà aggressività. sul pavimento ispira attenzione, consapevolezza, talvolta pomposità. il marrone è un colore molto presente nella natura ma non è un colore dello spettro solare. è legato a concetti di comodità e di sicurezza, suggeriti dal colore della madre terra, richiama cose buone come la cioccolata e il caffè. se invece ha tonalità molto scure può suggerire sporcizia o tristezza. l’uso del marrone crea effetti differenti a secondo che sia il colore caldo del legno o una pittura artificiale. posto sul soffitto risulta opprimente e pesante, a parete infonde sicurezza e affabilità, sul pavimento richiama il senso dell’equilibrio. il giallo è tra i colori dello spettro solare quello più felice e luminoso, evoca il sole che genera la vita, è simbolo di speranza e di saggezza. e’ comunicativo, non a caso uno dei colori più usati in pubblicità. soprattutto nelle sue sfumature pastello, rende un ambiente vivace e spensierato, si armonizza bene con gli altri colori presenti e illumina gli ambienti piccoli. se tingiamo il soffitto di giallo otteniamo un effetto luminoso e stimolante, se lo adottiamo per le pareti comunichiamo calore, per il pavimento avremo un senso di elevazione. il verde è il colore che più è legato alla natura e quindi alla fertilità e alla crescita rigogliosa, quando tende al giallo risulta allegro, stimolante e luminoso; se invece tende al blu risulta prezioso, freddo e delicato. in contrapposizione risulta anche il colore della muffa, della decomposizione, della malattia. comunque induce al rilassamento ed è il tono più riposante per la vista poiché l’occhio lo focalizza perfettamente sulla retina. se il soffitto è tinto di verde ispira protezione, ma può creare brutti riflessi sulla pelle, sulle pareti avvertiremmo un senso di freschezza, calma, affidabilità, passività. sul pavimento il verde offrirà una sensazione di rilassamento e 24 cultura e scienza del colore color culture and science | 01/14 delicatezza. il blu è il colore che più piace e più induce al rilassamento. ad esso sono accostate le impressioni positive quali la calma, sicurezza, contemplazione, saggezza. la veste dei filosofi dell’antica roma era blu, blu la santità per gli ebrei, blu l’immortalità per la cina, blu il manto della madonna. in tutti i colori c’è l’interpretazione antagonista che viene codificata dalla tonalità, in questo caso troviamo la tristezza, la malinconia e lo struggimento. può risultare opprimente e assai freddo quando è utilizzato per tingere ampie porzioni di superficie. il blu pallido se dato al soffitto risulta fresco e celestiale, se assume sfumature scure crea un senso di pesantezza. alle pareti il blu chiaro conferisce un aspetto fresco e distante, il blu scuro dona una maggiore profondità all’ambiente. il pavimento blu chiaro crea la sensazione di muoversi senza sforzo, se è colorato di blu scuro sembra creare resistenza. il viola composto dal blu con il rosso, è associato all’idea della regalità ed eleganza ma anche al lutto e alla solitudine, simboleggia la ricchezza ma anche il misticismo e la magia. è scarsamente impiegato per tingere spazi interni, può indurre turbamento e soggezione. il bianco è il colore dell’innocenza, della purezza, della luce, della spiritualità. in architettura fa da padrone in particolare per gli interni. chiamato anche non colore se dato a soffitto crea un senso di vuoto, ma aiuta a diffondere la luce e mitiga le ombre, se dato alle pareti risulta neutro, sterile, fiacco. infine posto sul pavimento sembra inibire il camminarci sopra. il nero è il colore accostato a percezioni negative: rappresenta la paura, l’ignoto, il male, il dolore. altresì indica eleganza e lusso, ha la qualità di illuminare le altre tinte compreso il colore della pelle, da qui la preferenza delle signore ad indossare il nero, trasformandolo in simbolo di seduzione. anche per l’arredamento d’interni, si rivela estremamente elegante. posto sul soffitto induce oppressione, alle pareti inquietudine ed è stravagante se messo al pavimento. il grigio è il colore sospeso tra luce e oscurità, infonde tranquillità calma ma risulta essere pure lugubre e noioso, è il simbolo di ciò che è a metà strada, manca di vitalità. negli interni non apporta benefici, al soffitto risulta ombroso, alle pareti tedioso e monotono, al pavimento neutro. 5. vivere a colori affascinati, attratti, influenzati da piccoli particolari che spiccano tra gli oggetti di una vetrina o in una casa, fino al punto di desiderare di possederli. ne gode lo sguardo, abbagliato dai riflessi, accarezzato dai colori e dalla loro lucentezza. il colore ha una evidente influenza su ognuno di noi fino al punto di poter curare o prevenire l’insorgere di disturbi psico-somatici. la terapia del colore o cromoterapia, usa i differenti colori per cambiare o mantenere le vibrazioni del corpo alla frequenza della salute, del benessere, dell’armonia. i raggi colorati possono essere visibili o invisibili all’occhio umano e possono essere applicati al corpo sia fisicamente, attraverso l’esposizione ai raggi di luce, sia mentalmente, attraverso tecniche di suggestione, visualizzazione o meditazione. immaginate quindi l’importanza del colore delle stanze dove abitate, in virtù del tempo che vi trascorrete ora e della tendenza di viverci per più ore ( es. residence, albergo). la terapia del colore fu probabilmente il primo tipo di cura usato dall’uomo come mezzo naturale per mantenere l’organismo in equilibrio e armonia. l’uomo primitivo, pur non avendo la conoscenza e la capacità tecniche dell’uomo moderno, riusciva con saggezza a vivere secondo le perfette leggi della natura. il colore e la luce sono sempre stati una componente essenziale della vita e della nostra presenza sul pianeta. ciò detto ci spinge ad approfondire il nostro personale rapporto con il colore. la vostra personalità è la prima cosa che dovete prendere in considerazione quando definite il vostro schema dei colori. potete rielaborare le informazioni acquisite grazie alla lettura riflessa dei colori in modo da redigere uno schema cromatico specifico per voi. qui di seguito potete trovare una serie di domande preparatorie: che genere di attività dovrà svolgersi in questa stanza? quanta luce entra? e’ una zona fondamentalmente chiara o scura? qual è il suo colore naturale? osservate se si tratta di legno, mattoni o pietra. volete creare un ambiente stimolante e brillante, o lo preferireste calmo e tranquillo? volete un’atmosfera essenzialmente fredda o calda? il soffitto è alto o particolarmente basso? vorreste ampliare le dimensioni di questa stanza, o vi piacerebbe che fosse più piccola? qual è la forma di questo locale? è stretto e lungo, o corto e largo? con questi brevi accorgimenti potrete adeguare la struttura ricettiva alle profonde necessità fisiche e mentali della clientela, evitando la convinzione di dover cambiare sostanzialmente le camere per poter migliorare il confort. 6. conclusioni: il linguaggio dei colori nella sociologia del turismo il colore e la luce sono gli elementi che esercitano il maggiore impatto psicologico e fisiologico sull’ambiente, e conseguentemente sociologico, e influenzano l’organismo umano sia per l’aspetto visivo sia per quello non visivo. nessuno può incontrare un colore e rimanerne 2501/14 | cultura e scienza del colore color culture and science indifferente! davanti ad esso abbiamo una reazione immediata, istintiva ed emotiva, con piacere o fastidio, calore o freddezza, simpatia o antipatia. la fisica insegna che il colore non è altro che una particolare lunghezza d’onda la quale un oggetto genera o riflette, e che viene trasmessa dalle terminazioni nervose ai centri cerebrali che ne danno la percezione. il fenomeno fisico non esclude che il nostro primo approccio con il colore sia sempre di tipo psicologico, nella sfera del conscio, del subconscio o dell’inconscio. questo perché il colore è dentro ognuno di noi e può originare dalla forza di immaginazione del nostro universo interno. oltre l’impatto psicologico personale, esistono influenze culturali e consuetudini, vale a dire l’ascendenza che il colore ha avuto e ha sulle culture, sugli usi e sui costumi dei popoli. i giapponesi amano i colori che più sono legati all’acqua, al cielo, agli alberi; gli indiani prediligono le tinte più accese mentre gli svedesi preferiscono i colori sfumati che ritengono più eleganti. l’influenza cromatica sulle nostre culture può fornirci validi suggerimenti per l’ambiente progettato. il fattore più mutevole nella percezione del colore comprende le tendenze di gusto, le mode e gli stili. cambiare gusti e tendenze permette di sfuggire alla monotonia, ma bisogna prestare attenzione a non soffocare la libertà individuale in nome di una tendenza o di una moda. seguire attentamente tutto ciò che i guru del design e delle tendenze propongono, potrebbe significare, nel mondo della ricettività turistica, avere un effetto contrario all’incremento del fatturato. sintetizzando si può affermare che il colore è una forma di energia che agisce sulle funzioni del nostro corpo (attività cerebrale, sistema nervoso autonomo, attività ormonale) e contemporaneamente stimola associazioni estetiche ed emotive. esso agisce non solo sulle emozioni ed impressioni oggettive e soggettive, ma influenza la nostra concezione di volume, temperatura, peso, tempo e perfino umore. la tinta ha un proprio linguaggio riconosciuto universalmente ed è importante che chi opera nel management turistico sappia coordinare le consulenze dei design. è utile conoscere le associazioni e le caratteristiche tipiche di ogni gradazione tonale. sì alla globalizzazione, ma essa è composta dalle individualità che rendono riconoscibile la bellezza e l’arte delle diverse terre. comprendere i gusti e i costumi degli altri popoli serve per poter dare loro l’ospitalità e l’accoglienza opportuna, senza però perdere le tracce della nostra ricchissima storia antica. bibliografia colore e architettura di lorenzo cremonini alina editrice s.r.l. – firenze 1992 architettura bio-ecologica di maurizio corrado dve italia s.p.a. – milano 2000 architettura in pietre a secco di a. ambrosi,e. degano, c. a. zaccaria. schena editore fasano (br) il colore vissuto di magda di renzo ed. scientifiche magi srl – roma 1998 cromoterapia di osvaldo sponzilli edizioni mediterranee – roma 1998 cultura e scienza del colore color culture and science 132 cultura e scienza del colore color culture and science | 10 | 2018 | lecca m. and da pos o. issn 2384-9568 1michela lecca lecca@fbk.eu 2osvaldo da pos osvaldo.dapos@unipd.it 1fondazione bruno kessler, ict, technologies of vision, trento, it; 2università degli studi di padova, italia communications and comments in this column, prof. da pos reports some considerations from the talk he gave during the munsell 2018 international congress, held in boston last june to celebrate the centennial of the munsell color system. briefly, we remind that munsell system is a colour space where colours are characterized by hue, lightness and chroma identified by decimal numbers. this colour space, introduced at the beginning of 1900 was officially adopted for researches on soil in 1930, and still today is known and used all over the world. the talk of prof. da pos was not directly related to technical features of the munsell system, but it coped with the more general problem of the meaning and the relationships among colour perception, stimuli, and colour terminology, that we partially investigated in our previous column. in the following, prof. da pos discusses about these concepts and about the need and difficulties to define a colour system capable to capture and relate the three fields of research, often studied separately, colorimetry, perception, and verbal language. a new theory of perception is then highlighted to explain the nature of (perceived) colours and their relationships with the physical world. ----as is probably known, last june the munsell 2018 international congress was held in boston to celebrate the centennial of the homonymous colour system. a series of important keynote talks started a week of extremely rich works from both the scientific and the artistic point of view. i was invited, to my great surprise, to keep one of the introductory talks on the subject, expressly requested, ‘colour names, stimulus colour, and their subjective link’ [1]. the lecture seems to have fully met the expectations of those who had invited me and the interest of the audience. i asked myself: why this interest in a subject that apparently is only collateral to the munsell system? the answer i gave is already somehow present in the previous edition of this column, namely that the research in question clarifies the fundamental relationships between physical stimuli, colour perception and verbal language of colour, relationships that are often only implicitly assumed in colour studies or even misunderstood (figure 1). the assumption of the research is that perception is essentially subjective and conscious, and we can discuss about it not only because we have direct experience, but we can formulate it verbally so as to reflect on it as an object, independent from our subjectivity; secondly, the verbal formulation, although limited, also allows us to communicate the subjectively perceived colour to others. however, this is not the only way to objectify a subjective impression of “psychological colour space is the relational structure among colours colour stimuli that can be found using empirical tasks that assess colour similarities. colour terms are the lexical categories (which can vary across different ethnolinguistic groups) that are used to label, or describe, colour appearances organized as meaningful partitions of the psychological colour space.” (from: encyclopedia of color science and technology https://link.springer.com/referencework/10.1007/978-1-4419-8071-7#toc) column 133 cultura e scienza del colore color culture and science | 09 | 2018 | coloumn. communications and comments issn 2384-9568 colour, because we can also act on the physical world and produce (or eventually choose) a set of stimuli that induce the perception of the same colour in other people. while in the first case, using a verbal term to describe a colour, perception and linguistic formulation are both present in our consciousness, in the second case physical stimulation and perception are not both conscious, but only the perception is. the stimulus colour, on the other hand, can be known only through scientific knowledge, essentially psychophysics and in particular colorimetry. the link between a particular stimulus colour and the corresponding perceived colour, not being conscious, can only be inferred with a limited degree of certainty: is it true that i and the others have the same colour impression when we look, under the same observing conditions, an object? (perceived object, of course). a recent theory about the relationships presented here has been formulated by d.d. hoffman et al. in the form of ‘interface theory of perception’ [2]. the theory essentially says that perception has the function of inducing in the individual a behaviour that is adaptive with respect to the physical environment. this function is accomplished by producing, both in man and in the animal, a phenomenal world, the one that appears around us and of which we are aware: this is an interface between us and the physical environment. perception therefore has no cognitive purpose, it is not intended to make us know the ‘physical reality’ as it is, but it is a simplification of our interaction with the environment as it draws from the physical world the information needed to build a subjective world with the essential characteristics to adapt to the environment. it is like the interface of a computer that shows the operator a set of icons on which it acts to accomplish something that affects the physical level, but without knowing its modality. in fact, a person can use the computer effectively without having to know anything about what is beyond what he sees. contrary to what happens in animals, in man perception is accessible to rational knowledge, which can therefore not only verbalize what one “sees” in order to be able to reason on it, but can arise questions about its meaning (how it works) to give answers that satisfy his curiosity and his needs. this further step can fix those unavoidable mistakes (in relation to the adequacy of its outcomes as respect to the environment requirements) which perception, being an approximate capability can sometimes encounter: where animal failure brings to death, science and technology increase human fitness. the colour is therefore an aspect of this interface, and as such it cannot be considered true, but only useful (a yellow icon does not mean at all that the bit sequence 00101001110101 to figure 1 what’s the relationship between color perception, stimuli and terminology? this topic has been discussed by prof. da pos at the munsell 2018 international congress, held this year in boston, usa 134 cultura e scienza del colore color culture and science | 10 | 2018 | lecca m. and da pos o. issn 2384-9568 which it is pointing is yellow). long ago i maintained that our colours are pseudo colours, or falsecolours, that is colours artificially produced to make us ‘see’ something where events otherwise unreachable by our perception are occurring, and therefore allow us to perform the appropriate behaviours. ultrasound is a clear example where false colours are used: the colours that this technique shows the observer are not characteristics of the filmed objects or events, clearly unreachable by our perception. on the contrary, they are colours produced by algorithms that experienced engineers and psychologists have decided to attribute to the images displayed on the screen, on the basis of their operational efficacy to achieve specific purposes. the assumptions of this theory are not entirely new, for example the perception of [chromatic] colour brings an evolutionary advantage to the species that possess it compared to those that do not possess it, despite the colour stimulus be the same for both [3]. in other words, a good software with suitable icons performs better than a poor software with few or inefficient icons, while the physical realm is the same. colour vision is therefore an enhancement of animal capability to fit the environmental requirements. the gain in fitness is not so absolute as it would be obtainable by a perfect knowledge of the physical world, but it is enough appropriate as its cost is much lower. the objects and events that occur in the phenomenal world (that is, in the interface man / physical environment) have their own internal logic that can be studied regardless of their link with the underlying physics. this kind of study is performed by the phenomenology of perception, which investigates the characteristics of this world of appearances by finding their reasons in specific relations between elements within it. for example, the impression of transparency that a coloured surface can produce in the observer is explained phenomenologically as follows: the colour of the overlapping area of that surface with another below must be a psychologically intermediate colour (that is it must look like both) between the colour of the overlying surface and that of the underlying surface one [4]. as can be seen, what is treated in the study of perceptive transparency are colours and relationships of similarity between colours, properly quantified but always at a perceptual level. moreover perceptive transparency does not necessarily derives from physical transparency, although sometimes this happens, but its occurrence only depends on chromatic and configurational properties of the image. this way of interpreting perception in general, and colour perception in particular, as an interface between subject and physical environment, seems to constitute a paradigm shift in current colour science [5]. many authors are enthusiastic about this, but there is no shortage of criticism, especially regarding some details of the theory [6]. bibliography [1] liliana albertazzi, osvaldo da pos 2017 color names, stimulus color and their subjective links. color research and application vol. 42, iss. 1, pp. 89-101. s [2] donald d. hoffman, manish singh, chetan prakash. 2015 interface theory of perception. psychonomic bulletin & review. vol 22 (6), pp 1480–1506. https://doi. org/10.3758/s13423-015-0890-8 [3] john d. mollon. 1989 “tho’ she kneel’d in that place where they grew ...”. the uses and origins of primate colour vision. j. exp. biol. 146, 21-38 [4] o. da pos, trasparenze, transparency, milano: icone, 1989 [5] gregory hickok 2015 editorial: the interface theory of perception: the future of the science of the mind? psychon bull rev (2015) 22:1477–1479 doi 10.3758/s13423-0150930-4. [6] hoffman, d.d., singh, m. & prakash, probing the interface theory of perception: reply to commentaries. c. psychon bull rev (2015) 22: 1551. https://doi.org/10.3758/ s13423-015-0931-3 cultura e scienza del colore color culture and science 4 cultura e scienza del colore color culture and science | 03/15 1maria francesca alberghina maria.alberghina@unipa.it 1rosita barraco rosita.barraco@unipa.it 1,2maria brai maria.brai@unipa.it 3lorella pellegrino pelegelino@libero.it 4fernanda prestileo f.prestileo@icvbc.cnr.it 5salvatore schiavone info@start-test.it 2luigi tranchina luigi.tranchina@unipa.it 1dipartimento di fisica e chimica, università degli studi di palermo 2uninetlab, università degli studi di palermo 3laboratorio di restauro manufatti di origine inorganica, centro regionale per la progettazione e il restauro, regione siciliana, palermo 4consiglio nazionale delle ricerche, istituto per la valorizzazione e la conservazione dei beni culturali, roma (già centro regionale per la progettazione e il restauro, regione siciliana, palermo) 5s.t.art-test s.a.s, niscemi (cl) impiego della principal component analisys per l’analisi statistica su dati colorimetrici di tessere musive pavimentali progetto con sorgenti colorate al neon 1. introduzione il progetto di recupero e conservazione del complesso archeologico della villa romana del casale (piazza armerina, enna) [1], avviato nel 2007 e ultimato nel 2012 a cura del centro regionale per la progettazione e il restauro di palermo (c.r.p.r.), ha previsto, tra le tecniche diagnostiche per il monitoraggio dell’intervento, l’acquisizione di misure spettrofotometriche, allo scopo di controllare l’eventuale variazione delle coordinate cromatiche [2-5] dovuta agli interventi di pulitura e di consolidamento delle superfici musive pavimentali della villa [6]. ciò ha posto gli operatori di fronte alla necessità di individuare uno strumento analitico in grado di gestire un elevato numero di dati e di fornire un quadro sinottico funzionale per una migliore comprensione del comportamento cromatico dei materiali a seguito delle fasi dell’intervento e delle variazioni nel tempo. in questo contesto si intende evidenziare come l’analisi di dati spettrofotometrici possa rappresentare un utile strumento conoscitivo per il restauratore, coadiuvandolo nelle scelte operative. un impiego efficace delle informazioni così fornite dipende però dall’immediatezza e dalla facilità di lettura dei dati anche da parte degli operatori degli interventi di restauro, per i quali le tematiche riguardanti la misura del colore e la sua rappresentazione spesso non sono familiari. per ovviare a tale inconveniente, e quindi valutare nella maniera più immediata e corretta gli effetti generati sulle superfici in seguito ai trattamenti di pulitura e di consolidamento, l’analisi delle componenti principali (pca – principal component analysis) è stata applicata ai dati colorimetrici acquisiti sulle tessere musive, proponendo in tal modo una possibile lettura più intuitiva dei fenomeni generati dalle variazioni colorimetriche. in generale la pca viene impiegata in differenti campi applicativi: per esaminare la variabilità spaziale di contaminanti, nel caso di analisi ambientale [7]; per valutare l’entità e la distribuzione di fenomeni di degrado, nel caso di indagini diagnostiche nel campo dei beni culturali; come anche, più di recente, per il monitoraggio delle variazioni cromatiche di superficie di diversa tipologia sottoposte a trattamenti di pulitura, consolidamento e/o figura 1 – villa romana del casale di piazza armerina: planimetria con localizzazione delle stanze (evidenziate in grigio le stanze 4f, 30, 33, e 40) all’interno delle quali sono stati acquisiti i dati colorimetrici per il monitoraggio delle superfici musive. 503/15 | cultura e scienza del colore color culture and science protezione [8]. come esempio esplicativo di quest’ultimo utilizzo, viene qui presentato quello dell’indagine colorimetrica eseguita su alcune porzioni campione della pavimentazione realizzata a tessere musive della stanza della piccola caccia (stanza 30) della villa, scelta quale area campione dell’intervento pilota di pulitura della superficie musiva, realizzato mediante impacchi di carbonato d’ammonio, nonché di differenti aree musive delle stanze frigidarium (4f), stanza a mosaico a riquadri (33) ed esedra (40), scelte per il monitoraggio del trattamento protettivo tramite impacchi di ossalato di ammonio (figura 1). i valori colorimetrici, di seguito riportati, sono stati acquisiti sia prima che dopo i trattamenti, misurando i dati spettrofotometrici relativi alle fasi di ciascun trattamento. lo studio condotto ha evidenziato le potenzialità della pca, permettendo di valutare in maniera immediata e corretta gli effetti generati sulle superfici a seguito dei trattamenti di restauro ed evidenziando la correlazione esistente tra le variazioni delle tre variabili l*, a* e b*, relative ai dati colorimetrici acquisiti prima e dopo gli interventi. nel caso delle tessere della stanza piccola caccia la distribuzione in cluster dei dati proiettati in un piano bidimensionale, evidenziata dalla pca, ha consentito di individuare più chiaramente la variabile che, in seguito alla pulitura, contribuisce maggiormente al viraggio cromatico. inoltre, grazie al raggruppamento in cluster dei dati è stato possibile monitorare, in maniera differenziata, il comportamento in superficie di tessere musive, aventi colore differente, sottoposte allo stesso trattamento di pulitura. l’obiettivo applicativo della pca è stato, infatti, quello di valutarne l’efficienza analitica nell’interpretare i fenomeni sulla superficie musiva, dovuti non solo alla pulitura ma anche ai trattamenti di consolidamento e protezione. 2. materiali e metodi le misure sono state effettuate mediante impiego di uno spettrofotometro portatile minolta modello cm 2600d. per ciascuna area campione degli ambienti oggetto di analisi sono state realizzate delle maschere in acetato sulle quali sono stati riportati alcuni punti di riferimento, al fine di assicurare la ripetibilità delle misure nel tempo, così come riportato in figura 2.a-b per la stanza 30 [2-5, 9-10]. per effettuare le misure lo strumento è stato settato con i seguenti parametri: media auto 3 (numero delle misure eseguite su uno stesso campione e relativo valore medio); tempo di misura 0,3 secondi (tempo di presa); area di lettura “s” (circolare, con diametro efficace di 3 mm); sci (componente speculare inclusa); figura 2 – piccola caccia (stanza 30): a) posizionamento della maschera a, punti di misura da 1a a 17a; b) posizionamento della maschera b, punti di misura da 1b a 23b. a) b) 6 cultura e scienza del colore color culture and science | 03/15 illuminante primario d65; osservatore normale 10°. lo spazio del colore adottato è quello l* a* b* δe (cie 1976) [11-12], più comunemente impiegato nel campo del restauro. durante le misure è stata rilevata la temperatura ambientale. i dati colorimetrici acquisiti sono stati elaborati tramite pca. la tecnica di analisi delle componenti principali permette di visualizzare, in uno spazio bidimensionale, una matrice di dati multidimensionale, caratterizzati quindi da più di due variabili, identificando la distribuzione dell’insieme di dati ed evidenziando similarità e/o differenze tra questi. la pca, infatti, è una tecnica di riduzione delle variabili in base alla quale le nuove variabili (componenti principali o fattori) vengono calcolate dalle combinazioni lineari delle variabili originali, ossia, nel caso specifico, le tre coordinate colorimetriche l*, a* e b*. ciascuno dei fattori ricavati dall’analisi spiega una parte della varianza dei dati. in particolare, il primo fattore spiega una maggiore percentuale di questa varianza rispetto al secondo e così via fino all’ultimo; in maniera tale che il 100% della varianza venga spiegato da un numero di fattori pari al numero delle variabili analizzate. i factor loadings sono invece rappresentati dai coefficienti di correlazione esistenti tra le variabili originali ed i fattori ricavati. questi sono generalmente utilizzati per investigare i processi che controllano la variabilità nei dati. la rappresentazione grafica rende di immediata comprensione l’interpretazione dei risultati ottenuti da questo tipo di analisi multivariata [78]. 3. analisi dei dati colorimetrici vengono di seguito riportati i dati spettrofotometrici acquisiti prima e dopo le fasi di pulitura sulle tessere della piccola caccia, corrispondentemente a ciascuna delle due zone indagate. per quanto riguarda la porzione musiva in corrispondenza della maschera a, dal confronto dei valori colorimetrici dei punti campione acquisiti prima della pulitura e di quelli relativi agli stessi punti misurati dopo la prima fase consistente in impacchi di carbonato di ammonio, è stato possibile rilevare la presenza di forti variazioni cromatiche dovute soprattutto ad un aumento della luminosità l* e, in quasi tutti i casi, una leggera diminuzione dei valori colorimetrici a* e b*, come mostrato dalle differenze calcolate e riportate in tabella 1 e dal grafico in figura 3. le medesime considerazioni valgono per le variazioni osservate nei punti di misura dell’area in corrispondenza della maschera b, tra i valori acquisiti prima della pulitura e quelli misurati dopo gli impacchi di carbonato d’ammonio, riportati nel grafico di figura 4. anche in questo caso, i valori di δe sono spiegabili con un aumento della luminosità ed una diminuzione della saturazione, come si evince dai dati di variazione cromatica riportati in tabella 2. infine, nel grafico di figura 5, nel quale sono presi ad esempio i “rossi” e gli “incarnati”, è chiaro che il trattamento a carbonato di ammonio non ha causato alcuna modifica dell’andamento della curva di riflettanza (%) alle varie lunghezze punti di misura sigla δl* δa* δb* δe punto 1a incarnato 1a_i 10.97 2.77 -4.61 12,22 punto 2a incarnato 2a_i 6.08 -2.46 -6.17 9,00 punto 3a rosso 3a_r 2.12 2.00 -2.39 3,77 punto 4a bianco 4a_w 2.65 -0.21 -1.71 3,15 punto 5a verde 5a_g 15.54 -0.67 -2.13 15,70 punto 6a verde 6a_w 15.03 -0.68 -2.86 15,32 punto 7a bianco 7a_w 2.42 -0.18 -1.70 2,96 punto 8a verde 8a_g 16.74 -0.50 -2.41 16,92 punto 9a rosso 9a_r 7.75 -1.33 -3.30 8,53 punto 10a verde 10a_g 8.40 0.83 -3.23 9,04 punto 11a rosso 11a_r 6.64 -1.55 -2.79 7,37 punto 12a nero 12a_b 1.23 -0.10 -0.91 1,53 punto 13a nero 13a_b 2.53 -0.17 -1.67 3,04 punto 14a giallo 14a_y 4.16 -0.89 -3.76 5,68 punto 15a giallo 15a_y 2.46 -1.06 -4.45 5,20 punto 16a giallo 16a_y 9.04 -1.35 -2.32 9,44 punto 17a giallo 17a_y 5.19 0.61 2.89 5,97 tabella 1 variazione delle coordinate colorimetriche delle tessere musive relative ai punti di misura della maschera a (piccola caccia) ottenute in seguito al trattamento con carbonato d’ammonio. 703/15 | cultura e scienza del colore color culture and science d’onda nel visibile, ma ha apportato soltanto una variazione costante dei valori percentuali, lungo il range spettrale acquisito, uniformando la riflettanza (%) per tessere musive simili. 4. principal component analysis dei dati spettrofotometrici i valori delle coordinate colorimetriche acquisiti per ciascun punto campione, prima e dopo i trattamenti, sono stati successivamente analizzati statisticamente tramite pca. i dati colorimetrici sottoposti ad analisi statistica, oltre a quelli già presi in considerazione nel paragrafo precedente relativi alla piccola caccia (stanza 30), sono stati acquisiti in corrispondenza di differenti aree musive delle stanze frigidarium (4f), stanza a mosaico a riquadri (33) ed esedra (40). la pca, dunque, è stata applicata all’analisi di due casi studio: 1) valutazione degli effetti cromatici conseguenti agli interventi di pulitura (figura 6a); 2) monitoraggio del trattamento protettivo tramite impacchi all’ossalato di ammonio (figura 6b) [2, 4-5, 10]. nel primo caso, allo scopo di evidenziare gli effetti della pulitura, sono state scelte due tipologie di tessere musive “acromatiche” (tessere bianche e nere) (figura 6a). in particolare, le misure sono state acquisite su aree campione selezionate all’interno delle seguenti stanze: 4f, 30, 33 e 40. prima e dopo la pulitura, i valori delle coordinate colorimetriche l*, a* e b*, acquisiti per ognuno dei punti campione, sono stati analizzati statisticamente tramite pca (figura 7). le due componenti principali (f1 e f2) isolate dall’analisi multivariata spiegano complessivamente il 97% della varianza dei dati. in particolare, il fattore f1 l’85% ed f2 il 12%. come atteso, l’analisi produce raggruppamenti (cluster) dei punti campione differenziando chiaramente i bianchi dai neri: le variabili a* b* e l* mostrano valori più alti per i campioni bianchi (asse x positivo in fig. 7) e valori inferiori per i campioni neri (asse x negativo in figura 7). la presenza dei due macrocluster permette, quindi, di monitorare gli effetti di pulitura per singolo raggruppamento attraverso la correlazione esistente tra le variazioni delle coordinate cromatiche. per quanto riguarda il cluster relativo alle tessere nere, la pca rivela un’ulteriore raggruppamento dei dati (prima e dopo la pulitura) per stanza di appartenenza (stanze 30, 33). i punti appartenenti alle misure effettuate nella stanza 40, data la loro l’esiguità, non possono considerarsi raggruppamento statisticamente significativo. per l’intero set di dati relativi alle tessere nere, la variabile che maggiormente evidenzia l’effetto della pulitura è l* che aumenta dopo il trattamento, a differenza delle altre due coordinate cromatiche pressoché costanti. si sottolinea, altresì, che l’aumento della luminosità punti di misura sigla δl* δa* δb* δe punto 1a incarnato 1a_i 10.97 2.77 -4.61 12,22 punto 2a incarnato 2a_i 6.08 -2.46 -6.17 9,00 punto 3a rosso 3a_r 2.12 2.00 -2.39 3,77 punto 4a bianco 4a_w 2.65 -0.21 -1.71 3,15 punto 5a verde 5a_g 15.54 -0.67 -2.13 15,70 punto 6a verde 6a_w 15.03 -0.68 -2.86 15,32 punto 7a bianco 7a_w 2.42 -0.18 -1.70 2,96 punto 8a verde 8a_g 16.74 -0.50 -2.41 16,92 punto 9a rosso 9a_r 7.75 -1.33 -3.30 8,53 punto 10a verde 10a_g 8.40 0.83 -3.23 9,04 punto 11a rosso 11a_r 6.64 -1.55 -2.79 7,37 punto 12a nero 12a_b 1.23 -0.10 -0.91 1,53 punto 13a nero 13a_b 2.53 -0.17 -1.67 3,04 punto 14a giallo 14a_y 4.16 -0.89 -3.76 5,68 punto 15a giallo 15a_y 2.46 -1.06 -4.45 5,20 punto 16a giallo 16a_y 9.04 -1.35 -2.32 9,44 punto 17a giallo 17a_y 5.19 0.61 2.89 5,97 figura 3 grafico l*a*b* delle coordinate colorimetriche delle tessere musive relative ai punti di misura della maschera a (piccola caccia) prima e dopo il trattamento con carbonato d’ammonio. figura 4 grafico l*a*b* delle coordinate colorimetriche delle tessere musive relative ai punti di misura della maschera b (piccola caccia) prima e dopo il trattamento con carbonato d’ammonio. figura 5 curve di riflettanza spettrale (%) relative ai punti di misura 1-4, 12, 13, 22, 23 della maschera b prima (linea continua) e dopo il trattamento con (nh 4 ) 2 co 3 (linea tratteggiata). 8 cultura e scienza del colore color culture and science | 03/15 punti di misura sigla δl* δa* δb* δe punto 1b rosso 1b_r 5.64 -1.62 -2.69 6,46 punto 2b rosso 2b_r 5.05 -1.62 -0.81 5,36 punto 3b rosso 3b_r 0.99 -0.44 -7.23 7,31 punto 4b rosso 4b_r 5.30 -0.11 -3.68 6,46 punto 5b verde 5b_g 11.99 -0.36 -2.88 12,34 punto 6b nero 6b_b -3.31 -0.29 -2.14 3,95 punto 7b nero 7b_b 5.07 -0.35 -1.91 5,43 punto 8b verde 8b_g 12.05 0.52 -1.69 12,18 punto 9b giallo 9b_y 2.17 -0.98 -5.38 5,89 punto 10b verde 10b_g 10.60 0.76 -0.46 10,64 punto 11b bianco 11b_w 1.99 -0.27 -3.10 3,69 punto 12b incarnato 12b_i 5.95 -1.67 -4.59 7,70 punto 13b incarnato 13b_i 5.87 -1.93 -4.19 7,47 punto 14b bianco 14b_w 2.99 -0.51 -4.03 5,04 punto 15b giallo 15b_y 7.88 -1.15 -4.55 9,17 punto 16b giallo 16b_y 6.87 -4.32 -9.68 12,63 punto 17b verde 17b_g 5.64 -2.16 -2.93 6,71 punto 18b verde 18b_g 13.81 -2.15 -0.81 14,00 punto 19b nero 19b_b 7.08 -0.51 -2.48 7,52 punto 20b nero 20b_b 6.32 -0.07 -0.16 6,32 punto 21b giallo 21b_y 3.83 -3.75 -9.67 11,06 punto 22b rosso 22b_r 4.73 -2.92 -4.51 7,16 punto 23b rosso 23b_r 7.03 -3.43 -4.91 9,24 tabella 2 variazione delle coordinate colorimetriche delle tessere musive relative ai punti di misura della maschera b (piccola caccia) ottenute in seguito al trattamento con carbonato d’ammonio. è correlabile ad un miglioramento delle proprietà ottiche delle superfici in seguito all’intervento. nel caso delle tessere bianche, non è possibile distinguere le stanze all’interno del macrocluster. la pca mostra gli effetti della pulitura attraverso la simultanea diminuzione di a* e b*, correlabile ad una decolorazione delle tessere (rimozione di depositi superficiali) ed un aumento di l* conseguente all’aumento della luminosità. il secondo caso studio ha riguardato l’analisi pca di dati inerenti tessere musive di differenti cromie (rosso, rosa, giallo e varie tonalità di verde) (fig. 6b) acquisite in tre differenti intervalli temporali dal trattamento (i fase: subito dopo; ii fase: dopo 11 mesi; iii fase: dopo 41 mesi). per facilitare la lettura degli effetti del trattamento protettivo, la pca è stata effettuata separando i dati appartenenti alle tessere rosse, rosa e gialle (primo gruppo) da quelle di cromia verde (secondo gruppo). oltre le coordinate colorimetriche l*, a* e b*, nella pca sono stati considerati anche i valori misurati di c, h, ed i valori, calcolati nel range 400 nm 700 nm, sia dell’integrale della curva di riflettanza (i (r%) ) che della lunghezza d’onda in nm corrispondente al valore massimo della derivata (λ nm). l’utilizzo a) b) figura 6 villa romana del casale: a) area campione stanza 33, maschera c: esempio di tessere bianche e nere sottoposte al trattamento di pulitura; b) area campione stanza 30, maschera f: esempio di tessere musive di differente cromia trattate con ossalato d’ammonio. 903/15 | cultura e scienza del colore color culture and science delle variabili i (r%) , λ nm, più significativo in questo caso che per le tessere bianche e nere, nasce dalla necessità di monitorare la curva di riflettanza (%) in termini rispettivamente di area e di andamento nell’intero range spettrale di interesse. nel primo gruppo di cromie, le componenti f1 e f2 spiegano complessivamente il 92.45% della varianza dei dati (figura 8). la pca di questo gruppo separa le tessere per cromia, distinguendo rossi, rosa e gialli ed evidenziando la maggiore omogeneità, in termini di andamento della curva di riflettanza (%), dei rossi e dei rosa rispetto al cluster dei gialli. in generale, per quanto riguarda il monitoraggio del trattamento nelle tre fasi di misura, l’analisi mostra la tendenza ad un riavvicinamento ai valori spettrofotometrici misurati subito dopo il trattamento, dopo un iniziale allontanamento registrato in corrispondenza della ii fase. questo comportamento sembra suggerire la presenza di un’alterazione che influenza le proprietà ottiche della patina di trattamento le cui peculiarità dovranno essere evidenziate da specifiche analisi chimico-fisiche. ulteriori dati temporali intermedi avrebbero permesso una valutazione più significativa dell’evoluzione del figura 7 grafico pca: confronto tra i valori acquisiti prima (simboli vuoti) e quelli acquisiti dopo l’intervento di pulitura (simboli pieni) per ognuno dei punti indagati. i simboli grafici sono identificativi delle stanze, in dettaglio: il quadrato identifica la stanza 33, il cerchio la stanza 30, il triangolo la stanza 40 ed infine il rombo la 4f (per la localizzazione vedi figura 1). le linee a punti individuano i cluster omogenei per colorazione (black a sinistra e white a destra), le linee tratteggiate raggruppano i punti appartenenti alle stesse stanze. figura 8 grafico pca rispetto alle variabili l*, a*, b*, c, h, i (r%) e λ nm: confronto tra i valori acquisiti subito dopo il trattamento protettivo (cerchio), dopo 11 mesi dal trattamento (triangolo) e dopo 41 mesi dal trattamento (quadrato). i colori dei simboli sono identificativi delle cromie: rosso, rosa e giallo. 10 cultura e scienza del colore color culture and science | 03/15 trattamento nel tempo. i dati relativi alle tessere di colore rosa, in funzione della fase di misura, si differenziano per una minore variazione riconducibile ad una probabile maggiore stabilità del trattamento. nella pca del secondo gruppo di cromie (differenti tonalità di verde), le componenti f1 e f2 spiegano complessivamente l’83.13% della varianza dei dati (figura 9). in questo caso, l’analisi statistica separa le tessere per tonalità di verde (verde scuro, verde chiaro e verde oliva, rispettivamente da sinistra verso destra), collocando in due semipiani distinti, perpendicolari all’asse di l*, i più chiari e i più scuri. in relazione al trattamento, per il cluster dei verdi scuri la tendenza generale è quella già riscontrata per i dati relativi al primo gruppo (figura 9). al contrario, per i rimanenti dati spettrofotometrici relativi agli altri due cluster, la iii fase rivela un ulteriore allontanamento dai valori che caratterizzano la i fase, molto più marcato nel caso dei verdi oliva. inoltre, questi ultimi in corrispondenza dell’ultima fase, risultano caratterizzati da una maggiore saturazione (spostamento verso valore positivi dell’asse x: aumento di a*, b* e c* e simultanea diminuzione di h e l*). 4. conclusioni l’analisi dei dati colorimetrici finora condotta ha evidenziato le potenzialità della pca, permettendo di valutare in maniera immediata e corretta gli effetti generati sulle superfici a seguito dei trattamenti di restauro e di approfondire le osservazioni deducibili dalla sola analisi dell’andamento dei valori delle coordinate colorimetriche e della riflettanza. dall’analisi dei risultati delle misure spettrofotometriche qui presentati è stato possibile rilevare, in seguito al trattamento di pulitura con impacchi di carbonato di ammonio, la presenza di variazioni cromatiche caratterizzate da un aumento della luminosità l* unitamente, in quasi tutti i casi indagati, ad una diminuzione della saturazione cromatica (a* e b*). la variazione dei valori di a* e b* potrebbe essere imputabile all’eliminazione dello strato di cera che, pur saturando i colori, aveva inglobato depositi di sporco con conseguente diminuzione della luminosità. è apparso evidente, inoltre, che il trattamento a carbonato di ammonio non ha causato alcuna modifica dell’andamento della curva di riflettanza (%) alle varie lunghezze d’onda nel visibile, ma soltanto una variazione dei valori percentuali, costante lungo il range spettrale acquisito, uniformando la riflettanza (%) per tessere musive simili (colore e rugosità superficiale). infatti, l’indagine condotta ha verificato e documentato la maggiore uniformità cromatica ottenuta grazie all’intervento di pulitura che ha permesso di eliminare i depositi che alteravano i reali valori di riflettanza (%) delle superfici musive. inoltre, questo studio, attraverso l’analisi statistica di un elevato numero di dati spettrofotometrici, ha permesso di monitorare, in maniera differenziata, il comportamento della superficie di tessere musive di cromia differente. la pca, infatti, si è rivelata un efficiente strumento analitico per valutare gli effetti di interventi di pulitura e trattamenti protettivi superficiali. inoltre, è stato possibile verificare la capacità della pca di facilitare l’interpretazione simultanea del comportamento delle variabili spettrofotometriche dell’intero set analizzato, raggruppando i dati per tipologia di cromia e figura 9 grafico pca rispetto alle variabili l*, a*, b*, c, h, i (r%) e λ nm: confronto tra i valori acquisiti subito dopo il trattamento protettivo (cerchio), dopo 11 mesi dal trattamento (triangolo) e dopo 41 mesi dal trattamento (quadrato). i colori dei simboli sono identificativi delle differenti tonalità di tessere verdi misurate. 1103/15 | cultura e scienza del colore color culture and science fase di misura. in generale, l’integrazione dei dati già analizzati con ulteriori dati provenienti da misure di tipo chimico-fisico (xrf, sem, ft-ir, etc.) potrebbe permettere di spiegare il comportamento spettrofotometrico evidenziato dalla pca e di individuarne le cause. ringraziamenti gli autori desiderano ringraziare l’arch. guido meli, già direttore del parco archeologico della villa romana del casale e delle aree archeologiche di piazza armerina e dei comuni limitrofi, e l’intero gruppo di lavoro del “progetto di restauro e conservazione della villa romana del casale”. il presente articolo è frutto del lavoro di revisione e integrazione dei due contributi presentati alla vi (lecce 2010) e alla vii (roma 2011) conferenza nazionale del colore, così come riportato in bibliografia. bibliografia [1] c.r.p.r., “progetto di recupero e conservazione della villa imperiale del casale di piazza armerina”, i quaderni di palazzo montalbo, i grandi restauri, n. 12/1, palermo, 2007. [2] m.f. alberghina, m. brai, l. pellegrino, f. prestileo, s. schiavone, l. tranchina, “analisi statistica tramite pca su dati colorimetrici di tessere musive pavimentali”, in m. rossi (a cura di), colore e colorimetria: contributi multidisciplinari, atti della vi conferenza nazionale del gruppo del colore, università degli studi del salento lecce, 16-17 settembre 2010, collana quaderni di ottica e fotonica, 19, maggioli editore, rimini, 2010, pp. 255-264. [3] f. prestileo, m.f. alberghina, s. schiavone, l. pellegrino, g. meli, d. perrone, “l’analisi colorimetrica a supporto dell’intervento di restauro sui mosaici della villa romana del casale di piazza armerina, in m. rossi (a cura di), colore e colorimetria: contributi multidisciplinari”, atti della vii conferenza nazionale del gruppo del colore, università degli studi sapienza, roma, 15-16 settembre 2011, collana quaderni di ottica e fotonica, 20, maggioli editore, rimini, 2011, pp. 429-436. [4] m.f. alberghina, m. brai, l. pellegrino, f. prestileo, s. schiavone, l. tranchina, “ulteriori valutazioni sull’impiego della principal component analysis su dati colorimetrici di tessere musive pavimentali”, in m. rossi (a cura di), colore e colorimetria: contributi multidisciplinari, atti della vii conferenza nazionale del gruppo del colore, università degli studi sapienza, roma, 15-16 settembre 2011, collana quaderni di ottica e fotonica, 20, maggioli editore, rimini, 2011, pp. 443-448. [5] m.f. alberghina, r. barraco, s. basile, m. brai, l. pellegrino, f. prestileo, s. schiavone, l. tranchina, “mosaic floors of roman villa del casale: principal component analysis on spectrophotometric and colorimetric data”, journal of cultural heritage, 15, pp. 92-97 (2014) [6] c. colombo, f. fratini, m. matteini, l. pellegrino, m. realini, s. rescic, l. rosi, “the mosaic paving of villa del casale (piazza armerina – en): proposal of conservation tratments”, atti del iii convegno internazionale la materia e i segni della storia. scienza e patrimonio culturale nell’area del mediterraneo, palermo, 18-21/10/2007, i quaderni di palazzo montalbo, n. 15, c.r.p.r., palermo, 2009, pp. 367-375. [7] tranchina, l., s. basile, m. brai, a. caruso, c. cosentino, s. micciché, “distribution of heavy metals in marine sediments of palermo gulf (sicily, italy)”, in water air and soil pollution, 191 (1-4), 2008, pp. 245-256. [8] g. luciano, r. leardi, p. letardi, “principal component analysis of colour measurements of patinas and coating systems for outdoor bronze monuments”, in journal of cultural heritage, 10, 2009, pp. 331–337. [9] e. cacciatore, f. prestileo, g. bruno, l. pellegrino, d. perrone, m. f. alberghina, s. schiavone, “monitoring the decorated surfaces of the roman villa del casale in piazza armerina (italy)”, in p. tiano, c. pardini (a cura di), proceedings of international workshop smw08 in situ monitoring of monumental surfaces, florence, 2729/10/2008, edifir edizioni, firenze, 2008, pp. 301-306. [10] f. prestileo, g. bruno, m. f. alberghina, s. schiavone, l. pellegrino, “i mosaici della villa romana del casale di piazza armerina: il contributo delle indagini colorimetriche per la stesura del protocollo di intervento”, in a. rizzi (a cura di), colore e colorimetria: contributi multidisciplinari, atti della iii conferenza nazionale del gruppo del colore, torino, 24-26/10/2007, collana quaderni di ottica e fotonica, 16, cet, firenze, 2007, pp. 45-55. [11] c. oleari (a cura di), “misurare il colore”, ed. hoepli, milano, 2002. [12] uni en 15886:2010, conservation of cultural property – test methods – colour measurement of surfaces. cultura e scienza del colore color culture and science 40 cultura e scienza del colore color culture and science | 03/15 2. materials and methods eggplant fruits of “tunisina”, “buia” and “l 305” genotypes belonging, respectively, to the “round, violetta pale-purple”, “oval, deep purpleblack” and “long, deep purple” typologies were harvested at the commercial ripening stage in the experimental field of cra-orl in montanaso lombardo (lodi, italy). the assayed genotypes differentiate for the peel anthocyanins composition, being the deep purple non-japanese types “buia” and “l 305” characterized by delphinidin-3-rutinoside (d3r; mw 611), while the lighter purple japanese type “tunisina” is characterized by nasunin, a more complex delphinidin-3-(p-coumaroylrutinoside)5-glucoside (mw 920), occurring in cis and trans configuration [6] [21]. selected fruits were randomly divided into three portions and sliced: one portion left untreated (raw), the others employed in grilling and boiling processing, as described by lo scalzo et al. [20]. raw, grilled and boiled samples were lyophilised. the shaken and subsequently centrifuged extracts of 800 mg of eggplant powder with 30 ml of 3% trifluoroacetic acid in meoh were obtained according to ichiyanagi et al. [21] with modifications. cie l*a*b*, chroma* and hue colorimetric coordinates were recorded with a reflectance spectrophotometer (konica minolta spectrophotometer cm-2600d), adapted for a liquid sample. the reflectance spectra of the extracts between 360 and 740 nm with an interval of 10 nm were obtained; the absorbance spectra were calculated according to the following equation: absorbance = log (100/reflectance) a blank consisting of the solvent was also measured, and the corresponding values were subtracted to samples values. moreover, the absorbance spectra in the visible region, the total anthocyanin content and total monomeric anthocyanins were evaluated through the traditional spectrophotometry, with an unicam uv/vis spectrophotometer (1-cm pathlenght cuvette). the whole spectra of extracts, 5-fold diluted with 1% hcl in meoh, were plotted, then the total anthocyanin content (ta) was measured according to the beer-lambert equation, 1. introduction eggplant fruit is known for its high content in phenolic compounds, which are plant secondary metabolites thought to be related to its antioxidant capacity and beneficial effects on human health [1] [2] [3] [4]. phenolic compounds in pulp are mainly represented by chlorogenic acid and other caffeoyl-esters [1], while anthocyanins are the pigments conferring the purple colour of the peel. in the plants, anthocyanins display a wide range of structures, due to different hydroxyl and methoxyl groups, glycosylation and acylation of the aglycone moieties. thus, the chemical composition along with the medium conditions differently affected the colour and stability of anthocyanins. eggplant anthocyanins have simple profiles generally characterized by a single delphinidin-glycoside [5] [6]. delphinidin is the most hydroxylated and one of the most unstable, as the increasing hydroxylation on the b-ring shifts to longer wavelenghts its maximum visible absorption, nevertheless destabilizing the molecule [5] [7]. in particular, the ortodiphenolic structure increases the total antioxidant activity [8] [9] [10], but makes the molecule a better substrate for polyphenol oxidase [11] [12] [13]. anthocyanins are also known to be, unlike other phenolic compounds, deeply affected by heating [14] [15] [16]. it is also reported that techniques involving a partial/mild heating can increase the yield during anthocyanins recovery, due to a protective effect during extraction or a better solubilization [16] or to the inactivation of degradative enzymes [17]. processing and cooking practices can deeply modify physicochemical characteristics of raw vegetables, thus affecting their nutritional quality and antioxidant activity. generally, eggplant fruits have to be cooked before eating, and although total antioxidant capacity and flesh polyphenols can be unaltered or even increased by cooking [18] [19] [20], peel anthocyanin pigments can be reduced [20]. this study reports about the global fate of eggplant pigments after thermal treatment. the modifications on methanolic extracts of raw and cooked fruits of three genotypes assayed with colorimetric and hplc analyses are presented and discussed. 1marta fibiani marta.fibiani@entecra.it 2giuseppe l. rotino giuseppeleonardo.rotino@ entecra.it 2laura toppino laura.toppino@entecra.it 3giuseppe mennella giuseppe.mennella@entecra.it 1roberto lo scalzo roberto.loscalzo@entecra.it 1 cra-iaa, consiglio per la ricerca in agricoltura e l’analisi dell’economia agraria, unità di ricerca per i processi dell’industria agroalimentare 2 cra-orl, consiglio per la ricerca in agricoltura e l’analisi dell’economia agraria, unità di ricerca per l’orticoltura 3 cra-ort, consiglio per la ricerca in agricoltura e l’analisi dell’economia agraria, centro di ricerca per l’orticoltura pigment variation by colorimetric analysis in raw, grilled and boiled eggplant (solanum melongena l.) fruits 4103/15 | cultura e scienza del colore color culture and science using the maximum absorbance (541-543 nm) deducted with the absorbance at 700 nm for haze correction, and using the delphinidin3-glucoside molar absorptivity (ε = 29000) reported in giusti and wrolstad [22]. monomeric anthocyanins (ma) were estimated by a ph-differential method [22], diluting 4-fold the methanolic extracts in aqueous buffers ph 1 and 4.5 and using the cyanidin-3-glucoside absorptivity (ε = 26900). single anthocyanin pigments (sa) present in the extracts, 10-fold diluted with acetic acid, were also assayed by hplc separation, in a jasco system equipped with a inertsil ods3 column (4.6 x 250 mm). the mobile phase consisted of 5% acetonitrile in meoh (solvent a) and 5% acetonitrile in h2o (solvent b). elution was performed at a flow rate of 0.7 ml/min at 40°c by the following linear gradient steps: start condition 10%a-90%b, kept for 5 min, then 75%a-25%b in 25 min, then 10%a-90%b in 5min, kept for 10 min. cisand trans-nasunin (536 nm, rt 16.5 and 17.0 min respectively) and d3r (526 nm, rt 7.8 min) were measured and quantified by comparison to a calibration curve of external standards of purified nasunin and d3r, as described by lo scalzo et al. [20]. anthocyanin contents were expressed in mg/100 g fruit dw. 3. results extracts obtained from the different samples are shown in figure 1. the extracts of non-japanese types “buia” and “l 305”, containing d3r, revealed a much deeper colour both in raw and cooked samples with respect to the japanese type “tunisina”, containing nasunin. as expected, cooked samples differed from raw ones not only for lower intensity but also in hue, being the grilled ones browner. the visual observations well matched with colour coordinates (table 1). in fact, in the raw samples the red component (a*) and colour saturation (c*) values were in the non-japaneses on average twice as high as “tunisina” (2-fold for a*, and 1.8-fold for c*, respectively), while the lighter purple of “tunisina” peel fitted with the slight higher value of extract lightness (l*) with respect to non-japaneses (39.2 vs 35.3 on average). after cooking, the red component and the saturation were depleted, while l* and b* values increased. as summarized by the magnitude of the total colour difference (δe 00 ) between cooked and raw samples, calculated according to ciede2000 equation [23] [24], the boiled samples always had minor variations than grilled ones with respect to raw samples (on average 3.3 vs 7.2), with boiled “tunisina” showing almost no variations (table1). the higher colour intensity in non-japanese types with respect to “tunisina” was kept also in all cooked samples, even if with different proportions. in fact, in grilled samples, a* values of non-japaneses were further increased with respect to “tunisina” (on average 2.7-fold) while c* (including the b* values) was almost the same (on average 1.8-fold), and in boiled samples, due to the little variation of “tunisina”, a* and c* of non-japaneses were less different with respect to “tunisina” (1.5and 1.3-fold, respectively). even if different molar absorptivities in different anthocyanins may occur, the colour intensity exactly reflected the pigment amounts revealed by spectrophotometric and hplc measurements (table 2), thus the data gathered using the three methods were in good agreement with each other. in fact, in raw eggplants the average content of anthocyanin considering the different assays (ta, ma and sa) was 105 mg/100g for “tunisina”, 201 for “buia” and 185 for “l 305”. after grilling, an overall average of only 35% of anthocyanins was recovered, while after boiling the retention was greater (55%). furthermore, “tunisina” anthocyanins always showed a higher stability with respect to non-japanese ones, in agreement with the lower δe00 values obtained (table1). the values of l*, a* and c* colorimetric coordinates were significantly correlated with anthocyanin contents, being a* and c* the highest positively correlated, and l* negatively correlated (table 3). figure 1 raw, grilled and boiled eggplant extracts (3% tfa in meoh) tunisina buia l 305 raw grilled boiled raw grilled boiled raw grilled boiled 42 cultura e scienza del colore color culture and science | 03/15 l* a* b* c* h° δe 00 tunisina raw 39.2 5.2 -2.3 5.7 336.1 . grilled 40.1 1.4 1.9 2.4 54.9 6.1 boiled 39.6 4.2 -2.0 4.7 334.9 1.2 buia raw 35.4 10.7 -2.9 11.1 345.0 . grilled 38.1 4.1 1.6 4.4 21.8 7.8 boiled 37.8 6.0 -1.2 6.1 349.1 5.0 l 305 raw 35.2 9.5 -2.2 9.8 347.0 . grilled 38.2 3.5 1.9 4.0 27.7 7.6 boiled 37.2 6.2 -0.7 6.2 353.4 3.8 ta (spectr) ma (spectr) sa (hplc) mg/100g dw % ret. vs raw mg/100g dw % ret. vs raw mg/100g dw % ret. vs raw tunisina 1 raw 121 . 88 . 107 . grilled 51 42 41 47 37 35 boiled 87 72 72 81 70 66 buia 2 raw 231 . 158 . 214 . grilled 80 35 60 38 52 24 boiled 100 43 73 46 79 37 l 305 2 raw 207 . 146 . 202 . grilled 77 37 52 36 46 23 boiled 120 58 76 52 91 45 table 1 colorimetric coordinates of eggplant extracts. δe00 = total colour difference of cooked vs raw samples. table 2 total (ta) and monomeric (ma) anthocyanin content measured by spectrophotometric assays, and single anthocyanins (sa) by hplc assay (see text); anthocyanin retention percentage of cooked vs raw samples. 1 nasunin; 2 d3r figure 2 – comparison of absorbance spectra of eggplant extracts obtained by reflectance spectrophotometry and uv/vis spectrophotometry (see text). in the x-axis the wavelenght (350750nm); in the y-axis the absorbance arbitrary units. purple line: raw eggplant; brown line: grilled eggplant; pink line: boiled eggplant. table 3 correlation indices between colorimetric coordinates and anthocyanin contents. * : p<0.0025; ** : p< 0.001; *** : p< 0.0005 l* a* b* c* h° ta -0.884 ** 0.974 *** -0.749 0.987 *** 0.615 ma -0.846 * 0.961 *** -0.782 0.978 *** 0.629 sa -0.848 * 0.954 *** -0.769 0.973 *** 0.630 0,0 0,1 0,2 0,3 350 450 550 650 750 tunisina reflectance spectrophotometry 0,0 0,1 0,2 0,3 350 450 550 650 750 buia 0,0 0,1 0,2 0,3 350 450 550 650 750 l 305 0,0 0,2 0,4 0,6 0,8 350 450 550 650 750 uv/vis spectrophotometry 0,0 0,2 0,4 0,6 0,8 350 450 550 650 750 0,0 0,2 0,4 0,6 0,8 350 450 550 650 750 4303/15 | cultura e scienza del colore color culture and science the variations in visible spectrum were not limited to the anthocyanins region (around 540 nm) but involved all the other regions as well (figure 2). reflectance and absorbance spectra generally well matched all over the visible region, describing the same trends in raw and cooked eggplants extracts. the raw non-japanese types showed two distinct additional peaks, at 420 and 650 nm, identifiable in both spectra types, while a third minor peak or shoulder, nearly at 400 nm, was just evident only in absorbance spectra (original scans, not shown). these additional peaks were less influenced by cooking with respect to those of the anthocyanins, being little the optical density variations at 400 and 420 nm both in reflectance and in absorbance spectroscopy (on average 104 % for grilled samples, and 96 % for boiled ones). a further extraction with n-hexane revealed, in absorbance spectroscopy, the almost complete disappearance of these peaks in the hydrophylic fraction (data not shown), giving the chance to state that these compounds have a lipophylic nature, hence related to other pigments instead of phenolics. in reflectance spectrophotometry the japanese type “tunisina”, showing no additional peaks, nevertheless showed a marked increase in optical density at 370-490 nm after grilling with respect to raw and boiled samples. 4. discussion and conclusions anthocyanin quantifications carried out by spectrophotometry and by hplc separation were in good agreement. unlike other phenolic compounds such as caffeic acid derivatives, eggplant anthocyanins were strongly depleted after cooking, being boiling (a mild heating process) more preservative than grilling. nasunin, the anthocyanin detected in “tunisina”, was in percentage more retained than nonjapanese anthocyanin d3r, particularly in boiling process. total anthocyanin content (ta) of methanolic extracts gave an overestimation with respect to monomeric anthocyanins (ma) and single anthocyanins (sa) by hplc analysis. these differences were greater in cooked samples (tab.2), because copigmentation and formation of new compounds may occur after cooking [5]. colorimetric coordinates well monitored colour modifications due to anthocyanins depletion, showing a decrease of a* value and an increase of b* value after cooking: this is in agreement with the loss of the delphinidin-related redblue colour. in fact, the total colour difference δe00 was highly correlated with the retention of anthocyanins after cooking (r = -0.982, p<0.0005). thermal treatments caused a strong depletion of the eggplant anthocyanins. it is known that the stability of anthocyanins is influenced by its total amount and the simultaneous presence of different types of anthocyanins. in particular, hayashi et al. [14], investigating a number of vegetable and fruit, evidenced the positive relationship between the colour stability of anthocyanins subjected to heating and the number and acylation of anthocyanins. eggplant, having a very simple anthocyanin profile characterized by a single anthocyanin, was one of the most unstable. our results were in accordance to hayashi et al. [14] findings, also with regards to the acylated anthocyanin nasunin, which was more stable than d3r, its non-acylated derivative. lipophylic compounds observed at 400420 nm in non-japanese types showed a better resistance to thermal treatments than anthocyanins, this indicates that they could belong to carotenoids and other pigments, whose presence in eggplant fruits has been previously reported [25] [26] [27]. grilled “tunisina” had the lowest anthocyanin loss with respect to grilled “buia” and “l 305”, but the highest percentage loss of a* value with a marked increase in optical density at 370-490 nm. probably, a* value is positively correlated to anthocyanin and also to other pigments such as melanoidins which are affected by heating. therefore, the browning process consequent to grilling seems different from enzymatic or nonenzimatic browning of pulp and juices, that is generally associated to an increase of a* value and to a loss of lightness [28]. in conclusion, colorimetric and hplc analysis of methanolic eggplant extracts were equally suitable to describe the global fate of fruit eggplant pigments after thermal treatments. bibliography [1] singh a.p., luthria d., wilson t., vorsa n., singh v., banuelos g.s., pasakdee s. polyphenols content and antioxidant capacity of eggplant pulp. food chem. 2009, 114: 955-961. [2] hanson p.m., yang r., tsou s.c.s., ledesma d., engle l., lee t. diversity in eggplant (solanum melongena) for superoxide scavenging activity, total phenolics, and ascorbic acid. j. food comp. anal. 2006, 19: 594-600. [3] matsubara k., kaneyuki t., miyake t., mori m. antiangiogenic activity of nasunin, an antioxidant anthocyanin, in eggplant peels. j. agric. food chem. 2005, 53: 6272-6275. [4] noda y., kaneyuki t., igarashi k., mori a., packer l. antioxidant activity of nasunin, an anthocyanin in eggplant peels. toxicology 2000, 148: 119-123. 44 cultura e scienza del colore color culture and science | 03/15 [5] mazza g., miniati e. anthocyanins in fruits, vegetables, and grains, crc press inc., boca raton, fl, 1993. [6] azuma k., ohyama a., ippoushi k., ichianagi t., takeuchi a., saito t., fukuoka h. structures and antioxidant activity of anthocyanins in many accessions of eggplant and its related species. j. agric. food chem. 2008, 56: 1015410159. [7] ioncheva n., tanchev s. kinetics of thermal degradation of some anthocyanidin-3,5-diglucosides. z. lebensm. unters. forsch. 1974, 155: 257-262. [8] rice-evans c.a., miller n.j., paganga g. structureantioxidant relationships of flavonoids and phenolic acids. free radic. biol. med. 1996, 20: 933-956. [9] wang h., cao g., prior r.l. oxygen radical absorbing capacity of anthocyanins. j. agric. food chem. 1997, 45: 304-309. [10] thavasi v., leong l.p., bettens r.p.a. investigation of the influence of hydroxy groups on the radical scavenging ability of polyphenols. j. phys. chem. a 2006, 110: 49184923. [11] sakamura s., obata y. anthocyanase and anthocyanins occurring in eggplant, solanum melongena l. (i). agr. biol. chem. 1961, 25: 750-756. [12] sakamura s., watanabe s., obata y. anthocyanase and anthocyanins occurring in eggplant, solanum melongena l. (iii). oxidative decolorization of the anthocyanin by polyphenol oxidase. agr. biol. chem. 1965, 29: 181-190. [13] pérez-gilabert m., garcía carmona f. characterization of catecholase and cresolase activities of eggplant polyphenol oxidase. j. agric. food chem. 2000, 48: 695700. [14] hayashi k., ohara n., tsukui a. stability of anthocyanins in various vegetables and fruits. food sci. technol., int. 1996, 2: 30-33. [15] havlíková l., míková k. heat stability of anthocyanins. z. lebensm. unters. forsch. 1985, 181: 427-432. [16] cacace j.e., mazza g. optimization of extraction of anthocyanins from black currants with aqueous ethanol. j. food sci. 2003, 68: 240-248. [17] brambilla a., lo scalzo r., bertolo g., torreggiani d. steam-blanched highbush blueberry (vaccinium corymbosum l.) juice: phenolic profile and antioxidant capacity in relation to cultivar selection. j. agric. food chem. 2008, 56: 2643-2648. [18] yamaguchi t., mizobuchi t., kajikawa r., kawashima h., miyabe f., terao j., takamura h., matoba t. radicalscavenging activity of vegetables and the effect of cooking on their activity. food sci. technol. res. 2001, 7: 250-257. [19]jiménez-monreal a.m., garcía-diz l., martínez-tomé m., mariscal m., murcia m.a. influence of cooking methods on antioxidant activity of vegetables. j. food sci. 2009, 74: h97-h103. [20]lo scalzo r., fibiani m., mennella g., rotino g.l., dal sasso m., culici m., spallino a., braga p.c. thermal treatments of eggplant (solanum melongena l.) increases the antioxidant content and the inhibitory effect on human neutrophil burst. j. agric. food chem. 2010, 58: 33713379. [21] ichiyanagi t., kashiwada y., shida y., ikeshiro y., kaneyuki t., konishi t. nasunin from eggplant consists of cis-trans isomers of delphinidin 3-[4-(p-coumaroyl)-lrhamnosyl (1-6)glucopyranoside]-5-glucopyranoside. j. agric. food chem. 2005, 53: 9472-9477. [22] giusti m.m., wrolstad r.e. characterization and measurement of anthocyanins by uv-visible spectroscopy. eds.: wrolstad r.e., acree t.e., decker e.a., penner m.h., reid d.s., schwartz s.j., shoemaker c.f., smith d.m., sporns p. in: current protocols in food analytical chemistry. hoboken, nj, usa: wiley & sons, inc; 2001. p f 1.2.1-f 1.2.13 [23] cie. improvement to industrial colour-difference evaluation. vienna: cie publication no. 142-2001, central bureau of the cie, 2001. [24] www.brucelindbloom.com [25] aruna g., mamatha b.s., baskaran v. lutein content of selected indian vegetables and vegetables oils determined by hplc. j. food comp. anal. 2009, 22: 632-636. [26] el-qudah j.m. identification and quantification of major carotenoids in some vegetables. am. j. applied sci. 2009, 6: 492-497. [27] yoshikawa k., inagaki k., terashita t., shishiyama j., kuo s., shankel d.m. antimutagenic activity of extracts from japanese eggplant. mut. res. 1996, 371: 65-71. [28] zuo l., seog e.j., lee j.h. effects of ascorbic and citric acids on cie color values of fresh-cut apples cubes. j. food tech. 2008, 6: 20-24. cultura e scienza del colore color culture and science 5103/15 | cultura e scienza del colore color culture and science order of its texts. this study aims to thoroughly investigate this section of the clt. 2. recipes of de coloribus the sequence of forty texts in the de coloribus may be divided into three sections according to the specific colour pigments described. the product may be obtained using both vegetal and animal substances. in the end, the text informs us about the application on different supports (figure 1). the first eight texts describe the preparation of azure pigments and recommends several ingredients: violets, lilies, chelidoniums, and woads. the dosages of flowers and leaves are indicated, as well as how to work them to prepare their pulps for the extraction of dyes. additional ingredients are also required for different hues and de coloribus lists verdigris, cinnabar, saffron, vitriol, white lead, and lime. the latter is probably obtained following the traditional calcination of oyster shell. the reds of de coloribus are made up of two different compounds. one consists of vegetal ingredients added to mixtures of cinnabar or white lead. the other one uses animal ingredients such as the insect kermes, here named coccarin or vermiculus, enriched with cinnabar and white lead. in a third section, several recipes refer to the preparations for various hues of pandius, which may refers to any mixture made from the combination of several ingredients, the interpretation of which is for the most still unknown to scholars. de coloribus lists at least the following ingredients and the quantity needed according to each combination: lulacin, cinnabar, white lead, ficarim, ochre, burnt copper, quianus, reseda luteola, saffron, terra verde, murices decoction, siricum, kermes decoction, madder decotion, phynicis decoction, galls, calcitarin, and so on. a final text that might have served as an explicit completes the sequence for pigment making. it provides further indications as to their application on various supports, informing us about the measurements necessary to ensure a good result. de coloribus advises that the pigments should be used directly on the wall, but in other cases the product needs to be mixed with wax for wood painting or isinglass for skins supports. 1. introduction this study analyses written records on the making of pigments in europe since the 8th century and contained in heterogeneous collections. the focal point of the paper is a series of about forty texts on pigment making for wall painting that i have conventionally termed de coloribus. it forms a large section of a recipe book on practical arts known as compositiones lucenses, which is the first western example of literature on artistic and architectural procedures that has ever survived. this collection was compiled between antiquity and late antiquity, collecting various sources, in part still fluid and unidentified [1]. the first specimen hails from the beginning of carolingian times. this is the well-known manuscript 490 held at the biblioteca capitolare of lucca, dated between 796 or 787-816 ad [2]. it comprises 160 titles for buildings foundations, military machines and incendiary mixtures, metal works, glass and skins colourings, dyes, pigments for wall application, descriptions and uses of stones, metal inks for writing, and parchment dyeing. unlike other ancient and medieval sources, irretrievably lost or not reproduced in a literary diffusion, this recipe book extends beyond carolingian times and endures in a tradition consisting of several other manuscripts, which can be collectively termed the ‘compositiones lucenses tradition’ (hereafter clt). current research indicates that the entire recipe book was transmitted by at least twentysix manuscripts, most of which represent recent acquisitions. nevertheless, its contents are seemingly continually changing and subject to reformulations and contaminations. in the subsequent examples, the recipe book exceeds 200 titles, with additions being made since the 9th century. an editio minor, i.e. a specific nucleus of recipes from the compositiones lucenses tradition, has also been circulated and systematically copied in the medieval manuscripts of vitruvius’ de architectura, which is the most important work on practical arts and architecture from antiquity [3]. on the basis of new evidence, the section de coloribus on pigments making stands out as one of the most significant parts of the clt, even though it was copied with much alterations and reshaping, both to its general contents and to the giulia brun giulia.brun@gmail.com dastu department politecnico di milano de coloribus: new perspectives on a series of recipes for making pigments within the compositiones lucenses tradition 52 cultura e scienza del colore color culture and science | 03/15 recipes of de coloribus, from: città del vaticano, biblioteca apostolica vaticana, reg. lat. 2079, ff. 77r-79v 1. compositio lulaci caucallide flore lini in mundi mamma viole duarum duarum supradicta 2. flores neulacis quod grece tapsya dicitur alii camaleunta collige flores et repone et post hec 3. lazurin diforon qui dicitur bifaces flores neulacis comisce cum urina expumata secundum 4. lazurin melini zonta flores neulacis infunde in aceto et compone in vase sicut primum 5. lazurin arinon tolles florem de nealuce et defricas cum sapone sicut superius docuimus 6. lazurin carnei coloris tolle lazurin ÷ i cinnabarin libram unam phymithim libram 7. lazurin hunici zonta tolle psimithin mundum et tritum libram unam lazurin ÷ i 8. lazurin ethizonta tolle neulacis flores unctum ex sapone sicut superius lib. i et pone 9. luseum vero de tribus spetiebus componitur hec concoquitur sic tolle lacca teres utiliter et 10. compositio alithini flores papaveris tribula et exprime et humorem qui exierit ÷ i cinnabarin 11. a(lia) cinnabarin ÷ i lulacis sol ii psimithin sol i trita bene repone ad solem 12. alia compositio vermiculi libras iii vermiculi terreni qui in folia cedri nascitur libram unam 13. alia compositio vermiculi mitte vermiculi libram unam coccarin libram i coccarin nascitur 14. item alia compositio vermiculi vermiculi libram dimidiam alius vermiculi ÷ vi lulaci ÷ vi 15. de pandio lulacin pandium luracin libras duas cinnabarin libram unam psimithin 16. aliud pandium lulacim libras ii cinnabarin vero principalis lib. i lazurin lib. i 17. alia compositio lulacin ÷ iii psimithin ÷ viiii 18. item alia compositio lulacin ÷ i ficarin ÷ i quianus ÷ i pandius lib. psimithin lib. i 19. alius pandius quianus lib. i ocrea lib. ii omnia trita comisce cum urina expumata 20. item alius pandius quianus lib. i calcuce caume tritum pulverem ÷ i ficarin ÷ ocrea ÷ i 21. primus pandius cinnabarin coloris cinnabarin lib. i herbe luzie coctionem lib. i croco claro 22. pandius cinnabarin coloris cinnabarin ÷ vi lacca autem decoctioni iotta crocum et vi 23. pandius cinnabarin ÷ i incausta spetiarum tritum ÷ i tereris commisce et reponens in vase vitreo 24. pandia vocantur omnes colores pandius cinnabarin ÷ i et sta teres bene in mortario et 25. pandius viridis terra viride ÷ ii cinnabarin ÷ ii terra commisce ac repone quem ad modum 26. item pandius viridis terra viride lib. i cinnabarin ÷ i psimithin sol ii ista teres in mortario 27. item pandius viridis terra viride lib. i ocrea ÷ i cinnabarin ÷ i trita et commixta omnia cum 28. pandius ocrei coloris ocrea munda lib. i cinnabarin z i ficarin sol. iii omnia trita in 29. pandius purpurei coloris pandius purpurei coloris compositus ex iiii speciebus lulacin lacca 30. pandius porfyrius iocta decoctionis conchilii lib. i cinnabarin ÷ i siricum mundum ÷ i omnia 31. pandius porphyrus iotta conchilii libra i cinnabarin lib. ii crocum ÷ ii omnia trita commisce 32. pandius porphyrus iotta conchilii cinnabalin ÷ i iotta de lacca et terens primum cinnabatin et 33. pandius sub porphyrus iota conchilii ÷ i cinnabarin ÷ i crocum ÷ i iotta herbe lucie ÷ iiii 34. pandius cynnabarin ÷ i iotta conchilii ÷ i coctio rubie ÷ ii coctionem phinicis teres primum 35. pandius tolle ius rubie et addis galle ÷ iii et teres utiliter et tolle ex iotta rubie ii et mitte in vase 36. quianus nascitur de rosa baltasion nascitur enim in locis humidis nascitur quidem ex rosa estivo 37. quianus nascitur sic propter pensum ante commixtionem spetierum marmorem tritum bene 38. pandius viridis quianus viridis lib. i psimithim ÷ i ista commisce cum urina expumata 39. pandius quianus lib. i cinnabarin ÷ i trita cum urina expumata 40. hec omnia exposuimus quamquam ex terrenis maritimis floribus vel herbis exposuimus virtutes the majority of the recipes have a distinct paratactic structure that sets out all the directions for producing pigments. ingredients, quantities and instructions are for the most part simply listed, omitting any redundant information. this approach was distinctive of the medieval man and reflects a typical expedient used to meet the interests of a readers’ community to which, ideally, a recipe book should have been addressed. recipes appear to have been an extraordinary vehicle for communicating a practical and useful function, which is almost always stated, although we cannot assume medieval readers always pursued it. at the same time, these written records seem to document only a restricted and limited segment of the practical know-how. many ingredients are still difficult to identify and the technical progression of practical instructions seems to be overshadowed by an extensive use of crossreferences. formulas such as sicut superius diximus, sicut superius dictum est, or sicut supra are recurring linguistic features employed by scribes to replace superfluous or unnecessary information. 3. the clt manuscripts containing de coloribus the most ancient example of de coloribus is the just mentioned lucca manuscript (lucca, biblioteca capitolare, 490). according to scholars, it was written in the lucca scriptorium at the turn of the 9th century. this is evident by the use of a lucchese script, the presence of texts written by lucca’s bishop himself, and the contents that chronologically list the compilation between 787 (or 796) and 816 ad [4]. just after the lucca manuscript, another witness was copied at the beginning of 9th century and discovered by the librarian of the augustine library in klosterneuburg (klosterneuburg, stiftsbibliothek, frag. s.n.) [5]. the codex has been seriously damaged and only four parchment folios, in two quires, have survived. nevertheless, previous studies have assumed that the original collection might have been constituted by at least 119 recipes, given that the second-last recipe is numbered cxviii [6]. a subsequent proposition comes from a 10th century manuscript from the sélestat library, known to scholars for being a good witness of several texts related to architecture and art, such as vitruvius’ de architectura, cetius faventinus’ de diversis fabricis architectonicae, and a collection of alchemical-metallurgic matter entitled mappae clavicula (sélestat, bibliothèque humaniste, 17) [7; 8]. in the 12th century, the clt counts on two manuscripts. the first is the most notorious witness of mappae clavicula, edited in 1847 by its former possessor sir thomas phillipps and now preserved in the corning museum of glass (corning, museum of glass, phillipps 3175) [9; 10]. it comprises three works: a recipe book for illuminators known as de coloribus et mixtionibus, the alchemical collection on metals mappae clavicula, and the clt with significant linguistic modifications and textual additions [11; 12]. almost coeval to the corning copy, a vitruvian manuscript formerly owned by the queen christina of sweden is now conserved at the vatican library (città del vaticano, biblioteca apostolica vaticana, reg. lat. 2079) [13]. it is believed that this specimen is one of the most complete and linguistically best witnesses of the clt [14]. the 13th century is rich in further examples. two english manuscripts embed the clt with figure 1 recipes of de coloribus, from: città del vaticano, biblioteca apostolica vaticana, reg. lat. 2079, ff.77r-79v 5303/15 | cultura e scienza del colore color culture and science alchemical texts, including mappae clavicula. one has undoubtedly been compiled in the saint augustine monastery in canterbury and was donated to the bodleian library in 1612 (oxford, bodleian library, bodley 679). the other was given to the bodleian library in 1634, but was previously in sir kenelm dibgy’s collection (oxford, bodleian library, digby 162) [15]. another 13th century manuscript has probably italian origins, given that a piece of paper with italian writings has been used for its binding. however, the interruption of the transcription on f. 100v suggests that it might have been dismembered (london, british library, add. 41486). in italy, two clt manuscripts were copied in the 14th century. the first is a parisian codex that belongs to a group of codices transmitting the same florilegium (paris, bibliothèque national de france, lat. 7418), although it seems that this is the only witness of the same family that holds de coloribus. the other example is a manuscript written in southern italy in which the clt forms a seamless nucleus with mappae clavicula and the treatise de diversis artibus by the monk theophilus (firenze, biblioteca nazionale centrale, pal. 951) [16]. three further manuscripts – one dated to the 14th century and two to the 17th century – have been recognised as descripti, i.e. direct copies from previous examples that provide corroborating evidence as to the circulation of the clt, which was much wider than initially thought (glasgow, university library, hunterian 110; leiden, rijksuniversiteit bibliothek, vfc 33; siena, biblioteca degli intronati, c.v.24). the contents of the overall collection of the clt consisting of twenty-six manuscripts are extremely heterogeneous: each individual manuscript seems to represent a different arrangement, depending on the texts availability or personal interest of the scribe. to the best of our knowledge, thirteen manuscripts each contain one or more text-units from de coloribus. the data generated by the analysis of the global contents of the clt, reported in a provided diagram (figure 2), shows that the section de coloribus devoted to pigment making constitutes a highly significant percentage of each arrangement, which seems to confirm the value attributed to them by previous collectors who selected these recipes rather than others. in the diagram, each blue line shows the extent of titles from de coloribus compared to the remaining texts of the clt. the amounts are expressed in percentages to prevent distortions that might be due to the specific features of each manuscript. the actual volume of the sequence inside the clt is shown. the results indicate that the klosteneuburg manuscript, although fragmentary, is made up of nearly 40% of recipes from de coloribus. the majority of witnesses range between 10-20%, but the oxonienses bodley 679 surpasses that 20% compared to its global contents of the clt. on the contrary, the five remaining manuscripts are all under 10%. 4. de coloribus: contents and ordering it is distinctive that each witness of de coloribus transcribes a unique amount of texts displayed in a peculiar order. indeed, care must be taken in basing the comparison solely on the most ancient manuscript and we ought to consider instead that earliest manuscripts are not necessarily the most reliable. in fact, the data reveals that the arrangement in the most ancient lucca manuscript is apparently overturned and suggests that the vatican manuscript might contain the best textual example of this. a provided graphic (figure 3) attempts to verify that the sequence of text-units, i.e. consecutio, 0%   10%   20%   30%   40%   50%   60%   70%   80%   90%   100%   london, british library, harley 2767 [h] london, british library, add. 41486 [l] oxford, bodleian library, bodley 679 [ob] oxford, bodleian library, rawlinson d893 [or] oxford, bodleian library, digby 162 [od] oxford, magdalen college, 173 [om] glasgow, university library, hunterian 110 [g] sélestat, bibliothèque humaniste, 17 [s] paris, bibliothèque national de france, lat. 7418 [p] paris, bibliothèque national de france, lat. 6514 [pa] paris, bibliothèque national de france, lat. 6830f [pb] paris, bibliothèque national de france, lat. 11212 [pc] klosterneuburg, stiftsbibliothek, frag. s.n. [k] città del vaticano, biblioteca apostolica vaticana, reg. lat. 2079 [v] città del vaticano, biblioteca apostolica vaticana, pal. lat. 1449 [vp] leiden, rijksuniversiteit bibliothek, vfl 88 [ll] leiden, rijksuniversiteit bibliothek, vfc 33 [lc] madrid, real biblioteca de escorial, iii.f.19 [e] madrid, biblioteca nacional, 19 [m] corning, museum of glass, phillipps 3175 [c] new york, metropolitan museum of art, dept. of prints, pl.1 [n] lucca, biblioteca capitolare, 490 [lu] firenze, biblioteca medicea laurenziana, pl. xxx.10 [f] firenze, biblioteca nazionale centrale, pal. 951 [fp] firenze, biblioteca nazionale centrale, pal. 981 [fc] siena, biblioteca degli intronati, c.v.24 [si] percentage of de coloribus titles compared to overall contents of compositiones lucenses tradition (clt) according to the manuscripts de coloribus titles clt titles figure 2 percentage of de coloribus titles compared to overall contents of compositiones lucenses tradition (clt) according to the manuscripts 54 cultura e scienza del colore color culture and science | 03/15 0   50   100   150   200   250   0   1   2   3   4   5   6   7   8   9   10  11  12  13  14  15  16  17  18  19  20  21  22  23  24  25  26  27  28  29  30  31  32  33  34  35  36  37  38  39  40  c or re sp on de nc es a nd c on se cu tio in s el ec te d m an us cr ip ts [s ; k ; c ; l u; f p] text-units consecutio in città del vaticano, biblioteca apostolica, reg. lat. 2079 [v] de coloribus: text-units correspondences and spearman’s rank-order correlation coefficient (ρ) sélestat, bibliothèque humaniste, 17 [s] klosterneuburg, stiftsbibliothek, fragm. s.n. [k] corning, museum of glass, phillipps 3715 [c] lucca, biblioteca capitolare, 490 [lu] firenze, biblioteca nazionale centrale, pal. 951 [fp] ρ [s] = 1 ρ [c] = 0.99 ρ [lu] = – 0.5 ρ [fp] = 0.42 ρ [k] = 0.99 figure 3 de coloribus: text-units correspondences and spearman’s rank-order correlation coefficient (ρ) has been severely altered in some manuscripts of the same clt such as the lucca manuscript, which does not seem to be reliable in the study of this literature. the diagram pictures the consecutio of six selected manuscripts of de coloribus. the x-axis registers the sequence of the vatican manuscript reg. lat. 2079, designated as the role model. the y-axis records the consecutio of five witnesses chosen for the comparison. each point of the diagram represents the ordinal position of a given recipe in both the vatican and the matched example. for instance, every triangle has two coordinates, one for corning numbering and another for the vatican’s de coloribus. as a result, sélestat and corning manuscripts contain collectively 39 out of the 40 text-units and only one recipe has not been transmitted. the 9th century klosterneuburg manuscript contains merely 15 recipes, although orderly copied. by contrast, both the lucca and florence examples provide a disjoined sequence, visibly incomplete and unordered. the distances between the points graphically indicate that several recipes of vatican’s de coloribus are absent in the two italian witnesses. on these grounds, we would expect that some manuscripts were much more related than others and that the lucca manuscript was the most altered. a further analysis on the consecutio given by the thirteen witnesses of de coloribus lead to one crucial question that this section attempts to answer: is it possible to determine the hypothetical and most extensive sequence accountable for the effective ordering provided by the majority of manuscripts? given the centrality of the issue for the present aims, it seems fair to suggest applying the spearman’s rank correlation coefficient, i.e. a nonparametric indicator of correlation (ρ) to statistically measure the connection between two ordinal variables as the consecutio of textunits given by two manuscripts. the results are shown in the diagram together with the correspondences of recipes between vatican’s de coloribus and five other manuscripts. a perfect correlation occurs when spearman’s coefficient is +1 since the variables are arranged consecutively identical, or consecutively specular when -1. when applied to the vatican-sélestat pair spearman’s measure calculates a +1 value, meaning that the manuscripts are strongly correlated because the first unit in both vatican’s and sélestat’s de coloribus exactly matches, and similarly for the rest of the sequence. however, spearman’s coefficient only determines the correlation between pairs of variables, i.e. equal text-units from two manuscripts. if there is not a recipe in just one of the two arrangements, the statistical dependence cannot be calculated. this deficiency, however, has not modified the sequence structure and the rate of relationship. for instance, recipe no. 31 in vatican’s de coloribus has no correspondence with any textunit of the sélestat manuscript, and therefore the correlation is calculated on 39 pairs of texts, but still equals a +1. as a result, the spearman’s correlation coefficient resists the elimination of one or more units and can be positively applied even on the lucca manuscript. in the latter, however, the value is -0.5: a negative coefficient which indicates only a modest inverse correlation with vatican’s sequence. the high ranks of correlation between the vatican manuscript and the sélestat-corning consecutio can be further rationalised. i exclude the possibility that any of these manuscripts is a descriptus, i.e. a direct copy, because it appears more reasonable that they are all related to the same literary material. on logical grounds, i suggest that the three manuscripts have simply maintained the same sequence of recipes during 5503/15 | cultura e scienza del colore color culture and science the copying process. in stark contrast, the lucca and florence manuscripts have intercepted the same written flow of de coloribus, but have both partially transcribed it. moreover, the lucca sequence presents an inverse tendency, but at the time the cause behind this consecutio distortion remains a speculation. 5. conclusions de coloribus is the most ancient sequence devoted to pigment making transmitted from antiquity to the middle ages. it constitutes a large part of recipes in many clt manuscripts that individually contain a unique arrangement of texts. this study has shown that thirteen clt manuscripts contain de coloribus and has documented its exact extension of forty recipes into three sections individually devoted to azure, red, and pandius pigments, with concluding instructions on their application. the diagrams clarify the relationships between witnesses and point out additional crucial factors. on the one hand, it has been verified that the lucca specimen is evidently not an accurate and reliable source. instead, the study of the vatican manuscript has been suggested as the role model for this sequence. moreover, the degree of correlation between six selected manuscripts has been demonstrated confirming that unlike other examples, lucca’s de coloribus is not only incomplete but inversely transmitted. even though the historical literary sources on crafts and artisan knowledge have roots in antiquity, compositiones lucenses is the first case in which literary sources on art productions appeared in europe and recipes and written records represent themselves as artefacts and cultural products that deserve to be studied for their intrinsic features. this paper has provided a new perspective of this first ensemble of painting pigments named de coloribus, which paved the way for the subsequent emergence of new written evidence on craft experience that from the 14th century focused exclusively on the production of pigments. acknowledgements i would like to acknowledge dr guido frison for introducing me to the topic of spearman’s correlation measure and for reading the manuscript at various stages. bibliography [1] r. p. johnson, compositiones variae from codex 490, biblioteca capitolare, lucca, italy. an introductory study, «illinois studies in language and literature», 23, 3, urbana 1939. [2] l. a. muratori, antiquitates italicae medii ævi, ii, milano 1739. [3] the medieval tradition of compositiones lucenses and its connection to vitruvius’ manuscripts has been at the centre of the phd dissertation of the undersigned: g. brun, the transmission and circulation of practical knowledge on art and architecture in the middle ages. the case of compositiones lucenses tradition and its connection to vitruvius’ de architectura, phd dissertation, politecnico di milano, 2015. [4] l. schiaparelli, il codice 490 della biblioteca capitolare di lucca e la scuola scrittoria lucchese, sec. 8.-9.: contributi allo studio della minuscola precarolina in italia, roma 1924. [5] w. ganzenmüller, ein unbekanntes bruchstück des mappae clavicula aus dem anfang des 9. jahrhunderts, «mitteilungen zur geschichte der medizin, der naturwissenschaften und der technik», 40, 1941, pp. 1-15. [6] w. ganzenmüller, beiträge zur geschichte der technologie und der alchemie, weinheim-bergstraße 1956. [7] a. giry, note sur un manuscrit de la bibliothèque de sélestat, «revue de philologie, de littérature, et d’histoire anciennes», 3, 1879, pp. 16-18. [8] the manuscripts of mappae clavicula, which for the most contain also excerpts from the clt, has been recently studied by the undersigned and published inside the first critical edition of the text edited by sandro baroni, giuseppe pizzigoni, and paola travaglio. g. brun, i codici testimoni di mappae clavicula, in s. baroni, g. pizzigoni, p. travaglio (eds.), mappae clavicula. alle origini dell’alchimia in occidente. testo, traduzione, note, saonara 2014, pp. 201-217. [9] t. phillipps, letter from sir thomas phillipps addressed to albert way communicating a transcript of a ms treatise on the preparation of pigments, and on various processes of the decorative arts practiced in the middle ages, written in the twelfth century, and entitled mappae clavicula, «archaeologia, or miscellaneous tracts relating to antiquity», 32, london 1847, pp. 183-244. [10] c. s. smith, j. g. hawthorne, mappae clavicula: a little key to the world of medieval techniques, «transactions of the american philosophical society», 64, 4, 1974, pp. 1-128 [11] d. v. thompson, artificial vermilion in the middle ages, «technical studies», ii, 1933, pp. 62-70. [12] a. petzold, de coloribus et mixtionibus: the earliest manuscripts of a romanesque illuminator’s handbook, in l. l. brownrigg (ed.), making the medieval book: techniques of production. proceedings of the fourth conference of the seminar in the history of the book to 1550 (oxford, july 1992), london 1995, pp. 59-64. [13] g. brun, de emplastro. prime considerazioni su un inedito trattatello di pittura murale altomedievale, «acme», vol. lxiv, iii, 2011, pp. 51-74. [14] f. tolaini,’de tinctio omnium musivorum’. technical recipes on glass in the so-called ‘mappae clavicula’, in m. beretta (ed.), when glass matters, firenze 2004, pp. 195-214. [15] f. madan, h. h. e. craster, a summary catalogue of western manuscripts in the bodleian library at oxford, 4 vols, oxford 1922. [16] g. pomaro, i ricettari del fondo palatino della biblioteca nazionale centrale di firenze: inventario, milano-firenze 1991. cultura e scienza del colore color culture and science 4304/15 | cultura e scienza del colore color culture and science 1,3 arvi tavast arvi@tavast.ee 1,2 mari uusküla muuskyla@tlu.ee 1 dept. of translation studies, school of humanities, tallinn university 2 institute of the estonian language, tallinn 3 dept. of estonian, university of tartu how blue is azzurro? representing probabilistic equivalency of colour terms in a dictionary 1. introduction semasiological dictionaries both store and present information about source language words, including their meanings and targetlanguage equivalents. since this is what dictionary users are consulting a dictionary for, it is the natural way of presenting the dictionary. for compiling and storing dictionary data, however, the solution is less than optimal. the core of the semasiological dictionary data structure is a one-to-many (1:n) relation between words and meanings, i.e. one word can have several meanings, while every meaning has exactly one (source-language) word. in situations of synonymy, information (e.g. definitions and equivalents) must be repeated in each synonym entry, or synonym entries must refer to each other. for both methods or any combinations thereof, semasiological compilation has been shown to cause problems: broken references, synonym conflicts, circularity and inconsistency [1]–[3]. many of these problems can be avoided using the onomasiological approach for compilation, even if published semasiologically. there is still a 1:n relation, but in the opposite direction: one concept can have multiple designations, while each word has exactly one concept it refers to. of the problems listed above, the onomasiological data structure makes broken or circular references and synonym conflicts impossible. it still allows inconsistent information to be entered for similar concepts, though. inconsistencies could only be avoided by systematic terminology work [4], [5]. in terminology, onomasiology is the preferred data structure both in the classical theory [6], [7] and many contemporary approaches [8]–[11]. due to its limited scalability [12], systematic terminology work is less universally recommended, but has still been successfully used in specialised dictionaries [13], [14]. as a more workable alternative, a partially systematic approach has been used for smaller groups of concepts within a dictionary (many dictionaries of the tsk, e.g. [15]). onomasiology is much less known and understood in general lexicography (a notable exception being the wordnet lexical database [16], [17], which is both onomasiological and partially systematic). in what follows, we argue that taking concepts into account is as feasible and beneficial for the compilation of general language dictionaries as it is in terminology. we start by analysing the equivalents in bilingual dictionaries between spanish, italian, english and estonian, finding that dictionary entries are inconsistent, circular and lacking discriminative information. moreover, they also contradict the results of our experiments in castilian spanish [18] and standard italian [19] using the empirical-cognitive field method [20], [21], which we briefly describe in section 4. to conclude, we present extracts from the results of our fieldwork as probabilistic conceptual graphs, representing an n:m relation between words and concepts and encoding the likelihood of a word designating a concept. we propose this data structure as an alternative to the 1:n structures of both semasiology and onomasiology, arguing that it is more robust than the former and more intuitive for the lexicographer than the latter. 2. method of the dictionary study we analysed the dictionary equivalents for the castilian spanish terms violeta, morado and lila designating purplish colours, and the italian terms blu, azzurro and celeste designating bluish colours, which are well known for their lack of direct equivalents in other languages (we purposefully avoid glossing the example terms throughout the article.). the second languages of the bilingual dictionaries were english and estonian. the dictionary sources are listed in [22]. the procedure was the following: 1. look up the headwords in spanish and italian, getting the english and estonian equivalents for each. 2. look up these equivalents in the opposite language direction, getting their back-translations into spanish and italian. 3. present the results as a directed graph of word equivalence relations. 4. weigh the edges of the graph according to the number of dictionaries that contained this particular relation. 44 cultura e scienza del colore color culture and science | 04/15 variation of hyphenation and parentheses was ignored. 3. results of dictionary study figures 1-4 present the results of the dictionary study. estonian dictionary data is more sparse due to the smaller number and volume of dictionaries with this language. dictionaries between english and spanish (figure 1) stand out in terms of having a clear convergence of equivalent pairs across dictionaries. the remaining three language pairs exhibit much more variation. the following can be observed to some degree in all four language pairs: • equivalents tend to follow orthographic similarities across languages. • headword selection is not comprehensive, with even the most frequent colour terms sometimes missing from dictionaries. figure 1 – purplish colours in spanish-english and english-spanish dictionaries figure 2 purplish colours in spanishestonian and estonian-spanish dictionaries • dictionaries of a single language direction contradict each other and do not justify their choice of equivalents, leaving the user with a seemingly random set of equivalent candidates. • dictionaries of two opposite language directions contradict each other. in spanish-estonian dictionaries, the term morado could be either punakasvioletne ‘reddish purple’, tume punakaslilla ‘dark reddish purple’, tumelilla ‘dark purple’ or the estonian basic term lilla ‘purple’. the term violet could be violett, violetne or lilla (the difference between violett/violetne and lilla in estonian could mainly be accounted for through people’s idiolects or individual preferences (see more on estonian purple terms in [23]). the term lila could be (hele)lilla or lilla. each of the three terms was absent from at least one of the dictionaries. according to the dictionaries, all three spanish terms could correspond to the estonian basic term lilla. in estonian-spanish dictionaries the term lilla had also a many different counterparts 4504/15 | cultura e scienza del colore color culture and science (violado, violáceo, de color lila, violeta, lila, morado), without any explanation about the conceptual differences. the terms tend to get counterparts through homography, perhaps neglecting the spectrum that the colour terms represent. we could think that the similar word shape is due to the same etymological background and that assures the counterparts, but languages develop differently and words, though from the same source, develop different meanings through cultural impact [24]. for example, spanish violeta and lila have a very transparent source. however, morado, being a loan from latin mōrum ‘mulberry’ has a very deep cultural meaning. perhaps the cultural importance and a different origin of morado has made the terms for purple divide differently from other languages. 4. method of the fieldwork the field data was obtained using an empiricalcognitive field method following [20], [21]. the method consists of two tasks. in the list task, the figure 3 – bluish colours in italianenglish and english-italian dictionaries figure4 bluish colours in italianestonian and estonian-italian dictionaries participants were asked to name all the colour terms they could think of. in the colour-naming task, 65 matt-surfaced coloured stimuli from the color-aid corporation 220 selection were presented to the participants one by one in a random sequence and they were asked to name the perceived stimuli with the appropriate colour term . 65 stimuli were 5x5 cm plywood squares constituting a “coarse, but evenly spread sample of colour space” ([21]; for seletion criteria see [25]). color-aid is based on ostwald colour system: each colour can be described by cie coordinates available in [25]. the tiles were shown to participants in a random order in natural daylight on a neutral gray surface (comparable to munsell n2). lighting conditions were similar for all participants. the participants were allowed to use simple words, compounds or even phrases. the standard italian data was collected between 2006 and 2008 in florence (102 participants, 56 female, age range 11-80, mean 38.6). the castilian spanish data was collected in 2012 in madrid (38 participants, 20 female, age range 22-85, mean 42.7). participants were all 46 cultura e scienza del colore color culture and science | 04/15 volunteers with different dialectal, educational and occupational backgrounds (for details see [19]). the interviews were carried out in castilian spanish or standard italian by a proficient l2 speaker. estonian data was collected in 2014 (20 participants, 12 female, age range 25-48, mean 31.7). all participants had normal colour vision, as ascertained using either the city university [26] or ishihara’s [27] colour vision tests 5. fieldwork results in the list task, we calculated the naming frequency of a colour term, its mean position in the list and the cognitive salience index which unifies these two parameters [28]. in the colour naming task, we took into account the term frequency, the number of tiles assigned to each colour term, and calculated dominance and specificity indices [20] to examine the consensus rate among the participants [18], [29]. we observe which color-aid tiles the castilian spanish terms for purple and standard italian terms for blue are attached to. spanish morado was given with the highest frequency to tiles vbv (60%) and vrv (58%), violeta to tile vbv-t4 (42%) and lila to tile vrv-s3 (37%). italian blu was most frequently attached to colour tile bvb (named by 54% of participants), while bgb-t3 was regarded as celeste by 57% of respondents. azzurro was used to describe colour tile bgb by 44% of participants. figures 5 and 6 represent extracts from our fieldwork results. the graphs differ from the bilingual graphs of figures 1-4 by the addition of concepts (here represented by codes of colour stimuli) between the languages. edge weights encode the percentage of respondents naming this stimulus with this term and were cut off at 10% (which is why the total of weights for each stimulus is generally less than 100). the graphs contain all stimuli and terms within 3 hops from the original terms, resulting in the inclusion of some terms that intuitively would not belong there. italian verde, for instance, is included among the bluish colours on figure 6 because 10% of estonian respondents called the stimulus bg-s2 sinine ‘blue’ and 24% of the italian respondents called the same stimulus verde. 6. discussion the observed overlaps across categories and shifts across languages illustrate the inadequacy of direct univocal equivalences postulated in dictionaries. colour terms are an exceptionally easy semantic domain to perform such analysis on, due to the relative ease of presenting colour stimuli to participants a similar experiment with modal verbs or abstract nouns would be quite complex if not impossible. however, the same overlaps and shifts are still there regardless of how much is known about the concept, causing the same dangers of misrepresenting linguistic reality in the dictionary. this paper suggests that words should be related to each other only through concepts, since direct relations (synonymy and equivalence) are not flexible enough to figure 5 – purplish colours in spanish and estonian fieldwork results 4704/15 | cultura e scienza del colore color culture and science represent the complexity of natural language. we hope that our solution to using an n:m relation between words and concepts instead of the 1:n of traditional onomasiology will make the approach less daunting to lexicographers by removing the need to have separate headword entries for each meaning of a word. we used probabilistic weighting on our graphs to account for the fact that one meaning of a word can be more likely than another. here the probabilities were obtained from elicited performance experiments, but other sources could be used as well, some of which do not depend on the semantic class, e.g. vector semantics or word-level alignment of parallel corpora. our fieldwork results are consistent with previous studies that underline the special status of blue category in italian (e.g. [19], [30]– [32]). the status of the purple category has been discussed by [34] and [35]. while [35] regard morado and violeta as synonyms, our field data indicates that these colour terms have different conceptual references. our probabilistic conceptual graphs are similar to dyvik’s semantic mirroring [36], [37] and the workflow of the efnilex project [38], [39], differing from them by the explicit addition of concepts into the graph instead of relying on isolation of subgraphs to identify synsets. the objectives of [37] do include obtaining relations between the explicit concepts of wordnet from parallel corpora; what we add is retention of the probability information rather than reducing it to discrete relations. finally, from systematic terminology work ([4], [5]) we differ by the use of probabilities, but also the n:m relations between words and concepts. acknowledgements we are indebted to all our castilian spanish, standard italian and estonian test participants, and to triin kalda who helped to collect the estonian data. notes 1to be precise, concepts are subjective abstractions of indvidually perceived or imagined objects, dependent on a wide range of variables from medical issues to life experience to cultural norms, not the physical objects (colour cards) themselves. the experimental stimuli merely invoke the processes of perception and categorisation, which can then be followed by finding and uttering a name for the resulting concept. the variation in naming includes the variation in perception, and since the experimenter has no access to subjective processes of the participant, these two can not be separated in the current experiment. in any reference to colour (or any other phenomena) in this paper, perception is always implied to be present as an additional degree of freedom. the use of colour tiles as stimuli in this study is only motivated by the fact that there is much less room for variation in the perception of colours compared to the perception of e.g. kindness or running or even bird or table. bibliography [1] a. tavast, “eesti oskussõnastikud 1996-2000,” keel ja kirjandus, vol. 6, 7, pp. 401–414, 489–503, 2002. [2] a. tavast, the translator is human too: a case figure 6 – bluish colours in italian and estonian fieldwork results 48 cultura e scienza del colore color culture and science | 04/15 for instrumentalism in multilingual specialised communication. tartu: tartu ülikooli kirjastus, 2008. [3] a. tavast, “eesti oskussõnastikud 2001–2010,” keel ja kirjandus, vol. 4, pp. 255–276, 2011. [4] s. e. wright and g. budin, handbook of terminology management: application-oriented terminology management. amsterdam: john benjamins, 2001. [5] h. suonuuti, guide to terminology. helsinki: tekniikan sanastokeskus, 2001. [6] e. wüster, einführung in die allgemeine terminologielehre und terminologische lexikographie. dordrecht: springer, 1979. [7] h. felber, terminology manual. paris: unesco, 1984. [8] r. temmerman, towards new ways of terminology description: the sociocognitive approach. amsterdam: john benjamins, 2000. [9] m. t. cabré, la terminología: representación y comunicación : elementos para una teoría de base comunicativa y otros artículos. girona: documenta universitaria, 1999. [10] p. faber benítez, “the cognitive shift in terminology and specialized translation,” monti. monografías de traducción e interpretación, no. 1, pp. 107–134, 2009. [11] p. faber benítez, a cognitive linguistics view of terminology and specialized language. berlin: walter de gruyter, 2012. [12] h. picht and j. draskau, terminology: an introduction. guildford: university of surrey, 1985. [13] e. wüster, the machine tool: an interlingual dictionary of basic concepts: comprising an alphabetical dictionary and a classified vocabulary with definitions and illustrations. london: technical press, 1967. [14] eduskuntasanasto = riksdagsordlista = finnish parliamentary glossary = soome parlamendi seletussõnastik. helsinki: eduskunta, 2008. [15] t. s. k. sanastokeskus, geoinformatiikan sanasto. sanastokeskus tsk, 2011. [16] g. a. miller, “wordnet: a lexical database for english,” communications of the acm, vol. 38, no. 11, pp. 39–41, 1995. [17] c. fellbaum, wordnet. dordrecht: springer, 2010. [18] k. parker, “hispaania värvinimed sõnastikes ja mentaalses leksikonis,” ma thesis, tallinn university, tallinn, 2013. [19] m. uusküla, “linguistic categorization of blue in standard italian,” in colour studies: a broad spectrum, john benjamins publishing company, 2014, pp. 67–78. [20] i. davies and g. corbett, “the basic color terms of russian,” linguistics, vol. 32, no. 1, pp. 65–90, 1994. [21] i. r. l. davies and g. g. corbett, “a practical field method for identifying probable basic colour terms,” languages of the world, vol. 9, no. 1, pp. 25–36, 1995. [22] a. tavast, m. uusküla, k. parker and u. sutrop, “using probabilistic conceptual graphs for representing colour terms in dictionaries,” in color and colorimetry multidsciplinary contributions, maggioli editore, 2013, pp. 455-466. [23] v. oja and m. uusküla, “mõnest värvinimetusest ja nende tähendusvahekordadest eesti ja soome keeles,” eesti rakenduslingvistika ühingu aastaraamat, no. 6, pp. 195–205, 2010. [24] c. p. biggam, the semantics of colour: a historical approach. cambridge university press, 2012. [25] i. r. davies, c. macdermid, g. g. corbett, h. mcgurk, d. jerrett, t. jerrett, and p. sowden, “color terms in setswana: a linguistic and perceptual approach,” linguistics, vol. 30, no. 6, pp. 1065–1104, 1992. [26] r. fletcher, the city university colour vision test, 2nd ed. 1980. [27] s. ishihara, ishihara’s tests for colour-deficiency. kanehara & company, 1996. [28] u. sutrop, “list task and a cognitive salience index,” field methods, vol. 13, no. 3, pp. 263–276, 2001. [29] m. uusküla, “mediterranean ecology and the colour blue in standard italian.,” in the language of color in the mediterranean, 2nd ed., forthcoming. [30] g. paggetti, g. menegaz, and g. v. paramei, “color naming in italian language,” color res. appl., p. n/a–n/a, feb. 2015. [31] d. bimler and m. uusküla, “‘clothed in triple blues’: sorting out the italian blues,” josa a, vol. 31, no. 4, pp. a332–a340, 2014. [32] g. v. paramei, m. d’orsi, and g. menegaz, “‘italian blues’: a challenge to the universal inventory of basic colour terms,” jaic journal of the international colour association, vol. 13, 2014. [33] j. sandford, “blu, azzurro, celeste: what color is blue for italian speakers compared to english speakers?” colour and colorimetry: multidisciplinary contributions, pp. 281-288, 2012. [34] l. rello, “términos de color en español: semántica, morfología y análisis lexicográfico. definiciones y matices semánticos de sus afijos.” [35] j. lillo, h. moreira, i. vitini, and j. martín, “locating basic spanish colour categories in cie l* u* v* space: identification, lightness segregation and correspondence with english equivalents,” psicológica, vol. 28, no. 1, pp. 21–54, 2007. [36] h. dyvik, “a translational basis for semantics,” language and computers, vol. 24, pp. 51–86, 1998. [37] h. dyvik, “translations as semantic mirrors: from parallel corpus to wordnet,” language and computers, vol. 49, no. 1, pp. 311–326, 2004. [38] e. héja and d. takács, “automatically generated customizable online dictionaries,” in proceedings of the demonstrations at the 13th conference of the european chapter of the association for computational linguistics, 2012, pp. 51–57. [39] e. héja and d. takács, “an online dictionary browser for automatically generated bilingual dictionaries,” in proceedings of the 15th euralex international congress, 2012, pp. 468–477. cultura e scienza del colore color culture and science 28 cultura e scienza del colore color culture and science | 03/15 1. introduction it is very interesting to study the parallel story of soap bubbles and soap films in art and science. noting that mathematicians in particular have been intrigued by their complex geometry, the interest, both scientific and artistic, was first on the colors on the surface of soap films. probably motivated by the large diffusion of paintings of children and puttos playing with soap bubbles. on december 9, 1992 the french physicist pierre-gilles de gennes, professor at collège de france, after being awarded the nobel prize for physics concluded his conference in stockholm with a poem on soap bubbles, adding that no conclusion seemed most appropriate. the poem appears as a closure to an engraving of 1758 by daullé from françois boucher’s lost painting la souffleuse de savon. de gennes did not want to allude to the allegorical meanings that soap bubbles had had for many centuries: symbol of vanity, fragility of human ambition and of human life itself. soap bubbles and soap films were one of the matters of his conference, which was entirely devoted to the soft matter. bubbles that “are the delight of our children”, he wrote. a reproduction of the engraving was included in the article. [1] soap bubbles are one of the most interesting matters in many sectors of scientific research: 1michele emmer emmer@mat.uniroma1.it 1dip. mat. “g. castelnuovo” univ. roma “la sapienza”, roma, italy colours and soap bubbles from mathematics to chemistry, from physics to biology. but not only, also in architecture and in visual arts, not to speak of design and even of advertising. a story that began so many centuries ago and it is still present. 2. art and science: a parallel history it is natural that among the first ones to be attracted by the iridescent soap films were the artists, in particular the painters. while for mathematicians soap films are models of a geometry of very stable forms, for the artists soap bubbles have been of great interest not just for their playfull aspect but as symbol, as allegory of the brittleness, of the frailty of the human things, of life. they are an aerial and light symbol, always fascinating for their endless variety of colors and forms. a series of engravings realized by hendrik goltzius (1558-1617) is the starting point of the fortune of soap bubbles in the xvi and xvii century dutch art. the best known is entitled quis evadet (who escapes) and is dated 1594. the history of the relationships between soap bubbles and visual art has been told, including numerous reproductions, in a book published in 2009 [2]. one of the most famous painting, also remembered in his writings by de gennes, was realized in the first part of the 1700s by the famous french artist jean baptiste siméon chardin (1699-1779), in different versions, under the title les bulles de savon. it is very suggestive and of a rare beauty. soap bubbles attracted chardin because of his interest in children and young people, in their world, their games. he was also attracted by the colors of soap bubbles, as the painting (it exists in three different versions) shows very clearly. it is very likely that playing with soap bubbles was a very popular children’s game at that time. and it is natural that also scientists became interested in the phenomena surrounding the formation of soap bubbles and the colors on their surfaces. it’s because i don’t do anything, i chatter a lot, you see, it’s already a month that i’ve got into the habit of talking a lot, sitting for days on end in a corner with my brain chasing after fancies. it is perhaps something serious? no, it’s nothing serious. they are soap bubbles, pure chimeras that attract my imagination. fedor dostoevsky, crime and punishment figure 1 f. boucher, la souffleuse de savon, 1758 [2] 2903/15 | cultura e scienza del colore color culture and science 3. scientists start studying soap bubbles in 1672 the english scientist hook presented a note to the royal society, later published by birch in the history of the royal society in 1756. hook wrote that with a solution of soap numerous small bubbles were blown through a small tube of glass. he noted that it could easily be observed that at the beginning the liquid film forms a spherical surface that imprisons a globe of air. it is a liquid film white and clear without the least coloration; but after a few moments, while the film is gradually thinning, all varieties of colours can be observed to appear on its surface as in a rainbow. if hook is among the first ones to attract the attention of the scientists on the problem of the formation of colours on the thin soap bubbles, it is isaac newton in opticks, [3] whose first edition is published in 1704, to describe in detail the phenomena that are observed on the surface of the soap films. in volume ii, newton describes his observations on soap bubbles. in particular he observes that if a soap bubble is formed with some water made more viscous using soap, it is very easy to observe that after a while a great variety of colours will appear on its surface. newton noted that in this way colours were disposed according to a very regular order, like many concentric rings beginning from the highest part of the soap bubble. he also observed that as the soap film became thinner due to the continuous diminution of the contained water, such rings slowly dilated and finally covered the whole film, moving down to the low part of the bubble and then disappeared. the phenomenon that newton observed is known as interference: it happens when the thickness of the soap film is comparable to the wavelength of visible light.a an easy experiment can be performed with a rectangular loom that is vertically extracted from a solution of soapy water; the light reflected by the soap film produces a system of horizontal lines, due essentially to the fact that the soap film is constituted by the two non parallel faces of the same film. in optics newton wrote: “the precedent observations were made with a rarer thin medium, terminated by a denser, such as was air or water compress’d between two glasses. in those that follow are set down the appearances of a denser medium thin’d within a rarer, such as are plates of muscovy glass, bubbles of water, and some other thin substances terminated on all sides with air. obs. 17. if a bubble be blown with water first made tenacious by dissolving a little soap in it, ‘tis a common observation, that after a while it will appear tinged with a great variety of colours. to defend these bubbles from being agitated by the external air (whereby their colours are irregularly moved one among another, so that no accurate observation can be made of them,) as soon as i had blown any of them i cover’d it with a clear glass, and by that means its colours emerged in a very regular order, like so many concentrick rings encompassing the top of the bubble. and as the bubble grew thinner by the continual figure 2 anonimous, dutch school, xvii century figure 3 d. brewster [4] 30 cultura e scienza del colore color culture and science | 03/15 subsiding of the water, these rings dilated slowly and overspread the whole bubble, descending in order to the bottom of it, where they vanish’d successively. in the mean while, after all the colours were emerged at the top, there grew in the center of the rings a small round black spot, like that in the first observation, which continually dilated it self till it became sometimes more than 1/2 or 3/4 of an inch in breadth before the bubble broke besides the aforesaid colour’d rings there would often appear small spots of colours, ascending and descending up and down the sides of the bubble, by reason of some inequalities in the subsiding of the water. and sometimes small black spots generated at the sides would ascend up to the larger black spot at the top of the bubble, and unite with it. obs. 18. because the colours of these bubbles were more extended and lively than those of the air thinn’d between two glasses, and so more easy to be distinguish’d, i shall here give you a farther description of their order, as they were observ’d in viewing them by reflexion of the skies when of a white colour, whilst a black substance was placed behind the bubble. and they were these, red, blue; red, blue; red, blue; red, green; red, yellow, green, blue, purple; red, yellow, green, blue, violet; red, yellow, white, blue, black... in the mean while at the top, which was of a darker blue than the bottom, and appear’d also full of many round blue spots, something darker than the rest, there would emerge one or more very black spots, and within those, other spots of an intenser blackness, which i mention’d in the former observation; and these continually dilated themselves until the bubble broke.” a century later after newton, david brewster wrote a paper by the title “on the colours of the soap-bubble”. [4] “the colours of the soap-bubble have been the subject of frequent observation since the time of boyle, hook, and newton, and they have been invariably ascribed not to any colour in the medium itself in which they are formed, or on whose surfaces they appear, but solely to its greater or less thickness.” the author of this paper had been led to doubt the correctness of this opinion, and while repeating the beautiful experiments of professor plateau “on the equilibrium of liquid films,” he discovered the true cause of these colours, whether they are observed on the soap bubble or on plane, convex, and concave films stretched across the mouths of closed or open vessels. the paper, which is illustrated with numerous coloured drawings, is divided into five parts. 1. on the phenomena of colour in a vertical plane film. 2. on the production of revolving systems of coloured rings on the soap film. 3. on the form and movements of the bands and rings on convex and concave films. 4. on the phenomena produced by different solutions. 5. on the origin and development of the colours on the soap bubble. in these sections the author has shown that the colouring matter of the soap-bubble is secreted from the soap solution when reduced to the state of a film;—that it rises to the highest point of the film in colourless portions, in the form of a tadpole, which pass into molecules of every possible order of colour, and then take their proper place in the coloured bands;—that these bands move over the surface of the film under the influence of gravity, and may be blown into fragments or into molecules of all colours, or even recombined with the film. “it is impossible,” the author adds, “to convey in language an adequate idea of the molecular movements, and the brilliant chromatic phenomena exhibited on the soap films, and it is equally impossible for art to delineate them.” for the scientists of the xviii century the connection among the soap bubbles and some natural phenomena that follow schemes of maximum and minimum was not at all clear; only in the xix century it will be understood that soap bubbles furnish an experimental model for problems of mathematics and physics, inserting soap films to full title in the sector of mathematics called calculation of the variations. 4. a blind mathematician one of the most important problems for which soap bubbles and soap films furnish an experimental model of the solution is called the plateau problem, from the name of a belgian physicist. the general mathematical solution to the problem of plateau was difficult to obtain. antoine ferdinand plateau (1801-1883) began his scientific career in the field of astronomy. in 1829 during an experiment he exposed too long his eyes to sunlight, causing irreversible damage to his sight. since 1843 he was completely blind. he took an interest in the nature of forces in molecular fluids, to discover the forms that generate soap films contained in metal wires immersed into soapy water. in 3103/15 | cultura e scienza del colore color culture and science 1873 he published the result of fifteen years of research in two volumes: ‘statique expérimentale et théorique des liquides soumis aux seules forces moléculaires’ [5] plateau himself introduced the general principle that is the basis of his work. the idea is to draw a closed contour with the only condition that it contains a limited portion of the surface and that it is compatible with the surface itself; if then a wire identical to the previous contour is constructed, plunged entirely in the soapy liquid and then pulled out, a set of soapy films is generated representing the portion of area under consideration. plateau cannot do without noting that these surfaces are obtained ‘almost by magic.’ and here is the great discovery of plateau, incredible at first sight: however high the number of soap films that come into contact with each other, there can be only two types of configurations. precisely the three experimental rules that plateau discovers about soap films are: 1) a system of bubbles or a system of soap films attached to a supporting metallic wire consists of surfaces flat or curved that intersect with each other along lines with very regular curvature. 2) surfaces can meet only in two ways: either three surfaces meeting along a line or six surfaces that give rise to four curves that meet in a vertex. 3) the angles of intersection of three surfaces along a line or of the curves generated by six surfaces in a vertex are always equal in the first case to 120°, in the second to 109 ° 28 ‘. another question remained still open: were the laws discovered experimentally by plateau for the geometry of soap films correct or not? “in this work we provide a complete classification of the local structure of singularities in the three-dimensional space, and the results are that the singular set of the minimal set consists of fairly regular curves along which meet three films of the surface with angles equal of 120 degrees and isolated points where meet four of these curves giving rise to six films also with equal angles. the results apply to many real surfaces that are generated by surface tension, as to any aggregate of soap films, and so provide a proof of experimental results obtained from plateau over a hundred years ago.” thus begins one of the best known work of mathematics of last century. written by jean e. taylor, entitled the structure of singularities in soap bubble-and-like soap-film-like minimal surfaces. [6] fred almgren and jean taylor wrote a well known article on their research published in scientific american in 1976. [7] in 1979 i realized the film soap bubbles, in the series art and mathematics, starring fred almgren and jean taylor. [8] the film was made at princeton university, using real models with soapy water, while in the new film on minimal surfaces produced by a. arnez, k. polthier, m. steffens and c. teitzel at university of bonn and at technical university of berlin in 1995 all models are made with computerized animation. [9] in both films the brilliant colours of soap films and bubbles have a fundamental role. of course the new computerized soap does not alter the charm of playing with real soap bubbles! mark twain was right when he wrote: ‘a soap bubble is the most beautiful and most elegant object, that there is in nature ..... i wonder what would be required to buy a soap bubble if in the world there existed only one.’ 5. soap bubbles in art and arhitecture the famous french artist manet painted les bulles des savon in the same years of the publication of the research of plateau some years after d’arcy thompson in the book on growth and form, [10] a classic book dedicated to the study of animal forms using mathematical models, devotes a chapter to the discoveries of plateau and the use of his laws on soap films to explain the shape of some of the radiolaria. “the peculiar beauty of soap bubbles, the resulting forms, are so pure and so simple that we come to look on them as a mathematical abstraction”, wrote d’arcy thompson. since the publication of the book by thompson some of the images have been always linked to the geometry of soap films. images that have influenced many designers, artists and architects. [1] when in 1976 the mathematician jean taylor proved that the laws of plateau were correct, a student of art, bradley miller, went to princeton university where taylor worked together with her husband fred almgren. miller had the idea of using photography to fix the structure of soap films. these images were printed in an art book in 2007 [11] and were on show in a gallery in venice during the annual congress on mathematic and culture. in 1890 boys completed his book soap bubbles, [12] in which he summarized his own experience in explaining to a large public the geometry of soap bubbles and soap films: 32 cultura e scienza del colore color culture and science | 03/15 “i do not suppose that there is anyone who has not occasionally blown a common soap bubble, and while admiring the perfection of its form, and the marvelous brilliancy of its colour, wondered how such a magnificent object can be easily produced. i hope that none of you are yet tired of playing with bubbles, because as i hope we shall see, there is more in a common bubble that those who have only played with them generally imagine.” in his book boys published a colour plate on the colour on the surface of soap bubbles and soap films. in the xvith century colour in soap bubbles became fascinating to children and artists, like chardin and manet. in the xviith century those colours attracted scientists like newton. the interest they aroused has never come to an end. as foreseen by lord kelvin, artists, architects, mathematicians, physicists and biologists among others continued to study colour and shape in soap films throughout the centuries. the story of soap bubbles in art and science is a never ending story... notes a) for more details http://hyperphysics.phy-astr.gsu.edu/ hbase/phyopt/soapfilm.html bibliography [1] p.g. de gennes “soft matter”, science, vol 256, april 24 th 1992, pp. 495-497. [2] m. emmer, bolle di sapone tra arte e matematica, bollati boringhieri, torino, 2009. premio letterario viareggio per la saggistica 2010. [3] newton, opticks or a treatise of the reflections, refractions, inflections & colours of light, reprinted cosimo, new york, 2007 [4] david brewster ,“on the colours of the soap-bubble.”, transactions of the edinburgh bibliographical society, vol. 25, pt. 1, 1867, p. 491. [5] j. plateau, statique expérimentale et théorique des liquides soumis aux seules forces moléculaire, gauthiervillars, paris 1873. [6] j. taylor, the structure of singularities in soap-bubblelike and soap-film-like minimal surfaces, annals of mathematics, vo. 103, 1976, p. 489-539. [7] f. alngren & j. taylor, the geometry of soap bubbles and soap films, scientific american, july 1976, p. 82-93. [8] m. emmer,” soap bubbles”, film & dvd, colour, sound, 25 m., emmer prod., rome, 1979. [9] a. arnez, k. polthier, m. steffens and c. teitzel, toucing soap films, film dvd, colour, sound, 41 m., springer, berlin 1999. [10] d’arcy thompson, on growth and form, vol.1, cambridge university press, cambridge 1942. [11] b. miller, bubble shadows, anderson ranch arts center, snowmass, col., 2006 b. miller, “bubble shadows”, in m. emmer, ed., matematica e cultura 2008, springer, milano, p. 323-331. [12] v. boys, soap bubbles. their colours and the forces which mould them, dover, new york, 1959. 90 color culture and science journal vol. 11 (2) doi: 10.23738/ccsj.110210 evaluation of the perceived colour difference under different lighting for museum applications alice plutino1, laura grechi1, alessandro rizzi1 1 mips lab, dipartimento di informatica, università degli studi di milano, milano, italy. corresponding author: alice plutino (alice.plutino@unimi.it) abstract the role of lighting in museums has a fundamental importance. light influences the perception of colours and space in the collections on display, therefore, any type of lighting must be adequately analysed to confirm the suitability and undistorted colour rendering of the illuminated objects. a two-stage perceptual test was carried out for this purpose. initially, the participants were asked to evaluate the illuminants according to criteria such as: the brilliance of the colours, the degree of pleasantness of the lighting and the degree of overall satisfaction of the setting. subsequently, the efficiency of different illuminants for the identification of colour differences between two objects was tested. the results obtained were then compared with the most commonly used colour rendering and colour difference indicators in order to determine their potential and limits. keywords lighting, colour perception, cri, museum lighting received 31 october 2019; revised 16 november 2019; accepted 22 november 2019 evaluation of the perceived colour difference under different lighting for museum applications 91 color culture and science journal vol. 11 (2) doi: 10.23738/ccsj.110210 1. introduction in museums, the role of lighting is often linked to the creation of an immersive and evocative experience for the viewer when visiting the collections. in this context, although the regulations for lighting that does not cause damage to the illuminated objects and to the users are respected, often the lights are not subjected to an analysis that confirms their adequacy and ensures a correct color rendering of the objects on display (feller 1968, camuffo 2014). the experiment we are presenting can be divided into two main parts: evaluation of light sources and evaluation of colour differences. in recent years, several experiments have been carried out in order to evaluate the perception of the colour of museum objects under different light sources (boissard & fontoynont, 2009, pinto et al. 2008, pinto et al. 2006, scuello et al. 2004), focusing primarily on colour temperature and the study of leds. nevertheless, it is difficult to integrate the elaboration of the visual system in the calculation of the colour perception and often it is reduced to evaluating a source based only on emission and reflectance spectra. for this reason, it was decided to have users evaluate three main characteristics of the colour rendering: the brilliance of the colours, the pleasantness in relation to the lighting and the degree of overall satisfaction of the set-up. the aim of the brillance assessment is to determine how much the illuminant promotes the colour rendering of an object on display. the term pleasantness refers to the illuminant and is designed to determine which light is most pleasing to the viewer, not considering, therefore, the color rendering of the object. finally, with the term satisfaction, we ask you to evaluate the entire installation. in addition to illuminants, the study of colour rendering in museums in recent years has also been the subject of many studies, aimed at determining which source guarantees better colour rendering and, if there are preferable sources, for the lighting of specific museum objects (viénot et al. 2011, nascimento & masuda 2012, nascimento & masuda 2014, vázquez et al. 2012). in this context, in the second part of the experiment, users were asked to compare the colours of two colour checkers (see section 2), to determine how much the illuminant influences the perception of colour differences. the results of these two experiments were compared with the most common colour rendering and colour difference indexes. the aim of this study is to demonstrate that colour rendering is a complex concept in its definition and that the most common indexes are not enough effective to represent the perceptual variations of colour. the applicability of the results obtained has been evaluated in the light of a complex field of application such as that of the museum, where for an exhibition lighting must be considered in terms of conservation, exhibition and use. in addition, the limits of colorimetric measurements, which are not reliable in the presence of spatial arrangements and different lighting conditions, are to be highlighted. 2. materials and methods for this experiment, the use of the gretag macbeth colour checker, in original and printed version (figure 2a), using a printer laserjet pro 400 colour. both colour checkers have been positioned within a light booth, model the judge ii, equipped with 4 different types of light sources: cie d65, cool white fluorescent, u30tl84 and illuminant a. two led lights have been added to the light booth: one 'cold' (led 1, 5000k) and one 'warm' (led 2, 2500k). the uniformity of the light diffusion was verified on the basis of the light booth for all the lights. the emission spectra of each individual source were measured with a cl-500a spectrophotometer (spectra in figure 1, measurement set-up in figure 2b) which, during the measurements, was placed in the centre of the light booth on the same support as the colour checkers. from the emission spectra of the sources the following were calculated: cri (colour rendering index) (oleari, 1998), tm-30 fidelity index and tm-30 gamut index (society, 2018). fig. 1. emission spectra of illuminants the reflectance spectra of the patches of the two versions of the colour checker were measured using an ocean optics hr4000 spectrophotometer. the data thus obtained were then processed to obtain the colorimetric values in the l*a*b* colour space by simulating the illumination under the various light sources present in the light booth. finally, the chromatic differences (values ∆e and ∆e00) between the patches of the original colour checker and the corresponding ones of the printout were calculated. evaluation of the perceived colour difference under different lighting for museum applications 92 color culture and science journal vol. 11 (2) doi: 10.23738/ccsj.110210 the perceptual test was carried out on 20 people, none of whom had problems with colour perception. the test, performed inside a dark room (figure 3) without windows and without artificial lights on except for the light booth, was carried out in two parts: a) evaluation of the light sources: with the use of a guided table it was asked to indicate with an evaluation from 0 to 100 the brilliance of the colours, the degree of pleasantness referred to the light source and the degree of general satisfaction of the setting. the term brilliance was used because in the common language it is associated with the perceived brightness of the colours. it was decided not to use the term saturation or tone, as it is particularly specific and difficult for non-experts to understand. this operation has been done alternating for each source, the original colour checker (mccamy et al. 1976, pascale 2006) to the printed one so as to avoid that the judgment was subject to comparison between the two. fig. 2. (top) original (left) and printed (right) colour checker inside the light booth. (bottom) set-up of the cl-500a spectrophotometer during measurements. b) evaluation of colour differences: it was asked to indicate with an evaluation from 1 to 5, (where 1=identical patches and 5=absolutely different patches), the colour difference between 15 selected patches of the original colour checker and the corresponding printed patches (figure 4) (mccamy et al. 1976, pascale 2006). this subjective colour difference assessment was carried out under all light booth sources. to solve the numerical problem of estimating the magnitude between different colors, the "neutrals" tab of the munsell book of colours was used as a framework. for example, the magnitude between patches n9 (white) and patches n7/n8 (light grey) corresponds to a difference of 1, while patches n9 and n3/n2 (dark grey) have a difference of 3. 3. results 3.1. evaluation of light sources the table below shows the cri, colour temperature and tm-30 values of the fidelity index (table 1). figure 5 shows the results of the subjective evaluation of brilliance, pleasantness and satisfaction for each individual source. daylight a cwf u30tl84 led 1 led 2 cri (ra) 94 99 59 87 94 83 t colour(k) 7000 2600 3900 3000 4800 3000 fidelity index (rf) 94 99 67 82 93 84 tab. 1. cri (ra), t colour, rf values of the various illuminants. 3.2. evaluation of colour differences the following table summarises the values δe and δe00 calculated from the reflectance spectra of each patch of the colour checker under all the sources present in the light booth (figure 6). all calculated δe values have been compared with the average of the values assigned by users as shown in figure 7, figure 8, figure 9, figure 10 and figure 11 and figure 12. 4. discussion the results of the perceptual test showed some discrepancies between the calculated indexes and the perceived values in the evaluation of illuminants and colour differences. 4.1 evaluation of illuminants with regard to the assessments of brilliance, pleasantness and satisfaction, it is interesting to note that the scores awarded by users never reach the high scores awarded by the cri index (figure 5 and table 1) (fumagalli et al. 2013). the exception is the illuminant cwf of which the printed version of the colour checker has slightly lower perceptual values, but substantially similar, compared to those of the cri, while the score assigned to the original version is higher. evaluation of the perceived colour difference under different lighting for museum applications 93 color culture and science journal vol. 11 (2) doi: 10.23738/ccsj.110210 fig. 3. user-assigned values in % for three parameters: b=brilliance, p=pleasantness, s=satisfaction fig. 4. δe (top) and δe00 (bottom) values calculated under the different illuminants in the light booth evaluation of the perceived colour difference under different lighting for museum applications 94 color culture and science journal vol. 11 (2) doi: 10.23738/ccsj.110210 fig. 5. perceptual test values compared with the measured values of δe and δe00 for illuminant d65. fig. 6. perceptual test values compared with the measured values of δe and δe00 for illuminant "a". fig. 7. perceptual test values compared to measured values of δe and δe00 for illuminant "cwf". fig. 8. perceptual test values compared with the measured values of δe and δe00 for the illuminant "u30tl84”. fig. 9. perceptual test values compared with the measured values of δe and δe00 for the led illuminant1. fig. 10. perceptual test values compared to measured values of δe and δe00 for led illuminant2. evaluation of the perceived colour difference under different lighting for museum applications 95 color culture and science journal vol. 11 (2) doi: 10.23738/ccsj.110210 it is clear that the original version of the colour checker under all illuminants is much more appreciated by users, who always give it very high scores, indicating that the support and materials used for any coloured object have a fundamental importance for good colour rendering. considering the overall satisfaction value, the illuminants that received the highest scores from users were illuminant d65, a and led1. this evaluation is consistent with the values of cri and tm-30 fidelity, as these measurements also assign higher values to the illuminants themselves. note that the led1 scored high according to these two indexes because, being of the new generation, the emission spectrum was modified by the production company in order to meet the cri index standardized by the cie commission. in addition, the values assigned by the tm-30 fidelity index do not differ particularly from the cri. considering the values of brilliance and pleasantness, there are major discrepancies between the subjective judgment and the colour rendering indexes. according to the brightness values, in fact, the led1 has the highest value, followed by a, cwl and u30tl84 for the original colour checker, while for the printed version the highest brightness is given by the u30tl84 and led1. considering the pleasant lighting value for the original, the best illuminant is a, followed by led1, while the printed led1 obtains the highest scores, followed by a. these results cast doubt on the colour rendering indexes, which do not consider the perceptual component of colour processing by the subjects, as well as the colour adaptation and spatial context variables. 4.2. evaluation of colour differences with regard to the measurement of colour differences (δe and δe00), it can be seen that in general the values are always high (except in specific cases), due to the characteristics of the substrate and the dyes that have very different reflectance spectra. the purpose of the experiment is to highlight under what conditions the colorimetric and precise measurement of δe is not sufficient to determine the metering of two colours under different lighting conditions. considering the values of δe and δe00, it is evident that the measured values are significantly higher for the illuminant d65. in addition, when comparing the individual patches, higher colour differences are obtained for those with higher blue components (bluish green, purplish blue, blue sky, blue flower) (brueckner et al. 2009). when comparing the illuminants, cwf and led2 maintain the smallest difference values. the comparison between the various illuminants does not reveal a general predominance for the subjective values compared to those calculated but depending on the patch and the type of lighting, the results assume very different values. despite this, it is noticeable that patches with a strong blue component, assume values of high colour differences, while they generally assume lower values both for patches with a strong red component (orange and moderate red) and for those in shades of grey (white 9.5, neutral 6.5, black 2), with a few exceptions. patches with a strong red component and patches in shades of grey obtained lower values both in the calculated ∆e and in comparison, to the scores assigned to all the others. considering illuminant d65 (figure 7), the differences noted by the subjects are always greater than 2, with a peak of difference for the purplish blue that assumes values close to 5. looking at the values for the illuminant a (figure 8), there is a general decrease in the values of subjective difference, so the peak for patch 10 remains, but falling to a value of about 4.3. for white, yellow green and moderate red the difference values are close to 1.5 so they are considered perceptively very close to those of the original colour checker. considering the illuminant cwf (figure 9), the values of dark skin and purple are considered more similar to the original, while the colour difference of purplish blue returns to values of about 4.5. in this case the values of δe and δe00 are much lower than in the case of d65 and a. as for u30tl84 (figure 10) the difference for yellow green and dark skin is subjectively around 1.5 the values of δe and δe00 decrease for purplish blue but remains around 4.5 in subjective judgment. finally, as far as led1 (figure 11) is concerned, the perceptual differences between the original and the printed one increase compared to the other illuminants and present a similar trend to d65, even if lowered by about 1 point. in led2 (figure 12) the subjective values are very similar to led1, with some differences for some blue/green patches that have lower subjective values and some of the red-orange patches that have higher values. from these evaluations and from the graphs we can see, therefore, a strong discrepancy between the δe and δe00 colorimetric values measured from the spectra to the perceptual values given by the evaluation of the subjects involved in the study, differences that are not given simply by a physical component of reflectance compared to an illuminant, but by a strong perceptual component. this is because both measurements δe and δe00 do not consider the spatial arrangement of colours in the evaluation of the perceived colour difference under different lighting for museum applications 96 color culture and science journal vol. 11 (2) doi: 10.23738/ccsj.110210 evaluation and adaptation of the human visual system to the different illuminants. 5. conclusion in this study it is shown that the colour rendering indexes are not adequate to give an estimate of the perceptive rendering of an illuminating and to maintain metamerism. moreover, it has been demonstrated that a colorimetric measure of local colour difference is not sufficient to represent the perceptual variations of colour with the variation of illuminants and in the presence of a spatial arrangement. a further limitation to these measures lies in the fact that they do not consider the colour adaptation of the human eye, the surrounding illumination and the signal processing by our visual system. this aspect can be seen above all from the answers to the perceptual test on colour differences where it became clear that some users had the ability to recognize and preserve the variations between two coloured patches even under different illuminants. moreover, in most cases there was no correspondence between the values acquired with the experimental measures and those assigned by the perceptual test. for applications in the museum environment, provided that the regulations for lighting that does not damage the objects on display and the users are respected, it can be seen that as far as lighting is concerned, the supports and materials used in the enjoyment of the exhibition will always be of greater importance, so the object will always be of primary powerlessness. moreover, it has been seen that led lights far exceed the d65 standard in the creation of a satisfactory exhibition space and for a pleasant and apparently correct reproduction of colours. moreover, when evaluating sources for complex exhibition spaces, it must be taken into account that both the cri and the fidelity index do not consider the spatial arrangement and the systems for adapting the eye to lighting, so if only one of these aspects is taken into account in the evaluation methods without considering the others, the comparison between the data and reality can never be considered satisfactory. in conclusion, since many differences have emerged between the perceptual test and the values measured experimentally, both regarding cri, δe and δe00, it is considered necessary to reconsider the methods and uses of both parameters to ensure that they are more reliable and consistent with reality. number the illustrations according to their sequence in the text. submit each illustration as a separate file (indicate where the figure should be placed in the text). ensure that each illustration has a caption. supply captions separately, not attached to the figures. a caption should comprise a brief title (not on the figure itself) and a description of the illustration. keep text in the illustrations themselves to a minimum but explain all symbols and abbreviations used. if visuals from other copyrighted publications are to be included in the manuscript, it is the author’s responsibility to secure permission to publish these in the journal before submitting the manuscript for review. 6. conflict of interest declaration the authors declare that there is no conflict of interest with other people or organizations. 7. funding source declaration this research did not receive any specific grant from funding agencies in the public, commercial, or not-forprofit sectors. 8. short biography of the author(s) alice plutino she is a phd student in computer science at the university of milan. she obtained her master’s degree in conservation science for cultural heritage at the same university. now, she is focusing on colour correction, image enchantment and image quality assessments. she is author of different papers concerning innovative methods for film restoration and digital restoration assessments. laura grechi she is a graduate of the master course in conservation science for cultural heritage at university of milan. she obtained the master’s degree in october 2019. during her curricular internship at the university she carried out experiments studying colour differences between human perception and colour rendering indexes. alessandro rizzi he is full professor at the department of computer science at the university of milan. from 1990 his research has been in the field of colour, digital imaging and vision. he is particularly focused on colour, visualisation, photography, hdr and on the perceptual issues related to digital imaging, interfaces and lighting. he is the head of the mips lab at the department of computer science and was one of the founders of the italian colour group, secretary of cie division 8, is&t fellow and vice president. in 2015 he received the davies medal from the royal photographic society. he is co-chair of the is&t conference “color imaging: displaying, processing, hardcopy and applications”, a member of several programme committees of conferences related to colour and digital imaging, and author of about 300 scientific works. evaluation of the perceived colour difference under different lighting for museum applications 97 color culture and science journal vol. 11 (2) doi: 10.23738/ccsj.110210 references boissard, s., & fontoynont, m. (2009). optimization of led-based light blendings for object presentation. color res. appl. 34, 310-320. brueckner, s., bodrogi, p., & khahhn, q. t. (2009). colour rendering of new white led light sources visual tests. lux eurpoa, pp. 397-404. camuffo, d. (2014). microclimate for cultural heritage conservation, restoration, and maintenance of indoor and outdoor monuments. elsevier. feller, r. l. (1968). control of deteriorating effects of light on museum objects: heating effects of illumination by incandescent light. . museum news. technical supplement, 46(9), 33 47. fumagalli, s., bonanomi, c., & rizzi, a. (2013). an experiment on the color rendering of different light sources. color imaging xviii: displaying, processing, hardcopy and applications, is&tspie electronic imaging, 3-7february 2013, san francisco (usa). mccamy, c. s., marcus, h., & davidson, j. g. (1976). a color rendition chart. journal of applied photographic engineering 11 (3), pp. 95-99. nascimento, s. m., & masuda, o. (2012). psychophysical optimization of lighting spectra for naturalness, preference, and chromatic diversity. josa a, 29(2), a144-a151. nascimento, s. m., & masuda, o. (2014). best lighting for visual appreciation of artistic paintings—experiments with real paintings and real illumination. josa a, 31(4), a214-a219. oleari, c. (1998). misurare il colore. hoepli. pascale, d. (2006). rgb coordinates of the macbeth colorchecker. pinto, p. d., linhares, j. m., & nascimento, s. m. (2008). correlated color temperature preferred by observers for illumination of artistic paintings. josa a, 25(3), 623-630. pinto, p. d., linhares, j. m., carvalhal, j. a., & nascimento, s. m. (2006). psychophysical estimation of the best illumination for appreciation of renaissance paintings. visual neuroscience, 23, 669-674. scuello, m., abramov, i., gordon, j., & weintraub, s. (2004). museum lighting: optimizing the illuminant. color res. appl., 29, 121-127. society, i. e. (2018). ies methods for evaluating light source color rendition. isbn-13: 978-87995-379-9. vázquez, d., de luna, j. m., alvarez, a., sánchez, a., & sedano, u. (2012). study of chromatic variations between metameres by varying the lighting in the painting" boy in a turban holding a nosegay. optical systems design, international society for optics and photonics, 8550. viénot, f., coron, g., & lavédrine, b. (2011). leds as a tool to enhance faded colours of museums artefacts. journal of cultural heritage. 12(4), 431-440. 18 color culture and science journal vol. 12 (1) doi: 10.23738/ccsj.120102 color as a sign of urban transition in the city of bordeaux aline barlet1, audrey bousigues1, alice herbert1 1 greccau laboratory, ensapbx, bordeaux, france. aline.barlet@bordeaux.archi.fr, audrey.bsgs@gmail.com, alice-herbert@orange.fr corresponding author: aline barlet (aline.barlet@bordeaux.archi.fr) abstract color in architecture, despite its functions as a signal, a landmark and a symbol, remains largely absent at both the urban level and at the building level. the trend is towards the color chart, seeking harmony, but which sometimes gives way to monotony. in the case of a heritage city such as bordeaux, the question of the use of color has also to cope with the unesco world heritage protection of a large part of the city. actions are limited by a concern for the relationship with what exists already, and as a result, respect for the historic and visual context gives rise to architectures that are discreet, or sometimes even banal. nevertheless, there are designers in bordeaux who dare to use color. most colored buildings are part of a specific program or are in a key location in the city. by analyzing some urban and architectural examples, we show that buildings may be located in places of urban divide or that color may be used to identify a specific function. logically, the further we move from the historic city center, the more colored buildings we encounter, yet colors nevertheless seem to be complex to manage. however, by determining the predominant colors and identities of a place, it is possible to focus a project more precisely and make it easier for residents to appropriate the space. keywords color, architecture, heritage, function, visual integrity received 15 october 2019; revised 16 december 2019; accepted 07 january 2020 color as a sign of urban transition in the city of bordeaux 19 color culture and science journal vol. 12 (1) doi: 10.23738/ccsj.120102 1. color and architecture color is an integral part of our daily lives. color conveys codes, taboos, and prejudices that we adhere to without knowing it. it influences our environment, our behavior, our language and our imagination (déribéré 1964). in every country in the world, since prehistoric times, man has been attracted by color, creating symbolic messages around it that have been passed down through the ages in diverse activities and have become imprinted in his subconscious. in the field of architecture, while color is ubiquitous in interior decoration, it is more unusual to find it used on façades, apart from the color of the materials themselves. 1.1. the many functions of color in architecture color in architecture becomes a signal in our environment when it contrasts with its urban context. color can assume different functions in architecture. when used as a landmark, it helps to find a place, and gives a city ’legibility’ as described by david lynch (1960). when used as a symbol, it becomes a collective sign, the result of an historical-social convention. it mobilizes people around a community identity, a basis for recognition and membership of a group (soulié 1988). the color of buildings and urban spaces enables us to find our way, to find our identity, and to dream. however, above all, color is the means by which the architect is able to express his sensitivity, his tastes, and his desires. following trends is therefore neither an obligation nor a necessity. today, however, the color chart is widely used and restricts the possible color choices for architectural façades, seeking harmony and thus giving way to repetition and sometimes monotony. 1.2. patrimonialization and coherence: many channels of vigilance many cities that are unesco world heritage sites, such as bordeaux, are ‘living historic cities’ and continue to evolve. as a result, the aim of the approach proposed by unesco (2011) is to ensure that contemporary interventions blend harmoniously with heritage in a historic framework. in the case of bordeaux, as described by callais and jeanmonod (2017), unesco recommends a degree of vigilance regarding “the coherence and unity of the ensemble of classical and neoclassical buildings […] and the quality of the public spaces.” some buildings, however, are colored with different and remarkable colors contrasting with the dominant colors of the surrounding context. some other buildings are of natural materials, contributing to a rather monochrome landscape. in order to respect the requirement to maintain a relationship with the existing architecture, the city of bordeaux is well equipped with tools and experts. we should mention the club (local bordeaux unesco committee), which has an advisory role in architectural and urban projects. the psmv (safeguarding and enhancement plan) deals with the area within the protected perimeter, and the plu (local urbanism plan) with heritage throughout the rest of the city and protection of the areas around historic monuments across virtually the entire city. the abf (architect for the buildings of france) supervises all projects carried out within the protected areas. fig. 1. location in bordeaux of buildings discussed. 1.3. color and visual integrity in bordeaux today, the only projects that are permitted are those which are simple and unremarkable in style, with a stone façade, and which do not disrupt the landscape, or projects whose architectural quality can allow for a degree of individuality, especially through color, and particularly in the case of public facilities. in some cities, unesco experts have refused projects because they detracted from the city’s visual integrity. this is defined as the means of “identifying, conserving and managing historic areas within their broader urban contexts, by considering the interrelationships of their physical forms, their spatial organization and connection, their natural features and setting, and their social, cultural and economic values.” (unesco 2011). color as a sign of urban transition in the city of bordeaux 20 color culture and science journal vol. 12 (1) doi: 10.23738/ccsj.120102 however, being listed as a world heritage site is not necessarily a constraint to architects’ creativity. some designers venture to use color, whether at the urban scale or the architectural scale. in this paper we explore the various manifestations of color to be found in the city of bordeaux and identify their specific features by analyzing a few examples (fig. 1). 2. the colors of the city when we talk about color in a city, we must first distinguish between short-lived color and long-lasting color. short-lived color lasts for only a short time and includes advertising posters, paintings, street art, shop signs, etc. these colorful elements are ubiquitous in urban space and may even be predominant in relation to the color of the architecture. therefore, short-lived color should not be neglected in the case of a global approach of color in urban areas. long-lasting colors give a place its chromatic identity, whether the colors are natural or created artificially using dyes. jean-philippe lenclos (1982) talks about the “geography of color” as the result of close interactions between the use of materials found on-site and the application of colors linked to local traditions. in bordeaux, the stone has a range of hues, associated with different local quarries, and these dominate the landscape of the historic center, giving it its homogeneity (fig. 2). however, bordeaux history shows that it was not always like that. in the middle ages, colors were only on public monuments and homes were characterized by halftimbered façades. bordeaux was then the city of wood. then, the façade coatings from the 14th to the 19th centuries, as well as natural or varnished brick introduced by the art nouveau and art deco movements of the early 20th century, led to the colors of bordeaux, in a city of stone mostly built in the 17th,18th and early 19th centuries. fig. 2. bordeaux, city of stone. photos © a. herbert. subsequently, the modern movement was accompanied by two postures regarding the use of color in architecture. on the one hand, architects such as adolf loos (1913), defending the notion of truth in architecture, claimed that ornament (and thus color) was a crime and therefore refused to apply color to natural building materials. some decades earlier, john ruskin (1880:137) stated: “i think the colours of architecture should be those of natural stones; partly because more durable, but also because more perfect and graceful.” yves charnay (2017), however, claims that material alone does not explain the use of the restrained stone colors. rather moral and ideological reasoning going back to the 12th century has profoundly influenced french culture. cistercians, thus, in contrast to abbot suger of st denis, regarded color and ornament as representations of vanity but associated color of natural materials with truth and beauty. on the other hand, color could be used to mark volumes or to make architecture more abstract such as promoted by the dutch art movement de stijl. in la cité frugès in pessac, le corbusier used color to enhance space because “gray cement houses make an unbearable compressed clump, without air” (barba and peinado 2017). therefore, bordeaux has been marked by different architectural styles over time, bringing other new colors to the architecture. now, when an urbanization or architectural project is carried out, color is used either to enable the project to merge into its setting, or to differentiate it. although stone is the predominant material in bordeaux, building in stone or respecting the stone color tones is not a stipulation in the planning documents. although there is no stipulation, a certain hierarchy emerges in bordeaux, linked to the nature of the urban landscapes and the degree of heritage protection. the further we move from the historic center, the more freedom we see in the choice of colors. for example, the bassins à flots district is differentiated from the historic city (fig. 3). it has uniformity through its dominant material, metal. the colors of the metal cladding are varied, ranging from blue-gray to azure through black. the city of stone and the city of metal are adjacent yet differentiated, while both have the same underlying principle, that of unity. color as a sign of urban transition in the city of bordeaux 21 color culture and science journal vol. 12 (1) doi: 10.23738/ccsj.120102 fig. 3. the bassins à flot district: two apartment buildings. photos © a. herbert. architects are rational in justifying their choice of colors for a project. this was the case for the wine museum cité du vin (2016) designed by agence xtu (fig. 4), whose “golden highlights evoke the blond (golden) stone of the bordeaux façades.” fig. 4. cité du vin. photo © a. herbert. to objectify the choice of colors as much as possible, it is interesting to understand the surrounding colors in which the project is created. in this way, the colors of a building can be defined more precisely according to the approach to be adopted (tone on tone, contrast, and more). despite the development of these methods, color still eludes us and always has an element of subjectivity. however, by determining the dominant colors that identify a place, as can be carried out for example using lenclos’ method (1982), one can position oneself more rightly within a project. this enables a better appreciation of the color context. the color choice is then not just a personal but a more objective, issue. color is complex to manipulate, this is why there are different systems and tools available, such as color charts, to help deal with color in the city, especially in a historic city. the complexity of the issue lies in the balance between the preservation of a chromatic identity and creative freedom. 3. colored architectures differentiating a building from its context is not a straightforward process, nor is it without repercussions; the decision must justify the risk, otherwise it can result in the city being less legible with many landmark buildings. noury (2008:124) points out that, “regarding colored architecture, there are two ways in which it can be embedded into its surroundings: integrating a new building into the urban landscape by harmonizing shades of color, or making a new construction contrasting visually with its environment.” in bordeaux, we find that most contemporary colorful buildings are part of a specific program or are in a key location in the city. 3.1. color as transition in the city the hotel seeko’o, located at the corner of cours edouard-vaillant and quai de bacalan, was completed in 2007 by king kong architects (fig. 5). the remit was to produce a high-end hotel, and this building aspires to be seen and to be a reference point in the city. what is striking at first is its large volume made up of perfectly smooth white corian©. according to the architects, the project was designed on the scale of the city and connections between the neighborhoods. fig. 5. hotel seeko’o. photo © a. herbert. although a large part of the bordeaux quayside offers up a uniform landscape, the urban fabric in this part of the city is “freer and less ordered”, according to costedoat (2007). traditional in terms of its urban location yet contemporary in its architectural style, construction material and color, the seeko’o perfectly masters its role in the transition between the classical city and the renewal taking place in the northern neighborhoods. square pey berland also illustrates this urban transition (fig. 6). designed in 2006 by architects arsène-henry and triaud, this building contains apartments, offices and shops and is located at the junction between the traditional color as a sign of urban transition in the city of bordeaux 22 color culture and science journal vol. 12 (1) doi: 10.23738/ccsj.120102 city and the largely concrete-dominated ensembles in the mériadeck district. fig. 6. square pey berland. photo © a. bousigues. with its façade cladding with brazil stone colored brown ochre, it has been nicknamed the ‘gingerbread’ building. when the sun shines on it, the block looks very bright. this is a very heterogeneous building in a heterogeneous place, creating the link between the classical city and the modern city, and is a reference point in the landscape. finally, the arc-en-ciel building, designed by the architect bernard bühler, is also located at the edges of different sections of the city, between the city of stone and some of the new urban ensembles (fig. 7). fig. 7. arc-en-ciel building. photo © a. herbert. as its name suggests (‘rainbow’ in french), the specific feature of this social housing complex is its aesthetics, defined, beyond its overall form, by glass strips in a dozen different and contrasting colors which alter the perception of natural light. the architect justified this approach by the need to enhance social housing, which, in his opinion, is usually “sad and somber”. although the intentions of the architect, here or in other examples, are to enhance social housing and make it an enjoyable place to live, it can be argued that paradoxically, this addition of color may in itself be stigmatizing. indeed, the use of color is often reserved for this type of housing. 3.2. color as a means of identification putting color on the front of one’s home is a means of appropriation; it makes the building stand out from the rest. this color is a sign of identification for its occupants, it defines a unique space, their home; a customized dwelling which seems to be everyone’s dream. if we consider collective housing, then the theory is quite different. the occupants are distanced from these issues and the framework for decision-making seems to give the architect sole responsibility for this choice. if we look at the different stages in the design of the façades of the stadion building, we see how this decisionmaking takes place in a way that is becoming more and more widespread (fig. 8). fig. 8. the stadion. photo © a. bousigues. the stadion is a collective housing building containing 15 homes, built by ls architects and associates in 2011 on one of the bordeaux boulevards. the site marked by a great architectural diversity, even with the presence of buildings with exceptional architecture, legitimizes the proposal of a unique building in terms of color. on its contemporary façade, volumes are highlighted in gray and yellow. these colors were chosen after a three-way discussion between the architect, the city’s architectconsultant and the client. the objective was to use a material that would enhance the aesthetic aspect of the building while being resistant and affordable financially. 3.3. color and materiality the colors on the façades of the stadion are used differently. the reconstituted fiberboard panels, the main constituent element of the façade, are through-dyed in gray. the manufacturer guarantees the consistency of the color as a sign of urban transition in the city of bordeaux 23 color culture and science journal vol. 12 (1) doi: 10.23738/ccsj.120102 material over time, especially its weather resistance. meanwhile, the loggias are painted yellow. by its very nature, paintwork requires maintenance. it is much less long lasting and is therefore easier and less costly to change over time. according to van doesburg’s definition (1924), the yellow on this façade is a decorative color, a means of decorating the surface, as a simple addition or ornamentation; the gray, however, is a plastic color as it becomes a material of expression and has “a value equivalent to all materials such as stone, iron, glass.” 4. conclusion this analysis of some urban and architectural examples shows that in a unesco world heritage city the use of color in architecture is associated as much with the architect’s position and reputation, as with the building’s location in the city or its function. designers opting for color in architecture often feel the need to justify and rationalize their choice, in particular by focusing on the existing environment. yet the color choice is usually influenced by subjectivity and hence by the architect’s own taste, or the tastes of other players in the city who intervene at different stages of the project. colored buildings may be few and far between in the city of stone, but they are often to be found in places of urban divide between two landscapes. the further we move from the historic center, the more colored buildings we come across. color is also used to identify a building, to distinguish it from others, to allow its appropriation by adopting shades that are thought to be appreciated by the citizens concerned. in any case, colors seem to be complex to manage (servantie 2007). nevertheless, by determining the predominant colors and identities of a place it is possible to focus a project more precisely, thus making it easier for residents to appropriate the space. in the case of bordeaux, it seems that the acceptance of a colored building depends of its level of adaptation regarding the territory concerned more than the use of a common reglementation for all the city. 5. conflict of interest declaration the authors declare that nothing affected their objectivity or independence and original work. therefore, no conflict of interest exists. 6. funding source declaration this research did not receive any specific grant from funding agencies in the public or not-for profit sectors. 7. acknowledgment the authors wish to thank chantal callais and thierry jeanmonod, who initiated this study, as well as the architects who agreed to answer our questions, allowing us to collect the data needed to finalize this work. 8. short biography of the authors aline barlet environmental psychologist, phd psychology behavioural sciences and social practices, master degree of architectural and urban acoustic. codirector of the greccau laboratory, associate professor at bordeaux higher national school of architecture and landscape architecture, france (ensap bordeaux). the research and teaching topics are sustainability issue, comfort and atmospheres and particularly in the fields of territorial consultation, energetic and environmental transition. audrey bousigues architect. master degree of ambiances and comfort for architectural and urban design. alice herbert architect. master degree of ambiances and comfort for architectural and urban design. references barba, j. j. and peinado, i. (2017) le corbusier’s cité frugès: prototype city of workers in the 1920’s. metalocus, 8 october 2017, https://www.metalocus.es/en/news/le-corbusiers-cite-fruges-prototypecity-workers-1920s. (accessed: 16 december 2019). callais, c. and jeanmonod t. (2017) bordeaux, la fabrique d’un patrimoine: paysages d’une ‘cité historique vivante’. bordeaux: ensapbx. charnay, y. (2017) ‘paris, une ville lumineuse aux couleurs discrètes,’ environmental colour design: theory and practice, schindler, v. m. and griber y. a. (eds.) social transformations, 27, smolensk: smolensk state university publishing house, pp. 37–49. costedoat, d. (2007) hôtel seeko’o, atelier d’architecture king kong. bordeaux: overworld. déribéré, m. (1964) la couleur. paris: presses universitaires de france. cité du vin (2016) available at: www.laciteduvin.com/fr/explorez-la-citedu-vin/architecture/edifice (accessed: 12 december 2016). lenclos, j. p. and lenclos d. (1982) les couleurs de la france: maisons et paysages. paris: le moniteur. loos, a. (1913) ‘ornement et crime.’ les cahiers d’aujourd’hui, 5, pp. 247–256. color as a sign of urban transition in the city of bordeaux 24 color culture and science journal vol. 12 (1) doi: 10.23738/ccsj.120102 lynch, k. (1960) the image of the city. cambridge, ma: massachusetts institute of technology press. noury, l. (2008) la couleur dans la ville. paris: le moniteur. ruskin, j. (1880) the seven lamps of architecture. mineola ny: dover publications. servantie, m. p. (2007) chromo-architecture: l’art de construire en couleur. paris: alternatives. soulié, l. (1988) ‘contre les rues supermarchés.’ parinaud, a. (ed.) la couleur et la nature dans la ville: murs peints, sols, fontaine’ paris: editions du moniteur. unesco. recommendations on the historic urban landscape (2011) records of the general conference 36th session, vol. 1. paris: unesco, pp. 57–62. van doesburg, t. (1924) ‘la signification de la couleur en architecture.’ la cité, 4(10), pp. 181–187. 89 color culture and science journal vol. 12 (2) book review: l'anima e la magia dei colori. uso consapevole dei colori nella vita renata pompas samya ilaria di donato: l'anima e la magia dei colori. uso consapevole dei colori nella vita. le due torri, bologna, 2017. samya ilaria di donato is a colour researcher and consultant. previously a country manager for a multinational company and president of the italian association of image consultants, careers that she left (after a health problem which changed her existential perspective) to dedicate herself entirely to colour. today she organises colour training and consultancy for leading companies, is a business counsellor, trainer in chromodisciplines, talent consultant as well as creator of colourrelated events. of her many publications, i started with this book l'anima e la magia dei colori and it allowed me to gain an overview of her research, to be explored more deeply in the other texts. it is a particular and unusual approach, based on diverse spiritual and holistic disciplines and, as the author explains, it is divided into four levels: physical, mental, emotional and spiritual. in the introduction, the relationships established between the source, the object and the observer as well as their influence on the body are examined. then di donato looks at the significance and function of colours through myths, rituals, alchemy, and holistic therapies, with the aim of evoking a "journey" of knowledge. the significance of colours represents the main aspects. alchemy myth or a real pre-chemistry discipline that has fascinated scientists like isaac newton, and philosophers like john locke and whom psychoanalysts such as carl jung and james hillman have written about describes the different corresponding colours of nigredo (the blackening or melanosis), albedo (the whitening or leucosis), citrinitas (the yellowing or xanthosis) and rubedo (the reddening, purpling, or iosis) which mark the different phases necessary to achieve philosophical gold. religion illustrates how different religious denominations use colours to express mystical notions of which i list a few examples. in addition to the traditional colours of the castes (varna = colour), hinduism explores the seven "chakras" (energy centres) with their seven colours each one connected to meaning, an element, a function, a planet marking the path to asceticism. the author explains judaism’s ten "sĕfirōt" (emanations through which the divine is manifested, also connected to the practical and emotional circumstances experienced by each individual in daily life) with their colours and features. from christianity, she examines the liturgical colours together with those of the archangels whose colours symbolise the functions. buddhism's five primary colours ("pancha-varna") are also discussed. so-called "natural" chromotherapy provides a concise overview: chromotherapy, which uses colours to restore the body's balance. crystal therapy uses crystals, stones and minerals of varied shapes and colours for the same purpose. the family constellations, which apply the colours of the "chakras" to the systems psychology technique devised by german psychologist bert hellinger. art therapy, which cures several psychological disorders through drawing and colouring. ayurveda (the science of longevity) expresses its three "doshas" (vital energies) with colours. aura soma which heals through contact with coloured bottles filled with an infusion of herbs, essential oils, plant extracts, buds, crystals and water. reiki, the japanese practice that conveys healing energies through the placing of hands, applied by the author using the colours of the "chakras". beyond the discussion on the science and effectiveness of these practices (around which there is a debate which is not appropriate to mention in this context) i thought it was very interesting to see how they all turn to colour as both diagnosis and cure, as well as all the myths, rites, religious confessions, esoteric practices that the author describes zodiac signs, tarot cards, enneagram, etc. all of which are not only a question of science and efficacy. signs, tarots, enneagram, etc., which give the colour symbolic, signifying, active and transformative properties. 90 color culture and science journal vol. 11 (2) in conclusion di donato in the twelve chapters of the book presents a wide and diverse outline of the various fields of knowledge in which colour is the protagonist, quick and essential points in which the content stirs the comparison between cultures and applications, searching for similarities and differences. for more information: https://samyadeicolori.it/. cultura e scienza del colore color culture and science 44 cultura e scienza del colore color culture and science | 02/14 larger differences give a lower number. if the test light’s cct is lower than 5000 k, the reference light source of equal correlated color temperature (cct), is selected within the planckian’s radiator group, otherwise from illuminants of d-series (which should approximate the spectrum of natural light in several hours of the day). the r a value, usually provided by the manufacturers, represents the average of the indexes r i of the first 8 samples. the cie publication 177 (published in 2007) reports the results of some perceptive experiments and of the simulation on the color rendering: on the basis of those experiences, the technical committee cie tc 1-62 of division 1, “vision and colour”, has established that the color rendering index cie cri is not generally applicable to establish the color rendering rank order of a set of light sources when white led light sources are involved in this set. [2]. also, the calculation of the cri was designed many years ago, according to sources with continuous and regular spectrum. with the leds is now possible to create light sources that have a wide variety of different light spectra. one can create a light source that matches very well only the color samples of munsell system used for calculating the cri, thus obtaining a high cri, although for other colors the color rendering can instead be very low. this recommendation is based on a survey of numerous academic studies that considered three different type light sources: phosphorcoated white light leds, red-green-blue (rgb) led clusters and traditional lamps (fluorescent). most of these investigations involved visual experiments where observers ranked the appearance of illuminated scenes (containing real object or color samples) using lamps with different cris. on the basis of result obtained, in general, we can say that there was poor correlation between these rankings and the order produced through the calculated cri values. in fact, many rgb-based led sources show low values of r a index, yet the objects appearance is reported to be acceptable by the observers. all the new proposed indices fall in one of three basic categories of color rendition: • the accurate rendition of color as they appear if they would be lighted under a reference light source (color fidelity index) 1. introduction the solid-state lighting (ssl) has now reached considerable efficiencies that make it suitable for different applications, from general office lighting, retail spaces, without forgetting the possible applications in the domestic sector. the led technology has already satisfied the demands of the market and the lighting’s designers concerning luminous flux and efficiencies and now the new challenge is represented by the color quality of the emitted light. the new technologies have provided the opportunity for manufacturers to customize different aspects of a lighting product: • the intensity distribution in photometric space • the spectral distribution both in terms of color temperature, and optimizing the color rendering in according to specific lighting application. the first question to answer is if there are any appropriate instruments for the assessment of the chromatic color rendering, which can be also applicable to new solid state lighting source. in general we can say that the color rendering index represents the ability of a light source to reproduce the colors of various objects in comparison with a natural or ideal source. the international commission on illumination (cie), has defined the color rendering index as the effect of lighting on the chromatic appearance of objects (in a conscious or unconscious way) rather than the chromatic appearance under an illuminant reference [1]. the latest (and currently in force) version of cri (color rendering index) follows cie’s proposed method and it is described in the 1995 publication 13.3, “method of measuring and specifying color rendering properties of light sources”. the cie color rendering index is based on the direct comparison of a set of eight color samples, each illuminated by two sources, the first one is the light source under test and the second is the reference with equal correlated color temperature. the test procedure involves comparing the appearance of eight color under the tested light and a reference light source. the average differences measured are subtracted from 100 to get the cri. using this method, small average differences will result in a higher score, while fulvio musante, fulvio.musante@polimi.it maurizio rossi, maurizio.rossi@polimi.it dipartimento di design politecnico di milano an overview for colour rendering indices in solid state lighting 4502/14 | cultura e scienza del colore color culture and science test source cct step 2 reference illuminant step 5: chrom. adapt. x, y, z x, y, z u*, v*, w* u*, v*, w* step 3: test samples step 7: ∆e i ra,ri step 4: step 6: step 1: figure 1 workflow for calculation the color rendering index r a , defined by the cie publication 13.3 (1995) • the light source ability of rendition of objects appearance like if they appear “vivid”, ”pleasant”, or ”flattering” (color preference index) • the ability of light source to allow an observer to distinguish colored parches when they are viewed simultaneously (we reference to this dimension of color rending as “color discrimination”) each color rendering index proposed in scientific literature can be classified into one of the three categories: the particular application should suggest the proper color rendering characteristic that a lighting design project is called to meet and consequently the designer must choose the most appropriate rendering index for the evaluation of the light sources used. 2. update cie color rendering index the cie standard method has some defects and shortcomings: • reference illuminant: the choice is between black body radiator and daylight phase of the same cct as the test source. however, there is no evidence that these reference illuminant is the most optimum source in terms of naturalness and other subjective aspect of color quality [7][8]. furthermore, no source can render the colors better than the reference, a situation that represents a limit to the development of new sources. • the set of used samples (8 desaturated color + 6 saturated samples) were extracted from the munsell’s atlas, but are no longer commercially available. in addition, selected samples do not cover the gamut of possible colors in proper manner as instead can make color samples extracts from other collections like macbeth colour checker. davis and ohno show that a light source can perform well with the standard eight color sample (desaturated) employed for calculation of actual cie rendering index, 46 cultura e scienza del colore color culture and science | 02/14 but the same source perform poorly when used in connection with saturated color sample. the same authors, show that the contrary (better result with saturated sample and poor results with desaturated ones) is never true [9]. • the used formula to take into account chromatic adaptation in illuminant change (switching from a sample lighted by reference lamp to a new situation where the same samples are now lighted by test lamp) has proved to be inapplicable for large chromatic differences. • the color space u*, v*, w* is not figure 2 cqs color sample perceptually uniform in relation to other color spaces defined more recently by cie, and even the suggested mathematical relation for color difference evaluation appears to be obsolete and inadequate. • the use of a single value average, fails to explain the differences in color rendering of two different sources that have the same general index value, but different values in the special color rendering index (r i ). • some researcher expressed a preference that the special color rendering index should not go below figure 3 gamut area in cielab color space: in red test lamp, in blue reference lamp. 4702/14 | cultura e scienza del colore color culture and science the zero: the main idea is that a scale between 0 and 100 would be less confusing for non-expert users[9], even if there isn’t a special meaning associated with the zero value. for some type of discharge lamps, such as low pressure sodium, the value color rendering index r a is negative and thus difficult to understand for non-expert users. the national institute of standards and technology (nist)[9] developed cqs (color quality scale): like r a , cqs is based on the comparison to a reference illuminant with the same cct. qcs is a new color rendering metric qa that updates cri r a in several aspects: • better chromatic adaptation model (cmccat2000)[18] • a new set of 15 saturated test color sample were chosen • illuminants are not penalized for increase of chroma • the more up-to-date cie l*a*b* uniform color space is used to measure the color shift between the test illuminant and reference illuminant • colour differences for each sample are not simply averaged as in cie r a , but they are combined by root mean square: all 15 test color samples are used to evaluate the general cqs score through a weighted root mean square (rms) approach for better statistical properties • the light sources that show a very low correlated color temperature are penalized because they have a small gamut area (introduction of cct factor) • a scaling factor is introduced so that the 12 reference fluorescent lamps have the same score using cqs metric or r a • cqs values are in the range from 0 (very poor color) to 100 (perfect color): a sigmoid function is introduced to translate negative values (of special indexes) to low values (below 20) different formulation of this index is proposed by the author. seven of the 15 test-color sample have been changed during the evolution of indices, cct factor was removed, in the last version q f (gamut area index) is evaluated on the base of reference illuminant with equal cct. in this index several sub-indices were be proposed, in order to do a proper evaluation of different aspect of color rendering problem: • q g : evaluated as relative gamut area formed by (a*,b*) coordinates of the 15 color samples in cielab space normalized to a gamut area of a reference illuminant at the same cct and multiplied by 100. the value of q g could be greater than 100 and the last version of the method doesn’t employ any chromatic adaptation transformation. the first version of this index used a fixed reference illuminant d65. • q f computed by the same scheme of qa, except the exclusion of saturation factor: it is a pure fidelity index, in similar way to r a . the result is scaled between 0 and 100 so that reference fluorescent lamp have equivalent value of q f and r a . a promising candidate for substitution of cie color rendering index is proposed by k. smet et al [14]: it is a color fidelity index and it is based on the previous work and experience of numerous working group inside tc-169, the cie technical committee dealing with color rendition of white led light source. the computational structure is similar to traditional cie r a index, but same of important improvements are proposed to overcome weaknesses and problems listed above. this rendering index, called cri2012 (previously called ncri) is a color difference metric that presents the following major feature: • the outdate color space for color shift evaluation and chromatic adaptation transformation are replaced by color appearance model ciecam02/cam02ucs[10][11]. • averaging of partial indices and linear scale are replaced by rms (root mean square) and by a nonlinear function which tends to saturate the limits of intensity range: this behavior should better reflect the features of human perceptual response. • a new scale factor is introduced so that standard cie illuminants f1 to f12 have the same average value using ra metric and r a 2012 . • the previous set of 14 color samples are changed in two different way: the standard eight samples, used for r a calculation, are replaced by an imaginary (mathematically defined) set of color samples; the special color index are replaced by a set of 210 real reflectance function, characterized by low and high color constancy, so it is possible to obtain detailed hue-specific information (the set should properly sample the entire gamut volume). • the reference illuminant is selected through the same rule adopted for r a : blackbody radiator for test source with 48 cultura e scienza del colore color culture and science | 02/14 cct below 5000 k, daylight illuminant for others. • the test sample chromaticity is now evaluated by cie 10° standard colorimetric observer because of wellknown inaccuracy of cie 2° standard colorimetric observer in the blue region of visible spectrum. the influence of the spectra of test samples on the calculated color rendering index is a long time open question: due to a small number of samples, lamps manufacturers are able to tailor the light sources spectral distribution to yield high cri value, even if the visual impression of color rendering is considered poor[12][13]. in particular, tri-phosphor fluorescent lamp (warm white) is overrated by the current formulation of rendering index as suggested by the visual experiment. the inadequacy of the current set of test colors is shown by the observation that special rendering index ri changes if a near metameric test sample are used in calculation instead of original set [14]. 3.two metric approach the main idea is that only one number can’t include the multidimensional problem of color rendition, but on the other hand lighting industry and designers need simple and clear tool to evaluate the color rendering of light sources. another interesting method for evaluating color rendering performance of ssl source, is to use a two-metric approach that combines cri and gai (for gamut area index) [19]. index based on gamut area evaluation has been used as a predictor of user’s preference or color discrimination, but it’s an imperfect solution for both features. in case of preference, for example, too large gamut area makes object color too saturated so they appear unnatural and not preferred [15] [16]. in case of color discrimination, the increase of saturation, which leads from large gamut area, is sometimes followed by hue shift of several sample (even in this case, if the color distortion is too high, then the user’s preference will be very low)[9]. gamut area index (gai) uses the same eight test color samples as cri: the index is based on evaluation of the polygon’s area (called “gamut area”) described by eight test color samples in the cie u’v’ color space. to calculate the gai value, the gamut area of the test color samples is compared to that of an equal energy spectrum source. a gai score of 100 means that the gamut area is of the same size as the equal energy source: a light source with a good cri score and a good gai score (between 80 and 100) is considered to have good “color fidelity” and “color vividness” . a light source with a low gai score produces poor rendering on saturated colors, whereas a large gai score indicates an overly saturated rendering. rea and freyssinier-nova suggest numerical recommendations about the value of gai index: if the applications (for example retail) require high features for color rendering, the light source should have both ra of between 80 and 100 and gai between 80 and 100.[3][4] an important notice is that in gai, the evaluation of the correlated color temperature of reference light source is fixed and independent from that of the source under test: this solution can involve distortions in the judgment of the light sources with low values of correlated color temperature that can still have excellent color quality including good color discrimination performance, despite the low value of the gamut area. recent research suggests that the lighting designer community should develop a twometric system for color rendering of light source: the idea is the combination of an index representing the color fidelity aspects with a measurement of gamut [5]. experts can manage multiple index without any kind of problem, but for other users it’s still necessary to summarize the information into a limited number of measures: when two measures are used, there is enough information in relation to lighting design applications. the proposal considers a color fidelity based index (we can have information about the fidelity of light source in rendering a set of color sample in comparison to a reference lamp whit the same cct) and a measure connected with the gamut area evaluation. houser et al. suggest that the couple of indices to be considered are q a and q g , where q a is the fidelity component and q g is the gamut area evaluation. for houser et al. the color fidelity component should not be a pure fidelity index as suggested by other researcher previously[6]: this kind of metrics penalize all color shift and may incorrectly penalize illuminants that favorably increase the chroma (for this reason the proposal is q a index). even traditional gamut measures (gai) present the same problem because of their dependence upon cct: the proposed metrics is q g because it’s an existing measure of relative gamut and because shares some computation features with q a , such as color sample. 4902/14 | cultura e scienza del colore color culture and science 4. conclusion the color rendering of the sources in solid state lighting is a very complex problem which has to take in account different requirements and constraint. it is possible that in the future there will be different types of indices, depending on the applications that the lighting designers have to face: in any case it seems that the solution of the problem will be proposed shortly. the approach through the use of two metrics seems to offer greater flexibility and completeness, but only a perceptual experiment can fully assess the effectiveness of this solution. a simple word scale has the capability to capture overall color quality of a light source and it would be especially useful for end-users to proper rate a solid state light source in comparison to others. bodrogi et al., developed a formula (based on series of visual experiment carried out with a color similarity judgment task on ordinal rating scales, as well as on interval rating scale labeled by categories of color similarity) to predict a category of color similarity from an instrumentally measured color difference: this formula was applied to interpret the values of the new colour rendering index (cri2012) in terms of semantic categories taken for everyday language (excellent, very good, good, moderate, low, bad, very bad)[17]. this solution enable end-users and lighting designers to understand the metric values of cri2012, and the importance of difference of different magnitude inside the cri2012 scale index. if the assessment of color rendering (for reasons of simplicity and tradition) must be reduced to a single number, the sophisticated models used in the most recent versions of the index, will end up providing to the end users the same level of knowledge of the previous indices and the latter improvements introduced, will become marginal. bibliography [1] cie 1987, cie international lighting vocabulary, international electro technical vocabulary chapter 845: lighting, cie 17.4 cei pub.50(845) sec. 845-03. [2] cie 177:2007 “colour rendering of white led sources”, chapter 3.2. [3] m. s. rea, “a practical and predictive two-metric system for characterizing the color rendering properties of light sources used for architectural applications,” in proc. of spie-osa vol. 7652. international optical design conference 2010, 765206–1 – 765206–7. [4] m. s. rea and j. p. freyssinier, “color rendering: beyond pride and prejudice,” color res. appl. 35(6), 401– 409 (2010). [5] kevin w. houser, minchen wei, aurélien david,michael r. krames and xiangyou sharon shen, review of measures for light-source color rendition and considerations for a two-measure system for characterizing color rendition, optics express, vol. 21, issue 8, pp. 10393-10411 (2013) [6] p. van der burgt and j. van kemenade, “about color rendition of light sources: the balance between simplicity and accuracy,” color res. appl. 35(2), 85–93 (2010). [7] smet k, ryckaert wr, pointer mr, deconinck g, hanselaer p. correlation between color quality metric predictions and visual appreciation of light sources. optics express 2011; 19: 8151–8166. [8] smet kag, ryckaert wr, pointer mr, deconinck g, hanselaer p. a memory colour quality metric for white light sources. energy and buildings 2012; 49: 216–225. [9] w. davis and y. ohno, “color quality scale,” opt. eng. 49(3), 033602 (2010). [10] c. li, m.r. luo, b. rigg, and r.w.g. hunt, cmc 2000 chromatic adaptation transform: cmccat2000,color res. appl. 27(1), 49–58 (2002). [11] cie tc 8-01 (2004). a color appearance model for color management systems. publication 159. vienna: cie central bureau. isbn 3-901906-29-0. [12] smet k, ryckaert wr, pointer mr, deconinck g, hanselaer p. correlation between color quality metric predictions and visual appreciation of light sources. optics express 2011; 19: 8151–8166. [13] sandor n, schanda j. visual colour rendering based on colour difference evaluation. lighting research and technology 2006; 38: 225–239. [14] k. a.g. smet, j. schanda, l. whitehead and r. m. luo, cri2012: a proposal for updating the cie colour rendering index, lighting res. technol. 2012; 0: 1–21 [15] d. b. judd, “a flattery index for artificial illuminants,” illum. eng. (usa) 62, 593–598 (1967). [16] w. a. thornton, “a validation of the color-preference index,” j. illum. eng. soc. 4(1), 48–52 (1974). [17] bodrogi, p., brückner, s., krause, n. and khanh, t. q. (2013), semantic interpretation of color differences and color-rendering indices. color res. appl.. doi: 10.1002/ col.21798 [18] li cj, luo mr, hunt rwg. a revision of the ciecam97s model. color res appl 2000;25:260 –266. [19] m. s. rea and j. p. freyssinier-nova, “color rendering: a tale of two metrics,” color res. appl. 33(3), 192–202 (2008). 43 color culture and science journal vol. 11 (2) doi: 10.23738/ccsj.110205 education about colour: a look at some authors from the 19th and 20th centuries in italy: corrado ricci, maria montessori and giuseppina pizzigoni franca zuccoli1 1 department of human sciences for education, university of milano-bicocca, milan, italy corresponding author: franca.zuccoli@unimib.it abstract in this contribution, the aim is to juxtapose three figures who, in spite of their very different skills, were interested in the element of colour. the first is corrado ricci, an illustrious art critic and historian, who started to study children’s drawings at the end of the 1800s, making him one of the first in italy to do so. in 1877, he published a small pamphlet called l'arte dei bambini (the art of children), which included a special reflection about the theme of colour. conversely, the other two authors are pedagogists: maria montessori (1870–1952), an internationally renowned figure who also dealt with the theme of colour through her method, equipment and tools, and giuseppina pizzigoni (1870–1947), a pedagogist who dedicated positivist attention to the theme of colour, which she linked to natural aspects and a connection to the vegetable garden, a cornerstone of her method. at the end of this historical overview, a survey that was conducted by the istituto comprensivo rinnovata pizzigoni is presented, in an attempt to observe the colour-related proposals that have been made. keywords: colour, education, children, school, pedagogy, montessori, pizzigoni received 30 may 2019; revised 15 june 2019; accepted 25 june 2019 education about colour: a look at some authors from the 19th and 20th centuries in italy: corrado ricci, maria montessori and giuseppina pizzigoni 44 color culture and science journal vol. 11 (2) doi: 10.23738/ccsj.110205 1. introduction interest in children’s drawing and their use of colour is a research theme that has been observed in a systematic manner since the early 20th century. re-examining how certain italian authors have tackled this theme, as pioneers, is a significant concept, because it allows us to examine the idea of a child beyond the cultural context, as well as their potential. it is from this that the educational proposals formed are directly derived. the choice of authors, who certainly belong to a much wider overview, stemmed from a careful research for those who had mentioned the theme of colour in their writings. without doubt, the first was corrado ricci (1858–1934), who established himself as the pioneer in the study of children’s drawings and helped to separate these from the idea of incompetent attempts. on the other hand, the other two figures – maria montessori (1870–1953) and giuseppina pizzigoni (1870–1947) – allow us to see how pedagogical declination supports the proposed actions, moving them towards different paradigms that are always linked to the theme of colour. 2. corrado ricci and his interest in children’s drawings corrado ricci’s focus on children’s drawings and the use of colour is an important action, one that is revolutionary compared to many scholars from that period. firstly, we must outline his background. ricci was a writer, an art historian, a general director of fine arts and antiquities and a scholar of s. luca. it was an accident that led him to study children’s drawings, even if his eyes were certainly trained and attentive towards the various forms of artistic expression. in his book l’arte dei bambini, he recounts the episode that gave rise to his new-found interest. this is what he tells us: “one day in the winter of 1882–83, as i was returning from the certosa di bologna, i was caught in the rain and forced to shelter under the portico […]. i did not know that there was a permanent literary and artistic exhibition beneath these arches, which was of little aesthetic value […]. the sadness of that day […] reconciled me with the clever art of children and gave me the idea for this study.” (ricci 2007). this new focus pushed ricci to observe the works of children: to collect them, catalogue them and study them. the assistance provided by raffaele belluzzi, multiple masters and adolfo venturi, an art historian, was fundamental, however, in achieving this goal. it was the latter who collected 250 children’s drawings or had them collected. this small pamphlet was the result of these careful studies of children’s works, which experienced growing success, as well as quick and constant dissemination over time, even crossing beyond italy’s borders. ricci underlines the push of children towards creating drawings. these are experienced as creative projects, even if they are imperfect and have specific characteristics, which manage to overcome mere imitation and reveal the presence of stadial steps. the key words highlighted by ricci as specific features that appear in many of the children’s works studied are: transparency, integrity, integral version. these are seen as direct evidence of a growth process that proceeds on a trial-and-error basis, by trying to overcome the many problems that are inevitably caused by representing some on a two-dimensional surface, combined with an inevitable lack of graphic experience and a strange outlook on the world. ricci’s work also received a lot of recognition from overseas. what is still striking to this day is the decision to dedicate attention towards children’s drawings, which many scholars at the time considered to be an imprecise and imperfect product that did not warrant being studied. within ricci’s writing, there is a paragraph called il bimbo e il colore (the child and colour). the author highlights that previous scholars, such as hugo magnus and gladstone, who based their works on readings of homer or hypothetical scientific experiments, stated that people in the past saw only a few colours. this idea, however, was not limited to people in antiquity: “it is helpful to note, however, that this colour blindness was attributed to populations in antiquity, savages and children.” (ricci, 2007) by looking into the various hypotheses, ricci comes to state that: “in terms of savages, repeated and scrupulous experiences have demonstrated that their sense of colour was in no way defective. all that is left for me to discuss is children.” (ibid.) he quotes preyer, who stated that children first saw yellow and red and, only later, green and blue, which was otherwise confused with grey. for ricci, it was easy to dismantle this hypothesis, by highlighting the reason for this lack of ability to distinguish as being not a visual difficulty or limitation, but rather a circumscribed development of the appropriate language. “their pictorial lexicon is very limited, and, in terms of art, they mostly do not use the various derivations for the term “painter” as someone who paints; the act of drawing and colouring, to them, is referred to as “painting”. […] imagine, then, if one could acquire the phraseology of the chromatic scale! in fact, after performing experiments with 306 children, bono concluded by saying that the illusion of colour blindness in children – just like in savages and people in antiquarian times – stemmed from the lack of language and is a false comparison.” (ricci 2007) however, this statement was not intended to say that children should be left alone on their journey to explore and discover: “there is certainly a need to educate education about colour: a look at some authors from the 19th and 20th centuries in italy: corrado ricci, maria montessori and giuseppina pizzigoni 45 color culture and science journal vol. 11 (2) doi: 10.23738/ccsj.110205 children’s sense of colour, as they educate their own drawing skills. this is not because it is accurate that they do not see colours, but because they discover a reasonably harmonious response to what is. this is because, in the same way that they see things well but do not know how to depict them with signs, they see colours well and do not know, or care, about finding them in their palette. the various gradations and the semi-tones of the shades reach the retinas of their eyes, but not their artistic intelligence, and are generally satisfied with bright colours that are close to what is true.” (ricci 2007) the advice given to teachers and parents is to encourage the children’s attention to what they naturally observe, thus strengthening their accuracy in reproducing it and, in particular, identify the various tones in the shades. in concluding his text, ricci states that the child reproduces the object by following what their memory suggests, later passing to a more exact observation, due to the expansion of their knowledge and skills that is stimulated by education. 3. maria montessori and colour by passing from an author like corrado ricci, an art historian, to a profoundly different figure like maria montessori, we can discover a different relationship with the theme of colour. a doctor and pedagogist, she was extremely passionate about the life of children – in particular, disadvantaged children – and also interested in children's relationship with colour. it must be immediately stated that montessori, when designing specific didactics for her method, and dealing with this theme, did not only study the childhood use of colour in graphic depictions, but considered a global approach that involved the physical, emotional and cognitive aspects of the child. for the sake of simplicity in this argument, we can argue that her attention focused on different perspectives; for this brief analysis, at least four can be highlighted: 1 – the creation of educational-scholastic environments; 2 – the design and identification of scholastic/developmental materials; 3 – artistic education; 4 – physical-health checks and sensory education, from the perspective of visual distinctions. in order to confront these points, we will use phrases written by the author herself, as we have done for the previous author. in this case, these are taken from a variety of texts, in an attempt to create an overview, the focus of which will always remain colour. for the first and second point, one recalls that the environment and materials are fundamental elements in the montessori method. in fact, they guide the child, promoting independence facilitating constant control over the error, without the need for the teacher’s presence to be pervasive. “it is not only objects for sensory education and culture, but the entire environment that is prepared to make error control easy. the objects, from the furniture to the individual development materials, act as denouncers, whose calming voices cannot be escaped. the bright colours and shimmer denounce the stains […] and each child hears the guidance as if they were alone with the inanimate teacher” (montessori 2013). specifically, the objects must be designed with specific characteristics, with the idea of their learning objective not confusing too many qualities. the words of montessori point to this specific idea: “the isolation of a unique quality in the material. any object that we want to use for sensory education will present, by necessity, many different qualities, such as weight, texture, colour, shape, dimension, etc. it is necessary to isolate a single quality of the object from among the many. […] if one wishes to prepare objects that serve, for example, to distinguish between colours, it is necessary to build them with the same substance, form and dimension and differentiate them only by colour” (montessori 2013). another fundamental aspect for the proposed objects – though not only these – is linked to aesthetics. “aesthetics – another characteristic of objects is to be attractive. the colour, shimmer and harmony of the shapes are things that are considered in everything a child is surrounded with” (montessori 2013). the objects, which are designed according to the characteristics outlined above, have a voice that is so intriguing that it attracts children: “the voice of things. it is true that the teacher supervises, but various kinds of things “call” to children of various ages. the shimmer, colours and beauty of beautiful, adorned items are the “voices” that capture children’s attention and stimulate them into action” (montessori 2013). this shows us how the presence of the colour element, when it is suitably considered and included, can act as an incentive to facilitate children’s work. when comparing environments and architecture, it is useful to remember the first experience of the “casa dei bambini” on via dei marsi, 58, in the san lorenzo neighbourhood of rome; this was inaugurated on 6 january 1907. “talamo’s wonderful idea was to gather young children who lived in the house, aged between 3 and 7 years old, and to bring them together in a room under the direction of a teacher, who also lived in that home” (montessori 1909). education was visually manifested in the care provided for the furnishings, the size of the child, the layout of the environment, for which education about colour: a look at some authors from the 19th and 20th centuries in italy: corrado ricci, maria montessori and giuseppina pizzigoni 46 color culture and science journal vol. 11 (2) doi: 10.23738/ccsj.110205 the same young people became the first caretakers. here, the choice of colours became a characterising element. in terms of the third point, which relates to artistic education, the pedagogist moves away from the proposal of free drawing, which had become popular in those years. “so-called free drawing does not come into my method: i avoid the immature, unnecessarily exhausting tests and scary drawings that are in vogue in modern schools with advanced ideas” (montessori 2013). a few pages later, she notes: “in conclusion, the best way to influence drawing is not to let it be free, but to prepare natural ways to produce it, that is, to train the hand” (montessori 2013). in her observation about drawing, her attention is instead focused on two fundamental elements that she has identified, for which she proposes a series of exercises that aim to train the hand and the eye. “there are various elements in drawing, such as outlines and colours. for these two elements, we can now trace the outlines of the joints and fill in the drawings with lines; this prepares the hand for a secure muscular exercise. for colours, we provide brushes and watercolours, with which one can create drawings, even when the outlines have not been prepared. we also provide pastels and demonstrate how they can be used. finally, it is possible to create artistic representations by cutting out coloured pieces of paper, such as those which oswald, the famous vienna-born physicist, prepared for artistic purposes. these pieces of paper, which are finely gradated in terms of colour and scientifically prepared, lend themselves to the appreciation of the harmony of colour combinations. these two separate elements – lines and colours – are determined and perfected independently of each other. these are acquired by the individual, who becomes capable of expressing themselves artistically using the two elements together” (montessori 2013). specifically for the fourth point of this discussion, which deals with visual and auditory distinctions, montessori provides a specific material for colours, which she calls colour materials: “the material that leads to colour recognition (education of the chromatic sense) is as follows, which i have established after a long series of trials on regular children. […] the definitive material consists of tablets that have brightly coloured silk threads around them [...]. i chose nine shades, with each corresponding to seven gradations of differing intensities: therefore, there are 63 colour tablets. the shades are: grey (from black to white); red; orange; yellow; green; turquoise; purple; brown; pink” (montessori 2013). in another text, il segreto dell’infanzia (the secret of childhood), she recounts a small episode, which begins a reflection on children’s skills regarding colours. a teacher, who was experimenting, with much difficulty, with the method, was unsuccessful in delegating control of the materials to the children, as predicted. the culmination involved the coloured tablets: “one day, though, the box, which contained almost 80 tablets with different gradated colours, fell from the teacher’s hands. i remember her embarrassment, because it was difficult to recognise so many colour gradations. the children, however, ran over and, much to our surprise, quickly put all the gradations back into place, showing that they have a wonderful sensitivity to colours, even greater than our own” (montessori 2017). this subtle ability to distinguish, which is found in children, completely changes the idea of inability that, only a few decades before, in the age of corrado ricci, had been hypothesised. it recognises that children have an excellent level of focus, understanding and interpretation in terms of colour. some exercises were also planned within the field of physical and health checks, taking into account the correct growth of the child. “we must begin the process with very few contrasting stimuli, and then establish a number of similar objects that have an increasingly fine and imperceptible level of gradation. […] for the colours, one will choose the most bright and contrasting shades, such as red and yellow [...]. the final exercise, that of gradation, consists of putting similar but confusedly mixed objects in order of their gradation [...] the presentation of a series of yellow objects will be analogous, but the shade will gradate more clearly, from dark to bright. […] said objects must be arranged beside each other, according to the place that their quality establishes in the gradation” (montessori 2013). in conclusion to what has just been outlined, we can state that montessori was one of the first scholars to dedicate in-depth attention to the relationship between children and colours, its potential to act as content to be proposed and as a possible factor to positively influence learning skills, by using it as both a didactic tool and in scholastic environments and as a subject in various disciplinary fields. 4. giuseppina pizzigoni and colour giuseppina pizzigoni, a milanese pedagogist, had a different outlook. she created a method based on science, direct and personal experience and the didactic use of the vegetable garden as a focal point for all educational activities. for her, examining the theme of colour occurs through a scientific outlook. in terms of life drawings to be taken from the outdoor world, the observation of trees in spacious courtyards and the various types and shades, these become living material that can also be reflected on in terms of colour. “i always begin teaching drawing from life drawing, not from a drawing that has already been education about colour: a look at some authors from the 19th and 20th centuries in italy: corrado ricci, maria montessori and giuseppina pizzigoni 47 color culture and science journal vol. 11 (2) doi: 10.23738/ccsj.110205 traced on the board or presented in models. from the very first class, i place the children in front of a bare tree and, after encouraging them to observe it, tell them to draw it. another time, i ask them to consider an evergreen plant, for example, a pine tree [...]” (pizzigoni 1971). this close observation is not limited only to drawing, but also covers many other disciplines, including italian. for example, here are some pages taken from a fifth-class diary, a tool for collective writing, which focuses on the specific offerings of nature: “7 october. how the plot from last year has been infested! some wheatgrass and gallant soldier are suffocating the strawberries and black nightshade and amaranth; it hides the salad and the beautiful green tufts of the sugar beets. we have observed that the flowers and the leaves from the black nightshade resemble the leaves and flowers of the tomatoes and the potatoes; in fact, all three belong to the solanaceae family” (pizzigoni 1971). this attention, which is accurate both scientifically and, at the same time, aesthetically, was also the base for the creation of said garden, which provided a series of colours, flowers and constantly different views, and allows children to constantly train their gaze on a panorama with natural colours that are in a constant state of renewal. the same interest that was shown for external spaces was also found in interiors. for these, she had designed a refined décor, tackling the criticism of those who believed this was without merit: “for this reason, the scuola rinnovata took care to prepare an artistic environment and the decorate the halls and corridors, the gym and the refectory with selected paintings that had a certain degree of gradation in terms of their relationship with the students’ powers of artistic comprehension” (pizzigoni 1956). the environment, observations and concrete actions of the children, then, are fundamental elements in training and informing children’s gaze and creative abilities, taking colour into consideration as a fundamental element. turning back to colour, a point in the chapter dedicated to drawing includes a small paragraph called “colouring”. here is what is written: “the use of colour plays a large role in drawing lessons; from primary school to the final class, colour has a role to play, even though it is achieved in various ways. this ranges from knowledge of the basic shades to the creation of shades and their gradation. this can be obtained with coloured pencils, pastels, watercolours and oil paints and special varnishes, the latter of which are effective for colouring toys. the colour is used to highlight the design of geometric figures and still-life drawings; furthermore, it brings animation to spontaneous design” (pizzigoni 1971). as we have been able to see with this pedagogist, colour is never an isolated proposal, but it is strongly implicated in the practice of investigating and discovery, pushing the conceptualisation process to a later step. it is a scientific, experimental colour and a necessary piece of data to carefully discover and explore nature and the world. 4.1. a look at the current situation staying within the framework of pizzigoni’s method, within the development course needed to become a teacher, which was organised in collaboration with the università di milano-bicocca and the istituto comprensivo rinnovata in 2018, a point that was dealt with in this process was linked to perception and the practice relating to colour within this school. after a continuous period of in-class training, the majority of people following the course noted the presence of many educational actions that involved colour, with a prevalence towards the use of colour pigment. their hypotheses for future activities, however, have been directed towards a rich and innovative range of possibilities, which are not limited to the specific field of image education, but are aimed at the relationships between colours and music, colours and science, colours and language. 5. conclusions this brief discussion – with its historic element – aimed to show how colour has also been a significant player in education programmes in the past. very different figures have studied it and proposed varied experiments and different uses. reading the texts of these relevant authors also suggests that colour is a field with thousands of possibilities, one that is interesting for teachers and educators today. a suggestion for young teachers is to reread some of these tests and launch small experiments based on recognised and codified activities; from that base, one can discover new processes with more innovative and interdisciplinary paths. 6. funding source declaration this research did not receive any specific grant from funding agencies in the public, commercial, or not-forprofit sector. 7. conflict of interest declaration the author discloses any actual or potential conflicts of interest including financial, personal or other relationships with other people or organisations within three years of beginning the submitted work that could inappropriately influence, or be perceived to influence, her work. 8. short biography of the author franca zuccoli – associate professor of pedagogy and special didactics. she teaches general didactics and image education in the department of humanities for education at the università di milano-bicocca. over the education about colour: a look at some authors from the 19th and 20th centuries in italy: corrado ricci, maria montessori and giuseppina pizzigoni 48 color culture and science journal vol. 11 (2) doi: 10.23738/ccsj.110205 years, she has collaborated with many museums and cultural heritage institutions, on educational and didactic projects. the theme of colour is one of the topics that she deals with in her research. references montessori, m. (2013) ‘la scoperta del bambino’, garzanti, milano. montessori, m. (2017) ‘il segreto dell’infanzia’, garzanti, milano. pizzigoni, g. (1971) ‘le mie lezioni ai maestri d’italia’, editrice la scuola, brescia. pizzigoni, g. (1956), ‘linee fondamentali e programmi e altri scritti’, editrice la scuola, brescia. ricci, c. (2007) ‘l’arte dei bambini’, armando, roma. cultura e scienza del colore color culture and science 14 cultura e scienza del colore color culture and science | 04/15 1walter arrighetti, phd walter.arrighetti@gmail.com 1cto | frame by frame italia motion picture colour science and film ‘look’: the maths behind aces 1.0 and colour grading 1. introduction one of the biggest colour-related problems for the film production and post-production industry is two-fold: to ensure that the creative “look” of video content, as envisioned by the cinematographer, is preserved throughout ([1]– [2]), and to be able to consistently reproduce this ([1], [3]). that also has to be independent both on digital cameras or computers generating and animating it (as input), and on finished asset specifications for the end-users to watch and enjoy it (as output) — be it either in a dark digital cinema theatre, at a home tv setting, or using a video-on-demand (vod) or internetstreaming application, in a day-lit room or even open sunlight. in recent years many proprietary/commercial tools and workflows emerged, each driven by specific, not always cross-compatible needs (e.g. on-set grading, digital cinema mastering, vod, etc.). this results in proliferation of a plethora of different formats vs. the scarce number of really interoperable standards. the author has put lots of efforts to provide a unified mathematical formalism and usability to most of the colour-management technologies used in the post-production world, both on independent publications and in collaboration with several entities in the business (like the smpte and the ampas). after a minimal introduction to such colour-mathematical terminology ([4]–[6]) and colorluts, two brand new colour-management techniques from highprofile moving-picture digital imaging (cdls and aces) will be described, as they aim at colour interoperability for the analysis and synthesis of digital ‘looks’, both on-set (production) and along the digital intermediate (di) phase. aces in particular, which the author has been active contributor to since 2012, is an academy-originated initiative for facilitating colour interoperability across the media & entertainment industry. 2. colour science mathematical formalist a gamut mapping between colour spaces ([5]– [7]) is a vector field l(c), where c∈g is the input colour in the source gamut g⊆irm (which is, to every practical aspects, a connected, linearly and superficially-connected m-dimensional domain—often even a convex one), with dim l(g )=n. let the input and output spaces be both rgb model (m=n=3) and their canonical bases be the left-handed triple {r,g,b}, so any input colour c∈ir3 is coordinated as c=rr+gg+bb and, for the input regular rgb cube, (r,g,b)∈[0,1]3. the output colour is thus l(c)=rr+gg+bb; by the hodge-helmholtz’ theorem, the orthogonal decomposition holds ([4]–[5]): where t(c) and h(c) are the conservative (curl-free) and the solenoidal (divergence-free) parts of the colour map, each derived from a potential field — a scalar one χ(c) for the former, and a vector one η(c) for the latter. due to simple connectedness of g, no harmonic component is present in the above: the constant ‘lift’ term l represents an overall colour bias (either neglected or incorporated into t) for chromatically-additive colour models like srgb, as well as cie xyz and dci x'y'z'. the gradient of the gamut mapping can also be considered, which is a more complete (and complex) mathematical object, called a (n,m)tensor field, [4], depending on both the source m channels and the target n channels. t is the generalized tonal mapping, or transfer characteristics which, in rgb spaces, models overall colour correction (incl. lightness and saturation changes). h is the field describing local colour-component cross-talks and global hue shifts. notably, t field too may incorporate hue shifts, especially for those colours c, where the inter-channel ratios are not preserved, i.e. r(c) : g(c) : b(c) ≠ r : g : b. colour-correction languages often use the lumachroma colour model (e.g. the la*b*, y'uv, y'cbcr and y'cx'cz' spaces), or the cylindrical colour model (e.g. the hsl space). in the case of hsl for example, the author usually suggests joining hue h and saturation σ together into a complex parameter called chroma ς and defined as, [5]: (where arctan2 is the secondary arc-tangent, which is reminiscent of quadrant allocation ˆˆ ˆ( ) ( , , ) ( , , ) ( , , ) ( ) ( ) ( ) ( ) r r g b g r g b b r g b χ = + + = + = ∇ + ∇ × + l c r g b t c h c c c lη 1504/15 | cultura e scienza del colore color culture and science “run” the algorithm, than applying more complex mathematical formulæ. third, a clut can hardly be interpreted only by specific software able to read its encoding and is useful only on specific picture(s) it was intended for: quite a black-box ingredient for the motion-picture recipes. the latter aspect may have been advantageous in the past, but is now mostly a downside, when cinematographers, colourists and vfx artists really need to transfer colour corrections from the on-set pre-grading sessions throughout the whole post-production pipeline, up to the theatre room, and capable of doing so in the most advantageous and, above all, interoperable way (cfr. §5). moreover, lots of workflows with so different and “undisciplined” uses of cluts exist —be it either for technical and creative intents— such that no generalized use can be made of a clut as long it is tailored for a specific project. it is hard to invert (i.e. to “reverse-engineer”) the mathematical operations baked into a clut, especially for post/vfx labs which do not enforce a thorough colour management across their pipelines. that is even worsened when materials from different sources (camera makes, film emulsions, cgi rendering, …) come all together in place. discrete-calculus tools allow the extraction of quantities essential for the analysis or synthesis of a colour transformations: estimating colour differences, hue shifts in degrees, boundary wedges for evaluating out-of-gamut (oog) colours, etc.. when technical problems of higher level arise in colour correction (e.g. colour characterization of specific input or output devices, or proper gamut mappings between footage with different colorimetry), this usually translates into more sophisticated mathematical tools to be employed, often derived from differential geometry, harmonic analysis and multidimensional interpolations, [4]. for example, a more careful shaping of a tone-scale curve is usually necessary when modelling the transfer characteristic of a nondigital device, e.g. sensor noise or the soughtafter 35mm film print emulation (fpe, cfr. fig.2): three control points as provided by a cdl ([11]) or a 3-way color-corrector (cc) are no more enough and the three channel functions r(r), g(g) and b(b) need to stay non-decreasing (i.e. invertible). this helps better trim the effective contrast on all the tonal ranges. when the three functions are uneven with each other, a hue shift inevitably occurs, as the hue is not preserved by the same input triple (r,g,b) any more. imposing hue-invariance means adding constrains that need to be correctly formulated), i.e.: ˆˆ ˆ( ) ( ) b g r b g r g b b r r g    ∂ ∂ ∂ ∂ ∂ ∂  ∇ × = ∇ × = − + − + − =    ∂ ∂ ∂ ∂ ∂ ∂     l c h c r g b 0 for b* and a* and commonly found in all the programming languages). 3. colour look-up tables, aka colorlut, aka clut, aka simply 'lut' while the above formalism is useful for technical operations like colour space conversions and “overall” colour corrections not done on a sceneper-scene basis, more complex transformations may be needed, especially when creative intent is included, [8]–[10]. in this case a closedform formula for the transform might not exist; interpolation, though existing in principle, might not be computationally compatible with the creative need of real-time playback of highresolution (often uncompressed) image/video files (essential for evaluating and creating the so-called grades). for this reason the continuum formalism may be well abandoned at this stage, and replaced by a colorlut (colour look-up table, or clut, [6]) which is a discrete-mapping representation of it on a finite, m-dimensional grid of n points per input colour channel, with each point being a n-tuple in the output colour space (e.g. in the shape of a n×n×n rgb cube). it is an explicit mapping between a sample of input code-values into output code-values (which may or may not act between the same colour space), while the result on intermediate source colours is obtained by interpolation [3]: for this reason a clut can be also used to approximate continuum formulae as those for mapping a colour space into another (e.g. from a rgb one like rec.709, [10], to cie xyz, cfr. fig. 2c). a type of clut approximates the mapping channel by channel (therefore called 1d-lut, or colour curve in different contexts); another type acts as a full orthogonal sampling of input colours; the latter —because it usually maps between 3-channels colour spaces— is specifically called a 3d-lut whereas, mathematically, it is a discrete n-dimensional vector field l(s), where s∈g is the input colour codevalue of the source m-channel gamut g⊆irm (cfr. several samples in fig.1, where m=n=3). the reason why the clut implementation is so widely used is manifold: first of all, provided the appropriate density of n input value per channel is used (17×17×17 samples in fig. 2 is a common, but yet not enough coarse-grained choice), it can represent any non-linearities in the colour transform (accounting from the most complex primary colour corrections, up to a 35mm film’s dye cross-talk, as is the case for 3d-luts). secondly, it is implemented via simple (and usually linear) interpolations on the other non-sampled colours, fairly scaling with the clut size n, and has therefore a smaller footprint in terms of cpu power and memory size needed to 16 cultura e scienza del colore color culture and science | 04/15 figure 1 plots of the output gamut l(γ) of 3d luts l whose input is the 173-points rgb cube g: a. identity mapping; b. colour-space conversion between hdtv’s “rec.709” and cineon printing density (cpd) “logarithmic” rgb spaces; c. from “rec.709” (gamma γ=2.6) to digital cinema (dci) cie xyz colour space; d. from cie xyz to dci’s p3 rgb colour space (γ=2.2 – notice the clipping at the cubic gamut boundary of p3); e. from cineon printing density log. rgb to cie xyz colour space; f. scenespecific creative colour grading lmt including 35mm print-film emulation. figure 2 – two different views of output gamut l(γ) of a print-film emulation (pfe) clut l engineered by the author (technicolor laboratories, rome, 2009), showing the synthesis work done adding additional points to the gamut of a kodak vision film in order to expand its latitute prior to 35mm scanning. 1704/15 | cultura e scienza del colore color culture and science more often simpler definitions of hue and saturation are used though, like which allows to have simpler analytical properties like imposing hue-invariance, means in this case solving the algebraic equation hue l(c) = hue (c) ⇔ another important constrain that is sometimes necessary, is the existence-of-inverse condition. this is especially important to guarantee that, once a grade is ‘burned’ within the raster pixels, original colours can still be recovered without degradations. it’s worthwhile noting that current postproduction tools only ‘burn’ a colour grade as the last stage of the process (earlier the information on the grades is carried along the pipeline as metadata-only by the colour-correction software). this is formulated as in [2]: 21 sat( ) 2 gb rb rg= − − −c c 2 3( ) hue( ) arctan 2 g b r g b − = − − c 2 1 sat( ) 2 sat( ) 2 r g b g b r b r g − −   ∇ = − −   − −  c c sat( ) 3 8 hue( ) sat( ) sat( ) ∇ ∇ = = c c c c 2 2 g b g b r g b r g b − − = − − − − det 0 ( , , ) r r r r g b g g g r g b r g b b b b r g b ∂ ∂ ∂ ∂ ∂ ∂ ∂ ∂ ∂ ∂ = ≠ ∂ ∂ ∂ ∂ ∂ ∂ ∂ ∂ ∂ ∂ l 4. on-set colour grading and its colour language (cdl) since things are now shot digitally and stay digital throughout the pipeline, one of the moviechain blocks to recently take advantage of this is principal photography, where early colour correction/grading can be done effectively, onset, just minutes after each clip is shot, cfr. [11], fig.3. creative colour correction (grading) information can be transported, from clip to clip, as they are originally shot, as a series of simple non-linear transformations controlled by 10 parameters (3 parameters by each of the 3 rgb channels, plus 1), each representing one degree of freedom of the creative colourist: ‘slope’, ‘offset’, ‘power’ triples, plus a ‘saturation’ parameter. a set of such quantities, transported for a whole video asset, cut per cut, makes up the 2014 oscars®winning american society of cinematographers’ colour decision list (asc cdl) and is a well-known example of simple mathematical equations at the creative service of motion picture colourists [5], [11]. this can also be re-written by means of three functions s (slope), o (offset) and p (power) and let s, o, p be the respective controlling parameters with identity values 1, 0, 1 respectively: • slope s(c;s)=sc (cdl analogue for colourists’ lift, despite slope fixes black point at codevalue 0.0, whereas lift fixes whitepoint at codevalue 1.0); • offset o(c;o)=c+o (cdl analogue for colourists’ gain); • power p(c;p)=max(0,s)p, which is the cdl analogue of a gammacorrection. figure 3 – example of commercial colour grading software gui with the main 3-way colour-corrector wheels. ( )( ) ( )( ) ( )( ) gr b r r g g b b r r r g g g b b b ˆˆ ˆ( ) ( ) ( ) ( ) ˆ ˆ( ; ); ; ( ; ); ; ˆ( ; ); ; pp po s r o s g o s b p o s r s o p p o s g s o p p o s b s o p = + + + + + = + + l c r g b r g b 18 cultura e scienza del colore color culture and science | 04/15 this is a non-orthogonal decomposition in 1stand 2nd-degree polynomials (slope + offset), plus a nonlinear function (power), thus the inner products may not “behave” well. it can be shown however (and this is in fact well-known practice done by every non-mathematician colourists working on still or moving pictures), that a sufficiently low number of such operators, governed by a few parameters (like weighting coefficients in a linear combination for linear algebra) allow for quite good approximation, thus leading to orthogonal decompositions of colour operators. where all the 1-parameter vector fields lk are known a priori, whereas the coefficients and the parameters k themselves are the real descriptors of the “look”. 5. the academy color coding system (aces) the academy of motion picture arts and sciences (ampas)’s science and technology council has been gathering a group of variegate experts from all the top-level production, postproduction facilities and software houses in the industry to put forward a solution unifying such colour management issues: aces, [1], [12]. the reason behind aces is the need to particularly address the plethora of colorimetries set by manufacturers’ digital equipment (both image-creating and -reproducing) — even many more so in the digital era than film processes ever had in the past. a similar need has already surfaced in the digital cinema industry: that is why its dci x'y'z' colorimetry derives from the device-independent cie xyz colour space ([3], [10]). unfortunately, as neither colorimetric cameras nor monitors/projectors exist as of yet, this colour-space choice has lead to reverting to a one within the rgb model, which is more practical, as well as aces mostly pertains to tv figure 4 sketch of the aces paradigm: the original scene is either captured by a real camera or generated in cgi. whatever the source, the corresponding input transform converts the codevalues into the smpte2065 colour space (except for the “ideal” ricd, which already produces smpte2065 pictures). using the output transform the pictures can then be transferred to any output device, like monitors (with any technologies), projectors, tvs, etc. and moving pictures. every colour-correction operators in the involved pipelines (from camera controls, to colour-grading suites, to projectors’ and tvs’ balance controls) are, in fact, rgbbased. version 1.0 of aces, [12], whose project the author has been cooperating on with the ampas experts since 2012, is a framework with centralized colour-management paradigm, developed after many years of pre-testing among facilities and companies in the industry, where the image is evaluated according to its colorimetric digital representation. please refer to fig.4 for a schematic throughout this chapter. first of all, aces defines ap0 and ap1: two sets of rgb primaries for the four aces colour spaces. ap0, whose cie xy chromaticities are (0.73470,0.26530) for red, (0.,1.) for green and (0.0001,0.0770) for blue. ap1 primaries’ chromaticities are (0.713,0.293) for red, (0.165,0.830) for green and (0.0128,0.044) for blue. both use cie d60 illuminant (0.32168,0.33767) as white-point and physical blackpoint at cie xyz triple 03. within aces colour pipeline the image is considered as virtually captured by a reference input capture device (ricd), which is an idealized digital ‘camera’ recording in a rgb colour space called smpte2065 after the standard that defines it. another important aspect is that smpte2065 is a scene-referred colour space, i.e. the codevalues represent mean relative exposures to the one captured from a perfect reflecting diffuser — apart from a 15% glare. in ap0, this accounts for a normally-exposed 18% grey card acquired by a ricd mapped to the rgb triple (.18, .18, .18). any real camera imagery and colorimetry is brought into the pipeline by means of a colour gamut mapping called aces input transform, which basically converts all the camera’s colorimetry into smpte2065. currently, input transforms for most of the patented, cinemagrade cameras like the arri alexa, the cameras 1 ( ) ( ; ) c k k k θ = = ∑l c l c 1904/15 | cultura e scienza del colore color culture and science figure 5 real-world aces testing to compare arri alexa xt (shown here), red™ epic and sony f55 cameras on the same technical set and aces colour space (also courtesy of dit e. zarlenga). figure 6 main aces v1.0 components in place: footage shot in alexa camera’s native arriraw frame-per-file format (in log.c colour space) is technically processed by an input transform to become scenereferred smpte2065 colour space. this is where color grading is applied upon (in temporary acescc space). the cdl designed during principal photography (on-set) pre-grading is conceptually applied above this grade, but below optional creative-technical transforms like pfe. the file is then ready to be saved in aces-compliatn openexr sequence (smpte2065 colour space) or can be sent to a display device passing through an output transform. by red™, the fx5 family by sony, the cameras by blackmagic design, and the cinema-eos™ family by canon, are provided; each maps the sensor’s proprietary gamut (called arri log.c, red.log, s-log/s-gamut, bmd.log and canonlog respectively), parametrized by shooting settings like equivalent sensitivity (iso) or correlated colour temperature (cct), into scene-referred smpte2065 codevalues. the author has also been active in italy for promoting the use of aces with several initiatives, [1], including a real-world, on-set test to compare aces freamework originating from different, high profile cameras, up to a full vfx and digital cinema mastering pipeline: fig.5 is the result of the technical photography session. at the other end of the pipeline, smpte2065 colorimetry is converted to the gamut of the displaying device and chromatic adaption by means of an aces output transform: among the others there is one, for example, for digital cinema mastering (dci p3) in a dark surround, two for standard broadcast tv gamut (rec.709), and two for uhdtv (rec.2020) — each having one for a brightand one for a dark-surround adaption. from a colour appearance model (cam)’s perspective, the output transforms take care of the viewing environment as well: so several output transforms may exist for the same device, but under different chromatic adaptions. all the output transforms have a common first mathematical block, called the reference rendering transform (rrt). please refer to fig.5 for a block-diagram of aces version 1.0 main components. all in all, smpte2065 space uses ap0 primaries, has trivial transfer characteristics (i.e. it is photometrically linear, i.e. “gamma-1.0”) and represents the baseline for all the aces pipeline — and the widest gamut as well, which is also suited for long-term archiving, cfr. fig.6. codevalues are usually encoded as 16 bits/ channel floating-points (‘half-floats’ as per ieee 754-2008 standard), and archived in a specific frame-per-file variant of the openexr file format, cfr. [14]–[15]. it is within this space that images are mainly worked on, with exceptions when it is technically convenient or mandatory to use temporary, welldefined colour-spaces for specific purposes: • acescc has ap1-primaries, “logarithmic” transfer characteristic, 32 bits/channel float encoding optimized for film-style colour correction, [13]; • acescg has ap1-primaries, photometrically-linear, 16 or 32 bits/ channel integer code-values, optimized for cg and painting applications that scarcely support images represented by floating-point codevalues, [16]; • acesproxy has ap1-primaries, the same logarithmic characteristic as acescc, 10 or 12 bits/channel integer encoding, optimized for real-time transport of images over physical links (e.g. the sdi cables family) that only support integer code-values, yet logarithmic encoding is still needed for on-set color correction applications, [17]; similarly, output-device compatibility is provided by first mapping to another ideal 20 cultura e scienza del colore color culture and science | 04/15 output reference display device (rdd) via the aforementioned rrt, and, whence, by means of a discrete mathematical formula called output device transform (odt), which depends on the output colour space and, ultimately, on the output device’s transfer characteristics (e.g. monitors, projectors, printers, d-cinema devices, etc.). aces images are stored in frame-per-file ordered sequences, encoding each frame as a openexr file [14], together with aces-specific metadata optionally written as well in a “sidecar” xml file called aces clip-container. ideally, any sensitive colour operation (both for technical and creative intent) should take place in either the smpte2065 or the acescc colour spaces (which act like a pcs in the icc paradigm), where any operator acts unambiguously. creativeintent operations, in particular, are stored in the so-called look modification transform(s) (lmt), which are applied before the output transform. 6. conclusions: the colour 'look' of a film several professionals in the video, postproduction and di world, as well as colour scientists and vendors, have long tried to define what technically “look” means in this context. in the author’s opinion, science, experience and common practices can sum up together to the statement that currently a “look” is the ensemble of creative colour decisions made for a specific set of scenes (e.g. scenes shot to represent the same lighting and dramatic situation, if not even possessing location/temporal unity) that neither pertain the technical properties of the colours themselves nor the devices/media used to reproduce them. in this sense “look” is different from “film look”, as the latter also includes colour characteristics due to combination of a film’s emulsion, development and printing processes (which can of course be emulated). a look applied to two differently-exposed and -coloured scenes not to chromatically match them (that’s what the same-name phase of a colour correction session is about), but rather to give both the same visual impact, in the director’s and/or cinematographer’s minds, the incisive ‘colour fingerprint’ unique to that specific product and cinematography; the ‘look development’ phase has therefore been starting earlier and earlier in the production phase, up to taking place on-set, with the help of proper pre-grading workflow (e.g. the one proposed by technicolor di supervising colourist peter doyle for harry potter vii, dark shadows and paddington full-feature films). the lack of interoperable schemes, incompatible file formats and colour operations —even a unified terminology— has prevented many colour manipulations from currently happening, or at least made this much more difficult and prone to errors or lack of precision. this cannot be any more delayed since all film processes have turned completely digital, and this is where the author’s contributions have been focusing on in the latest years. unifying the post-production terminology and mathematical figure 7 chromaticity comparison between aces (smpte2065) gamut other well-known rgb colour spaces. 2104/15 | cultura e scienza del colore color culture and science formalism (which were traditionally tied up to different post-production laboratories’ own film processing technologies and manufacturers’ secret sauces) means creating a common baseline to start from and communicate with mainstream color science. aces is another step up in the attempt to create common processes and workflow to ease interoperability and help to future-proff archival footage. of course all of this is a process, therefore it is not meant to be set in stone but rather continually progress as new technologies, methodologies and, above all, creative eyes and minds turn up bringing along their expression techniques and visions — for this process to drive them all along together. bibliography [1] w. arrighetti, “the academy color encoding system (aces) in a video production and post-production colour pipeline”, colour and colorimetry, xi(b), maggioli, 2015. [2] w. arrighetti, “new trends in digital cinema: from onset colour grading to aces”, at chroma: workshop on colour image between motion picture and media, chroma. di.unimi.it, sept. 2013 [3] w. arrighetti, “colour management in motion picture and television industries”, colour and colorimetry, vii(b), 63–70, maggioli, 2011. [4] w. arrighetti, mathematical models and methods for electromagnetism in fractal geometries, ph.d dissertation, sapienza university of rome, rome, 2007. [5] w. arrighetti, “colour correction calculus (ccc): engineering the maths behind colour grading”, colour and colorimetry, ix(b), 13–19, maggioli, 2013. [6] w. arrighetti, “moving picture colour science: the maths behind colour luts, aces and film ‘looks’”, color and colorimetry, viii(b), 27–34, maggioli, 2012. [7] s. westland, c. ripamonti, computational colour science using matlab. wiley, 2012. [8] colorimetry, second edition, commission internationale de l’éclairage, publication 15.2, 1986. [9] m. petrou, c. petrou, image processing: the fundamentals, wiley, 2012. [10] c. poynton, digital video and hd: algorithms and interfaces, morgan-kaufman, 2012. [11] a.b. benitez, l. blondé, b. lee, j. stauder, h. gu., “asc cdl: a step towards look management”, proceedings of ibc 2007. [12] academy color encoding specification (aces), society of motion picture and television engineers (smpte), standard 2065-1, 2012. [13] acescc, a logarithmic encoding of aces data for use with color grading systems, specification s-2014-003, academy of motion picture arts and sciences (ampas), v1.0, dec. 2014. [14] openexr file layout, openexr working group, www. openexr.com, apr. 2007. [15] aces image container file layout, smpte, standard 2065-4, 2013. [16] acescg, a working space for cgi render and compositing, s-2014-004, ampas, v1.0, dec. 2014. [17] acesproxy, an integer log encoding of aces image data, s-2013-001, ampas, v2.0, dec. 2014. [18] f. pierotti, “the colour turn: l’impatto digitale sul colore cinematografico”, bianco e nero, lxxv(580), 26–34, carocci, rome, sept.–dec. 2014. 95 color culture and science journal vol. 13 (1) book review: yellow, the history of a color renata pompas michel pastoureau: giallo, storia di un colore, ponte alle grazie, 2019. pastoureau, m. (2019) yellow: the history of a color. translated by j. gladding. princeton: princeton university press. the publishing house “ponte alle grazie”, which for years has edited the italian translation of the books on color by michel pastoureau director in paris of the “école pratique des hautes études“ and holder of the chair “history of symbolism in the west” has published his fifth work on symbolism of colours: “yellow. history of a color” (€ 32). the book consists of the usual 240 pages in the cm. 23 x 23 format and stands out, as always, for the exceptional iconographic research. the text is divided into three large chronological chapters, subdivided in turn by subject, ranging from vocabulary to symbols, everyday life, social customs, scientific knowledge, technical applications, religious morals and artistic production. in the introduction, pastoureau warns that yellow suffers from a limited number of documents on which to conduct research, which is why the book also includes gold and orange. chapter a beneficial color (from the origins to the 5 th century) this chapter describes pigments, gold, dyes and the myths that described them. in the ochres of the palaeolithic, he describes the procedures for preparing ochres by cave painters 30,000 years ago. gold occupies two sub-chapters: in the blond metal he refers to the gold of the necropolises, bringing the prehistoric necropolis of varna and the sarcophagus of pharaoh tutankhamun as examples. in the mythologies of gold he recalls the golden age described by hesiod; the myth of the conquest of hercules' golden apples, that of jason's golden fleece, that of king midas who "represents the most ancient link between yellow, envy and avarice" and the legend of the rhine gold. in the sun cults, he points out that the sun has always been associated with gold and, in its place, with yellow. turning to dyes, pastoureau divides them into: dyeing yellow, in which he lists vegetable dyes, from saffron to reseda (which it is always translated as "guada") to safflower. wearing yellow in which he shows how until the late middle ages yellow in clothing was still appreciated. the case of clodius in which cicero's mockery of clodius is reported, describes him as a debauchee who wears yellow clothes, a purely feminine color. the following conclude the chapter: lexicon teachings analyses latin terms. the silence of the bible and of the fathers of the church where an abundance of gold does not correspond to a presence of yellow. chapter an equivocal color (6th-15th centuries) from this century on yellow turns towards negative judgements. the absence of yellow in christian worship is linked to the previous sub-chapter by examining the liturgical code of colours established by pope innocent iii. in yellow in the coat of arms pastoureau, who is an expert in this field, examines heraldry. 96 color culture and science journal vol. 13 (1) in an ambivalent symbology, he makes the transition from the coat of arms to the robes of knights. in the prestige of blond hair, he describes how much they were appreciated in medieval courts. in bile and urine he describes the medical practices of fluid analysis that charged yellow with filth and disease. envy, lies and betrayal develops the latter aspect, which by the end of the middle ages became the color of forgers , traitors and criminals. the robes of jan hus and judas shows how the yellow robe characterised traitors and became the symbol of jewishness. to the origins of the yellow star? develops the theme of yellow in the representation of judaism, while emphasising that there was no system of signs or colours common to the whole of christianity. chapter a little-loved color (16th-21st century) the chapter begins by noting how yellow is still a colour with a limited presence in europe today and suggests that its decline stems from its instability in painting and dyeing. painters' yellow is a section entirely dedicated to paintings and their reproduction. yellow of the scholars shows its diversified classification over the centuries. yellow in everyday life looks at the presence of yellow in painting, clothing and fabric samples. dictionaries and encyclopedias takes up the lexicological investigation of yellow from the first chapter, extending it to the 17th and 18th centuries in france. eastern trends attests to how the success of 'chinoiserie' in europe briefly contributed to the fashion for yellow. discretion, transgression, modernity attests to how in the 19th century yellow denoted a series of negativities: from prostitutes to asylums known as 'the yellow houses' and more. at the far reaches of yellow is orange introduces this shade pastoureau writes that it "began to distinguish itself from red at the end of the middle ages" and spread from the 14th century with the importation of new dyes: the "campeche wood" from central america (which in italy we call “campeggio wood") and the pernambuco wood from south america (which in italy we call "brazil wood"). it concludes with the strong presence in contemporary signage. yellow in our time concludes the book, with the criticality that, for different reasons, yellow suffers in our society, where it is recovered for its visibility, for example in taxis, in post boxes, in the waistcoats of the eponymous political movement. a book in which, alongside the historical seriousness of the text, the pleasure of the images predominates. 32 color culture and science journal vol. 12 (1) doi: 10.23738/ccsj.120104 emerging colours: new trends, demands and challenges in contemporary urban environments beichen yu1, simon bell1 1 esala, the university of edinburgh, edinburgh, united kingdom. aimeeyu24@gmail.com, s.bell@ed.ac.uk corresponding author: beichen yu (aimeeyu24@gmail.com) abstract the concept of colour in urban settings has traditionally been associated with architectural colour palettes or urban colour planning. however, in contrast to the generally whitish or grey architectural environment, the use of saturated colours presented in dramatic ways has emerged as a trend in urban settings since the beginning of the 21st century. this study examines this globally occurring ‘colourful’ phenomenon and argues that emerging colours have distinct features, varying from design intentions to design impacts. focusing on projects in urban public space, this paper positions the phenomenon in the contemporary urban context and attempts to explain the conditions and driving forces behind it. by exploring the use of saturated colours in a context, we argue that colour has been engaged as an active design element to respond to the demands and challenges of contemporary urban environments. furthermore, new demands can be observed that accelerate the spread of the use of emerging colours globally. we suggest that it is time for a critical review and evaluation of the phenomenon as part of understanding contemporary urban and landscape design culture. such an understanding will allow us to have updated references for environmental colour design in contemporary urban contexts, and to use colour effectively. keywords saturated colour, environmental colour design, contemporary urban environment received 14 october 2019; revised 27 november 2019; accepted 04 december 2019 emerging colours: new trends, demands and challenges in contemporary urban environments 33 color culture and science journal vol. 12 (1) doi: 10.23738/ccsj.120104 1. introduction colour has always been a controversial aspect within the history of architecture in western culture. with prejudices about colour and uncertainty when using colour in architectural design, the general image of built environments has been whitish or grey (although there are notable exceptions), especially since the advent of the modernist era in architecture (batchelor 2000:21–48). however, since the beginning of the 21st century, more colourful expressions have emerged in urban environments. unlike the conservative colour palettes in traditional environmental design, such as colours inherent in materials or prevalent neutral tones, the ‘new’ colours are vivid and bright and easily stand out from their surroundings. apart from the use of colour on architectural façades, these emerging colours have also spread to urban environments through forms of street art, temporary installations, and urban and landscape design. aware of the inspiring ways colour is being used, some studies have explored these ‘new’ colours in urban environments from different perspectives. for example, borsotti (2019) focuses on the use of strong colours in contemporary architecture with the intention of chromatic interventions and argues that colour serves different functions and should be considered as an integral part of architectural design. boeri (2017) considers colour in association with different components of the urban environment and proposes to understand colour from the perspective of placemaking (transforming spaces into living places), which can play a role in city transformation and urban colour planning. despite these differences in focus, researchers acknowledge the changing role of colour and emphasise the need to look into the function of ‘new’ colours in urban environments. to investigate how the ‘new’ colours interact with contemporary urban contexts from a design perspective, we focus on an assessment of design projects in urban public space, in which the outcome of the colour design is a collective decision and responds to specific demands. therefore, in this paper, the phrase ‘emerging colours’ mainly refers to the growing number of urban and landscape design projects in urban public space characterised by saturated colours that are distinct from and sharply contrast with their surroundings. through the comparison between examples of the new phenomenon and traditional environmental colour use, notable differences and tendencies of colour design in contemporary urban environments can be identified. 2. colour design as a new phenomenon in this paper we identify and present three main aspects to illustrate the features and trends of the emerging colours in urban public space. new phenomena and design decisions about the use of colour can be considered to be a result of constant interactions within contemporary urban settings. 2.1. the role and functions of colour architectural colour design and urban colour planning are the two major branches of traditional environmental colour design in urban contexts, which have been profoundly influenced by the historical perspectives on colour in architecture. in architectural discourses, colour has been deemed secondary to form (braham 2002) and a less important element of visual design which mainly serves decorative purposes (caivano 2006). for many architects, colour is an intractable element that should be carefully controlled, while ‘safe’ colour palettes are generally preferred (mclachlan et al. 2015). researchers and practitioners have both looked for the principles of integrating colour into the environment to create harmony, which in many cases, means that colour is an unobtrusive element in the design. nevertheless, in nature, a wide range of colours can coexist, and different colour combinations are considered as an intrinsic and regional feature, which gives character to landscapes (bell 2019). although the potential and function of colour in environments has been revealed in many studies (e.g., lenclos and lenclos 2004; swirnoff 2000; mahnke 1996), the role of colour generally remains ambiguous in many architectural practices compared to other design elements such as form, scale and shape. nevertheless, instead of being used submissively, the role of colour has been redefined in the emerging phenomenon in which colour has been used as an effective tool to achieve specific design intentions. since the 1960s fresh views and open attitudes towards bold and saturated colours have been introduced to the public through numerous art and design movements. the general acceptance and greater freedom of using colour have inspired more colourful expressions in urban environments. with the recognition of the potential and effects of colour, designers have begun to endow it with specific roles and functions in urban public space over the last few decades. learning from previous movements, such as supergraphics during the 1960s, saturated colours have been increasingly used in urban environments for different occasions due to their ability to attract attention, communicate visually and provide instant changes. the 1984 summer olympics in los angeles is a good example to show how vivid colours on a large scale interact with urban settings. as an instant and inexpensive emerging colours: new trends, demands and challenges in contemporary urban environments 34 color culture and science journal vol. 12 (1) doi: 10.23738/ccsj.120104 approach, colourful installations transformed the entire city into a venue for the celebration, while bright colours were also embedded in signage designs for wayfinding (jerde 2019). since the 2000s, more urban and landscape design projects started to involve saturated colours in ordinary situations, while the budget is no longer the determinant for selecting bright colours. examples can be found in many urban interventions such as superkilen park (2012) in copenhagen, pink street (2011) in lisbon, and garscube landscape link (2010) in glasgow, where vibrant colours were introduced to raise attention and claim the renewal of the places. the distinct colour features transformed monotonous sites from being a ‘nowhere’ into places with a new identity. bright colour palettes applied at large scale are believed to have positive psychological effects (mcmorrough 2007), which assist the process of urban intervention to generate a better ambience. in other design practices, colours have been selected not only for their attractive appearance but also for their capacity to build connections and associations, which allows colour to serve different intentions simultaneously. colour has always been applied as a powerful tool for visual communication and to increase publicity. like the famous case, coca-cola red, colour has been widely used to represent a brand or a product in advertisements. in the new phenomenon, these functions of colour have been introduced to the field of urban and landscape design to serve design intentions. a key example of this branding role of colour is the fourth edition of pigalle basketball court (2017) in paris, delivered right after the announcement of the new 2017 nike and pigalle fashion collection, which refers to the colour palette from the fashion collection (fig. 1). dramatic hues have been applied to this urban space in an attempt to define a new dynamic sports environment for the local community, while at the same time carrying out the function of promotion. the popularity of this colourful court on the web and in a real place increases the publicity for the fashion collection that shares similar hues. the colour palette creates connections between fashion products and urban public space and plays a definitive role in attracting attention and branding. the associations between colour and contemporary cultural icons make particular colours or colour combinations a powerful tool for communicating and publicizing ideas in urban environments. the art installation, pink balls, became a landmark during the annual celebration in the gay village of montreal (2011– 2016). over a hundred thousand pink balls suspended above the street created a stage for people to enjoy and celebrate their culture. inspired by the rainbow flag of the lgbtqi community, the colour pink has been upgraded to six hues from the rainbow spectrum in the latest version (cormier 2017–2019). the bright hues create an atmosphere of celebration while the symbolism of colour in this given context expresses the intention of supporting the diversity in society. the vibrant colours with embedded meanings not only appeal to groups who share the same culture but also general audiences who enjoy the colourful scene. fig. 1. pigalle basketball court, 2017 (left). photo © beichen yu. a selection of images from the search result of ‘pigalle nike 2017’ (right). emerging colours: new trends, demands and challenges in contemporary urban environments 35 color culture and science journal vol. 12 (1) doi: 10.23738/ccsj.120104 the above-mentioned examples show that the design of colour responds to contemporary urban settings directly, and saturated colours are selected intentionally to provide solutions for specific situations. instead of being an inconspicuous element in the built environment, the new colour scheme often creates a distinct contrast to the original colour palette in order to facilitate instant changes and new functions within the space. in this emerging phenomenon, the decision of colour is no longer limited by the framework for colour design in architecture and urban colour planning but is open to a broader range of options based on a better understanding of the role and function of colour in urban public space. 2.2. the participants of colour design in traditional environmental colour design, architects and professionals from relevant backgrounds are in charge of colour decisions, and in general, they tend to prefer neutral colours and ’safe’ colour palettes despite the significant changes in architectural styles (mclachlan et al. 2015). doherty (2011) argues that not many opinions on the use of colour are heard from urbanists and that artists appear to be more comfortable with colour than urbanists. it is unfair to assume that most architects are less familiar with chromatic expressions compared to designers or artists despite the fact that they receive more colour training during their education than architectural students (mclachlan 2013). however, it is notable that professionals from different disciplines may have different ideas and expertise in using colour. over the last two decades, creative groups from diverse backgrounds have begun to express their opinions about colour in urban environments. the increasing number of interdisciplinary collaborations in urban and landscape design and the popularity of public art encourage the appearance of new colour expressions. the saturated colour palettes that have usually been used in interior design, graphic design, fashion and art have been introduced to the urban realm, which blurs the boundary between urban environmental colour design and colour design of other disciplines. fig. 2. yellow is the core identity colour of southbank centre’s complex, 2019 (photo © beichen yu). designers from other creative backgrounds have brought their principles and strategies to colour design in urban environments. the entrances and staircases of the southbank centre in london were coloured bright yellow as part of the rebrand project of 2017 (fig. 2). also appearing on posters, billboards and a website, together with the typography, the bright yellow has been introduced as the core identity colour of the new brand (north 2017). the strategy of using distinct and coherent colour in visual identity design has been applied to public space, which makes it stand out as an integral part of branding. with the popularity of large-scale installations, artists have made the urban public space a stage to exhibit their use of colour. artists such as carlos cruz-diez, morag myerscough and felice varini mark the urban landscapes with their signature colour palettes. besides expanding the range of colour choices, designers and artists also introduce their frequently associated materials and skills into the urban environment to generate different colour effects. thus, media such as acrylic paint, pvc and fabrics allow the colours to be presented in various forms and locations rather than being restricted to architectural façades. since colour design can be carried out by different disciplines, corresponding reference systems should be built to evaluate the emerging colours in urban environments. 2.3. the target groups jean-philippe lenclos explored the associations between regional colour palettes and local identities with his concept of ‘the geography of colour’ (lenclos and lenclos 2004). colour has long been used as a way to express cultural identity and to maintain a sense of place within a community in vernacular architectural environments. lenclos’ studies imply that the communities that created colour expressions in their environments were often the potential audiences (the target group). since the 1960s, studies on environmental colour design have explored the relationship between architectural colours and elements including space, form, structure, light and function (e.g., mclachlan et al. 2015, nemcsics 1993), principles for urban colour planning (e.g., brino 2009; spillmann 2009) and environmental colour design in a contemporary context (e.g., lenclos 2009, porter and mikellides 2009). however, with respect to colour preferences in practice, traditional environmental colour design, especially in the urban context, usually considers the general public to be an audience rather than a codesigner. however, in many recent cases, colour design is tailored to the preferences and identity of specific groups. for example, when introducing trendy elements from popular culture among young people, sports courts around the emerging colours: new trends, demands and challenges in contemporary urban environments 36 color culture and science journal vol. 12 (1) doi: 10.23738/ccsj.120104 world, such as basketball courts and skate parks, have been cost-effectively renovated using dramatic colour schemes, which seem to be welcomed by young people. the colourful environments also accommodate and encourage other popular activities among the younger generations, such as taking selfies and making youtube videos. road crossings and pathways may engage eye-catching colours as a reminder for both motorists and pedestrians of road safety. bright colours are designed to raise attention when travelling through traffic and work as a signage for wayfinding. in contrast to the grey traffic roads, the applied vibrant colours help to claim the territory for pedestrians and cyclists in car-dominated cities (fig. 3). fig. 3. the pedestrian bridge luchtsingel in rotterdam, 2015 (photo © nanda sluijsmans/wikimedia commons). exaggerated colour expressions can also be used to attract tourists who are looking for photogenic scenes. the increasing flows of visitors can invigorate an area by bringing more opportunities to local business and improving public safety based on jane jacobs’ ‘eyes on street’ theory (1961). last but not least, these emerging colours in urban public spaces interact intensively with current internet culture. besides the actual users of the physical space, the aim of attracting the attention of potential online audiences is embedded in the colour design with the function of branding and promotion. eye-catching colours or colour palettes are selected in urban design to create an ‘instagrammable’ scene that helps to promote the spread of images on social media. bright colours create a strong and recognizable identity to a place in no time and new hashtags for people to communicate online. the fast spread of the colourful images on social media, in turn, attracts people to visit the place. moreover, the popularity of certain colours or colour combinations online also influences the decisions about colour in design projects. by responding to the online colour trends, pink, red and rainbow colours can be seen around the world in urban design projects despite their different geographical locations and other regional factors. 3. reasons behind the emerging colours in urban environments based on the discussions above, we suggest that there are four main reasons behind the increase of colourful places in urban environments in the 2000s. 3.1 preconditions for the emerging colours first, above all, the improvements in technology for colour application provides the conditions for more varied colour expressions in outdoor environments. the availability of pigments and coloured materials that are resistant to water and weathering, as well as to wear and tear by feet, enables the colour application to meet the design requirements. a wide range of materials available in different colour options gives designers the freedom to experiment with the performance of colour in a given urban space. second, the widespread love of saturated colours which has grown since the 1960s has been reinforced by the current internet culture during the 2000s. both general audiences and designers seem to have more positive attitudes towards having brighter and more vivid colours in urban environments. with the increasing participation of artists and designers from different backgrounds in environmental colour design, fresh perspectives of colour and new colour palettes have been introduced to urban public spaces. 3.2. demands of the emerging colours the two reasons mentioned above are the preconditions for this phenomenon, while one of the driving forces behind the emerging colours is that, when used strategically, colour can meet different demands in contemporary urban environments. public spaces always play a significant role in the social and economic life in the city. gehl and gemzøe (2001:10) further explain the traditional functions of urban public space and state that “public space has always served as a meeting place, marketplace and traffic space.” however, in contemporary urban contexts, public spaces are endowed with more sophisticated roles and are expected to respond instantly to different requirements. unlike the traditional public spaces which have specific functions and fixed property, many urban public spaces nowadays are required to accommodate various activities emerging colours: new trends, demands and challenges in contemporary urban environments 37 color culture and science journal vol. 12 (1) doi: 10.23738/ccsj.120104 such as pop up events, art exhibitions or commercial promotions at one or different times. as a design element, colour can transform a place in a short time and provide a new identity for the corresponding role of the urban public space. moreover, with the rapid growth of modern cities, more undefined or underutilised spaces are appearing in urban environments. in many modern cities, places such as roundabouts, underpasses, parking lots and utilitarian paths can often be undesirable or even unpleasant for urban residents. irrespective of the existing conditions, the application of vibrant colours can bring positive changes and a new image to urban voids by generating new attractions, activities and psychological comfort. besides being applied in urban intervention projects, saturated colours also emerge in contemporary urban environments because of their capacity to facilitate visual communication. many urban design projects use striking colours in branding, wayfinding and publicising ideas in public spaces where the exchange of information is becoming more frequent and more intense. last but not least, as discussed in the preceding section, another noteworthy reason behind the rapid growth of the phenomenon is the rising influence of internet culture since the 2000s. saturated colours in urban public spaces meet the enormous upsurge in demand for photogenic scenes on social media. due to instant broadcasting online, the popularity of colourful scenes inspires and encourages similar cases to be created worldwide. being aware of the positive influence and potential impact, more and more designers have begun to include colours which are popular in social media in their designs to reproduce that success in different locations. the preferences and demands of saturated colours in internet culture, in a way, promotes the widespread presence of saturated colours in contemporary urban public spaces. 4. concerns and discussions despite the positive changes brought about by increasing colour expression in our cities, there are a few concerns that we wish to address regarding this emerging phenomenon. with the development of pigments, the application of colour has been used as a fast and cheap method to provide immediate changes in current practices. a wide range of bright colours has been used on building façades in slums or declining regions such as santa marta in brazil (flecha et al. 2017) and panel buildings in tirana, albania (guaralda 2009) to provide quick improvements to existing environments. although the selection of colours and the way to present colour is more precise with the consideration of specific design intentions in urban and landscape design, there are other potential impacts on urban environments that can result from this upsurge in saturated colours. as mentioned above, with the influence of the internet, projects with distinct colour features are likely to attract more audiences and become known to people around the world. aware of the benefits of using saturated colours, especially colours trending online, similar colour expressions tend to be reproduced in different locations, regardless of the context. in some situations, colour design has become a trademark of the designer or the project while alienating it from the local context (e.g., the umbrella sky project 2012–2019). ‘successful’ colour palettes or approaches to colour design are produced as a tool kit that can be applied to anywhere in need of a new stimulus. homogenised colour expressions can mask the sophisticated details in the original environments and hide or suppress regional identity, which may reduce the connections between the place and local culture. another concern is the impact of the emerging phenomenon on the daily lives of local communities. with the specific intention of attracting tourists and broad online promotion, a place with attractive colour features can suddenly become a new landmark and a must-visit place for photo shooting. the over-popularity of the site may contribute to the potential issue of mass tourism that has been frequently discussed in recent years. amsterdam city council in the netherlands removed the famous ‘i amsterdam’ letters from outside the rijksmuseum in order to reduce the tourist overload and call for more attention to the place instead of using it merely as a selfie background (hitti 2018) (fig. 4). fig. 4. the ‘i amsterdam’ letters attract tourists who take pictures and selfies, 2016 (photo © tobias niepel/wikimedia commons). a massive influx of tourists is not only harmful to the authenticity of the place but also creates conflicts of interest between local communities and visitors. as a emerging colours: new trends, demands and challenges in contemporary urban environments 38 color culture and science journal vol. 12 (1) doi: 10.23738/ccsj.120104 successful icon of the media branding campaign, the pink street in lisbon is considered to be a strategy to promote a tourist-oriented nightlife spot and bring income to the city (nofre et al. 2018). however, the increasing popularity of the site among tourists and the lack of regulations have already caused negative social and spatial impacts on neighbours and their liveability, especially at night (nofre et al. 2018). therefore, we suggest that designers should consider the local context and have a better overview of sustainable development and potential negative impacts when introducing distinct and appealing colour features to urban public spaces. conversely, the application of colour can be used strategically to divert the flow of tourists to lesser-known places, and the negative influences on residential areas and overloaded attractions can be limited by controlling the timespan of the project. 5. conclusions by investigating colour design in contemporary urban environments, our study identified a design phenomenon characterised by the use of saturated colours in urban public spaces. since the beginning of the new millennium, more vibrant colour expressions are increasingly appearing in many cities around the world. compared to the traditional environmental colour design, colour has been used as an active design element to respond to new challenges and demands in urban public spaces. although we can catch a glimpse of the importance and the potential of the phenomenon by observing and summarising current examples, many crucial issues remain unclear. studies are required to help us better understand this phenomenon by exploring the relationship between the ‘emerging colours’ and traditional environmental colour design, its impact on social and economic lives, and the guidelines for the application of saturated colours in urban environments. hence, we suggest that systematic research on the phenomenon is necessary to clarify the functions and the impact of the ‘new’ colours, which will provide references for understanding and evaluating the phenomenon as part of contemporary urban and landscape design. 6. conflict of interest declaration the authors state that no actual or potential conflict of interest exists including financial, personal or other relationships with other people or organizations within the three years prior to beginning the submitted work that could inappropriately influence, or be perceived to influence, their work. 7. funding source declaration this research did not receive any specific grant from funding agencies in the public, commercial, or not-forprofit sector. 8. short biography of the authors beichen yu achieved her ma in urban design at the university of sheffield. she started her phd research at the university of edinburgh in 2015. her research focuses on colour design in 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(2000) the color of cities: an international perspective. new york: mcgraw-hill. color culture and science cultura e scienza del colore special issue on frcc2019 editors: verena m. schindler, yulia a. griber ccsj volume 12 number 1 2020 issn 2384-9568 color culture and science (ccsj) cultura e scienza del colore jcolore.gruppodelcolore.it issn 2384-9568 doi: 10.23738/ccsj.00 ance e227716 road: the directory of open access scholarly resources registrazione presso il tribunale di milano n. 233: 24/06/2014 volume 12, number 1, march 2020 doi 10.23738/ccsj.120100 publisher gruppo del colore – associazione italiana colore www.gruppodelcolore.org registered office: piazza carlo caneva, 4 20154 milan (it) peer review process all articles submitted to the color culture and science journal are peer-reviewed according to the following procedure: first review level the associate editors evaluate each article in order to determine if the topic and content are of interest to the journal. once the article passes the initial review, the associate editors select several referees from the editorial board based on their expertise in a particular subject area or topic. second review level each article is reviewed by two or three referees and submitted to a double-blind peer review process where both the authors and the reviewers are kept anonymous. referees are asked to evaluate the manuscript based on the following criteria: − originality − relevance to the journal’s aims and scope − technical merit and/or validity − soundness of methodology − completeness of the reported work − conclusions supported by the data − correct acknowledgment of the work of others through reference − effectiveness of the manuscript (organization and writing) − clarity of tables, graphs, and illustrations − importance to color researchers − relevance to color practices if the article is accepted with major revisions by the referees, the author(s) are asked to improve the article according to the suggestions of the referees. the revised article will then be submitted to a further review. after collecting the referees' reports, the associate editors make a recommendation on the acceptability of the article to the editor-in-chief. editor-in-chief maurizio rossi (politecnico di milano, it) deputy editor alessandro rizzi (università degli studi di milano, it) associate editors josé luis caivano (universidad de buenos aires, ar) vien cheung (university of leeds, gb) marco gaiani (alma mater studiorum università di bologna, it) robert hirschler (serviço nacional de aprendizagem industrial, br) agata kwiatkowska-lubańska (academy of fine arts, kraków, pl) marcello picollo (ifac-cnr, it) verena m. schindler (chair aic s.g. environmental colour design, ch) renzo shamey (nc state university, us) francesca valan (studio valan, it) editorial board members john barbur (city university london, gb) giovanni bartolozzi (ifac-cnr, it) laura bellia (università di napoli federico ii, it) berit bergström (ncs colour ab, se) giulio bertagna (b&b colordesign, it) janet best (natific, gb) aldo bottoli (b&b colordesign, it) josé luis caivano (universidad de buenos aires, ar) patrick callet (école centrale paris, fr) jean-luc capron (université catholique de louvain, be) daria casciani (politecnico di milano, it) vien cheung (university of leeds, gb) paula csillag (espm university, br) osvaldo da pos (università degli studi di padova, it) hélène declermont-gallernade (chanel parfum beauté, fr) reiner eschbach (xerox, us) alessandro farini (ino-cnr, it) christine fernandez-maloigne (university of poitiers, fr) renato figini (konica-minolta sensing europe, eu) raffaella fontana (ino-cnr, it) davide gadia (università degli studi di milano, it) marco gaiani (alma mater studiorum università di bologna, it) robert hirschler (serviço nacional de aprendizagem industrial, br) takahiko horiuchi (chiba university, jp) sandra krasovec (fashion institute of technology, us) agata kwiatkowska-lubańska (academy of fine arts, kraków, pl) francisco imai (canon, usa) lia luzzatto (color and colors, it) kevin mansfield (ucl, gb) veronica marchiafava (gdc-associazione italiana colore, it) gabriel marcu (apple, us) anna marotta (politecnico di torino, it) manuel melgosa (universidad de granada, es) anna grazia mignani (ifac-cnr, it) annie mollard-desfour (cnrs, fr) maria luisa musso (universidad de buenos aires, ar) galina paramei (liverpool hope university, gb) laurence pauliac (historienne de l’art et de l’architecture, paris, fr) silvia piardi (politecnico di milano, it) 3 color culture and science journal vol. 12 (1) issn 2384-9568 marcello picollo (ifac-cnr, it) renata pompas (afol milano-moda, it) boris pretzel (victoria & albert museum, gb) noël richard (university of poitiers, fr) katia ripamonti (cambridge research system, gb) alessandro rizzi (università degli studi di milano, it) maurizio rossi (politecnico di milano, it) jodi l. sandford (università di perugia, it) raimondo schettini (università degli studi di milano bicocca, it) verena m. schindler (chair aic s.g. environmental colour design, ch) gabriele simone (renesas electronics europe gmbh, de) andrea siniscalco (politecnico di milano, it) ferenc szabó (university of pannonia, hu) mari uusküla (tallinn university, ee) francesca valan (studio valan, it) ralf weber (dresden university, de) stephen westland (university of leeds, gb) alexander wilkie (charles university in prague, cz) additional editorial board members for this special issue kine angelo (norwegian university of science and technology, trondheim, no) doreen balabanoff (ocad university, toronto, ca) ingrid calvo ivanovic (universidad de chile, cl) verónica conte (university of lisbon, po) elisa cordero-jahr (austral university of chile, cl) annamaria di cara (design research associates, sydney, au) maria joão durão (university of lisbon, po) paul green-armytage (curtin university, perth, au) domicele jonauskaite (university of lausanne, ch) ivar jung (linnaeus university, se) robin kingsburgh (york university, toronto, ca) maggie maggio (aic study group on colour education, us) fiona mclachlan (university of edinburgh, gb) inez michiels (city of 8 design semantics, be) gabriela nirino larroquette (university of buenos aires, ar) zena o’connor (colour collective sydney, au) jada schumacher (fashion institute of technology, new york, us) justyna tarajko-kowalska (cracow university of technology, pl) jinghong wang (central academy of fine arts beijing, cn) country codes compliant with iso 3166-1 alpha-2 standard 4 color culture and science journal vol. 12 (1) issn 2384-9568 table of contents editorial 6 verena m. schindler, yulia a. griber three colour design proposals for the market square in warsaw 9 karolina białobłocka doi: 10.23738/ccsj.120101 color as a sign of urban transition in the city of bordeaux 18 aline barlet, audrey bousigues, alice herbert doi: 10.23738/ccsj.120102 colour design of textile architectural envelopes: an initial study 25 alessandro premier doi: 10.23738/ccsj.120103 emerging colours: new trends, demands and challenges in contemporary urban environments 32 beichen yu, simon bell doi: 10.23738/ccsj.120104 color analysis of birth space ambiances 40 ichraf aroua, faten hussein doi: 10.23738/ccsj.120105 an educational experience about color emotion and its design implications 48 cristina boeri doi: 10.23738/ccsj.120106 color lab ifrj: practical color exercises for fashion courses 57 milena quattrer, welton fernando zonatti, anna paula silva gouveia doi: 10.23738/ccsj.120107 5 color culture and science journal vol. 12 (1) issn 2384-9568 does chromatic lightness have an impact on the perceived odor of brazilian perfumes? 63 camila assis peres silva, clice de toledo sanjar mazzilli doi: 10.23738/ccsj.120108 ceramic products and their chromatic ‘dna’ markers 75 carla lobo doi: 10.23738/ccsj.120109 approaching ecological ambiguity through a non-divisionary understanding of colour in art 82 yulia kovanova doi: 10.23738/ccsj.120110 column book reviews: 89 jean-philippe lenclos: painter & designer (2017) colour strategies in architecture (2015) farbraum stadt: farbkultur in winterthur (2019) verena m. schindler 6 color culture and science journal vol. 12 (1) issn 2384-9568 editorial the first russian congress on color (frcc2019) was held at smolensk state university on 18–20 september 2019. smolensk is one of the oldest cities of european russia and is located on the dnieper river. the congress was organized by the smolensk state university, the research and education center ‘color lab’ of smolensk state university, and the study group on environmental colour design of the international colour association. famous russian scientists and colour experts from around the world presented their latest findings in such fields as, e.g., psychology, sociology, political science, literary studies, gender studies, philosophy, art history, product design, art, architecture, urban design, landscape architecture and colour vision. over the three days of the conference, participants delivered sixty-eight presentations in russian and english in three different forms: as oral presentations, skype talks, and posters. in total, more than 300 people from nineteen regions of the russian federation and twenty different countries participated in the congress. this special issue of colour culture and science gathers together a selection of extended papers presented at the first russian congress on color, which were published in volume 1 of the scientific notes of the color society of russia, smolensk state university press. all contributions of this special issue have been double-blind peer reviewed, revised, and rigorously edited to ensure a high quality standards. we warmly thank the twenty-two reviewers for their excellent work. the first four papers cover relevant topics related to colour in architecture and the urban environment: karolina białobłocka (poland) discloses precious archive documents she unearthed about colour design proposals for warsaw’s historic market square, which was restored after world war i, and later rebuilt after its complete destruction in world war ii. aline barlet, audrey bousigues and alice herbert (france) analyze the colours of distinct new buildings that mark transition zones in the urban fabric and contribute to the development and modernization of the french city of bordeaux. alessandro premier (new zealand) explores the colours of temporary and permanent textile architectural envelopes/façades of the 21st century including tensile structures, architectural installations, and buildings around the world. beichen yu and simon bell (united kingdom) identify a new trend in the design of public and semi-public space whereby saturated colours are used to meaningfully impact an urban place. the so-called ‘new phenomenon’ is analyzed in the context of the visual culture of the new digital society. the next two papers deal with colour in interior architecture: ichraf aroua and faten hussein (tunisia) inquire into the effects of colour in delivery and maternity spaces in france and tunisia via on-site colour analysis, surveys, and electrodermal activity tracking of women giving birth. their aim is to identify elements that are fundamental to creating an ambience in harmony with function, shape, texture, and the cultural context. 7 color culture and science journal vol. 12 (1) issn 2384-9568 cristina boeri (italy) employs colour emotion theory to develop an educational approach to colour design for interior space. the next four papers concern themes in different fields of research, such as fashion, perfume packaging, ceramics, and art: milena quattrer, welton fernando zonatti and anna paula silva gouveia (brazil) make use of subtractive colour theory in their practical colour exercises for fashion courses to deal with colour contrast and colour harmony. camila assis peres silva and clice de toledo sanjar mazzilli (brazil) show research results based on their experiments concerning the relationship between the perceived fragrance of perfumes and the chromatic lightness of primary packaging. carla lobo (portugal), explores the history of ceramic products, their migration over the centuries, and how foreign colours merge with local conditions to form a very distinct chromatic ‘dna marker’. yulia kovanova (united kingdom) discusses colour from an ecological perspective as developed through a gradualist and non-divisional approach and her own artworks. we wish you a very interesting, instructive, and joyful time reading! january, 2020 guest editors of this special issue on the frcc2019 verena m. schindler, art and architectural historian, zollikon (switzerland) yulia a. griber, smolensk state university, smolensk (russia) co-chairs of the study group on environmental colour design of the international colour association (aic) 8 color culture and science journal vol. 12 (1) issn 2384-9568 this page intentionally left blank 40 color culture and science journal vol. 12 (1) doi: 10.23738/ccsj.120105 color analysis of birth space ambiances ichraf aroua 1 *, faten hussein 1 * 1 research team on ambiances era, national school of architecture and urbanism enau, tunis, tunisia ichraf.aroua@gmail.com, faten.hussein@gmail.com * first authors corresponding author: ichraf aroua (ichraf.aroua@gmail.com) abstract color is an integral component of architecture. it is an expressive element which deals with lighting distribution and many other aspects. it has a preponderant role in defining and personalizing the character of space and its ambiances. in this study, we will focus on women in labor and how users perceive colors in such specific spaces through the sensitive experience carried out in birth institutions, how color can be integrated in the birth space, how it takes part of a special event, and how it modifies women perception. our research is at the crossroads of several disciplines. it focuses on analysis of stress levels for women in labor in different obstetric spaces, using electrodermal activity (eda) tracking that evaluates the arousal via skin conductance measurements. this quantitative study will be correlated to a qualitative one which is based on a descriptive approach that consists in the analysis of the role of color in birth ambiances by using photos of different birth spaces and information collected in different surveys. thus, the goal of this paper is to identify ways of choosing colors in the obstetric space and search for appropriate ambiances to improve a well-being experience of giving birth without stress and anxiety. keywords ambiances, birth space, color, birthing women, electrodermal activity received 15 october 2019; revised 28 november 2019; accepted 04 december 2019 color analysis of birth space ambiances 41 color culture and science journal vol. 12 (1) doi: 10.23738/ccsj.120105 1. introduction through cultures, color manifests itself as a deep inherent quality linked to the substances of objects and not as a superficial mark (tornay 1978). it is used to identify groups, to convey symbolic meanings and to experience an aesthetic pleasure. it is a component of the social and physical world around us. it doesn’t occur taken alone but it is associated to objects and events. its perception depends heavily on the context (social, spatial, temporal, ambiant, functional). color takes shape only when it begins to be perceived as a quality of a specific context. it is an expressive element in the design of life space which deals with lighting distribution. in primates, space perception is multisensory. ambiances solicit different senses, essentially through visual perception; color gives a sensual visual perception of space. it is one of different aspects of visual perception through which, in other primates, the exploration of any space begins. indeed, colors have an influence on the ambiance. an ambiance is born so of singular relationships between materials, lights, colors and individuals (caue de l’ain 2011:4). that is how it contributes to shaping the living environments. color is considered as a tool that influences the user’s perception and behavior (tofle et al. 2004, dalke et al. 2006, çiçek and gökçakan 2016). thus, color has an important role in the user’s space experience. color reveals certain meanings and symbolism in a close relation to psychological and physiological effects that it produces. each color is associated with a certain mood, a certain environment that affects the user's space perception and emotion. it plays a role in creating ambiance of pleasure, excitement, content and comfort for a user that supports the function of a space. popular culture suggests that color prompts different human responses: psychological, biological, and behavioral (o’connor 2011). color can be considered as a therapy. it can play a role in the healing process. some architectural and interior design books, such as kopacz (2003) and mahnke (1996), and technical reports such as those by hill (2008), provide information related to the role of color psychology and color therapy in architecture (o’connor 2011). color is a specific architectural variable that can be modeled to provide different space ambiances. nowadays, we notice the use of colors in healthcare environment. there is considerable agreement among architects, interior designers, and medical doctors that color may promote the well-being of the hospital users. indeed, color facilitates the spatial orientation and wayfinding of patients in the hospital (dalke et al. 2006). according to smets (1969), colors can affect the time experience of a hospital stay that is felt by patients. he compared the time spent under two different lights, red and blue. patients under the red light reported a shorter estimate of time spent than those who were under the blue light (ghamari and amor 2016). several studies have been conducted on the effects of color on the user‘s ambiance perception. küller et al. (2009) and al-ayash et al. (2015) demonstrated that a red room is more psychologically arousing than a blue room, which is perceived as pleasant, calming, and interesting. thus, color is important since it has the ability to heal and to comfort. yellow and red promote exchanges and excitement, while blue and green soothe and relax patients (sternberg 2009:40). in terms of ambiance, color creates ‘welcoming’, ‘homey’ and ‘pleasurable’ ambiances to ease the stress of patients by the use of warmer colors, to improve satisfaction and help patients sleep (dalke et al. 2006). birth space and birthing women represent a pertinent research case and we will explain in this paper how color design influences the sensitive experience of birthing women. 2. method this study is at the crossroads of several disciplines. in order to understand the deep relationship between color in birth space, the event of birth and women perception, we varied the methods. our research is composed of two parts: a qualitative study which will be correlated to a quantitative one. when choosing the fields of study, two different cultures are taken into consideration to explore a diversity of color space experiences, which are the french and the tunisian ones (fig. 1). fig. 1. hospital birth space in two different cultures: french (left) and tunisian (right). 2.1. qualitative approach color analysis of birth space ambiances 42 color culture and science journal vol. 12 (1) doi: 10.23738/ccsj.120105 the qualitative study is based on a descriptive approach. the descriptive method is adopted to analyze the colors used in three different french birth spaces situated in grenoble. we chose to analyze a delivery room and a maternity room of a hospital maternity, a clinic maternity and a birth center. the process of analysis begins with collecting photos and information in a survey. the process depends on the identification of the properties of colors used, its ambiance as well as its effects on women during the birth event. further, and by adopting a transposition of the results of the french qualitative study, we selected tunisian maternities that have the same architectural and ambiant characteristics as identified in the french ones. 2.2. quantitative approach we carried out our quantitative study that focuses on the analysis of stress levels (hussein et al. 2015, hussein et al. 2016) for women in labor in the maternity and neonatology center of tunis, using electrodermal activity (eda) tracking that evaluates the arousal via skin conductance. in this second part of our study, a multidisciplinary experimental protocol of two components is applied. it is organized as follows: a spatial characterization consists of analyzing colors used and capturing the emotional state of women in labor using electrodermal activity tracking. in addition, the sensitive experience of women in labor has been recorded through surveys. to realize this experimental protocol, a wearable biosensor device called e4 was used that measures emotional states (stress, excitement, happiness, and more). its data can be visualized by the software ‘e4 manager’ (fig. 2). our target population was five women in labor aged between 25 and 32 years. fig. 2. wearable biosensor device ‘e4’ (left) and its software ‘e4 manager’ (right). in this paper, we will present the results of one case that is representative of all those studied, and which shows how we can detect objectively the effect of an ambiance (light, color, odor, sound) on women in labor, and how an architect can model a conception of space taking into consideration those parameters. the e4 sensor was worn by each woman in the delivery room and the measurements stopped when she was transferred to a maternity room. the itinerary chosen to be analyzed was during the transfer from the delivery room to a maternity room. it takes about ten minutes. during this time, a record of the woman’s feelings toward the ambiance, and specially the colors, was done by taking notes and comments. 3. results and discussion in our field study, we focus on the sensitive experience of birthing women in birth space in two different spatial, social and cultural contexts. 3.1. french experience during our qualitative study in the french field, we visited, photographed and analyzed from the architectural and ambiant viewpoints three different types of space. we carried out surveys and did ethnographic observations to identify the relationship between space, color and the user’s perception. the french maternities were: maternity of the university hospital center, maternity of clinic belledonne, and the birth center ‘la maison’. beginning with the maternity of the university hospital center (fig. 3), the colors used in the delivery and labor rooms were white, a warm shade of yellow and a grey with low value of blackness. when asked, a woman who was giving birth there said, “yellow is a brilliant and happier color, the color of the sun, of joy; it makes the room shine.” while another woman explained her dissatisfaction with the grey color: “the spaces are good enough... apart from the delivery room. it is grey and austere. it depressed my husband too.” some research done by nikolic and nikolic (2012) and by tofle et al. (2004:58) proved that yellow evokes energy, dynamism and excitement, and its brilliance is most often associated with the sun. it stimulates the activity of women in labor. by contrast, another study highlighted that yellow should not be used in maternity units as it hinders the diagnosis for jaundice (dalke et al. 2006). in physiologic delivery rooms, a light blue-green color was added to previous colors. it is a great choice for creating a natural ambiance. the light blue-green color gives the impression of being in a garden. it has a calming effect. research shows that green, the color of plants and nature, represents growth and life (tofle et al. 2004). in the maternity rooms a light pink color was chosen for the walls with white and grey for the flooring. color analysis of birth space ambiances 43 color culture and science journal vol. 12 (1) doi: 10.23738/ccsj.120105 this combination creates a pleasant ambiance. it symbolizes nature and flowers, creating a calm and fresh ambiance. in the maternity of clinic belledonne, which is a private healthcare space (fig. 4), shades of a light pink color were used for the delivery room in order to offer to women in labor an ambiance of intimacy and warmth, in the opinion of midwives. pink is one of the warmer colors traditionally recommended for maternity units (dalke et al. 2004). one of the reactions of a birthing woman was: “the delivery room has very bright colors, it has different colors: a pink, a green and the blue turquoise; beautiful colors.” fig. 3. the use of colors in the maternity of the university hospital center, grenoble: a. labor room, b. delivery room, c1. and c2. physiological delivery rooms, d1. and d2. maternity rooms. photo: ichraf aroua, 2017. in the physiologic delivery room, a dominance of grey is observed with a touch of green. indeed, studies of nikolic and nikolic (2012) showed that the green has a positive effect on the reduction of anxiety and pain. on the contrary, greenish colors were not prescribed in a lactation room because they were linked to an operating theater (lópez-tarruella et al. 2018). grey is a neutral color; it is used to create a neutral ambiance, to highlight the green color. in order to create a more upbeat ambiance (dalke et al. 2004:17), it is not recommended to use it as a single color in a hospital space. for the maternity rooms, orange was used. this color is particularly popular and recommended for maternity units. it symbolizes energy and power; it evokes warmth, comfort, and reassurance (tofle et al. 2004:50, dalke et al. 2004:20). a recent study about the influence of environmental color in lactation rooms showed that warm colors, especially yellow and orange, tend to score highly for cosiness. as well, they are considered to be the homiest colors (lópez-tarruella et al. 2018). in spite of the positive effects of orange color in a birth space showed by some studies, its perception is still subjective. for example, a woman giving birth there was not satisfied with the use of orange. she said, ”the orange paint on the wall... it’s really very concrete; it is not something that is warm and welcoming… it is orange… like it explodes in my face.” this showed that the color effects on a woman are something personal, related to one’s taste and background. fig. 4. the use of colors in the maternity of clinic belledonne, grenoble: a. delivery room, b. maternity color analysis of birth space ambiances 44 color culture and science journal vol. 12 (1) doi: 10.23738/ccsj.120105 room, c1. and c2. physiological delivery rooms. photo: ichraf aroua, 2017. in the two previous maternities, the medical ambiance was really present. white dominated the walls and furniture. it had a clinical appearance; neutral and without vitality. other colors were used partially. while among patients, ‘whiteness’ connoted cleanliness and hygiene (dalke et al. 2004:19). fig. 5. the use of colors in the birth center ‘la maison’, grenoble: a1. and a2. delivery rooms, b1. and b2. living rooms. photo: ichraf aroua, 2017. the birth center ‘la maison’ (fig. 5) is considered as the recent form of birth space, which is seen as an alternative to giving birth at home. in this space, childbirth is considered as a natural process. it is characterized by a familiar and warm ambiance by using residential furniture. adding to that, the use of green, blue, pink and orange creates a welcoming and homey ambiance. the choice of color responds to these needs. the wall covered with wallpaper has a variety of shades ranging from white to grey. while interviewing the architect isabelle chameroy of the birth center, she justified her color choice by the fact that this variety of colors gives a woman in labor a sense of security and tranquility. a study confirms that it is recommended to ensure a distinct variety of colors to provide enough visual interest (dalke et al. 2004:19). an interviewed woman was satisfied with the chromatic ambiance: “i found the maximum of privacy in this room; it is warm and colorful.” 3.2. tunisian experience since a safe and satisfying birth experience depends strongly on the level of stress experienced by the birthing woman, we had to verify objectively the impact of color parameter in modeling birth space ambiances, and thus affecting the perception of birthing women. observations collected from our qualitative study on the french fields had to be completed by a quantitative study based on stress level evaluation. detecting situations of stress due to an obsolete control of colors and light in birth environments is the ultimate goal of this correlation between qualitative and quantitative parts of our research. to identify stress situations due to color and light parameters in birth spaces, we selected a tunisian field of study where architectural design represents most of the recommendations picked up in french maternities: maternity and neonatology center of tunis. it deals with medical aspects needed in labor/obstetric spaces and friendly and warm ambiances needed in maternity rooms. figure 6 shows the time-space interval chosen to be studied in this part, which is the time of transfer of a woman from the maternity room to the labor room, because of the variety of color and light ambiances. the delivery room is painted white. in the hall of the delivery block a linear touch of pink is added to the white walls. in the corridor, most of the walls are covered with traditional blue faience. finally, in the maternity room, only white is present. a 25-year-old birthing woman who had a vaginal delivery without epidural is chosen as a case study to detect stress situations due to specific color and light ambiances. figure 7 represents the curve of her electrodermal activity (eda). in this eda curve, we identify different stress peaks due to an increased stress level in the delivery room; some are related to the colors used, others to many physical parameters (mainly some sounds of clinical staff and monitoring machines). at the same moment of those stress peaks, the birthing woman complained about the white color. it was confirmed by the comments of the birthing woman. when interviewing her about the space ambiance, she showed her dissatisfaction with the white color frequently used in delivery rooms: ”white color color analysis of birth space ambiances 45 color culture and science journal vol. 12 (1) doi: 10.23738/ccsj.120105 makes me feel cold and its neutral aspect is not cheerful; it is unpleasant.” the white color and bright light characterizing the hospital birth environment increased anxiety and fear for birthing women. fig. 6. the use of colors in the maternity and neonatology center, tunis: a. delivery room, b. hall, c. corridor, d. maternity room. photo: ichraf aroua, 2018. fig. 7. electrodermal activity (eda) curve of a birthing woman. we note on the eda tracking that stress peaks persisted in the hall of the delivery block despite the use of a pink touch. it might be as a consequence of the use of white color and bright light. this was confirmed by the comment of the woman: “despite the presence of the pink, it feels white and pale. i cannot forget that i am in a hospital.” in the corridor, a slight decrease of the intensity of the eda is observed; then it stays constant until the entrance of the woman in the maternity room. in the corridor, there exists a combination of white and blue colors but the light is less bright and less intense. the wall cladding is a typical design used in many tunisian homes, so color did not play a major role here in decreasing anxiety of a birthing woman. architectural materials evoking home design also played a role. these results are confirmed by the woman’s comment: ”for me, the corridor is more pleasant by the faience colored blue which makes me feel at home.” in the maternity room, we detected on the eda tracking a peak of stress and it might be a consequence of artificial light. at this moment, the birthing woman asked to turn off the light and to open the window. many scientific studies showed that artificial light stimulates the cortex, provoking the release of adrenalin and inhibiting the physiology of birth (silva and shimo 2017, jenkinson et al. 2014). being able to adjust the lighting also provides the opportunity to change the mood. more than half (56%) of women placed high importance on being able to control the brightness of the light in their birth room (newburn and singh 2003:6). thus, brighter light can encourage activity and lower lighting can create a greater sense of privacy. color and light are an intrinsic characteristic of the visual sensations since they shape the relation between birthing women and their surrounding environment. they are a powerful factor in the recognition of objects and their delivery experience. 4. conclusion color analysis of birth space ambiances 46 color culture and science journal vol. 12 (1) doi: 10.23738/ccsj.120105 in this paper, we highlight a pertinent and original approach of detecting stress situations in birth space experienced by birthing women. there is the need for specific architectural design recommendations. in the light of the interest given to the question of birthing women and the birth experience in maternities, this study is pertinent as it shows the importance of careful coloring and lighting design in making the birth environment less or more clinical, affecting strongly the sensitive experience of such specific space users. the analysis of the comments of women highlights that the perception of colors in space is more subjective than objective. it depends on the woman’s personal experience, her background and her culture. in the case of the tunisian maternity, women disapproved the use of white. for them it was cold and unpleasant, while a french woman perceived it as a symbol of hygienic and aseptic ambiance. we also observed that the use of monochromatic color schemes represents a bad choice for birth space because the positive effects of color are closely associated with there being several colors in the same space. according to the results of the measurement of stress levels, we observed that every color creates a particular ambiance in a birth environment. it has a significant role in shaping the mood of women: stimulating or calming. the complexity of the hospital space showed that the stress situations can be caused not only by colors but also by other components such as sounds and smells, which may contribute to creating an uncomfortable ambiance. the affective dimension of this study represents a new response that shows potential on the perceptual dimension of a given category of birth space users. the aptitude to personalize a given color design while considering age, culture, physical and mental capacities of birthing women is an important step forward. such an objective would be aligned with a global well-being. 5. conflict of interest declaration the authors declare no potential conflicts of interest with respect to the research, authorship, and/or publication of this article. 6. funding source declaration: financial support was provided by the tunisian ministry of higher education and scientific research. 7. acknowledgment we are particularly grateful to professor jean-pierre péneau for framing this study, and to signals and systems team (u2s) from the national school of engineering of tunis (enit) for providing the e4 device and helping to analyze eda data. 8. short biography of the authors ichraf aroua ph.d student in architecture. faten hussein doctor in architecture. both authors are affiliated with the research team on ambiances (era) from the national school of architecture (enau), tunisia. their interests are focused on the altered perception in the urban and architectural space and the complexity of ambiances. references al-ayash, a., kane, r., smith, d. and green-armytage, p. 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(1978) ‘de la perception des couleurs à l’aperception symbolique du monde’. communications, 29, image(s) et culture(s) pp.119–140. https://doi.org/10.3406/comm.1978.1437. https://dx.doi.org/10.1590/1982-0194201700034 cultura e scienza del colore color culture and science 3104/15 | cultura e scienza del colore color culture and science 1 paola valentini paola.valentini@unifi.it 1 agas department of history, archaeology, geography, art and performance arts, university of florence, italy society in colour: italian television and the switch to colour while italy was proudly celebrating the advent of its own television system on 3 january 1954 and the first official broadcasts were starting to go out, at around the same time, the united states saw the arrival of colour television. indeed, in december 1953, the federal communications commission (fcc) approved the standard for colour television set out by the national television system committee (the same one that established the 525 line standard in 1941). the ntsc colour television standard was chosen for its versatility over other similar experiments, including its cbs rival, since its broadcasts were perfectly compatible with the black-and-white receivers which were widespread at the time. while italy stood out for black and white, in midjanuary 1954, colour television was authorised to operate commercially in the united states, and the analogue colour standard made its entrance on screen. it was then quick to be adopted in canada, south korea, japan and many other countries, and would remain in place up until the arrival of the atsc digital system in 2009. italy, however, officially seemed to have to wait until 1977. 1. politics and the colour experience italy in 1965, a rai studio in rome was set up with three colour television rca tk40 cameras and a colour tk40 telecine [1-2]. this was the start of the first “technical broadcasting tests”, while elsewhere in europe, britain, france and germany – albeit with an eight-year delay compared to the united states – introduced colour television broadcasting in 1967. in italy, however, the process came to an abrupt halt, and only seemed to fully open up again on 1 february 1977 with the official launch of colour broadcasting. the study of colour television, which is entirely overlooked in italy, is often merely limited to accounts of the (political) causes of this delay, which fail to deal with its full complexity. in italy, this “continuous succession and interweaving of speeding up and slowing down, of cuttingedge experiments and prolonged periods stagnation” is not uncommon and, according to peppino ortoleva, appears somewhat to be a peculiarity of italian history of telecommunications. indeed, at the very time when television may have seemed to be behind, in 1970, italy held the record – together with germany – for the first direct distance dialing [3]. the switch to colour television in italy conceals something more complex, which cannot be put down merely to technological developments. it is a complex story which is very much still to be written, the main aspects of which will be outlined below. often the delay in italy is associated with the battle over the standards running through the world history of colour. it began in the united states, where the choice of system, despite becoming the matrix for its successors, was by no means a painless process. yet, the contest was especially fierce in europe, where there was clash between two systems, pal (phase alternation line) and secam (séquentiel couleur à mémoire), between two powers (germany and france), between two political and expansionist concepts, and indeed between two opposing worldviews [4]. nonetheless, the impression in italy was that the late arrival of colour was only the result of uncertainty over the standard. accordingly, the final move to opt for pal, approved by the ministry on 5 april 1975, did not create any particular controversy or backlash in newspapers, where the news was reported in a cut and dry way. this is despite the fact – which has never been properly brought to light – that this decision not only threw out the french standard, but the entire italian isa system (suppression alternation identification) patented in 1972 by the turin-based company indesit. indeed, what had been occurring in italy took the form of a confusing but lively political debate, more than an economic-industrial matter. any attempt to untangle it is extremely difficult, as it often used as an opportunity to renew (and decide how to renew) the expiring television monopoly, a battle more of principle than substance, more of ideals than politics or economics. the picture is as hazy as the approach and stance adopted by the television phenomenon itself, between “empty and inane anti-capitalist leftism” and “overindulgence in crass consumerism”, as stated in 1977 by ugo la malfa, one the fiercest opponents of colour [5]. what is remarkable when reviewing the newspapers’ coverage of colour is the disconnect between the theoretical discussion on television and the path it has taken. in 1972, in the wake of the widespread eurovision colour broadcasts on other foreign channels, rai decided, on an experimental basis, to broadcast the munich olympics in colour, alternating – somewhat paradoxically – the secam and 32 cultura e scienza del colore color culture and science | 04/15 pal standards. as soon as news was given of this initiative by the italian government in early august, all newspapers – including those which were left-wing and traditionally almost indifferent to what they considered to be a mere and useless appliance – devoted a great deal of space to the story and to the debate around colour television. the minute-by-minute report of the ups and downs in the political reception of this decision by the ministry of posts and telecommunications follows a script that would be repeated for five years. “waste”, “unnecessary expense” and “distortion” in the face of italy’s crisis and real needs, were the most frequently used arguments, together with – something that was perhaps the most accurate premonition given what would take place at the end of the decade – an attempt to make people fear colour television as a “dangerous tonic”, a glare and mirage of an economic miracle that was now impossible [6]. more than the boycott of vehicle manufacturers, or than the italian communist party’s invectives against the persistent misinformation of television now in colour, what emerges from the news reports of the time is the depiction of an italian society where colour was already a reality for much of the country: “consumers in the north [...] already have colour tv sets: those in the lombardy and piedmont area are served by swiss tv from lugano, those around liguria and tuscany receive french tv programmes [telemontecarlo], and those in adriatic areas capture yugoslav broadcasts [tele koper]” [7]. within a year, the actual framework becomes clearer: the extraordinary measures put in place on 22 november 1973 to address the oil crisis directly associated television with the politics of austerity, and the “dangerous tonic” was defeated, putting an end to italy’s experiments in colour. policy imposed black and white (as well as a compulsory silence as the small screen was required to be turned off early); darkness fell upon italian cities, where shop windows and signs were turned off and public lighting was halved. there was already, however, a growing relationship between colour and the viewer. indeed, whether directly or indirectly, colour made a significant contribution to stabilising the television picture in italy. how the television picture was experienced by viewers in its first twenty years is extremely interesting. at least in italy, the economic expenditure of mobile external units set up for live broadcasting and the poor performance of radio links used to transmit the signal to the production centre, meant that, from the outset, television filming was carried out with film stock and arriflex cameras, which were much more manageable than the bulky “backpacks” for the magnetic recorder of portable cameras, and were often preferred by operators with a background in film. therefore, the base photographic image, albeit converted electronically, remained for a long time – at least until the mass spread of u-matic technology introduced by sony in 1971 but becoming massively widespread in rai in the second half of the 1970s. this technology became the workhorse of the first private networks – the standard for filming not only documentaries and news reports, but services including the much-loved sports coverage, starting, for example, with the football match summary. moreover, when tv serials opened up to the outdoors (being initially made entirely live in the studio using small models and effects), they opted for the more flexible film cameras, mixing cinema film and other entirely electronic footage with telecine. it is not easy to establish, in this era of craftsmanship, whether what was in play was a consolidated practice or a particular aesthetic choice of the producers and directors. for instance, already in l’isola del tesoro (1959), anton giulio majano uses film to show, in just a few minutes, a pirate falling from a brig (entirely rebuilt in studio) in the real waters of lake fogliano. conversely, in il mulino del po (1963), sandro bolchi shoots in film the famous film credits superimposed over the flowing river, while to achieve the famous flood, she chooses to flood studio 3 in milan. what is certain, however, is that the eye of the viewer perceives, with some degree of clarity, the difference in texture between the two images, which opposes the above-mentioned scenes, as well as the medium close-ups of newscasts with recorded services and an entirely different lighting distance [8]. colour increases this ontological genetic instability of the television picture, which the general “overflow”, so to speak, is not fully able to conceal; in actual fact, it is fuelled by the external environment. first, the viewer’s experience starts to bring about an interaction between the blackand-white television pictures and their colour print counterparts. the advent of television runs parallel to the revival of the rotogravure, characterised by photojournalism and colour pages, such as in epoca; in magazines with a greater focus on the television world, colour still seemed to interact directly, supplementing or perhaps attempting to overtake the small screen. for instance, in 1962, “bolero film” accompanies a service on canzonissima with an array of colour shots, half a page large, on the ballet and costumes worn by mina in the episode aired that week [9]; at the same time, the weekly publication successo, presented an unusual interview between the famous singer and luchino visconti, accompanying the text not only with black-and-white feature of the restaurant encounter between the two, but also with several shots of mina on the set, as lina cavalieri, during the making of a carosello for industria italiana della birra (figures 1-2) [10]. the relationship between the text in black and white and the paratext in colour also relates to cinema, where it was not uncommon for black 3304/15 | cultura e scienza del colore color culture and science and-white film to clash with the colour of flyers or posters (such as l’avventura, michelangelo antonioni, 1960, or rocco e i suoi fratelli, luchino visconti, 1960). nevertheless, film paratexts now have a narrative or symbolic relationship with the film subject, representing a form of novelisation. for this very reason, the preferred choice was for illustration, such as in the famous posters of carlo campeggi or angelo cesselon, and where the film frame is used, the image opts for pseudo-toning change or strong colour backgrounds charged with symbolism. whereas, in the case of colour television paratexts, the relationship seems to be of a calligraphic and didactic nature with both a “faithful” use of colour and, at the same time, the powerful performance of four-colour coated paper, which becomes an emblem of the post-war “universe of coloured objects” [11]. as such, the colour image seems to be a complementary experience to black-and-white television. the above example of mina is not accidental: the significance of clothing and fashion, make-up and disguise is an essential part of constructing this character, and the periodical’s images not only make the viewer dream of lavish dressing tables, but help to complete the feel of the scene. nonetheless, through its relationship with paratexts, colour also shows a television picture which is far removed from that commonlyprojected window on the world: a manufactured and unstable image, which at the time in italy, was incomplete and, therefore, awaiting integration 2. colouring reality: sport and games shows in 1978, on the pages of corriere della sera, luca goldoni remarked: “today, italy’s television unity is a past memory, we have now returned to the municipalities and signorias. every district has its own private antenna; people no longer converse on the train, but rather just brag about who gets the most channels. if two travellers realise that they have both seen the same programme the night before, they embrace one another” [12]. the commercial sale of colour tv sets led to the spread of the remote control, which came included with all of them, and the transition to colour coincided with the widest proliferation of private and commercial broadcasters and with the practice of “zapping” [13]. however, as mentioned above, for some time, viewers did not all have the same perception of the television picture, so much so that, in italy, it somewhat questioned – or made into a reconstruction – that sense of immediacy and of living nature that would would immediately characterise it. the perspective on colour shows a complex and protean television picture, which was far from that mere framework or window onto the world, that would only be fuelled by the meaning constructed by the live coverage from the late 1970s. the relationship and interference between the television picture in black and white and paratexts in colour soon came together with an audiovisual text identity, where the colour system varied according to its communication channel. the crisis and need to renew rai’s production, leading to a close dialogue with cinema [14], which once again would be over-simplistic to dismiss as a generic “transition to film”. in actual fact, it was a very complex situation both in its causes and its consequences: from the inability to dub with magnetic tape, thereby excluding this option for large international co-productions (l’odissea, franco rossi, 1968), through to the choice between 35 mm (la strategia del ragno, bernardo bertolucci, 1970 or i clowns, federico fellini, 1970) or “inflated” 16 mm (l’orlando furioso, luca ronconi, 1975). the question of colour – whose mere adoption was the result of various and complex causes – has also been addressed with an equally simplistic approach and cannot be reduced to how close the writer was to the world of television. whilst the choice of black and white in francesco d’assisi (1967) by liliana cavani may be traced back to her previous television reports, this is not the case of leandro castellani who, despite also being an exponent of television reporting, is motivated – as he himself acknowledged – by the latest developments of the american cinéma vérité and its different use of black and white for his le cinque giornate di milano (1971). at this stage, colour had a fundamental importance which one must begin to reconsider. firstly, the television picture continued to find its colour elsewhere. often our memory fails us and we tend to forget that the greatest successes, such as le avventure di pinocchio by luigi comencini (1972), and the most daring experiments, like the aforementioned furioso by ronconi, were seen at the time in black and white. yet, we also tend to forget that our colour perception of these works is not so much due to the fact that they figure 1 (left) – photograph of the set of carosello by industria italiana della birra (in successo, march 1962, p. 63). figure 2 (right) – part of the television frame of carosello by industria italiana della birra 34 cultura e scienza del colore color culture and science | 04/15 were aried in colour in following decade, but because of the concurrent availability of colour in cinema theatres: la strategia del ragno was aired on sunday 25 october 1970 but gained its censorship certificate on 6 october the following year, embarking on an autonomous life of film; at a shorter distance apart, comencini’s pinocchio, aired in april 1972, hit the screens of major cities in august. in this period of revival of television narratives, things become more complicated when widening our scope to the above-mentioned foreign broadcasters in the italian language. we might narrow it down to one case in point: from the 3 october 1971, the rai viewer was able to see ufo in black and white, a great international success from the british channel itv, whose episodes were aired in colour in italian-speaking switzerland the year before under the title minaccia dello spazio, which could be received in a large part of italy. that’s not all: given its success, the producer of the the television series, kent, made feature films by assembling scenes from “swiss” tv series in colour, making it finally possible to show everyone in colour the fuchsia-haired female protagonists or the futuristic base of the shado. it was not by chance that the first of these films, allarme rosso… attacco alla terra! (1973), was touted as “a great colour film that you’ll never see on tv”. last but not least, one can see how colour became a central element through a correct and thorough understanding of these particular hybrids, these products of “cinema-television” where the co-occurrence of film and television material – seen in early tv soaps – becomes an integral part of the text and subject matter and, once again, survives the apparent homogenisation caused by telecine. indeed, the factors at play are not only the clash between cinema and television with different areas of competence in terms of viewing, or the role of the frame and its relationship between the big and small screen, but also the duality of light and colour between cinema and television. the latter is the result of the particular interplay in television between chrominance and luminance signals (used for the brightness of the image which is, in fact, the black-and-white signal) [15]. this aspect is well-known to the great cinematographers, who often work on these productions, such as vittorio storaro, pushing the boundaries of film photography or breaking that of television, devoid of strong tonal contrasts. colour television was yet to triumph in the wake of audiovisual narratives and rai’s increasingly sought-after twinning with cinema, which – as caustically observed in 1977 by lietta tornabuoni – was turning rai into “an institute of historical and nostalgic studies”, but saw victory with a completely unexpected area of the state monopoly: sports. the regular broadcasts of the yugoslav network tele capodistria in full colour (since 6 may 1971) not only attracted viewers with cartoons or tv series, but also through the european coverage of major sports events. the viewer alternated and soon migrated to watch the winter olympic games in sapporo (1972) on the istrian channel, being able to see gustav thöni win gold in the giant slalom with his yellow skis as the italian flag was raised triumphantly for the awards ceremony. the experience would be repeated more often, with the olympics in munich, the fifa world cup in west germany (1974), the european football championship (1976) and the olympics in montreal (1976). likewise, private broadcasting began in colour (reflected in the broadcaster gbr’s yellow, blue and red initials). the rome-based broadcaster later gained international renown for its footage during the kidnapping of moro, gaining authorisation to enter stadiums and provide live coverage in colour of those games where state television would only be able to maintain some degree of appeal thanks to the replays with carlo sassi in domenica sportiva. through sport, colour provided “real” coverage, with the emblematic example of the sanremo festival: in 1973, the final would be televised by eurovision in colour but could only be captured on foreign television and not by rai repeaters; the following year a fierce telenapoli would offer all three events in colour. soon after the entry into force of the official state colour television, the dichotomy of a picture whose artifice became exposed by colour was finally over, and the colour television was proven to be a key element for the success of the television picture as a “window onto the world”. colour became the central feature when constructing the television picture, which finally displays that supposed transparency which will becomes one of its key elements. following the dissatisfaction of its audience (although one might take the foreign example where the second international french channel ortf chose the opening of the winter olympics from grenoble on 1 october 1967 to inaugurate their own colour broadcasting), rai releases the colour broadcasting of the infamous 1972 summer olympics in munich, where the red shirts of the soviet basketball team overpowering the white jerseys of the us team in the last three seconds of the hotly contested final was even able to stir up excitement among italian viewers. yet, television failed on the real “show”, as the fedayeen’s attack on the israeli athletes would be covered minute by minute by radio reporters directly linked from within the olympic village. conversely, private televisions now commanded the film phenomenon both through companies set up specifically to distribute films to television (such as the rusconi audiovisual system) and through direct agreements with major production houses (as in 1979, berlusconi with fide and titanus). indeed, rai was not only battling over film content, but over being able to offer a real and credible vision of reality: in 1977, the giro d’italia bicycle race was still broadcast in black and white, owing – they say – to the high costs involved in covering such a large event. rai would later be able to address its problems and the crisis of its system, but thanks to colour, the television picture – and with it the same 3504/15 | cultura e scienza del colore color culture and science media identity – would stabilise in a mix of both highly spectacular and everyday events, as a dirty mirror as it was called, which could now fully deploy its effects. the game show is the most mature and conscious platform where, once again, colour plays a central role. the move from tele milano to canale 5, from a small local cable service to the core of the future berlusconi owned network was announced in december 1979 on a game show, i sogni nel cassetto, which only apparently copied rai’s format – with mike bongiorno supported by his most loyal collaborators, such as the notary ludovico peregrini or director lino procacci – and a traditional game mechanism focusing on general knowledge questions. however, as commented by orietta berti in her theme song i sogni son desideri, the prize is making a dream come true (albeit within the “limit” of 20 million lire). no one remembers what the dreams of competitors were, yet there is a clear colour and spatial translation created by the aspirational scenario where nothing is impossible: the tv set builds the communication situation with lights and colours, with a predominance of strong primary colours, and set designs with warm tones as opposed to the icy blue and grey colours of state television in rischiatutto. the set created by graziella evangelista – the unparalleled set designer who would make an unforgettable mark on commercial television, from ok, il prezzo è giusto! to il gioco dei nove and drive in – contained coloured flowers and rainbows, superimposed elements and dazzling psychedelic optical effects. everything came together to make the game show space closer to the fantastic world of the wizard of oz, where reality and dreams, window onto the world and entertainment coexisted – a far cry from rai’s inefficient, sterile, dull, grey cabins and theatre boxes [16]. the new decade began for italian society where this quality of colour television had now become a well-established reality. the first images of the bologna station bombing were shown by private networks in colour, as were the desperate live images from vermicino awaiting an impossible happy ending, the equally innovative coverage of enrico berlinguer’s funeral, the euphoric images of the fall of the berlin wall, the student who was able to stop the tanks in tiananmen, and the chilling scenes that crushed teleological ambitions of the shuttle exploding into a thousand pieces during the festivities in cape canaveral. similarly, in 1980 a television show opens on the glitzy, psychedelic tv set of tele milano 58, shining with thousands of colours, where mike bongiorno cheerfully strides on stage with his programme allegria! bibliography [1]rai radio televisione italiana, annuario 1965, edizione radio italiana, torino 1965. [2] a. lari, sistemi di ripresa e registrazione in rai dal 1950 ad oggi, sandit, albino (bg) 2012. [3] p. ortoleva, telecomunicazioni: un modello italiano?, «memoria e ricerca», n. 5, gennaio-giugno 2000, p. 112. [4]f. andreas, “politique de la grandeur” versus “made in germany”: politische kulturgeschichte der technik am beispiel der pal-secam kontroverse, r. oldenbourg, münchen 2007. [5] a. ronchey, intervista sul non governo. ugo la malfa, laterza, roma-bari 1977. [6] g. crapis, il frigorifero del cervello: il pci e la televisione da ‘lascia o raddoppia?’ alla battaglia contro gli spot, editori riuniti, roma 2002. [7] r.r., tv a colori per le olimpiadi, «corriere della sera», 2 agosto 1972, p. 7. [8] m. mazzanti, l’illuminazione in televisione: manuale per la progettazione e l’uso tecnico/creativo delle luci nello studio tv, quartz color ianiro publishing division, roma 1979. [9] anon., mina. 5 dive in una sola, «bolero film», 777, 25 marzo 1962, pp. 30-32. [10] s. benelli (a cura di), luchino visconti. mina. la donna, e altre cose ancora, «successo», marzo 1962, pp. 60-65. [11] f. pierotti, la seduzione dello spettro. storia e cultura del colore nel cinema, le mani, genova 2012, p. 219. [12] l. goldoni, il “pirolino” che fa scoprire le mille tv private, «corriere della sera», 3 febbraio 1978, p. 14. [13] p. ortoleva, un ventennio a colori. televisione privata e società, giunti, firenze 1995. [14]f. pinto, g. barlozzetti, c. salizzato (a cura di), la televisione presenta… la produzione cinematografica della rai 1965-1975, marsilio, venezia 1988. [15] a. banfi, corso integrale di televisione a colori, con la collaborazione di a. nicolich, n. stucchi, h. salan, d.s. fleming, 8 voll., il rostro, milano 1966. [16] p. valentini, televisione e gioco. quiz e società italiana, archetipo/clueb, bologna 2013 57 color culture and science journal vol. 12 (1) doi: 10.23738/ccsj.120107 color lab ifrj: practical color exercises for fashion courses milena quattrer1, welton fernando zonatti1, anna paula silva gouveia2 1 federal institute of rio de janeiro, belford roxo, brazil. mquattrer@gmail.com, welton.zonatti@ifrj.edu.br 2 university of campinas, campinas, brazil. annagouveia@iar.unicamp.br corresponding author: milena quattrer (mquattrer@gmail.com) abstract this paper is part of a research project called color lab ifrj (laboratório de cor – ifrj, in portuguese) that aims, among other things, to analyze and propose practical color exercises for fashion courses at the federal institute of rio de janeiro – ifrj campus belford roxo. one of the main objectives of color lab ifrj was to develop and to adapt teaching procedures to the campus reality, helping to increase the understanding of color theory concepts for fashion courses. in this sense, two practical exercises called ‘color book’, ‘paper dolls’ and ‘jenifer’s look’ were proposed in order to analyze and to explore the interaction of colors in fashion design. with practical exercises like those, the teacher has taken up important questions of color theory with the students such as color dimensions, color contrast, and chromatic harmonies. these practical exercises provide students with color tools and knowledge that can consciously and objectively be applied in fashion design. keywords color education, color literacy, practical exercises, fashion design, doll received 07 october 2019; revised 25 november 2019; accepted 27 november 2019 color lab ifrj: practical color exercises for fashion courses 58 color culture and science journal vol. 12 (1) doi: 10.23738/ccsj.120107 1. introduction color is a valuable tool for visual artists, stylists, fashion designers, architects, and many others. the analysis of an anonymous questionnaire completed by freshman students of the federal institute of rio de janeiro – ifrj campus belford roxo shows that students find that color theory is important for fashion design projects. however, research shows that the students start attending fashion courses of ifrj campus belford roxo with very superficial knowledge regarding color theory and have difficulty in understanding and differentiating basic concepts of color theory and working with color spontaneously or intuitively (quattrer and gouveia 2018:1). still according to previous research, in brazilian elementary school and middle school, color is treated with less importance when compared to other contents of the art curriculum, which contributes to the perpetuation of conceptual problems in color education (quattrer 2019:83). it should be noted that ifrj campus belford roxo has suffered over the last few years with funding cuts and this has had a negative impact on new campuses such as ifrj campus belford roxo, which is located in one of the poorest areas of the state of rio de janeiro. the lack of physical space and material resources for teaching color theory is a challenge. the ifrj campus belford roxo fashion courses are composed of students of very different ages. for example, some students are still in high school while others have completed high school some forty years ago. in this sense, the teaching experience of the authors, in agreement with hirschler, lopes and oliveira (2011) and bergström (2002), points out that the path to a successful experience on color education in arts and design courses at different levels – high school, graduation, and postgraduation – is to demonstrate to students the intellectual challenge of studying and working with color through practical exercises of investigation and chromatic analysis. therefore, the act of creation is a very important factor for color theory understanding in the ifrj campus belford roxo fashion courses and the creative process is fundamental. 2. objectives the research project called color lab ifrj (laboratório de cor – ifrj, in portuguese) was created in order to analyze and propose practical color exercises for fashion courses of ifrj campus belford roxo and, among other things, to support the cataloging activities of modateca ifrj’s fashion collection. due to the lack of physical space and material resources for teaching color theory at the ifrj campus belford roxo, one of the main demands of color lab ifrj is to develop and adapt teaching procedures to the campus’ reality, which is to help increase the understanding of color theory concepts for fashion courses. 3. method in order to achieve the objectives of the color lab ifrj project and to establish the selection criteria for color theory concepts to be applied in practical exercises of chromatic composition for fashion courses, theoretical support was sought from authors concerned with color education in arts and design: albers (2009), berns (2016), frova (2008), gage (2000), guimarães (2004), monzeglio (1972) and munsell (2019). the practical exercises ‘color book’, ‘paper dolls’ and ‘jenifer’s look’ were structured in order to explore the interaction of colors in fashion design and to collaborate in the fixation of basic concepts of color theory, for example, primary and secondary colors, dimensions of color (hue, value and chroma), color contrast and color harmony. 3.1. color book from the above-mentioned authors and the didactic experiences in color teaching, a practical and individual exercise of research, selection and comparison of color samples of paper, fabric and trims called ‘color book’ was structured and applied to fashion students throughout color theory classes (fig.1). fig. 1: details of students’ color books elaborated with paper and fabric samples and fashion trims in the color theory class, offered in the fashion course of ifrj campus belford in 2018. photo: milena quattrer. color lab ifrj: practical color exercises for fashion courses 59 color culture and science journal vol. 12 (1) doi: 10.23738/ccsj.120107 from the theory of color perception and color contrast, three basic criteria were established for the elaboration of the color book: (i) it should be divided into sections, each intended for one type of material (paper, fabric, trims, etc.); (ii) the pages should be white or black without any lines, since they are the base for gluing the color samples; (iii) and, the color samples of paper and fabric must be the same size and measure at least 2 cm x 2 cm. it should be mentioned that the selection and organization of the color samples is up to the student, who should justify it at the time of evaluation of the exercise. but it is worth saying that students are also instructed to search colors from the contents of color theory studied in each class. and it has proven to be an interesting challenge for them, who often choose to organize color samples based on the dimensions of color (hue, value and chroma) and to construct color palettes from the concepts discussed in class. one of the color palettes commonly elaborated by students is based on warm and cool colors. this distinction refers to the qualification of colors as warm or cool following psychological and cultural interpretations. according to albers (2009:80), in the western tradition, yellow, red, orange, as well as their respective variations are commonly accepted as warm colors. while blue, green and violet, and their respective variations are commonly considered cool. however, such interpretations are relative and a certain color may appear warmer or cooler according to its chromatic composition. for example, a red can be warm or cool depending if the red is tending to yellow or tending to blue. moreover, it is important to point out that the relationship between color and meaning is not arbitrary or accidental, it is part of a cultural context that, according to heller (2014), can be understood from the historical tradition and psychological symbolism. in this sense, according to gage (2000:22), “colors seem ‘warm’ or ‘cool’ only metaphorically.” since, when it comes to the visible spectrum, already studied by the students, wavelengths for blue-violet have the highest warming capacity, while the wavelengths for red have the lowest. if necessary, the teacher can revisit this concept with the students. 3.2. paper dolls a practical exercise with paper dolls and paper samples was structured in order to contribute to the understanding of the concept of chromatic harmony. it is applied in parallel to the color book exercise and before the exercise jenifer’s look. carried out under the supervision of a teacher, students are oriented to develop a color composition for paper dolls based on the concepts of chromatic harmony by affinity and harmony by contrast using only paper samples (fig. 2). fig. 2: details of students’ exercises on color composition with paper dolls elaborated with paper samples in the color theory class, offered in the fashion course of ifrj campus belford in 2019. photo: milena quattrer color harmony by affinity is the coordination of analogous hues or similar color shades. and the opposite of harmony by affinity is harmony by contrast, which refers to the coordination of contrasting hues and/or color shades. these are: (i) black and white contrast; (ii) value contrast; and, (iii) hue contrast. the black and white contrast occurs through the coordination of achromatic or neutral colors (white, black, and their lightness variations (i.e. gray scales). the value contrast concerns combining light and dark colours, i.e., when a saturated hue is coordinated with white, black or gray. finally, the hue contrast refers to the coordination of different hues (one of the strongest of its kind occurs when complementary saturated hues are used, e.g., yellow and violet). this exercise has proven to be very relevant for the teacher to clarify some doubts about the dimensions of color. the teacher revisits the concepts like primary and secondary colors, dimensions of color, and color contrast. these important concepts were presented and discussed previously with features such as: (i) a color wheel of subtractive mixtures adapted from itten (1961), in which the three primary colors magenta, yellow and cyan are used (hue variation), (ii) two scales of value (chromatic and achromatic), and (iii) a chroma scale (saturation variation). especially, it could assist the teacher in explaining the concepts and characteristics of hue and in differentiating monochromatic and achromatic concepts. it is necessary to clarify that in fashion design it is common to use the term ‘monochromatic look’ to refer both to the use of shades of one hue and the use of black, white, and gray only. however, the teaching experience of the authors points out that for teaching purposes it is important to clarify and differentiate the concepts of monochromatic and achromatic. color lab ifrj: practical color exercises for fashion courses 60 color culture and science journal vol. 12 (1) doi: 10.23738/ccsj.120107 so, in ifrj campus belford roxo color theory classes, the term monochromatic look is used only to refer to a set of samples varying in value or saturation but of constant hue. and, the term achromatic is used just to refer to a set of samples varying from white to black through gray – the latter obtained from the mixture of white and black. 3.3. jenifer’s look a practical group exercise with doll's costume design was structured to be applied after the paper dolls exercise in order to explore the interaction of colors in fashion design and to collaborate in reviewing and applying basic concepts of color theory. the exercise was named jenifer’s look (look da jenifer, in portuguese) from the doll’s label used when the exercise was first applied in 2018. at this time, an instagram profile was created to make public on social media the students’ projects (@lookdajenifer) after a student’s request. in order to expand the diversity of bodies and skin colors to reflect the diversity of the ifrj campus belford roxo students, in 2019 barbie® dolls with different skin colors and body types were acquired with the research project funding. carried out under the supervision of a teacher, during the jenifer’s look exercise students are oriented to develop in group a color composition for doll costume design with different types of clothes, footwear and fashion accessories using low-cost materials like fabric samples and fashion trims. the color palette for doll costume design should follow some criteria pre-set by the teacher such as be in line with the previously defined main theme and be based on chromatic harmonies by affinity and/or contrast (fig. 3). at this stage, chromatic harmonies by affinity and/or contrast content has already been studied in previous exercises. fig. 3: students’ color palettes for doll costume design developed using color cards in the color theory class, offered in the fashion course of ifrj campus belford in 2019. photo: milena quattrer. it is also important to point out that color trends content is often previously discussed with students through a chromatic research exercise called ‘moodboard’ that is a simplification of a fashion moodboard commonly used by fashion professionals. in the moodboard exercise the group of students makes use of a system of guiding signs and codes, such as keywords, images, color palette, textures, materials, among other inputs. thus, students are aware of the main color trends in fashion when choosing the color palette. however, for didactic purposes, students are encouraged to investigate chromatic harmonies beyond the color palettes presented by color trend agencies and associations. it is noteworthy that for the jenifer’s look exercise the chromatic composition is more important than the modeling or the quality of workmanship. this is because at this stage some students do not have sufficient knowledge of modeling and sewing. so, the teacher evaluates the students’ progress both as a group and individually from the pre-established criteria: (i) the application of chromatic harmonies (fig. 4) and (ii) the adequacy of composition to the main theme. fig. 4: students coordinating fabrics in gray, yellow and magenta for doll costume design in the color theory class, offered in the fashion course of ifrj campus belford in 2018. photo: milena quattrer. finally, after completing the exercise, students are invited to present their chromatic compositions to other students and the teacher. at this point the student group points out and justifies its choices and the dolls are photographed (fig. 5). it is a substantial moment for the whole class and a moment of reflection on color choices and on metamerism and color inconstancy. color lab ifrj: practical color exercises for fashion courses 61 color culture and science journal vol. 12 (1) doi: 10.23738/ccsj.120107 fig. 5: doll costume design developed by students in 2018 and 2019, in the fashion course of ifrj campus belford. photo: milena quattrer. 4. conclusion color theory classes have been offered as part of ifrj campus belford roxo fashion courses since the second half of 2017. from the analysis of the students’ midterm exams (mv1) and final exams (mv2) over the last two years, it was possible to reassess and change the didactic sequence of the pratical exercises color book, paper dolls and jenifer’s look. as said earlier, students start attending fashion courses of ifrj campus belford roxo with very superficial knowledge regarding the color theory, and the lack of physical space and material resources for teaching color theory is a challenge. in this sense, color book, paper dolls and jenifer’s look have proven to be an important didactic resource for discussing in a playful way relevant questions and concepts about color theory, such as color dimensions, color contrast, and types of chromatic harmony. moreover, exercises like these have been shown to be very attractive and thought provoking for students. with the help of these exercises, students are consciously and objectively trained to perceive how color is an important resource in fashion design. 5. conflict of interest declaration the authors declare that there is no conflict of interest regarding the publication of this paper. 6. funding source declaration this research was supported by programa institucional de incentivo à produção científica, tecnológica e artísticocultural (prociência) of federal institute of rio de janeiro (ifrj). 7. acknowledgements we thank our colleague amanda olívia silva from ifrj campus belford who greatly assisted the students in modeling and sewing. 8. short biography of the authors milena quattrer phd in arts (2019) at university of campinas, ia unicamp, campinas, brazil). master of arts (2013) at university of campinas, ia unicamp. bachelor in fine arts (2008) at university of campinas. professor at federal institute of rio de janeiro, brazil. research topics: color education; color in information design; art education. welton fernando zonatti postdoc in reuse and textile recycling (2017) at university of são paulo, usp. phd in sustainability (2016) at university of são paulo, usp, master's degree in materials and textile processes (2013) at university of são paulo, usp. bachelor in textile and fashion (2008) at university of são paulo, usp. bachelor in arts (2017) at centro claretiano. professor at federal institute of rio de janeiro, brazil. research topics: textile color lab ifrj: practical color exercises for fashion courses 62 color culture and science journal vol. 12 (1) doi: 10.23738/ccsj.120107 technology, fashion ecodesign, materials/processes for reuse and textile recycling. anna paula silva gouveia architect (1986) and phd (1998) in architecture and urbanism at the university of são paulo, fau usp. professor at the university of campinas, unicamp, brazil in undergraduate and postgraduate courses in visual arts and graduation in architecture and urbanism. research topics: project and teaching methodology; color and typography applied to the urban landscape; art-jewelry. references albers, j. (2009) a interação da cor. são paulo: martins fontes. bergström, b. (2002) ‘creative colour education’, aic 2001, proceedings of the 9th congress of the international colour association chung r. y. and rodrigues a. b. j. (eds.) bellingham, wa: spie, 4421, pp. 963–966. berns, r. s. (2016) color science and the visual arts: a guide for conservators, curators, and the curious. los angeles: getty publications. frova, a. (2008) luce, colore, visione: perchè si vede ciò che si vede. milano: bur scienza. gage, j. (2000) color and meaning: art, science, and symbolism. berkeley: university of california press. guimarães, l. (2004) a cor como informação. são paulo: annablume. heller, e. (2009) psicología del color. cómo actúan los colores sobre los sentimientos y la razón. barcelona: gustavo gili. hirschler, r., lopes, l. c. and oliveira, d. f. (2011) ‘light and colour in the classroom: demonstrations from physics to the interaction of colours’, aic 2011 interaction of colour and light, proceedings of the midterm meeting of the international color association, schindler v. m. and cuber s. (eds.) zurich: pro/colore, pp. 169–172. itten, j. (1961) the art of color: the subjective experience and objective rationale of color. new york: reinhold. monzéglio, e. (1972) interpretação do significado de módulo/cor: contribuição ao estudo da cor e sua aplicação na programação de mensagens visuais. ph.d diss., university of são paulo. munsell color blog (2019). how color notation works. available at: https://munsell.com/about-munsell-color/how-color-notation-works/ (accessed: 25 november 2019). quattrer, m. (2019) a cor no livro didático de arte. ph.d diss., universidade estadual de campinas, instituto de artes, campinas, sp, brazil. quattrer, m., and gouveia, a. p. s. (2018) ‘exercises of chromatic investigation and analysis on color education’, color research and application 43(6), pp. 851– 856. doi.org/10.1002/col.22282. 79 color culture and science journal vol. 13 (1) doi: 10.23738/ccsj.130209 quick gamut mapping for simplified color correction matteo cereda 1 , alessandro rizzi 1 , alice plutino 1 1 department of computer science, university of milan, milan, italy. cereda.matteo95@gmail.com, alessandro.rizzi@unimi.it, alice.plutino@unimi.it corresponding author: alice plutino (alice.plutino@unimi.it) abstract this paper presents an alternative simplified method to convert color spaces more quickly than using the traditional gamut mapping. the conversion is carried out in the two-dimensional xy chromaticity diagram, through an affine transformation, which remaps the color chromaticity only. the affine transformation applies to the colors of the original image the values obtained by solving two linear systems of three equations using the coordinates of the input and output color spaces. then, these values are applied to each xy coordinate of the image color obtained from its rgb values. purpose of this alternative method is not the colorimetric accuracy, but testing is an oversimplified version can lead to acceptable results. in image and video editing, the steps of color correction and color grading are often performed by the expert’s eye using various image editing tools and software. this approach overshadows the colorimetric aspect, focusing just on the aesthetic enhancement. the proposed alternative gamut mapping method, named quick gamut, will be presented through application examples. keywords (gamut mapping, color correction, image processing, digital image, colorimetry) received 01/03/2021; revised 02/04/2021; accepted 07/04/2021 mailto:cereda.matteo95@gmail.com quick gamut mapping for color correction 80 color culture and science journal vol. 13 (1) doi: 10.23738/ccsj.130209 1. introduction when talking about color reproduction in digital systems it is fundamental to define the concept of color gamut. a color gamut is the set of colors that can be reproduced by a specific device (e.g., monitor, printer, photographic film). each device or media has a different color gamut, so the colors that we see in a monitor cannot be reproduced by a printer or by a different kind of monitor. a common way to compare different color gamut is through the x y coordinates of the cie 1931 chromaticity diagram. as defined in (ramanath, 2014): “gamut mapping refers to the process of translating colors in one device’s color space to that of another. this process is performed on colors in images and video so as to create a rendition of a source image (typically in a capture device’s color space) in an output device’s color space while meeting several rendering intents: absolute and relative colorimetric fidelity, perceptual accuracy, and the problem of saturation – each of which trades off one color property at the expense of another”. since gamut mapping is a current open issue in computer science and color analysis, through the history different methods and approaches to perform it have been proposed and this issue has been recognized also by cie (commission internationale de l’éclairage), which set up the technical committee 8-03 on gamut mapping. the state of the art on gamut mapping is really wide and complex, therefore in this work we will not report a survey or a technical comparison among gamut mapping methods, anyway we suggest the works proposed in (morovič, 2001) and (morovič, 2008) for a detailed survey on gamut mapping techniques. in general, the traditional methods of automatic color spaces conversion and gamut mapping from a device to another are colorimetrically accurate, but in some cases the result is not perceptually satisfactory, and it needs to be edited manually. in this paper, we present an alternative method that implement an oversimplification of the classic gamut mapping approach. in contrast to traditional gamut mapping, the proposed method applies a geometric simplification, which consists in mapping the colors only in the two-dimensional cie xy chromaticity diagram and applying an affine transformation that remaps colors chromaticity (wolf, 1961). in this paper, we propose some preliminary experiments and applications of this method, called quick gamut on some images, to assess if the decrease of computational complexity (which becomes linear) could provide satisfactory results. 2.1 affine transformation quick gamut uses an affine transformation based on the following formula (weisstein, 2002): { 𝑋 = 𝑎𝑥 + 𝑏𝑦 + 𝑒 𝑌 = 𝑐𝑥 + 𝑑𝑦 + 𝑓 (1) where, x and y are the coordinates of the new color space (output) and x and y are the old coordinates (input). before applying the transformation, it is necessary to know a, b, e, c, d and f values. these values can be obtained by solving two linear systems of three equations, one for x and the other for y, using the coordinates of the three fundamental components of the input and the output color spaces. { 𝑋𝑟 = 𝑎𝑥𝑟 + 𝑏𝑦𝑟 + 𝑒 𝑋𝑔 = 𝑎𝑥𝑔 + 𝑏𝑦𝑔 + 𝑒 𝑋𝑏 = 𝑎𝑥𝑏 + 𝑏𝑦𝑏 + 𝑒 (2) { 𝑌𝑟 = 𝑐𝑥𝑟 + 𝑑𝑦𝑟 + 𝑓 𝑌𝑔 = 𝑐𝑥𝑔 + 𝑑𝑦𝑔 + 𝑓 𝑌𝑏 = 𝑐𝑥𝑏 + 𝑑𝑦𝑏 + 𝑓 (3) after the values computation from the previous systems, it is possible to map each pixel of the image from the original color space to the output color space by applying formula 1. 2.2 quick gamut mapping in order to map the colors of the original image in the new color space, it is necessary, at first to convert the input rgb values into x and y chromaticity coordinates then, apply the affine transformation and at the end convert the new x y coordinates into rgb values. the steps to apply quick gamut mapping are listed below: 1. normalize the rgb values over [0, 1]; 2. perform the gamma correction (i.e., raise each normalized value to gamma); 3. multiply the color space transformation matrix by the rgb vector; the product between the transformation matrix and the rgb vector is shown below: [ x 𝑌 𝑍 ] = [𝑀] [ 𝑅 𝐺 𝐵 ] (4) where, m is the transformation matrix given by: quick gamut mapping for color correction 81 color culture and science journal vol. 13 (1) doi: 10.23738/ccsj.130209 [ 𝑋𝑟 𝑋𝑔 𝑋𝑏 𝑌𝑟 𝑌𝑔 𝑌𝑏 𝑍𝑟 𝑍𝑔 𝑍𝑏 ] (5) the transformation matrix varies according to the color space (i.e., adobe rgb (1998), srgb). 4. the values obtained from the above multiplication have range [0, 1] and are mapped in the xyz color space. 5. convert the xyz values into xyz coordinates with the formulas: 𝑥 = 𝑋 𝑋 + 𝑌 + 𝑍 (6) 𝑦 = 𝑌 𝑋 + 𝑌 + 𝑍 (7) 𝑧 = 𝑍 𝑋 + 𝑌 + 𝑍 (8) in this case, it is enough to know only the x and y coordinates because we are working on a twodimensional space. 6. apply the affine transformation to the obtained xyz coordinates (formula 1); 7. map all the pixels in the image to the output color space with the affine transformation and convert the new coordinates back to xyz values using the formulas: 𝑋 = 𝑥 𝑦 𝑌 (9) 𝑌 = 𝑌 (10) 𝑍 = 1 − 𝑥 − 𝑦 𝑦 𝑌 (11) 8. normalize and clamp the cie xyz values in the range [0, 1]; 9. convert cie xyz values to rgb color space using the inverse transformation matrix: [ 𝑅 𝐺 𝐵 ] = [𝑀−1] [ x 𝑌 𝑍 ] (12) 10. apply the gamma factor (rising the rgb values to 1 / γ), and multiply the values by 255 to bring them back into range [0,255]; 11. clamp all the rgb values into the range [0, 255]. 2.3 example of quick gamut mapping applications in the examples that will be shown, the srgb coordinates are obtained by a linear transform with the matrix reported in formula 13 and the inverse transformation matrix in formula 14 (anderson et al., 2020). 𝑀 = [ 0.4124564 0.3575761 0.1804375 0.2126729 0.7151522 0.0721750 0.0193339 0.1191920 0.9503041 ] (13) 𝑀−1 = [ 3.2404542 −1.5371385 −0.4985314 −0.9692660 1.8760108 0.0415560 0.0556434 −0.2040259 1.0572252 ] (14) new rgb color space r x 0.4 y 0.35 g x 0.3 y 0.4 b x 0.27 y 0.24 white x 0.3093 y 0.3260 tab. 1 color space specifications. fig. 1 input and output rgb color spaces. quick gamut mapping for color correction 82 color culture and science journal vol. 13 (1) doi: 10.23738/ccsj.130209 in figure 1 is reported an image of a typical input rgb color space (srgb) and the destination color space computed using quick gamut mapping (see table 1). to show the performances of quick gamut applied on an image, in figure 2 is reported a comparison between an image mapped using photoshop and an image mapped using our method. here, it can be seen that quick gamut offers a perceptually satisfactory result without loss of details, in contrast to photoshop that produce images with flat colors. 2.4 quick gamut mapping assessment to evaluate the precision of quick gamut conversion, we tested this method on a colorchecker (figure 3). in table 2 are reported the cie l*a*b* values of every patch of the colorchecker after a gamut mapping performed using photoshop and using quick gamut. the differences between cie l*a*b* values have been computed using δe* difference (mokrzycki and tatol, 2020). since quick gamut provides a strong geometrical simplification to map the color values in a new space, the color difference δe* is high for some patches. nevertheless, the linearity of the affine transform makes this method particularly easy to compute. fig. 3 (left) quit gamut mapping application, (centre) original image and (right) gamut mapping performed through photoshop. fig. 2 colorchecker. quick gamut mapping for color correction 83 color culture and science journal vol. 13 (1) doi: 10.23738/ccsj.130209 colore photoshop quick gamut mapping δ l* a* b* l* a* b* δl* δa* δb* δe* 1 38 8 11 37 4 5 -1 -4 -6 7.28 2 64 11 15 64 8 6 0 -3 -9 9.48 3 53 5 -18 50 3 -6 -3 -2 12 12.53 4 46 -8 14 44 -1 6 -2 7 -8 10.82 5 56 9 -23 55 6 -6 -1 -3 17 17.29 6 74 -17 4 72 -3 -1 -2 14 -5 15.00 7 58 19 22 59 12 17 1 -7 -5 8.66 8 55 13 -27 40 6 -13 -15 -7 14 21.68 9 52 27 11 46 14 6 -6 -13 -5 15.16 10 35 11 -17 30 7 -6 -5 -4 11 12.73 11 82 -11 22 73 -4 16 -9 7 -6 12.88 12 71 5 22 69 8 20 -2 3 -2 4.12 13 49 12 -25 31 5 -12 -18 -7 13 23.28 14 62 -19 16 56 -7 9 -6 12 -7 15.13 15 45 26 17 37 16 9 -8 -10 -8 15.09 16 84 -6 23 80 3 23 -4 9 0 9.85 17 59 22 -12 47 15 -5 -12 -7 7 15.56 18 60 0 -15 53 0 -9 -7 0 6 9.22 19 97 -1 2 97 4 2 0 5 0 5.00 20 81 -1 0 82 5 1 1 6 1 6.16 21 67 0 0 67 4 1 0 4 1 4.12 22 51 0 0 51 3 1 0 3 1 3.16 23 36 0 -1 36 2 0 0 2 1 2.24 24 22 0 -1 22 2 0 0 2 1 2.24 tab. 2 cie l*a*b* values obtained from figure 3. highlighted in green the values between 0 and 2.99, in yellow the values between 3 and 4.99, in orange the values between 5 and 9.99, in blue the values greater than 10 3. conclusion in this work, quick gamut, an alternative simplified gamut mapping method has been presented. this method works only on the two-dimensional chromaticity information of the color spaces involved. the preliminary tests carried out in this work, showed that despite the high color differences between the images obtained with traditional gamut mapping and with this method, the new proposed method can be use to provide a quick transformation for the color correction of images and/ or videos. 4. conflict of interest the authors declare no conflict of interest. 5. declaration of funding sources the authors received no specific funding for this work. 6. short biography of the authors matteo cereda – he graduated in computer science for digital communication at the university of milano. as a great passionate of digital videos and photos, during his university experience he chose to deepen the multimedia field. this allowed him to gain skills in video and image processing, image enhancement and color correction. alice plutino – she recently obtained the phd at the department of computer science, university of milano. her research interests are: colorimetry, image processing, data digitization and archiving with a particular interest in applications on film restoration. she is author of many scientific works, member of the organizing committee of aic2021 and part of different workshops and conferences. alessandro rizzi – he is full professor at the department of computer science at the university of milano, teaching multimedia, colorimetry and film restoration. he is doing research since 1990 in the field of digital imaging with a particular interest on color, visualization, photography, hdr, vr and on the perceptual issues related to digital imaging, interfaces, quick gamut mapping for color correction 84 color culture and science journal vol. 13 (1) doi: 10.23738/ccsj.130209 and lighting. he is co-chair of the is&t conference “color imaging: displaying, processing, hardcopy and applications”, topical editor for “applied color science” of the journal of optical society of america a, associate editor of journal of electronic imaging, member of several program committees of conferences related to color and digital imaging, and author of about 400 scientific works. references anderson, m., motta, r., chandrasekar, s., and stokes, m. (1996) 'proposal for a standard default color space for the internet srgb', color imaging conference. mokrzycki, w. and tatol, m. (2011) 'color difference delta e a survey', machine graphics and vision. 20. pp. 383-411. morovič, ján. color gamut mapping. vol. 10. john wiley & sons, 2008. morovič, ján, and m. ronnier luo. "the fundamentals of gamut mapping: a survey." journal of imaging science and technology 45.3 (2001): 283-290. ramanath r., drew m.s. (2014) gamut mapping. in: ikeuchi k. (eds) computer vision. springer, boston, ma. https://doi.org/10.1007/978-0387-31439-6_456 weisstein, e. (2002) crc concise encyclopedia of mathematics, second edition. 2nd edn. new york: chapman and hall/crc, p. 36. wolf, e. (1961) progress in optics. 1st edn. amsterdam: north-holland pub. co., pp. 213-214. 16 colour culture and science journal vol. 12 (2) doi: 10.23738/ccsj.120202 περὶ χρωμάτων (peri chrōmatōn): colour formation and investigation method. maria fernanda ferrini1 1department of humanities, macerata, italy corresponding author: maria fernanda ferrini (maria.ferrini@unimc.it) abstract in this essay, the attention is focused on the method used to investigate colours, as produced in nature. this method was proposed by the author of the treatise peri chrōmatōn, which has become part of the corpus aristotelicum. the colours are first divided into two large categories, simple and mixed, in accordance with other scientific and philosophical approaches. simple (primary) colours are considered to be white and yellow, and are associated with the elements (air, water, earth, and fire/sun); black is also associated with the elements as they transform into one another. this division is new in comparison with previous theories based on two or four fundamental colours. the endless range of colours seen in objects, plants and animals, is connected to the mechanisms of mixing different qualities and quantities, inherent in what it comes into contact with, and in the consequent changes, in conditions and states of matter, in the incidence of light, qualitatively and quantitatively different. the heuristic reference scheme and the analogical model are represented by the dyeing process. the essentially phenomenological treatise contains historically significant insights: no colour can be seen in its purity; the reciprocal interaction of colours; the variability of conditions that determine the chromatic impression; light as a component of mixtures, and its diversity depending on the source; and the chromatic value of shade. in it, we can also see the formation of a classification of colours and a nomenclature, founded on the relationship of distinct chromatic notations with light and darkness. keywords colours and elements, lights and pigments, shadow and darkness, physis and technē, dyers and painters. received 24/10/2019; revised 03/01/2020; accepted 26/06/2020 περὶ χρωμάτων (peri chrōmatōn): colour formation and investigation method. 17 colour culture and science journal vol. 12 (2) doi: 10.23738/ccsj.120202 1. introduction the topic of perception, classification and naming of colours in greek culture is at the centre of a lively debate, which started as early as antiquity. the bibliography on the subject is vast and includes studies in various fields (philological, anthropological, sociological, psychological, philosophical, artistic) and stimulating comparative investigations (ferrini 1999; 2008; 2010; 2019; gage 2001; tiverios and tsiafakis 2002; cleland and stears 2004; rouveret et alii 2006; carastro 2009; grandclément 2011). an essential work to capture some of the most salient aspects of greek speculation on colour is περὶ χρωμάτων incorporated in the corpus aristotelicum: this treatise is the only ancient work dedicated exclusively to colours (observed in objects, plants and animals) and has been preserved in its entirety, despite some textual corruptions. 2. simple colours in peri chrōmatōn, colours are divided into two large groups, simple and mixed, in accordance with other scientific and philosophical treatises. these demonstrate the close link, in greece, between the investigation of the cosmos and the origin of the existing, and the theory of colour. simple colours (which we would call primary) are regarded as white (τὸ λευκόν) and yellow (τὸ ξανθόν): these are associated with the elements (air, water, earth, fire/sun); black (τὸ μέλαν), as a colour, is also associated with the elements, although when they change into each other: «simple are those colours that are associated with the elements, i.e. fire, air, water, earth: air and water are white by nature, fire and sun are yellow. the earth is also white by nature but appears to be various colours because it is tinted. [...] the colour black is associated with the elements when they are transformed into one another. other colours derive from these, as can easily be seen, by combining and mixing with each other. darkness, in the end, is due to the lack of light» [1]. defining black as a colour that is connected with the elements in their respective transformation has original characteristics in greek literature; it derives from the observation of the phenomena described from time to time, in which processes that imply gradual changes over time take place: the appearance of black occurs over time. furthermore, black is not only a colour but also a state of darkness or semi-darkness. it is particularly significant and original the passage which examines the three ways black can appear: as a positive colour, associated with the elements, and as a negative colour, in that it is the total or partial lack or absence of light, and is connected with a visual weakness or insufficiency. the black of black objects is distinguished from the black that is shown when an object reflects no or little light. in addition, terms connected with the noun that indicates shadow (σκιά, distinct from darkness, σκότος, which is deprivation of light) are used for the first time with a specifically chromatic value ('shadow colour'): «in three ways black appears to the eye. in general, what we do not see is black by nature (because all objects of this colour reflect like blacklight), or those objects from which no light reaches the eyes are black: what we do not see if the surrounding space is visible, determines the appearance of black; or, finally, all those objects from which light reflects poorly and very faintly appear black. this is why even shadows appear black; and so also does water, when it is disturbed, as when the sea ripples: since, due to the agitation of the surface, few rays fall on it and the light is diffused, what is in shadow appears black. the cloud also appears black for this same reason, whenever it is very dense. the same happens to water and air when light does not penetrate it completely [...]. it is not difficult to understand from many factors that darkness is not a colour, but deprivation of light, in particular from the lack of perception of how great the darkness is, and what its form may be, as is possible for other visible objects» [2]. black, therefore, occupies a very special place: it is the only colour which, while having the function of a primary colour, can be produced and manifest itself over time. even the definition of white and yellow as simple colours has new features compared to other and previous theories, in which white and black are considered simple, explicitly or implicitly, or four colours, white, black, red and yellow/green: red is the salient colour par excellence, while yellow and green are additional colours in many cultures, being able to integrate a triadic base, consisting of white, red, and black/blue. the fourcolour painting, of which there is evidence in some ancient sources, is a matter of debate; in any case, it may have been influenced by conceptions of the cosmos and the elements. the relationship between colours and elements is theoretically investigated in other greek sources, while in peri chrōmatōn it is an accepted fact, instrumental to the discussion and a constant point of reference: each physical element is associated by its nature with a colour, as its inherent and characteristic, distinctive quality. secondary and tertiary colours are obtained by mixing and in certain quantitative and qualitative [3] ratios. few other colours are listed as ingredients in addition to the primary colours, while light and sun rays appear as fundamental components, quantitatively and qualitatively marked in their various gradations, intensities, and inclinations. observations on light constitute one of the most significant aspects of this treatise. even its opposite, darkness, has direct and concrete effects on the production and appearance of colours, as well as shadow, which has a chromatic value, and which can vary in intensity and be a περὶ χρωμάτων (peri chrōmatōn): colour formation and investigation method. 18 colour culture and science journal vol. 12 (2) doi: 10.23738/ccsj.120202 component of the mixture from which colours originate. these observations seem very important, if one thinks of the history of painting from antiquity to the present, the problem of the representation of shadow and the function attributed to it in theoretical speculation and practice. 3. the infinite variety of colours and the investigation method the variety of colours is linked to mixing mechanisms of different qualities and quantities, which are inherent to what comes into contact, and to the consequent changes, to conditions and states of matter, to the incidence of light: «the multi-faceted aspect and the infinite variety of colours must not escape attention, no matter for how many reasons this may happen. we will discover the cause, either in their unequal and discontinuous reception of light and shadows [...], or in the fact that the mixed colours differ in quantity and vividness of the components, or that they do not have the same proportions. violet, red, white and any other colour differ greatly according to the plus and minus, by the respective combination and purity. the colour mixed according to whether it is bright or shiny, or on the contrary dull and opaque, contributes to the difference. the brightness is nothing if not continuity and density of light; in fact, the colour gold shines when the yellow of the sun's light, which is very concentrated, shines through. consequently, the neck of pigeons and droplets of water also appears gold-coloured if there is a reflection of light» [4]. 3.1 reference models both the heuristic reference scheme and the analogical model are shown by the fabric dyeing process, extending to other phenomena. each body is as if immersed in a dye: the image of a liquid flowing through the material is frequently used, conveying its chromatic qualities, spreading out along its path and permeating the parts that are porous enough to absorb it. to carry out the process, the following is necessary: a dye that penetrates the pores of the object to be dyed, water as a medium and heat. in particular, the development of different colours when dyeing with the murex illustrates what happens with fruits, which take on various colours, depending on their ripening stages: «when they crush the murex and drain the moisture away, and then it is poured into pots and boiled, initially no colour is distinguishable in the dyeing bath. this is because each of these colours gradually varies in many different ways; the more the liquid boils, the more the colours that remain are combined: you have black, white, brown, blue-grey, and then all the colours become violet once they have been boiled together, so that none of the other colours is distinguishable by itself, due to the mixture» [5]. dyeing practices are used as experimental evidence and as an explanatory model of what happens in nature, according to parallels traditionally established between natural processes and technē procedures, and helpful for reasoning as the latter are useful for understanding and interpreting the former. therefore, art can represent a model for the analysis of nature. however, in peri chrōmatōn, it is noted that while the dyeing technique performs this function, the mixture of pigments by painters is not considered methodically valid for the investigation of colours. it is, in fact, the dyers who imitate nature, not the painters. on the contrary, the dyeing bath of fabrics soaked in the dyeing substance resembles how the liquids present in plants and animals affect and colour their various parts. 3.2 colour mixing in nature the author of peri chrōmatōn proposes a method of investigation of colours, just as they are produced in nature, referring repeatedly to certain criteria that essentially derived from a series of observations arranged and supported by rules, from specialised knowledge, and based on the conviction that in nature lights and not pigments are mixed. «we must examine all this without mixing these colours as painters do, but by comparing the rays that are reflected by the colours we have been talking about: this is the best way to investigate the mixtures of colours according to nature. also, the evidence and basis for comparison must be derived from cases where the origin of the colours will be clear. this is particularly true of sunlight and firelight, air and water: their mixture in greater or lesser proportion gives rise to almost all colours. […]. other colours must then be observed in the processes of ripening since they are produced in plants, fruits, hair, feathers and so on».[6] the skill of painters, who mix pigments, is opposed to the recommended research method, which is to observe colours in nature. the emphasis is placed on the concept expressed by the nexus kata physin theōrēsai [7]. the passage was usually compared with the statement of aristotle, in the meteorologica (372a 5 ff.), about the three main colours (red φοινικοῦν, green πράσινον, violet ἁλουργόν) of the rainbow, which cannot be artificially produced by painters: in both cases, it seems that the authors distinguish between two systems, which we define respectively as an additive, where coloured lights are mixed, and subtractive, where pigments are mixed. 3.3 origin and change of colours careful observation and correlation of the phenomena would be more fruitful in cases where colours' origin is clear (those in which sunlight and fire, air and water interact): then they can be valid as proof and as a basis for comparison. the reference to a colour of clear origin, the περὶ χρωμάτων (peri chrōmatōn): colour formation and investigation method. 19 colour culture and science journal vol. 12 (2) doi: 10.23738/ccsj.120202 comparison of reflected rays and the effects of light on different objects, the transition from one colour to another, and again (as the author says in the section on the formation of colours in the vegetable and animal world) the connection between colour in living organisms and ripening represent the basis for the study and understanding of chromatic phenomena. in this way, everything can have a permanent colour and a transitory colour, an original colour and a colour that is formed over time, again starting from the original, linked to the element of which a substance is predominantly made up. the only distinction that the author invites us to make is between the colour based on observation, or presupposition, and the colour that occurs in successive phases of growth (plants and animals reach their own colour as they mature), or in dyeing processes, or following mechanical phenomena, for example, the rubbing of stones and metals, physical (and chemical) actions due to light and heat. we can, therefore, observe initial colours, intermediate colours, final colours; light is a fundamental variable for their formation and their manifestation, even transitory. there is a colour naturally linked to things, as they are mainly formed by an element, but we do not always see it; therefore analysis and interpretation focus on the visible and very mutable colour, on the colour that appears at the beginning of a process, for example, green in plants. the evidence (πίστις) that proves and confirms the validity of the statements once again comes from observation and experience. the simultaneous reference both to arguments that can be adduced as evidence and to a criterion by which relationships between things are identified (the criterion of similarity) is significant. in collecting data, attention is paid to the analogy of the phenomena and the causes that produce them. the necessity to observe and correlate the phenomena, underlined many times, is associated with an attempt at experimentation in the passage in which reference is made to the iridescent neck of the pigeons, an example that is added to the chromatic changes of the air and water, due to the different incidence of light on a surface: «[...] the air sometimes takes on a purple tint to the east and west, when the sun rises and sets: then its particularly weak rays hit the dark air. the sea also tends towards the purple when the waves rise and the part of the wave that arches is in shadow, for the sun's rays strike this inclined part lightly, and cause the violet colour to appear. this is also observed in the plumage of birds: under a certain angle of light, it has a violet colour. if a lesser amount of light hits it, it is of that dull colour which is called brown; whereas plenty of light, mixed with the original black, produces red. if it is bright and glittering, the colour changes into the red of the flame» [8]. the orientation of the feathers in the direction of the light, almost skimming, has several effects that depend not only on the quantity and quality of the incident light but also on the angle of incidence. it is significant that the plumage of birds, traditionally a symbol of colour variation, is colouristically defined as the iridescent seawater. the iridescent colour of pigeons' neck, in the sun, was one of the well-known arguments in favour of relativism of knowledge and optical illusions (today we would speak of colouring by interference). each qualitative and quantitative change corresponds to a change of colour and a step to characteristics that from time to time are opposite or intermediate, with respect to the completion of a process and the time it takes. the processes and actions that influence the various production of colours are heating, combustion, liquefaction, melting, boiling (in the case of artificial dyeing, for example), cooling, maturation/cotion (in plants and animals), correlated with nutrition and assimilation. precise qualities, positions and dispositions, characteristics and states of matter are just some of the variables that determine colour: density and compactness, rarefaction and thinness, porosity or continuity, smoothness or roughness. different conditions related to light and shadow, depth, distance, surface or interior vision, direct or through a medium, permanence or movement, space or time, add to the list of factors to which reference is made several times. the various causes of colour change are therefore attributable to physical (or chemical, in some cases, from our point of view) characteristics and processes, and to optical phenomena of light reflection, sometimes superimposed. 3.4 no colour is seen in its purity attention is constantly drawn to the infinite variety of colours [9]: this part is extremely interesting for its modernity. there is a clear awareness of characteristics, colour attributes, distinctions and phenomena, to which we give precise names (hue, saturation, brightness, contrast of tone, simultaneous contrast of colours, influence of the field) and which we define with different parameters, based on acquisitions and new settings, methodical experimentation and instrumental measurements, but in their intuitive essence are present in the mind of our author. no colour can be seen in its purity: all are to some extent modified by mixing if not with other colours, certainly with light and shadow. in fact, light and shadow appear to be the main factors of chromatic alteration: they can vary in intensity, quantity, regularity and interact differently with things that have a different composition, structure, consistency, surface, position, exposure and inclination: «we do not see any colour in its purity, as it is in reality, but all mixed with others: and even when they are not mixed with another colour, they are at least mixed with the rays of light and shadows; so they appear different, and not as they are. for the same reason, the same objects appear to us of a different colour when observed in the περὶ χρωμάτων (peri chrōmatōn): colour formation and investigation method. 20 colour culture and science journal vol. 12 (2) doi: 10.23738/ccsj.120202 shadow, in the light, when there is the sun, under intense or dim light, according to inclinations and different positions, and other different factors. the same happens with objects exposed to the light of a fire, the moon, or lanterns because each of these lights is different; and again in the case of the combination of colours, because they acquire their colour as one passes through the other. when light, falling on something, is coloured, and becomes, for example, red or grass green, and then the reflection falls on another colour, it takes on a different chromatic mixture as a result of this new intermingling. undergoing these continuous but imperceptible modifications, the light sometimes reaches the eyes already mixed with many colours, but in such a way as to determine, among the prevailing colours, the perception of only one. this is why objects observed underwater come closer to the appearance of water, and objects observed in mirrors have similar colours to those of the mirrors themselves. the same must be thought to happen with the air. in conclusion, all colours are a combination of three components: light, the medium through which it is seen, for example water or air, and finally, the basic colours from which light is reflected. » [10]. 4. conclusion there are many historically significant findings in this treatise, which is essentially phenomenological: no colour can be seen in its purity; the mutual interaction of colours; the variability of conditions that determine the chromatic impression; light as a component of mixtures, and its diversity depending on the source; the chromatic value of shade. likewise, the attempt at a classification of colours and nomenclature, based on the relationship of distinct chromatic notations with light and darkness, emerges in it. 5. conflict of interest declaration no potential conflict of interest 6. funding source declaration university research funds 7. short biography of the author maria fernanda ferrini is associate professor of greek language and literature at the university of macerata. her principal monographies are focused on the technical and scientific treatises of the corpus aristotelicum (de coloribus, problemata, physiognomonica, de audibilibus, mechanica, de plantis, rhetorica ad alexandrum). among her most recent publications is χρωματα (chrōmata). lessico dei termini greci di colore. i: alpha (2019) notes [1] col. (= de coloribus) 791a 1-12. the greek text of the treatise is quoted according to my edition (ferrini 1999), for which i revised the manuscripts collated by bekker (1831) and by prantl (1881), and i used other manuscripts that were not examined by the other two editors. [2] col. 791a 13-b 6. [3] col. 792a 4-5; 792 a 32-b 2. for some derivatives colours, components and quantity are given, but this is only vaguely indicated with ‘a lot’ and with ‘a little’, ‘more’ and ‘less’; in every case, the author does not give formulae (his treatise is not an investigation for practical purposes) which we find in a list of instructions for the composition of colours, destined for painters and dyers, which was very common from late antiquity until the modern age, as a jealously guarded secret of every workshop, painting school, and alchemy and weaving studio. [4] col. 792b 33-793a 16. [5] col. 795b 11-21; cfr. 797a 3-8. [6] col. 792b 16-32. [7] col. 792b 20 κατὰ φύσιν θεωρῆσαι, ‘investigate according to nature’. the method proposed is the best and most effective for explaining the variety of colours, even according to the more general principle, typical of ancient science, of studying phenomena as they appear in nature. [8] col. 792a 17-29. [9] col. 792b 33-34: τὸ πολυειδὲς καὶ τὸ ἄπειρον τῶν χρωμάτων. [10] col. 793b 12-794a 2. references bekker, i. (1831) aristoteles graece. volumen alterum. berolini: apud georgium reimerum. carastro, m. (2009) l’antiquité en couleurs. catégories, pratiques, representations. grenoble: jérôme millon. cleland, l. and stears, k. (2004) colour in the ancient mediterranean world. oxford: alden press. ferrini, m.f. (1999) pseudo aristotele i colori. edizione critica, traduzione e commento. pisa: ets. ferrini, m.f. (2008) [aristotele] i colori e i suoni. milano: bompiani. ferrini m.f. (2010), ‘colori della natura e colori dell’uomo (friedrich nietzsche, morgenröthe 426)‘, in bertolini, s. (ed.) apollineo e dionisiaco prospettive e sviluppi con nietzsche e oltre nietzsche. roma: aracne, pp. 19-32. ferrini, m.f. (2019) χρωματα chrōmata lessico dei termini greci di colore i: alpha. macerata: eum. gage, j. (2001) colour and culture. practice and meaning from antiquity to abstraction. singapore: thames & hudson. grand-clément, a. (2011) la fabrique des couleurs. histoire du paysage sensible des grecs anciens (viiie – début du ve s. av. n. è). paris: de boccard. prantl, c. (1881) aristotelis quae feruntur de coloribus de audibilibus physiognomonica recensuit carolus prantl. lipsiae: in aedibus b.g. teubneri. rouveret, a., dubel, s. et naas, v. (2006) couleurs et matières dans l’antiquité. textes, techniques et pratiques. paris: éditions rue d’ulm. tiverios, m.a. and tsiafakis, d.s. (2002) color in ancient greece: the role of color in ancient greek art and architecture (700-31 b.c.). thessaloniki: aristotle university of thessaloniki. 7 color culture and science journalvol. 13 (1) doi: 10.23738/ccsj.130101 color and/is narration. the narrative role of color in wes anderson’s filmic images greta attademo 1 1 department of architecture, university of naples federico ii, naples, italy. greta.attademo@unina.it corresponding author: greta attademo (greta.attademo@unina.it) abstract american director wes anderson’s films are an interesting case study on the use of representation and visual language as elements capable of implementing the narrative underlying the film plot. his films, in fact, are constructed according to a logic similar to that of architectural representations. the combination of geometries, perspectives, textures and colors generates a code of signs capable of mediating between the intelligible and the sensitive, between the idea and the image. in particular, chromatic aesthetics constitutes a carefully curated component in the image sequences. the balanced and perfect color compositions, however much they may seem a decorative whim, represent a clever narrative device that, designed according to logical patterns, is able to embody symbolic and communicative values. this research, therefore, aims to investigate the language of color in anderson's films, with the aim of analyzing its narrative potential. the color is investigated both as a narrative content of the filmic atmosphere and as a narrative container of emotions and symbols. the double register of analysis used for anderson's films can become a trace of a general methodology of analysis, applicable not only to the works of other directors, but also to other forms of visual narration. keywords wes anderson, color palette, films, chromatic perception, narrative color, movies sequences received 21/01/2021; revised 28/03/2021; accepted 31/03/2021 color and/is narration. the narrative role of color in wes anderson’s filmic images 8 color culture and science journalvol. 13 (1) doi: 10.23738/ccsj.130101 1. introduction the visual representation constitutes a communicative tool that accompanies the history of man since his birth, as clearly demonstrated by the examples of wall painting found in the lascaux caves, dating back to the paleolithic period. the language of images, in fact, for its characteristics of conciseness, immediacy and universality, allows the observer to understand the underlying messages only through the use of sight, the sense he has most developed and experienced. as scott mccloud also argues, the visual code has the ability to be understood by a generic individual without he has developed a specific formal education to interpret it, unlike what happens with the writing. the latter, in order to be understood, requires him to use a special vocabulary in order to decode the symbols of its language (mccloud, 1994). the role of visual narratives already embedded in the same root "idein/to see" of the words "eidos/idea" and "eidolon/image" is a topic of great interest, especially in today's society, where the concept of information culture is parallel to that of visual culture (manovich, 2005). in recent years, in fact, visual media have experimented and investigated the narrative potential of images, whether they are static (painting and photography) or dynamic (video games and cinema). in the latter, in particular, the relationship between representation and narration is fundamental. the visual experience, in fact, is the dominant means of communication, so much so that it can acquire perfect narrative autonomy, as demonstrated by the first silent films. the story is an essential element, because each film sequence has its corresponding one that, mounted to the others, goes to configure the overall narrative. among the formal elements of visual language used in cinema, color is certainly one of the most effective tools, because, in addition to contributing to the determination of tones, atmospheres and rhythms of the narrative, it is endowed with great psychological power, able to convey messages by leveraging emotional and perceptual factors of the audience. with the aim of analyzing the narrative potential of color in cinema, the research focuses on the films of american director wes anderson. in his films, in fact, the color is used both as content and as a narrative container, responding to the kandiskyan idea according to which “color is the keyboard, the eyes are the hammers, the soul is the piano with its many chords” (kandinsky, 1996). 2. visual storytelling in wes anderson's cinema. a methodology of investigation wes anderson is an american director, screenwriter and film producer, who became famous for the great attention paid, in each of his films, to the definition of a precise and structured "aesthetic guideline" (vaughn vreeland, 2015), able to make itself immediately recognizable to the viewer. the logic through which anderson constructs filmic images is similar to that of architectural representations. the combination of geometries and perspectives, as well as the care and attention in the composition of patterns and colors, in fact, generate a code of signs capable of mediating between the intelligible world and the sensitive one, transforming every idea into an image and every image into a story. although the scenes are in motion, the compositional characteristics adopted by the director instill in the viewer the feeling of being in front of a painting. the camera, in fact, placed perfectly central and perpendicular to the scene, seems to move slowly along an imaginary grid of vertical and horizontal lines, thus building the story through prolonged sequence plans. when it is necessary to take a break in the montage, the camera, while changing its position, maintains its perpendicularity to the frame, giving the observer an ideal, symmetrical and perfect point of view. in particular, anderson's style is distinguished by the role given to chromatic composition which, carefully crafted, confers an aesthetic logic to the visual compositions of each film (seitz, 2013). the balanced and perfect color compositions, however much they may seem a decorative whim, represent a clever narrative device. the attention to the lights, to the chromatic combinations and to the calibration of the tones becomes for the director an element of support in the determination of the overall narrative atmosphere. the colors, moreover, are used in their emotional and symbolic component, with the aim of stimulating the mind of the audience, creating specific impulses and feelings necessary for the interpretation of the contents of the story. wassily kandinsky, theorizing about color in "concerning the spiritual in art", states that it acts simultaneously on two levels: the first is physical, based on the concrete visual sensation obtained from the observation of the chromatic phenomenon; the second is psychic, in which color, once processed by the brain, defines its role on the allegorical and perceptual level (kandinsky,1996). starting from these considerations, it is interesting to investigate the color of anderson's films through this double register of analysis: on the one hand, it will be investigated as a tool to support the narrative in which it is inserted; on the other hand, we will focus on its ability to trigger a series of emotional and symbolic relationships in the viewer. 3. color and narrative. the construction of the filmic atmosphere in the films of wes anderson, color is one of the main elements in the implementation of the narrative. as set color and/is narration. the narrative role of color in wes anderson’s filmic images 9 color culture and science journalvol. 13 (1) doi: 10.23738/ccsj.130101 designer adam stockhausen explains, color is first studied to determine a general atmosphere, common to all his films, and then modeled on the individual narrative sequences, thus defining a specific palette for each of them (grobar, 2015) (vaughn vreeland, 2015). anderson's filmic narrative is always composed of particular, undefined and enigmatic plots. the characters do not specifically belong to the categories of protagonists/antagonists, because both dark and delicate aspects of them are shown. the film genre is never well defined, having comedies with nostalgic tones and dramas with bittersweet endings. this condition of indeterminacy is also communicated through color: the chromatic choices, the brightness and the calibration of shades, in fact, contribute to the construction of a stylized aesthetic (zettl, 2011), aimed to communicate a narrative world explicitly fictitious and deliberately artificial (lee, 2016). at the beginning, in fact, the color palette is reduced to a few essential colors, generally pastel tints, able to introduce the unrealistic and fairy-tale atmosphere. to the succession of scenes, then, corresponds a chromatic transformation increasingly synthetic: from pastel colors, soft and dusty, we pass to defined and saturated colors that, making each frame more artificial than the previous one, emphasize the story of a theatrical and surreal universe (bartolomei and ippolito, 2016). in "the grand budapest hotel", for example, the ethereal tones with grey dominants of the initial scenes are transformed, as the narrative continues, into strong and distinct oranges and browns, until the insertion, in the final scenes, of shades of blue and violet (fig.1). the sensation of a dreamlike and timeless world is also reinforced by the relationship between the chromatic choices of the filmic photography and those of the costumes and sets which, combining, generate retro atmospheres characterized simultaneously by nostalgic tenderness and jovial fun. one thinks of the yellow/blue patina that permeates skies, buildings and clothes in "moonrise kingdom", capable of recalling old family photographs, as well as the orange/brown lens of "the darjeeling limited", capable of creating oriental atmospheres inhabited by vintage characters. the synchronic composition of all the colors of the representation unifies the characters to their worlds, almost as if they could only live in that particular context. moreover, even when darker events occur, the colors are kept bright and brilliant, ensuring that the viewer always has in mind that the one observed is a representation of a fantasy (austerlitz, 2010). the perception of unreality is also communicated through the lighting: the light, always warm and soft, brings out the particular chromatic contrasts. the position of the light sources, often frontal to the scene, does not create strong shadows even in interiors, where the lights are diffused, determining a further flattening of the images. the color, therefore, serves to support the director's message to the audience: by explaining the artifice, in fact, anderson makes the viewer aware that what he is observing is not a faithful reproduction of reality, but a fictitious story that is located in a different world. fig. 1. the transformation of color in the narrative sequences of "the grand budapest hotel". although the general definition of chromatic features is similar in all of anderson's movies, the color is able to diversify each of his films. according to the director, in fact, every film needs a dominant color that, combined with a specific palette, allows to identify each story as different from the others (fig.2). it is due to this reason that only one or a few colors are used in an overwhelming manner, thus monopolizing the "projective foreground" of the viewer (yumibe, 2012). from the beige of "isle of dogs" to the yellow of "moonrise kingdom", from the blue of "the life aquatic" to the orange of "fantastic mr. fox", each film presents itself as a vivid memory reduced to a single color, emblematic of the microcosm it wants to narrate. the revelation of the process of emphasizing a single color is once again revealed by stockhausen. talking about pink, the predominant color in "the grand budapest hotel", he states that if only its tones had been used, its presence would have been cancelled in the eyes of the observer. he, becoming accustomed to the uniqueness of the chromatic stimulus, would stop seeing it (vaughn vreeland, 2015). for this reason, the addition of shades such as yellow and blue was necessary, so as to "cut" the dominant color, making it stand out more clearly (grobar, 2015). many studies show that the audience has little memory of color when reflecting on digital media (block, 2008). anderson, therefore, decides to increase color and/is narration. the narrative role of color in wes anderson’s filmic images 10 color culture and science journalvol. 13 (1) doi: 10.23738/ccsj.130101 the intensity and saturation of the main color in relation to those of secondary colors. in this way, the viewer can create an immediate association between color and film, thus transforming the chromatic signal into a factor of differentiation of the narrations (fig.3). fig. 2 color palettes in wes anderson's films fig. 3. dominant colors in wes anderson's films 4. color is narration. the chromatic associations between emotions and symbolism the studies on color perception, the neurosciences and the biology all agree that color can influence certain moods or can trigger specific psychological reactions in people (vaughn vreeland, 2015). these perceptions that color is capable of establishing are assimilated by the human mind according to the images formed over time in the collective memory and culture. according to yumibe, in fact, “through its sensual appeal, color can move the mind and emotions of a spectator. this understanding of the interconnection of the senses, intellect, and emotions is also, broadly construed, synesthetic in nature” (yumibe, 2012). prolonged exposure to a specific color, therefore, creates reactions in the viewer, capable of connecting to specific symbols and emotions (gegenfurtner and sharpe, 2000). it is possible to diversify the sensations produced by combining and mixing tones (itten, 1974). the psychological potential of color can be fundamental within film narratives, because the chromaticity of the images can itself be a story. in the works of wes anderson, in fact, color has become a real language through which to interpret themes and feelings of the characters and of the space they inhabit. saturation and color mixing create different environmental perceptions and psychological impacts (itten, 1974), while lighting and temperature establish relationships between characters and spatial contexts (vaughn vreeland, 2015). anderson balances the chromatic weight in different ways with the aim of generating a sense of environmental stability or instability (hurbis-cherrier, 2012). in this way, he determines two types of scenes, those that are harmonious and those that are alienating. the visual result is pleasant, communicating security, calm and peace to the viewer, when the colors used in a scene are similar or close in color wheel, and the colors of the costumes and accessories of the characters blend with those of the furniture and of the architecture. on the contrary, if complementary colors are used, the contrast between the tones, becoming jarring and disturbed, causes feelings of tension and discomfort (fig.4). the colors of the scene set in the elevator in "the grand budapest hotel", for example, show a clearly caricatural situation. the saturated red of the elevator seems to incorporate the characters inside it, suggesting a feeling of tension. this feeling can be seen on the face of madame d. who, not surprisingly, wears hat, gloves, dress and lipstick which are also of an intense red. the other characters are in contrast. the concierge and the lobby boys, in fact, wearing purple clothes, create a strident contrast with the red, emphasizing their feeling of discomfort and resignation towards the rich and impudent woman. on the contrary, the scene of the mendl's sweet boxes is substantially monochromatic. the pastel tones of pink and light blue make the contrast less accentuated, expressing a harmonious situation of intimacy and rediscovered love, in which even the chaos of the boxes is perceived as positive and delicate. color, moreover, becomes a symbol in anderson's films to introduce a certain theme or emotion to the audience (lee, 2016). the choice of specific colors and the variation of saturation scales of the tones, in fact, become emblematic in the construction of underlying meanings color and/is narration. the narrative role of color in wes anderson’s filmic images 11 color culture and science journalvol. 13 (1) doi: 10.23738/ccsj.130101 fig. 4. comparison between contrast and chromatic harmony in "the grand budapest hotel". (itten, 1974): the warm tones, from yellow to red-violet, symbolize humanity and life, contrasting with the cold tones, from purple to green, which are a metaphor of brutality and dehumanization. when richie decides to commit suicide in "the royal tenenbaums", the director does not show the action, but he uses color to narrate the event. the thematic opposition between death and life is in fact represented by the contrast between the soft blue that occupies the entire visual scene, and the bright red of the blood that flows in the arms of the main character. in contrast, the scene is colored with warm yellows, oranges and browns when richie himself discovers that his tormented love for margot is reciprocated (fig.5). the representation of color, moreover, often coincides with the emotional states of the characters, adding depth to their characterization, as happens with the pink of the young love between zero and agatha in "the grand budapest hotel" or with the orange of the rediscovered communion between the brothers francis, peter and jack in "the darjeeling limited". red, for example, seems to be a color associated with male characters' desire and issues with the father figure (vaughn vreeland, 2015) (fig.6). the young max, in "rushmore", wears a red hat in the moments in which he has the desire to have the affection of his father herman; chas, in "the royal tenenbaums", wears a red jumpsuit since his adolescence, when he develops a conflictual relationship with his father, and his children also wear it; the vintage red car in "the darjeeling limited", is the only object that connects the three protagonists to the father figure, with whom they wished to have a relationship, no longer possible due to his death. yellow, on the other hand, is often used by anderson as a color of optimism and union (fig.7). the sky is always tinged with yellow when the foxes are happy in "the fantastic mr.fox"; the yellow submarine is the only source of joy for the protagonist of "the life aquatic of steve zissou"; the boy scouts wear yellow neckerchiefs in "moonrise kingdom" when they start a collective exploration. fig. 5. warm tones and cool tones as symbolic and emotional expression in "the royal tenenbaums" 5. conclusions the analysis of the cinematographic images of wes anderson is an interesting starting point to understand how color is an integral part of filmic narration. the specific case of the films of the american director, capable of creating a symbiotic relationship between aesthetics and narrative, highlights the different communicative potential of color. hues, saturations and tones allow to make explicit the director's intentions and ideas, differentiating the tone, rhythm and plot of each story. the different relationships between the colors, able color and/is narration. the narrative role of color in wes anderson’s filmic images 12 color culture and science journalvol. 13 (1) doi: 10.23738/ccsj.130101 to generate contrasts, harmonies and different chromatic weights, stimulate instead the perceptions and feelings of the viewer in relation to the stories told. the color is investigated both as a narrative content of the filmic atmosphere and as a narrative container of emotions and symbols. the double register of analysis used for anderson's films can become a trace of a general methodology of analysis, applicable not only to the works of other directors, but also to other forms of visual narration. fig. 6. the color red as an expression of the conflictual relationship with the father figure. from top to bottom: "rushmore," "the royal tenenbaums”," the darjeeling limited" fig. 7. the color yellow as a metaphor for union and optimism. from top to bottom: “fantastic mr. fox”, “the life aquatic”, “moonrise kingdom” 6. conflict of interest declaration the author declares that nothing affected her objectivity or independence and original work. therefore, no conflict of interest exists. 7. funding source declaration this research did not receive any specific grant from funding agencies in the public, commercial, or not-forprofit sectors. color and/is narration. the narrative role of color in wes anderson’s filmic images 13 color culture and science journalvol. 13 (1) doi: 10.23738/ccsj.130101 8. short biography of the author greta attademo -• architect, ph.d.student at the university of naples, department of architecture (diarc). her fields of research are the relationships between the space and visual culture, and drawing in architecture and design. references austerlitz, s. (2010) another fine mess: a history of american film comedy.chicago, il: chicago review press. bartolomei, c. and ippolito, a. (2016) ‘il disegno come narrazione: grand budapest hotel’, in le ragioni del disegno – the reasons of drawing. atti del 38° convegno internazionale dei docenti della rappresentazione, pp. 1329-1336. block, b. (2008). the visual story: creating the visual structure of film, tv and digital media. abington, uk: taylor & francis group. gegenfurtner, k., and sharpe, l. (2000). color vision: from genes to perception. cambridge: cambridge university press. grobar, m. (2015). creating wes anderson’s wacky world is just another day at the office for ‘grand budapest’ production designer adam stockhausen, deadline online. available at: https://deadline.com/2015/02/grand-budapest-hotel-adam-stockhausenwes-anderson-oscar-nominated-production-design-1201371523/ (accessed: 20 february 2020) hubris-cherrier, m. (2012). voice and vision: a creative approach to narrative film and dv production. 6th ed. boston, ma: focal press. itten, j. (1974). the art of color: the subjective experience and objective rationale of color. hoboken, nj: john wiley & sons. kandisky, w (1996). lo spirituale nell’arte. milano: bompiani. lee, s. (2016). wes anderson’s ambivalent film style: the relation between mise-en-scène and emotion, new review of film and television studies, 14 (4): pp. 409-439. doi: 10.1080/17400309.2016.1172858 manovich, l. (2005). il linguaggio dei nuovi media. milano: edizioni olivares. mccloud, s. (1994). understanding comics. the invisible art. new york: harpercollins publisher. seitz, m. (2013). the wes anderson collection. new york, ny: abrams. vaughn vreeland, a. (2015). color theory and social structure in the films of wes anderson, elon journal of undergraduate research in communications, 6(2), pp. 35-44. yumibe, j. (2012). moving color. new brunswick, nj: rutgers university press. zettl, h. (2011). sight, sound, motion; applied media aesthetics. 6th ed. belmont, ca:wadsworth. 25 color culture and science journal vol. 11 (2) doi: 10.23738/ccsj.110203 primary colors as a source of possible misconceptions: an insight into teaching and learning about color berta martini1, monica tombolato1, rossella d’ugo1 [1] 1 department of humanistic studies, university of urbino ‘carlo bo’, italy. berta.martini@uniurb.it, monica.tombolato@uniurb.it, rossella.dugo@uniurb.it corresponding author: berta martini (berta.martini@uniurb.it) abstract in the field of science education, color can provide an interdisciplinary learning content, potentially suitable for overcoming disciplinary fragmentation and promoting in students a general attitude towards dealing with problems. however, because of its polysemic nature, it is very difficult to make students able to interpret, within the theoretical paradigm of modern science, a concept that they first learn to know through perceptual experience. as a pervasive phenomenon of our daily life, color vision gives rise, indeed, to a variety of naïve conceptions – similar to the pre-newtonian ones – that act as a filter to the new learning contents. in this context we identified, through a historical-epistemological analysis, the ancient contrast between simple and compound colors as a source of potential misconceptions to be investigated empirically. we hypothesized we could detect some misconceptions due to the lack of awareness of the different contexts – physics, physiology of vision, painters’ practice – in which the distinction between primary and secondary colors can be introduced, assuming different meanings in each one. we also believed that these misconceptions were relatively independent of the subjects’ level of education (children/teachers). then an empirical research was conducted by administering two different self-completed questionnaires to a non-probabilistic sampling of convenience made up of primary school teachers and fifth-grade pupils, respectively. the results of research on both teachers’ and children’s misconceptions seem to confirm what hypothesized. keywords misconceptions, primary colors, additive and subtractive color mixing, teaching and learning process, constructive theory of learning, newton’s prism received 31 march 2019; revised 11 july 2019; accepted 03 september 2019 primary colors as a source of possible misconceptions: an insight into teaching and learning about color 26 color culture and science journal vol. 11 (2) doi: 10.23738/ccsj.110203 1. background in the field of science education, color can provide an interdisciplinary learning content, potentially suitable for overcoming disciplinary fragmentation and promoting in students not a sterile accumulation of knowledge but a general attitude towards dealing with problems (morin 1999). however, because of its polysemic nature, it is difficult to make students able to interpret, within the theoretical paradigm of modern science, a concept that they first learn to know through perceptual experience (piana 2000; martinez-borreguero et al. 2013). as a pervasive phenomenon of our daily life, color vision gives rise to a variety of naïve conceptions, similar to the pre-newtonian ones, that are scientifically incorrect but of somewhat practical use. within the constructivist paradigm we speak, in this regard, of commonsense knowledge, that is of mainly implicit knowledge that acts as a filter to the new learning contents (mason 2006). howard gardner (2004) and stella vosniadou (2003), among others, highlight the negative influence that this implicit knowledge can have on students’ learning outcomes and on their capacity to intentionally apply what they have learned to new problem-situations. according to the two psychologists, these intuitive “theories”, which take shape in children’s minds to give meaning to the world phenomena, are one of the main causes of students’ elective failure in science. far from disappearing during the school years, these naïve conceptions, tacitly internalized through daily experience and communicative exchanges, often emerge, at an unthinking level, as a cognitive resistance to reasoning according to the logic of the discipline (martini 2018). this is a profound change from the traditional vision of learning. according to the constructivist learning theory, new knowledge is built upon what was previously learnt. in other words, the student is not a tabula rasa who passively receives the information transmitted by the teacher. on the contrary, she/he is an active knowledge builder who, before entering school, has already independently developed informal scientific concepts. these prior intuitive conceptions are highly resistant to change – as strike and posner suggest (1992) – because they are embedded within a broader conceptual ecology that consists of analogies, metaphors, methodological beliefs about “how science works”, knowledge from other domains, epistemological and ontological presuppositions, religious and metaphysical beliefs. a similar position is shared by vosniadou: on the basis of researches carried out in the field of elementary astronomy and mechanics, the psychologist hypothesizes that intuitive informal knowledge is articulated in mental models, specific theories and framework theories (vosniadou 2003). mental models – generated by the subject to solve problems, explain and/or predict phenomena of the natural world – are based on specific theories that consist of information – derived from observation or culturally transmitted – concerning the properties and behavior of physical objects. in turn, these specific theories are bound to framework theories, which are characterized by ontological and epistemological presuppositions about existing entities and the nature of knowledge. these presuppositions play an important role in constructing knowledge because they constitute the set of certainties on which everyday reasoning is based. if we extend these considerations to color vision, we can interpret the intuitive models generated by learners within two framework theories, which are compatible with some misconceptions discovered through empirical research (e.g., anderson and smith 1986; şahin et al. 2008; martinez-borreguero et al. 2013). the first framework theory is an ontology made up of assumptions derived from informal learning through our experiences and our social interactions. it describes various characteristics of the objects, including that of having their intrinsic color [3] (e.g. hawkins 1985, anderson and smith 1986; la rosa and meyer 1991; feher, e. and meyer, k. r. 1992; haagen, c. 2014). the second, instead, concerns the epistemological dimension of knowledge and assumes that things are as perceptually appear to be. these implicit presuppositions, developed in parallel with both everyday experience and ordinary language learning, act as a filter to scientific notions taught at school, which, in turn, can be vitiated by misconceptions due to the polysemy of the concept of color. in this context, we intend to analyze students’ learning difficulties by using the concept of epistemological obstacle. for this purpose, we propose a reassessment of the original concept, aimed at integrating bachelard’s and brousseau’s perspectives in light of an intentional theory of knowledge (tombolato 2018). the notion of epistemological obstacle is originally introduced by the french epistemologist (bachelard 2002) to identify the causes of stagnation and even of regression that lie at the very heart of the act of cognition. in this way, bachelard focuses attention on the psychological conditions in which scientific progress is made, concluding finally that the evolution of scientific thought requires to “know against” prior pre-scientific knowledge, which is highly resistant to change since rooted in everyday experience. brousseau (1983) later adapts the notion of epistemological obstacle to indicate the difficulties associated with the structural complexity of concepts in the field of mathematics education. he also undermines the key role that a historical analysis of the evolution of the discipline can play in highlighting these obstacles [4]. now, if we assume the subject-object intentional relation as a structural feature of knowledge, it is possible to make a synthesis between bachelard’s and brousseau’s primary colors as a source of possible misconceptions: an insight into teaching and learning about color 27 color culture and science journal vol. 11 (2) doi: 10.23738/ccsj.110203 perspectives, in order to increase the hermeneutic and heuristic power of the concept. within this framework the notion of epistemological obstacle can indeed be subjected to a double interpretation. on the one hand, it alludes to the idea that scientific contents can be conceptually understood as the objective correlates of peculiar epistemic practices [5] that appeared very “revolutionary” even to the scientists who first conceived them. on the other, it alludes to the misconceptions discovered through empirical research, which reveal the spontaneous tendency of subjects in learning to think in terms of reified concepts. because of commonsense habits and, sometimes, as a consequence of “naïve” teaching, we, indeed, are often inclined to ignore the processes that lead to the construction of such scientific contents and provide them with their meanings (tombolato 2018). at a methodological level, this implies two possibilities. we can employ heuristically naive physics conceptions to identify conceptual stumbling blocks within expert knowledge domain. otherwise, we can undertake a historical-epistemological analysis of the evolution of the discipline in order to infer potential misconceptions to be subjected to empirical testing. we selected this second option and decided to focus on the dispute between hooke and newton on the heterogeneous nature of white light as a source of possible misconceptions. newton proposes the analogy between the mixing of pigments and that of colored lights, defending his thesis against the objections – empirically founded – raised by his antagonist hooke. this is a clear evidence of how difficult is reformulating the artists’ practical knowledge of working with pigments within a scientific framework (giudice 2009) [6]. the difference between additive mixing of lights and subtractive mixture of pigments, clarified by hermann von helmholtz only in 1852, is therefore historically linked to the ancient contraposition between primary and secondary colors. this distinction is still a source of confusion for a lot of students because it can be introduced in different contexts – physics, physiology of vision, painters’ practice – assuming different meanings in each one. by taking into consideration shapiro’s article (1994), we will give a brief historical account of the genesis of this classification in order to clarify the three different perspectives (physics, physiology of the visual system, artists’ practice) from which it can be analyzed. in the “new theory about light and colors” newton affirms the existence of two sorts of colors: “the one original and simple, the other compounded of these” (newton 1672, p. 3082). this first general definition is subsequently modified to face the objections raised by hooke about the nature and number of primary colors, whose difference from the compound ones is now explained in terms of refrangibility: primary colors are those whose rays are all alike refrangible, while compound colors are those whose rays undergo a different refraction. experimentally this leads to a double possibility. let a beam of green light pass through a prism, it will undergo a refraction but not a dispersion, or it will be decomposed into rays of different colors (yellow and blue). therefore, newton argues, two rays of colored light that are perceptually identical may, however, differ in their physical composition. as shapiro points out, by primary (simple) newton means the “physically irreducible” colors, that is the differently refrangible monochromatic spectral colors in which white light is decomposed by a prism (shapiro 1994, p. 618). as a consequence of newton’s definition, there is an infinite number of primary colors due to the continuity of the visible spectrum. this statement sounds odd to hooke, who, on the contrary, referring to the arts tradition of pigment mixing, defines as primary the basic colors from which all the others can be obtained by composition. the gap between the two standpoints is partially due to the polysemy of the term “color” which can be used with very different meanings. strictly speaking, we should employ the locution “chromatic pigments” to refer to the colored substances used in painting, which clearly differ from the “visual color” that is the color perceived by the eye when it is stimulated by the various wavelengths reflected by such pigments. pigments work, indeed, by selectively absorbing some wavelengths from the white light, while reflecting others which evoke in human eye the corresponding colors. (de grandis 2000, p. 17). although newton and hooke disagree on the number and nature of primaries, both make no distinction between mixing pigments and mixing lights. this assumption, almost universally accepted, will be questioned by helmholtz only two centuries later, when he finds out the different rules applying to subtractive (pigments) and additive (lights) color-mixing processes. thus, his discovery let us move on to a third possible way to define primary colors. according to young-helmholtz's trichromatic theory, the primary colors of the spectrum are the triad of monochromatic radiations red, green, blue (rgb), which, additively combined (alternately and in different proportions), produce the entire range of colors and, as a limit case, a white light. in this sense, therefore, when referring to the primary colors of the spectrum we are concerned not with physical properties of light waves, but with the perceptual effects they produce on the visual system (de grandis 2000, p. 75). based on what outlined so far, we will try to unravel the ambiguity that lurks in the ancient distinction between simple and compound colors, by making explicit the different meanings underlying such a classification. our hypothesis, indeed, is that these different meanings can be correlated with potential misconceptions to be investigated empirically. primary colors as a source of possible misconceptions: an insight into teaching and learning about color 28 color culture and science journal vol. 11 (2) doi: 10.23738/ccsj.110203 in newton’s definition of primary colors is outlined the distinction between monochromatic spectral colors (simple), characterized by a particular wavelength (between 380 nm and 780 nm), and colors obtained by mixing lights (compound). although, sometimes, colors belonging to the second group may appear perceptually identical to the pure spectral colors of the first group, they differ from a strictly physical standpoint, however. in other words, there is no one-to-one correspondence between wavelengths and perceived colors: an object may appear yellow, for example, because it reflects light of wavelengths around 580 nm, while absorbing all the others, or because it reflects both red and green light, whose combination yields the same chromatic sensationwith different lightness perception. therefore, the same color sensation can be produced by entirely different physical stimuli. moving from physics to physiology of the visual system in our framework we just introduced the basic concepts of the theory of additive light colors mixing from primaries red, green and blue (rgb) and subtractive subtractive color mixing that predicts the spectral power distribution of light after it passes through successive layers of partially absorbing media from primary colors cyan, magenta and yellow (cmy). identified as the set of subtractive primary colors by a commission of international experts, the pigment colors cyan, magenta and yellow act as filters to white light in order to produce the additive triad (rgb). superimposing magenta and yellow filters we get red light, cyan and yellow filters we get green light, magenta and cyan filters we get blue light. finally, black results from the superposition of the three subtractive colors respectively (de grandis 2000, p. 18). in summary, in the first case a physical definition of “simple” colors in terms of monochromatic rays of light (that is rays of a determinate wavelength) is provided. in the second case, with reference to the physiology of the visual system, the primary colors are identified with the rgb additive color model in which red, green and blue light are added together in various ways to produce all the other colors. finally, the subtractive primaries are those basic colors (de grandis 2000, p. 17 note 1) used in painting and more generally in printing, photography and cinematography (cmy) which, by filtering white light as described above, allow the three additive colors rgb to be obtained as the result of light subtraction by absorption. 2. research hypothesis in this context, we carried out an empirical research aimed at detecting possible misconceptions about color held by primary school pupils and teachers. the hypothesis of the research is that some misconceptions are linked to the lack of explicit distinction between physics, physiology of the visual system and painters’ practice standpoint, respectively. we also believe that these misconceptions are relatively independent of the subjects’ level of education (children/teachers). in particular, we expected to detect the following children’s misconceptions: (1) the belief that color is an intrinsic property of objects and the confusion between light colors and pigment colors (qc1, qc2). these misconceptions are well known in scientific literature (see note 3) (e.g. hawkins 1985, anderson and smith 1986; la rosa and meyer 1991; feher, e. and meyer, k. r. 1992; haagen, c. 2014); (2) difficulty in distinguishing between mixing of pigments and mixing of lights (qc3, qc4, qc5); (3) the knowledge of primary colors limited to the painters’ practice standpoint taught in arts education (qc4); (4) the merely superficial knowledge of the physical interpretation of color (qc6). as for teachers’ misconceptions, we expected to detect: (1) poor knowledge of the scientific interpretation of the color vision phenomenon (qt1, qt2); (2) knowledge of primary colors only as pigment colors out of which all the others can be made (qt3, qt4); (3) inability to distinguish between “almost pure colors” (characterized by a dominant wavelenght and a narrow band) and colors produced by the addition of lights (qt5, qt6, qt8); (4) confusion between the mixture of pigments and that of colored lights (i.e. between additive and subtractive synthesis). in particular, our hypothesis is that the colored light is mixed with the “color of the object”, as expected from the pigment mixing model. this implies teachers hold the (more or less implicit) belief that color is a quality of objects independent of both the type of light source that illuminates the object and the characteristics of human vision (see note 3) (qt7, qt9). 3. methodology and tools the research was conducted by administering two different self-completed questionnaires (corbetta 2003, p. 179) allowing subjects to answer questions independently, without the need for an interviewer to be present. the two questionnaires were addressed to primary school teachers and to fifth-grade pupils, respectively, according to a nonprobabilistic sampling of convenience. the sample consisted of: primary colors as a source of possible misconceptions: an insight into teaching and learning about color 29 color culture and science journal vol. 11 (2) doi: 10.23738/ccsj.110203 – 30 primary school teachers from the province of pesaro-urbino. – 92 fifth-grade pupils. in particular, 18 children attending the school complex in cattolica (rn), 11 attending the school complex binotti in pergola (pu), 22 attending the school complex olivieri in pesaro (pu), 21 attending the school complex pascoli in urbino (pu) and 20 attending the school complex villa san martino (pu). data from the two groups were collected as follows: teachers answered the questionnaire under the guidance of an internship tutor from “education sciences for nursery and primary school” at urbino university, who had previously been “trained” by the authors of this article. the children were informed in advance about the purpose of the investigation and assisted in filling in the questionnaire by their own teachers, who were given precise instructions to carry out a data collection as errorfree as possible. 4. children's misconceptions research results below we provide the children’s answers to the questionnaire (qc), organized according to response types gained from the reading of the data. qc1. what is color for you? color is linked to emotions 32 35% an object property/a tool that colors things 13 14% color is a light/colored light 11 12% paint/colored spot/colored substance 11 12% tautological answers: e.g., “color is a colored form” 5 5% answers that identify a function of the color: “the color is needed to ...” 3 3% don’t know 3 3% not relevant 2 2% other 12 13% qc2. why do we see objects of different colors? because everything has its color 20 22% by means of light/sun 16 17% because of emotional reasons 14 15% because they are painted 13 14% because our eyes can do it 12 13% in order to distinguish them 8 9% don’t know 5 6% other 4 5% the first two questions were aimed at detecting children’s naive conceptions about color. first, a marked variety of response types (especially regarding the first question) may easily be noted. among the answers the most common (35% for the first question and 14% for the second question) were those that interpret color as a source of feelings and emotions: “color is a source of joy”. the idea of color as an intrinsic quality/property of objects is widespread as well (14% for the first question and 22% for the second): “because everything has its color”; “because god wanted so”. this naïve idea is implied, more or less implicitly, also by the answers (about 14% of the total) according to which we see objects of different colors because they have been painted/colored. the concept of color as light occurs in 12% of responses to the first question and in 17% of responses to the second question. the answers, however, highlight naïve conceptions: “color is a light that colors things”; “color is a colored light”; “we see objects of different colors because the light ‘touches’ an object and gives it color”. questions qc3, qc4 and qc5 have been proposed to detect children’s misconceptions related to the analogy between light mixing and pigment mixing. qc3. is it possible to get a black light by mixing colored lights? yes 55 60% no 35 38% don’t know 1 don’t answer 1 qc4. what are primary colors? what primary colors do you know? they are those colors that allow to produce all the others/those which cannot be derived from any others 27 29% don’t know 17 18% they provide only color occurrences 14 15% they are the most used colors 7 8% they are the lightest colors 6 7% they are the ones that come first 5 5% they are the “prime” colors 2 2% other 14 15% among children who claim to know primary colors: they mention the triad red-green-blue 2 2%c they mention the triad red-yellow-blue 19 21% they provide incorrect examples of colors 50 54% qc5. let’s imagine putting a very big traffic light in the classroom and turning off the light. when the red light comes on, what color does the blue chair appear to be? violet 38 41% red/red and blue 8 9% black 7 8% brown/orange 7 8% green 6 7% yellow 4 4% blue 3 3% don’t know 6 7% don’t answer 4 4% other 9 10% primary colors as a source of possible misconceptions: an insight into teaching and learning about color 30 color culture and science journal vol. 11 (2) doi: 10.23738/ccsj.110203 regarding question qc4, children respond adequately in 29% of cases. the reason may lie in the fact that the answer corresponds to a traditional teaching content. as we will see later, this datum is confirmed by the answers provided by the teachers. however, this does not mean that the underlying conception is fully correct. as a matter of fact, even when children provide a plausible explanation of what primary colors are, they identify incorrect colors. another interesting result concerns the triads mentioned: red-green-blue (2%) and red-yellow-blue (21%). they identified two distinct categories of primaries, the first referring to the additive synthesis of lights, while the second to the subtractive mixture of pigments. however, the occurrence of these two triads in children's responses is not justified on the basis of this distinction. the fifth question (qc5) was intended to ascertain the confusion between the mixture of pigments and that of colored lights. evidence in favor of this hypothesis comes from 41% of the responses, where children state that in the described circumstances they chair would appear violet, exactly as would result by overlapping the red of the light and the blue color of the chair. further evidence is provided by the high percentage of affirmative responses (60%) to qc3, showing that the pigment mixture model is used even when lights rather than pigments are mixed. the responses to the last question (qc6) are displayed in table below. the answers show that 10 children refer to the scientific phenomenon of light decomposition: 4 explicitly allude to the visible spectrum and 6 allude to the phenomenon of decomposition. however, even in this case, their responses reveal a merely superficial knowledge. “inside the prism, the white light reflects to the glass and so gives rise to the visible spectrum”; “passing through the prism, white light splits into the visible spectrum”. some children (9) answer that they have already heard of newton’s prism, which is, indeed, a traditional learning content taught at school. qc6. do you know newton's prism? they say they don't know newton's prism 24 26% they claim to know newton's prism 9 10% don’t answer 59 64% can you tell what happens to white light when it passes through the prism? the light becomes colored / turns into a rainbow 33 36% i don’t know 16 17% light splits into colors 6 7% the visible spectrum is formed 4 4% they describe different phenomena 21 23% other 12 13% our supposing that children fail to show a meaningful understanding of the scientific phenomenon is supported by the fact that if we compare these answers with those given by the same children to the previous questions, internal inconsistencies emerge. for example, with reference to the first of the responses cited above – “inside the prism, the white light reflects to the glass and so gives rise to the visible spectrum” –, the same pupil to the question “what is color” (qc1) answers: “an ink that paints things”. 5. teachers's misconceptions research results we provide the results of the teachers’ questionnaire (qt) without specifying the percentage data because of the narrowness of the sample. as regards the first question (qt1) – “why do we see objects of different colors?” (a question corresponding to qc2 of the children’s questionnaire) – most teachers (21 out of 30) make a general reference to light absorption and reflection phenomena. deep knowledge gaps emerge from 7 answers. in just 2 cases, teachers offer more precise responses including each of the three elements involved in color vision (light source, human eye, objects absorbing and reflecting wavelengths of light). for example: “because our eye has the ability to see the colors of light reflected by various objects”. if asked about the nature of black and white – “how can black and white be defined with reference to what is represented by figure 1?” (qt2) – two teachers provide correct definitions: in one case, white = light, black = absence of light; in the other, white is the mixture of all colors, black is the absence of light and thus of color. many recognize black and white as non-colors but providing incorrect justifications or not providing any. in 7 other cases the teachers refer to white and black as colors of objects. concerning questions qt3 and qt4 aimed at investigating naïve ideas about primary colors (see figures 2 and 3), most answers show they are mainly defined as the colors from which all the others derive. fig. 1. prismatic decomposition of light there is no clear awareness about the difference between light colors and pigment colors, however. except for two cases, teachers, indeed, do not distinguish between additive and subtractive primaries. moreover, similarly to what emerges from children’s responses, the primary colors as a source of possible misconceptions: an insight into teaching and learning about color 31 color culture and science journal vol. 11 (2) doi: 10.23738/ccsj.110203 predominantly cited primaries are the traditional painters’ ones (red, yellow and blue), as a further proof of the dominance of the pigment mixing model. the question qt5 asks if “two perceptually identical colors can be different from a physical standpoint”. teachers respond “yes” in 23 cases out of 30. however, if we compare these answers with those given to questions qt6 and qt8, it is hard to suppose they really understand the difference. when asked the reason why a lemon appears yellow (qt6), only 2 teachers are aware of the double possibility that the lemon reflects the wavelength corresponding to yellow light or the wavelengths corresponding to red and green lights (proving to interpret yellow as a result of the additive synthesis of these two light colors). moreover, considering question qt8 – “is there a difference from a physical standpoint between the yellow color in figure 1 and the yellow color in figure 2? if yes why?” – which actually provides an exemplification of question qt5, only 9 teachers answer yes and, among these, only 2 partially justify their choice. fig. 2. additive color mixing fig. 3. subtractive color mixing regarding question qt7 – “if an object illuminated by sunlight appear blue, what color will it appear to be if illuminated by a light source emitting only red-light beams?” –, 11 teachers answer the object will appear violet. among the others, 6 teachers opt for black, 4 for blue, 2 for green, 1 for brown and 1 for pink, respectively. finally, 3 teachers admit not to knowing the answer and 1 does not respond. it is noted that also in this case, as in the case of question qc5 addressed to children, most responses converge on the same choice that is violet. this confirms that the dominance of the pigment mixing model is relatively independent of the level of schooling attained. our hypothesis is further corroborated by the answers to the last question qt9 – “how will appear a magenta colored object that absorbs the wavelengths corresponding to the green, if illuminated with monochromatic radiation, i.e., light of a single color such as red, blue or green respectively? and finally, how will it appear in sunlight?” –, most of which are null (they do not know or do not answer) or irrelevant. in 4 cases, teachers’ predictions highlight the pigment mixture model underlying their reasoning. for example: “(...) if the magenta object were illuminated by green light, we should see it black because magenta is made up of red and blue, so, adding green light, we would obtain the triad that produces the black color (...)”. 6. discussion and conclusive remarks as regards the hypotheses formulated in section 2, the following conclusions can be advanced for the research carried out on children and teachers respectively. (1) the conception of color as an intrinsic property of objects emerges both explicitly from some responses and implicitly, as a presupposition underlying other misconceptions. (2) the confusion between light and pigment colors is highlighted by the high response rate to question qc3. this tendency is confirmed by the evident lack of distinction between additive and subtractive primaries as shown in qc4, as well as by the dominance of the pigment mixing model in qc5, where reference is made to the overlap between the red light and the blue color of the chair (conceived as an intrinsic quality of the object). (3) unlike what was hypothesized, not all children in our sample know primary colors. some of them provide interpretations partially relevant, while others make references to other fields of experience. those who show to have some, albeit superficial, knowledge of primary colors confirm that it is circumscribed to the painters’ triad (red, yellow, blue), probably acquired during school arts activities. (4) a small minority of children refers to the spectral decomposition of light passing through a prism. however, we assume that theirs is a merely superficial knowledge due to the lack of consistency primary colors as a source of possible misconceptions: an insight into teaching and learning about color 32 color culture and science journal vol. 11 (2) doi: 10.23738/ccsj.110203 with the answers previously given, which point out the persistence of the misconceptions highlighted above. as regards the hypotheses formulated about the teachers, the following conclusions are advanced. (1) the scientific mastery of the color vision process is somewhat partial. teachers, indeed, refer to the three basic elements of color vision (light source, human eye, objects absorbing and reflecting wavelengths of light) in only two cases. this is also confirmed by the limited relevance of the responses to the second question, i.e. about the definition of white and black with reference to the prismatic decomposition of light. (2) the knowledge of primary colors is almost exclusively limited to their interpretation as the basic pigment colors whose mixture produces all the others. as a matter of fact, teachers mainly mention the painters’ triad red-yellow-blue, showing no awareness of the difference between additive and subtractive primaries. (3) teachers confuse physical and physiological aspects of color vision since they do not distinguish between spectral monochromatic colors (colors with single wavelengths) and non-spectral colors that can be obtained as a result by adding lights of different wavelengths. although in some cases non-spectral colors are perceptually identical to monochromatic colors, they are different from a physical standpoint, however. (4) the hypothesis of the misleading analogy between the mixing of lights and the mixing of pigments (i.e., between additive and subtractive synthesis) is confirmed. similar to what was observed with children, many teachers tend to mix the color of the light illuminating the object with the color of the object considered as its intrinsic property. from what is outlined above, the following conclusion can be drawn: both teachers and students show misconceptions and naïve ideas about color vision due to the lack of explicit distinction between physics, physiology of the visual system and painters’ practice standpoint, respectively. more, this confirms that the misconceptions highlighted in this paper are relatively independent of people’s level of education; on the other hand, it points out the necessity to make these three different perspectives explicit in teaching and learning process, in order to foster a meaningful knowledge about color. 7. conflict of interest declaration the authors declare that nothing affected their objectivity or independence and original work. therefore, no conflict of interest exists. 8. funding source declaration this research did not receive any specific grant from founding agencies in the public or not-for profit sectors. 9. short biography of the authors berta martini full professor at university of urbino – dept. of humanistic studies – where she teaches general didactic and pedagogy of knowledge. she is co-director of the online scientific journal pedagogia più didattica, and she is a member of the scientific boards of peer review journals and publishing series. her main fields of research are the processes of transmission of knowledge and in curriculum studies. rossella d’ugo researcher in experimental pedagogy at university of urbino – dept. of humanistic studies – where she teaches docimology and experimental pedagogy. her research is mainly oriented to the study of evaluation and self-evaluation tools and methods to ensure the quality of educational contexts as well as of the teaching practices of educators and teachers. monica tombolato phd in epistemology and in education (university of urbino). she is currently a postdoctoral fellow and a contract professor for the pedagogy of knowledge lab and physics education lab at university of urbino – department of humanistic studies. she is the author of essays and articles concerning the philosophy and pedagogy of knowledge. notes [1] the paper was written by the authors jointly. specifically, b. martini wrote sections 4 and 6; m. tombolato wrote sections 1 and 5; r. d’ugo wrote sections 2 and 3. [2] in this context, assuming intentionality as a structural feature of knowledge means highlighting the “perspectival character” of scientific knowledge. as suggests the philosopher of science evandro agazzi (2014, p. 83), different disciplines investigate ‘things’ from different perspectives. the same ‘thing’ can thus become the object of a variety of sciences when considered from different standpoints. [3] from a didactic standpoint, this means that the color of an object is conceived as being independent of both the type of light source that illuminates the object and the characteristics of human vision. making the example of a person looking at a colored object in white light, anderson and smith (1986) highlight two different interpretations capable of explaining the observed phenomenon: primary colors as a source of possible misconceptions: an insight into teaching and learning about color 33 color culture and science journal vol. 11 (2) doi: 10.23738/ccsj.110203 “1. a scientific interpretation: white light is a mixture of colors of light. objects absorb some of those colors of light and reflect others, and people see the colors of the reflected light. 2. a naive interpretation: white light is clear or colorless. it brightens objects and in so doing reveals their colors, which are innate properties of the objects themselves. people's eyes see the colors of the objects”. as haagen (2014) points out: “one prerequisite for understanding optics, including color phenomena, on a basic level is the idea that objects which do not produce light themselves are able to absorb and reemit light. only when light (re)emitted by an object enters the eye of an observer, he or she can perceive the object. this sender-receiver mechanism also determines the kind of color we see, as the color depends on the kind of light we receive. consequently, without this basic concept of a sender selective (re)emission receiver model, it seems to be difficult to develop scientifically adequate ideas concerning color and colored objects”. [4] on the distinction between ‘obstacle’ and ‘mistake’ from an educational standpoint, see martini 2000, pp. 89-102. [5] consider, for example, galileo's approach to science based on the use of idealized models and thought experiments in order to interpret natural world phenomena. (mcmullin 1985). both idealized models and thought experiments are used in teaching about color and color vision, at least on a basic level. [6] numerous experiments showed that if two primary color lights (for example, red and green) are combined, new colors are obtained. on the contrary, by mixing the two corresponding pigment colors only dirty grays are obtained (de grandis 2000, p. 17). references agazzi, e. (2014) scientific objectivity and its contexts. heidelberg/new york/dordrecht/london: springer. anderson, c. w. and smith, e. l. (1986) ‘children's conceptions of light and color: understanding the role of unseen rays’. michigan: the institute for research on teaching. available at: https://eric.ed.gov/?id=ed270318. (accessed: 27 march 2019). bachelard, g. (2002) the formation of the scientific mind. manchester: clinamen. brousseau, g. (1983) ‘les obstacles épistémologiques et les problèmes en mathematiques’, recherches en didactique des mathématiques, 4(3), pp. 165-198. corbetta, p. (2003) la ricerca sociale: metodologia e tecniche. le tecniche quantitative. bologna: il mulino, vol. ii. de grandis, l. (2000) teoria e uso del colore. milano: mondadori. feher, e. and meyer, k. r. (1992) ‘children's conceptions of color’, journal of research in science teaching, 29(5), pp. 505-520. gardner, h. (2004) the unschooled mind: how children think and how schools should teach. new york: basic books. giudice, f. (2009) lo spettro di newton. roma: donzelli. haagen, c. 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(2008) ‘students' understanding of light concepts primary school: a cross-age study’, asia-pacific forum on science learning and teaching, 9(1), pp. 1-19. shapiro, a. e. (1994) ‘artists’ colors and newton’s colors’, isis, 85(4), pp. 600-630. strike, k. a. and posner, g. j. (1992) ‘a revisionist theory of conceptual change’, in duschl, r. and hamilton, r. (eds) philosophy of science, cognitive psychology, and educational theory and practice. albany, ny: suny press, pp. 147-176. tombolato, m. (2018) ‘la dialettica generale/specifico alla luce del costrutto didattico di ostacolo epistemologico’, formazione & insegnamento. rivista internazionale di scienze dell’educazione e della formazione, 16(2), supplemento, pp. 205-214. vosniadou, s. (2003) ‘exploring the relationships between conceptual change and intentional learning’, in sinatra, g. m. and pintrich, p. r. (eds) intentional conceptual change. london: lea, pp. 377-406. 31 color culture and science journal vol. 12 (2) doi: 10.23738/ccsj.120204 francesco algarotti explains newton’s prism experiment to ladies paola magnaghi-delfino1, giampiero mele2, tullia norando1 1 department of mathematics, politecnico di milano, milan, italy. paola.magnaghi@polimi.it, tullia.norando@polimi.it 2 università degli studi ecampus, novedrate (co), italy. giampiero.mele@uniecampus.it corresponding author: paola magnaghi-delfino (paola.magnaghi@polimi.it) abstract in the 18th century, a “new science” flowed in europe. one of the primary elements of enlightenment was the rise of the public sphere excluding women and lower classes. les philosophes introduced the public to many scientific theories, in particular newtonianism by voltaire and émilie du châtelet. some works are more formal, but the popular works were written in a discursive style. articles on scientific topics appeared in popular women’s magazines and books designed to introduce women to scientific disciplines. noted examples of this popular new genre include francesco algarotti’s newtonianism for ladies or dialogues on light and colours. this book was an 18th century best seller and was one of the main channels through which newtonian ideas reached the public in continental europe. the text explained the principles of newton's opticks while avoiding much of the mathematical rigor of the work in favour of a more "agreeable" text. algarotti presented newton as a follower of the galilean tradition and the first modern philosopher. the description of some of newton’s experiments on the nature of light and colours in the form of a gentle dialogue has great educational value, because it does not demand any geometrical or algebraic knowledge. in this article, the authors want to underline the importance of algarotti's book for the dissemination of newton's ideas that until then had been shared only by scholars. algarotti’s book today is testimony to women’s interest in science during 18th century. keywords optics, colour, enlightenment, algarotti received 18/10/2019; revised 10/01/2020; accepted 12/02/2020 francesco algarotti explains newton’s prism experiment to ladies 32 color culture and science journal vol. 12 (2) doi: 10.23738/ccsj.120204 1. introduction in the 18th century, enlightenment’s principles inspired a new genre of painting, music and the “new science” flowed in europe. one of the primary elements of the culture of enlightenment was the rise of the public sphere. the word "public" implies the highest level of inclusivity – the public sphere should be open to all. however, this sphere was only public to relative degrees. additionally, most institutions of the public sphere excluded both women and lower classes. an important development was the popularization of science among an increasingly literate population. les philosophes (philosophers) introduced the public to many scientific theories, most notably through the encyclopédie and the popularization of newtonianism by voltaire and émilie du châtelet. some works were more formal and included explanations of scientific theories for individuals lacking the educational background to comprehend the original scientific text. the popular works were written in a discursive style, which was laid out much more clearly for the reader than the complicated articles or treatises. articles on scientific topics appeared in popular women’s magazines and books designed to introduce women to scientific disciplines. noted examples of this popular new genre include francesco algarotti’s newtonianism for ladies or dialogues on light and colours (1737). this book was an 18th century best seller and was one of the main channels through which newtonian ideas reached the public, not only women, in continental europe. the widespread use of the book was also due to the fact that algarotti was well introduced in the english and french as well as in the italian cultural circles. algarotti frequented the salon of elisabeth montagu where he met elizabeth carter who translated the dialogues. later, algarotti became a great friend of frederick the great. the book brings together both groups of women, the amateur and the learned scientists. algarotti illustrated the book with an engraving of émilie du châtelet and himself set in a bucolic scene. the text explained the principles of newton's opticks while avoiding much of the mathematical rigor of the work in favour of a more "agreeable" text. in the book, algarotti presented newton as a follower of the galilean tradition and the first modern philosopher. the distinguishing feature of the book is that he presents the theory about the nature of light and colours by means of newton’s experiments. he shares. with galileo and locke, the same idea about the scientific value of experience, in antithesis with the cartesian method. the description of some of newton’s experiments on the nature of light and colours in the form of a gentle dialogue has great educational value, because it does not demand any knowledge of geometry or algebra. from this point of view, the literary quotes are always totally justified and meaningful. algarotti writes the verses in the beginning “o, of the golden sevenfold light the myriad ardent, mixed and glorious colours,” in honour of laura bassi, professor of philosophy and physics at the university of bologna. this quote shows his attention to the experimental method and recalls the period in which algarotti himself studied physics at the university of bologna. in this article, the authors want to underline the importance of algarotti's book for the dissemination of newton's ideas that up to that time had been shared only by scholars. in the 18th century, as pointed out, the salons where literature and science conversations were held were also very important. the conversations were held also by women, despite not being able to attend schools, who had to know and talk about the latest discoveries. so, algarotti’s book explains newton's theory in a simpler and less formal way with rhetorical figures and literary verses. therefore, algarotti’s book is witness to women’s interest in science in 18th century. 2. importance of decomposition of white light in eighteenth century in 18th century there is a reassessment of the connections between practical techniques, philosophical ideas and the cultures in which they resided. the production of dyes, pigments and glazes were well established industries. colour was a subject of systematic experimental and theoretical investigations in the sciences. colour brought philosophical ideas close to everyday experience. in books and lectures directed at popular audiences, colour was used to illustrate connections between methods and theories, emphasizing the familiarity and practicality of colour making techniques. the characterization of chemistry in eighteenth century as under fledged in comparison to physics meant that mainly mathematics, mechanics, optics and dioptrics were present in discussions of colour practices. reference to newton, descartes, gassendi and even aristotle were obligatory in practical writing intended for publication. colour was part of a developing art or tangential to science. the expanded place of the sciences in public and private life explains the interest in learning the book of nature, that the sciences provided with exemplary systems, visible or invisible as the laws of motion or mathematics. there were many strategies for disseminating information. the transfer could be purely verbal, as in conversazioni or lectures, or by means of a combination of verbal and visual strategies (fig.1). colour was a topic with clear connection to science. it suggested visible and tangible opportunities to join theories and practice, providing a unitary focus for systematic conjecture and experiment. (lowengard, 2005). francesco algarotti explains newton’s prism experiment to ladies 33 color culture and science journal vol. 12 (2) doi: 10.23738/ccsj.120204 fig. 1. conversazioni or lectures 3. newton prism experiment between 1665 and 1666, isaac newton realized a series of experiments with the prism that radically transformed traditional ideas about the nature of light and colours. he made a small hole in the window of his perfectly darkened room. he caused a prism to intercept the ray of light that penetrated from the small opening, projecting the image onto a wall several meters away, on which he observed a non-circular, but elongated spectrum in which all the colours of the iris were revealed. newton also showed the reversibility of the experiment: by projecting the polychrome spectrum on a converging lens, the white light beam was in fact regenerated. from these experiments he deduced that the colours were not, as descartes had assumed from aristotle, accidental modifications of white light. the latter no longer appeared as an elementary but heterogeneous substance: the product, that is, of mixing different colours. newton correctly stated that the spectrum appeared elongated because the various colours have different indices of refraction. he derived from this discovery the idea of the reflecting telescope, capable of considerably attenuating the annoying effects of chromatic aberration. the results of this research were published by newton in the philosophical transactions of the royal society in 1672 and 1675. the newtonian theory of light and colour stirred lively debate. the comparison with the wave theory of light supported by huygens was particularly lively. experiment’s description (newton, 1704) place a prism (whose angle fbd is about 60°) in a dark room in which the sun passes only through a small round hole k and holding it near the hole k so that the rays being equally refracted in n and in h, project rstv colours on the opposite wall (fig. 2). the colours are refracted forming an oblong shape bounded in the sides r and s by straight lines. the amplitude rs is 2 1/3 inches, their length about 7 or 8 inches and the distance of the centres of red and blue (p and q) are about 3 inches. the distance of the rstv wall from the prism is 260 inches (about 6.70 meters).[1] in another experiment, newton took a prism on a face of which he placed a sheet of paper with different bands parallel to the edges of the prism and placed at a regular distance. passing through these cracks, the sunlight, collected on a screen near the prism, produced a coloured line at each slot. however, as soon as the screen moved away, white formed in the central part of the spectrum. if the screen was placed at an even greater distance, the whole spectrum reappeared. fig. 2 newton's experiment drawing (drawing by authors of this text) 4. francesco algarotti: a venetian polymath count francesco algarotti (1712–1764) was an eclectic scholar: philosopher, poet, essayist, art critic and art collector. he was a man of broad knowledge, an expert in newtonianism, architecture, music and a friend of most of the leading authors of his age. voltaire, jean-baptiste de boyer, pierre-louis de maupertuis, lord chesterfield, thomas gray, metastasio, benedict xiv and heinrich von francesco algarotti explains newton’s prism experiment to ladies 34 color culture and science journal vol. 12 (2) doi: 10.23738/ccsj.120204 brühl were among his correspondents. algarotti was born in venice as the son of a rich merchant. unlike his older brother bonomo, he did not step into the company, but decided to become an author. francesco studied natural sciences and mathematics in bologna under francesco maria zanotti and in 1728 he experimented with optics. at the age of twenty, he went to paris, where he became friendly with voltaire and émilie du châtelet. the first french introduction to newtonianism and the principia was eléments de la philosophie de newton, published by voltaire in 1738. émilie du châtelet's translation of the principia, published after her death in 1756, helped to spread newton's theories beyond scientific academies and the university. bernard de fontenelle's conversations on the plurality of worlds (1686) was the first significant work that expressed scientific theory and knowledge expressly for the laity, in vernacular and with the entertainment of readers in mind. the book was produced specifically for women with an interest in scientific writing and it inspired a variety of similar works and pushed algarotti to write his book about newton’s optics during his stay in cirey, guest of voltaire and du châtelet. when he was in london, he was made a fellow of the royal society and joined the friends’ circle of lady mary wortley montagu. among them there was elisabeth carter, the poet, linguist and polymath, who later translated his book. in 1737, algarotti left for italy and finished neutonianismo per le dame (newtonianism for ladies), dedicated to bernard le bovier de fontenelle, a work intended for the popularization of newtonian philosophy and addressed to women. algarotti wrote il newtonianesimo per le dame, ovvero dialoghi sopra la luce e i colori as a series of six dialogues. first dialogue: introduction; a general idea of physics, and an explanation of the most remarkable hypothesis concerning light and colours. second dialogue: that qualities, such as light, colours, and the like, are not really in bodies. metaphysical doubts concerning our sensations of them. explication of the general principles of optics. third dialogue: several particulars relating to vision, discoveries in optics, and a confutation of the cartesian system fourth dialogue: encomium on experimental philosophy, and an exposition of the newtonian system of optics fifth dialogue: exposition of the newtonian philosophy continued sixth dialogue: exposition of the newtonian universal principle of attractions and application of this principle to optics. (algarotti, 1737) 5. newtonianism for ladies algarotti began his book with the following sentence i am putting the last touches to my dialoghi, which have found grace in the eyes of the belle émilie and the savant voltaire. i try, when near them, to acquire those choice terms, that charming turn of speech with which i should like to embellish my work. algarotti illustrated the book with an engraving of émilie and himself set in a bucolic scene, which represented the cirey gardens with the château on the right. fig. 3. source linda hall library of science, engineering & technology the marquise was highly flattered at being placed at the head of the work to represent “wit, grace, imagination, and science.” the book was published with a title that did not refer to women, leading some to believe that the female branding of the book was a ploy to avoid censorship. algarotti had to make changes, certainly not improving the text, in the most famous editions following the first. the changes are both in the content and in the expressive form, in order to avoid a further condemnation, or the accusation of harmful work to morals of young people. he eliminated any reference to sensationalist gnoseology and praise of experimental philosophy, every positive judgement of ancient atomism, and every expression deemed excessively free and polemical. the "tone” of research, of direct investigation, the language so close to the daily use of the things, which we find in the first edition of the "dialogues", is less in the following ones. the civil tension and the true will of renewal, which is easy to detect in the first edition—emphasizes experimental philosophy as a methodology valid in every field, from natural research to political practice—which are lost in a "neutral" dissemination of the only scientific results of newton. francesco algarotti explains newton’s prism experiment to ladies 35 color culture and science journal vol. 12 (2) doi: 10.23738/ccsj.120204 condemned by decree of april 1739, the book appeared in the 1744 edition of the index librorum prohibitorum (list of prohibited books). from 1746, the new prints presented a revised title (the last was dialogue on the neutonian optics) and significant variations. algarotti added a new dialogue, which he envisages to happen several years after the others, and an appendix containing some scientific dissertations. from 1750, algarotti replaced the proemio, originally dedicated to fontenelle, with another dedicated to frederick ii, king of prussia in which his literary style became more austere and academic. (salvadé, 2010) the distinguishing feature of newtonianism for ladies was that algarotti presented theory about the nature of light and colours according to newton’s experiments. algarotti shares, with galileo and locke, the same idea about the scientific value of experience, in antithesis with the cartesian method. in the book, he presented newton as a follower of the galilean tradition and the first modern philosopher. fig. 4. newton’s opticks the description of some of newton’s experiments on the nature of light and colours in the form of a genteel dialogue has great educational value, because it does not demand any geometrical or algebraic knowledge. from this point of view, the literary quotes are totally justified and meaningful. at the beginning of the first dialogue, algarotti turns to the marquise declaiming the following verses: the sevenfold light whence ev’ry pleasing charm of colour springs, and forms the gay variety of things from the composition of these seven colours in a direct ray from the sun arises the white or rather golden colour of light: that if this direct ray from the sun is refracted by a certain glass called a prism, these rays of which is composed differing in colour and differ also in degrees of refrangibility. in fact, algarotti intends to speak about optics and in particular wants to explain to the marquise how light, according to newton's opinion, is not simple and pure but like each ray of sun is a bundle composed of red rays, some orange colour, yellow, green, indigo and violet. algarotti then also explains reflexion and refraction. reflexion happens by a collision of the globules of light with the solid part of bodies, these globules are repelled back again as a ball rebounds when it is struck against the earth. refraction is caused when the globules of light passing through air, water, glass, meet with the pores and cavities of these bodies, so that the ray, which is only a chain of globules, breaks and turns out of its proper path and takes a different direction from what it had before. he tells the lady to think she is in a room, completely in the dark except for a narrow, round glimmer from which a ray of sunshine comes. at a certain distance from the glimmer, there is a glass prism, which receives through it that glimmer of light. the prism must be situated so that a face is looking at the ceiling of the room, another face at the glimmer and the third face at the wall facing the glimmer. one of the edges must face the floor. the ray of the sun, which penetrates the face that looks at the glimmer, comes out of the face that looks at the wall so that the prism refracts it and sends it straight over the wall of the room that faces the glimmer. the luminous trace is no longer that which the straight beam impressed on the floor. the trace is white and almost round, while the second is five times longer than the width, it is four-sided and rounded at the ends and the light is broken down into seven colours. the colours are arranged as follows: first red, then orange, then yellow, green, blue and indigo and finally purple. turning the prism, a little around itself the ray of sun becomes more or less oblique to the face on which it falls. thus, the order of refraction can be changed and the coloured image can be seen rising or falling from the wall. stop the prism when the emitting ray is equally inclined to the faces of the prism. then the colours are even more beautiful and bright. né il superbo pavon si vago in mostra, spiega la pompa dell’occhiute piume, né l’iride si bella indora e innostra. il curvo grembo e rugiadoso al lume [2] 6. conclusion in italy, francesco algarotti was the first author of a text popularizing newton’s theories. following the principles of francesco algarotti explains newton’s prism experiment to ladies 36 color culture and science journal vol. 12 (2) doi: 10.23738/ccsj.120204 enlightenment, algarotti, by literary quotes or his own verses, achieved the purpose of disclosing scientific culture to women and lower classes.the civil tension and the true will of renewal, which is easy to detect in the first edition—emphasizes experimental philosophy as a methodology valid in every field, from natural research to political practice—which are lost in a "neutral" dissemination of the only scientific results of newton. even today, algarotti's method of dissemination could help pupils to understand principles of newton's physics. 7. conflict of interest declaration the authors declare no conflict of interest related to this publication 8. funding source declaration this research did not receive any specific grant from funding agencies in the public, commercial, or not-forprofit sector. 9. short biography of the authors paola magnaghi-delfino •assistant professor of mathematical analysis at politecnico di milano, member of the laboratory fds of the mathematics’ department. she is co-founder of iamai (international association of mathematics and art – italy). the fields of research of paola are the relationships between mathematics and arts and history of mathematics, on these themes paola produced several papers in collaboration with mele and norando. tullia norando associate professor of mathematical analysis at politecnico di milano, member of the laboratory fds of the mathematics’ department. she is co-founder of iamai (international association of mathematics and art –italy). the fields of research of tullia are the relationships between mathematics and arts and history of mathematics, on these themes tullia produced several papers in collaboration with magnaghi and mele. giampiero mele architect, ph.d.at the university of florence, ph.d. at the université di paris 8. associate professor (università degli studi ecampus), professor of descriptive geometry (university of florence, politecnico di milano, university of ferrara). his fields of research are the relationships between geometry and arithmetic in historic architecture, and drawing in architecture and design. founder and president of iamai. notes [1] 1 inch=38 centimeters. [2] neither the superb peacock wanders in the exhibition, explains the pomp of the eyed feathers, nor the iris is beautiful and gilds it with its own. the curved womb is dewy by the light references algarotti f. (1737) il newtonianismo per le dame. it.wikisource.org/wiki/il_newtonianismo_per_le_dame (accessed: 24 may 2019). algarotti f. (2017) opere del conte francesco algarotti. delhi: reink books. algarotti, f. (1737) sir isaac newton's philosophy explain'd for the use of the ladies, in six dialogues on light and colours. play.google.com/books/reader?id=qg1baaaaqaaj&hl=it&pg=gbs.pa 1. (accessed: 24 may 2019). baetjer k. (2003) ‘venice in the eighteenth century’, in heilbrunn timeline of art history, new york: the metropolitan museum of art. http://www.metmuseum.org/toah/hd/venc/hd_venc.htm. (accessed: 24 may 2019). barbetta m. c. (2013) il newtonianesimo per le dame di francesco algarotti, il limite e l'infinito: studi in onore di antonio moretto. pp.121138. bologna: archeotipolibri. giudice f. (2009) lo spettro di newton. la rivelazione della luce e dei colori. roma: donzelli editore. lowengard s. (2005) the creation of color in eighteenth-century europe.new york: gutenberg-e home columbia university press. massarenti a. (2006) ‘newton’. milano: il sole 24ore, officine grafiche calderini. murzi m. (2014) ‘algarotti e la divulgazione dell’ottica di newton’, rivista di studi italiani, pp252-274. newton i. (1704) opticks: or, a treatise of the reflexions, refractions, inflexions and colours of light. london: sommel smith and benjamin walford. salvadé a. m. (2010) ‘francesco algarotti. newtonianismo per le dame’. l’incipit e la tradizione letteraria italiana. seicento e settecento, pp.209-216. lecce: pensamultimedia editore. westfall r. (1962) ‘the development of newton's theory of color’. isis, 53(3), pp. 339-358. 73 colour culture and science journal vol. 11 (2) doi: 10.23738/ccsj.110208 under the lens of isle: leonardo da vinci’s "landscape" drawing analysed by colourimetry marco gaiani1, fabrizio ivan apollonio1 1 department of architecture, alma mater studiorum university of bologna, bologna, italy. marco.gaiani@unibo.it, fabrizio.apollonio@unibo.it corresponding author: marco gaiani (marco.gaiani@unibo.it) abstract on the occasion of the fifth centenary of his death, the museo leonardiano da vinci celebrates its anniversary with the exhibition "leonardo a vinci. at the origins of the genius" which includes the exhibition of the drawing of landscape, dated august 5, 1473, kept at the gdsu of the uffizi galleries in florence. the university of bologna has been asked to make a 3d rendering of the drawing that could be used as a substitute, capable of investigating, describing and communicating the drawing, its methods and contents, faithfully reproducing its form, characters and appearance. the answer was the isle application, a means of observing and understanding, interpreting and envisioning drawings and therefore able to penetrate the secrets of leonardo's landscape. technically, isle aims to provide a unified answer to two distinct and complementary questions: the first is the creation of drawing archives that can accurately describe the information of the original analogical physical system; the second is related to the methods for the collection and rendering of 3d drawings, i.e those systems and techniques that allow for the reproduction and systematically show a perception of the form three-dimensionally thus creating a visual evaluation of the current state of conservation of the drawing, of the superimposed sedimentation and of any restorations received over time. this paper describes the experience and results. keywords leonardo da vinci, antique drawings, colour analysis, 3d, visualisation, mtf, led light. received 09 october 2019; revised 23 november 2019; accepted 28 november 2019 under the lens of isle: leonardo da vinci’s "landscape" drawing analysed by colourimetry 74 colour culture and science journal vol. 11 (2) doi: 10.23738/ccsj.110208 1. introduction on the occasion of the fifth centenary of his death, the museo leonardiano da vinci celebrates its anniversary with the exhibition "leonardo a vinci. at the origins of the genius" which includes the exhibition of the drawing landscape, dated august 5, 1473, kept at the gdsu of the uffizi galleries in florence (inv. 8p). it is a small representation written on a sheet of 196x287 mm, i.e. about an a4, in pen and iron gall ink of four different shades, red stone and lead tip on paper, which presents the famous depiction of landscape on the front and a series of figures on the back. a complex system of signs that has never allowed a definitive answer to a series of questions that still remain open today. what is inside that tiny drawing, smaller than an a4 format and 50 cm away already concealing secrets to the human eye? what did leonardo think when he drew the landscape? what does the landscape represent? the valdarno as some people want it to be? or the marmore falls as others want? and how did leonardo manage to draw his subjects so quickly and so effectively, still today incredible to the vision? was it the work of leonardo alone, or, as some scholars claim, is the sheet an extraordinary example of dialogue between andrea del verrocchio's collaborators and perhaps verrocchio himself? in order to try and answer these questions on the occasion of the exhibition, the university of bologna has created a three-dimensional digital communication artefact called isle, which allows the drawing to be reproduced with perceptual fidelity to the shape, characters, colour and appearance on a 55" 4k touch table, interacting with it as if it were in the hands (fig. 1). isle, born from a series of experiences conducted over a decade (gaiani et al. 2011; gaiani et al. 2012, apollonio, et al., 2015), using five photographs, reconstructs the three-dimensionality of the drawing, rendering it digitally as a computer graphics image under all conditions of lighting and observation, with perceptual fidelity of high colour and a resolution of 50 µm. fig. 1. leonardo da vinci's landscape drawing seen through isle. in order to faithfully reproduce the original isle, rather than use the traditional solutions based on 2d (i.e. very high resolution images) or 2d1/2 (e.g. reflectance transformation imaging techniques (malzbender et al., 2001)), it adopts a completely 3d paradigm, relying on the concept of 'total appearance' (wilkie, et al., 2009). the developed solution aims to reconstruct the entire spatial reflectance of the artefacts in order to appreciate not only the graphic characters of the work (signs and traces), but also the undulations of the paper, as well as the critical conservation of the sheet due to corrosion of the acidity of the inks and other accidents, such as exposure to light and other atmospheric agents, which have affected the artefact over time. from an operational point of view, the solution consists in the evaluation of a bidirectional scattering distribution function (bsdf) and its rendering in real-time rendering (rtr), using a simple acquisition scheme and not harmful to the design. the system follows in its entirety the one used in leonardo's previous experience of vitruvian man (gaiani, et al., 2015), introducing, however, countless innovations, starting from the same basic scheme, for the desire to improve some characters that already at the end of the previous experience had shown the possibility of improvements: the accurate reproduction of colour, the morphological configuration of the design, the reflection model of paper and ink. from a technical point of view, isle is composed of six sub-systems: a. an effective 48-bit colour capture, using an integrated camera-back scanning solution: the rencay direct camera systems 24k³. this camera features a kodak kli-8023 ccd sensor trilinear rgb with 8000 pixels per sensor, for a native resolution of 13000 x 8000 pixels and a maximum resolution of 39000 x 24000 pixels. the pixel pitch is 9 μm which allows a resolution limit of 55 lp/mm with 60% contrast. the lens used is a rodenstock apo-macro-sironar-digital 120mm. f/5.6 72×96 performing excellent resolution even at the corners, limited distortion and uniformity of illumination; b. a lighting system based on individual high flux leds with white light relio2 (https://www.relio.it/), an illuminator emitting continuous spectrum light at a cct of 4000°k, a neutral white with high colour rendering, a brightness of 40,000 lux at 0.25 m and a cri > 95%. it avoids the typical problems of fluorescent illuminators that do not allow the acquisition of information at certain wavelengths of light (fig. 2) in addition to the presence of harmful ultraviolet (uv) and infrared (ir) rays; under the lens of isle: leonardo da vinci’s "landscape" drawing analysed by colourimetry 75 colour culture and science journal vol. 11 (2) doi: 10.23738/ccsj.110208 fig. 2. spectral power distribution of fluorescent light tubes for photographic use (left) compared to that of the relio2 4000k lamp (right). c. a computational model to give micro and macroscopic fidelity to the surface within a rendering window based on the opengl graphics libraries; d. a software allowing an excellent colour correction from raw images to faithfully reproduce the colour; e. a solution to visualize the high-fidelity communication artefact using a rendering engine low-cost and portable on multiple devices (wall, monitor, pc, tablet, smartphones); f. a visualization interface for visitors to museums and exhibitions based on touch and gestures usual because they are borrowed from those of smartphones. using isle, landscape drawing has been examined as a graphic artefact through visual and colourimetric analysis. the paper shows the analysis results and a technical description of isle features more closely related to the type of analysis proposed. 2. capture sharpness and resolution the determination of the artist's tracing properties can be qualified only in the presence of an appropriate effective resolution of the images, in order to ensure the reproduction of all significant details present in the original document on the display device. two parameters must be measured to define the resolution: spatial detail and its preservation. the necessary spatial detail can be established by a preliminary analysis of the document (macdonald 2010). in this specific case, as already emerged from the analysis of other of his drawings, the trait of leonardo's drawings is particularly challenging. the reference data reveal, in fact, sign values at a minimum of 90 μm thickness, while the wire rods making up the paper have a size of about 700 μm. following shannon-nyquist's sampling theorem, the resolution required to faithfully represent the structural characteristics of the landscape is at minimum 565 ppi. the measure of its conservation has been realized at different spatial frequencies through the measurement of the frequency transfer function (mtf modulation transfer function) (jacobson, 1995), estimated by the spatial frequency response (sfr), i.e. the normalized module of the fourier transform of a line diffusion function (lsf) (ridler and calvard 1978). the measurement of mtf is coded by the iso 12233:2000-2017 (iso 2017) standard, which provides for three metrological protocols, the most common of which is the one providing for the measurement of the slanted edge (burns 2000). the method, which produces the edge spread function (esf) by scanning the image of an edge, has several advantages: the distance between camera and lens does not fit into the equation that converts the image to mtf response (it is invariant at scale); inclined edges take up less space and are less sensitive to noise than sinusoidal models; mtf can be measured at nyquist frequency (0.5 cycles / pixel) thanks to the binning/oversampling algorithm. the characterization of the effective resolution was then carried out by measuring the mtf using an iso 12233:2000 target size 200 x 356 mm and the software imatest studio version 4.5. the choice of the target defined in the 2000 standard has been made both because its defects do not particularly affect the results in the case in question, and because of the possibility of comparing the current results with those obtained in previous under the lens of isle: leonardo da vinci’s "landscape" drawing analysed by colourimetry 76 colour culture and science journal vol. 11 (2) doi: 10.23738/ccsj.110208 experiences with the same shooting system and similar subjects. base acquisition values venice florence mtf50 0,099 cy/px 0,1425 cy/px lw/ph 1600 2280 mtf10 0,26 cy/px 0,415 cy/pxl mtf at nyquist 0,00602 0,0545 10-90% rise 5,37 px =1490 per ph 4,34 px =1845 per ph effective resolution 335 px/inch 483 px/inch tab. 1 vertical mtf. comparison of mtf values in the two acquisitions: vitruvian man, 2014; landscape, uffizi, 2018. the reference parameters were essentially two: mtf10 and mtf50. the mtf10, i.e. the frequency associated with the mtf response point of 10%, is used to evaluate the resolution capacity, i.e. the maximum resolution. the mtf50 is the most suitable parameter of image sharpness and to compare the sharpness of cameras and lenses. in addition, the mtf technique has been used to evaluate the appropriate sharpening of image to remove the lens and sensor blur not achieved in-camera using an image editor and unsharp mask filter (um). um filter principle of operation is based on the fact that the contours of objects are locally areas of high contrast. in particular, an iterative system for finding the parameters of the um was developed to minimize the phenomena of oversharpening and undersharpening, as proposed in (williams and burns, 2008). ultimately, the response with respect to a slanted edge in terms of rising distance (rise 10-90%) and the mtf curve as function of the spatial frequency expressed in units of cycles per pixel, measured by the values of mtf50 and mtf10, were calculated. the average spatial resolution (horizontal and vertical) on an acquired image size of 13000 x 8000 pixels corresponding to a sampled area of 205.1 x 333.35 mm corrected with um (values: intensity: 150; radius: 1.00; threshold: 4.00; edge offset: 0.00), was for the rise 10-90% = 4.00 pixels; in the frequency domain was obtained an average mtf50 = 0.2445 cycles/pixels and an average mtf10 = 0.336 cycles/pixels, corresponding to an effective resolution of 740 px/inch (tab. 1) capable of resolving details of 60 μm, finer than the minimum required. finally, the mtf values were compared with those recorded in 2014 on the occasion of the acquisition of the vitruvian man (apollonio et al., 2015). the data resulting from the two experiences, despite the inevitable operational differences regarding some components of the equipment (such as the optical group of the target), confirmed the reliability of the procedure, and showed a slight improvement in the performance of the entire acquisition system in terms of quality of resolution, with an increase in the value of mtf50 and mtf10 and consequently of that of the actual resolution. 3. colour correction a fundamental problem in the digital acquisition and reproduction of fine art drawings is the chromatic and tonal definition of the graphic work which, in our solution, must be framed within the more general topic of the complete definition of the material's properties, i.e. the bidirectional scattering distribution function (bsdf), so that it can be identified in the acquisition and reproduction of a colour map and a rendering algorithm. since the digital rendering of the reflection of a surface requires strong simplifications of the physical behaviour of light and its interactions with the surface in order to be calculable in a reasonable time, in the development of isle we have set ourselves the acceptable objective of restoring at least perceptual fidelity to the colour. for this reason, we followed a colourimetric approach based on the colour correction (cc) of the acquired raw images, following a target-based technique, a particularly efficient solution when it is possible to define the requirements of the images and carry out the image under similar conditions of the target and of the subjects to be represented, exactly our case. acquisition values adding unsharp mask filter venice [intensity: 200; radius: 1; threshold: 6,00; edge offset: 0,00] florence [intensity: 150; radius: 1; threshold: 4,00; edge offset: 0,00] venice florence mtf50 0,1699 cy/px 0,1791 cy/px lw/ph 2718 2865 mtf10 0,373 cy/px 0,452 cy/px mtf at nyquist 0,137 0,067 10-90% rise 4,99 px =1604 per ph 4,76 px =1682 per ph effective resolution 575 px/inch 683 px/inch under the lens of isle: leonardo da vinci’s "landscape" drawing analysed by colourimetry 77 colour culture and science journal vol. 11 (2) doi: 10.23738/ccsj.110208 a fully automated cc solution developed by our team, socalled shaft (sat & hue adaptive fine tuning) (gaiani and ballabeni 2018), was adopted for isle. it is based on an x-rite colorchecker classic target (mccamy et al., 1976) (the expected values of which were obtained by measuring the patches of the colorchecker used using a minolta cm-2600 d ball spectrophotometer) and a twostage cc process. a first correction is made using a perchannel polynomial fitting algorithm based on the matlab weigthed polyfit (x,y,n) function. the algorithm is explained in detail in (gaiani, et al. 2017). a second correction is made using the actual shaft procedure weigthed polyfit (x,y,n). the process adopted follows the usual five rules of colourimetric imaging: 1. correlated colour temperature (cct) of the illumination 5000°k (d50 workflow); 2. optimal exposure; 3. colour profile based on ∆e minimisation with excellent brightness accuracy; 4. target-independent validation used to create the camera profile; 5. coding space capable of not cutting object colours. as final encoding colour space we selected the srgb-iec 61966-2-1 whose values are defined with respect to cie illuminant d65. its potential contraindications (nonlinearity, size smaller of the colour space perceived by humans) do not influence the colour quality of isle rendering. the landscape not present badly representable colours by the srgb colour space. in fact, iron gall ink, black chalk, red chalk and paper have colours completely inscribed in the srgb colour space, without the need for colour clipping or remapping. on the other hand, the use of srgb has a number of advantages including, mainly, full support from the 3d graphic api used (opengl) and 100% displayability on today's monitors. the cc workflow is instead completely realised in the linear space ciexyz. the reason is in the observation that, using this colour space, the errors calculated by the least squares fitting algorithms correspond very well to the deviations of the images corrected to the original, so fewer numerical deviations correspond to more visually accurate images (lukac and plataniotis 2007). for the evaluation of the error in the correction both during the cc process and in the final validation, the colour metric issued by the cie in 2000 (sharma et al. 2005), calculated for each colour patch, was used. as suggested e.g. in (williams and burns, 2016), a metric dispersion analysis was used in addition to the evaluation of the average δe00. the results show an average value of δe00 = 2.21, an average brightness accuracy of δl00 = 0.59 and an exposure error of 0.02 f-stop (fig. 3). fig. 3. evaluation of the results of the cc using equal weights of all patches (above) and different weights between the various patches (below) however, the evaluation of the δe00 error on the individual patches led to significant problems in the area of the yellow under the lens of isle: leonardo da vinci’s "landscape" drawing analysed by colourimetry 78 colour culture and science journal vol. 11 (2) doi: 10.23738/ccsj.110208 (for the d3 patch we reported a δe00mean = 4.2) and partially of the red (for the c3 patch we reported a δe00mean = 2.8), confirmed by direct and comparative observation of the correct images and the original drawing. this restates the observation of many authors that the cc procedure using standard colour targets is problematic when the object to be reproduced is characterized by a limited range of colours close to neutral colours, which is the typical case of the drawings (berns et al. 2005, trumpy 2010). the experimentation of some solutions proposed in the literature, such as the construction of a personalized chromatic target with patches empirically chosen within the palette of colours present in the original (williams and burns, 2012), has shown a strong aleatory in the choice of candidate colours, as well as the verification using a different target from the original one has led to unsatisfactory results for the difficulty to reproduce measured distributions of colour not too dissimilar (williams and burns, 2016b). a different procedure was therefore preferred: a. from the images of the drawing (recto and verso) obtained from the standard cc process, corrected images were created manually using adobe photoshop on two different calibrated monitors (nec spectra view 2690 and spectra view reference 302) respectively at 5000°k and in srgb colours for visual comparison with the original drawing placed next to the monitors and illuminated with the led lamp used for the acquisitions until obtaining perceptively marginal differences at the prolonged observation of five expert users; b. on a raw image the cc process was carried out with shaft but giving different weights to the patches of the colorchecker classic emphasizing the neutral a4-f4 and those of the colours closest to those present in the drawing. this procedure has been repeated for various weights; c. the images of the drawing thus obtained were compared by 20 expert subjects with respect to the original drawing illuminated with the led lamp used for the acquisitions on the two nec spectra view monitors calibrated as above (5 people) and with respect to the correct image manually (20 people of which 5 on the two nec spectra view monitors, 15 people on the lacie 526 monitor calibrated with respect to the srgb colour space). considering that the changes in ambient light only affect the perception of absolute colour, but have no effect on the relative sensation of colour difference (hao et al. 2011), the verification was held in two differently lit environments capable of allowing an observation as close as possible to that defined by the standard iso 3664:2009 (iso 2009). all observers found perceptually marginal differences in the prolonged observation of the images in which was assigned a weight 2 to the patches a1, b1, a2, f2, c3, d3 and a4, and a weight 3 to the patch f4. for this cc solution we achieved a δe00mean = 2.25, a δl00mean = 0.63 and an exposure error of 0.00 f-stop which corresponds to the indistinguishability from the real on a calibrated monitor. moreover, for the d3 patch we obtained a δe00mean= 2.88 and for the c3 patch a δe00mean= 2.27 (fig. 3). 4. the landscape seen through isle here we briefly summarise only some of the main characters of the drawing compared with those of another drawing by leonardo: the famous study of proportions of the human body, previously acquired and analysed (apollonio, et al., 2015). as main literary reference were used for the first drawing the alessandro nova's essay "addj 5 daghossto 1473" (nova 2015) and for the second one a paper by loretta salvador, the last restorer of the drawing (salvador 2009). the landscape drawing has laid wires placed at regular intervals, horizontally, of a size of about 800 μm (13 lines per 10 mm approx.). these laid wires are well distinguishable on the front and are almost indistinguishable on the back, demonstrating that this was the part of the paper most treated, contrary to what happens in vitruvian man who shows the laid wires on the back, while they are not perceptible on the front. chromatically, the paper is very similar to that of the drawing in venice today, because it took three areas of 250 x 150 pixels in more parts of the drawing (front of both) blurred using a bilateral filter (paris et al. 2009) and normalized the brightness, the average values read were for the landscape l*a*b*= 87 4 11, for the vitruvian man l*a*b*= 87 4 13. the two drawings, on the other hand, have different average luminosity, for the landscape l*= 82, for the vitruvian man l*= 87. this last circumstance may be due to different causes, which may range from exposure to sunlight to the treatment of paper. the comparison between the back of the 8p and the front of the vitruvian man shows identical colourimetric values. taken three areas, as in the above analysis, the average values are l*a*b*= 87 4 15, supporting the hypothesis that the main face of the landscape is the one that is currently commonly identified as verso. under the lens of isle: leonardo da vinci’s "landscape" drawing analysed by colourimetry 79 colour culture and science journal vol. 11 (2) doi: 10.23738/ccsj.110208 point 1 point 2 point 3 point 4 point 5 point 6 point 7 point 8 point 9 l 55 54 54 47 45 44 41 42 47 a 12 12 16 12 12 13 13 11 10 b 26 24 26 16 14 14 16 13 14 tab. 2 leonardo da vinci, landscape, colourimetric analysis of inks from images acquired, recto. point 1 point 2 point 3 point 4 point 5 l 36 36 37 44 44 a 5 9 7 12 10 b 8 10 12 17 15 tab. 3 leonardo da vinci, landscape, colourimetric analysis of the inks from the images acquired, towards the colourimetric analysis of the inks identifies the use of two distinct substances that constitute two distinct graphic layers of the drawing. the first one includes the general layout of the composition, with what has been interpreted as the fucecchio marshes, the hill on the right, the mountains in the background, the trees, and the layout of the hill on the left. the second instead includes the spur above the squared rocks, the waterfall, a series of retouches in the lower part, the confluence between the two rivers, and what has been recognized by some authors as the castle of montevettolini. table 2 shows the values in the l*a*b* scale for the samples extracted, located in the same table and fig. 4 shows details extracted from the application that well show the realization with two different inks/instruments. fig. 5 divides the traits of the drawing into two large families identified using the k-means clustering segmentation algorithm based on colour (arthur and vassilvitskii 2007). fig. 4. leonardo da vinci, the landscape seen through isle: different inks/instruments on the front of the drawing. fig. 5. leonardo da vinci, the landscape seen through isle: different inks/instruments on the front of the drawing. according to the colourimetric analysis, also the back of the drawing is made with two different inks. their today colour is even different from those present on the front. an ink is used to draw the naked man in movement, the head in profile on his left and the words "jo morando dant[oni]o sono chontento". the second ink is used to sketch the mountainous landscape with the bridge over a stream and the foliage of the trees. table 3 shows the values on the l*a*b* scale for the samples extracted. compared to vitruvian man, in whom two different ink are used to write and to draw the variation of chromaticity of the inks in the landscape is much wider. this variation can be appreciated also by non-expert observers while the chromatic differences of inks used in the drawing today in venice are much less evident and perceivable only by an expert observer. as for the stroke, on the front of the 8p we can see the use of two different types of pens, one used for the background layer with a stroke width of 0.7-1.5 mm (and usually 1.2 mm), and one for the foreground layer with a width of 1.22 mm (and usually 1.7 mm). under the lens of isle: leonardo da vinci’s "landscape" drawing analysed by colourimetry 80 colour culture and science journal vol. 11 (2) doi: 10.23738/ccsj.110208 it is a very different technique from the one used in the vitruvian man where the freehand strokes have an almost constant width of 0.3 mm and the straight strokes drawn on the groove have an almost constant width of 0.2 mm, as that drawing is without smudges, "perfect for a technical drawing that had to "prove" the proportions" (salvador 2009). 5. conclusion the observation of the landscape drawing through the colourimetric and the stroke analysis allowed to focus on features otherwise difficult to observe. it emerges, completely in line with the alessandro nova statement, that this drawing is a complex graphic system, certainly produced in several phases, a sort of work-in-progress that has generated various figurations, of which what appears today on the front is the most striking result for the character of completeness despite it is the result of at least two different tools each of which is used in a specific and homogeneous area of the drawing. 6. conflict of interest declaration the authors declare no conflict of interest. 7. acknowledgment we would thank the director of the gallerie degli uffizi in florence eike schmidt, the director of the museo leonardiano in vinci roberta barsanti that allowed this work. a special thanks to the members of the research group: andrea ballabeni, giovanni bacci, marco bozzola, simone garagnani, roberto palermo. 8. short biography of the author(s) marco gaiani full professor of architectural representation at university of bologna, dept. of architecture, past director of the indaco dept. of the politecnico of milano and dapt dept. of university of bologna. a specialist in 3d computer imaging, modelling and visualization for heritage and archaeology, he was one the first developers/user of laser scanning and automatic photogrammetry technologies in the ch field. fabrizio ivan apollonio full professor of architectural representation at university of bologna, dept. of architecture, and phd in survey of the existing built heritage (university of ancona). his main research topics lies on virtual reconstruction, semantic modelling and application in the field of ict to cultural heritage and development of information/cognitive systems aimed to fruition, study and documentation of ch. references apollonio, f. i., clini, p., gaiani, and m., perissa torrini, a. 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(2016b) ‘color correction meets blind validation for image capture: are we teaching to the test?’, in proceedings of is&t international symposium on electronic imaging, pp. 218.1-218.4. 82 color culture and science journal vol. 12 (1) doi: 10.23738/ccsj.120110 approaching ecological ambiguity through a non-divisionary understanding of colour in art yulia kovanova1 1 edinburgh college of art, the university of edinburgh, edinburgh, scotland, united kingdom. yulia.kovanova@ed.ac.uk corresponding author: yulia kovanova (yulia.kovanova@ed.ac.uk) abstract in the face of the current ecological uncertainty, we are often confronted with discomforting ambiguity: the boundaries across human and nonhuman worlds continue to blur. in response, the discourse of environmental humanities looks at reframing existing approaches of being in the world. it proposes a focus on ‘entanglements’, which prefigures turning away from individualistic and discordant thinking towards a mode of operating that highlights connection and relationship. much like every aspect of our interconnected world ecology, colour too is subject to the current environmental crisis. with unprecedented rates of extinction, we are losing colours and unique colour combinations in our environment. though colour is an ambiguous, unstable and constantly shifting phenomenon, colour studies have traditionally favoured a divisional approach, dividing the spectrum into categories and individualised colours. in this drive towards divided categories, we often forget that we are dealing with one spectrum, and that strict division is artificial. a non-divisional approach to understanding colour falls closer to the natural aesthetic experience of the visual field and corresponds with the interconnected ecological approach. the author aims to link this non-divisional approach in colour to ‘entangled’ environmental thinking and examine this through art practice as an effective tool for comprehending invisible ecological interconnectedness in the time of the ‘anthropocene’. the article concludes that colour offers a powerful tool for exploring ecological entanglements, offering entry into positive ambiguity. keywords ambiguity, art, colour, ecology, entanglements received 01 november 2019; revised 06 december 2019; accepted 07 december 2019 approaching ecological ambiguity through a non-divisionary understanding of colour in art 83 color culture and science journal vol. 12 (1) doi: 10.23738/ccsj. 120110 1. a spectrum of life environmental humanities has emerged as a response to the growing environmental challenges facing life on earth today, out of the need for a more balanced approach to environmental issues. the interdisciplinary nature of the field, combining the humanities with social and environmental sciences, calls for new ways of understanding humanity’s place within the world: it aims to resituate the human within the wider ecological structure, challenging a pervasive anthropocentric ontological exceptionalism. the key proposition of the environmental humanities is to focus on entanglements between human and other-than-human agencies, moving away from the divisionary individualistic mode and towards interdependencies. entangled relations between human and non-human worlds are situated at the core of environmental humanities approach (rose et al. 2012). emerging out of biology, ecology offered a specific study of the interrelatedness of all organisms and their physical surroundings. however, despite the deepening of human knowledge in this area, our connection with the surrounding world has dissipated further. one of the world’s leading anthropologists, tim ingold (2018), feels that science has lost the radical ecological awareness it previously had. once championed by science, this awareness, ingold believes, has found a home in the arts. within this context, exploring the notion of ambiguity through art practice could be an effective way of looking at the challenging and multifaceted contemporary ecological situation. in their book rethinking pluralism: ritual, experience, and ambiguity, adam seligman and robert weller argue that “all quests for certainty contain inherent dangers and limitations.” the authors do not deny the construction of categories as invalid or incorrect, “constructing categories is one of the fundamental skills that make up our human capacity for culture,” but wonder “how to live with ambiguity while still retaining order” (seligman and weller 2012:13). exploration of the ambiguous is especially important now that humanity has stumbled into the age of the ‘anthropocene’, defined as the epoch in which humans have become the dominant global geophysical force (steffen et al. 2007). one of the foremost contemporary thinkers on the state of ecology today, timothy morton, argues that we live in a time of ambiguity and a resultant anxiety. he notes that, “the basic affect of an ecological era – that is, the era we have been realising we have been inhabiting, namely the anthropocene – is anxiety” (morton 2018a:232). morton, suggests that ambiguity is precisely what we need to expose ourselves to today, “true and false might not be that different,'' says morton, “ambiguity is the space in which really true things can be said. ambiguity isn’t vagueness, ambiguity is an accuracy signal” (morton 2018b, video file 00:32:16). within this context, contemporary art practice and colour explored through a non-divisionary approach could contribute towards these important discussions and help unravel the more ‘entangled’ thinking on being a part of the world. 2. the in-betweenness of things through the normative objective, and hence disconnected, scientific approach, with division into lists and taxonomies, a separation between the human and the rest of the world becomes formally established in our thinking. art practice, with its core methodology of paying and directing attention, through openness to and abiding by the unknown, has the capacity, as a shared experience, to help bridge the perceptual gap that has grown out of the disconnection inherent in taxonomic methods. exploring the in-betweenness of things and how seemingly separate objects, bodies and phenomena are entangled, a number of authors within the environmental humanities looked at various ‘borders’ and what reformulation of those might reveal. this opens up new possibilities of viewing and conceptualising some of the most pressing environmental and social issues today. a time of ambiguity may be a time when outcomes are not easily anticipated. now, more than ever, we are all aware of the rapid changes around us, but often unaware of how we should act. so, how do we allow ourselves to find comfort in the ambiguous? how could art practice and the exploration of colour and its dynamics aid this? in what way can the environmental humanities provide a powerful platform for this inquiry? the notion of entanglements could serve as a way into the space of ambiguity, in which art can physically manifest this ambiguity in relatable and emotionally resonant ways. timothy morton talks about art as a powerful tool for ‘ambiguity tolerance training’ (morton 2017). artistic practice lends itself perfectly as a platform for exploring the ambiguous. “uncertainty is typically not desirable in everyday experiences, but uncertainty in the form of ambiguity may be a defining feature of aesthetic experiences of modern art” (jakesch and leder 2009:1). artistic practice also offers a powerful tool for visualising the ecological entanglements which might not be obvious, or even visible to the human eye. there is a discrepancy between what happens within the environment and what we perceive as happening, with a large number of signals remaining unnoticed or misunderstood. anthropologist, cultural ecologist and philosopher david abram argues that a crisis in perception is one of the key reasons for ever-growing environmental approaching ecological ambiguity through a non-divisionary understanding of colour in art 84 color culture and science journal vol. 12 (1) doi: 10.23738/ccsj. 120110 concerns. reciprocity is one of the ways in which abram describes that ongoing interconnection, revealing the interdependencies between human and other-than-human worlds (abram 1997). if we need to break the restrictive conceptual and, more importantly, perceptual borders that maintain the threats, in order to generate an entangled state of being, then contemporary art practice, together with environmental humanities, becomes a powerful tool to help break these borders. the colour scientist and semiotician josé luis caivano proposed a new approach for understanding colour – a gradualist hypothesis – whereby the focus lies on “the moments of transition, gradations and transformations that allow moving from one category to another, with a better understanding of how the relationships are produced and the ways in which those differences occur” (caivano 2018:1). rather than employing divisional approaches to understanding colour, and visual phenomena in general, caivano’s gradualist method rejects the traditional focus on divisional categorisation and so falls closer to the natural experience of the visual field and how life on earth operates from the ecological perspective. colour, as one of the key instruments of visual perception, explored through contemporary art practice, offers a powerful tool for visualising the ecological entanglements which might not be obvious, or even visible to the human eye. a deeper exploration of the non-divisionary nature of colour could enable further insight into ecological entanglements, as well as offer artists a way of contributing to this understanding through the use of colour in works which seek to engage with entangled being. 3. colour extinction colour plays a key role in the aesthetic experience of visual perception and as a way of reading an environment and orienting within it. it is also a means of communication between the different species – between human and nonhuman worlds. understanding colour has most often been approached through the process of breaking the visual field down into categories, those of individual colours. while this divisional, micro-perspective has proven enlightening, the inclusion of a macro-perspective – investigating colour as a boundless spectrum – might offer a more holistic understanding of colour, articulating the interconnectedness of all things as observed through ecology. this interconnectedness we often fail to perceive when reality superficially appears to be so separated, leading to actions which are as destructive to ourselves as they are to the conceptualised ‘other’. as a species, we have a strong desire to resolve things, to understand, to uncover, to divide into categories. these categories are expanded and divided in increasing complexity as fields of knowledge develop. we also know, however, that there are many unknowns, and there always will be. the balance is too often skewed towards maintaining definition and classification, rather than also accepting that reality can be ambiguous, and the borders are somewhat enforced. ambiguity isn’t simply a blockage in the workings of knowledge caused by the lack of information necessary for classification, but also a vantage point to reconsider assumptions already made in the rush to certainty. colour and its dynamic nature might be a very useful tool for shared extrication from such assumptions in understanding ecology, with contemporary art practice attuned to ecological concerns enabling a productive platform for exploration. often perceived as a background, static property of objects, the influence of colour within the larger environmental context is rarely seen. in this crucial time of pressing environmental changes, there may be wide-ranging insights from greater exploration and analysis of spatial colour distribution. how can artists use colour to produce a particular effect, which in turn might present new insights about environmental processes and enhance people’s awareness of their environment. in 2017, the european space agency reported that the colour loss of the great barrier reef – or coral bleaching – can now be observed from space (esa 2019). knowing that, in nature, colour developed as a result of evolution to support life processes, the presence of colour, its richness and vibrancy, can be seen as a signifier of life (buether 2014). as species disappear, we lose the colours, and especially the particular colour combination of the departed organism. as an example, the carolina parakeet, a small neotropical parrot, which before 1918 spanned the forests of the united states, was the only indigenous species of the neotropical area within the us, and one of the only two indigenous parrot species in the us. its tantalising combination of a unique proportion of greens, yellows, reds and pale pink will no longer brighten the forests – having been declared extinct in 1938. the species loss over the last few decades has been so extreme that scientists are now considering we might be in the midst of the sixth mass extinction (barnosky et al. 2011). thinking of these losses, it raises the question of how many colours and colour combinations we have already lost. are the sci-fi visions of dystopic future with their achromatic landscapes our destined future? with a great number of species already gone, and a large number approaching ecological ambiguity through a non-divisionary understanding of colour in art 85 color culture and science journal vol. 12 (1) doi: 10.23738/ccsj. 120110 of those entangled with us, might we soon be caught in the same vortex. 4. artistic propositions the author’s recent work exploring ecological entanglements took the form of a series of art pieces investigating ecological interactions through colour and its spatio-temporal dynamics, reconsidering perceptual boundaries in search of new possibilities of how spaces are shared with non-human others. a series of abstract interactions entitled ‘grey to blue: ecological entanglements’ is explored through sculptural, photographic, moving image and sound-based works, drawing attention to the role of colour in the living world, while highlighting ecological loss and absence. these works articulate a positive ambiguity of representation, showcasing organisms in interconnected relationships and interacting with the environment, translated into indistinct colour forms that release our perception from preconceived separateness and division. taking inspiration from the natural world, these artistic propositions deal with the removal of borders and boundaries to create positive ambiguity. each artwork explores how everything is entangled, the in-betweenness of things and how seemingly separate objects, bodies and phenomena relate. fig. 1. detail of ‘torch ginger | lesser violetear’ installation, 2019. a sculptural installation (fig. 1) comprised of thin multicoloured wooden rods looks at the interaction of a hummingbird and its flower as the bird enters the flower to feed on nectar. the coloured lines representing the flower interpenetrate the colours of the hummingbird, creating one entangled spatial experience that absolves the audience of any need to distinguish one organism from another, accentuating the intractable relationship rather than binary forms. the audience can walk through the piece, thereby entering the hummingbird-flower experience and experiencing a frozen moment of ambiguity that conveys ecological interaction outside of feeder/food or sentient life/non-sentient life definitions. fig. 2. detail of ‘pawpaw | dark flower scarab beetle’ sculptural installation, 2019. photo: kenny lam. another installation (fig. 2) considers how flowers attract insects through their shape and colour. two-metre long rods, suspended vertically and painted in the colours of a pawpaw flower, open wide to allow visitors to enter the flower, duplicating the insect’s journey. this is the first piece experienced by the audience immediately upon entering the space, in which they mimic the path and colour attraction of the insect, without foreknowledge of the meaning, as an introduction to the proposition of entangled ecology of equal forms. a pile of soil spanning almost six metres in length is studded with casts of avocado stones of different shapes and sizes (fig. 3). the sculptures are absolutely white; their hue is missing – reflecting the extinct large mammals who would swallow and distribute the avocado stones. thousands of years ago, these great giants, such as the six-metre-tall giant sloth, would be attracted by the ripe avocados and mangos, swallowing the entire fruit with its pit, helping the plant to disperse its seeds far and wide. fig. 3. detail of ‘avocado | giant sloth’ installation, 2019. photo: machal jesionowski. approaching ecological ambiguity through a non-divisionary understanding of colour in art 86 color culture and science journal vol. 12 (1) doi: 10.23738/ccsj. 120110 those animals are long gone, yet the fruit has not caught up to this reality and continues to call for its lost partners. this collapse of deep time into a single representation brings the audience closer to a past that is directly linked yet feels impossibly distant. in the modern age of evershortening immediacy, it is perhaps the understanding of these direct links over deep time that could counter ecological anxiety. fig. 4. part of ‘avocado | giant sloth’ installation, 2019. photo: michal jesionowski. as the hue left the avocado pits, the actual avocado dye became one of the components of the three plaster casts on the wall overlooking the soil (fig. 4). this piece shows the various shades that can be derived from avocado dye. with the giant mammals gone, it is the role of the human as a surrogate to continue the work of helping these plants disseminate. a long strip of instant photos (fig. 5), suspended from the gallery ceiling and continuing on the floor, examines the changing colours of a mango as it ripens and spoils – from greens to yellows, oranges and reds. the mango fruits are lying on the forest floor waiting for their great giants, slowly transforming, slowly losing colour. fig. 5. part of ‘mango | stegomastodon’ instant image installation, 2019. the images are of an actual mango fruit as its colour changed, taken with in-camera blur. the details of the mango skin are removed, giving focus to the shifts in colour. hidden behind the changing colours, that fade out to the grey and black of mould, is the death of a relationship that flowered through evolution, now disrupted in a portent of further disruption inevitable through ecological collapse. fig. 6. ‘red silky oak | swallow-tailed hummingbird’ installation, 2019. photo: kenny lam. in a dark space is a blurred video of a brightly coloured swallow-tailed hummingbird and a red silky oak flower projected onto an imposing fractured ‘screen’ made of suspended paper tubes (fig. 6). as the hummingbird feeds from the flower, the border between each organism is obscured to the point of near-imperceptibility – only the colour and movement betrays a possible separation. accompanying the visual is a sound piece, a shimmering interpretation inspired by the sound of a hummingbird that carries the audience through the columns in a path within the hummingbird-flower relationship. the lights piece (fig. 7) is looking at the relationships between bees and flowers through colour and movement – as a single bee flits from flower to flower in search of nectar. the lights are mapped to the bee’s movement, while the colour of the flashing light is that of the flower, so the piece creates an experience of a bee-flower as one entity – alive only in coexistence. figure 7: ‘purple coneflower | rusty patched bumblebee’ installation, 2019. photo: kieran gosney. approaching ecological ambiguity through a non-divisionary understanding of colour in art 87 color culture and science journal vol. 12 (1) doi: 10.23738/ccsj. 120110 5. resting in the unknown the world operates as one interconnected ecology, yet we fail to see the connections. there is a discrepancy between what we perceive as happening in the environment and what actually occurs, with a large number of visual signals remaining unnoticed or misunderstood. this misconception left us in the space of ambiguity and led us into an environmental crisis, with the planet now largely contaminated by industrial pollution and species disappearing at an unprecedented rate. contemporary art practice has a crucial role to play in this time of environmental urgency, when an increased understanding of often invisible processes happening within the environment is a requirement. focusing on the gradualist approach to colour, alongside the idea of entanglements, has the potential to rearticulate the role and possibilities of contemporary art practice within the larger perceptual reframing efforts in response to key environmental issues. in paying closer attention to entanglements and recognising how interdependent we are in the wider web of life, the agency of the human can be reconsidered and de-centred. searching for that moment of ambiguity, resting in it, living in it, and finding comfort – oscillating at the biting point between sharpness and blur; like settling down in a foggy land, where the spaces between – the invisible – thicken, masking body and landscape; looking for those spaces, spending time in them, where thoughts do not fail to grasp onto separated elements; then slowly, as the fog dissipates, one might still embody that feeling of togetherness, fully entangled, and proceed the journey in gratitude and in kind to that larger self. this oscillation is what might allow us to be present in the world of forms and move into the fully entangled and interconnected experience of life as ecology describes it, but which is too challenging to perceive merely through the senses. vision is what so often misleads us, like the elusive and ambiguous nature of colour as light. as much as it is wonderful to hold onto something, there is value in learning to completely let go in the unknown, to trust, and act with care and attention. 6. conflict of interest declaration the author certifies that she has no actual or potential conflict of interest, including financial, personal or other relationship with other people or organisations in the prior three years that could inappropriately influence, or be perceived to influence her work, and no financial/personal interests have affected the objectivity of the author. 7. funding source declaration the author received funding from edinburgh college of art, the university of edinburgh, scotland for the phd research related to author-initiated investigation of this topic. 8. acknowledgment many thanks to edinburgh college of art, the university of edinburgh and hope scott trust for supporting the development, production and presentation of the work for the exhibition. in planning and developing the installations, the author worked in collaboration with architects yipei tan and xinren zhou, as well as shona yu for the video projection screen. the sound was composed by lars koens. the light installation was produced in collaboration with siyao zhou. technical assistance through the exhibition was provided by kieran gosney and vajid ali. 9. short biography of the author yulia kovanova is a siberian-born, scotland-based artist and researcher. her practice currently focuses on the investigation of ecology of colour and its dynamics, the ideas of spatio-temporal borders and perceptual boundaries. she often takes an interdisciplinary approach, working across a range of media, including moving image and sculptural installations, and through collaborative practice. references abram, d. (1997) the spell of the sensuous: perception and language in a more-than-human world. new york: vintage books. barnosky, a. d., matzke, n., tomiya, s., wogan, g. o. u., swartz, b., quental, t. b., … ferrer, e. a. (2011). ‘has the earth’s sixth mass extinction already arrived?’ nature, 471(7336), pp. 51–57. doi: 10.1038/nature09678. buether, a. (2014) ‘the function of colour – an introduction to colour theory and a definition of terms’, colour: design principles, planning strategies, visual communication, buether, a. (ed.) munich: institut für internationale architektur-dokumentation, pp. 7–20. caivano, j. l. 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(2009) ‘finding meaning in art: preferred levels of ambiguity in art appreciation’. quarterly journal of experimental psychology, 62(11), pp. 2105–2112. doi: 10.1080/17470210903038974. morton, t. (2017) ‘timothy morton in conversation with verso books’. youtube. https://www.youtube.com/watch?v=1aey2kmhwh0 (accessed: 15 november 2018). morton, t. (2018a) ‘this is not my beautiful biosphere’, a cultural history of climate change, bristow, t. and ford, t. h. (eds.) london: routledge. morton, t. (2018b) ‘being ecological | timothy morton | rsa replay’. youtube. available at: https://www.youtube.com/watch?v=d_5uwiseve (accessed: 26 march 2019). rose, d. b., dooren, t. v., chrulew, m., cooke, s., kearnes, m. and ogorman, e. (2012) ‘thinking through the environment, unsettling the humanities’. environmental humanities, 1(1), pp. 1–5. doi: 10.1215/22011919-3609940. seligman, a. b. and weller, r. p. (2012) rethinking pluralism: ritual, experience, and ambiguity. new york: oxford university press. steffen, w., crutzen, p. j. and mcneill, j. r. (2007) ‘the anthropocene: are humans now overwhelming the great forces of nature?’ ambio: a journal of the human environment, 36(8), pp. 614–621. doi: 10.1579/0044-7447(2007)36[614:taahno]2.0.co;2. cultura e scienza del colore color culture and science 18 cultura e scienza del colore color culture and science | 02/14 scena, ciò non può che dimostrare la sua importanza. secondo tempo: normalmente si parla di struttura superficiale fine; consideriamola per il momento nella sua massima “finezza” e sempre collegata a un oggetto. negli oggetti artificiali che trovate intorno a voi, anche in questo stesso momento, potete verificare, possibilmente muniti di una lente di ingrandimento, quanto siano rari gli oggetti che presentino una superficie perfettamente priva di tessitura. osservate con la lente un tasto del vostro computer, un laminato plastico apparentemente liscio e altre superfici artificiali; noterete che è sempre presente una tessitura fine. a questi livelli, la struttura superficiale fine viene espressa sotto la denominazione di gloss. questa caratteristica della superficie viene comunemente definita come “brillantezza”, in quanto si tratta di una misurazione che si riferisce a uno standard di riflessione della luce da parte di una lastra di vetro lucido nero, insomma quasi di una superficie specchiante. strumenti detti glossmetri o glossimetri consentono di stabilire, e in che misura, una superficie possa essere considerata lucida o meno lucida oppure opaca. nel momento in cui abbandoniamo questa estrema finezza per passare a considerare “una struttura rilevabile come sistema di elementi simili tra loro” posta sopra alla superficie e facente parte di essa, ecco che ci troviamo di fronte a quella che comunemente chiamiamo texture; la “chiamiamo” perché la rileviamo (detection) considerandola come un unico insieme, quasi un altro “oggetto” (segregazione) e distinguendola dalla superficie della quale fa parte (segmentazione). è facile, per concludere questo “secondo tempo”, rendersi conto che, a prescindere dagli oggetti artificiali (considerate tali, per esempio, anche le pareti interne ed esterne della vostra abitazione), negli oggetti naturali una certa tessitura di superficie è sempre presente. per questa ragione è uno dei succitati elementi per discriminare una scena. arrivati a questo punto avrete certamente compreso che la rilevazione (detection) di una texture è una questione di scala. e se consideriamo, per esempio, di osservare la battigia di una spiaggia sabbiosa che viene solitamente pareggiata dall’andirivieni delle onde, essa ci apparirà come una superficie caratterizzata da una tessitura molto fine, quasi non rilevabile, ma la scena cambierà se ne osserveremo una porzione da circa 50 cm 1. la texture o tessitura vorremmo portare all’attenzione dei progettisti quanto sia frequente “imbattersi” nelle textures, quali siano le loro caratteristiche e le variabili e quanto possa essere interessante prendere in considerazione il loro utilizzo. il fenomeno percettivo delle tessiture è spesso sotto i nostri occhi inconsapevoli e non appena ci si guarda attorno con maggiore attenzione si finisce per accorgersi di quante ce ne siano. nell’affrontare questo tema abbiamo attinto dalla psicofisica le sole basi di partenza. la psicofisica è forse l’unica neuro-scienza che abbia approfondito in modo estremamente puntuale e articolato il tema delle textures. ha affrontato, tra l’altro, gli aspetti di soglia, valutando, con esperimenti di laboratorio su soggetti umani, quali fossero le caratteristiche (features) di una texture affinché si potessero verificare la rilevazione (detection), la segregazione e segmentazione, la rivelazione dei bordi (edges), dove certe caratteristiche di texture finiscono, la rilevazione dei limiti di demarcazione tra una texture e un’altra (boundaries); sono state sperimentate, con severi protocolli scientifici, le capacità di rilevazione di una texture al variare di alcune caratteristiche come la luminanza, il colore, il contrasto, l’orientamento e la densità dei textons (gli elementi componenti di una texture), mentre su macachi veniva verificato quali fossero i neuroni coinvolti nelle diverse fasi di rilevazione. con questo crediamo di aver espresso in modo riduttivo e sicuramente parziale, quanto si è studiato e sperimentato su questo tema. perché questa affascinante branca delle neuroscienze si è occupata (e si occupa) tanto delle textures? proviamo a dare una risposta in due tempi. primo tempo: gli elementi di discriminazione di una scena sono: colore, forma e struttura superficiale (ovviamente deve esserci luce). ciò significa che per essere in grado di comprendere, di dare un senso a ciò che stiamo vedendo in un certo momento (percezione cognitiva), le nostre aree visive discriminano queste tre caratteristiche che possono dare salienza ai diversi elementi della scena (ciò che stiamo osservando), aiutandoci a distinguerli l’uno dall’altro, dunque a valutare lo spazio intorno a noi e la nostra posizione e distanza da ciò che ci circonda. se la struttura superficiale è uno dei tre elementi di discriminazione della giulio bertagna aldo bottoli b&b colordesign, www.bebcolordesign.it tessiture – texture: il fascino delle tessiture apparenti 1902/14 | cultura e scienza del colore color culture and science di distanza, da dove potremo rilevare i granelli che formano la sabbia oppure accorgerci che la sabbia è addirittura formata da piccoli sassolini arrotondati del diametro medio di 2 millimetri. 2. la percezione: definizioni prima di continuare sarà bene però fornire qualche definizione e qualche concetto sulla percezione. innanzi tutto alcune definizioni di texture, così come riportate da lucia ronchi [1 2]. 2.1. texture le definizioni di texture sono molteplici. per esempio, tradotta come “struttura superficiale fine”, viene definita come: • un insieme di elementi geometrici, con una loro distribuzione spaziale, regolare o irregolare, piana o tridimensionale e con determinate caratteristiche salienti (features) che ne inquadrano la configurazione (patterning) con riferimento al processo visivo (orientamento, frequenza spaziale, contrasto, colore, rugosità ecc.); • una variazione continua, connessa allo schema spaziale della superficie; • una caratteristica saliente (feature) che definisce la superficie; una struttura che si contrappone all’uniformità; • una proprietà definita statisticamente (landy e graham, 2003) che impegna sia la visione locale, sia la visione globale; • un’astrazione percepita, l’attributo di un campo con un numero imprecisato di componenti, (non enumerable), ecc.”. 2.2. percezione è nel cervello che hanno luogo quelle complesse sensazioni che chiamiamo “visione delle forme e dei colori”, sensazioni subito elaborate dal nostro atteggiamento nei confronti della situazione, dalla nostra storia, dalla nostra cultura, dalle nostre attese, dalla motivazione e dagli altri nostri sensi congiuntamente, dando luogo alla percezione. la percezione è un’operazione cerebrale mediante la quale la coscienza prende contatto con l’oggetto esterno utilizzando una molteplicità di sensazioni, importante tra le altre, la vista. è definibile percezione l’attività cerebrale nella quale il campo di osservazione viene interpretato cognitivamente, quindi riconosciuto oppure relegato, nell’analisi delle sue componenti di apparenza (forma, colore e struttura superficiale), nella categoria del non conosciuto, dunque del nuovo, dell’appreso. nel momento in cui il cervello trova una spiegazione di ciò che sta vedendo (nell’atto del riconoscimento, della comparazione con il conosciuto o nell’apprendimento del nuovo) si perfeziona l’atto percettivo. 2.3. scena configurazione particolare di forme, luce, colori, tessiture, suoni, odori, temperatura che costituiscano un insieme coerente e caratterizzato e per questo possa essere riconosciuta e distinta da altre, anche avendo subito determinate trasformazioni o variazioni entro una certa soglia. la lettura e l’apprendimento di una scena, seppure fortemente pilotati dalla vista, è un processo polisensoriale. la scena è un elemento percettivo di riconoscibilità dell’ambiente, quindi di orientamento. in psicofisica per scena si intende ciò che rientra nel campo di osservazione visiva; il termine è finalizzato all’analisi delle sue componenti e delle sue variabili (forme, colori, strutture superficiali, illuminazione, ecc.) al fine di stabilire le reazioni psicologiche e fisiologiche degli osservatori determinando in tale modo valori di soglia, tempi di reazione agli stimoli, comportamenti, neuroni e aree cerebrali coinvolte nei diversi stadi percettivi, ecc.. 2.4. segregazione e segmentazione le operazioni di segregazione e segmentazione sono alla base dei meccanismi di comprensione di ciò che osserviamo. in linea di massima, la segregazione è l’individuazione di una forma compiuta o l’individuazione di più punti o elementi in coerenza tale da poter costituire un insieme. la segmentazione è il conseguente atto di raggruppamento in un insieme e la discriminazione dello stesso dagli altri elementi della scena che, a quel punto, andranno a far parte dello sfondo o di un certo altro piano di profondità. 3. l’evoluazione della visione e della percezione; caratteristiche percettive delle scene naturali l’ambiente naturale ha avuto un ruolo fondamentale per lo sviluppo delle capacità visive e percettive. l’essere umano è stato in grado di sopravvivere proprio grazie all’atto percettivo. il saper riconoscere in tempo situazioni potenzialmente pericolose o portatrici di vantaggi ha affinato la capacità percettiva dei nostri progenitori. questa capacità, necessaria e vitale, si è sviluppata grazie al processo di adattività all’ambiente naturale. “è convinzione della scienza che gli organismi viventi, nella loro evoluzione, abbiano sviluppato processi e strategie biologiche 20 cultura e scienza del colore color culture and science | 02/14 strettamente associate al loro ambiente (l. ronchi cita corth, 1983) e che le caratteristiche dell’ambiente influiscano sulla struttura neuronale del sistema visivo“ (l. ronchi cita rudermann, 1997). lucia ronchi, sempre citando corth, sottolinea che “per svariati milioni di anni i primati sono stati esposti alla luce diurna filtrata dalla vegetazione delle foreste; questa luce ha una distribuzione spettrale che presenta un massimo a 550 nm, proprio in corrispondenza del massimo della curva di efficienza visiva”. 4. caratteristiche percettive delle scene naturali 4.1. premessa sulla percezione di una scena anche i ricercatori nel campo della psicofisica asseriscono che la percezione di una scena è assai diversa se il soggetto vi si trova all’interno realmente oppure se la osserva in una rappresentazione o fotografia. tutti coloro che fanno progetto sanno bene la differenza sostanziale tra la valutazione di un ambiente renderizzato seppure in modo sorprendentemente “fotografico” e quella che si fa quando ci si trova all’interno di un ambiente. per noi esseri umani è imprescindibile, per una corretta valutazione percettiva, essere consapevoli dello spazio nel quale ci stiamo muovendo e sentire la nostra corporeità (propriocezione) in relazione con l’intorno, con gli oggetti, con le persone con le quali ci relazioniamo. le textures vanno “scoperte” nella loro effettiva residenza, nella loro genesi data dalla nostra posizione e distanza rispetto ai loro componenti, soprattutto se si tratta di textures apparenti. l’atto percettivo è polisensoriale, occorre perciò “trovarsi sul posto” e nel caso di un oggetto, “toccare con mano”. 4.2. quinte di profonditá si può notare che in un campo di osservazione i diversi elementi si configurano come appartenenti a diverse quinte. possiamo definire quinta di profondità il luogo di diversi elementi della scena posti a una medesima distanza media dal punto di osservazione in cui ci troviamo. le quinte di profondità ci forniscono l’informazione necessaria per renderci conto della nostra posizione all’interno del contesto ambientale. il nostro spostarci all’interno del contesto nel quale ci troviamo, porterà variazioni coerenti nella configurazione delle quinte di profondità. queste variazioni di configurazione saranno alla base del nostro apprendimento del contesto, fornendoci la capacità di riconoscere il luogo e di orientarci. 4.3. gradiente di tessitura una caratteristica dell’ambiente naturale è quella di apparirci sempre come un insieme di elementi e superfici dotate di una certa tessitura. data una certa tessitura considerabile mediamente omogenea (per esempio un prato), uno degli indizi che ci aiutano a intuire la distanza tra noi e un qualsiasi elemento della scena è l’addensarsi della tessitura contemporaneamente all’apparente “ridursi” degli elementi che la compongono. possiamo chiamare questa compressione apparente che aumenta con la distanza come gradiente di tessitura. 4.4. gradiente di salienza, di tinta, di sfumatura, di luminanza salva una rarissima monotonia in natura e una altrettanta difficile nell’ambiente artificiale, ogni scena ha uno o più punti cospicui, più in risalto rispetto agli altri, che potremo quindi definire salienti; elementi che il cervello prenderà in maggiore considerazione, in quanto di notevole ausilio per l’apprendimento del luogo e, di conseguenza, per l’orientamento e la riconoscibilità in occasioni successive. le diverse distanze tra gli elementi salienti e le caratteristiche degli stessi sono alla base della lettura e comprensione della configurazione di una scena. si parla di gradiente di salienza in quanto questa si modifica coerentemente a seconda dei nostri spostamenti all’interno del luogo. le caratteristiche di tinta, sfumatura e luminanza degli elementi di una scena sono spesso dipendenti dalla loro distanza dall’osservatore. 4.5. permeabilitá percettiva le piccole porzioni che una quinta lascia intravedere della quinta che nasconde ci forniscono una certa possibilità di previsione e di ricostruzione percettiva della parte di quinta nascosta grazie al completamento amodale. questa nostra capacità di ricostruire e riconoscere non utilizzando uno o più sensi (da qui amodale), ma con l’immaginazione alimentata dall’esperienza ciò che è in varie sue porzioni nascosto da uno o più ostacoli visivi è un’attività percettiva innata. a seguito di ciò possiamo asserire che questa nostra capacità si sia sviluppata e adattata alla configurazione tipica dell’ambiente naturale boscoso che potremmo definire permeabilità percettiva; lo sguardo può penetrare in parte e l’immaginazione farà il resto. 4.6. profonditá breve una tradizionale soluzione per eliminare il senso 2102/14 | cultura e scienza del colore color culture and science di oppressione di un muro di cinta di un cortile è di farlo ricoprire da una pianta rampicante. l’impermeabilità percettiva del muro viene quasi annullata; lo spessore del fogliame della pianta rampicante (si tratta comunque di una texture naturale) e gli effetti chiaroscurali che creano le sue foglie ci danno l’illusione di una certa permeabilità percettiva. questo suggerisce al nostro sistema percettivo l’attivazione del completamento amodale seppure in assenza degli stimoli visivi necessari, cioè di qualche porzione visibile al di là delle foglie del rampicante. il confinamento nei confronti di tutto ciò che sta al di là di quel muro apparirà più accettabile, meno invalicabile, meno oppressivo. la profondità breve può trasformare un muro invalicabile in un bosco accessibile e infinito. i progettisti in architettura d’interni sanno bene quanta profondità possa dare a un ambiente anche piccolo uno scaffale pieno di libri e oggetti; i suoi trenta centimetri circa di capienza hanno la caratteristica percettiva della profondità breve. in linea di massima una parete con una certa tessitura risulta più accettabile di una parete assolutamente uniforme; questo farebbe pensare che un muro rifinito a rinzaffo risulti più gradevole di uno ad arenino fine. possiamo ipotizzare che una certa attivazione del completamento amodale si attivi anche quando la profondità breve si riduce, così che una superficie, verticale oppure orizzontale che sia, ci appaia dotata di una certa permeabilità e di una tessitura fine tale da ridurne l’aspetto di artificialità, avvicinandone la percettibilità a quella degli elementi naturali. profondità breve può essere dunque la definizione di quella sensazione di permeabilità percettiva (anche se non sussistente) fornitaci da un certo rapporto chiaroscurale di una texture su scala adeguata. 5. caratteristiche percettive della texture l’individuazione e la valutazione della tessitura di una superficie non può prescindere dalla distanza di osservazione; al variare della distanza di osservazione interverrebbero molte variabili di rilevazione e valutazione, rendendo priva di significato qualsiasi categorizzazione. basti pensare, per esempio, alla tessitura costituita dagli steli d’erba di un prato; in una osservazione ravvicinata la tessitura si presenterebbe non fine, impura, disordinata e disomogenea, ma avremmo probabilmente consapevolezza del fatto che si tratti di una tessitura naturale, mentre un prato osservato da una certa distanza ci farebbe valutare la tessitura come fine, ordinata e omogenea. 5.1. distanza di rilevazione e di valutazione si conviene perciò che le valutazioni di una tessitura debbano avvenire in condizioni di osservazione di prossimità e, come si fa per valutare correttamente il colore di una superficie, per mezzo di un isolatore da traguardo, quindi in modo apertura. 5.2. modi di presentazione di una texture (ricavati-dedotti dai modi di presentazione del colore) 1) texture oggetto la texture oggetto è vista e valutata in quanto appartenente all’oggetto stesso; difficile quindi fare astrazione da valutazioni emancipate dai significati e dalle caratteristiche dell’oggetto stesso. da considerare che un oggetto, solitamente, viene visto non isolato, ma inserito in un contesto che ne determinerà, su quella specifica scala di osservazione, certe varianti visivo-cromatiche ed effetti percettivi. 2) texture superficie la tessitura superficiale è quella vista e valutata concentrando l’osservazione su di una porzione della superficie dell’oggetto ovvero nel tentativo di astrazione cognitiva dell’oggetto in quanto tale; entrano in gioco però alcune caratteristiche variabili della superficie come trasparenze, colore, lucentezza e poi illuminazione, ombre, eccetera. 3) texture apertura probabilmente la modalità più corretta e neutra ovvero emancipata dalle variabili anzidette. la texture è visibile e valutabile isolando una piccola porzione della superficie dell’oggetto attraverso un foro praticato in uno schermo di cartoncino (isolatore); l’oggetto o la superficie dovranno essere a opportuna distanza dall’isolatore. per quanto riguarda invece la valutazione di una texture, mettere a fuoco sui bordi del foro significherebbe mettere la texture fuori fuoco. il fuoco ottico deve andare sulla texture, ma questo metterà a disagio perché, in visione binoculare, il foro tenderà a “duplicarsi”. bisognerà dunque traguardare con un solo occhio. 5.3. distanza di osservazione per quanto riguarda la determinazione di quale sia la distanza di osservazione così detta “di prossimità”, dobbiamo considerare due diverse situazioni di relazione tra un osservatore e una superficie che abbia caratteristiche di tessitura. 5.4. texture nella scena la prima situazione da considerare è che la superficie appartenga all’ambiente nel quale l’osservatore si trova e vada quindi a costituire un elemento dello scenario. che si tratti di una 22 cultura e scienza del colore color culture and science | 02/14 superficie orizzontale, inclinata o verticale, si può convenire che la distanza di prossimità sia in media di circa 160 cm-300 cm. 5.5. texture nell’oggetto la seconda situazione è che la superficie con caratteristiche di tessitura appartenga a un oggetto di dimensioni e peso tali da poter essere impugnato e brandeggiato agevolmente dall’osservatore. la valutazione della tessitura avverrà a una distanza media di circa 40 cm. bisogna considerare però che qualsiasi aggregato di elementi simili, anche in condizioni di disomogeneità, pur avendo i singoli elementi grandi dimensioni, se osservato da una distanza sufficiente, può apparire come una tessitura. 6. le macro-categorie delle textures: tessiture intrinseche e le tessiture apparenti le tessiture intrinseche sono quelle rilevabili in osservazione prossimale come effettive strutture superficiali fini. possiamo ritenerle quindi caratteristiche fisiche proprie della superficie siano esse strutturali, applicate (per es. pittura, stampa) oppure ricavate (per es. fresature, goffrature, ecc), anche se per queste ultime l’aggettivazione “fini” può risultare compromessa. le tessiture apparenti sono invece quelle formate da un aggregato di elementi con determinate similarità tra loro e con una certa densità tali da apparire come una texture. la particolare ricchezza di segnale visivo di una texture apparente è che, nella maggior parte dei casi, è formata da elementi a loro volta caratterizzati da una tessitura intrinseca. risulta immediata una sostanziale differenza tra le due che riguarda la rilevazione, ovvero la possibilità per l’osservatore di attuare segregazione e segmentazione. la rilevazione delle tessiture intrinseche è solo questione di opportuna distanza di osservazione, cioè sono sempre tessiture superficiali fini anche quando ci appaiono come superfici perfettamente uniformi perché magari le osserviamo da una distanza eccessiva. la rilevazione delle tessiture apparenti è anch’essa questione di distanza e di prospettiva di osservazione, ma è di carattere fortemente percettivo. le textures apparenti, infatti, non hanno valori intrinseci di superficie, in quanto si tratta di aggregazioni di singoli elementi simili, dunque “esistono” solamente se il punto di osservazione e la distanza sono favorevoli e se la “superficie coinvolta” è sufficientemente vasta per essere rilevata e “isolata” dal resto della scena come texture. questa è l’ultima delle possibili definizioni di texture (che ho riportato più sopra), forse quella che si addice meglio alle tessiture apparenti soprattutto nell’essere definita come “astrazione percepita”. a questo punto risulterà subito chiaro che se è vero che nel naturale e nell’artificiale la tessitura intrinseca è una caratteristica comune “delle cose” più che un’opzione possibile, è anche vero che le tessiture apparenti sono un mondo vastissimo di opportunità percettive e che forse sono più affascinanti delle prime per le loro genesi, per la loro cangianza percettiva e soprattutto perché formate da elementi, la superficie dei quali è probabilmente già caratterizzata da una propria tessitura fine intrinseca resa non rilevabile dalla distanza. le textures apparenti sono quindi tessiture che contengono altre tessiture. il loro fascino, che fa soffermare lo sguardo e l’interesse e che desta certe emozioni, è la loro ricchezza di segnale caratterizzato da una coerenza tale da non apparirci come “rumore visivo”, ma come “indispensabile percepito” per comprendere e apprezzare ciò che ci circonda. un’altra caratteristica percettiva comune tra textures e colore è la loro “invisibilità percettiva”. ne siamo tanto avvolti e siamo tanto abituati a queste due caratteristiche con le quali percepiamo il mondo esterno da non esserne consapevoli coscientemente. però c’è una differenza; mentre una certa dominante cromatica, un certo colore inconsueto ci scuote, ci emoziona e ci porta a riferire l’esperienza (...il cielo era rosso fuoco...) una certa tessitura apparente, pur provocando in noi gli stessi effetti non viene riferita come texture, ma citando i suoi componenti aggregati (...a terra c’era una moltitudine di foglie secche dai caldi colori autunnali...), oppure con denominazioni specifiche (pavimento in seminato alla genovese, piastrellatura, tessuto a pois, parquet, truciolare di legno, spiaggia di ciottoli, maglia di lana, campo di frumento, tetto in lastre di ardesia, ecc). eppure nessuno di questi “oggetti” sarebbe riconoscibile e categorizzabile se non fosse identificato nel suo essere una texture; perché di texture si tratta e di textures apparenti come la stessa colonna di testo che state leggendo. 7. “neurofisiologia” della texture ci rendiamo conto dell’azzardo nel titolo di questo capitolo, crediamo tuttavia che possa sintetizzare la concisa ed elementare analisi delle implicazioni neurofisiologiche nella percezione delle textures che intendiamo proporre. questo premesso, iniziamo a considerare ciò che deve elaborare il cervello per “vedere” un oggetto singolo. 2302/14 | cultura e scienza del colore color culture and science i primi dati arrivano dagli occhi, dalle rètine dove i coni, in visione diurna (fotòpica), si attivano in misura maggiore o minore a seconda della luminosità di una certa lunghezza d’onda della luce emessa dall’oggetto illuminato. questi dati, forniti dai coni, vengono trasmessi ed elaborati da altre cellule visive della rètina (cellule orizzontali, bipolari, amacrine e gangliari...) e inviati ai nuclei genicolati laterali attraverso gli assoni delle cellule gangliari (nervo ottico). qui la mappatura dell’immagine viene ancora analizzata da altre cellule e trasmessa alla corteccia visiva primaria (v1 e v2) dove si trovano molti tipi diversi di cellule specializzate per l’orientazione, che si attivano se riconoscono, nella configurazione fornita, angoli, curve, linee inclinate secondo certe angolazioni, fino a poter definire i bordi che delineano l’oggetto (pensiamo che questo oggetto sia la foglia di un albero). altre di queste cellule specializzate sono in grado di attivarsi segnalando l’eventuale movimento delle singole parti dell’oggetto e la direzione dello spostamento. questi dati vengono poi elaborati da altre cellule che definiscono meglio le forme individuate (cellule non-blob) e, contemporaneamente, da altre ancora (cellule blob) che forniscono diverse sensazioni a seconda della lunghezza d’onda dominante delle superfici interne ai bordi individuati dell’oggetto (colore o sensazione cromatica). i dati convergono (area visiva v4) ed ecco che “vediamo” l’oggetto (la foglia in questione). il cervello svolge quindi un lavoro impressionante per renderci visibile una foglia, rendercela riconoscibile anche se si muove e attribuirle una serie di colori. basterà dunque immaginare il lavoro del cervello per renderci capaci di ammirare la chioma di una grande quercia al vento, foglia su foglia, ramo su ramo, per considerare quella cerebrale un’attività mostruosa. ma non è finita. infatti, mentre osserviamo la grande quercia, non solo il cervello gestisce anche le nostre funzioni vitali (frequenza cardiaca, pressione arteriosa, respirazione adeguate alle circostanze, ecc.) e fa in modo che si mantenga l’equilibrio, ma elabora continuamente la nostra posizione in quello spazio, le condizioni del suolo, gli ostacoli in vicinanza, gli eventuali pericoli in avvicinamento. e non è tutto qui perché, con molta probabilità, sta facendo bilanci, sta programmando cosa fare, cosa dire, come comportarsi quando qualcun altro ci parla, in una sequenza di ipotesi e contro-ipotesi estremamente complesse, che richiamano avvenimenti memorizzati, evocano i suoni di voci conosciute, fanno nascere emozioni. eppure, dopo la passeggiata, ci sentiamo più sereni, rilassati e non certo perché il verde è riposante! come già detto, gli esseri umani hanno sviluppato le loro capacità visive e percettive all’interno di ambienti naturali boscosi. dunque se si accetta di definire come texture apparente la chioma di un albero frondoso, ne consegue il considerare l’ambiente naturale come caratterizzato dalle textures, sia intrinseche che apparenti, e la nostra conseguente adattività (adeguamenti neurofisiologici) alla visione e percezione delle stesse. sedersi davanti a una parete rivestita di laminato plastico di un unico colore e osservarla per alcuni minuti, farebbe sentire chiunque a disagio. il cervello, da un punto di vista visivo, più che riposarsi, subirebbe un certo stress da deprivazione di stimoli e per il continuo lavoro di fotorecettori dello stesso tipo (sensibile alla lunghezza d’onda del colore della parete). se la parete fosse di colore bianco? qualcuno potrebbe affrettarsi a chiedere. ancora peggio, risponderemmo, i coni retinici stressati sarebbero proprio tutti. il cervello, a quella visione di “campo vuoto” ci porterebbe all’introspezione oppure all’addormentamento con il forte disagio di chi si rende conto di trovarsi “confinato” come in cella. il cervello si riposa con il cambiamento. la natura cambia sempre intorno a noi e anche noi siamo in costante cambiamento (crescita e invecchiamento); il cambiamento è un fattore biologico, ineluttabile e in molti casi per noi necessario per il benessere. 8. categorizzazioni delle texture apparenti nel momento in cui ci si propone di affrontare un tema percettivo, dunque caratterizzato da una componente psicologica, è quasi inevitabile cercare di “organizzare” il sistema tematico in categorie o tipi. lo scopo non è quello di imporre una schematizzazione da introiettare, ma di analizzare le possibili varianti del sistema per rendersi consapevoli delle stesse, individuando così una piattaforma cognitiva utile per il progetto. una texture è caratterizzata dai suoi componenti, i textons, le possibili varianti dei quali determineranno le diverse categorie delle tessiture. le variabili dei textons sono: tipologia, forma, dimensione, colore, aggregazione, orientamento, densità e altre; le variabili hanno un limite numerico difficile da determinare; anche in psicofisica si usa “ecc.”. 8.1. texture apparenti / genesi naturali spontanee: quando offerte dal mondo naturale senza alcun apporto dell’uomo (chioma frondosa di albero, prato polifito misto, spiaggia sabbiosa, ecc.) naturali antropizzate: quando offerte dal 24 cultura e scienza del colore color culture and science | 02/14 figura 1 artificiale strutturale/funzionale pura non ordinata omogenea figura 2 naturale spontanea pura non ordinata non omogenea figura 3 artificiale strutturale/funzionale pura non ordinata omogenea 2502/14 | cultura e scienza del colore color culture and science figura 4 naturale antropizzata pura non ordinata non omogenea figura 5 artificiale decorativa pura non ordinata non omogenea figura 6 naturale spontanea pura non ordinata omogenea 26 cultura e scienza del colore color culture and science | 02/14 mondo naturale manipolato dall’uomo (lastre di marmo, di pietra, tavole di legno, ecc.) artificiali decorative: se applicate secondo un modulo ripetibile, questo è il “rapporto”; un buon rapporto è tale quando le dimensioni del modulo e l’aggancio visivo di continuità della tessitura sono meno discriminabili (pavimento in seminato di marmo, piastrelle ceramiche, parquet di legno, decorazioni stencil, spatolati, spu-gnati, stoffe a pois, a losanghe, ecc.) artificiali strutturali/funzionali: quando risultanti da particolari strutture realizzate per finalità non decorative, ma di sostegno o costruttive oppure quando create per rispondere funzionalmente a specifiche necessità (stoffa, muro di mattoni, muro di pietre a secco, tralicci metallici, ecc.), (impugnature, superfici goffrate anti-sdrucciolo, ecc.) artificiali percettive: se risultanti dall’aggregazione visiva, quando resa possibile, di elementi, strutture, manu-fatti similari in special modo se osservate da lontano (colonnati, colline terrazzate per coltivazioni, pennelli frangiflutti realizzati con massi o elementi specifici, oggetti della stessa tipologia aggregabili percettivamente da un certo punto visuale, ecc.). 8.2. caratteristiche delle textures pure: quando i componenti appartengono alla stessa tipologia. non pure: quando i componenti sono di tipologie differenti. ordinate: quando i componenti sono allogati secondo un ordine, densità media e orientamento discriminabili. non ordinate: quando i componenti sono allogati secondo nessun ordine, densità media e orientamento discriminabili. omogenee: quando i componenti sono uguali o molto simili per almeno due caratteristiche tra: forma, dimensione, colore. non omogenee: quando i componenti sono uguali o molto simili ma per una sola caratteristica tra: forma, dimensione, colore. bibliografia [1] lucia r. ronchi, “la scienza della visione dal punto di vista delle scene naturali”, fondazione giorgio ronchi, firenze 2006. [2] lucia r. ronchi-s.villani,”l’interazione uomo-ambiente alle soglie del 2000”,mariposa editrice, fornacette (pi) 1998. [3] giulio bertagna-aldo bottoli, “perception design, contributi al progetto percettivo e concetti di scienza del colore”, maggioli editore, santarcangelo di romagna (rn) 2009. [4] giulio bertagna-aldo bottoli, “scienza del colore per il design”, maggioli editore, santarcangelo di romagna (rn) 2013. figura 7 artificiale strutturale/funzionale pura ordinata omogenea 24 color culture and science journal vol. 13 (1) doi: 10.23738/ccsj.130103 the selection of colors for fashion collections in relation to color theory: a case study from the analysis of brazilian ready-to-wear gisela costa pinheiro monteiro 1 , camila assis peres silva 2 1 universidade federal fluminense, niterói, brasil, giselamonteiro@id.uff.br 2 universidade federal de campina grande, campina grande, brasil. camiaps@gmail.com corresponding author: gisela monteiro (gisela.gisdesign@gmail.com) abstract this paper is a brazilian case study that will demonstrate the relevance of the color chart in fashion management. in general, clothing creation companies usually select several specific colors to use in order to assist not only the creative process, but also to guide the purchase of inputs such as fabrics and trims for each collection. it is worth saying that the colored samples of these colors are organized on a sheet of paper and each one receives an identification. that said, the purpose of this paper is to analyze the way in which companies arrange colors on the chart in order to check if there is any relationship with the color theory in this process. keywords color chart, fashion design, brazil, color theory. received 25/01/2021; revised 18/03/2021; accepted 28/03/2021 the selection of colors for fashion collections in relation to color theory: a case study from the analysis of brazilian ready-to-wear 25 color culture and science journal vol. 13 (1) doi: 10.23738/ccsj.130103 1. introduction “fashion” is a cultural phenomenon that refers to the cyclical change of society in relation to language, manners, ideas, tastes, habits, choices and affects artifacts in general, such as furniture, cars, home appliances and decorative objects (calanca, 2008, p. 11; lipovetsky, 1989, p. 24). usually, fashion is applied to all social arenas and clothing is one of the cases (simmel, 2008). although its meaning is not limited to clothing, in this research the word “fashion” will be used about clothing. and, more specifically, the creation of clothing items, which is one of the moments when color is of fundamental importance. after all, it is a striking feature in any piece of clothing: a yellow shirt, green pants, a white dress. that is, the pregnant color in the pieces is very noticeable to the public, but few notice the color of the sewing thread, the color of the zipper, the bias, the collar, the label. the garment is accurately designed by fashion designers at the time of creation. in addition, it is possible to see in store windows that the pieces were designed to generate a series of combinations, such as the mathematical “combinatorial analysis”. designers plan the 'mix and match' among the pieces. in these cases, the challenge is to use the same color in fabrics and materials with different lightness, textures, trim, such as jeans and cotton t-shirt. there is a margin of acceptance due to the difference in materials, but there needs to be a balance. that is why, before starting to design a clothing collection, designers select the colors they want to use and organize them in a chart called a color chart. it will serve as a source of consultation for the team from before creation to production, considering all moments of the design process. the experience in higher education in fashion design has shown the challenge students have to deal when applying colors in their final projects. there is still a gap between theory of color teaching and the way colors are presented in fashion trend catalogs, that designers frequently use as reference. pantone® colors are present in the daily life of this student and young professional. in an attempt to narrow the dialogue between the use of pantone colors and a theoretical basis, we began to analyze the organization and composition of the color charts of the collections, starting with four companies that we present in this paper as case of study. 2. color and fashion design: how theory is used by designers as previously mentioned, color is relevant in the fashion world and the color chart plays a fundamental role in this environment. the color chart is a showcase that gathers samples of colors used in the collection. the selected colors will guide the creation during a project and the purchase of inputs for the manufacture of garments. it is necessary to make clear the need to describe colors accurately to avoid miscommunications. thus, each color sample, that is, one “small solid printed square (plated), is accompanied by a technical reference provided by a paint manufacturer” [1] (bann, 2012, p. 193). these references are codes that will allow those involved with the project to use exactly the desired colors, even without looking at the samples. regarding the fashion universe, these colors reference used to create the color charts are usually consulted in color catalogs manufactured by pantone®. which is an international company recognized for selling printed and bound color guides with the purpose of allowing “designers to ‘colour match’ specific colours when a design enters production stage regardless of the equipment used to produce the colour” (design face, 2020). thus, there is greater control on the part of creation. it can be said that pantone® conquered the market thanks to the style consultancy offices, which from 1965 began to establish guidelines to facilitate the production flow, reducing the insecurity of industrialists in the face of the need to periodically reinvent themselves at each cycle. after all, a collection is nothing more than a landmark of ephemerality, as it reinforces the obsolescence of the old collection, as soon as the new one comes into force (liger, 2012, p. 19). which means that periodically these offices have had to develop new color combinations for their new collections. in practice, according to françoise vincent-ricard one of the pioneers at the head of the french office promostyl the work of such offices has consisted of researching and providing companies with information on trends in the form of illustrated notebooks (1989, p. 58). the information offered in those notebooks was categorized in “style” indications about colors, shapes and materials related to the textile process for the industrial fashion chain, from spinning to retail (rech, 2006). promostyl, as well as the french carlin and the brazilian inova moda, provides pantone’s reference when citing the colors of the season. since 1963, pantone®, under the command of lawrence herbert, has developed color matching systems for a variety of substrates, including fabric (design face, 2020). from this brief explanation we aim to present the close relationship between style consultancy offices and the pantone® color system. not only that, we would say that colors for fashion designers has been synonymous with pantone. regarding its application in the fashion market, the company presents the pantone® textile color system which is separated in two sort of color charts the colors the selection of colors for fashion collections in relation to color theory: a case study from the analysis of brazilian ready-to-wear 26 color culture and science journal vol. 13 (1) doi: 10.23738/ccsj.130103 references in dyed cotton (tc or tcx) and the colors references printed on paper (tp or tpx). “the suffix ‘tp’ stands for ‘textile paper’ and the suffix ‘tc’ stands for ‘textile cotton’” (pantone, 2020a). the addition of letter x means that the colors belong to an extended range. as well as it is a code to differentiate the most recent editions. another suffix can be found on pantone® textile color system, launched in 2015, the eco-friendly formulations which are printed on paper is represented by tpg, which stands for textile paper green (pantone, 2015). finally, we understand that pantone® is a reference widely used in the field of fashion design due to its presence throughout the ‘design process’ (design council, 2020). since from the discovery phase (insight into the problem), when designers consult trend books developed by companies such as carlin, until the deliver phase (the solution that work) once that pantone® color guides are easily available both digitally and physically in the hands of the professionals of supply chain. what, therefore, enables communication between creation and a product? from this, we can infer that the relationship of designers with the theory of cuts tends to be influenced by the nomenclatures and organization of colors that this company uses. 3. pantone textile system notation: the theory unknown or neglected by designers pantone textile system notation is based on a cylindrical solid and consists of a code of three pairs of digits. the first two digits of the pantone code show the lightness (value) of the sample on a scale ranging from 10 (lightest, 90% to 100% reflectance) to 19 (darkest, 0% to 10% reflectance). the second pair of digits shows the hue of the sample and it consists of the section of the cylinder a tone circle. this tone circle is divided into 64 sectors, starting with 01 for yellowish green, and ending in 64 for greenish yellow. the third pair shows the sample chroma on a scale from 00 for gray to 64, the maximum saturation assumed (fig. 1). this system for color numbering, although not explicit on the company’s website 2 , demonstrates its relationship to the theoretical foundation considering the three attributes of color as in the munsell system (régula, 2004; araújo, 1991). in which concerns to color samples presentation in pantone color guide, there is no explanation in the company website about the criteria used to organize them. so as to take the discussion to the field of theory of colors, we suggest that pantone has been mainly organizing its colors by considering the attributes of hue and value. fig. 1. pantone textile system notation (hirschler, 2002 apud régula, 2004). differently from munsell book of color, in which each sheet (page) has two axes of coordinates (vertical for value and horizontal for chroma), pantone presents in each sheet its colors in one single vertical axis (fig. 2). each one of these sheets presents one hue which varies in value and chroma. despite of that, it is not easy to identify the variation of chroma. the perception of lightness is more obvious. even though there is no logical precision in the ordering of color attributes, pantone color guide allows the user a wide view of all hues when opening the book in the form of a 'quarter circle'. as we can see in the following figures. fig. 2. pantone color guide and the munsell book of color (pantone, 2020). 4. design process: how fashion designers use color the knowledge of colors has wide influence on design process. not only the selection of color samples, but not only that, the knowledge of its attributes, its semantic aspects and the possibility of chromatic combinations are of great relevance in this process. considering the four phases of the design process based on the double the selection of colors for fashion collections in relation to color theory: a case study from the analysis of brazilian ready-to-wear 27 color culture and science journal vol. 13 (1) doi: 10.23738/ccsj.130103 diamond (design council, 2020), we can identify the role of color in each one of them. the designer starts his process with the trend research (1. discover), where the color references will be analyzed especially under the meaning aspect. in the next phase (2. define), from the elaboration of a semantic panel to conceptualize the collection, the designer will extract the colors to assemble the charts. it is important to register the color codes and search for equivalences in the pantone catalog that serves as a reference to facilitate communication between designers and suppliers. in the third phase (3. develop), the designers elaborate the collection and at that moment two questions are important. the first question is the search for color equivalence among the different materials used in garment (which evolves color applied to fabrics, metals, plastic, etc.) to maintain an acceptable harmony. the second question is how designers will organize the colors in terms of color balance (analogous and complementary, for example), contrast (hue, value and chroma) and in terms of chromatic proportion. all this care with the use of colors is due to the possibilities of interaction inherent to them, as postulated by albers. and that will consequently affect the visual perception of the target audience. finally, in the fourth phase (4. delivery), the designer must provide the solution that works. that it is, regarding the use of colors, what is feasible to make the colors that best applies to the various items of garment. keeping in mind the need evaluates the selection of pigments to minimize the possibilities of metamerism. as well as providing a technical sheet with the largest possible number of equivalent references. in the case of fashion designers, it is common to specify pantone. this reference serves as base to compare with other color catalogs of supply chain. 5. case of study: brazilian color charts 5.1. methods and materials to carry out a case study of the trendy color chart, we selected color charts from the same year and the same season (winter) of four similar companies were analyzed. it was done based in the fact that: 1) they are companies located in the state of rio de janeiro, brazil (in which place the research were taken); 2) hire fashion designers on their staff; and 3) serve the young female audience. in order to facilitate observation and maintain the confidentiality of companies, the collected cards were redesigned, however, maintaining the same order and number of colors per line with their respective references (color name and color catalog reference), exactly as the original ones. in this paper we will refer to these companies as brand 1 (b1), brand 2 (b2), brand 3 (b3) and brand 4 (b4). we present next a miniature version of these color charts indicating the numbers of each color used by each brand. these numbers preceded by hashtag are also used in the analysis boards present further. the aim is allowing an analysis of these color organization in each brand’s color charts. note that b1 and b2 (fig. 3) presents one single group of colors meanwhile b3 and b4 (fig. 4) presents more than 1 group of combinations in which some colors are repeated. fig. 3. miniature version of color charts from brand 1 and brand 2. the selection of colors for fashion collections in relation to color theory: a case study from the analysis of brazilian ready-to-wear 28 color culture and science journal vol. 13 (1) doi: 10.23738/ccsj.130103 fig. 4. miniature version of color charts from brand 3 and brand 4. it is worth mentioning that all companies use the pantone textile reference. brands 1, 2 and 3 use pantone tpx on their cards and brand 4 uses tcx. such references were used to assist the authors in reorganizing the color charts of each one of the brands into analysis boards. the elaboration of such boards aims to allow an analysis of how brands take advantages color attributes variations hue and value. in these analysis boards, different from how companies present in their color charts, we order colors by these two attributes. as pantone itself does, such brands selected for this research also name their colors, as it is easier to identify than to call them by code. these names, which we will refer to here as trade names, are somehow related to the vocabulary of the target audience and to the concepts that the brand wants to communicate. we can notice three forms of nomenclature in the color charts: (1) hue name; (2) hue name + commercial name; and (3) commercial name. in this analysis we are also interested in highlighting which names are related to each of the colors. to do this we will keep the original names and translate them into english when necessary. 5.2 analysis and discussions when carefully analyzing the organization of colors in the charts developed by the brands studied in this paper, we observe a logic of visual organization by value (lightness) and/or hues in b1, b2 and b3. however, we chose to do a more detailed analysis considering that the first pair of digits correspond to value, and the second pair of digits correspond to hue. by checking the analysis board 1 (fig. 5), we can observe that all the brands use light, mid and dark tones. looking to the # color numbers, we can see that, excepted by b1, there is no logical sequence when considering lightness assortment. the same thing happens when we observe the analysis board 2 (fig. 6), there is no logical sequence when considering hue assortment. concerning to color naming, we can notice that b3 and b4 have four colors with the same codes, but with different names. this is proof that each brand names its color according to its collection. there also the use of the same name (sand) for light tone colors (b1 and b4). in general, considering that the color references used by the designers of the four brands analyzed come from the same source, from the major trend companies, it is admissible that such colors are similar if not the same. in this case, the names of the colors play an important role in the conceptualization of the collection. these names bring an atmosphere that can relate to varied stories. creating them is one of the possible storytelling techniques, a resource that the designer can use to convey the desired atmosphere (lidwell, holden, butler, 2003, p. 230). for example, the colors of b4 are: sand; yellow africa; night blue; orange bossa nova; atlantic green; kilim pink; and black. we could deduce that the theme presented is brazilian culture with the influence of africa. making the person feels like being in a mystery night to the sound of bossa nova on the sands of an atlantic ocean beach. this just to illustrate how colors and names can be related to contribute in the creative process and marketing strategies. the selection of colors for fashion collections in relation to color theory: a case study from the analysis of brazilian ready-to-wear 29 color culture and science journal vol. 13 (1) doi: 10.23738/ccsj.130103 fig. 5. detailed analysis by value. the selection of colors for fashion collections in relation to color theory: a case study from the analysis of brazilian ready-to-wear 30 color culture and science journal vol. 13 (1) doi: 10.23738/ccsj.130103 fig. 6. detailed analysis by hue. the selection of colors for fashion collections in relation to color theory: a case study from the analysis of brazilian ready-to-wear 31 color culture and science journal vol. 13 (1) doi: 10.23738/ccsj.130103 6. conclusion results shown us three important things concerning to: color naming, color organization and color harmonies. regarding the identification of colors on the charts, in addition to the pantone code, a commercial name is used. it usually comes preceded by the name of the color plus its characteristic, such as “pink kilim”, referring to the shade of pink commonly used in indian tapestry. alternatively, the name used alludes to a known color, such as “scarlet” which refers to scarlet red. in this analysis, we could observe the repetition of the same color in different cards only with the change of the commercial name. as for the organization, we identified that three of the four companies organize colors according to the hue (following the sequence of colors in the spectrum) and the fourth organize them by the color harmonies. finally, as for the color combinations, we could find that companies would better take advantage of it if they had considered dimensions of color such as hue, value and chroma. based on what we presented in this paper, we argue that its contribution to the field of color study is to verify how color is used in professional practice. moreover, we aim to collaborate with the teaching of color so that designers can consciously apply color theory in their projects. 7. conflict of interest declaration the authors declare that there is no conflict of interest regarding the publication of this paper. 8. funding source declaration this work has been supported by funds from the state university of rio de janeiro (universidade do estado do rio de janeiro). 9. acknowledgement we wish to thank the state university of rio de janeiro (universidade do estado do rio de janeiro) on behalf of professor sydney fernandes de freitas, the cosupervisor of gisela monteiro doctoral research in the 2015-2018 period. 10. short biography of the author(s) gisela costa pinheiro monteiro design professor at universidade federal fluminense. doctor of science (uerj), master in design (uerj) and bachelor in industrial design (uerj). conducts research and teaches in the areas of design, color, visual perception, user-centered design, history and design theories. camila assis peres silva design professor at universidade federal de campina grande. doctor of science (usp), master in design (uerj) and bachelor in industrial design (ufrj). specialist in marketing and e learning (uff). conducts research and teaches in the areas of packaging design, color, visual perception, usercentered design, usability, history and design theories. notes [1] originally from portuguese: “pequeno quadrado impresso sólido (chapado), é acompanhada por uma referência técnica fornecida por um fabricante de tintas”. [2] during the conduct of this research between the years 2015 and 2018, we could find in the pantone help center the explanation about the relationship between its numbering and the parameters of hue, value and chroma. references araújo, k. (1991). ‘os sistemas de ordenação e classificação de cores: sua utilização na indústria têxtil e de moda’, revista química têxtil, [online] (33), pp.34-37. available at: <https://www.abqct.com.br/wpcontent/uploads/2019/05/qt_32.pdf> (accessed 7 july 2020). calanca, d. (2008) história social da moda. são paulo. editora senac são paulo. design council (2020). the design process: what is the double diamond? available at: https://www.designcouncil.org.uk/newsopinion/design-process-what-double-diamond (accessed 7 july 2020). designface (2020) ‘the history of pantone®’. available at: https://www.designface.co.uk/pantone-articles/pantone-history/ (accessed: 23 june 2020). lidwell, w., holden, k., butler, j. (2003) universal principles of design: 125 ways to enhance usability, influence perception, increase appeal, make better design decisions, an teach through design. massachusetts: rockport publishers. lipovetsky, g. (1987) l’empire de l’ephemère: la mode et son destin dans les sociétés modernes. paris: éditions gallimard. monteiro, gisela costa pinheiro (2018). o designer como o responsável por preservar a identidade da marca ao longo da produção das coleções de moda. 445 p. tese (doutorado em design) – escola superior de desenho industrial, universidade do estado do rio de janeiro, rio de janeiro, 2018. pantone (2015) ‘new tpg pantone fashion home + interiors color references produced with the environment in mind’. available at https://www.pantone.com/about/press-releases/2015/new-tpg-pantonefashion-home-interiors-color-references-produced-with-theenvironment-in-mind (accessed: 23 june 2020). pantone (2020a) ‘difference between the tc/tcx and tp/tpx suffix after the pantone color number’. available at https://www.pantone.com/customer-service/help/?t=differencebetween the-tc/tcx-and-tp/tpx-suffix-after-the-pantone-color-number (accessed: 23 june 2020). pantone (2020b) ‘shop all pantone products’ available at https://www.pantone.com/shop-all (accessed: 23 june 2020). régula, l. (2004). ‘padrões virtuais e tolerâncias colorimétricas no controle instrumental das cores. master’, master dissertation, pontifícia universidade católica do rio de janeiro, rio de janeiro. simmel, g. (2008) filosofia da moda e outros escritos. lisboa: texto & grafia. vincent-ricard, f. (1989) as espirais da moda. rio de janeiro: paz e terra. https://www.pantone.com/customer-service/help/?t=difference-between-the-tc/tcx-and-tp/tpx-suffix-after-the-pantone-color-number https://www.pantone.com/customer-service/help/?t=difference-between-the-tc/tcx-and-tp/tpx-suffix-after-the-pantone-color-number https://www.pantone.com/customer-service/help/?t=difference-between-the-tc/tcx-and-tp/tpx-suffix-after-the-pantone-color-number https://www.pantone.com/shop-all 42 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140105 two prizma color films, a curious finding in the mexican national film archive paolo tosini vulcanus film, italy, vulcanusfilm@gmail.com abstract few years ago an important collection of silent movies was found in the national mexican film archive. the collection did not contain any mexican movie, unfortunately, but it was rich in terms of coloring techniques of the silent era; two findings were particularly interesting, the first on the apache trail in the united states (around 1921) and the second on the clay making in ohio (probably 1920s). the added value of both titles is that they were shot using the prizma color technique, a very original color-processing invented around 1913 by william van doren kelley and charles raleigh. this color system was an additive color technique that eventually evolved into a bi-pack system. even if a complete restoration is not yet completed, the films were a particular challenge for a proper conservation and film restoration. the paper will examine the research on the film, the color process and suggest some possible restoration techniques. keywords prizma, prizma color, color restoration, film, digital restoration, mexico received 01/11/2021; revised 05/01/2022; accepted 27/01/2022 two prizma color films, a curious finding in the mexican national film archive 43 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140105 1. introduction in 2011, while working at the mexican national film archive, i discovered a collection of short films from the 1910’s created with unique coloring techniques. my quest to find out more about these films led me on an interesting path of discovery. two of the shorts used a lesser-known technology called the prizma color system, which was introduced in 1913 and disappeared in the 1920’s. in this paper, i will discuss this unique coloring system and describe the challenges in restoring this particular kind of technology. even if -regrettably none of these materials are mexican, they give us a glimpse into what the mexican audience used to watch in the ‘10s. 2. the prizma color origins cinema is a constant process of innovation; in any era of film history, we can find new systems, technologies or novelties. they all were invented to surprise the audience but also to push the boundaries and therefore the form of the movies. we live in a time where digital tools continue to expand the possibility of moviemaking, but technology has always shaped the way of making movies. since the beginning of cinema, producers, directors and cinema “inventors” were finding ways to add colors to movies; at the beginning with hand painted techniques, tinting, toning and -later onwith more complex mechanical techniques, before the era of multiple layer film material [1]. for the purpose of this research, we will examine one specific technique, known as prizma color. prizma color was a coloring technique invented by the prizma company, a company created by william van doren kelley, in the ’10s. van doren kelley (fig.1) fathered many original techniques (e.g. kesdacolor, kelleycolor). the prizmas (prizma i and prizma ii) were the results of many attempts carried out in the 1910’s and 1920’s to reproduce colors in the most efficient way. the first experiment of the prizma system was made in 1917 with “our navy”, a movie presented in the american a first experiment was carried out in 1913 with a more ambitious system, the panchromotion [2] a four color filter (red-orange, blue-green, blue-violet, yellow) technology that was meant to challenge the “kinemacolor”; the result was not successful especially resulting in color “fringing” (and optical aberration that occurs at the border of the image) and lack of projection brilliance. museum of natural history. “our navy” was made using a three-disk system which resulted in instability and flicker when projected, an issue true of many of the disk technologies used during that era. these required upgrading all the projectors and training the staff to achieve the perfect speed required by the system. fig. 1. william van doren kelley 3. prizma i as a result of these previous experiments, the prizma i system was developed by combining two techniques. a first frame was colored in red and orange and a second one in blue and green with an additive system. they were then combined with a color wheel. despite the fact that it was a combination of two different technologies, it continued to have fringing and synchronization problems, and van doren kelley was convinced that a subtractive coloring system would help to solve these issues. the visual result of these problems was called “bleeding” colors as the colors of the image were sometime “bleeding” out of the image; van doren kelley’s quest to solve this instability led him to create a new subtractive system – which resulted in having the colored “captured” on the material rather than adding color directly to the material. we must add that, in general, companies devoted to innovation in film production were devoted to more than one project, working on multiple levels to eventually achieve a goal, in this case to develop a more stable coloring system. in this case we have to mention that another coloring system was experimented by prizma, the kesdacolor. this coloring technique was first used on “our american flag” (1918). tt was also a two additive system but used a filter made with a lens and a prism to achieve a diffused light and compose the image [3]. two prizma color films, a curious finding in the mexican national film archive 44 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140105 4. prizma ii after few years of testing, on april 4th,1922 the prizma company patented a new system; the prizma ii, a complete shift in the previous projects of the company. prizma ii was a subtractive system to be projected on regular projector (vs. kinemacolor) anticipating “bipack” system. two films were shot simultaneously (fig. 2). one strip was sensitive to red-orange, the other to blue-green. both negatives were processed and printed on “duplitized film” (film material with emulsion coating on each side) and then each emulsion was toned its complementary color, bluegreen by an iron solution, and the opposite side redorange with uranium. fig. 2. prizma ii camera (jonathan silent film collection) fig. 3. prizma ii patent looking at the original patent (figs. 3-4) we can better understand how the original object was considered as decomposed by two negatives (a red and a green one), and printed on a positive, then dyed blue-green and redorange in a final complete positive copy. in this way, prizma ii was “imbedding” the color information in two negatives and untimely in one positive, so that could be projected in any venue, with no need for further technological upgrades. here is a very brief filmography of movies that were created with the prizma company systems and screened: • way down easy (1920) • the gilded lily (1921) • broadway rose (1922) • the glorious adventure (1921) also, 26 shorts (or more) were produced and released to demonstrate the prizma ii and in 1925 robert flaherty took a prizma ii camera to the set of “moana” (1926) but he was not able to shoot any material. the reasons for this are unclear. fig. 4. prizma ii patent as a conclusion to this very limited chronology of the prizma company, van doren kelley’s last project was the kelleycolor, which was unsuccessful. in 1928 all the patents belonging to the prizma company were acquired by the consolidated film industries part of republic pictures and were re-branded as magnacolor. two prizma color films, a curious finding in the mexican national film archive 45 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140105 5. two findings the mexican national film archive includes an interesting collection of nitrate materials. it is still unclear how much of the collection was destroyed in the fire of 1982 but since then there has been a big effort reconstruct what was lost. it is likely that a collection of 25 silent film were donated to the archive, although it was not possible to trace the original donor. these materials survived because in the 1940s this selection of silent films were used by a teacher as visual illustration for his geography and history classes. all of these titles are either travelogues (the non-fictional one) or historical films (the fiction ones) but they all have some particularly original coloring techniques. this research project was born when we found the first title “la senda de los apaches de arizona” or “the apache trail” (1919 ? [4]) (fig. 5), not the positive original copy but a a ’90 dupe negative copy of this short movie, meant to show scenes from the apache trail, taking advantage of the prizma ii system in big scenery shots. even if the collection had not been studied or restored at the moment of the finding, the ’90 dupe negative (as for some of the titles) clearly indicate that there was an intent to preserve the materials. by reading the edgemark on the positive, one could clearly see that the film had been made using the prizma system, and from there we began on our journey to discover the origins of this unique coloring technique. fig. 5. a frame of “the apache trail” another prizma title we found in the collection was “la industria ceramica” (1920?)(fig. 6), a movie that begins as sort of industrial documentary, but then moves more to a peculiar and imaginative creation as the beauties of the ceramic industry in ohio are shown by an exotic magician. the positive copy of the movie was also marked with the prizma brand and had the same color effects as well as the same problems. fig. 6. a frame of “la industria ceramica” 6. an attempt at restoration when dealing with such unique materials, the first concern was to understand as much as we could of the technique, including the desired color effects as well as the aberrations resulting from the failures of the of the prizma technique. as we first approached the dupe negative material of “the apache trail” we realized that the copying system (on eastman material) was actually quite accurate, but it was definitely lacking the brightness of the original. this idea was confirmed as soon as we find the original positive copy. after a complete inspection and reparation, we followed our regular scanning procedure of the laboratorio de restauracion digital elena sanchez valenzuela, the digital facility of the cineteca nacional: the three copies were scanned in a 3k resolution selecting accurate lut for each material. it became clear that three main problems we would face in the image and color restoration process would be heavy flickering, color instability, and “fringing” or “bleeding”. all three problems were created by the prizma system itself, which resulted in a color that was not always centered, a heavier than usual image flickering and an instability of colors in the image (and in the same frames) which caused a “fringing” or “bleeding” effect (fig. 7). it is probable that these defects were the main reasons why prizma was not widely used in its time. it must be noted that the system was mostly effective for scenes with limited camera movement (such as scenery shots) but definitely less effective in scenes that involved more action. we decided to apply a minimal stabilization to the image and, after many attempts, a minimal color correction was successfully applied to match the two original positives. two prizma color films, a curious finding in the mexican national film archive 46 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140105 fig. 7. a frame with a “bleeding effect” 7. conclusion finding a new collection is often the impulse for new research and can ultimately lead to significantly broadening the field itself, especially when there is little that is already known about techniques used to create them. the finding of two prizma color movies in a more complex collection in mexico reaffirmed that film history can be changed from any part of the world. while a final solution to correcting the “bleeding” problem was not found, we have hope that digital technology may, in the near future, be able to resolve it, perhaps with a digital division of color layers (maybe in a three-dimensional space, decomposing film material as complex object more than the result on the screen) or even without any intervention. 8. conflict of interest declaration the author declare that no financial/personal interests have affected the author's objectivity. therefore, no conflicts of interest exist. 9. funding source declaration this research has received no grant or funding from public institution, for profit or not-for-profit companies or agencies. 10. short biography of the author paolo tosini has studied film restoration in udine and berlin. he has been the founder and director fo the digital restoration lab in the mexican national film archive. he is currently the coordinator of the film heritage conservation school for the csc and teaches film history at the università del salento, lecce notes [1] for example, technicolor, eastman color, agfacolor, ferraniacolor but also dufaycolor, kinemacolor and gasparcolor among many others. [2] for more information: nowotny, r. a. (1983): “the way of all flesh tones. a history of color motion picture processes, 18951929” garland pub., pp. 154-156 [3] for more information: ryan, r. t. (1977): “a history of motion picture color technology”, focal press, pp. 34-35. [4] we estimated the year from the edge code of the stock material. references brown s., street s., watkins l. (edited by) (2013) “color and the moving immage. history, theory, aesthetics, archive” routledge schantz t. (edited by), (2004) “hollywood: critical concepts in media and cultural studies” volume 1, taylor and francis street s. (2013) “colour films in britain: the negotiation of innovation 1900-1955”, bfi flueckiger b., historical film colors: a guest entry from barbara flueckiger, available at: http://www.davidbordwell.net/blog/2021/02/21/historical-film-colors-aguest-entry-from-barbara-flueckiger/ (accessed: 3 november2021). timeline of historical film colors, url: https://filmcolors.org/ http://www.davidbordwell.net/blog/2021/02/21/historical-film-colors-a-guest-entry-from-barbara-flueckiger/ http://www.davidbordwell.net/blog/2021/02/21/historical-film-colors-a-guest-entry-from-barbara-flueckiger/ https://filmcolors.org/ 7 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130101 zhang yimou: great master of color lia luzzatto 1 , laura del zoppo 2 1 color and colors, milan, luzzattolia@gmail.com 2 film director, london, lau.dz@libero.it corresponding author: lia luzzatto (luzzattolia@gmail.com) abstract as a pioneer of chinese cinema, zhang yimou, has directed a number of films spanning various historical periods, genres and techniques, but if there is a style or technique that really defines him, this is the skillful, symbolic and communicative use of color. many critics claim that red is the color that voluntarily characterizes his films, but he himself tells how this distinctive preference of his first films was due to the environment in which he grew up in northern china, in which red for centuries has not only been the bearer of meanings, but also a cultural heritage, a representative sign of a past to be rediscovered and preserved. in fact, many aspects of the culture of this great country converge in red and in the term that translates it, so much so as to be a metaphor for customs, traditions and feelings. in this research we have tried to go beyond this cliché by taking into consideration the whole of his film production. we analyzed five films: two wuxia (a narrative genre, typical of chinese cinema, which mixes martial arts with fantastic and adventurous elements), the first hero (2002), where the color of the clothes, draperies and sets changes according to the unfolding of the story and the last, shadow (2018), in which the color belongs directly to the set design and costumes, and which brings us back to the black and white painting that inspired generations of chinese writers. then we analyzed three other historical-social films, red sorghum (1987), ju dou (1990) and raise the red lantern (1991) which represent chinese society in the 1920s and 1930s. in the analysis of these films we have been able to identify three different ways of using color: one narrative, one symbolic and one that we can define as historical-aesthetic. keywords china, cinema, communication, art received 05/02/2021; revised 29/03/2021; accepted 04/05/2021 zhang ymou: great master of color 8 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130201 1. introduction zhang yimou director, screenwriter and cinematographer of many of his movies is perhaps the most important director in contemporary china. his training passed through mao’s cultural revolution, which saw him working first in the countryside and then in a textile company, to arrive, after deng xiaoping’s reform, at the beijing film academy in the photography department. after collaborating with several directors as camera operator, set photographer and actor, he made his directorial debut with the movie red sorghum (1987) and became part of that large group of filmmakers defined as fifth generation. as a pioneer of chinese movie making, he has directed a multitude of films spanning various historical periods and genres, but if there is one style or technique that defines him, which connotes his works and is part of his poetic journey, it is the particular artistic, symbolic and communicative use of color: a tool that has always been used in traditional chinese theater to communicate situations, personalities, feelings, both in the courtly and popular culture, as well as in communist china with new meanings and new representations. a paradigmatic example and covered in every aspect in many of zhang yimou ‘s movies is the red color: in the past a precious dye obtained from cinnabar and since the time of the song dynasties used to color the seals placed by the literati on painting and calligraphy works. later it was the color of the revolution, of the red flags, of the little red book, and last but not least of the ‘red sun’, which is still the symbol of mao. we like to think that the director uses it to sign, as if with a seal, many of his works, even if he himself says that this color is simply that of the traditional culture in which he was born, a cultural heritage of northern china where he grew up and a representative sign of a past to be rediscovered and preserved. in this research we have considered the three movies with a social-historical character(red sorghum 1987, ju dou 1990, red lanterns 1991) that tell the story of china in the 1920s and 1930s and two wuxia 1 films, the first and the last: hero (2002) and shadow (2018). looking at the work as a whole, we identified three different ways of using color: symbolic, narrative and aesthetic. 2. the symbolic color many commentators claim that red is the hallmark of zhang yimou’s movies. in the works we have chosen to see and that describe a period that takes into consideration the 1920s and 1930s of chinese history, red is indeed one of the main protagonists. in red we find a symbolic and communicative complexity linked to the millennial history of this country, a history that is part of the tradition, beliefs and collective imagination. we have analyzed the various aspects of red in three movies, two of which also carry this color in their titles: red sorghum, jou dou, and red lanterns. these three movies are known to critics as the “red trilogy, both because they share the predominant use of this color in a palette reminiscent of that of ancient china where red and yellow and gray dominated imperial and popular culture, and because of a common concern for national identity, political engagement, and the human and natural landscape. "the dominant red of these movies has a double significant value: if for the western audience it becomes the main stylistic feature of the author... for the chinese it constitutes the occasion to recover, perhaps unconsciously, a heritage of symbols originally present in their own culture but later lost" (colamartino and dalla gassa, 2003)and the reds illuminate the screen, capturing the attention in the traditional silk dress of the chinese bride, draped inside the sedan while the conjugal procession crosses the fields, in red sorghum; they become dramatic in ju dou where, in the dyehouse, strokes of fabric from yellow to red unfold before the eyes of the spectator like strokes of paint on a canvas; and they permeate every scene of red lanterns, lighting up on the gray of the courtyard and becoming claustrophobic in the interiors. 2.1 red sorghum (1988) “red sorghum is one of the most important movies of the fifth generation for several reasons: it is the first chinese film to win a prestigious award, the golden bear in berlin in 1988." (colamartino and dalla gassa, 2003). it tells the story of the young and beautiful nine flowers sold as a bride to the old leper, owner of a red sorghum distillery and her love affair with the young yu, whom she marries after the death of her husband and with whom she has a son; the plot takes place against the backdrop of the japanese invasion of the '30s and will see nine flowers heroically fight for her country and die. red, the color that speaks of the immutability of the spirit and of chinese tradition, marks the opening scene of the film where the young bride is seated in a sedan chair covered with a fluttering fabric of this color and marks the end, where a solar eclipse accentuates the tragic dimension and red spreads across the screen. in the initial phases, intense red is used in the traditional sense, as a color linked to marriage, luck, love and wealth: red is the sedan chair, red is the dress of nine flowers, an intense red that occupies the scenes of the zhang ymou: great master of color 9 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130201 wedding, wanting to hide the unhappiness of the bride and capturing the attention and the gaze of the viewer. a red that runs through the tragedy of the sold woman and with which zhang yimou launches the social denunciation of a period that the revolution has now left behind. behind this color lies the tragic fate of many women anchored to the customs of a feudal society where red, from a symbol of love and happiness, became a sign of male power. in this color, so rich in shades and meanings, tragedy, violence, sin and war also unfold: when japanese troops invade china, including the village where nine flowers lives, she will organize the resistance, dying for the freedom of her country in an apotheosis of warm and dramatic orange and red tones. in this movie the symbolism of red is clear: on the one hand it underlines revolutionary commitment and on the other hand passion and love. by presenting itself in a recurring way dress, liquor, fire, blood it captures and guides the attention of the spectator. 2.2 ju dou also in this movie, the director denounces the medieval custom of buying wives. ju dou is the wife bought by jinshan, an old and impotent dyer, and she engages in a romance with tianqing, a nephew of her master who works as an apprentice in the dye shop and with whom she has a son. the movie is set in a rural textile mill. throughout the movie, ju dou and tianqing are oppressed by jinshan 's tyrannical, suffocating, and vigilant behavior, and even after his death, ju dou and tianqing cannot live as they wish because they struggle to appease cultural expectations and hide their illicit relationship. the movie ends in an extremely dramatic way: tianqing is murdered by their own son and ju dou kills herself by burning the mill around her. in this movie red recalls its very archetypes: blood and fire. with blood it shares the sense of life in the most intense and transgressive parts of sex and death, with fire that of purification and destruction. it is the red dye poured into the dyeing tub that heralds the final drama of the death of two of the male performers pushed and drowned in that tub, one almost by accident and the other by revenge; both ju dou 's husband and her lover lose their lives in this colored water. it is a red that marks loss: loss of purity during the sex scenes, loss of honor, loss of husband and lover, loss of the murderous son, and marks the unfolding of the drama by accompanying the viewer, as in red sorghum, in the red light of the expiatory fire. once again, color becomes a fundamental element of the story, underlining its emotional phases: from purple red to golden yellow in the clandestine relationship, turning into dark and livid tones in the tragic finale, a single color presented in different shades to portray passion, jealousy, revenge and ‘crime’. 2.3 red lanterns (1991) in this movie, the last of the trilogy, which earned zhang yimou the silver lion at cannes, the director once again puts the eastern patriarchal order under indictment. the setting is pre-revolutionary china, and the theme is the relationship between sexes. the story takes place in the 1920s and is about the young and beautiful songlian who is forced to abandon her studies due to the death of her father and marry chen, a rich landowner who already has three wives. the plot takes place inside the gray and cold courtyard on which the doors of the rooms of the concubines and that of the owner open. the only colorful element is the red of the lanterns that are lit near the door of the concubine with whom the man decides to spend the night. the women compete for exclusivity over the husband and a fierce rivalry arises that results in a bitter ending.(moviestruckers, 2017). songlian, in order to gain her husband's favor, lies about being pregnant and when she is discovered, after a series of dramas, she goes crazy. the lighting of the lanterns is a sign of status for the concubines because whoever wins her husband's favor receives an elaborate foot massage and the right to decide the menu for the entire family the following day. it is therefore the red of the lit lanterns or the black of the drapes that cover them to mark the moments of the tragedy, and it is always a radiant red light, diffused in the rooms together with the furnishings and the clothes of this color to mark the desire, the love and the tragic destiny of the protagonist, a red symbol of wealth, dominion, power, sex that in the denunciation becomes also a symbol of oppression. 2.4 red in the trilogy in these three movies, red defies any narrow interpretation, because it indicates both a rejection of tradition and its heritage. it is no longer a celebratory color as in ancient china or revolutionary as in modern china, it could be described as a state of mind, as a feeling. as zhang yimou once said, “we chinese have been too moderate, too reserved... the boundless red of sorghum fields arouses sensory excitement... it encourages the joy of living." (gateward, 2001). in his movies, red becomes the primary color of life and in the course of the events of the trilogy it becomes a commemoration of freedom, exuberance and the most primitive and natural desires and aspirations. zhang ymou: great master of color 10 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130201 3. narrative color: hero (2002) hero is the first wuxia film made by zhang yimou in 2002. the story takes place in china in the historical period called 'of the fighting kingdoms'. indeed, the chinese territory was divided into seven kingdoms that fought for supremacy, the most powerful of which was the kingdom of qin. the plot, simple and complex at the same time, is based on the true story of jing ke (nameless) a swordsman who prepared for ten years to kill the king of qin (227 bc). in the movie jing ke is nameless, an unknown swordsman who one day presents himself to the king of qin saying that he has succeeded in killing all those who plotted against his life. nameless refers to sky, an assassin, unbeatable with a spear, to flying snow, a woman and a skilled swordsman whose family was exterminated by the king, and to her lover broken sword, an extraordinary master both in swordsmanship and in the art of calligraphy. however, during the story, the king realizes that nameless is deceiving him and that this was a way to get close to him and kill him. the complexity comes from the director’s choice to narrate the events seen from different angles with different levels of truth, so that the audience can learn about facts and characters from different standpoints. a choice made by other directors before him, such as quentin tarantino and akiro kurosawa, but what makes this choice different, unusual and original is the use of color. indeed, it is the color of the scenes, of the clothes, of the furnishings, in which the characters act that marks the unfolding of the narration in a discontinuous continuity that leads from deception to truth. the story relies on flashbacks, wonderful pieces of dazzling colors that involve the viewers and guide them into the complexity and ambiguity of the events. black, red, blue, white and green are the five colors chosen by the director to mark the timings and to identify with immediacy the direction of the story: colors that also involuntarily expand their allegorical dimension and influence the perception of time that in the red seems to flow faster, while in the blue, despite the action, it becomes slower and contemplative. the author, in the interviews following the film’s release, excluded that he wanted to use color in its symbolic dimension and that he had given it more simply the task of separating and unifying the story in an immediate, easy, safe and aesthetically involving way, so as to guide the spectator across the film’s complex plot. in reality, given the intrinsic characteristic of color to express universal meanings and emotions deriving from its archetype, we can observe how the chromatic alternations are in harmony with the contents of the story. different colors to represent the inner worlds and situations of the different characters. because in hero there is everything: love, hate, revenge, resentment, art, gracefulness, elegance and violence. black is the color that marks the beginning. black are the palace, the garments of nameless, the soldiers’ armor, the king’s dress; a black emphasized by the fixity of the image with the main character at the center of the scene. and black concludes the movie, a hard, contracted black that promotes an aesthetic of cold-blooded, fearless death. between these two blacks the colors of the story unfold. red marks jealousy, betrayal, revenge, love and passion, and pride among the fighters that unleashes a centrifugal force underscored by the flight of leaves and flying sand that permeates the scene. it is the fire of jealousy that will bring death to the swordsmen. the blue following the red shows us the story as seen from a different angle. in this color it is the outdoor space that dominates the action and gives the scene a sense of calmness and serenity emphasized by the camera that slowly follows the movements of the swordsmen and emphasizes the lightness of their clothes and the air. white, color of mourning, death, but also of purity wants to assert the actual innocence of the swordsmen: in ancient times in china it was thought that a change of dynasty was not a mistake, but it was necessary when an emperor did not rule according to the confucian rules of good governance. in this way, the end of a dynasty preluded to a new and better life for the empire. when the story is colored with green, the feeling is that this color is the most suitable to describe the feeling of peace and joy that breathes in the hearts of the second and third swordsmen. in addition to marking the final change in the story, this shade of green reminiscent of jade, for the chinese since ancient times a rare material with esoteric virtues, symbolically reveals victory over death. nameless dies, but he will be given the solemn funeral that is usually arranged for heroes: the promise and guarantee of a long life in the memory. 4. aesthetic color: shadow (2018) based on the novel of the three kingdoms, a classic of chinese literature, shadow tells the story of an ambitious king determined to regain a part of the kingdom and his great general, commander zi yu, a visionary man driven by the desire to win, but forced, since he lacks the strength, to use a double to fight in his place: his shadow, zhang ymou: great master of color 11 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130201 a peasant who resembles the commander and replaces him when necessary and with whom he also shares his wife, but not the nuptial bed. both characters are played by deng chao. the plot is complex, full of intrigue and references, dominated by the sign and metaphor of yin and yang, the two opposing principles that involve, in addition to motion and stillness, a long series of contrasting elements: light and darkness, hot and cold, expansion and cohesion, evolution and involution, activity and rest, life and death, male and female (luzzatto, 2019)whose image is proposed in more than one occasion to narrate the light and "shadows" of the protagonists. "the main theme is that of the double: the original and its shadow, the true and the false, but also the masculine and the feminine. a game of pairs that is extraordinarily marked on a chromatic level by black and white, with the photography of zhao xiaoding that almost exclusively uses shades of gray"(balsamo, 2018). the story unfolds in the beginning in a measured and dare i say guarded way to then accelerate with dramatic contours in the final in a claustrophobic landscape where rain continues to pour down. we are a long way from the masterful colors of hero: the fiery reds, the tranquil blues, the purifying whites... in this movie the palette uses the many shades of gray between a sometimes dazzling white and a deep black, turning also to ‘colored grays’, those shades that carry the memory of a hue. after the first scenes, the colors sneak in, they are those of the skin, the dark red of blood, the memory of the green of the vegetation... the characters live, plot, attack, defend themselves and die, in incredible varieties of a sometimes unnerving gray a choice that the director claims to have been inspired by chinese brush painting, the one that shitao, a painter and poet who lived during the qing dynasty (1642/1707), wrote about: "the one stroke carries within the totality of beings. the stroke receives the ink, the ink receives the brush, the brush receives the pulse, the pulse receives the spirit." (shitao, 2008) (luzzatto, 2019 page 77). a monochrome painting obtained from the dilution of black ink, by which generations of artists-literates have been inspired, submitting themselves to a strenuous spiritual exercise aimed at recreating the cosmic and natural order where “everything is in relation and where the one, the void, the creative power that contains everything, becomes two originating the pair yin (black) and yang (white): the opposite and complementary movements that enable every form of life and according to which reality is expresses itself" (luzzatto, 2019). so in this work of his maturity zhang yimou, who has always looked to the aesthetic-symbolic tradition of his country, deeply anchored in its ancient history and in the confucian and daoist tradition, tried his hand at the artistic tradition deriving from buddhism, painting the scenes with a meticulous and monochromatic choice of places, environments and furnishings and with masterful framing, camera movements and photography. the yin/yang symbol often appears on the ground during filming and refers to its philosophical complexity: it is a fighting arena for the commander and his shadow, it is the preparation of the shadow that, in order to train for the fight, takes possession of the feminine side of his lover, making his own the axiom that nothing can be completely yin or completely yang because both contain the seed of their opposite. there are many references, especially in the landscape, to the scrolls of the ancient masters with the contours of the hills that emerge from the mist, the pouring rain and the dark tones of a gray that turns to black sometimes emerging from an intense white, like ink on white paper. the feeling is that the events take place in a darkness that from the rainy exterior spreads to the interior like an immense shadow. the eye gets lost in the formal and chromatic refinement, which is not absence, but reduction and follows the unfolding of the representation as in the ancient paintings painted on vertical scrolls that were hung on the wall and whose vision was accomplished slowly in their unfolding, as a succession of images on the screen. for a general discussion of the topics covered in this article (zehou, 2004). 5. conflict of interest declaration the authors declare that nothing affected their objectivity or independence and original work. therefore, no conflict of interest exists. 6. funding this research did not receive any specific grant from funding agencies in the public, commercial, or not-forprofit sectors. 7. authors short biography lia luzzatto essayist, publicist and chromatic consultant. professor of color theory in university faculties, she participates and organizes seminars and courses in italy and abroad. she is the author of numerous historical and educational books on color, an interest that she started from the lessons of luigi veronesi at the brera academy of fine arts. zhang ymou: great master of color 12 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130201 laura del zoppo graduated from the brera academy of fine arts, she is a director and art director. she has made numerous broadcasts and commercials for various television networks. she has had teaching positions in several private academies in the history of contemporary art and fashion show production courses. notes [1] with wuxia we mean a narrative genre, typical of chinese cinema, which mixes martial arts with fantastic and adventurous elements. references balsamo, m. (2018) ‘shadow: le ombre viste da zhang yimou con una scelta cromatica straordinaria [recensione]’, anonima cinefili, 2 october. available at: http://www.anonimacinefili.it/2018/10/02/shadow/ (accessed: 5 february 2021). colamartino, f. and dalla gassa, m. (2003) il cinema di zhang yimou. genova: le mani ed. gateward, f. (ed.) (2001) zhang yimou: interviews. illustrated edition. jackson: university press of mississippi. luzzatto, l. (2019) cina: cronaca dei cinque colori. 1° edizione. franco angeli. moviestruckers (2017) ‘zhang yimou: la donna, un fiore che non può dischiudere i suoi petali’. available at: https://www.moviestruckers.it/approfondimenti-film/zhang-yimou-figuradonna-film/ (accessed: 5 february 2021). shitao (2008) sulla pittura. sesto san giovanni: mimesis. zehou, l. (2004) la via della bellezza. torino: einaudi. color culture and science cultura e scienza del colore ccsj volume 13 number 2 2021 issn 2384-9568 color culture and science journal cultura e scienza del colore ccsj jcolore.gruppodelcolore.it issn 2384-9568 doi: 10.23738/ccsj.00 ance: e227716 registrazione tribunale di milano n. 233: 24/06/2014 anvur agenzia nazionale valutazione sistema universitario e ricerca apej academic publications ejournal base bielefeld academic search engine dbh database for statistikk om høyere utdanning doaj directory of open access journals ezb elektronische zeitschriftenbibliothek regensburg jurn search tool for open access content road directory of open access scholarly resources volume 13, number 2, november 2021 doi 10.23738/ccsj.130200 publisher gruppo del colore – associazione italiana colore www.gruppodelcolore.org registered office: piazza carlo caneva, 4 20154 milan (it) peer review process all articles submitted to the color culture and science journal are peer-reviewed according to the following procedure: first review level the associate editors evaluate each article to determine if the topic and content are of interest to the journal. once the article passes the initial review, the associate editors select several reviewers from the editorial board based on their expertise in a particular subject area or topic. second review level two or three experts review each article with a blind peer-review process where the reviewers are kept anonymous. reviewers are asked to evaluate the manuscript based on the following criteria:  originality  relevance to journal's aims and scope  technical merit and/or validity  soundness of methodology  completeness of the reported work  conclusions supported by the data  correct acknowledgment of the work of others through reference  effectiveness of the manuscript (organization and writing)  clarity of tables, graphs, and illustrations  importance to color researchers  relevance to color practices if the article is accepted with major revisions, the author(s) are asked to improve the article according to the reviewers' suggestions. the revised article will then be submitted for further review. after collecting the reviewers' reports, the associate editors recommend the acceptability of the article to the editor-in-chief. editor-in-chief maurizio rossi (politecnico di milano, it) deputy editor alessandro rizzi (università degli studi di milano, it) associate editors josé luis caivano (universidad de buenos aires, ar) vien cheung (university of leeds, uk) marco gaiani (alma mater studiorum università di bologna, it) robert hirschler (serviço nacional de aprendizagem industrial, br) agata kwiatkowska-lubańska (academy of fine arts, kraków, pl) marcello picollo (ifac-cnr, it) verena m. schindler (chair aic s.g. environmental colour design, ch) renzo shamey (nc state university, usa) francesca valan (studio valan, it) editorial board members the complete and updated list of the editorial board members involved in the peer review process is available on the ccsj website: http://jcolore.gruppodelcolore.it/ojs/index.php/ccsj/about/editorialteam topics the ccsj accept papers on a wide range of topics on color, including and not limited to the following: 1. color and measurement/instrumentation. colorimetry, photometry and color atlas: method, theory and instrumentation; quality control and food coloring, dyes, organic and sustainable color. 2. color and digital. reproduction, management, digital color correction, image processing, graphics, photography, film and video production, printmaking and 3d print, artificial vision, virtual reality, multispectral imaging, data visualization. light field imaging. multi-sensor fusion. color localization, recognition, hdr imaging, adas systems. 3. color and lighting. metamerism, color rendering, adaptation, color constancy, appearance, illusions, color memory and perception, color in extra-atmospheric environments, lighting design, lighting technologies, visual comfort. 4. color and physiology. mechanisms of vision in their experimental and theoretical aspects, color vision and color appearance, deficiencies, abnormalities, clinical and biological aspects, synesthesia, health, well-being. 5. color and psychology. phenomenology of colors, color harmonies, color & form, perceptive, emotional, aesthetic, and diagnostic aspects. 6. color and production. food and beverages, agriculture, textiles, plastic materials, ceramics, paints, gemology, color in the food industry. 7. color and restoration. archaeometry, painting materials, diagnostics, and conservation techniques, restoration, and enhancement of cultural heritage. 8. color and environment. representation and drawing, urban planning, the project of color, architecture, interior design, landscapes & horticulture, color and architectural syntax, territorial identities, biodiversity. 9. color and design. furniture, cmf design, fashion, textiles, textures, cosmetics, food design, museography. 10. color and culture. arts and crafts, history, philosophy, aesthetics, ethno-anthropology, graffiti, geology, sociology, lexicology, semantics, anthropology of vision, food culture and heritage, color naming. 11. color and education. pedagogy, didactics of color, aesthetic education, artistic education. 12. color and communication/marketing. graphics, communication, packaging, lettering, exposure, advertising. http://jcolore.gruppodelcolore.it/ojs/index.php/ccsj/about/editorialteam 3 color culture and science journal vol. 13 (2) issn 2384-9568 table of contents editorial 5 maurizio rossi zhang ymou: great master of color 7 lia luzzatto, laura del zoppo doi: 10.23738/ccsj.130201 a didactics of colour based on an innovative educational approach at the hochschule für gestaltung in ulm 13 annamaria poli doi: 10.23738/ccsj.130202 color and materials in design didactics. design of a playroom and relaxation area for children – case study 27 anna kmita doi: 10.23738/ccsj.130203 visual grouping: a study on preponderances of color or shape in match-three games 34 joyce c. cavallini, paula csillag doi: 10.23738/ccsj.130204 is white skin really pink? flesh color as a pink color in western art and culture 42 kévin bideaux doi: 10.23738/ccsj.130205 geometric models for color perception 50 nicoletta prencipe, edoardo provenzi doi: 10.23738/ccsj.130206b the red of lina and oscar 57 luiza paes de barros camara de lucia betlramini, paulo césar castral doi: 10.23738/ccsj.130207b 4 color culture and science journal vol. 13 (2) issn 2384-9568 the changes of transparent colours in being laid upon others': considerations for a new perception of glazes with historical pigments and dyes 64 miquel herrero-cortell, paola artoni, marcello picollo, marta raïch, maria antonia zalbidea doi: 10.23738/ccsj.130208b a test on color discrimination in complex scenes for a better comprehension of color blindness 72 s. scipioni, c.a. lombardi, l. giuliani, a. mazzoni, r. marcucci, a. plutino, a. rizzi doi: 10.23738/ccsj.130209b umbrella diagram: 1981-2021, five decades of forecasts and cmf design 84 clino trini castelli doi: 10.23738/ccsj.130210b 5 color culture and science journal vol. 13 (2) issn 2384-9568 editorial as our readers know, this journal is published by associazione italiana colore. the fact that it is diamond open means that it is free even for authors. this is a distinctive element of its publisher, a non-profit association, which stands in contrast with the many science predators present worldwide today. it is worth mentioning that in september 2021, the associazione italiana colore organized the aic2021 14th congress pursuing the same ethical principles. the international color association (aic) congress is a unique multidisciplinary event that brings together scholars and professionals from various fields. it has been held every four years since its inception in 1969. in 2021, it was hosted in italy, for the first time, organized by the associazione italiana colore. the covid19 pandemic imposes multiple constraints all over the world. in italy, the state's laws and the safety rules of the previously chosen venue (ca' granda, università degli studi di milano) prohibited any socializing, which is one of the fundamental reasons for the participation in presence. moreover, due to travel-related risks and restrictions, the associazione italiana colore, in agreement with the aic, has decided to organize the aic 14th congress online in compliance with the program elements required by the aic rules: opening ceremony, awards, aic general assembly, aic study groups workshops and closing ceremony. in aic2021, which should have been in presence, we wanted to create an ethically sustainable congress, thinking about young people, retired people, and professionals who cannot afford to spend too much to attend a congress. this was our leading idea since 2016 when we proposed italy to aic ec in santiago. following this idea, the early registration fee available since 2020 for the 14th aic congress was about half that of the previous congress. on january 5th, 2021, in agreement with the aic, it was decided that, due to covid19, the aic 14th congress should be held online. therefore, it has agreed to halve further the early registration fee, which is less than a quarter of the previous congress, lower than the fee of students and the single-day fee of the previous congresses. with a fee equivalent to what used to be the registration of a single day, now participants could follow in the entire five-day congress. to achieve this goal, the aic2021 congress is organized and directly administered by associazione italiana colore, a nonprofit association. associazione italiana colore could have decided to delegate the organization and administration of the congress to a company specialized in the organization of events, but this would have more than doubled the current registration fee even for an online congress and would also have added vat (+ 22% in italy). for a 5-day online congress, this would have resulted in doubling the registration fee. this has been possible thanks to the volunteer work of the members of the associazione italiana colore in the organizing committee, which i want to acknowledge and thank. maurizio rossi ccsj editor-in-chief full professor of design politecnico di milano 6 color culture and science journal vol. 13 (2) issn 2384-9568 131 color culture and science journal vol. 14 (1) book review: light the color of desire renata pompas andrea dall'asta: light the color of desire, ancora editrice, milan, 2021. in this second book dedicated to light in art, andrea dall'asta tackles modernity, after analysing its presence in antiquity in: "the light splendour of truth” (see: color culture and science, nm. 10 december 2018). the author, continuing the path of analysis and research on the tension towards light, asks himself whether in contemporary art light is symbolic, physical, or simply functional, and answers in seven chapters: seven interdisciplinary paths starting from impressionism to monochromy, through the icon-works of some artists, including at the end of the book, also sacred architecture, photography and cinema. chapter i the light of impressionism: completion of a western journey? the 19th century ends with monet's color, who in the landscape in "impression, sunrise" shows a phenomenological vision of light (1872); with seurat's color, who in "a sunday afternoon on the island of grande-jatte" shows a system of optical rules (1884); and with cézanne's color, to whom the author dedicates intense pages, who in "still life with peaches and pears" (1889) revolutionises the representation of light in the image, in fact: "from within the thing comes a light, as if it were its splendour, its éclat". chapter ii the twentieth century: the dissolution of the 'realm' of representation in the new century, philosophy rethinks itself, aesthetics and the function of art, which the author compares. chapter iii the modern icon and the spiritual power of color the 20th century opened with the renewal of oriental spirituality of byzantine origin, led by two russians: kazimir malevich and wassilji kandinsky, the former with his radical rejection of all representativeness that in the painting "black square on a white background" (1915) partially hides the light of the cosmic white background with the black of alchemic lead and the latter, as a true synesthete, creating the structure of a metaphysics of colors, based on the construction of a sound symphony: a music of the celestial spheres. chapter iv a journey into the beyond. beyond the perception after the second world war, research into color and light in art achieved results on the borderline between aesthetics and mysticism. yves klein's radiant colors, reach the limits of visibility through luminous blue; mark rothko's colors "create the sensation of an evanescent movement of matter" in which color becomes light, atmosphere, even in the very dark tones of the rothko chapel, where they "shine a kind of black light". the american barnett newman vertically crosses his monochromes with zips as rhythm, separation, wound. chapter v light is the material of the work! there are beautiful the pages dedicated to lucio fontana and his relationship between light/space/time and to the spirituality inherent in his works, where the holes and cuts show a further space that "is neither physical nor 132 color culture and science journal vol. 14 (1) perspective, but cosmic, infinite, illuminated by the light that enters and spreads", or to the installations with neon light or wood's light, where the spectator loses his bearings and feels disoriented. he describes nanda vigo's immateriality of the play of reflections and light; of james turrell and irwin's ganzfeld, the a-directional immersive spaces that seem to be a journey through a giant three-dimensional monochrome; of dan flavin's the environments enveloped in the intensity of light-color energy. then he describes contemporary research on monochrome: the changing colors of david simpson's canvases, the rgb led projections of pietro mega's "blue church", the constant and elusive flow of light in shay frisch's modular elements, the meditation on light in ettore frani's works. chapter vi light in sacred architecture in contemporary sacred architecture it is emptiness that dictates the spatial and functional relationships, and light is a protagonist: now purely functional, now symbolic. dall'asta looks for the most spiritual expressions, from the beginning of the 20th century to the present day. the beautiful pages devoted to the chapel in vence (france) created by henri matisse (1949-1951), focus on the warm light of provence that illuminates the chromatic symphony of the pure colours of the partly transparent and partly frosted stained glass windows. are at the opposite the 104 aniconic stained-glass windows by pierre soulage in conques (france, 1994) and the gerard richter's abstract stained-glass windows in cologne (germany, 2007). tadao ando's church of light in ibakiri (japan, 1989) pierces the deep darkness of the ascetic, bare chapel with a crossshaped slit in the solid concrete walls. also are described the friedrich f. haindl's church in munich (germany, 2000), the peter zumthor's extraordinary chapel built like "a cave dug into the belly of the world" in wachendorf (2001). among the italians, mario botta's churches and the mystical chapel of villa serena (2017) by ettore spalletti, drowned in the metaphysical silence of its blue hues. chapter vii photography and cinema: the landing of a long journey? since photography, as the term itself composed of phòsphotòs (light) and graphé (writing) says, is "a writing of light", as is cinema, to which movement and time are added, dall'asta traces a brief history of the two arts, in which photography and cinema are seamlessly intertwined. conclusionsvii an exciting, well-documented, original and unmissable book for all those who are passionate about art, light and colour. 53 color culture and science journal vol. 12 (2) doi: 10.23738/ccsj.120207 food waste: potential bioresource for the colour of polymers annalisa di roma1, alessandra scarcelli1 1 department of dicar, polytechnic university of bari, bari, italy. annalisadiroma@poliba.it, alessandrascarcelli@ poliba.it corresponding author: alessandra scarcelli, alessandra.scarcelli@poliba.it abstract the paper proposes the results of the research carried out by the authors on the theme of sustainable product design starting from the material component. in this context, there is a significant link between bio-materials and their chromatic value, originated by the pigment of natural origin, which is mainly responsible for the aesthetic characterization of the product. to support this thesis, a methodological approach has been adopted, developed in two phases: the first is critical analytical (desk) and identifies the framework of the research and the state of the art; the second is applicative experimental (field) and proposes some original experiments that include both the definition of new polymeric materials, obtained by adding waste coffee and sea urchins, and the characterization of optical and chromatic qualities, also conducted through technical tests instrumental mechanical strength. the results of the research arrive at hypotheses of mechanical and optical characterization, however the scalability of the results to the industry would require the use of appropriate instrumentation in the preparation phase of the materials (in this phase of study they were composed through an artisanal approach). keywords food waste, organic colour, bioresource, sustainable product design, digital manufacturing received 16/12/2019; revised 31/03/2020; accepted 11/05/2020 food waste: potential bioresource for the colour of polymers 54 color culture and science journal vol. 12 (2) doi: 10.23738/ccsj.120207 1. introduction the paper proposes the results of the research carried out by the authors on the theme of sustainable product design starting from the material component (di roma et al. 2019). this research was carried out in the design_kind research and teaching laboratory, with the collaboration of the company crea 3d and the mechanical testing laboratory of the dmmm department of the politecnico di bari. in the field of product design, there is a significant link between biomaterials and their chromatic value, originated by the pigment of natural origin, which is mainly responsible for the aesthetic characterization of the product. to support this thesis, a methodological approach has been adopted, developed in two phases: the first is critical analytical (desk) and identifies the framework of the research and the state of the art; the second is applicative experimental (field) and proposes some original experiments that include both the definition of new polymeric materials, obtained by adding waste coffee and sea urchins, and the characterization of optical and chromatic qualities, also conducted through technical tests instrumental mechanical strength. the logical bases of the research are based on the need to offer a critical contribution to the reflection of design, which on the one hand is measured by the theme of environmental pollution associated with the production and use of synthetic dyes, on the other hand defines a new phase of material culture that is based on the (re)acquisition of an aesthetic sensitivity associated with natural materials, with particular reference to those obtained using waste from the food and non-food sectors of the agri-food (scarcelli 2017). with reference to the state of the art of the artistic industry, the paper shows how colour has always played a fundamental role in describing the link between the aesthetic sensitivity of a civilization and the technical means at its disposal (kubler 1976): the culture of colour is the synthesis of scientific and technological innovation and the artistic sense of time. it is argued that in the "chain of time" that links colour to material culture, humanism and the first industrial revolution have impacted with profound changes. with reference to the current scenario, the development of a new approach to the theme of color as a material that supports the growth of green chemistry through experimentation and self-production of bio-materials is highlighted. 2. return to the origins of the material colour in the history of art and artistic manufacture, colour takes on a primary role, since each civilisation, starting with the first representations on the rocky walls of the lascaux caves, has been characterised by its own culture of colour. scientific discoveries and technical innovations accompany the evolution of the chromatic world in art, translating into tastes and styles shared by the material culture in the most common objects of use, from pottery to clothing. coloring the material means knowing how to masterfully manipulate pigments, tints and dyes; it means knowing ancient recipes and procedures to be skilfully adopted on different supports. in the ancient world, this science had a precise name, before becoming chemical: alchemy. until the dawn of the fourteenth century, color was a priority in art, evident in the recognized expertise of the artist in the preparation of colored powders, like the craftsmen: the color was produced in the workshop, with processes of manufacturing of organic and inorganic materials made available by the local land. “this is the why the grinding of a colored powder may affect its hue a phenomenon exploited by the artists of the middle ages, who controlled the shade of a pigment by the degree of grinding“ (ball 2003). among the guild of arts and crafts of florence, in the '300 painters chose to join the art of medici and speziali precisely because of the presence of pigments and dyes in their shops. humanism led to a separation of art from technique, of intellectual activity from manual activity, and this led to a greater attention of artists to the role of drawing at the expense of color, which remained an exclusive activity of craftsmen, especially ceramists, glassmakers, goldsmiths and tailors: the pigments were no longer processed by painters but purchased ready by traders, in increasingly wide color ranges. the advent of the industrial revolution, in addition to determining new market needs and new quantities to be satisfied in the consumption of goods of use, introduced the chemical industry of colorants into the artistic world, able to produce synthetically in the laboratory products cheaper, in practical tube packaging, and especially available in colors until then unimaginable. the colour naming, previously associated with the material origin, is identified by a number perfectly corresponding to its reproducibility according to artificial processes: red, for example, is no longer cinnabar, carmine or purple but, choosing the colour coordinates in cmyk, becomes 0-80100-0, 0-75-42-1 and 30-100-100-0. in other colour systems it is possible to obtain other codes which, however, do not tell us anything about the colour or its history (di roma and scarcelli 2017). another fundamental aspect of modernity is represented by the affirmation of the solid colour, which underlines the need to standardise and make constant the colour of a material in all its consistency, highlighting the artificial character of food waste: potential bioresource for the colour of polymers 55 color culture and science journal vol. 12 (2) doi: 10.23738/ccsj.120207 the perfect industrial product against the inconstancy of the imperfect handmade product. "la frequentazione dei linguaggi industriali comporta infatti che del colore oggi predichiamo prevalentemente la tinta… quando diciamo “tinta”, diamo per scontato che sia unita. insieme ai pigmenti sintetici, quest’idea di compattezza è forse la vera e più importante novità del mondo moderno" (falcinelli 2017). 3. research framework the theme of colour associated with industrial products is fully integrated into the history of industrialism and identifies the area that has given rise to the development of the contemporary chemical and pharmaceutical industry. "il maggior sforzo della chimica industriale fu quello di produrre tinte derivandole dalle scale coloriche di quelle naturali già selezionate dal gusto e dall'occhio, ma imponendo, infine, quelle prodotte come più convenienti ed eliminando di fatto quelle più rare, care e di difficile produzione" (brusatin 1999). as far as the development of the material is concerned, there is a progressive substitution of the raw materials of organic origin with the polymeric materials of fossil matrix and by chemical synthesis. "i coloranti sintetici, vengono facilmente inglobati nella massa plastica durante il processo di stampaggio; ciò fa si che il colore diventi il carattere distintivo del design del tempo, che dall’imitazione dei marmi e madreperle passa a sapienti “urli” cromatici che denunziano la loro artificialità, spesso ispirata all’uso ardito dei colori dei fauves; agli inizi degli anni ’30, la catalin corporation, la più importante ditta statunitense a produrre oggetti in resine fenoliche fuse, comprendeva 200 tinte, dai colori compatti e pastello a quelli traslucidi e perlati" (ferrara 2012). on the other hand, today, the theme of sustainability applied to materials and products opens up a new phase of reflection in design that goes hand in hand with developments in the so-called green chemistry industry. in this context, the contribution of scientific research on bioplastics is of great importance: these, in fact, give back to the reflection of design the chromatic qualities of the material in its natural meaning. in particular, the "artisan" production of the product from the material defines a new field of experimental research and the self-production of the material (rognoli et al. 2015) thus becomes an indispensable moment in the definition of the new product. a new dialectic is established between material and product: one influences language, the other influences the technical performance of the product. below is a selection of case studies identified during the desk phase of the research that defines the framework of the proposed research: the main assumption is the aesthetic value of the bio-based polymer, rather then the technical performance, this in order to define and develop a new sensibility on color. 3.1. shellworks this is a project carried out by ed jones, insiya jafferjee, amir afshar and andrew edwards of the royal college of art and imperial college of london that develops a system of machines and instrumentation suitable for the extraction of chitin from the exoskeleton of crustaceans. the aim is to produce biodegradable and recyclable disposable packaging from crustacean waste (fig. 1). chitin is a biological polymer that, when mixed with vinegar, produces a bio-plastic. the chromatic gradient obtained is the result of the different type of vinegar used and the different dosage of the components, which is also associated with a gradient referred to the optical clarity of the material and the different specific thickness. fig. 1. shellworks (2019) at the royal college of art and imperial college london by e. jones, i. jafferjee, a. afshar and a. edwards. bioplastic based on vinegar and chitin extracted from the shell of crustaceans. image courtesy: www.dezeen.com/2019/02/22/shellworksbioplastic-lobster-shell-design) food waste: potential bioresource for the colour of polymers 56 color culture and science journal vol. 12 (2) doi: 10.23738/ccsj.120207 from scientific literature it is evident the wide interest in chitin and its main derivatives (chitosan), because this new family of biological macromolecules shows excellent proprieties such as non – toxicity, ability to form film, biodegradability, biocompatibility. all this aspect as defined a wide field application: in the field of medicine, food, biotechnology, agriculture and cosmetic industry (alabaraoye e. et al. 2017). 3.2. algaelab this is a laboratory that consists of a structure for the cultivation, harvesting and drying of algae for the production of starch suitable for the production of bioplastics (fig. 2). fig. 2. algaelab (2017) at the luma atelier in arles by erik klarenbeek and maartje dros. algae bioplastics and container production through rapid printing. (www.dezeen.com/2017/12/04/dutch-designers-ericklarenbeek-maartje-dros-convert-algae-biopolymer-3dprinting-good-design-bad-world) the project algae lab won the new material award in 2018. klarenbeek & dros have set up the algae lab in collaboration with atelier luma. their project is based on the collaboration of a wide number of experts from various discipline that includes scientist of materials and designer. the definition of the new polymer is suitable to be used in the fdm technology systems, and actually the project is shifting from the small size to largest one trough a specific technological research on 3d printing system. this line of research aim at rising up the local economy and employment, giving evidenc about social inclusiveness potentiality of the project. 3.3. that’s it austeja platukyte, a student at the vilnius academy of arts, developed the project for a bioplastic produced by the addition of agar, extracted from algae, with calcium carbonate, reinforced with an emulsifying wax (fig. 3). fig. 3. that's it (2016) at the academy of arts in vilnius of arles by austeja platukyte. bioplastic based on algar and calcium carbonate reinforced with emulsifying wax. (www.austejaplatukyte.com/project-15) the produced material is lightweight and whaterproof, suitable both for packaging solution and product design, as well. after the primary use of the material it could be composted or used as fertilizer. 4. coloring the material: caffil and echinmat this section summarizes the results of the original research outcomes, conducted in the design_kind laboratory at the politecnico di bari, which led to the development of physical samples, characterized by a double composition, as they consist of the basic polymer added with food waste: it is precisely the waste that gives new perceptive qualities to the plastic material, first of all the inhomogeneity of color. the chromatic characteristics of the inclusion powders mainly affect formal variations, based on the detection of the natural colour of the organic compound used, which can be distinguished in the various samples produced. 4.1. caffil in the first case, the material produced is the result of an experiment started in the didactic and research laboratory design_kind of the politecnico di bari coordinated by the authors together with the students antonello monitillo and ivan saccotelli of the cdl in industrial design, in collaboration with crea 3d, a company specialized in 3d printing machines located in ruvo di puglia. the result is caffil, a pla filament for rapid prototyping, characterized by an internal composition with a percentage of coffee powder, resulting from the postproduction poses of bars and restaurants. the material is http://www.dezeen.com/2017/12/04/dutch-designers-eric-klarenbeek-maartje-dros-convert-algae-biopolymer-3d-printing-good-design-bad-world http://www.dezeen.com/2017/12/04/dutch-designers-eric-klarenbeek-maartje-dros-convert-algae-biopolymer-3d-printing-good-design-bad-world http://www.dezeen.com/2017/12/04/dutch-designers-eric-klarenbeek-maartje-dros-convert-algae-biopolymer-3d-printing-good-design-bad-world http://www.austejaplatukyte.com/project-15 food waste: potential bioresource for the colour of polymers 57 color culture and science journal vol. 12 (2) doi: 10.23738/ccsj.120207 100% biodegradable and compostable. the choice of the material comes from the reflection on the great quantity of food waste deriving from the bottom of coffee produced by every gastronomic activity, bar, restaurant in the italian territory, which generally does not undergo a differentiation in the waste cycle, nor a diversification for recycling. the hypothesis of reuse of this waste has been supported by the state of the art verification of other experiences of material experimentation starting from the coffee waste, including kaffeeform, decafè, c2c coffee cup, nat2 vegan, and others (fig. 4). fig. 4. examples of products made from coffee waste material. from left: kaffeeform, decafè, c2c coffee cup, nat2 vegan. what distinguishes caffil from other experimented materials is the desire to define a new material class, rather than a defined and finished product, able to open infinite creative possibilities and to generate classes of products from new material qualities. in general, coffee powder is obtained by grinding the seeds of some tropical tree species belonging to the coffea genus: although it is not a typical dyeing plant, coffee is part of the rubiacee botanical family, to which belongs, among others, the robbia, a spontaneous plant from whose roots the famous garanza lacquer was extracted. for the extrusion of the caffil filament, an italian experimental machine was used, the felfil evo, a plastic extruder capable of producing personalized filaments with a recycled base for 3d printers, starting from industrial pellets or plastic waste. the preparation of the materials involved a drying process, in an electric oven for several hours at a constant temperature of 60°c, both for the coffee grounds and for the pla pellets, in order to remove any water and humidity present. in addition, the coffee has been sieved to uniform the grain size of the compound. to extrude a filament with pla, the machine must reach a temperature of 187 °c, and then set a printing speed of 50-120 mm/s; once the temperature has been reached, the materials can be inserted in the upper pocket. the extrusion temperature affects the color and strength of the material. when the temperature exceeds 190°c, the material enters a glassy phase, which increases its fragility: with the same dosage, the material tends to behave differently between 190°c and 200°c, passing from a plastic to a glassy state, before starting to carbonize at around 210°c. even the coffee must remain roasted and must not carbonize, to avoid giving a dark color and increase the fragility of the material. in the first phase, to understand the behaviour of the composite material, different doses of the elements, different temperatures and different times were tested in order to define a stable and repeatable recipe. in fact, following some preliminary tests, to optimize the production process the machine underwent some changes, including a track with side pockets equipped with cooling fans, so as to guide the wire quickly on the winding coil. in the end, a filament with a diameter of 1.75 mm was chosen, with three different percentages of coffee compared to the pla, 8%, 10% and 20%; with this dosage different filament reels were made (fig. 5). fig. 5. caffil filament reels, 8%, 10% and 20%. the experimentation continued with the technical verification of the material following 3d printing. 4.1.1. mechanical test for the mechanical stress test, 20 dog-bone test pieces were produced (fig. 6), printed with the three different percentages of compound, according to three different extrusion directions, 0°, 45° and 90°, and different thicknesses. fig. 6. samples of 3d -printed caffil for the stress tests. food waste: potential bioresource for the colour of polymers 58 color culture and science journal vol. 12 (2) doi: 10.23738/ccsj.120207 mechanical analysis of the test pieces was carried out in accordance with the international astm d638-14 standard, which specifies the test conditions for determining the strength properties of unfilled and reinforced plastics. these properties include rupture, deformation at rupture and modulus of elasticity. the mechanical properties of plastics can change dramatically when some additives are incorporated into the formula, in particular strength and ductility. tensile strength tests were carried out in the optical test laboratory of the politecnico di bari, using an instrom uniaxial loading machine with a maximum load cell of 1 k/n. the samples were analysed maintaining a constant traction speed, corresponding to 5 mm/min, to evaluate the variation of the load supported. tensile tests have shown that the organic compound added to the pla causes a decrease in the original elasticity of the material and therefore an increase in brittleness, with acceptable values up to a maximum percentage of dust of 20% (fig. 7). fig. 7. samples dog-bone at 20%. data table: transition point from elastic to plastic deformation and breaking point. stress/strain graph tensile test. 4.1.2. optical test for the optical test, 9 square 70x70mm demonstrators were produced, printed with the three different percentages of compound and three progressive extrusion heights. in fact, to evaluate the yield of the printed filament in relation to light, the samples have a variation in thickness, one layer (0.3mm), two layers (0.6mm) and three layers (0.9mm). the test, of a subjective type, evaluated the chromatic qualities and the qualities of transparency of the material, lit directly from a natural and backlit source (fig. 8). the coffee powder is not soluble in pla, and consequently does not "dye" the plastic compound, but has a significant effect on its colour rendering. the density of the inclusion material affects the degree of brightness of the sample, which has a darker shade as the percentage of coffee powder increases and as the layer thickness increases. the particular mixture of the material gives each print a different texture, determined by an uneven distribution of the coffee in the pla and therefore in the filament. fig. 8. backlit caffil samples for optical performance. from above, proceeding in rows: coffee 8% (3 layers, 2 layers, 1 layer); coffee 10% (3 layers, 2 layers, 1 layer); coffee 20% (3 layers, 2 layers, 1 layer). in order to obtain a correspondence of the colour value of the new material with conventional colour spaces, a colour measurement was carried out on the test specimens using an ncs reader. different colour variants were detected in each sample, determined by the variegated texture of the material. therefore, it was not possible to assign a unique colour, but a palette of at least 4 different chromes. the figure 10 shows the matches of ncs values for each piece. 4.2. echinmat again, the material produced is the result of a recent experimentation carried out by the authors in the design_kind laboratory, in collaboration with some students of the cdl in industrial design, federica cardanobile and flora dell'acqua. food waste: potential bioresource for the colour of polymers 59 color culture and science journal vol. 12 (2) doi: 10.23738/ccsj.120207 fig. 9. table of ncs colour palettes corresponding to the caffil samples. the food waste adopted in this experience was chosen by evaluating the traditional consumption of fish products in the apulian territory. in particular, the sea urchin was selected for the formal quality of its shell and for its properties of reflection and chromatic variation when subjected to light radiation (fig. 10). fig. 10. sea urchin shells, chromatic variations obtained from exposure to light an analysis of the data of the coastal conservatory shows that in italian waters alone there is an annual withdrawal of about 32 million sea urchins, with an induced of about 9 million euros. however, although their shells are food waste, they are not differentiated and recovered, since the calcareous composition of calcium carbonate makes them waste of an inorganic nature, incompatible with the accelerated composting process. this aspect has encouraged the "ecological" aim of the project, which is to partially reduce waste for disposal and to return a material to the world for a second life. the sea urchin is part of the species paracentrotus lividus. the rigidity of the dermaskeleton is determined by the union of a series of limestone plates, externally characterized by a black or greenish color and purplish shades. the spines are also composed of calcite and organic matter, and have a pigment, the "chrome spine", which gives them a very intense and dark color ranging from purple to olive green, from brown to red, from yellow to black: these shades depend on the type of nutrition of the hedgehog. with the rejection of the curl, reduced to powder of different granulometry (fig. 11), polymeric binders of the epoxy and polyester types were tested to evaluate their technical and aesthetic characteristics. the use of plastic resins for the development of material samples represents a starting phase of the study, justified by practical requirements of binder availability. the choice of a variable grain size, in any case greater than 0.5 mm, has led to mould casting processes, for which a resin is used as binder (in this case pla is not suitable, because it requires a melting phase of the material at high temperatures). in a subsequent phase of experimentation, the use of bio-based matrix resins is expected, which will have a positive impact on the environmental sustainability of the new material. to date, in fact, the efforts of academic and industrial research are focused on the production of 'bio-based' polymeric materials, but currently there is little commercial availability. the bio-based nature of these materials derives from their origin from renewable and environmentally compatible raw materials, the most important of which are: starch, cellulose, lignin, furans, terpenes, natural rubber, waxes, vegetable oils, proteins. before each trial operation, the waste was carefully washed with water and ethyl alcohol to remove any organic residues and eliminate the characteristic odour: immersion in the compound for 24 hours was followed by a natural drying phase for another 24 hours. fig. 11. sea urchin shells, different particle size variations adopted in the project in order to obtain material samples, it was necessary to make moulds in which to pour the composite of curl and resin. two series of square specimens of the size 50x50x10mm were made, obtained by varying exclusively the granulometry of the compound and the type of aggregating agent: the first series was obtained by mixing food waste: potential bioresource for the colour of polymers 60 color culture and science journal vol. 12 (2) doi: 10.23738/ccsj.120207 an epoxy resin, the second a polyester resin, both transparent (figs. 12-13). fig. 12. echimat: samples with epoxy resin based on different grain sizes of the sea urchin shells. the same procedure was adopted for the production of the samples in the two series. after mixing the elements together and adding the catalyst, the compound was poured into the moulds. the main difference concerns the curing times, which are very short in the case of the polyester resin series. fig. 13. echimat: samples with polyester resin based on different grain sizes of the sea urchin shells. the tests carried out on the samples concerned the mechanical technical verification (drop test), in which the polyester samples showed greater resistance to impact, and the optical verification, through the microscopic vision of the different compounds, with a zoom of up to 10x. in this case, the polyester samples proved to be more compact and less porous than those with epoxy resin, where numerous air bubbles were visible. moreover, the composition of the polyester resin highlights more the texture obtained from the different granulometric gradients, enhancing the chromatic variations present in it. the tests therefore allowed the identification of the most suitable mixture for the final objective, the polyester resin compound, with which small demonstrators were made (fig. 14), for the final verification on moulds with more complex geometries and more dimensionally consistent. fig. 14. echimat: demonstrator 5. conclusion the paper proposes a concept referring to the color of the material through some experiments to verify the correctness of the theoretical assumptions. the scalability of the research to the industrial fields of application is open, and in this the proposed study has the limits of an experimentation conducted 'by hand'. however, on the methodological level, a description of the steps has been offered, from experimentation to technical and performance verification, in order to enable scholars in the field to replicate the process. among the expected effects, the project aims to enhance the socio-cultural context in which the history of color and the material culture to which it is associated is inserted, aiming at a redefinition of the aesthetic value "imperfect and inconsistent" of the chromatic quality of the pigment originating from the waste produced in the food and nonfood sectors of the food industry. 6. conflict of interest declaration the authors declare that nothing affected their objectivity or independence and original work. therefore, no conflict of interest exists. 7. funding source declaration this research did not receive any specific grant from founding agencies in the public or not-for profit sectors. 8. acknowledgment the contribution is the result of a common reflection of the authors; nevertheless, paragraphs 3 and 4.2 are to be attributed to a. di roma, while paragraphs 2 and 4.1 are to be attributed to a. scarcelli. 9. short biography of the authors annalisa di roma architect and phd, she is associate professor in industrial design at the polytechnic of bari (italy), specializing in design and digital manufacturing. at the centre of her research interests is the contemporary material culture of design, focused on product innovation in the context of advanced industrial standards, with a focus on the sustainability of processes, products and materials. she is the scientific coordinator of the design_kind laboratory. alessandra scarcelli architect and phd, she is a research fellow and adjunct professor of industrial design food waste: potential bioresource for the colour of polymers 61 color culture and science journal vol. 12 (2) doi: 10.23738/ccsj.120207 at the polytechnic of bari (italy). she is specialized in lighting design. the current research area combines the transversal areas of product design and information design, with particular reference to the socio-cultural aspects. references alabaraoye e., achillonu m., hester r. (2017), biopolymer (chitin) from various marine seashell wastes: isolation and characterization, springer science+bussiness media, llc ball, p. (2003) bright earth: art and the invention of color. chicago: university of chicago press. brusatin, m. (1999) storia dei colori. milano: einaudi. di roma, a. and scarcelli, a. (2017) ‘forma e colore nei modelli parametrici’, md journal, vol. 3, pp. 114-127. di roma, a., scarcelli, a. and minenna, v. (2019) ‘restoned. dalla polvere di scarto alla pietra sostenibile’, agathón, n. 5, palermo university press, pp. 183-190. falcinelli, r. (2017) cromorama. come il colore ha cambiato il nostro sguardo. milano: einaudi. ferrara, m. (2012) materiali e innovazione nel design. hoepli. kubler, g. (1976) la forma del tempo. milano: einaudi. rognoli, v. et al. (2015) ‘diy materials’, materials and design, 86 scarcelli, a. (2017) ‘il colore come elemento di progetto per una rinnovata manifattura made in puglia, a partire dalle materie prime’, in parisi, n. (ed) il parco delle eccellenze artigiane di puglia. un progetto per ginosa. bari: adda editore, pp. 57-59. food waste: potential bioresource for the colour of polymers 61 color culture and science journal vol. 13 (1) doi: 10.23738/ccsj.130207 non-invasive identification of dyed textiles by using vis-nir fors and hyperspectral imaging techniques greta peruzzi 1 , costanza cucci 1 , marcello picollo 1 , franco quercioli 2 , lorenzo stefani 1 1 istituto di fisica applicata “nello carrara” del consiglio nazionale delle ricerche (ifac-cnr), via madonna del piano 10, 50019 sesto fiorentino (fi) 2 istituto nazionale di ottica (ino-cnr), via madonna del piano 10, 50019 sesto fiorentino (fi) corresponding author: greta peruzzi (gretaperuzzi@icloud.com) abstract natural dyes have been utilized since ancient times to produce colorful garments and, at the same time, each culture has developped its own traditional designs and techniques during the centuries. hence, in order to accomplish a proper conservation program of these artefacts, it is fundamental the importance of studying the used dyes on historic textiles. traditionally, the identification is carried out through invasive or micro-invasive techniques such as hplc or raman-sers. however, a first screening using non-invasive approaches, that could tentatively identify some of the dyes in a contactless mode, is strongly reccommended. the present study focuses on the application of non-invasive spectroscopic techniques, namely fors and hyperspectral imaging in the visible and near infrared range, for the identification of dyes on textiles. twelve natural dyestuffs (twelve from plant, two insect dyes and a lichen) and three mordants (kal(so4)2, cuso4 ∙ 5h2o, feso4 ∙ 7h2o) were selected and combined to create a set of wool samples whose reflectance spectra, acquired using fors technique, were the basis for a spectral database. the same set was used to test the specim iq hyperspectral camera, with positive results for a non-invasive investigation on wider areas. the application of spectral angle mapping (sam) gave the possibility to map directly on the image pixel with similar spectral features. finally, colorimetric data were acquired with a spectrocolorimeter to obtain chromaticity coordinates. keywords natural dyes, wool fiber, fors, hyperspectral imaging, textiles, non-invasive received 17/20/2021; revised 28/03/2021; accepted 06/04/2021 non-invasive identification of dyed textiles by using vis-nir fors and hyperspectral imaging techniques 62 color culture and science journal vol. 13 (1) doi: 10.23738/ccsj.130207 1. introduction natural dyestuffs have been used since ancient times to dye fabrics and yarns to obtain colorful clothes. every culture has its own traditions, which include materials and processes of manufacturing. for this reason, in order to accomplish a complete investigation on ancient textiles it is fundamental to be able to recognize which dye has been used to understand those techniques and materials, both to pursue a proper conservation program and to discover more about the manufacturer who made the object. natural dyes can be classified according to two criteria: color or dyeing method (hofenk de graaff, roelofs and bommel, 2004; cardon, 2007). the classification based on the dyeing methods includes direct-, mordant-, and vat-dyes. direct dyes are chemical compounds, soluble in water, whose structures are full of polar groups that can bind directly to the fibers without using any other compound. mordant dyes, on the other hand, need a medium, the mordant, which is a metal salt with a chelating structure that binds the color to the fiber. some typical mordants are alum, sulphates (mainly iron or copper), stannous chloride and potassium chromate, but also tannins were used (cardon, 2007). vat dyes are chemical compounds that are not soluble in water; therefore, they must undergo a redox reaction to give the thread a color. first, the dye is dissolved in an alkaline bath where the fibers are impregnated with the soluble form of the dye and then exposed to air to oxidize and reach the final color. traditionally the possibility to make an accurate identification of dyes on archaeological and historical clothes and textiles is accomplished through invasive or micro-invasive methods. in this sense, the most used technique is high pressure liquid chromatography (hplc) (ferreira et al., 2000; rosenberg, 2008) which involves the extraction of the dye from the fiber. a more recent application to the identification of dyes is ramansers (leona, 2004), that involves the use of metal colloids to enhance the raman signal and avoid fluorescence, but that is still micro-invasive (leona, stenger and ferloni, 2006; zaffino et al., 2014; bernardino, de faria and negrón, 2015; ricci et al., 2016). nonetheless, the use of non-invasive methodologies is fundamental when working with object of artistic and cultural importance. that is the reason why a spectroscopic approach could be useful as a first screening to try to identify some of the dyes without direct contact with the analyzed object. dyeing molecules contain functional groups (chromophores) that cause color and other groups, called auxochromes, which – although not directly responsible of color – can influence the absorption of radiation and consequently make the molecule colored (mcmurry, 2012). the possibility of acquiring reflectance spectra in the ultraviolet (uv), visible (vis) and near infrared (nir), in some cases, can lead to the identification of the main spectroscopic features of each dye and to distinguish the dyes, or at least their nature (flavonoids, anthraquinones, etc.), despite all the boundary conditions that can affect the spectrum (mcmurry, 2012). in particular, fiber optics reflectance spectroscopy (fors) in the uv-vis-nir range, which has been used for the investigation of works of art since the 1990s and has become an established technique for the study of artists’ materials (bacci, 2000), represent a valid option because of its portability and ability to perform non-invasive fast in situ analysis. moreover it is reported in many recent studies, as for example (angelini et al., 2010; gulmini et al., 2013; maynez-rojas, casanova-gonzález and ruvalcaba-sil, 2017; de ferri et al., 2018; aceto et al., 2020) that this technique has shown positive results for a preliminary identification of dyes on textiles. the present study is focused to create a uv-vis-nir spectroscopic database on colored wool fibers, whose aim is to help conservation scientists and conservators – albeit in the preliminary stages of their investigation – to recognize dyes in a non-invasive way. therefore, twelve natural dyestuffs, selected among those sources of color historically used to dye textiles, and three mordants were employed to tint raw wool according to ancient recipes. data were collected in the 350-1000 nm range using fors technique. also colorimetric data were acquired using a spectrocolorimeter to calculate for each sample its chromaticity coordinates. furthermore, the application of the emerging imaging spectroscopic technique (casini et al., 2005; delaney et al., 2010; vitorino et al., 2015; cucci, delaney and picollo, 2016; blanch-perez-del-notario, saeys and lambrechts, 2019; striova, dal fovo and fontana, 2020) which combines the potentiality of spot spectroscopic with imaging techniques, made it possible to extend the fors analysis to larger areas. this was the reason for testing the specim iq (cucci et al., 2017, 2018; picollo et al., 2020) hyperspectral camera (specim, spectral imaging ltd, oulu, finland) which is compact and portable, to the same samples used to create the spectroscopic database. 2. method 2.1. preparation of samples in the present work, twelve dyes and three mordants were selected within those historically used in dyeing. non-invasive identification of dyed textiles by using vis-nir fors and hyperspectral imaging techniques 63 color culture and science journal vol. 13 (1) doi: 10.23738/ccsj.130207 among the selected dyes, nine are from plants (alkanna tinctoria, anthemis tinctoria, indigofera tinctoria, haematoxylum campechianum, rubia tinctorum, carthamus tinctorius, curcuma longa, juglans regia, reseda luteola), two are insect dyes (dactylopius coccus cacti and kerria lacca) and one is a lichen (roccella tinctoria). the preparation of samples was made by a specialist in the field following historical recipes on a set of skeins of raw wool, each of 20 g, that was prepared with three selected mordants (kal(so4)2, cuso4 ∙ 5h2o, feso4 ∙ 7h2o) to enrich the color palette. the cochineal dyed wool was etched with both alum and a mixture of alum and iron sulfate. the indigo and orchil dyes were employed with a vat procedure. the quantity of material used (% weight/weight is referred to dry material) is reported in table 1. table 1:percentage of the amount of dyeing material used referred to dry weight. the extraction of the dyes was carried out by soaking most of the plants and cochineal in water for twelve hours and then boiling the mixture for at least one hour. the alkanet dye was extracted in alcohol and the kerria lacca insect was left in a solution of water and citric acid. subsequently, the whole was filtered to obtain the bathcolor in which the skeins were soaked. some skeins were mordanted before the dyeing process using alum 25% by weight, while iron and copper sulfate (both 10%) were used simultaneously with dyes in the bath-color. the vat dyeing process was carried out for indigo and orchil. the indigo was left to ferment in a solution with 5% indigo, 5% sodium hydrosulfite, 10% soda solvay to obtain the water-soluble compound. the yarn was then soaked in the bath for twenty minutes at 55°c and subsequently exposed to air to oxidize and reach the final color. orchil dye was instead extracted by leaving the lichens in a solution of water and ammonia for one month. therefore, the dyeing process was similar to the indigo vat process. figure 1: overall of the set analyzed. samples etched with alum (a), iron sulfate (b) and copper sulfate (c), without mordant (d). 2.2. experimental colorimetric analysis were carried out using a konica minolta cm-700d spectrocolorimeter, operating in the 360740 nm range with a 10 nm wavelength pitch. the instrument features a diffraction grating, a silicon photodiode non-invasive identification of dyed textiles by using vis-nir fors and hyperspectral imaging techniques 64 color culture and science journal vol. 13 (1) doi: 10.23738/ccsj.130207 double array and a pulsed xenon lamp with uv cut filter. the measurement setup was: 8mm ø illumination area, d/8° geometry with both specular component included (sci) and excluded (sce). the colorimetric calculation was done for cie 10° standard observer and d65 illuminant. the fors data were acquired using a compact module, which is portable and features in a unique chassis two spectroanalysers equipped with fiber optics. here, it was decided to use only the zeiss mcs601 uv-nir spectroanalyser, which is equipped with a multi-channel spectrometer (mcs) polychromator with 1024 diodes, 0.8 nm spectral pixel pitch and 2.4 nm spectral resolution. the reflectance spectra were acquired in the 350-1000 nm range with 298.5 ms integration time, continuous dark current mode, and each spectrum was the average of three acquisitions to improve the s/n ratio. silica fiber optic bundles were used to send and to collect the radiation to and from the samples with a 2x45°/0° geometrical configuration to avoid the reflected specular radiation (bacci, 2000). all samples were previously analyzed using a perkin elmer lambda 1050 uv-vis-nir spectrophotometer in the 200-2500 nm range to obtain full information over the uv-vis-nir range and to understand were to focus the fors measurements. the 1000-2200 nm region was excluded from the fors measurements as it is practically covered by the wool spectral features. hyperspectral data were acquired using a specim iq hyperspectral camera, compact and portable, with an userfriendly interface, reduced weight and dimensions compared to those instruments conventionally used in hyperspectral imaging. the iq camera operates in the 4001000 nm range with a 7 nm spectral resolution. it features a cmos linear sensor with a sampling pitch of 3.5 nm for 204 spectral bands. images resolution is 512x512 pixel and data (file-cube) are almost 300mb (cucci et al., 2017, 2018). the experimental setup chosen consists of an illumination system with a fiber optic bundle and two light diffusers to send the radiation from the source (150w halogen lamp equipped with a ir cut filter) to the sampling zone, with a 2x45°/0° geometry. integration time was fixed for all measurements at 55ms, for an overall of 50s acquisition time. the ‘custom’ modality was selected to collect data, and the reference was taken using a 99% reflectance spectralon ® labsphere. calibration of wavelengths was done using a reference of orange plexiglass. furthermore, a luxmeter was employed during the data acquisition to record the amount of radiation sent over the sample, which was approximately 2000 lux, 45 mw/m 2 (almost 22.5 w/lm of uva radiation). it is important to underline that these parameters are within the recommended values of uva radiation dose for objects that are sensitive of uv-vis radiation, such as dyes and textiles. 3. results 3.1. colorimetry measurements were carried out on all samples, including those with raw wool and cardboard only. three spectra were recorded for each sample to assure repeatability and to evaluate the error for each set of measurements. in table 2 arithmetic averages are shown for both sci and sce l*a*b* (cie1976) values and their color difference, e, was obtained using the ciede2000 formula. colorimetric data show that sci and sce values are not dissimilar and that e is below the threshold of human difference color perception. 3.2. fiber optics reflectance spectroscopy (fors) for each sample, three fors measurements were acquired, positioning the bundles parallel, orthogonal and oblique to the yarn’s fibers. the three reflectance spectra compared did not show differences despite the reflectance intensity. hence, it was decide to choose the orthogonal configuration to build up the spectral database, since it showed the highest reflectance values. the comparison between spectra of wool with the three mordants highlights the influence of the metallic salts on the spectral features. in particular, wool samples etched with iron and copper sulfate show important absorptions in the uv-vis region that can affect the spectral features of dyes, making it possible to distinguish dyes not only depending on their chemical nature but also on the mordant used. through the identification of dyes of the same color emerged the impossibility to distinguish yellows (chamomile, safflower, turmeric, weld) etched with iron and copper sulfate (angelini et al., 2010). instead, it is possible to partially discern yellow dyes etched with alum (fig.2) since all samples show a wide absorption band in the 300-450 nm region, but safflower and chamomile absorb at lower wavelengths compared to turmeric and weld. moreover, weld and chamomile show a smooth shoulder at 660-670 nm. regardless, to accomplish a deep discrimination of yellow dyes it would be useful to apply statistical and multivariate procedure, such as pca (cazenobe et al., 2002). red dyes can be divided into animal and vegetal according to the n→* absorption of the anthraquinones’ carbonyl group, which occurs at 500 nm and 540 nm for madder and at 524 nm and 560 nm for cochineal and lac (gulmini et al., 2013; vitorino et al., 2015; de ferri et al., 2018). though, it is not possible to distinguish the two insect dyes except by studying their first derivative as reported in (fonseca et al., 2019) and shown in fig. 3. the identification of animal and vegetal red, instead, it is not possible with samples etched with iron and copper sulfate. non-invasive identification of dyed textiles by using vis-nir fors and hyperspectral imaging techniques 65 color culture and science journal vol. 13 (1) doi: 10.23738/ccsj.130207 table 2: ciel*a*b*1976 values and color difference (e00) between sci and sce measurements obtained with ciede2000 formula for each sample figure 2: reflectance spectra of yellow dyes etched with alum: chamomile (solid line), safflower (dash line), turmeric (dot line), weld (dash dot line). figure 3: first derivative spectra of animal red dyes: cochineal (solid line) and lac (dash line), both etched with alum. non-invasive identification of dyed textiles by using vis-nir fors and hyperspectral imaging techniques 66 color culture and science journal vol. 13 (1) doi: 10.23738/ccsj.130207 purple-bluish samples (alkanet, logwood, orchil and indigo) show reflectance spectra that make their identification possible according to values reported in literature (fig. 4). in particular it is possible to observe two bands at 424 nm and 588 nm (gulmini et al., 2013) for logwood with alum mordant and two bands at 545 nm and 580 nm (aceto et al., 2015) for the orchil dyed sample. instead the indigo dyed sample shows the typical →* absorption of the indigo molecule around 660 nm and another week band at 550 nm (monahan and kuder, 1972) and a shoulder at 345 nm (gulmini et al., 2013). the only dark dye present in the investigated set of samples (walnut) did not show any characteristic absorption. however, its spectral features in the three spectra corresponding to different mordants makes walnut dye easily distinguishable from the others in the set. figure 4: a) reflectance spectra of indigo (solid line), orchil (dash line), logwood (dot line) and alkanet (dot dash line) both etched with alum. b) reflectance spectra of logwood etched with alum (solid line), copper sulfate (dash line), iron sulfate (dot line). figure 5: reflectance spectra of indigo (a) and cochineal (b) extracted out of the file-cube using specim iq studio. 3.3. hyperspectral imaging hyperspectral data were acquired grouping samples both by hues (reds, yellows, etc.) and by the same type of dye in order to compare shades of the same dye etched with the three different salts. results show that spectra obtained with specim iq camera are comparable to those obtained with fors. indeed, for most of the samples it was possible to qualitatively identify the compound immediately after the acquisition of file-cube data. for examples, samples dyed with cochineal and indigo have the same spectroscopic features encountered in fors spectra (fig. 5). quite the opposite happens with lac and madder both etched with alum which are difficult to discriminate, since spectra extracted out from file-cubes show a wide absorption band: at 400-550 nm in the case of madder and at 500600 nm for lac. the same consideration applies to the purple-bluish dyes, especially in the case of alkanet and logwood where spectra are not well resolved. nevertheless, thanks to the use of the spectral angle mapping (sam) a b non-invasive identification of dyed textiles by using vis-nir fors and hyperspectral imaging techniques 67 color culture and science journal vol. 13 (1) doi: 10.23738/ccsj.130207 algorithm, it is possible to map directly on the image pixels with similar spectral features to recognize areas where alkanet was used rather than logwood (fig. 6). hyperspectral data of yellow dyes etched with alum show that, as predictable, it is impossible to identify dyes because all spectra extracted out from the file-cube present similar features. however, the sam algorithm permits to distinguish the four yellow dyes applying a high tolerance angle between 2.56 and 1.81 rad. figure 6: a) areal distribution of pixel with the same spectral features obtained applying sam algorithm on logwood file cube.reflectance spectra of logwood etched with alum (b) and alkanet etched with alum (c), both extracted out of the file-cube using specim iq studio. 4. conclusion results obtained in the present study constitute the basis for the creation of a spectroscopic database that will be soon online on the ifac-cnr website. the twelve dyes here analyzed represent only a starting point and it is already planned to include more dyes and typology of yarns in the future. the acquired data show convincing results for a qualitative, in situ analysis to identify dyes. fors was confirmed to be a valid technique to preliminary discern dyes according to their spectral features, being a noninvasive portable technique. finally, the specim iq camera permitted the non-invasive acquisition of imaging hyperspectral data on the set. spectra extracted out of file-cubes were comparable to those obtained with fors for most of the samples and made it possible a qualitative analysis on wider areas for each file-cube. furthermore, the application of sam algorithm permitted to map pixels with the same spectral features in order to recognize areas dyed with the same colorant. 5. conflict of interest declaration the authors state that no actual or potential conflicts of interest exist including financial, personal or other relationships with other people or organizations within three years of beginning the submitted work that could inappropriately influence, or be perceived to influence, their work. 6. funding source declaration this study was carried out without external funds. 7. aknowledgments the authors wish to thank mauro bacci, giovanni bartolozzi, andrea casini, and francesco grazzi for their helpful suggestions and discussions. a special thanks to stefano panconesi for having tinted the wool fibres and for his useful comments. a non-invasive identification of dyed textiles by using vis-nir fors and hyperspectral imaging techniques 68 color culture and science journal vol. 13 (1) doi: 10.23738/ccsj.130207 8. short biography of the authors greta peruzzi master student in conservation science at sapienza university in rome. her interests involve non-invasive investigation of archaeological and historical textiles using spectroscopic techniques. costanza cucci got her physics “laurea” and ph.d. in conservation science at the florence university. currently she is a researcher at ifac-cnr. her research focus is on spectroscopic techniques and dataprocessing algorithms applied to the fields of cultural heritage, environmental monitoring, and safety food controls. marcello picollo ph.d., is a researcher at ifac-cnr. his interests include color measurement, vis-nir hyperspectral imaging, and spot size uv-vis-ir spectroscopic investigations of 2d polychrome objects. franco quercioli is a senior researcher at the national institute of optics cnr. he is an experimental physicist whose activities have covered the fields of: coherent optics, interferometry, optical metrology, holography, fourier optics, optical engineering, confocal and nonlinear microscopy and biophotonics. lorenzo stefani is a technician in telecommunications at ifac-cnr. he is in charge of the development of hardware and software for computer-controlled instrumentation for the non-invasive and in situ study of artworks. references aceto, m. et al. 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(2016) ‘microanalysis of organic pigments in ancient textiles by surface-enhanced raman scattering on agar gel matrices’, journal of spectroscopy. edited by c. krafft, 2016, p. 1380105. doi: 10.1155/2016/1380105. rosenberg, e. (2008) ‘characterisation of historical organic dyestuffs by liquid chromatography–mass spectrometry’, analytical and bioanalytical chemistry, 391(1), pp. 33–57. doi: 10.1007/s00216-008-1977-0. striova, j., dal fovo, a. and fontana, r. (2020) ‘reflectance imaging spectroscopy in heritagescience’, la rivista del nuovo cimento, 43(10), pp. 515–566. doi: 10.1007/s40766-020-00011-6. vitorino, t. et al. (2015) ‘non-invasive identification of traditional red lake pigments in fourteenth to sixteenth centuries paintings through the use of hyperspectral imaging technique’, applied physics a, 121(3), pp. 891–901. doi: 10.1007/s00339-015-9360-4. zaffino, c. et al. (2014) ‘fourier-transform surface-enhanced raman spectroscopy (ft-sers) applied to the identification of natural dyes in textile fibers: an extractionless approach to the analysis: ft-sers for extractionless identification of natural dyes in textile fibers’, journal of raman spectroscopy, 45(3), pp. 211–218. doi: 10.1002/jrs.4443. 34 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130204 visual grouping: a study on preponderances of color or shape in match-three games joyce c. cavallini 1 , paula csillag 1 1 department of design, espm college, são paulo, brazil. joyccavallini@gmail.com, pcsillag@espm.br corresponding author: paula csillag (pcsillag@espm.br) abstract a category of entertainment that stands out for its popularity is the match-three electronic games, in which the player needs to form groups of, at least, three similar objects to score points. thus, the study of how players perceive visual groupings becomes an important tool for future developments. this research investigated color and shape relationships in match-three games, looking for preponderances in the visual grouping of color or shape in the psycho and neurological response. for this, a bibliographic and an empirical research were carried out. a beta and a final version of two match-three games, created for this research, were applied to a sample of 52 people. one of the games was black and white with different shapes, and the other, colored formed only with one shape. results of the bibliographical research indicated that the perception of visual grouping of color and shape depend on the elements with which it is interacting in the visual field, and this determines if one type of grouping will be perceived with prominence. the empirical research showed that, for the category of games studied, visual groupings of color are perceived more quickly and more easily than visual groupings of form. keywords design for games, color, form, visual grouping, match-three games. received 21/01/2021; revised 30/03/2021; accepted 14/08/2021 visual grouping: a study on preponderances of color or shape in match-three games 35 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130204 1. introduction a type of entertainment that grew with the spread of smartphones (coutinho 2014) were digital mobile games (gualà et al. 2014), and the popularization of the category of match-three games still stands out in brazil (fig. 1). fig. 1. printscreen of ranking of most downloaded casual games in brazil, from the ‘google play’ platform at 02 november 2018 [1]. for people with normal vision, the perception of visual groupings is the most important part to be observed in the mechanics of this type of game, as its dynamics is limited to making groupings of at least three similar icons by color or shape to score (fig. 2) (juul 2010). this study aimed to understand the response in relation to visual groupings of color and shape and visual comfort in the scenario of digital games of this type. fig. 2. printscreen of ‘candy crush’ game, an example of match-three game [2]. 1.1. visual grouping in psychology and visual language visual perception is defined in modern psychology as an active combination of sensorially received stimuli and organic interpretation, which organizes and relates them to previous experiences (dondis 2007). arnheim (2008) affirms that visual groupings can be perceived by similarity, proximity, clarity, configuration, direction, speed, consistency (regular, homogeneous) and contiguity (merged forms that are seen as unique). the author indicates that color and shape belong to the same grouping perception, the similarity one. he highlights that depending on how the objects are related in the visual field, they will be seen more or less united: “a visual object is all the more unitary the more closely its elements are in factors such as color, clarity, speed and direction of movement.” (arnheim 2008, pp. 79) visual grouping: a study on preponderances of color or shape in match-three games 36 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130204 kepes (1944) determines that a visual grouping can be perceived through two factors: similarity due to the object's own quality or proximity. this author affirms that similarity groups appear to be perceived as more unified than groups formed by proximity. for dondis (2007), in contrast, proximity is more important than similarity. the three authors, anheim (2008), dondis (2007) and kepes (1944) place color and shape as characteristics belonging to the same type of visual grouping, which is similarity. 1.2. visual grouping on neurologic studies for neuroscience, the difference in the perception of color and shape clusters directly depends on the way the brain perceives, processes and relates these two types of visual stimuli. several studies debate whether color and shape are perceived in different regions of the brain or whether they are processed by the same group of neurons. this affects the understanding of speed and the way visual information is perceived (aymoz and viviani 2001). in an experiment carried out by moutoussis and zeki (1997 apud rentzeperis et al. 2014), the authors understand that different visual attributes presented at the same time may not be perceived simultaneously, which would indicate different ways of processing. the moutoussis and zeki ‘color and form experiment’ consisted of presenting a screen to some participants, half of which was colored with a checkerboard pattern that alternated between red and green, and the other half with gray bars alternating the inclination from left to right. fig. 3. the ‘color and form experiment’ of moutoussis and zeki from ‘functional segregation and temporal hierarchy of the visual perceptive systems (1997)’. the participants had to combine the colors of the squares with the orientation of the bars that were presented simultaneously. the changes in color and orientation occurred in the same proportion, presented at various phase differences (0-360º, varied in steps of 10º, randomly). for some of these differences, the sensed color and form values were different from the real ones. the temporal disparity then indicated that colors were perceived approximately 63 milliseconds before form (moutoussis and zeki 1997). in another experiment, aymoz and viviani (2001), tested 20 students at the university of geneva with normal vision. participants were located 50 cm from a computer monitor and had their responses to stimuli monitored by a standard graphics program. the experiment investigated the processing of three visual attributes: color, shape and movement. there were three conditions, one for each possible pairing of these attributes. stimuli were combinations of two values for each attribute (red / green, circle / square, fixed / mobile). in each condition, the stimuli changed twice quickly, each attribute changing asynchronously between the two possible values. the participant should inform which change he perceives first (aymoz and viviani 2001). fig. 4. aymoz and viviani experiments (2001). timing of the events within trials. a1 and a2 (b1 and b2) are the two possible values of the stimulus attributes a and b. in this example, the initial stimulus (a2b2) lasts for 1 s, changes into the intermediate stimulus (a1b2) which lasts for δ ms (soa), and is finally transformed into the final stimulus (a1b1) which lasts 1 s. with the experiment, they computed 13 values of asynchrony, and transformed them into estimates of perceived time. the results showed that color and shape are processed almost simultaneously, and the perception of movement is delayed by about 50 milliseconds (aymoz and viviani 2001). visual grouping: a study on preponderances of color or shape in match-three games 37 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130204 clifford et al. (2003 apud rentzeperis et al. 2014) tested the perception of color and orientation using sinusoidal gratings oscillating in color and orientation at the same time frequency and for a series of phase differences. they discovered that, depending on the speed of presentation of the forms, the asynchrony of perception changed. fig. 5. clifford et al. (2003) experiment at an oscillation period of 600 ms as a function of the relative phase of oscillation (ϕ). it was found that for faster presentation rates, color and orientation were perceived at the same time, however, as the frequency of presentation decreased, the asynchrony between color and orientation increased. in the 1 hz presentation, color perception preceded orientation in 50 milliseconds. to explain the difference in perception in the two different contexts, rosenholtz et al. (2012 apud rentzeperis et al. 2014) propose a psychophysical model in which, depending on the target object of the vision, the vision system considers or disregards the rest of the visual plane, whether the eyes are looking for something in the scene or just following a target and disregarding the rest. this disregard is closely linked to the locations in the brain where information will be processed. it can be processed together (color and shape), which would mean the same preponderance in the cognitive response, or processed separately, which would cause a difference in processing time. thus, studies move towards the understanding that, depending on the context and the relationships involved, neurons work in different ways (parallel or serial) and in different brain locations. thus it is possible to state only that, depending on the interaction, different preponderances between color or shape will be noticed in the visual grouping. 2. empirical research to understand the relationship of preponderance in visual groupings of color and shape in match-three games, two games and a qualitative questionnaire were developed by the authors to test the speed with which players group similar sets. one of the games applied was black and white, with welldefined shapes (square, circle, rhombus and triangle). the other was polychromatic (multiple hues), with only one shape (circles) of pure rgb hues (yellow, blue, red and green), with the same brightness and saturation. the games and the questionnaire were applied to a sample of 52 people, between 18 and 30 years old, attending higher education at espm college in são paulo, brazil. female and male individuals were tested, equally divided into 2 groups, with each group containing 26 people. the selected subjects claimed not to have color blindness or any other compromising chromatic pathology. the tests had a determined order of application, half of the tested people started playing the first, the other half the second game, so that the learning of the mechanics did not influence the speed of resolution of the objectives. each group of 26 was divided into two new groups of 13 people, who alternated the game initially tested (13 started with game 1, the rest with game 2). the average resolution speed of each game was compared in order to understand possible preponderances in the cognitive response of color and shape grouping. before the final tests, a beta test was carried out to detect aspects that could be improved. regarding the application of the tests and methodology, the sample used was 12 people, 6 males and 6 females. a qualitative questionnaire for data collection was carried out at the end of each test. it asked the name of the individual for further identification of the data, age, biological sex and the following questions:  which one of the two games, black and white or color, did you find easier to group? why?  which of the two games did you find most pleasing to see? why?  did you notice anything different in the way you perceived the groupings in the two games?  do you have any observations or suggestions? if so, which one? 3. game development the games were programmed on the game engine ‘unity 3d’, with the aid of a basic free code for match-three game from the blog dimitris-ilias gkanatsios [3]. a visual grouping: a study on preponderances of color or shape in match-three games 38 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130204 programmer (mario sérgio affonso junior) was hired to assist in the preparation of the two games. the visual part of the games was developed with the adobe illustrator vector image program. both games work the same way, having the same programming code, just changing the visual part, ensuring that the two tests had the same level of complexity. at the end of each game, the game program automatically generates a report informing the number of groupings made, name and time in order to better organize the information collected. the groupings that are considered in the report are those of moves made manually, that is, formations that occur in a chain are not counted. both games have a black background and differ from other games in the market that have complex and/or textured backgrounds. however, this form of presentation was chosen to isolate the object of this research, in this case, the color and shape groups, without distractions. for the empirical test, the authors intended to create greater contrast between figure and background. according to csillag (2015), light colors are perceived prominently in contrast to a black background. this way, it was decided to use figures with 100% brightness on a black background. for the black and white game, four basic shapes were chosen: square, rhombus, circle and triangle. the square had reduced height in comparison to the other geometric shapes in order to appear the same amount of empty area around it, guaranteeing the perception of individuality when close to other squares. thus, as previously explained, it is also possible to form visual groupings by proximity of items but the objective of our study is the grouping by similarity. both the colored and the black and white game have 100% brightness of their items and a black background (r = 0 g = 0 b = 0; # 000000), in order to obtain equivalent contrasts. both games have a home screen where information about the participants is given, such as name, biological gender and the option of the game being colored or monochrome. after selecting one of the games to play (previously determined), a preparation screen will appear for the player, with the intention of allowing the player to decide when to start the game. the two games have a 30-second timer on the upper portion of the screen (fig. 4 and 5), indicating the time remaining to group the largest possible number of similars. the stopwatch was implemented as the limiting mechanic of these games. fig. 6. printscreen of the colorful game designed by the authors. fig. 7. printscreen of the black and white game designed by the authors. after the 30 seconds of the stopwatch, a game over screen will appear indicating the end of time, with the possibility of returning to the home menu and starting the other game. 4. beta test a beta-test was carried out, before the final tests, in order to check if there was a need for adjustment in both games and in the questionnaire. it was found that the visual groupings of color (125 combinations in total) were better perceived by users compared to those of shapes (91 combinations in total). nuisances with the saturation of the colored game have been described by the players, however the modification of this parameter was not perceived relevant, because despite the discomfort, the results indicated that the perception of visual groupings by color remained visual grouping: a study on preponderances of color or shape in match-three games 39 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130204 prevalent. instead of discomfort, other players described that the saturated color becomes important for a good differentiation of the hues. the beta test revealed that the “game over” screen caused a negative feeling in the players, therefore, the red “game over” was replaced by “end of the test”. with this change, this bad feeling, which could change the test results subsequent to the first game, was overcome. 5. final tests at the beginning of the test, respondents were asked if they had any type of pathology that compromised their visual understanding of color or shape. in addition, permission to collect data was requested by completing two copies of a consent form. after that, a brief explanation of how the tests worked and how to perform the combinations in the game was given. at the end of the test with the games, the qualitative questionnaire was administered through google forms. the final games found that visual color groups were perceived more quickly by players, as soon as the programs accounted for a total of 644 color grouping and 435 form grouping made by the participants. these results were made up of 47 people (90%) who make more color groups than form, 3 females and 1 male (8%) who made more combinations by shape than by color, and 1 female (2%) who made equal combinations in games of color and shape. a little difference was noted between the number of combinations made by male and female players in both games. in the color game the male respondents made 333 combinations, while the female respondents made 311. in the black and white game, the male respondents made 221 combinations and the female 214. it may be concluded that, even though male participants had made more combinations, the preponderance in combinations of the colorful game is perceived, in both sexes. the qualitative questionnaire based on the players perception also demonstrated greater facility and comfort to make colored groups. for the question: “which one of the two games, black and white or color, did you find it easier to group? why?”, 90% of respondents (47 people) replied that they preferred colored groups, 8% shaped ones (4 people) and 2% (1 person) presented an incongruous answer. for people who responded that they had a preference for colored groupings, the following aspects were highlighted: greater visuality, more visible the groupings, ease of grouping, easy assimilation, more agile, more attractive, forms not sufficient to integrate the player and the game, and greater emphasis in perception. for people who responded that they preferred shape groupings, the following aspects were highlighted: shapes are easier to differentiate, shapes help to group, more pleasant to play with less intensity than color and colors cause confusion. for the question: “which one of the two games did you find most pleasing to the eye? why?”, 79% of those surveyed (41 people) replied that they preferred the colored game, 21% the form game (11 people). it was highlighted that for the color test: there is more familiarity in playing colorful games, it is easier to understand the possible combinations, you can better identify the colors, the homogeneous shapes and saturated colors help, it is better to see, livelier and happy, better mental organization, there is greater visibility, more homogeneous space between shapes, it is more intuitive, more attractive, more flashy and inviting, because it is colorful it is more beautiful, the shapes were not enough to cause ‘integration’ with the game, greater differentiation and visualization, the black and white game it is more confusing and difficult to concentrate, color highlights the vision more, ‘it hurts’ less the eyes, greater similarity in the grouping, less effort to group, in the form everything is mixed. for the black and white test, the highlight was: the colored game confuses the vision, which is more pleasant, which caused relaxation and making the test less intense, personal preference for black and white, too saturated colors, more aesthetically pleasing, in the color game, the contrasts were unpleasant. for the questions: ‘did you notice anything different in the way you perceived the groupings in the two games?’ and ‘do you have any observations or suggestions? if so, which one?’, not all participants had observations to make, the observations made stand out from the points already presented, as shown below. in the black and white game: a 20 years old (20 y.) male (m) needed greater concentration to find the combinations. a 20 years old (20 y.) female (f) person noticed that she made combinations from the tips of the shapes and thinks that she did not make many combinations with the circles. a player (m, 19 y.) said that everything is perceived as a unique visual mass. another player (f, 22 y.) ‘fright’ when the white shapes appear. other one (f, 22 y.) took a long time to "understand" the shapes. visual grouping: a study on preponderances of color or shape in match-three games 40 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130204 in the color game: a person (f, 18 y.) said finding the blue circle was easier. other one (m, 21 y.) saw the feedback of groupings was more visible. a player (m, 18 y.) used the intensity of the colors to form combinations. other one (f, 22 y.) felt easier to play with equal shapes. another (m, 21 y.) thought that perceiving colors is more natural than thinking about which shapes are identical. a participant (m, 19 y.) said that he managed to form “color spots” that facilitated the game. overall: one player (f, 21 y.) found the tests very fast and other one (m, 19 y.) thought it would be beneficial for the game to combine colors with shapes. 6. final considerations the previously cited visual language and psychologic studies of arnheim (2008), dondis (2007) and kepes (1944), show that color and form belong to the similarity aspect of visual groupings, and the greater the resemblance, the greater the perception of grouping. in addition, the previously cited neurologic studies of aymoz and viviani (2001), clifford et al. (2003 apud rentzeperis et al. 2014), moutoussis, k. and zeki, s. (1997) and rosenholtz et al. (2012 apud rentzeperis et al. 2014), show that sometimes color and form are perceived without prominence; sometimes color is perceived before, and for lower exibittion rates, color is perceived before form. it may be concluded that the visual grouping of color and shape are perceived in different ways depending on the context in which they are inserted. with the results obtained from our empirical research, it may be concluded that the factor that facilitates the speed of visual grouping in a match-three game is the use of different colors (hues) in the game icons. this study demonstrates that for visual groupings of color and shape in match-three games, color is predominantly seen as a factor of better and faster assimilation of groupings. most respondents also report greater comfort when playing the color test. based on this, developers are recommended to use color and shape combinations in their projects when differentiation is necessary. this will help differentiate objects by different and highly contrasting hues, as the user's response is quicker and easier for color combinations. such differentiation can benefit the experience and user interface (ux and ui), making the action or gameplay more comfortable and intuitive. 7. conflict of interest declaration the authors declare that there is no conflict of interest regarding the publication of this paper. 8. funding source declaration this research was financially supported by espm college, from 2018 to 2019, by the iniciação científica program (pic). the financial support allowed full study dedication. 9. short biography of the author(s) joyce c. cavallini – graduated in design at espm college. paula csillag – professor doctor at espm college, since 1999, lecturing in the design department. research interests are related to color communication, visual language, color perception and color trends. notes [1] printscreen taken at the ranking of most downloades casual games in brazil at november 2018, available at: https://play.google.com/store. (acessed: 02 november 2018). [2] printscreen taken at a stage of candy crush saga at november 2018, available at: https://play.google.com/store/apps/details?id=com.king.candycrushsaga . (acessed: 02 november 2018). [3] complete tutorial by gkanatsios, d. (2015) of how to building a match-3 game (like candy crush) in unity. available at: https://dgkanatsios.com/2015/02/25/building-a-match-3-game-in-unity3/. (acessed: 25 april 2018). references arnheim, r. (2008) ‘arte e percepção visual: uma psicologia da visão criadora’. 1st edn. são paulo: cengage learning. aymoz, c. and viviani, p. (2001) ‘colour, form, and movement are not perceived simultaneously’. university of geneva, uhsr university, geneva, milan. doi: 10.1016/s0042-6989(01)00160-2. clifford, c. w., arnold, d. h. and pearson, j. (2003) ‘a paradox of temporal perception revealed by astimulus oscillating in colour and orientation’. coutinho, g. l. (2014) ‘a era dos smartphones: um estudo exploratório sobre o uso dos smartphones no brasil.’ universidade de brasília, unb, brasília. csillag, p. (2015) ‘comunicação com cores: uma abordagem científica pela percepção visual’. ed. são paulo: senai-sp. dondis, d. a. (2007) ‘sintaxe da linguagem visual’. 3rd edn. são paulo: martins fontes. visual grouping: a study on preponderances of color or shape in match-three games 41 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130204 gualà, l., leucci, s. and natale, e. (2014) ‘bejeweled, candy crush and other match-three games are (np-) hard’. università degli studi di roma tor vergata, roma. doi: 10.1109/cig.2014.6932866. juul, j. (2010) ‘a casual revolution: reinventing video games and their players’. cambridge, ma: mit press. kepes, g. (1944) ‘language of vision: painting, photography, advertising-design’. 13th edn. chicago: paul theobald and company, pp.46-48. moutoussis, k. and zeki, s. (1997) ‘functional segregation and temporal hierarchy of the visual perceptive systems’. department of cognitive neurology, university college london, london. doi: 10.1098/rspb.1997.0196 rentzeperis, i., nikolaev, a. r., kiper, d. c. and leeuwen, c. v. (2014) ‘distributed processing of color and form in the visual cortex’. university of zürich and swiss federal institute of technology, zürich. doi: 10.3389/fpsyg.2014.00932 123 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140115 colour measurement and documentation in historical buildings: the case study of the kirna manor house in estonia claudia valge1, sofia ceccarelli2, silvia bertacchi3, andres uueni1, hilkka hiiop1, anneli randla1, fabrizio ivan apollonio3 1 dept. of cultural heritage and conservation, estonian academy of arts, tallinn, estonia, claudia.valge@artun.ee, andres.uueni@artun.ee, hilkka.hiiop@artun.ee, anneli.randla@artun.ee 2 dept. of industrial engineering, university of rome tor vergata, rome, italy, sofia.ceccarelli@uniroma2.it 3 dept. of architecture, alma mater studiorum university of bologna, bologna, italy, silvia.bertacchi@unibo.it corresponding author: sofia ceccarelli (sofia.ceccarelli@uniroma2.it ) abstract historical buildings and their decorative apparatus have a key role in the transmission of national and local traditions, requiring careful conservation of these structures and their overlapping decorative layers, mostly made up of stuccos and coatings. unfortunately, the procedures and methodologies for both documenting and preserving such cultural heritage are not clearly standardised in estonia, where most historic manor houses are managed by private owners who have no precise guidelines to follow during the restoration of such complex structures. to amend this issue, the estonian academy of arts (eka) organised an international workshop on “colour measurement and documentation in architectural paint research” with the aim to bring together several experts, techniques and tools from different countries in order to define, optimise and modernise the methodologies employed for the identification, documentation and preservation of historical painted interiors and colours. in addition to a theoretical session, the workshop held in october 2019 entailed practical work at the kirna manor house, analysing the entrance hall of the building. the paper presents the results of the research and the discussion between international experts. keywords colour measurement, colour documentation, colour vision, architectural paint research, historical interior restoration, estonian manor house, estonian academy of arts received 17/05/2021; revised 27/09/2021; accepted 05/04/2022 colour measurement and documentation in historical buildings: the case study of the kirna manor house in estonia 124 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140115 1. introduction the conservation of historical buildings and their ornaments is paramount for preserving national and local architectural traditions. within this context, understanding the perception of colours and their use on original building decor constitutes a research topic which is relatively understudied. furthermore, in many countries, including estonia, the guidelines for standard procedures for colour determination and documentation in architectural paint research are not entirely clear or even unavailable. nowadays in estonia, as in several other countries, visual comparison using colour charts/fan decks is the main approach for colour determination in architectural frameworks. the current regulations set by the national heritage board of estonia recommend studying colours using this method, without the mention of scientific measurement devices (appendix to the heritage conservation act, 2019). the multitude of methods and the lack of specific instructions cause confusion among researchers, conservators and building owners, as the possibility of subjectivity leading to inaccurate colour determination remains. in order to improve this issue, the estonian academy of arts (eka) organised an international workshop “colour measurement and documentation in architectural paint research”, held in tallinn (estonia) on october 22–25, 2019. conservators, art historians, specialists in colorimetry and digital reconstruction involved in paint research and conservation from 6 countries gathered to share expertise and gain international consensus on documenting, interpreting and visualising the colour information of historical buildings. the workshop was organised in two parts: the first was a theoretical session with keynote lectures about the best practices in participating countries followed by a discussion; the second part was practical and carried out in situ in the historical interior of the kirna manor house (in järva county, ca 100 km from tallinn, estonia). in the latter part, research teams were formed and assigned leaders who developed workflows for the identification of historical colour schemes, colour measurement and documentation. for the data acquisition, several systems were used, e.g. colorimeters, a spectrophotometer, colour charts and digital photographic equipment. the use of various techniques allowed participants to learn from international expertise, compare different methodologies and eventually discuss how to optimise and modernise the identification, documentation and preservation of historical colour information on architectural surfaces in estonia and abroad (carbonell rivera, montalvá españa and lerma garcía, 2016; giannattasio, 2019; guarneri et al., 2019; verweij, schade and kutzke, 2019). simultaneously with the paint research, a colour vision experiment was conducted with the workshop participants to test the accuracy of human colour perception. in the final roundtable discussion, practical solutions were suggested, which could be developed into a pipeline including both scientific measurements and historical/visual evaluations. 2. aims of the workshop the purposes of the workshop were: 1) to experiment with various paint research methods on the finishes of the entrance hall’s vaults and their adjacent architectural features; 2) to test both destructive and non-destructive colour measuring techniques and tools; 3) to identify and date the paint layer stratigraphy, colour schemes, and the ambiguous constructional stages and additions in the hall; 4) to revise the adopted workflow and define the best practice in light of the workshop results. the practical investigation was organised in five teams, each led by an international expert who instructed their team members according to the prevalent architectural paint research methods in their respective country. the results were documented separately by each team in the form of reports and paint exposure charts compiled by a student of the department of cultural heritage and conservation (valge et al., 2020). finally, the teams engaged in constructive interaction, comparing their results to share reflections and proposals for research improvement. 2.1. historical overview of the kirna manor house the kirna manor estate and the first wooden manor house were established in the 17th century by the baltic german nobleman hans von fersen, whose family would keep ruling the estate for nearly 150 years (maiste, 1985). the existing neo-palladian building was probably erected between 1760 and 1780 by otto wilhelm von fersen, with neo-classical alterations having been made in the early 1800s by the new owner carl magnus von der osten-sacken (danil et al., 1985; parek, 1973). gothic revival elements were added to the building in the mid-to-late 19th century when the manor belonged to the pilar von pilchau family. the manor estate has a long history of owners, uses and renovations, which is why many overlapping layers of architectural and decorative details and their finishes have been preserved. the investigation was focussed on the central entrance hall of the building (fig. 1), which has been extensively modified throughout centuries. colour measurement and documentation in historical buildings: the case study of the kirna manor house in estonia 125 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140115 fig. 1. the entrance hall of the kirna manor house, järva county, estonia (https://www.puhkaeestis.ee/et/kirnamois ). 3. experimental methodology the experimental part of the workshop consisted of: 1) general research documentation; 2) identification and dating of layers under the current finishes; 3) characterisation of the pigments and components used in the plasters and finishes; 4) colour measurements on the preserved paint layers; 5) an experiment for testing the accuracy of human colour vision. 3.1. general documentation the documentation has been carried out mainly producing drawings/notes and photographic material before, during and after destructive exposures and samples. data gathering dealt with capturing digital images with different devices (smartphones, compact cameras, dslrs), adding a ruler for size reference and an x-rite colorchecker classic/ passport photo 2 for colour reference. one team experimented with a more detailed system for storing image metadata and best quality data such as 1) shooting in raw format to gather uncompressed data, 2) converting images into lossless compressed formats, 3) processing images, balancing colour and storing useful data for further digital processing (gaiani et al., 2016; ramanath et al., 2005). 3.2. analysis of hidden layers the study of the complex chromatic stratigraphy of the entrance hall was firstly analysed examining the existing photographic material starting from the early 20th century, which, albeit mostly in black-and-white (fig. 2), helped to clarify some historical decoration stages and colour schemes. secondly, small mechanical paint exposures were conducted in strategic areas (i.e. where colour changes were detected in historical images), such as walls, pillars and pilasters, window and door openings, the stucco decor on the vaults. although the latter is a relatively destructive technique, paint exposures proved essential in discovering previous decorative phases and paint colours. the revealed layers were identified with a shared indication system, numbered in chronological order starting from the oldest and compared in various areas to verify the layer order and chromo-chronology (fig. 3). fig. 2. one of the earliest photos of the entrance hall, ca 1910 (estonian national museum, https://www.muis.ee/museaalview/666779). fig. 3. a paint exposure with the finishes chronologically numbered. https://www.puhkaeestis.ee/et/kirna-mois https://www.puhkaeestis.ee/et/kirna-mois colour measurement and documentation in historical buildings: the case study of the kirna manor house in estonia 126 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140115 3.3. analysis of hidden layers in addition to on-sight evaluations of the paint ingredients, paint cross-sections detached with scalpels were examined in the laboratory under a microscope under visible and ultraviolet light, and scanned with an electron microscope (sem), which enabled to correctly identify the paint stratigraphy and some pigments (fig. 4). fig. 4. the sem analysis detected the presence of copper and zinc in a metallic paint layer uncovered on the decorative piping on the vault arch edges, which implies it is brass paint or gilding. 3.4. colour determination different approaches were used for the colour determination in the entrance hall: a) colour measuring devices; b) image and colour processing software; c) naked eye perception which was mostly assisted by specific colour charts. the paint layers were examined using both daylight and controlled flicker-free artificial led-lighting (yongnou digital yn1200, cri>95+) given their indoor location. a) the portable tools used for measuring colours were a konica minolta spectrophotometer (cm 2300d) and colorimeters ncs colourpin se and ncs colour scan 1.0 (rm200). the systems use two different measurements methods: the spectrophotometer provides a spectral response of the colour to light stimulation, translated into physical colour space coordinates, cie l*a*b* in this case, the operating range of wavelengths of the spectrophotometer is between 360 nm to 740 nm. this type of instrumentation is often used for quick analysis in situ or when moving an artwork is impossible (sanderson, 2015; ceccarelli et al., 2021). the colorimeters give a direct translation into the closest ncs notation and index (perceptive colour) along with related cmyk, rgb, l*a*b*; meaning that it represents the closest match to an existing colour in the ncs chart with its coded name (kahu et al., 2018). b) various pipelines have been developed by researchers for balancing captured images and specific software can be used to process images for documenting colours (rieger et al., 2016; gaiani and ballabeni, 2018). e.g., adobe camera raw allows white balancing images captured with the colour reference x-rite colorchecker classic or portable; profilemaker professional 5.0 can be used to create an icc profile assigned to the images; imatest master 5.2.4 allows testing the colour fidelity between the reference colorchecker patch and its radiometrically calibrated image in terms of the mean camera chroma relative to the mean ideal chroma in the cie colour metric (δe*ab) to estimate perceptibility tolerance of colour quality (mokrzycki et al., 2011; gaiani et al., 2019); c) visual colour determination using side-by-side comparison with colour charts/fan decks helped to define the closest colours to the historical paints. although much more accessible and affordable than colour measurement tools, this vision-based technique is reliant on the researcher’s individual colour perception, colour differentiation expertise, lighting conditions and other factors. the colour charts used were the ncs natural colour system index 1950 colour chart; the ncs colour chart kulturkulör för linoljefärg, developed in collaboration with the swedish national heritage board, which contains 300 colour samples with traditional pigments historically used in linseed-oil paint; and the caparol 3d system plus, a more affordable colour chart with a limited selection of samples which resemble historical colours. alternatively to the use of colour charts, some experts mix a similar colour to the historical paint on site for illustrating it in research documentation, which, however, lacks standard classification. 3.5. colour vision experiment in the first part of the experiment, the 27 test subjects were asked to describe and determine the colour of two different historical paint layers uncovered on a window scuncheon in two lighting conditions (daylight and spotlight, see fig. 5) using the ncs index 1950 colour chart. later, the colours were measured with the colorimeters ncs colourpin se and ncs colour scan 1.0 rm200, as well as the konica minolta spectrophotometer cm 2300d. in the second part, the test subjects took the colour blindness test developed by jean jouannic and the x-rite hue test online (see references) to evaluate their general colour perception and the ability to differentiate similar hues. finally, the results of the colour vision tests were compared with the colour determination experiment to evaluate the potential correlation. colour measurement and documentation in historical buildings: the case study of the kirna manor house in estonia 127 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140115 fig. 5. the participants determining the colours of the paint patches in a) daylight and b) under a spotlight. 4. results 4.1. architectural paint analysis during the two-day paint investigation, at least eight historical colour schemes (fig. 6) were discovered in the entrance hall. the earliest pastel scheme probably dates from the neo-palladian remodelling conducted shortly after 1804. another important discovery was that the pointed groin vaults of the room are an essential structure erected simultaneously with the late 18th-c building rather than a decorative form added during the gothic revival period. meanwhile, the plastered surfaces as well as the stucco decor probably date from the early 19th-c neopalladian modernisation of the building. judging by the paint stratigraphy, the later added pointed doors and windows most likely originate from the mid-to-late 19th century. nevertheless, due to the limited time of the workshop, all preliminary findings presented in this section need to be confirmed and elaborated on with further research. fig. 6. visualisation of two relatively recent colour schemes illustrated with the ncs values acquired on the exposures: a) ca 1960s; b) current state of the room. 4.2. outcomes of the colour vision test 19 out of 27 test subjects determined colour matches which were noticeably dissimilar with the most common results of the ncs colour chart determination and colour measurement devices. the colour measurements carried out with three instruments were relatively similar yet visually differentiable, which implies that colorimetric results do not only vary across devices but are also heavily dependent on the specific measuring area. the two spectrophotometer results for the first dark green colour were also identified by the participants in 14 instances (fig. 7a). meanwhile, none of the colorimetric results coincided with each other nor with the colour codes determined by the participants for the second lighter yellowish colour (fig. 7b). however, the same ncs notation was identified by the test subjects in 24 instances out of 50. this suggests that while human colour vision is fallible and varies, it is still surprisingly similar considering how the results of precise colour measurement devices also differ. another observation was that participants found it more difficult to identify the darker colour in insufficient natural light, which means ample lighting is paramount for more accurate visual colour determination. fig. 7. the results of the colour measurement devices and the most common ncs matches determined by the test subjects for a) the first dark green colour and b) the second lighter yellowish colour. all but a few test subjects had faultless results in the jouannic test for general colour blindness while slightly less than half made a few mistakes in the x-rite hue test. most commonly, the test subjects had colour vision issues in the turquoise/green area of the spectrum. these results are consistent with the most common form colour measurement and documentation in historical buildings: the case study of the kirna manor house in estonia 128 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140115 of colour blindness, deuteranomaly (reduced sensitivity to green light; a milder form of deuteranopia, commonly known as daltonism) which effects 5% of males and 0.4% of females (kalloniatis et al., 2007). the fact that the results for the green colour varied much more also validated the hypothesis that it would be more difficult to ascertain the green colour than the yellowish one. this reflects the studies which have shown that colour blind people mostly retain blue–yellow discrimination, and most colour-blind individuals have limited discrimination along the red–green axis of colour space, with their ability to separate colours in this dimension being reduced (sembulingam et al., 2012). 4.3. colour measurement devices versus visual comparison colour measurement devices enable to quickly and very accurately ascertain colour, although the results can still be dependent on lighting. however, since the historical paint on architectural surfaces is mostly unsmooth, faded, discoloured or cracked, the precision of the measurements depends far more on the measured spot than the specific device used. with instruments like the ncs colourpin se it is very difficult to locate an ideal measuring spot due to the lack of a viewing port. the human eye is hence a more precise tool for determining the exact area where the paint is most vibrantly (accurately) preserved. moreover, while the colour measuring devices can only focus on a very small surface area at a time, our eyes can generalize, evening out the patchy colour of the historical paint surface more adequately. this skill is especially useful for identifying the colours of less opaque paint layers, which have previous layers showing through. regardless, visual colour determination is still extremely dependent on surrounding lighting, personal colour perception and colour differentiation experience as the results of this experiment clearly showcase. furthermore, commercial fan decks can be unsustainable due to being discontinued, and the inferior convertibility of the results. on the other hand, although the l*a*b* spectral data received with a spectrophotometer allows to preserve the most accurate and reproducible information about historical paint colours. in conservation practice (e.g. repainting) it is still usually necessary to convert this data into commercially used colour systems like ncs, which potentially causes slight conversion inaccuracies as seen in fig. 8, which summarizes the colorimetric data acquired in several points. however, colour charts also have a limited selection of colours, allowing room for imprecision. still, they are accessible and cost-effective tools for most paint researchers, whereas spectrophotometers can be too costly and require consistent maintenance and re-calibration. fig. 8. ncs and cie l*a*b* coordinates for the 5 paint layers of an exposure. 5. conclusions the workshop was a successful first attempt at determining the correlation and the differences between colour measurements obtained with visual, digital and spectrophotometric analyses. additionally, the interdisciplinarity of the workshop participants provided a diversified viewpoint on the subject matter as well as reaching novel and insightful perspectives through international collaboration and expertise. the debate about the pros and cons of various colour measurement and documentation techniques and methodologies is not only applicable to this case study but also generally to the usual workflow adopted by experts with limited time and budget for paint research prior to restoration. the workshop also yielded tangible results in the architectural paint investigation carried out in the kirna manor house entrance hall, where many historical colour schemes were discovered. in general, it should be taken into account that there is no absolute truth in determining the colour of historical paint due to it having been discoloured through time to begin with (see e.g. krotzer, 2008, van velzen, 2018). however, it would be beneficial to implement precise colour measurement devices in architectural paint research more often, while acknowledging that it still requires a trained eye and good colour perception to see where to take the measurements from. still, they are accessible and cost-effective tools for most paint researchers, whereas spectrophotometers can be too costly and require consistent maintenance and recalibration. the use of portable and quick-capturing colorimeters could easily be adopted by researchers without excessive costs or added expertise. colour charts also remain essential tools because they display painted colours much more realistically than digital screens, thus enabling to directly compare a physical colour sample with the painted architectural surface. even though colorimetric tools are more accurate than the average human eye, colour charts remain useful for cross-checking the results in situ. colour measurement and documentation in historical buildings: the case study of the kirna manor house in estonia 129 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140115 colour measurement devices enable to improve the speed and accuracy of colour measuring and obtain more objective and reproducible data, which can easily be preserved in online databases for subsequent indepth analysis. ultimately, visual colour identification and the use of colorimetric instruments are complementary methods which should be utilised in parallel to receive the most comprehensive and accurate results. the results of the workshop are now used in the department of cultural heritage and conservation at the estonian academy of arts for the development of a digital documentation system related to colour data collecting and presentation, with the aim of its future application to the restoration of other estonian historical buildings and potentially also to international case studies. 6. conflict of interest declaration authors declare no conflict of interest. 7. funding source declaration funding of the workshop was provided by the estonian academy of arts and the european regional development fund. 8. acknowledgment the authors would like to thank the estonian academy of arts, the organising committee and all the workshop participants for the rewarding experience and productive discussion about different research approaches. acknowledgements go to taavi tiidor for taking the photos included in this paper. particular gratitude is extended to the owners of kirna manor house for hosting the practical part of the workshop. 12. short biography of the author(s) claudia valge ma student in cultural heritage and conservation and a lecturer on architectural paint research at the estonian academy of arts. she has supervised several extensive paint research projects on historical wooden houses, carried out paint investigation in various other historical buildings, and was the main organizer of the international colour measurement workshop conducted in estonia in 2019. sofia ceccarelli conservation scientist, phd student in the industrial engineering department at the university of rome tor vergata with a thesis on the characterisation of hygroscopic painted supports in cultural heritage with non-destructive infrared imaging techniques. she has worked on the high-resolution 3d digitalisation of artworks, colorimetric studies on cultural heritage and the development of a web-based platform for sharing metadata in regional projects. silvia bertacchi architect, phd in survey and representation of architecture and environment at the university of florence, research fellow at the department of architecture of the university of bologna. she is expert in 3d survey, photogrammetry, realitybased modelling and optimization for documenting and disseminating cultural heritage, including both shape and reliable colours. she is the author of several scientific papers on digitization of architectural heritage. andres uueni estonian academy of arts. andres has worked in different memory institutions, designing, developing information systems and led many cultural heritage digitisation and documentation projects, focusing on high-resolution imaging technologies. in 2014 andres was a co-founder of archaeovision llc and he has also started a phd program with the estonian academy of arts which focuses on cultural heritage 3d documentation and multi-spectral imaging. hilkka hiiop phd, professor of the estonian academy of art, department of conservation, tallinn, estonia. hilkka is a conservation expert and her phd thesis treated the conservation management of contemporary art. she has worked as a conservator of mural paintings in rome, supervised several conservation and technical investigation projects in estonia, curated exhibitions on topics of conservation and technical art history. anneli randla, phd, head of the department of cultural heritage and conservation, estonian academy of arts. studied art history and medieval studies in tartu, budapest and cambridge, worked at the national heritage board and has taken part in many conservation projects. her main research interests are: medieval ecclesiastical architecture, medieval murals, technical art history and the history of conservation. fabrizio ivan apollonio, phd, full professor, head of the department of architecture at the university of bologna. scientific coordinator of “larac – laboratory of surveying of architecture and city” and "lamovida laboratory of modeling and digital visualization for architecture", faculty of architecture. he contributed to several research programs about architectural drawing, representation and surveying. he published essays, reports, papers and books about urban surveying for the protection of architectural heritage and about architectural drawing. colour measurement and documentation in historical buildings: the case study of the kirna manor house in estonia 130 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140115 references carbonell rivera, j. p., montalvá españa, d. and lerma garcía, j. l. 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(eds) heritage wood: investigation and conservation of art on wood. cham: springer international publishing, pp. 109–122. doi: 10.1007/978-3-030-11054-3_6. 52 color culture and science journal vol. 13 (1) doi: 10.23738/ccsj.130206 does gender have an impact on the color preferences in fashion products? ítalo josé de medeiros dantas 1 , aline gabriel freire 2 , lívia juliana silva solino 2 , mariana nunes do nascimento 2 and heloisa mirelly ferreira alves 2 1 department of design, federal university of campina grande, campina grande, brazil. italodantasdesign@hotmail.com 2 department of textile and fashion, federal institute of education, science and technology of rio grande do norte, caicó, brazil. aline.freire@ifrn.edu.br, livia.solino@ifrn.edu.br, mariana.n.n@hotmail.com, heloisamirelly57@gmail.com corresponding author: ítalo josé de medeiros dantas (italodantasdesign@hotmail.com) abstract this paper is part of a project that aims to identify consumers' color preferences in fashion products. the results presented in this work are part of a survey developed in 2019. in fashion products, colors are responsible for adding value through emotional and aesthetic aspects, these preferences being essential points to build a marketable and attractive product. however, through history and cultures, it was noticed that certain colors, when applied to clothes, were positively seen in a society when worn only by men and others only by women. thus, this paper aims to identify how color preferences in fashion products change as the differences between genders are observed. the survey was conducted with 252 volunteers, 176 of whom were female, and 76 were male respondents; the results were analyzed using the ibm spss. as a result, a greater focus on the female gender in pinks and lilaceous hue was understood, while a lower preference for greenish hues. as for the male gender, the preferred hues were bluish, while the least preferred were pinks and lilaceous. it was concluded that genders play a certain role in color preferences in fashion products, identifying socially constructed characteristics through the history of colors as being responsible for those tendencies. it was possible to corroborate the social notion of the female gender preferring pinks hues and the masculine gender presenting tendencies of preferences to the bluish ones and a high refusal to the pinks and lilaceous – seen as women colors. keywords gender differences. color preferences. hue. color psychology. chromatic studies. fashion design. sex difference. received 10/02/2021; revised 03/04/2021; accepted 05/03/2021 does gender have an impact on the color preferences in fashion products? 53 color culture and science journal vol. 13 (1) doi: 10.23738/ccsj.130206 1. introduction colors are found in everything around us, from the artifacts to the clothes to the skin of the people (farina, 2006). therefore, an element of fundamental importance for the development of any product (baxter, 2011). the colors are presented as the first factor of perception in a visual stimulus (pina, 2009). in fashion, the color becomes even more indispensable, being used to develop garments, accessories and shoes (treptow, 2013). pina (2009) argues that color is an edifying element that can transmit sensations. therefore, the color is used as a basis for fashion collections development. in this way, the fashion collections are designed to attract the customer, and, in several cases, "the power of attraction does not depend only on color and light, but also on psychological effects" (farina, 2006:137). the human being ends up preferring a certain color over another because of empathy. in fashion collections, colors are used as a trend and as a way to demonstrate emotions, color semantics (pina, 2009). the relationship between the subject and color been positive or negative is directly linked to the environment in which they live and other factors such as age, education, and the individual's gender categorization (farina, 2006). gender becomes the focus of this paper when it is understood that it has evidence of strong levels of difference in color preferences (ellis and ficek, 2001). it is based on this that we emphasize the need to enter into these discussions bringing out as an object of study so pertinent for use and practical application of colors: fashion (jones, 2005; altıntaş and ağaç, 2008). regarding color preferences in fashion/clothing products, zhang (2013: 476) found black to be the most accepted color in the chinese environment, “the survey of style and color shows that black if fit for all styles and accepted by 90 % of the male and female”. in studies focused on children aged 6 to 8 years, it was determined that the colors preferred most by the girls for all garment types were magenta, red-violet, red, and red-orange, and the colors preferred by the boys for all garment types were black, blue, cyan, and yellow (kilinç, 2011). this work is based on the need to pay attention to the subjective preferences of products' aesthetic-symbolic content to future fashion users (löbach, 2001). this information allows us to create products that have a greater affective connection with consumers, avoiding product waste at the time of sale. also, it allows us to create a starting point to identify the core of tendency to color preferences in our society. color preferences in design products have been identified in other works as one of the main means of influencing consumers' purchasing decisions, realizing their relevance (yu et al., 2017; yu et al., 2018; luo et al., 2019). based on previously evidences that shows there are gender differences in color preferences (yu et al., 2020), it is understood that the social role that each gender has played for years in the chain of a society configures important delimitations in the ways they live, behave and consume products (silverman et al., 2007). furthermore, this study is necessary to verify whether there are signs of the reflex of socio-cultural categorization of gender in human cognition of molding subjective preferences in colors when in a scenario of selecting fashion products. 1.1. a brief background on color theory and color preferences relevant to color theories and to better understand the treaties proposed in this research, it is important to note that colors are composed of three essential attributes that configure their existence: hue, chroma, and lightness (holtzschue, 2011). thus, a) hue is configured as another word to describe what each color is, as well as being able to characterize a set of similar colors; b) chroma refers to the level of gray that exists in its composition; c) lightness refers to the level of the brightness of the color (zhang et al., 2019). these relationships shape people's daily lives and exchanges of values and information with artifacts, serving as a strong element of pre-judgment and instant connection (holtzschue, 2011). entering the field of color psychology, we discuss the effect of colors on individuals' cognition. sherin (2012:77) says that "a person's response to color and tone can help determine how information is understood and can affect whether a consumer buys a product or uses a client's services". this information is extremely important for the product development area since it deals with consumers' needs and desires (rathee and rajain, 2019). based on this, we bring up research on color preferences as a valid starting point for identifying patterns of aesthetic-symbolic preferences in consumers' cognition (singh, 2006; kilinç, 2011). these researches started in the studies of j. cohn when the researcher argued that color preferences came from a subjective value that was already born with individuals (taylor et al., 2013). at present, the theory with the greatest number of evidences is the ecological valence theory, which seeks to explain color preferences through the positive or negative relationship of human with the artifacts and objects that permeate our daily life, from elements of nature to industrial products (palmer and schloss, 2010). does gender have an impact on the color preferences in fashion products? 54 color culture and science journal vol. 13 (1) doi: 10.23738/ccsj.130206 1.2. gender differences in color preferences one of the first studies developed, in the 40s, determined that men and women tended to prefer colors in the same way, identifying traces of differences only to the orange colors, most preferred by men, and also on the yellow color, most preferred by women (eysenck, 1941). however, over time and with the expansion of studies in color preferences, several other studies have emerged to realize the existence of differences in color preferences, formalizing theories (he et al., 2011; zhang et al., 2019). later on, it was possible to identify those female children tended to prefer pink more, as women preferred reddish hues; male children and adult men preferred more lighttinted blue (burkitt et al., 2003; ling et al., 2006). one of the main theories that seek to explain the core of color preferences is called hunter-gatherer theory (regan et al., 2001; hurlbert and ling, 2007). thus, it discusses an existing relationship between the social roles that occupy the feminine gender and the masculine gender within a social organization, focusing on their survival adaptation, ending how this is reflected in color preferences (he et al., 2011). in this sense, this theory identifies the preference of women for warmer colors according to the tasks they tend to perform in a domestic context, such as identifying the quality of fruit based on its red or purple color) (he et al., 2011; zhang et al., 2019). meanwhile, the same scenario would tend to apply to the male gender, which, being considered in a context of nature, outside a domestic zone, tends to demonstrate preferences for colors such as blue and green (he et al., 2011; zhang et al., 2019). the authors mentioned above still presented a second theory, called social structural theory. in this, color preferences would be related to a search for equality of gender roles in society (he et al., 2011). based on this theory, zhang et al. (2019:969) explain that "men would prefer some stimulating colors such as yellow to increase their sociability, while women would prefer some energetic and disturbing colors such as orange to increase their aggression-hostility". in science, there is evidence that both confirms and refutes the theories. 2. objectives this research's main objective is to identify whether there are differences in color preferences in fashion products across binary genres. from this, three research hypotheses were defined to be tested: h1a. people's gender has a direct impact on how they prefer color in fashion. h1b. people's gender has a direct impact on how they prefer groups of hues in fashion. h1c. people's gender has a direct impact on how they prefer color lightness in fashion. 3. methodology in terms of its nature, the research is classified as applied, whose main characteristic is the application and use of knowledge in the fashion industry. classify as exploratory-descriptive research. as for its approach, it is classified as quantitative research (gil, 2008). concerning its methodological procedures, it is classified as a survey, "the purpose of a survey is to provide statistical estimates of the characteristics of a target population, some set of people" (fowler, 2014:8). thus, we sought to discover the preference profiles in colors for fashion products. "to do that we designate a subset of that population, a sample, from whom we try to collect information (fowler, 2014:8). 3.1. participants the research sought to understand the color preferences for fashion products among people considering the unique colors, the group of hues, and color lightness. in this way, it was also possible to perceive and discuss the color preferences between men and women. the survey's application was conducted with 252 people participated, 176 of them female and 76 men, aged between 7 and 64 years (table 1). table 1. profile of survey respondents 3.2. sample of colors based on the color chart developed by silva (2017; 2020) in her works, the survey's questionnaire had a total of 39 colors presented to the respondents. it was devised into 12 pure colors, 12 colors darkened with 50% black, 12 does gender have an impact on the color preferences in fashion products? 55 color culture and science journal vol. 13 (1) doi: 10.23738/ccsj.130206 colors lightened at 50% opacity, and three achromatic colors, arranged and divided into four groups of 5 hues and three lightness, and 1 group of 3 hues and three lightness (fig. 1). fig. 1. colors listed presented to the participants, together with the questionnaire (silva, 2017; 2020). 3.3. survey process the survey was conducted in late 2019 during a scientific and technological exhibition held annually by the federal institute of education, science, and technology of rio grande do norte, in brazil. it was decided to create a thematic room on colors at a science fair where the questionnaire was applied to attract a greater number of respondents to the questionnaire. the room was called “know your colors” and was designed to analyze the color temperature and contrast of people's skin and relate these variables to the use of colors in clothes and, in return, these people answered our questionnaire (fig. 2). the questionnaire's composition first sought demographic data, and in the second stage was selecting 5 of the colors that the respondents liked most when it comes to fashion products. two new ipads (6th generation) with a 10.2-inch retina screen and a resolution of 2160 x 1620 pixels at 264 dpi were used for the application. it was a guarantee that both have the same lighting settings, thus ensuring that respondents were subjected to the same visualization conditions of the colors and at the same time optimize the time of application of the questionnaires. fig. 2. the thematic room where the questionnaire was applied. the data obtained were analyzed using basic descriptive statistics and anova, focusing on identifying the levels of significance through the statistical analysis software ibm spss statistic 20. the results were compared among themselves, considering divergences and convergences as the central focus in perceptions between genders. this paper consists of an initial and exploratory discussion on color preferences since there are so few works focusing on fashion products, and this research in brazil is in the early stages. 4. results: what color do men and women prefer in fashion? this topic will be organized through the following three subtopics: unique colors, hue and color lightness. 4.1. color preferences within unique color at first, it is noticed that the color black (159 general choices) and white (75 available choices) has a common does gender have an impact on the color preferences in fashion products? 56 color culture and science journal vol. 13 (1) doi: 10.23738/ccsj.130206 consensus of preference between genders; both colors presented a higher level of preference in general and through genders (fig 3). then, concerning the perspectives of individual genders and going beyond the colors already mentioned, women tended to prefer a shade of dark red (47 choices) and magenta (42 choices), with this set being the four most prominent colors among the female gender. in contrast, four colors derived from green were also identified as the least preferred among the female gender. regarding male preferences, trends were identified for preferring the color gray (20 choices) and the color red (20 choices). unlike the female gender, the colors least preferred by men varied significantly, ranging from dark cyan (3 choices) to dark magenta (2 choices), violet (2 choices), and dark yellow (1 choice). for the hypothesis outlined in h1a, it was found that there is no significant difference in preferences for individual colors in fashion (p-value = 0.383 > 0.05) [1]. the hypothesis is rejected. fig. 3. main gender color preferences for fashion products [2]. 4.2. color preferences through the group of hues the second analysis of the results was divided between five hues: achromatic (black, white, and gray), greenish, bluish, yellow/orange and reddish, and pinks and lilaceous (see fig. 1). it was possible to observe that the most preferred hues for the research's general results are pink and violet, with 291 mentions, and greenish hues were the least preferred with only 170 mentions. however, those results are mainly influenced by the level of feminine representation in the research. regarding the differences in preferences between genders, it was found that there were 104 mentions of bluish hues among male people, and for pink and lilaceous hues, there were only 50 mentions, characterized as the last in the list. regarding the female gender, there were 241 mentions of pink and lilaceous hues, the largest number of choices, and 112 mentions of greenish hues, the least preferred group of colors (fig. 4). does gender have an impact on the color preferences in fashion products? 57 color culture and science journal vol. 13 (1) doi: 10.23738/ccsj.130206 thus, it is possible to understand that women have a greater preference for pink and lilaceous hues and men for bluish hues, which, in the study by heller (2013), presents the color blue as preferred among 46% of men, also being consonant with the found by ellis and fieck (2001), about colors in general. statically, it was found that there is no difference between the groups of hue in color preferences in fashion products for the male gender compared to the female gender (p-value = 0,145 > 0,05) [1]. so, regarding the hypothesis stated in h1b, the evidence indicates that it was not an accepted hypothesis. 4.3. color preferences through the color lightness in general, dark tones appear as the preferred type of color lightness, with 476 mentions, followed by light tones with 405 mentions and medium tones with 378 mentions (fig. 5). therefore, according to the general results, dark tones are the preferred lightness due to the greater preference for the color black in both genders. fig. 4. color preferences for fashion product through a range of colors [2]. fig. 5. color preferences for fashion product through the color lightness [2]. does gender have an impact on the color preferences in fashion products? 58 color culture and science journal vol. 13 (1) doi: 10.23738/ccsj.130206 there is a greater preference for medium tones among males with 139 mentions, followed by 131 mentions for dark tones and 110 for light tones; in general, black is the preferred shade among the men. thus, among the female gender, there is a predominance of preference for dark tones with 233 mentions, followed by 198 mentions of light tones and 154 mentions of medium tones; the black tone was preferred among women. what exactly differs from the research by fortamann-roe (2011), since the researcher identified a much greater male preference for dark tones and medium tones. regarding the hypothesis placed in h1c, it was not possible to identify any significant difference in color preferences across genders in fashion products for color lightness (p-value = 0.919 > 0.05) [1]. based on this, the hypothesis is indicated as rejected. 5. discussion: the reflex of gender social construction on color preferences in fashion products even though the results statistically suggest no difference in color preferences related to fashion products between genders, we can observe a much greater tendency for women to prefer pink and violet hues and men to higher reject it, preferring bluish hues instead (see fig. 4). these results were in line with other studies previously developed regarding color preferences in general, without sticking to any product type (fortamann-roe, 2011; heller, 2013; bonnardel et al., 2018). these data then suggest a more in-depth approach than would be the social dynamics of sexism rooted in a sociocultural context, this being brazil. this sexist thinking is very much in line with the global influences that the country has suffered and still suffers historically, mainly from the mass media. lobue and delocache (2011: 663) bring that "if pink is what helps define a girl, it is not surprising that boys would have the opposite reaction". thus, the thought of clothing is rooted in society as a daily communication vehicle attached to one's body, actively participating in a society's interpersonal relationships, becoming part of itself, and reflecting visual messages (jones, 2005). it is based on the thinking of fashion as a means of permeating a message that the male gender tends to create a departure from the use of clothing that brings the color pink as central since it automatically brings him closer to features that resemble the female gender (ben-zeev and dennehy, 2014; ishii et al., 2018). in brazilian society, among cisgender men of heterosexual orientation, this approach to femininity that the use of pink automatically brings, ends up being seen as something negative, as a denial of its masculinity (schwinn and funck, 2019). the idea of 'pink for girls and blue for boys' is a sociocultural concept established since the individual is a child (kilinç, 2011). the artifacts in the marketed for these age groups, such as toys, are limited and categorized through targeting the male gender, appropriating blue and green, and to the feminine, delimiting the colors pink and lilac. lobue and delocache (2011:665) go on to explain that "while girls are developing a preference for pink with age, boys are developing an avoidance of pink at the same time". these reinforced influences since childhood grow with our social preconceptions and become part of the judgments that we develop daily, guiding our purchase intensities sometimes only in the colors that certain artifacts carry and how they impact our social image, where men tend to refuse to wear a certain set of clothes because they are pink, lilac or red (heller, 2013; benzeev and dennehy, 2014; ishii et al., 2018). 6. final considerations the research demonstrated the need further to investigate color preferences with a focus on fashion products. the results suggest that the preferences identified in this work are not derived either specifically from what is proposed in hunter-gatherer theory or social structural theory. as discussed earlier, the core of this color preference has been the pink and blue semantics' socio-cultural construction when related to genres. the results reveal this categorization of sexism projected in color as being more present in male fashion choices. this work starts developing research in brazil in an area not explored before. creating a basis for what to be formalized and validated in future research as a theory about the potentializing and appearance of color preferences in fashion products and their socio-cultural and semantics perception. besides, designers can find an opening of possibilities to explore the dimension and the psychological relationship between color-productconsumer. some previous studies suggest that the female preference for the color pink is directly linked to the age of the people studied, occurring mainly in children or young people. however, relationships between age and color preferences were not analyzed in this research and can be explored in other future studies. does gender have an impact on the color preferences in fashion products? 59 color culture and science journal vol. 13 (1) doi: 10.23738/ccsj.130206 7. conflict of interest declaration the authors declare that there is no conflict of interest regarding the publication of this paper. 8. funding source declaration this research did not receive any specific grant from funding agencies in the public, commercial, or not-forprofit sectors. however, during the execution of the thematic room where the survey was applied, the federal institute of education, science and technology of rio grande do norte (caicó, brazil) provided material and structural support to perform the survey. 9. acknowledgment we wish to thank all those who took the time to visit our thematic room on colors at the 6th scientific, technological and cultural exhibition of the ifrn campus caicó (2019) and to contribute answering our survey. we would also like to thank our colleagues at the ifrn/ca who promptly helped us to assemble and organize our thematic room. these people were vanda silva, breno moore, ionara tereza, esron candeia, amanda souza, ananda medeiros, lavínia araújo, raiane dantas, marilia rodrigues, luiz eduardo and maria eugênia. thank you for all the support provided. 10. short biography of the authors ítalo josé de medeiros dantas master's student in design at the ufcg/uad (brazil) and fashion designer at the ifrn (brazil). research member of the pro-cor do brasil association and the language of color and environment color design study groups from the aic. conducts research in the field of visual and semantic color messages, color psychology applied to fashion, and color preferences in clothing products. aline gabriel freire – textile engineer at the ufrn (brazil), master in textile engineering at the ufrn (brazil) and fashion stylist at the senai (brazil). professor in the areas of textiles, clothing and fashion at the ifrn (brazil). researcher and extensionist in the areas of colors applied to the creative process, innovation in textile materials, modeling and circular economy. lívia juliana silva solino – professor and coordinator of the fashion design undergraduate course at ifrn (brazil). undergraduate in fashion design at ufc (brazil) and master in production engineering at ufrn (brazil). she works in the areas of slow fashion, innovation in fashion products, processes and color psychology. in addition to actively participating in university extension, promoting the circular economy. mariana nunes do nascimento technician in clothing production and undergraduate in fashion design by the federal institute of rio grande do norte (brazil). she worked as a research student at the textile and clothing research center (ifrn). conducts research in the area of product development to elderly, shoe ergonomics, color psychology applied to fashion and color preferences in clothing products. heloisa mirelly ferreira alves undergraduate in fashion design by the federal institute of rio grande do norte (brazil). she worked as a research student at the textile and clothing research center (ifrn). conducts research in the area of product development to elderly, shoe ergonomics, color psychology applied to fashion and color preferences in clothing products. notes [1] when the p-value is higher than 0,05, we reject the hypothesis stated. 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(2019). hue, chroma, and lightness preference in chinese adults: age and gender differences. color research and application, 44, pp. 967-980. color culture and science cultura e scienza del colore ccsj volume 12 number 2 2020 issn 2384-9568 color culture and science journal cultura e scienza del colore ccsj jcolore.gruppodelcolore.it issn 2384-9568 doi: 10.23738/ccsj.00 ance e227716 road: the directory of open access scholarly resources registrazione presso il tribunale di milano n. 233: 24/06/2014 volume 12, number 2, july 2020 doi 10.23738/ccsj.120200 publisher gruppo del colore – associazione italiana colore www.gruppodelcolore.org registered office: piazza carlo caneva, 4 20154 milan (it) peer review process all articles submitted to the "color culture and science journal” are peer-reviewed according to the following procedure: first review level the associate editors evaluate each article in order to determine if the topic and content are of interest to the journal. once the article passes the initial review, the associate editors select several referees from the editorial board based on their expertise in a particular subject area or topic. second review level each article is reviewed by two or three referees and submitted to a double-blind peer review process where both the authors and the reviewers are kept anonymous. referees are asked to evaluate the manuscript based on the following criteria: − originality − relevance to journal’s aims and scope − technical merit and/or validity − soundness of methodology − completeness of the reported work − conclusions supported by the data − correct acknowledgment of the work of others through reference − effectiveness of the manuscript (organization and writing) − clarity of tables, graphs, and illustrations − importance to color researchers − relevance to color practices if the article is accepted with major revisions by the referees, the author(s) are asked to improve the article according to the suggestions of the referees. the revised article will then be submitted to a further review. after collecting the referees' reports, the associate editors make a recommendation on the acceptability of the article to the editor-in-chief. editor-in-chief maurizio rossi (politecnico di milano, it) deputy editor alessandro rizzi (università degli studi di milano, it) associate editors josé luis caivano (universidad de buenos aires, ar) vien cheung (university of leeds, uk) marco gaiani (alma mater studiorum università di bologna, it) robert hirschler (serviço nacional de aprendizagem industrial, br) agata kwiatkowska-lubańska (academy of fine arts, kraków, pl) marcello picollo (ifac-cnr, it) verena m. schindler (chair aic s.g. environmental colour design, ch) renzo shamey (nc state university, usa) francesca valan (studio valan, it) editorial board members the complete and updated list of the editorial board members involved in the peer review process is available on the ccsj website: http://jcolore.gruppodelcolore.it/ojs/index.php/ccsj/about/editorialteam topics the ccsj accept papers on a wide range of topics on color, including and not limited to the following: 1. color and measurement/instrumentation. colorimetry, photometry and color atlas: method, theory and instrumentation; quality control and food coloring, dyes, organic and sustainable color. 2. color and digital. reproduction, management, digital color correction, image processing, graphics, photography, film and video production, printmaking and 3d print, artificial vision, virtual reality, multispectral imaging, data visualization. light field imaging. multi-sensor fusion. color localization, recognition, hdr imaging, adas systems. 3. color and lighting. metamerism, color rendering, adaptation, color constancy, appearance, illusions, color memory and perception, color in extra-atmospheric environments, lighting design, lighting technologies, visual comfort. 4. color and physiology. mechanisms of vision in their experimental and theoretical aspects, color vision and color appearance, deficiencies, abnormalities, clinical and biological aspects, synesthesia, health, well-being. 5. color and psychology. phenomenology of colors, color harmonies, color & form, perceptive, emotional, aesthetic and diagnostic aspects. 6. color and production. food and beverages, agriculture, textiles, plastic materials, ceramics, paints, gemology, color in the food industry. 7. color and restoration. archaeometry, painting materials, diagnostics and techniques of conservation, restoration and enhancement of cultural heritage. 8. color and environment. representation and drawing, urban planning, project of color, architecture, interior design, landscapes & horticulture, color and architectural syntax, territorial identities, biodiversity. 9. color and design. furniture, cmf design, fashion, textiles, textures, cosmetics, food design, museography. 10. color and culture. arts and crafts, history, philosophy, aesthetics, ethno-anthropology, graffiti, geology, sociology, lexicology, semantics, anthropology of vision, food culture and heritage, color naming. 11. color and education. pedagogy, didactics of color, aesthetic education, artistic education. 12. color and communication/marketing. graphics, communication, packaging, lettering, exposure, advertising. http://jcolore.gruppodelcolore.it/ojs/index.php/ccsj/about/editorialteam 3 color culture and science journal vol. 12 (2) issn 2384-9568 table of contents editorial 5 maurizio rossi color segmentation and neural networks for automatic graphic relief of the state of conservation of artworks 7 annamaria amura, anna tonazzini, emanuele salerno, stefano pagnotta, vincenzo palleschi doi: 10.23738/ccsj.120201 περὶ χρωμάτων (peri chrōmatōn): colour formation and investigation method. 16 maria fernanda ferrini doi: 10.23738/ccsj.120202 graphical interpolation of munsell data 21 pietro paglierani, simone liberini, alessandro rizzi, francesca valan doi: 10.23738/ccsj.120203 francesco algarotti explains newton’s prism experiment to ladies 31 paola magnaghi-delfino, giampiero mele, tullia norando doi: 10.23738/ccsj.120204 light and colour at the theatre in paolo bini's works for francesco de gregori 37 maria letizia paiato doi: 10.23738/ccsj.120205 floral decorations and colours in naples. the case of villa pappone in posillipo 44 maria martone, alessandra marina giugliano doi: 10.23738/ccsj.120206 food waste: potential bioresource for the colour of polymers 53 annalisa di roma, alessandra scarcelli doi: 10.23738/ccsj.120207 4 color culture and science journal vol. 12 (2) issn 2384-9568 the restoration of the basilica minore di maria ss. incaldana in mondragone (northern campania): the role of color. 62 francesco miraglia doi: 10.23738/ccsj.120208 archaeological digital anastylosis. from survey to lighting analysis 67 lia maria papa, laura bellia, pierpaolo d’agostino, gennaro spada, giuseppe antuono doi: 10.23738/ccsj.120209 transmitted light imaging in vis and ir, in the study of paintings: a brief report on the behavior of the main historical pigments 79 miquel herrero-cortell, paola artoni, marta raïch doi: 10.23738/ccsj.110210 coloumn review: l'anima e la magia dei colori. uso consapevole dei colori nella vita 89 renata pompas 5 color culture and science journal vol. 12 (2) issn 2384-9568 editorial dear readers, with vol 12 n. 2 we close the seventh year of ccsj. since 2019 the ccsj website is available via the open journal system. this allows a better indexing of the published articles and will guarantee the compatibility with open archives initiative protocol for metadata harvesting (oai-pmh). in 2020, despite the severe covid19 crisis, we continued with the publishing activities and we refined our archiving policy to guarantee long-term access of our issues, making agreements with the biblioteca nazionale centrale di firenze. since 2014 we have published 12 volumes for a total of 14 issues. since 2015 we have applied the double blind peer review and since 2016 we have applied the doi system. it is also useful to recall the importance of the concept of “diamond open access” under which our journal is published: the journal is completely free for both readers and authors. this is possible thanks to the voluntary support of the members of the "associazione italiana colore" who work in the editorial committee, thanks to the associate editors, thanks to the deputy editor alessandro rizzi and the president of associazione italiana colore marcello picollo. a special thanks goes to chiara storti of the biblioteca nazionale centrale di firenze (bncf) the main official library of italy, to filippo cherubini of ifac-cnr who manages the open journal system, to veronica marchiafava, the secretary of our association, for the management of doi database and to andrea sinicalco, the vice-president of our association, for the graphic support. many of these people are also involved in the organizing committee of the important meeting in 2021: the aic 14th congress that will be held for the first time in italy organized by the associazione italiana colore (www.aic2021.org). the peculiarity of our journal, also written in the statute of our publisher, the associazione italiana colore, is to collect papers on color and related areas in a multidisciplinary way. this basically means that in our peer review process we could have papers ranging from the science of colorimetry to the culture of color in the history of art. moreover, these papers have very different styles and ways of writing, as diverse is the group of the peer reviewers that constitutes our editorial board. the ccsj accept papers on a wide range of topics on color, including and not limited to the following: 1. color and measurement/instrumentation. colorimetry, photometry and color atlas: method, theory and instrumentation; quality control and food coloring, dyes, organic and sustainable color. 2. color and digital. reproduction, management, digital color correction, image processing, graphics, photography, film and video production, printmaking and 3d print, artificial vision, virtual reality, multispectral imaging, data visualization. light field imaging. multi-sensor fusion. color localization, recognition, hdr imaging, adas systems. 3. color and lighting. metamerism, color rendering, adaptation, color constancy, appearance, illusions, color memory and perception, color in extra-atmospheric environments, lighting design, lighting technologies, visual comfort. 4. color and physiology. mechanisms of vision in their experimental and theoretical aspects, color vision and color appearance, deficiencies, abnormalities, clinical and biological aspects, synesthesia, health, well-being. 6 color culture and science journal vol. 12 (2) issn 2384-9568 5. color and psychology. phenomenology of colors, color harmonies, color & form, perceptive, emotional, aesthetic and diagnostic aspects. 6. color and production. food and beverages, agriculture, textiles, plastic materials, ceramics, paints, gemology, color in the food industry. 7. color and restoration. archaeometry, painting materials, diagnostics and techniques of conservation, restoration and enhancement of cultural heritage. 8. color and environment. representation and drawing, urban planning, project of color, architecture, interior design, landscapes & horticulture, color and architectural syntax, territorial identities, biodiversity. 9. color and design. furniture, cmf design, fashion, textiles, textures, cosmetics, food design, museography. 10. color and culture. arts and crafts, history, philosophy, aesthetics, ethno-anthropology, graffiti, geology, sociology, lexicology, semantics, anthropology of vision, food culture and heritage, color naming. 11. color and education. pedagogy, didactics of color, aesthetic education, artistic education. 12. color and communication/marketing. graphics, communication, packaging, lettering, exposure, advertising. in an era in which sectoral super-specialisation has reached extreme limits, having a multidisciplinary journal, on a multidisciplinary theme such as color, favors the development of problem solving skills that are based on the psychological methodologies of lateral thinking. july, 2020 the editor-in-chief maurizio rossi full professor of lighting design and design methods politecnico di milano 73 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140109 fine arts on film: the hand-painted work of stan brakhage sabrina negri department of cinema studies and moving image arts, university of colorado boulder, sabrina.negri@colorado.edu abstract this paper will approach the topic of color in cinema by examining the case of the hand-painted films made by experimental filmmaker stan brakhage. specifically, i will present the example of some hand-colored pre-print elements belonging to the national cinema museum in turin and preserved at the haghefilm lab in amsterdam in 2011. i will argue that these films challenge traditional understandings of cinema by belonging simultaneously to the realm of film and to that of the fine arts and will show the consequences of this liminal position both at a practical and a theoretical level. in particular, i will explore the challenges related to the preservation of some of these films, and will relate them to broader issues of originality, medium specificity, and philological recreation of experimental cinema practices. keywords cinema studies, film preservation, experimental cinema, stan brakhage, hand-painted film, originality received 04/11/2021; revised 16/12/2021; accepted 03/01/2022 fine arts on film: the hand-painted work of stan brakhage 74 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140109 1. what is cinema? old questions, new answers starting in the early 2000s, the introduction of digital technology in the realm of cinema has rekindled scholarly interest in the ontology of the medium. questions like “what is cinema?”, which seemed to have lost their appeal for the academic world, have attracted renewed attention on the part of film theorists as soon as digital technologies started supplanting analogue ones. while some scholars have decried the end of cinema in the digital age, others have seen in the digital revolution only one of the many technological transitions that cinema has been going through since its birth. following the need for a compass to help navigate such turbulent times, works of classical film theory such as andré bazin’s famous collection of essays on the ontology of cinema have been recovered from their decades-long neglect to be reread and reinterpreted in the light of the changed technological landscape; concurrently, different disciplines have been integrated with film theory in order to provide new answers to deep-rooted questions. as i have argued elsewhere, including the practice of film restoration and preservation in discussions over the ontology of cinema can contribute to a fuller understanding of some of the issues raised by the recent technological transition (negri, 2016). for instance, film preservation engages issues of originality, medium specificity, and mechanical reproducibility by virtue of its being the only type of restoration in which the endproduct is a copy. if it might seem arbitrary to operate a distinction between an original and a copy when dealing with an art that is based on technical reproduction, it is also true that, from a film restoration perspective, any copy of a film is an original in and of itself, insofar as any copy displays technological and historical peculiarities that render it unique. digital technology hardly changes this; if anything, film preservation highlights some continuity from the analogue era by showing that certain technological elements cannot be reproduced regardless of whether the restoration is performed digitally or analogically (fossati, 2018). a particularly relevant example of this mechanism is provided by experimental cinema. by breaking the rules of mainstream narrative filmmaking in its modes of production, distribution, and exhibition, experimental cinema emphasizes the complexity of cinema’s nature and the need for a broader and more flexible understanding of the medium. because of the lack of standardization of experimental cinema practices, the preservation of experimental films can be incredibly challenging while also highlighting complexities and contradictions that are integral to cinema itself. in this essay, i will examine the case of stan brakhage’s hand-painted films by focusing on some film elements related to his spring cycle (1995), owned by the museo nazionale del cinema in turin, italy, and preserved at the haghefilm film lab in amsterdam in 2011. i will argue that brakhage’s filmmaking practice blurs the line between cinema and the fine arts, and that this hybrid nature can be best appreciated by looking at the preservation of his films. acknowledging brakhage’s hand-painted work’s liminal position affects our understanding of cinema by broadening the range of forms that the medium can assume at different stages of its existence, including the archival one. 2. stan brakhage’s experimental filmmaking when stan brakhage began experimenting with fully hand-painted films in the 1980s, he was already considered one of the founding fathers of american experimental cinema. according to experimental cinema scholar p. adams sitney, it is generally impossible to attribute the stations of evolution of avant-garde cinema to the invention of a single filmmaker, with one notable exception: the forging of the lyrical film by stan brakhage (sitney, 2002, p. 155). as sitney writes, the lyrical film postulates the film-maker behind the camera as the first-person protagonist of the film. the images of the film are what he sees, filmed in such a way that we never forget his presence and we know how he is reacting to his vision. […] in the lyrical film, as brakhage fashioned it, the space of the trance film, that longreceding diagonal which the film-makers inherited from the lumières, transforms itself into the flattened space of abstract expressionist painting. […] the film-maker working in the lyrical mode affirms the actual flatness and whiteness of the screen, rejecting for the most part its traditional use as a window into illusion. (sitney, 2002, p. 160) in other words, the lyrical film as conceived by brakhage is an expression of the subjectivity of the filmmaker, who strives to reproduce on the screen his own visual perception. this idea is ripe of consequences: while initially still working in the legacy of maya deren, who also tried to translate subjective experience into film, brakhage has nonetheless been pushing for a more radical reinvention of film form since his early works. a consequence of this styilistic and ontological transformation is the refusal of renaissance perspective, embodied by the diagonal composition which had been a staple of traditional filmmaking since the lumière brothers, in favour of a flat space that is more influenced by abstract expressionist painting, particularly that of fine arts on film: the hand-painted work of stan brakhage 75 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140109 jackson pollock, than by narrative cinema. the screen is therefore no longer a window into an illusory world, but rather a canvas for the filmmaker’s vision. brakhage’s idea is further clarified in his own writing. in the often-cited opening of his book metaphors on vision from 1963, brakhage explains the drive behind his filmmaking work: imagine an eye unruled by man-made laws of perspective, an eye unprejudiced by compositional logic, an eye which does not respond to the name of everything but which must know each object encountered in life through an adventure in perception. how many colors are there in a field of grass to the crawling baby unaware of ‘green’? (brakhage, 1963, p. 30) here, brakhage calls for the recuperation of the perceptual innocence of a child who has not yet entered the realm of language and is therefore able to distinguish all the colors that adults group under the linguistic label of “green”. the search for this pre-linguistic innocence includes a rejection of the laws of perspective, which brakhage sees as artificial and arbitrary. his commitment to lyrical cinema, in different ways throughout his life, is brakhage’s way to go back to that irretrievable unprejudiced vision. in the earlier part of his career, brakhage experimented mostly with montage, superimpositions, the splicing together of positive and negative film and the manipulation of the film stock both at the development stage and in post-production. in reflections on black (1955), for instance, the influence of maya deren’s “trance film” is still clear, but the search for a new form that could explore more directly the dynamics of vision and consciousness starts emerging. reflections on black portrays the inner vision (or hallucination?) of a blind man. while most of the shots are quasi-naturalistic, the use of repetitions, jump-cuts, and flashes of light betray the subjective nature of the man’s perception. in reflections on black, brakhage also starts working directly on the film stock to achieve effects that the camera alone could not produce. the man’s blindness is symbolized by star-shaped figures scratched directly on film so as to erase his eyes, or substitute them with a different type of metaphorical vision. the direct intervention of the artist on film materials is key to brakhage’s poetics, as a way to both work around the limitations of the camera and leave a distinctly authorial mark on his work. from this perspective, the climax of brakhage’s research could not be other than cameraless films. after all, the lens of a camera is in itself an eye ruled by compositional logic, and color film stocks are manufactured to appeal to a taste that is already poisoned by socially-created expectations – in brakhage’s words, “that picture post card effect (salon painting) exemplified by those oh so blue skies and peachy skins” (brakhage, 1963, p. 25). fig. 1. reflections on black (stan brakhage, 1955). the man’s blindness is symbolized by star-shaped scratches on the film’s emulsion. the earliest and probably best-known example of this new inspiration is the cameraless film mothlight (1963), a collage of organic material (leaves, seeds, flowers, insect wings) glued in-between two perforated 16mm mylar tape strips – so that mothlight is not only a cameraless film, but technically also a filmless film. even though brakhage replicated the experiment on 35mm with the garden of earthly delights in 1981, this production process was too labour-intensive to become a staple of his filmmaking. his hand-painted films, though radically different from these collage works, can be seen as embodying the same desire to portray a vision freed from the constrains of the camera, of color film emulsions, of culture in general. brakhage had already began painting on film earlier in his career, but it was not until the late 1980s that he began making entirely hand-painted films on a regular basis. this shift in style is certainly due to practical reasons (making hand-painted films is cheaper as it leaves out the negative processing stage, it can be done without camera equipment, etc.), but the deep reason probably lies within brakhage’s later interest in what he calls “hypnagogic vision” – that is, what the eye sees when the eyelids are closed. hypnagogic vision is the climax of brakhage’s research on the subjectivity of perception. what is more subjective than one’s vision when their eyes are closed? fine arts on film: the hand-painted work of stan brakhage 76 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140109 it is important to remark that this kind of vision is different from imagination or fantasy; rather, it is a fully perceptual experience, free from any referent in the world outside of the seeing subject. it is pure color, the closest an adult can get to the “unprejudiced eye” of the child who has not yet learned that the grass is green. no cameras or color film stocks can possibly reproduce those images; only the hand of the artist himself can. in an interview, brakhage himself links hypnagogic vision with painting, specifically abstract expressionist art. he said: somewhere after beginning to give attention to what i see when my eyes are closed, i recognised pattern likeness to jackson pollock’s interwoven whirls of paint, and then i realised that i had seen it before […]. it began very quickly to touch some childhood memories. (smith, 2017, p. 42) from this excerpt, the connection between hypnagogic vision, abstract painting, and childhood perceptual innocence is clear. only the direct intervention of the artist on the film strip can replicate what the artist sees in the most unmediated manner. painting alone, however, is not enough as it lacks one key feature of perceptual experience: movement. for this reason, the film strip is more than a canvas, but is rather an object that fulfils its purpose only when projected. fig. 2. spring cycle (stan brakhage, 1995). pre-print materials. courtesy of daniela currò. 3. spring cycle (1995) and the issue of originality from a production perspective, the 16mm film strips hand-painted by brakhage can be considered pre-print materials – that is, film elements that are not supposed to be projected but are needed to produce the projection print. unlike what usually happens with traditional narrative cinema, though, the processing of these films is rather complex and can be considered as part of the making of the film itself. an example of this complexity is provided by the instructions that brakhage wrote to sam bush, lab technician and frequent collaborator of brakhage, with regards to the printing process to be used for the 1998 hand-painted film the birds of paradise: i want it ... printed thus: superimpose loops #1 and 2, then superimpose loops #2 and 3, then superimpose loops #1 and 3 ... (take each loop around long enough so that the mobius effect of #1 and #2 has occurred at least once – i.e. each flipped once in the printing: you can also go into the frames of #1 and/or #2 [diagram here] as you, say, run the moebius loops through a 2nd or 3rd time. then i'd like a brief (1 minute and a half minute) interlude where loops #1 and #2 superimposition and loops #2 and #3 supers are bi-packed, all; then, finally breaking open into a non-orange negative section of the above bi-pack on non-orange negative and finally loops #1and #3 superimposition on non-orange negative... p.s. don’t frame-in on the single perf #1 and #3 combination and/or on #3 at all in the print – i.e. let it be a kind of exact refrain in all this. from this description, included in a private correspondence between marylin brakhage and luca giuliani (former head of the archive of the national film museum in turin), it is clear that the hand-painted materials represent just one of the stages of the production of the finished film, and that brakhage exerted complete control over every single step of the workflow. given the enormous difference between the hand-printed strips and the finished product, which element constitutes the “original” film by brakhage? the answer is not easy. mark toscano has worked on several preservation projects of experimental films at the academy film archive, including films by brakhage. in his essay “archiving brakhage”, toscano goes over the artist’s fine arts on film: the hand-painted work of stan brakhage 77 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140109 working habits in order to map possible preservation strategies for such complex productions. for instance, he describes brakhage’s habit of editing directly on the positive print, leaving the camera negative alone – if there even was a camera negative, given brakhage’s preference for reversal film. in this case, toscano writes, the edited positive is the artist’s original. (toscano, 2006: 15) in this case, originality is placed in the author’s idea of the finished work. the camera negative, which would normally be considered the best source element for a restoration, is only a necessary step to fulfil the author’s creation, but it is not an original in itself. this is an example of how experimental cinema can diverge from traditional narrative filmmaking both in its practices and in its restoration processes, due to the frequent presence of an individual author and to the creative freedom governing every step of a film’s making. as we will see shortly, the case of hand-painted films complicates this already complex scenario. from this account, it is clear that originality in cinema is a manifold concept that shifts depending on the perspective adopted, and in turn influences the broader issue of the nature of cinema as a medium. this complexity emerges more clearly in film restoration, where it is necessary to define what is meant by “original” before undertaking the restoration project. for instance, a film might have been released in different versions, each of them “original” in its own right. the case of experimental films is even more complex since, as we have seen, there are many stages to the production of a film, each of them unorthodox compared to those of traditional narrative filmmaking and therefore revelatory of the artist’s creativity and artistic vision. in the case of hand-painted films the problem is even more complicated, as shown by the film elements related to spring cycle, a 16mm hand-painted film that brakhage made in 1995 and sold to the national film museum in turin in 1997. when the museum decided to undertake a preservation project on spring cycle in 2011, it was necessary to understand exactly what the original printing process was and, concurrently, what was the nature of the elements in their possession. the materials conserved at the museum consisted of four film cans with one short hand-painted fragment in each can. the title on one of the cans was spring cycle, while the other three had “mobius” written on them. an email correspondence with marylin brakhage clarified that “mobius” was not a title, but rather a reference to the artist’s technique. brakhage used to tape film strips in the shape of a mobius loop, which is a loop with a half-twist in it, to be printed successively on the same film stock in a series of superimpositions. this is confirmed by the writing on the label on one of the film cans, reading “’spring cycle’ loops a+b/ mobius b,c+ d”. as mrs. brakhage recalls, “after receiving a print back from the lab, made from his painted film, from directions such as these, stan would then make final edits and that, then, would serve as the original work from which an internegative would be made for further printing.” the printing and editing stage are therefore integral part of the production process, and are controlled by the artist as much as the hand-painting on blank film. brakhage himself was very clear on this. in his description of spring cycle, he wrote: “note: i am the sole author of this film: sam bush of western cine service, denver, is a paid employee; and i've added the credit, at end, simply to fairly praise his workmanship”. this shows how brakhage considered the lab work to be part of the making of the film, a film of which he was the only author. if, as mrs. brakhage writes, originality in this case should be attributed to the internegative made after printing the hand-painted strips according to brakhage’s instructions, what is to be made of the hand-painted strips themselves? are they only pre-print elements like any other? the answer to these questions depends on the perspective we decide to adopt. if the focus is on the finished work, the film that is going to be projected as the author meant, then the hand-painted fragments are only one stage on the path towards the screen. however, this answer is clearly unsatisfactory; how can a work handpainted by the artist himself not be considered an original? a different answer is possible, although it requires a shift in perspective from a conception of film as a series of images projected on a screen to one of film as an archival object. this new perspective would bring cinema closer to the fine arts, where a work is considered unique and irreproducible by virtue of its being the direct product of an authorial effort. in fact, brakhage’s handpainted films cannot be mechanically reproduced in any way, as all their nature is indissolubly tied to their physical characteristics, including the materiality of their colors. the national cinema museum preserved the moebius loops that brakhage made in the production process of spring cycle at the haghefilm lab in amsterdam in 2011. despite their status as pre-print materials, these film strips have been preserved as they were found – that is, without being superimposed one to the other as brakhage indicated in his note to sam bush. each of them was both scanned in hd resolution and photochemically duplicated on 16mm film stock using a matibo debrie contact printer with no wet gate, in order not to damage the original paint. the decision to preserve the loops in their original form testifies to the original status of these objects, which can be considered fine arts on film: the hand-painted work of stan brakhage 78 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140109 works of art in and of themselves regardless of their use as pre-print materials in brakhage’s making of spring cycle. nonetheless, the outcome of this preservation, as it happens with any preservation work, is nothing but a reproduction. in the case of experimental cinema, because of the artist’s direct intervention on the film strip, this paradox is more apparent; still, it is a paradox that informs any preservation work and shows cinema’s own paradoxical nature as a medium based on mechanical reproducibility, and yet made of objects that are unique and, in many ways, irreproducible. the example of brakhage’s spring cycle shows how any restoration of these materials, be it analogue or digital, is bound to produce a ghost of the original, with which it would share no more than its disembodied appearance. rather than lamenting the loss of the object in reproduction, though, this scenario highlights the multifaceted nature of cinema, that cannot be reduced to one aspect or the other, but is rather the product of the interaction of different drives, materials, experiences, archival artifacts. at the same time, it shows some aspects of continuity between the analogue and the digital realm, insofar as, in both cases, the outcome of a preservation work shares only some features with its source material. if brakhage’s hand-painted work can be considered as fine arts on film, it is because some aspects of cinema can be likened to painting, including the uniqueness of some of the objects that can be found in archives. this perspective could open up new exhibition strategies, closer to those of the fine arts, which would highlight the value of the objects while teaching a new history of cinema where the film would no longer be only a story, but also a work of art not dissimilar from a painting. 4. conflict of interest declaration the author declares that there is no conflict of interest related to the publication of this essay. 5. funding source declaration this paper was written as part of the author’s research appointment as an assistant professor at the university of colorado, boulder. no additional sponsors or grants funded the writing of this essay or the research involved. 6. acknowledgment my deepest thanks go to luca giuliani, former head of the film archive at the national cinema museum in turin, italy, who has shared with me precious information and documents related to the preservation of spring cycle with immense generosity. stefania carta, stella dagna, and anna sperone, film archivists and preservationists at the same institution, worked on the preservation of spring cycle at the haghefilm laboratory under the supervision of daniela currò, as part of the haghefilm foundation internship program in 2011. to all of them go my gratitude and admiration. 7. short biography of the author sabrina negri sabrina negri (ph.d. 2017, cinema and media studies, university of chicago) is an assistant professor in the department of cinema studies and moving image arts at the university of colorado boulder. her current research interests include the digitization of analogue film materials and the epistemological value of archival film. references fossati, g. (2018) from grain to pixel: the archival life of film in transition. amsterdam: amsterdam university press. negri, s. (2016) “simulating the past. digital preservation of moving images and the 'end of cinema'”, cinéma&cie xvi, 26/27, pp. 45-54. sitney, p. a. (2002) visionary film: the american avant-garde, 19432000. new york: oxfrod university press. smith, v. (2018) the hand-painted films of stan brakhage: an interdisciplinary and phenomenological exploration of painted moving images. ph.d. thesis, university of portsmouth. toscano, m. (2006) “archiving brakhage”, journal of film preservation 72, pp. 13-25. 24 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140103 the long-term development of three-color kodachrome. an odyssey from the additive to the subtractive method of color reproduction nicolas le guern evry/paris saclay university, cokin kt s.a.s.u., france, nicolas.leguern@gmail.com abstract the introduction of three-color kodachrome in 1935 was possible thanks to the long collaboration between the independent inventors leopold mannes and leopold godowsky and the managers of the kodak research laboratory at rochester, new york. this paper considers this long research work initiated in 1917 by examining the technological solutions mannes and godowsky progressively followed, in the historical context of the first cinematographic additive processes. besides the technological context, the paper analyzes the evolution of mannes and godowsky position into kodak research. working independently at the beginning, the two young men were funded by their families first, then by the eastman kodak company and kuhn, loeb & co, experimenting in their personal laboratory. in a second step, mannes and godowsky were finally employed by kodak in 1931 as consultant researchers and incorporated with the team of the kodak research laboratory at rochester. in the mid-1930s mannes and godowsky were able to develop a two-color cinematographic process, which finally evolved in the three-color kodachrome process. this innovative process was announced in april 1935, despite the fact that the kodak researchers did not succeed in finding a correct developing process for exposed films. an immense amount of work was done in the american laboratory to find a correct sequence of chromogenic development in the summer 1935. this long research odyssey ended when the kodak research team managed to drastically simplify the developing process of exposed kodachrome rolls in 1938, encouraged by the recent german competition and the agfa color neu process. keywords: color photography, kodachrome, eastman kodak, additive technology, subtractive technology, industrial research, kodak research laboratory. received 29/07/2021; revised 20/12/2021; accepted 27/01/2022 the long-term development of three-color kodachrome. an odyssey from the additive to the subtractive method of color reproduction 25 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140103 1. introduction with the long-term research undertaken by leopold mannes and leopold godowsky for a three-color multi-layer process, a new form of innovation took place at the eastman kodak company (mentioned below as kodak). it was the alliance between independent research and the industrial research organization of one of the main film manufacturers of the period. given the final result of the three-color kodachrome released in 1935, this scientific collaboration can be judged as a positive, successful one. the kodachrome was a three-color reversal film which produced a positive image on a transparent base, and which was originally available as a motion picture film and then as a still film. it was the first commercialized color film to use the subtractive method of color reproduction, that involved the selective analysis and absorption by at least three superimposed layers of the red, green and blue components of a filmed subject. before kodachrome, the additive method of color reproduction was favored by inventors. using the theory of the trichromatic color vision of the human eye, this method implied the filming of separation views through at least two colored filters, and the reproduction of the natural colors of the subject in adding the separation films obtained by projecting them through the same filters. the full collaboration necessary for the development of the kodachrome differed from the model of the lenticular kodacolor’s development, for which patent rights were purchased from a third-party company without a complete sharing of knowledge, and which was introduced in 1928. the lenticular kodacolor was a three-color motion picture film made of a black and white reversal film coated on an embossed lenticular base, which requested 3 colored filters in red, green and blue during the exposure and the projection. it was quickly replaced by the kodachrome from 1935 on. the research odyssey of mannes and godowsky for the kodachrome between 1917 and 1935 has already been studied and partially documented by friedman (1944), collins (1990), coote (1993), brayer (1996) and le guern (2017, 2019). this paper will only point out some events and milestones of their research work and clarify how an important teamwork was necessary at kodak to work out a correct development process in 1935, and to simplify it 3 years later. 2. early attempts with the additive method of color reproduction the legend indicating that kodachrome was invented by two skilled musicians living far from science is wrong. mannes and godowsky were talented inventors who used a scientific background to transform the theory into a true process through experimentation. godowsky studied chemistry, physics and mathematics at the university of california and columbia university and mannes received his bachelor of science degree in physics from harvard in 1920 (brayer, 1996, p.224; george eastman house, 1964, p.15). the two men had met in high school in 1916 and became friends with a mutual interest in photography. the next year, mannes and godowsky saw in new york a film entitled our navy made with the prizma i additive process. the color rendering was not good and they started to undertake some research work at their high school to develop a better additive process. prizma i had been developed by william van doren kelley with the collaboration of charles raleigh, one of the inventor of the kinemacolor process. briefly, godowsky remembered in an interview in the 70s that our navy was a two-color process only. however, this additive process used a rotary filter made of 4 color filters combined in pairs of complementary colors, so we could also see this process as a 4-color one (dorot jewish division, 1971, p.39-40; layton and pierce, 2015, p.52-53). mannes and godowsky started by improving a parallax issue encountered with multiple lens systems. the effect of parallax occurred with color additive processes, when the spatial viewpoint of each lens to record a color was slightly offset from the viewpoints of the other lenses. therefore, the superimposition of the images was not optimal. they continued their research work during their holidays and managed to conceive a viable two-color additive process. it consisted of side-by-side images on a single strip of film exposed in a double-lens prototype camera. an experimental film was made but upon failing to adapt the projection equipment to the two-color film mannes and godowsky gave up their first color process (collins, 1990, p.206). when they graduated from university, they started to work full time as professional musicians but were still experimenting during their spare time on color processes. at the beginning of the 1920s, they progressively turned from the additive to the subtractive theory, considering rightfully that the multi-layer technology could be a better solution than a two-color or three-color additive process to develop a color motion picture film. in their makeshift laboratory at home, they managed to coat double-layered plates able to record part of the visible spectrum (brayer, 1996, p.225). but they also worked on the theory of threecolor photography and filed their first patent application in october 1921, to secure the making of a colored positive from a set of separation negatives (mannes and godowsky, 1925; friedman, 1944, p.108-109). evidence of a research work by mannes and godowsky on three-color photography has been found by the american artist matthew gamber in 2018. analyzing the industrial archive left by godowsky at the george eastman museum, gamber found photographic tests dated 1920 made with 3 the long-term development of three-color kodachrome. an odyssey from the additive to the subtractive method of color reproduction 26 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140103 separation negatives on black and white film using filters. he digitized each separation and combined the 3 files to create a final color photograph using an image processing software (gamber, 2019). the first photographic result was a view of the ansonia hotel in new york from mannes and godowsky’s apartment, where they installed a personal laboratory. the second image was a portrait of a young lady, identified by gamber as a cousin-in-law of mannes, the illustrator helen theresa damrosch tee-van, daughter of frank damrosch (fig. 1). this technique of three-color photography reminds us the process used by the russian photographer prokudine-gorski. the knowledge of this research work is useful because it confirms that in 1920, mannes and godowsky had not fully decided yet between the additive and the subtractive method of color reproduction. fig. 1. matthew gamber, three-color separation composite of helen damrosch tee-van, from a set preserved at the george eastman museum of three black and white negatives made by leopold godowsky and leopold mannes in new york city, ny, circa 1920. 3. the issue of funding and the progressive collaboration with kodak in the early 1920s, mannes and godowsky faced an important constraint. they had to seek funds to significantly improve their research work and results, as their families decided to stop their financing. in 1922, they were able to meet george eastman directly to present their work on color photography. eastman was intrigued by their findings, but the meeting had no financial results (brayer, 1996, p.225). finally, the two researchers managed to contact the photochemist kenneth mees who was the first director of the kodak research department. during one trip to new york, the intrigued mees met mannes and godowsky at the chemist’s club and was impressed by the progress of their photographic work. from then on and during the following years mees accepted to supply them with the materials they would need for their research, especially some experimental film coated with more than one emulsion layer on a transparent base, prepared according to their specifications, provided that the two leopolds would keep him informed of their further developments (james, 1990, p.166; mccarthy, 1987, p.10; brayer, 1996, p.225). the same year, mannes had also approached everett somers, a secretary of the investment firm of kuhn, loeb and company. the two inventors gave a demonstration of their experimental process and managed to get a twenty thousand dollar loan from the firm (strauss, 1962, p.97-98). the money was invested in the research and around one year later, mannes and godowsky filed another patent application for a two-color negative process (mannes and godowsky, 1924). a red-sensitive emulsion was coated on a transparent support, and an orthochromatic emulsion blue and green-sensitive was coated on the red-sensitive emulsion. after development and fixation this multi-layer film was treated with ferricyanide to convert metallic silver into silver ferrocyanide. the new feature of the patent consisted in the method used for the development of the ferrocyanide images: the diffusion into the gelatin of the solution used could be controlled at will. thus, one could develop only one layer without polluting the other one. mannes and godowsky took care not to unveil any formula or detailed mechanisms of this controlled diffusion (friedman, 1944, p.109-110). in 1925, the independent photochemist edward j. wall published his history of three-color photography and mannes and godowsky knew that they were cited in the book for their 1924 patent (wall, 1925, p.158). wall’s book was influential, because they learned for the first time the scientific narrative of the monopack film and the potential of color development from the use of color couplers, which were chemical substances able to form dyes (coote, 1993, p. 139). from 1925 on, mannes and godowsky decided to investigate the chemistry of color couplers and began working on a technology of integral tripack or monopack, which relates to a reversal multi-layer film made of three inseparable light-sensitive emulsion layers coated one on the long-term development of three-color kodachrome. an odyssey from the additive to the subtractive method of color reproduction 27 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140103 the other on a transparent flexible base. one such multilayer film was different than their initial two-layer negative process, which requested two different toning after the development to form the color in each layer. with wall’s book they read that a young independent photochemist karl schinzel was the first to patent the use of a subtractive monopack for color reproduction in 1905. in his process called katachromie schinzel suggested using a coated plate with several layers of silver bromide emulsion separated by plain gelatin films. each sensitive layer was colored complementary to its sensitivity. however, this innovative process was theoretical and the few dyes available were not satisfactory to allow its practical use (coote, 1993, p.134-135; friedman, 1944). in 1907, benno homolka from hoechst simplified schinzel’s process by inventing the principle of color development. he found that it was possible to form colored images by the creation of dyes in combination with silver images (coote, 1993, p.135). this discovery was finally patented by rudolph fischer and his colleague h. siegrist in 1912 with their method of color development anticipating the manufacturing of a subtractive tripack. for this process three emulsion layers were also coated on top of one another, and in each layer chemical dye-forming substances called color or dye couplers were incorporated. these dye couplers were supposed to form a dye image together with reduced silver into each emulsion layer in the presence of a developing agent. however, like schinzel or homolka, fischer was unable to realize his process in practice due to its complexity and to the poor stability of the dye-forming substances available in the 1910s. another issue was the impossibility to prevent the dye couplers from wandering between layers (coote, 1993, p. 139). from 1927 on, mannes and godowsky conceived a different strategy for the color development to get around this problem. unlike other methods, they decided to include the dye couplers into the liquid developer instead of each emulsion layer. thus, the wandering coupler problem would be solved, but not the similar issue of the wandering sensitizing dyes (james, 1990, p.166; collins, 1990, p.211). in 1928, the chemist of the kodak synthetic chemistry division leslie brooker was able to synthesize new dyes, which were excellent sensitizers from frances hamer’s research work (mees, 1961, p.121-123). the problem of wandering sensitizers was almost solved. the pooling of mannes, godowsky and brooker’s research works eventually constituted innovation because from that stage the monopack concept could move from theory to practice. for mees, the time to increase the scientific collaboration with mannes and godowsky had come: in 1930, i realized that the new dyes that we could now make would solve the problem of making mannes’ and godowsky’s proposed color process work. […] so we asked mannes and godowsky to join us here, where they worked happily with us for ten years, and we all set to work and made the new color process work (mees, 1955, p. 37). the agreement seemed an easy one. kodak offered to pay a lump sum of $30,000, annual salaries of $7,500 each and also agreed that mannes and godowsky would receive royalties on all patents filed before the collaboration with kodak (coote, 1993, p.139; collins, 1990, p.211). the two independent researchers accepted the offer and became incorporated in the kodak research organization in november 1930. first, they worked in a special laboratory at new york. after 1 june 1931, they started working at kodak park in rochester (kodak, 1930, p.4). finally employed by kodak, mannes and godowsky had to adapt their research methods to the collaborative work with the kodak research laboratory’s staff, because they were also known as professional musicians and had to prove their skills in photochemistry at the same time (kodak, 1989, p.51). however, this period is not well documented and it is difficult to ascertain the research work done and the practical terms of the collaboration. from 1930 on, the two inventors focused on processes involving mono-layer and mixed grain coatings to avoid the use of a multi-layer coating and its potential problems (coote, 1993, p.140). as mannes and godowsky had a three-year contract terminating at the end of 1933, and as the results of their research were not visible enough, mees had to insist with members of kodak management that they should be given another chance for one more year. they finally developed a concrete two-color motion picture film in 1934, “working practically around the clock, day after day” (james, 1990, p.166-167). as the production of the new film was delayed due to some complications, mannes and godowsky were able to perform additional research and modified the twocolor into a three-color process. 4. market launch of a three-color film not yet finalized in 1935 finally, the new kodachrome process in its 16mm version for color movie was announced in april 1935. as the motion picture film consisted of five layers of emulsion and gelatin it was nicknamed the “quintuplet” film by science magazine (anon, 1935). three layers were devoted to the recording of the blue, green and red spectrums. between each sensitive layer a thin layer of clear gelatin was coated, used as a margin of safety during the development process and the use of the controlled diffusion bleach (fig. 2). it was thus possible to bleach two layers and not the the long-term development of three-color kodachrome. an odyssey from the additive to the subtractive method of color reproduction 28 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140103 bottom layer. nevertheless, the first development process was very long and involved in all 28 steps (coote, 1993, p.142; coe, 1978, p.128). however, the correct development processing for the new kodachrome film was not at all ready in april 1935. this situation was critical. it was possible to expose some 16mm kodachrome reels but it was still impossible to get a neutral colorimetric rendering of the developed slides. mees had to organize and supervise an exceptional program in extreme circumstances; the theoretical technology of kodachrome had to confront the practical side of the laboratory (le guern, 2017, p.264-265). fig. 2. drawings from the american patent us 2113329a « color photography » filed by mannes and godowsky on 27 february 1935 and granted on 5 april 1938 (espacenet, european patent office). in one of his notebooks, the researcher franck b. phillips detailed this critical period of intense research for a satisfactory development process. phillips, a member of the harrow research laboratory, was already visiting and working at rochester in november 1934. he had probably been requested to help the american scientists and assist mannes and godowsky. in april and may 1935, he was testifying to the intensive work undertaken in the research laboratories. the teams were working nearly all day long with infrequent breaks in a desperate quest for better kodachrome processing (phillips, 1935). on may 10th, phillips noted that “a man (pringle) was sent to the medical dept having been made sick with fumes from acetonealcohol mixture while cleaning racks from the b-g developer” (phillips, 1935, p.71). one day, phillips reported that the general tendency of the experimental work was the development of kodachrome with green neutrals. the photochemists tested several solutions to reduce the color cast but, as the writer noted, the "results were very erratic" (14 may 1935, p.75). some days later, the situation was better and the developed kodachrome motion picture films at last reached a correct neutrality in the grey. the magenta bleach had been acidified with hydrochloric acid to reduce the residual blue-green dye. this acidification was criticized by godowsky but phillips disagreed in his notebook (phillips, 1935, p.79). this evidence of research teamwork illustrates well the complexity of the new kodachrome process. 5. chemical stability and color rendition of three -color kodachrome version 1935-1938 regarding this first version of kodachrome film, it is challenging to estimate their photographic characteristic such as color rendition or stability of dyes owing to their scarcity in the early 2020s (fig. 3). sylvie pénichon recently pointed out that original kodachrome transparencies should not be projected due to their poor stability to light (pénichon, 2013, p.204). louis w. sipley, a photographer and the creator of the american museum of photography in philadelphia, included in his 1951 book valuable information about the stability of kodachrome: the dyes in this earliest kodachromes were not very stable, with the result that pictures made on the 1935 film have degraded and no longer retain the full colors as originally made. just as this book go to press [so we were in 1951] the american museum of photography has been presented with several rolls of 16mm kodachrome motion pictures made in 1935 which show almost monochromatic pictures of a purple-magenta character (sipley, 1951, p.142). this clue points out that the yellow and cyan dyes in particular were less stable in the kodachrome sandwich made and developed in 1935. motion picture and still film rolls in color made during the period 1935-1938 are really rare or difficult to identify in the institutions preserving film heritage such as national or private archives and museums. the long-term development of three-color kodachrome. an odyssey from the additive to the subtractive method of color reproduction 29 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140103 fig. 3. the first version of three-color kodachrome was introduced in 1935 as a 16mm movie film, and as a 35mm film for still cameras in 1936 (eastman kodak company, 1971, p. 13). however, a short film made in 1937 by the well-known photographer man ray provides some information about the nature of kodachrome color rendering. according to man ray, he received a large quantity of kodachrome rolls to test and a 16mm camera from the british subsidiary of kodak in london (man ray, 1963, p.293-294). the result was a short film named “la garoupe”, more than 10’ long, some portions of which were recently shown in a french documentary named “un été à la garoupe” (knowles, 2012, p.239-240; lévy-kuentz, 2020). the competition with kodachrome was tough. in 1936, the i.g. farbenindustrie a.g. at wolfen in germany managed to develop a technology of anchoring color couplers to individual emulsion layers, with the use of long-chain molecular structures. this way, a process of selective color development by controlled diffusion used by mannes and godowsky, was no longer necessary. the color couplers could be incorporated into the monopack film, and not during the developing process of the exposed film. finally, after a satisfying selection of couplers for each of the three layers, agfa introduced in october 1936 the agfacolor neu film including a simplified multi-layer reversal technology (flueckiger, 2012). this innovation into the field of the monopack film led mannes, godowsky and their colleagues at the kodak research laboratories to optimize the kodachrome process. 6. the necessary simplification of the three-color kodachrome developing process for kodak, the elegant solution of the agfacolor neu was a technological and economical threat even if the color rendering of the kodachrome film was slightly better. the technology used by agfa was far simpler and rendered the 28 steps necessary to the processing of kodachrome films obsolete. the need of improving the stability of the chemical dyes used in the layers of kodachrome was another important fact. kodak’s first action was to develop a simpler processing for the kodachrome films. it was not before 1938 that they released this new processing. the controlled diffusion bleach was replaced with selective reexposure for each color-development step. in this way the total number of steps was reduced to 18 (kodak, 1989, p.52). the long-term development of three-color kodachrome. an odyssey from the additive to the subtractive method of color reproduction 30 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140103 fig. 4. first kodachrome developing process (1935-1938) compared with new kodachrome developing process (from 1938) in weissberger (1970). lot spaulding wilder, a researcher of the rochester laboratory, was the inventor of the kodachrome processing simplification (james, 1990, p.169). after the release of the kodachrome monopack, mees decided to create an experimental department for color photography including wilder, ralph m. evans and wesley t. hanson. mannes and godowsky also played an important role for scientific and patent work during the period up to the outbreak of the second world war. the final process was described by friedman (1944, p.122). the new processing was equivalent up to the exposure with red light and the development in cyan developer (fig. 4). the next step was to expose the blue sensitive layer from the top of the film with a blue light, and to develop with a yellow-coupler developer. then the middle layer magenta sensitive was exposed to white light or treated by a fogging agent such as methylene blue or thiourea. this layer was developed with a magentacoupler developer and the rest of the processing was similar to wilder’s experimental process of february 1938. the move from theory to production was unsurprisingly tough, as confirmed by mees in 1944: this process offered very considerable difficulties when it was first attempted but, in view of its advantages, they were overcome, and it is the method by which the kodachrome film is now processed (mees, 1944, p.234). following the successful simplification of the kodachrome developing process, mannes ceased his collaboration with kodak in 1939. the same year, godowsky left the kodak research laboratory but still worked on color photography as a consultant in a small personal laboratory in westport, connecticut, nicknamed “kodak park westport” (kodak, 1989, p.54). after the second world war, the knowledge produced and mastered on color technology would lead to other kodak processes, such as kodacolor negative film, ektachrome reversal film and eastman color negative. 7. conclusion this paper attempted to outline how the introduction of the 16mm version of kodachrome in 1935 was only the beginning of kodak research on color technology. it was only made possible with the long-term collaborative work the long-term development of three-color kodachrome. an odyssey from the additive to the subtractive method of color reproduction 31 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140103 with the atypical photochemists mannes and godowsky and the researchers of the kodak research laboratories. in 1917, mannes and godowsky began studying independently the technology of color additive processes in the quest for a motion picture film in color. in the early 1920s, they managed to create a scientific collaboration with kodak and be funded by kuhn, loeb and company. mannes and godowsky gave up the additive method and investigated the concept of subtractive multi-layer film involving a color development from 1925 on. they were employed by kodak and incorporated in the research laboratories in 1931, and managed to develop the threecolor kodachrome, a motion picture film in 1935. the introduction by agfa of the three-color agfacolor neu film led mannes, godowsky and the kodak researchers to simplify the kodachrome developing process in 1938. 8. conflict of interest declaration the author declares that there is no conflict of interest related to this publication. there are no actual or potential conflicts of interest, including financial, personal or other relationships with other people or organizations. 9. funding source declaration this research was carried out without external funds. 10. acknowledgment the author wish to thank bertrand lavédrine for his kind suggestion to submit a paper proposal at the conference color photography and film (…) organised by gruppo del colore – associazione italiana colore, and matthew gamber for his useful information about the leopold godowsky’s archive at the george eastman museum and the sharing of his digital reproductions of some experimental processes and emulsions. 11. short biography of the author nicolas le guern, ph.d., is a technical manager in the photographic industry and a regular lecturer in french universities. his thesis completed in 2017 (phrc – dmu) is about the organization of kodak research in europe. his research interests include the industrial research on photographic and cinematographic color processes and the circulation of 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(1970) ‘a chemist's view of color photography: how does color photography work? what is required of the light-sensitive material? what is the origin of the image dyes?’, american scientist, 58(6), p. 651. https://www.lemonde.fr/culture/article/2020/11/28/un-ete-a-la-garoupe-dans-l-intimite-surrealiste-de-pablo-picasso-dora-maar-et-leurs-amis_6061512_3246.html https://www.lemonde.fr/culture/article/2020/11/28/un-ete-a-la-garoupe-dans-l-intimite-surrealiste-de-pablo-picasso-dora-maar-et-leurs-amis_6061512_3246.html https://www.lemonde.fr/culture/article/2020/11/28/un-ete-a-la-garoupe-dans-l-intimite-surrealiste-de-pablo-picasso-dora-maar-et-leurs-amis_6061512_3246.html 94 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140112 is a house named “yellow” really yellow? survey on the perception and naming of the yellow color on building facades depending on its hue, lightness and saturation justyna tarajko-kowalska cracow university of technology, faculty of architecture, poland, justarajko@tlen.pl abstract the article's primary goal is to present the author's online color survey results. the study was aimed at checking which colors chosen from ncs color system's four yellowish hue groups: g80y, g90y, y, and y10r are considered as "yellow." the 28 nuances differed in hue, lightness, and chroma, were presented separately on color swatches and building facades. at first, the respondents assessed the yellowness of selected colors and then indicated the most appropriate ones for the color term "yellow." the analysis of the 444 results confirmed the high importance of saturation and lightness (whiteness/blackness level) in color appearance and naming. the research proved that a given color is likely described as "yellow" only when its parameters of lightness and saturation are similar to the prototype of the yellow color category, characterized by high saturation and high intrinsic lightness. the clarity of the hue was also the significant factor. keywords yellow, color in architecture, color attributes, color naming, color appearance, color perception received 06/11/2021; revised 03/12/2021; accepted 05/04/2022 is a house named “yellow” really yellow? survey on the perception and naming of the yellow color on building facades depending on its hue, lightness and saturation 95 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140112 1. introduction the yellow color has been common in architecture since the earliest times. for ages the rationale and ways for using this hue in built environment were diverse, but it was always present in many varieties due to its positive connotations with sun, light and metal gold, as well as the popularity and availability of ochre pigments. yellow ochre was not only the oldest yellow pigment but also one of the first pigments ever used by humans. thus, warm, orangey yellows were and still are shaping the chromatic perception of many towns and villages around the world. in contemporary built environment, yellow plays an important role in the city visual communication system and corporate identity, being also common color of mailboxes, taxis and tramways. thanks to new materials and technologies, highly saturated yellow as a visual attractor appears both in public buildings and spaces, being modern and an intriguing color in architecture (tarajko-kowalska 2021). many research confirms (e.g. janssens and küller, 2009), that yellowish hues from groups: yr (yellow-red), y (yellow), and gy (green-yellow), according to the ncs – natural color system nomenclature, are constantly most preferable for residential buildings facades in many countries, especially in europe. but, compared to the other primary colors, pure yellow occurs only in a narrow band of the spectrum with a wavelength of 570–580 nm (lancaster, 1996). varieties of yellow may differ in one, two, or three of the color attributes: hue, lightness and saturation (chroma), thus creating a full spectrum of tones and shades. in the environment many yellowish tones exist, as it “can tend toward green on the one hand and toward orange on the other”, being described as color of gold, lemon, sulphur and saffron (pastoreau, 2019). this richness of nuances can be represented for example by latin vocabulary, where the most frequently used adjective flavus describes saturated yellow, while fulvus means darker yellow, croceus saffron orangish yellow, luteus is used for ordinary yellows present in flora and fauna, aureus represents gold, luridus grayish yellow etc. (pastoreau, 2019). in residential architecture yellows are usually used in pastel tones with high lightness level, in muted shades with low chroma, or as earthy browns. so the question arises: is a house colored yellow really perceived as yellow? because in most cases very dark or very pale tones cease to appear yellow anymore. also, the latest studies on color-emotion relations confirm that less saturated and darker yellows do not even produce the same emotional reactions as highly saturated ones (e.g. schloss et al., 2020). the same conclusion comes from the author’s recent study on the use of the yellow color in architecture and built environment, where only those examples in which highly saturated tones were used, seem to carry all the characteristics and associations assigned to the yellow color, considering its symbolic, functional, and decorative aspects (tarajko-kowalska, 2021). while thinking or reading about the "yellow building", don’t we imagine a brightly colored house, clearly visible in the landscape or being a visual attraction in public space? those findings and questions led the author to research which samples and building facades, colored in yellowish hues, different in the attributes of lightness and saturation, are still considered as “yellow”. the main purpose of the article is to present the results of this color survey [1]. 2. method to conduct the research, an online questionnaire was prepared in google forms. the main reason for choosing this form of survey was the author’s desire to obtain as many results as possible, with participants' minimal workload. the study was also meant to be entertaining for participants so that the responses obtained were not forced but reflected the real observers' opinions. 2.1 survey structure the study consisted of three parts. the first part was dedicated to collect the respondents' data. participants reported their gender (female/male) and age (<18, 18-29, 30-39, 40-49, 50-60, >60). they were also asked to specify the level of their experience with color (none, basic, middle, or advanced) and give the information if their proper color vision was confirmed by a medical examination for driving license and/or any color tests. it was also possible to make quick tests online while filling the survey, by clicking the given links to the ishihara test (http://colorvisiontesting.com/ishihara.htm) and x-rite test (https://www.xrite.com/hue-test). in the second part, participants were rating on a scale from 1 to 5 (1 – definitely not, 2 – rather not, 3 – not sure, 4 – rather yes, 5 – definitely yes) if randomly presented color samples can be considered "yellow" (figure 1). after that, responders were asked to indicate three color samples (from all twenty eight color samples seen before) they think are most adequate for the color term "yellow". the third part of the study was dedicated to building facades (figure 2). similarly to previous part, the respondents were asked at first to rate on a scale from 1 to 5 the level of "yellowness" of the presented building façade, which was computer-painted in one of the twenty eight selected colors same as color swatches seen before. after finishing, they chose three facades, which is a house named “yellow” really yellow? survey on the perception and naming of the yellow color on building facades depending on its hue, lightness and saturation 96 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140112 colors they consider the most appropriate for the term "yellow". on average, to complete the survey took around 10-15 minutes. fig. 1. general appearance of the questionnaire for color sample (question: do you think, that the presented color sample can be considered “yellow”?) fig. 2. general appearance of the questionnaire for building façade (question: do you think, that the presented building facade can be considered “yellow”?) 2.2 colors selection in order to conduct the survey, 28 colors, differing in hue, lightness (whiteness/blackness level) and saturation (chromaticness), were specified, then used to color the samples and facade of the selected building. the colors used in the survey have been chosen from ncs color system’s four yellowish color groups: g80y, g90y, y, and y10r. the y20r group was also considered, but due to strong orange appearance of the nuances it was finally rejected in favour of the g80y group. authors’ wish was to represent all the color families: pastel (high lightness and chroma), pale (high lightness and low chroma), vivid (highly saturated), rich (low lightness and high chroma) and finally dull (low lightness and low chroma). however, due to the fact that selected colors were to be presented also on the building façade, very dark and highly saturated colors have been eliminated from the list. another limiting element was the number of samples for presentation. finally, seven nuances were selected from each hue group to represent the colors that often appear on the facades of residential buildings: 0515, 0530, 0550, 1015, 1040, 2030, 3010. the author made the choice based on her experience as an architect-designer and on the knowledge of the color palettes offered by various manufacturers of facade paints and plasters. the ncs triangle was used to provide the same nuance for samples from particular hues (figure 3). fig. 3. selection of the colors to the survey; a. ncs triangle with position of the 7 selected nuances and ncs circle with selected hue groups: g80y, g90y, y, y10r; is a house named “yellow” really yellow? survey on the perception and naming of the yellow color on building facades depending on its hue, lightness and saturation 97 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140112 b. table with selected nuances and their parameters: s blackness (aa), c chromaticness (bb), w – whiteness, v – lightness, m – saturation. as the color samples were to be presented online, to reflect the colors of a specific notation, the ncs colourpin application was used, which ensures a high degree of compatibility between the appearance of the physical ncs colour samples and the one presented on the displays of electronic devices. of course, the author realizes that in the case of patches showed online accurate color presentation cannot be fully ensured. however, in the case of the conducted research, the perfect match of the appearance between the physical samples and the one visible on the screen was not the highest priority and in the author's opinion it did not significantly affect the obtained results. 2.3. building selection for the rating of “yellowness” level of the facades, njálsgata house in rejkjavik on iceland was chosen (figure 4). this residential building from early 20th century undergone in 2015 contemporary refurbishment and reorganisation by krads architects (https://www.archdaily.com/923370/njalsgata-housekrads). the building was selected mostly because its form and style can easily accept different shades and tones of yellowish hues. the house has also gray roof and neutral, almost achromatic neighborhood, which reduced possible influence of adjacent chromatic colors on the perception. for the same reason the photo was taken on a cloudy day, to avoid sun contrasts and shades, which could affect final color appearance. fig.4. façade of njálsgata house in rejkjavik on iceland selected for the presentation of colors in survey. 3. results the results of the study were presented and analyzed in two ways. the first part consists of the outcomes of “the yellowness” assessment of the individual 28 colors. those results were presented in individual column charts for each of the 28 swatches and facades, generated automatically in google forms, and then the summary graphs for each hue group (g80y, g90y, y, y10r) were created by author. the second part contains the results of the color selection most appropriate for the term "yellow." these effects were presented as horizontal bar charts (also generated in google forms program) ranked from the nuances most frequently chosen to those with the slightest indications.[2] 3.1 participants the author collected the data presented in this article in may 2021 for around one month. during that period, 444 participants took part in it, 332 females (74,9%) and 112 males (25,1%). they were primarily polish students and academic teachers from the cracow university of technology, faculty of architecture, but also students of industrial design from the cracow academy of fine arts and others. more than half were in the age range 18-29 (53,3%). next age group was 40-49 and 30-39 range with about 16% each. there were also some participants in the age range 50-60 (8%) and over 60 (4.7%), as well as few in age less than 18 (1,3%). only 21% of the participants do not have any confirmation for their proper color vision besides their declarations. most of the respondents (90,4%) declared some experience with color (basic – 28,1%, middle – 38%, advanced24,3%). detailed participants data are presented in table 1. table 1. survey participants statistics data is a house named “yellow” really yellow? survey on the perception and naming of the yellow color on building facades depending on its hue, lightness and saturation 98 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140112 3.2 results of part i – the assessment of yellowness of individual colors appearance on swatches and building facades in the rating if presented color can be considered "yellow" (at first assessed on swatches, then on facades), the highest unanimity and percentage of "yes" responses (percentage shown together for answers 5 “definitely yes” and 4 “rather yes”) was achieved by the nuance 0550 (highest saturation/lightness, lowest whiteness). the undisputed number one became color 0550-y with the “yes” results equal 96.2% for sample and 98.2% for facade. the colors 0550-g90y and 0550-y10r achieved only slightly worse results, with the percentage of "yes" indications consistently higher for the facades (93,9%, 91,2%) than for the swatches (83,8%, 84,2%). for the 0550-g80y nuance, a high level of the consensus occurred only for the elevation (82% to "yes"), while for sample over 50% of the responses were negative. the highest percentage of "no" responses concerns the nuance 3010 (lowest saturation/lightness, highest blackness), which for all hues was not perceived as yellow either for the color swatches or the facades in more than 90% (in most cases, the percentage of the summed up answers 2 "rather no" and 1 "definitely not" reached 98.9% for samples and 95% for facades). also for the 1015 nuance (low saturation, high whiteness), the negative responses dominated in the case of samples, changing slightly together with the hue from g80y to y10r (97.1% 74.1% 75.8% 80.8%). in the case of facades, the responses were very diverse, except for the hue g80y with 72% to "no." there was a slight "yes" tendency for hues g90y and y (53.5% -49.2%), but for y10r the numbers of "yes" and "no" responses were nearly even. the nuance of 2030 (average level of saturation/lightness, lowest whiteness) brought interesting results, as it existed a discrepancy in its perception between swatches and facades. there was a high percentage of the "no" answers for the samples, slowly decreasing while changing the hue (94.5% -93.5% -85.3% -77.2%). in the case of the facades, the situation was different. while for greenish yellows g80y and g90y, the percentage of negative responses was still significant (71.6% -52.3%), for hues y and y10r there were more responses to "yes" (51.9% 68.2%). in the case of the 1040 nuance (high saturation, average blackness/lightness), the hue also played a significant role. only for the y there was a high "yes" percentage for both the samples (81%) and the facades (97%). y10r hue has still high "yes" responsiveness for facades (80%), while for samples it was only 60%. for the greenish yellows of g90y, there was still a high percentage of "yes" responses to facades (74%), but "no" responses began to dominate in the swatches (42.5%). for the g80y, the "no" responses predominate for both the samples (80%) and the facades, although here to a lesser extent (60%). in the case of the 0530 nuance (highest lightness, middle saturation, lowest blackness), full agreement of the "yes" responses occurred for the hues g90y and y, with a higher percentage observed for the facades (96%, 92%) than for the samples (77%, 72%). at the y10r hue, a large variation in the results for the swatches was observed, together with a slight dominance of the "yes" answers for the facades (60.5%). for the g80y, there was a full discrepancy in the responses, with 65% "no" for the samples and 58% "yes" for the facades. for the 0515 nuance (highest lightness/whiteness, low saturation), there was also a dissimilarity of opinions between the samples and facades assessment. here, too, the hue played a decisive role. for the swatches, the responses were mostly negative, with the percentage of "no" gradually decreasing with the hue change from g80y to y10r (89%-69% -50.4% -49%). for the facades, with the change of the hue, the number of positive responses increased from 49% to "no" for the g80y to 61% to "yes" for the shade y10r. detailed results of part i of the survey are presented in table 2. table 2. results of part i. yellow color appearance (perception) on color samples (s) and on building facades (f) in %. 1-definitely not, 2-rather not, 3-not sure, 4-rather yes, 5 -definitely yes. 3.3. results of part ii – the best examples of the yellow color on swatches and building facades the color 0550-y was found to be the most appropriate for the term "yellow" for both the swatches (93,4%) and the facades (80.8%). among the presented samples, it was is a house named “yellow” really yellow? survey on the perception and naming of the yellow color on building facades depending on its hue, lightness and saturation 99 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140112 the color with the highest level of both saturation and lightness. it also has no admixture of other primary colors (it is neither reddish nor greenish). thus, it can be treated as a "unique hue" and the most similar color to the typical representative for the yellow color category (see witzel, 2018, schloss et al., 2020). the colors 0550-y10r (71% for samples and 48.5% for facades) and 0550-g90y (52.7% for samples and 63% for facades) were second. also, these colors are characterized by the highest saturation and lightness, but their hues have slight admixtures of red and green, respectively. the remaining color 0550-g80y in this nuance came in a relatively high fifth place for facades (26.9%), but for the samples, it was in the ninth position with only 4.1% of the response. the next places were colors: 1040-y, 0530-y, and 0530g90y. a small percentage of the answers were also given to the nuances 1040 and 0530 for the y10r hue, and in the case of the facades also for the g80y. the nuance 3010 was not indicated even once for any of the hues. neither for the samples nor the facades were indicated colors having both a high degree of whiteness and low saturation (0515, 1015) or low saturation and low lightness (3010). thus, saturation was the decisive parameter in that case. for colors with an average saturation level (0.35, 0.37) lightness and blackness were the decisive parameters. the darker nuance 2030 (brightness 0.8) was not indicated at all, while the lighter 0530 (brightness 0.95) was ranked relatively high for hues y (28.5% samples) and g90y (20.5% facades) (see detailes on figure 5). fig 5. results of part ii color swatches and building facades considered as most suitable for term “yellow”. ranking list of top 9 nuances for swatches (a) and 14 (b) nuances for facades. 4. conclusion and discussion the analysis of the results confirmed, also emphasized by other researchers (e.g., witzel, 2018, witzel et al., 2019, schloss et al., 2020, divers, 2021), the importance of saturation and lightness (the degree of whiteness/ blackness) in colors appearance and naming. the attribute of saturation was the most significant when indicating adequate colors for the term "yellow" (the higher the chroma, the more often the color was chosen). next, the decisive parameter was the degree of whiteness and blackness colors with a high blackness or whiteness were rarely indicated as "yellow." the research proved that a given color is likely described as "yellow" only when its parameters of lightness and saturation are similar to the prototype of the yellow color category, characterized by high saturation and high intrinsic lightness (schloss et al., 2020). color appearance is also typically assessed by reference to one of the unique hues (witzel, 2018). that explains why the most frequently indicated was the purest hue y, then y10r and g90y, and least often g80y. the clarity of the hue was the decisive factor, especially in the case of both highly saturated and whitened colors. it seems that the confidence of indicating "no" increased with dark and low saturated colors because both parameters are different from the typical yellow prototype mentioned previously. in addition, dark yellows cross the color category from "yellow" to "brown" (schloss et al., 2020), and the hues of g90y and g80y visually turn green. in the comments to the survey, the respondents assessed the survey as giving "fun" but at the same time causing confusion and raising deep doubts about the nomenclature and definition of colors with variable saturation and lightness, and what can still be called "yellow" and what not. so, there is a need to go beyond the basic color categories in the scientific research, as they do not cover the whole variability of perceived color "subcategories", depended its parameters (in case of yellowish hues this will be, e.g., when lighter: beige, darker: brown, greener: lime, redder: ochre, orange, see figure 6). this can be achieved by extending (but not replacing) the "hue paradigm" with the "value-chroma paradigm" (see divers, 2021). this is important particularly in environmental color design as the vast majority of nuances present in natural surroundings are not highly saturated. the research also reveals that various nuances are more likely declared "yellow" on the façades than on the samples. this is especially evident when the swatches were rated as not yellow while the facades were still placed in the yellow category. it is known that color is perceived differently on the sample than on the facade. is a house named “yellow” really yellow? survey on the perception and naming of the yellow color on building facades depending on its hue, lightness and saturation 100 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140112 however, the reason for these discrepancies may also be that the color of the sample is evaluated strongly by reference to the typical yellow prototype. in contrast, for the facade, observers base their judgment more on experience and cultural traditions. thus, the color tests and color choices, which concern particular objects (such as buildings), should not be performed only on color samples, as they may give completely different, even opposite results. those findings may be a starting point for a wider discussion on the actual preferences of yellowish colors for building facades and the way of describing them in the context of not only the hues but also, perhaps even above all, their lightness and saturation. fig 6. potential yellow color "subcategories", depended on the parameters of hue, lightness and saturation. conflict of interest declaration the author declares, that nothing has affected her objectivity or independence in the production of this work. there are no actual or potential conflicts of interest, including financial, personal or other relationships with other people or organizations, that could inappropriately influence (or be perceived to influence) this work. funding source declaration this research did not receive any specific grant from funding agencies in the public, commercial, or not-forprofit sectors. acknowledgment the author would like to express sincere thanks to all those (especially students), who volunteered for the online survey and completed the questionnaire. short biography of the author justyna tarajko kowalska phd. architect, lecturer at the cracow university of technology, faculty of architecture. author of over 60 articles on the topic of color in architecture, published in polish and english. in scientific studies, she concentrates especially on the issue of color in the built environment, as well as the history of color in architecture and space. notes [1] the idea to carry out this survey was born during the author's research on the color yellow in architecture and the built environment, the results of which were presented in the article entitled ‘yellow color in european architecture and built environment: traditions and contemporary application’ (tarajko-kowalska, 2021). for that reason, presented study is of a more technical nature and the author intentionally does not mention the cultural background of the use of yellow, which was described in detail in the paper mentioned above. [2] supplementary data to this article with detailed results of the study presented on diagrams can be found online at: https://drive.google.com/drive/folders/1f5efcwpu3f_moaadmp1vvw idbp0oybo2?usp=sharing references divers, e. (2021) ‘beyond hue: the affective response to value and chroma’, in: griber, y.a. and schindler, v. m., (eds) the international scientific conference of the color society of russia: selected papers, smolensk: smolensk state university press, pp.154-159. janssens, j., and küller, r. (2009) ‘preferences on colors on buildings’, in: t. porter, t. and b. mikellides, b. (eds) color for architecture today. london: taylor and francis, pp.124–127. lancaster, m. (1996) colorscape. london: academy editions. pastoureau, m. (2019) yellow: the history of a color. princeton: princeton university press. schloss, k., witzel, ch. and lai. l.y. (2020) ‘blue hues don’t bring the blues: questioning conventional notions of color-emotion associations’, journal of the optical society of america a, vol.37/no.5. pp. 813-824. doi: 10.1364/josaa.383588 tarajko-kowalska, j. (2021) ‘yellow color in european architecture and built environment: traditions and contemporary application’, in: griber, y.a. and schindler, v. m., (eds) the international scientific conference of the color society of russia: selected papers, smolensk: smolensk state university press, pp. 319-324. witzel, ch. (2018) ‘the role of saturation in colour naming and colour appearance’ in: l. macdonald, l., biggam, c.and paramei, g. ed., progress in colour studies. cognition, language and beyond, john benjamins publishing company. pp. 41–58. witzel, ch., maule, j., and franklin, a.. (2019) ‘red, yellow, green, and blue are not particularly colorful’, journal of vision 19(14):27. pp. 1-26. doi: 10.1167/19.1 https://drive.google.com/drive/folders/1f5efcwpu3f_moaadmp1vvwidbp0oybo2?usp=sharing https://drive.google.com/drive/folders/1f5efcwpu3f_moaadmp1vvwidbp0oybo2?usp=sharing 14 color culture and science journal vol. 13 (1) doi: 10.23738/ccsj.130102 bramante and his work of painted façades: bergamo and lombardy patrizia falzone 1 1 department dad, scuola politecnica, genova, italy. pa.falzone@gmail.com abstract bramante, a renowned architect of the high renaissance, is not well known for the remarkable paintings that constitute his artistic beginning, education, and development in the wake of piero della francesca, of melozzo and of mantegna, as well as paolo uccello and others from the circle of urbino. his painted architectural illusions, which create complex and articulated spaces, make him a fundamental figure in the fifteenth century in lombardy. in fact, moving from urbino to milan, he brought there the renewal that was developed by the urbino circle, which was a humanistic centre of primary importance since the mid-fifteenth century. here “on the basis of the teachings of piero della francesca … and not without some knowledge of mantegna, a school of ‘perspective architects’ must have been formed” – with architects, architectural designers and painters working together. in any case, the culture of urbino and the paduan-mantegnesque culture are at the basis of donato’s education (bruschi, 1985). keywords color, painted façades, architecture, urban environment, bramante received 16/01/2021; revised 26/01/2021; accepted 28/03/2021 bramante and his work of painted façades: bergamo and lombardy 15 color culture and science journal vol. 13 (1) doi: 10.23738/ccsj.130102 1. introduction within the decades-long field of study of painted façades of historical architecture, and of the relationship between painted façades and architecture, the specific theme of bramante’s activity as a painter of façades is here addressed. the aim is to spread this fundamental part of his work widely and to develop it as it deserves (falzone, 2020). this part of his production, in fact, is not very well known, when compared with his great fame as an architect. indeed, the theme of his several façade frescoes, mostly in lombardy, is not much dealt with, nor diffused among non-experts: perhaps because this heritage is little preserved in situ, and only partially musealized. in this paper, in particular, the chromatic values of his two most important and remarkable façades are analyzed: 1. the façade of palazzo del podestà in bergamo, whose detached fresco portions are preserved in the museo delle storie di bergamo, in palazzo della ragione. the theme is that of the “ancient philosophers”, which are painted between the openings. unfortunately, the preserved parts are very incomplete. 2. the frescoes on the walls of the hall of casa panigarola in milan, in piazza dei mercanti, now detached and preserved in the pinacoteca di brera. these are particularly interesting and meaningful since in them all the figures, which represent men-at-arms, are preserved, two in their entirety and the others from the waist up. in addition to these two most important examples, of which the chromatic characteristics are analyzed, the features of other bramantesque façades are cited and described: 3. casa angelini in bergamo, with a polychrome fresco on its façade and painted stories in venetian style. 4. casa bottigella in pavia, whose façades on the court are frescoed with renaissance grotesques. 5. the porticoed façades on the square of vigevano, decorated with the repeated motif of the candelabra. 6. the façade of palazzo fontana silvestri in milan, corso venezia, painted with a double order decoration in renaissance style. bramante’s pictorial work emerges clearly in the main renaissance treatises of the fifteenth centuries: those of l. b. alberti (alberti, 1436), francesco di giorgio martini, piero della francesca and antonio averlino “filarete”. while, in the sixteenth century, it is visible in that of sebastiano serlio (serlio, 1537), giacomo barozzi da vignola, giovanni paolo lomazzo, vincenzo scamozzi, andrea palladio and others, as well as vasari’s vite – vita di d. bramante (vasari, 1568). in modern times, andrea bruschi is the italian scholar of bramante that explored the most his entire production, including his work on façades, through his several publications: (bruschi, 1971), (bruschi 1973) and (bruschi, 1985). recently, in 2018, the conference “bramante a bergamo e la città a colori” was held in bergamo. it was aimed at rediscovering the city, that was once all painted, and bramante’s façades in bergamo (ferrari, 1964). here, instead, the overall typological, compositional, and chromatic analysis of his façades production in lombardy is developed, through what has been preserved. bramante was born in monte asdrualdo, near urbino, in 1444. he earned his education in the artistic environment of urbino, at the montefeltro court, but he carried out his production mostly in milan and rome. in fact, bramante moved from urbino to milan, at the court of ludovico il moro, between 1477-1479, where he worked from about 1479 to 1499 (malaguzzi valeri, 1915), (beltrami, 1901), and then moved to rome, where he worked from 1499 to 1514 (longhi, 1955). piero della francesca and melozzo da forlì’s influences, as well as the acquaintance of mantegna, emerge from the frescoes that are preserved in palazzo del podestà in bergamo, and even more from the frescoes of casa panigarola at milan. here, melozzo and mantegna’s suggestions are recognized in the layout used for the monumental figures. these are painted using a view from below, with a conception of spatial illusion that is new to the fifteenth century. the recurring chromatic values are few but intense, and show “his particular sensitivity for coloristic and atmospheric values” (bruschi, 1985). moreover, according to bruschi, bramante is also sensitive to what was already being made in lombardy by filarete, michelozzo, foppa (cappella portinari in sant’eustorgio), and amadeo (cappella colleoni). this pictorial heritage stands out for its distinct architectural component. in fact, the frescoes façades and building interiors always show the strong architectural-perspective suggestions derived from his education in urbino. 2. the main fresco façades in bergamo in 1477, on behalf of podestà badoer, bramante worked on frescoing the façade of palazzo del podestà, in bergamo. here, he painted “melozzesque” and monumental figures of “ancient philosophers” (bruschi, 1985). this theme was recommended by filarete in his bramante and his work of painted façades: bergamo and lombardy 16 color culture and science journal vol. 13 (1) doi: 10.23738/ccsj.130102 1460 treatise (averlino, 1460), as described by michiel in 1525: “li phylosophi coloriti nella fazzada sopra la piazza et li altri phylosophi de chiaro et de scuro verdi nella sala furono de man de donato bramante...” (i.e. “the colorful philosophers in the façade above the square and the others philosophers painted with a green chiaroscuro in the hall were created by donato bramante”) (michiel, 1525). he uses both polychromy, in the exterior, and monochromy, in green, in the interior hall. green, within an overall analysis, is one of the colors he uses most frequently, and it refers to one of the masters of early renaissance, paolo uccello. the latter in fact, a perspective virtuoso, frescoed the equestrian monument to giovanni acuto in florence cathedral in green monochrome; the large lunette with “flood and stories of noah” in the chiostro verde at santa maria novella in 1448; the “stories of saint monks” in the cloister of san miniato al monte using vibrant colors, with figures in green monochrome and scenes framed by pillars (fig.1). fig. 1.the frescoes by paolo uccello in the upper loggia of the cloister of san miniato al monte. vasari wrote: “he painted in san miniato, in a cloister, in green umber and partly colored, the life of the holy fathers, in which he did not observe very much the solution of using a single color, as stories should be painted, since he colored in blue the backgrounds, in red the cities, and the edifices in more colors, according to his will…”. photographs by the author. on the façade of palazzo del podestà, in bergamo, bramante celebrated venice’s supremacy painting an architectural apparatus that illusionistically unifies the smooth surface, consisting of two pre-existing medieval elements, in a single front, which becomes the background of the square (figs. 2 and 3). in this apparatus he inserted monumental figures that evoke moral, philosophical, and cultural messages. the architectura picta, starting from the top, consists of a painted loggia bounded by a balustrade; below, between the front openings, in the architectural sfondato, it shows square-based niches bounded by pillars, with the gigantic figures of the seven sages of greek antiquity: solon, epimenides, pittacus, periander and chilon are the ones identified to date (figs. 3 and 4). the thirteen fragments of the preserved gigantic decoration, discovered on the façade in 1927 and then strappati (i.e. detached), are nowadays placed in the sala delle capriate of palazzo della ragione, museo delle storie (located in the same square, piazza vecchia, as palazzo del podestà). here, the great perspective scenography was rebuilt (fig. 2), according to the concept of “eloquence of architecture”, “considering the edifice as an entity that expresses concepts, that speaks, that communicates” (argan 1984). fig. 2 – the façade of palazzo del podestà on piazza vecchia, in bergamo. photography by jennifer coffani. bramante and his work of painted façades: bergamo and lombardy 17 color culture and science journal vol. 13 (1) doi: 10.23738/ccsj.130102 fig. 3 conference “bramante a bergamo e la città a colori” (2018). reconstruction and video mapping of bramante’s fresco strappi on the current façade of the palace. photography of the projection by alessandro bettonagli. fig. 4 – starting from the top: fragments of the loggia balaustrade, from which a lively polychromy can be noticed. next to it, fragment of an architecture and of the sfondato between the openings, with the bright blue of the sky. next to it, a fragment with an inscription. below, the philosophers chilon and epimenides and, on the right, the fragment of another philosopher. again below: fragment of a figure and fragment of an architecture. cornice with a frieze. fragments. photographs by alessandro bettonagli. bramante and his work of painted façades: bergamo and lombardy 18 color culture and science journal vol. 13 (1) doi: 10.23738/ccsj.130102 a vivid color range, made up by few recurring colors, emerges clearly from these fragments, which are unfortunately incomplete (fig. 4). as a first reference for the analysis, we chose the comparison with the colors of the norma italiana (1991) colorimetria. denominazione dei colori. uni 9810, which defines a chromatic wheel with 24 hues, 5 levels of saturation and 7 levels of brightness. the architectural fictions, with a strong chiaroscuro that emphasizes depth and the sfondati, are in the colors: “giallo aranciato brunastro” and “bruno giallo aranciato” (hue 2 p. 5 – giallo aranciato, i.e. orangey yellow). the loggia balaustrade alternates small columns in a marble color, in “grigio giallo aranciato” shade (hue 2. p. 5) and, one every two, in “rosso forte chiaro” shade (hue 7 p. 10 – rosso, i.e. red), perhaps in reference to the pink marble of verona. the green handrail, in “giallo verdastro forte medio” shade (hue 24 p. 27 giallo verdastro, i.e. greenish yellow), is in stark contrast with them. the two preserved monumental figures of philosophers show robes with rich draperies in bright green, even if in different hues. in the first figure, the green robe in “verde forte chiaro” shade, (hue 22 p. 25 – verde, i.e. green), is accompanied by a red mantle in “aranciato rossastro forte chiaro” shade (hue 5 p. 8 arancione rossastro, i.e. reddish orange) with bright yellow edges in “giallo aranciato forte chiarissimo” shade (hue 2 p. 5 giallo aranciato, i.e. orangey yellow). in the second figure, the large green mantle in the shade “verde ciano moderato scuro” (hue 21 p. 24 verde ciano, i.e. cyan green) opens onto the tunic colored in “arancione forte molto chiaro” (hue 4 p. 7 – arancione, i.e. orange). the lining of the mantle is purple, in the shade “violetto purpureo moderato medio” (hue 13 p. 16 violetto purpureo, i.e. crimson purple). the latter color is present also in the other large fragment of a figure, while blue is found in the fragment with green and red. therefore, we find once again green and red, complementary colors, while green is found almost in all fragments, even if in a small part. the bright blue of the sky that breaks through the wall between the openings is a “ciano bluastro moderato molto chiaro” (hue 18 p. 21 ciano bluastro, i.e. bluish cyan). the drawings of architectures in perspective for the frescoes of casa angelini façade (fig. 5), still in bergamo, were attributed to bramante, too, and dated between 1480-85 (bruschi, 1985). besides these, also the drawings for the interiors, which depict complex architectural perspectives with a typically mantegnesque character, were attributed to him (fig. 5). on the outside, the colors appear in a rich polychromy and more reminiscent of an extremely decorative late-gothic taste, even if within classical references. here too, we find the bright light-blue of sfondati and the relevant presence of very bright red and green colors. fig. 5 – casa angelini interiors, where the projects are preserved. in the basement, the complex painted renaissance architectures with figures. on the right, design for the façade in a lively polychromy, architectural sfondati with figures and wide landscapes. image taken from: brochure of the conference. bramante and his work of painted façades: bergamo and lombardy 19 color culture and science journal vol. 13 (1) doi: 10.23738/ccsj.130102 3. the main fresco façades in milan his main activity took place in milan, at the court of ludovico il moro. here, he still was “ingegnerius et pinctor” (bruschi, 1985) and continued his activity as a painter and perspective expert. his name is mentioned for the first time in a 1481 act about a drawing for the milanese engraver bernardo prevedari. the drawing depicts a temple in ruins, populated with figures. this is considered a real architectural piece, the first that is clearly influenced by his education in urbino and by alberti. in it, the figures show the closeness to ferrarese painting and especially to mantegna (bruschi, 1971). lomazzo attributed to him the figure of the poet ausonius and “other colored figures” in a façade in piazza dei mercanti (lomazzo, 1584). the frescoed decoration of a hall in casa panigarola in milan, located in the rear part of piazza dei mercanti, is attributed to him, and dated to 1480-85 (fig. 6). it constitutes a monumental work, fortunately largely preserved at the pinacoteca di brera. the theme is “men-at-arms”, painted within niches, which articulate the hall in an illusionistic way. this was defined as a “fundamental work of spatial modeling, obtained through the perspectival system that breaks through the walls with semicircular niches, marked by lesenes, in which heroic figures of men-at-arm are inserted, along with the figures of the philosophers heraclitus and democritus, in the entrance overdoors” (bruschi, 1985). these materials in particular allow us to carry out a wider and more significant chromatic and perceptive analysis, thanks to almost completely preserved strappi (i.e. detachments), compared to the fragments of palazzo del podesta in bergamo. as far as colors are concerned, here too there is a recurring range of few fundamental colors, often complementary, declined in different hues, with a good color saturation and a strong chiaroscuro. the colors are green, yellow, red; red is often combined with green, yellow with green and red, alternated in their prevalence. fig. 6 – from the top: man with a mace; man with a broadsword; heraclitus and democritus; man at arms; man with a halberd; man at arms; a cantor. following, details of the previous subjects with the recurrence of colors. photographs by the author. bramante and his work of painted façades: bergamo and lombardy 20 color culture and science journal vol. 13 (1) doi: 10.23738/ccsj.130102 in detail, in the first standing figure we can find three colors: a green mantle “verde giallastro debole chiaro” (tinta 23 p. 26 verde giallastro, i.e. yellowish green) accompanied by dark-yellow breeches and bodice in “giallo aranciato brunastro forte chiaro” (tinta 2 p. 5 giallo aranciato, i.e. orangey yellow) and a red robe in “rosso purpureo moderato chiaro” shade (tinta 8 p. 11 rosso purpureo, i.e. crimson red). the second standing figure presents only two colors: the faux bronze dark yellow of the partial armor, and the red of the mantle in “rosso aranciato forte molto chiaro” shade (tinta 6 p. 9 rosso aranciato, i.e. orangey red). on the other hand, the two philosophers, who are talking to each other, show mantles and draperies in the same hues. the first mantle is red in “rosso purpureo moderato chiaro” shade (hue 8 p. 11 rosso purpureo, i.e. crimson red) and the yellow robe is a “giallo debole chiaro” (hue 1 p. 4 – giallo, i.e. yellow). the other figure’s drapery is in bright yellow “giallo aranciato moderato chiarissimo” (hue 2 p. 5 giallo aranciato, i.e orangey yellow), and white robe. the four partial figures, preserved up to their bust, present the following colors: the first one shows the combination of the bright yellow of the mantle in “giallo aranciato moderato chiarissimo” shade (hue 2 p. 5 giallo aranciato, i.e. orangey yellow), which is the prevailing color, with the light green of the robe, in the same color “verde giallastro debole chiaro” (hue 23 p. 26 verde giallastro, i.e. yellowish green) of the first standing figure. the second figure shows the same combination of a golden-yellow mantle in the shade “giallo aranciato moderato chiarissimo” (hue 2 p. 5 giallo aranciato, i.e. orangey yellow), which is the prevailing color, with the light-green color “verde giallastro debole chiaro” (hue 23 p. 26 verde giallastro, i.e. yellowish green) of the lapels, while the sleeves are in the same red color “rosso purpureo moderato chiaro” (hue 8 p. 11 rosso purpureo, i.e. crimson red) of the first standing figure. the third one still presents the same combination, but with a prevalence of green of the wide bodice in “verde giallastro debole chiaro” (hue 23 p. 26 verde giallastro, i.e. yellowish green) with a pinkish-red decoration in “‘rosso purpureo moderato chiaro” shade (hue 8 p. 11 rosso purpureo, i.e. crimson red), and parts of the armor in a faux bronze dark yellow color. lastly, in the figure of the cantor we still find the same combination of colors, with a prevalence of the green color of the mantle, and then yellow and dark red. all the niches are in monochrome with the architectural order in faux marble color and a light brown background, with the motif of the continuous circle running above the capitals of the pilasters. the painted façade of casa fontana, now silvestri, in milan in corso venezia 10 (fig.7), is probably from this same period, if created by bramante (rosa and reggiori, 1962), (bruschi, 1971), (lomazzo, 1590). this façade is painted in monochrome, in very light umber, using chiaroscuro. it preserves only partially the architectural structure, colored in faux marble, formed by two vertical orders, with semi-columns on the ground floor and lesenes on the upper floor, where are painted the gigantic figures standing in front of the lesenes, or between the specchiature (i.e. wall panels), and classical friezes with tritons, putti and clipei. fig. 7 the façade of casa fontana silvestri in milan, corso venezia. details of the preserved frescoed part. photographs by the author. bramante and his work of painted façades: bergamo and lombardy 21 color culture and science journal vol. 13 (1) doi: 10.23738/ccsj.130102 in pavia, the drawing for palazzo carminali, bottigella (at least the ground floor) in via cavour, is attributed to him. here, the elevations on the courtyard present a lively and classical pictorial decoration, with figures in false niches in the walls and grotesque friezes. in vigevano, between 1492 and 1494, bramante works with leonardo for the great design of the square, where he still uses the fresco decoration for the exteriors of the adjacent edifices of this great urban space. perhaps, the urban plan of the square (realized between 1492 and 1494) could be attributed to him, along with a scheme used for the painted decoration (1494) on the façades bounding it. the decoration shows the insertion of false triumphal arches, placed, as alberti suggests, where the roads give access to the “forum” (bruschi, 1971). on the three sides, the porticoed façades are punctuated by the scanning of the great monochrome painted candelabra, on the sides of the openings of the piano nobile (i.e. the main floor), that give life to a scenic continuous background, that amplifies the space of the small square through repeated motives. these candelabra can also be found in milan, in the church of santa maria delle grazie in the tribune he built, and in the pilasters of the renaissance portal. 4. conclusion as a first reference for the analysis, we chose the comparison with the colors of the norma italiana (1991) colorimetria. denominazione dei colori. uni 9810, which defines a chromatic wheel with 24 hues, 5 levels of saturation and 7 levels of brightness. it should be noted, however, that in the future it is planned to carry out the survey also through the comparison with the munsell system and the munsell book of color, as well as other color charts, for a wider dissemination of data at an international level (falzone, 2014). from the examination of the frescoes of palazzo del podestà in bergamo, and especially of casa panigarola in milan, the identification of the chromatic range confirms the small number of colors, which are recurring, very vivid, and almost always complementary. in bergamo, in the two preserved figures, green and red prevail. the range of colors, according to the color wheel, is represented in table 1. table 1. in milan too the figures show a prevalence of green, yellow and red. the niches are in monochrome, with the architectural order in faux marble color and the background in light brown. the range of colors according to the color wheel is shown in table 2. therefore, in all the figures the prevailing colors are: 1. green, in its different hues and tints (tints from 19 to 23 in the color wheel). 2. yellow (tints from 1 to 2) 3. orange (tints from 3 to 5), 4. red (tints from 6 to 8). hue shades hue 2 p. 5, giallo aranciato (orangey yellow) ‘giallo aranciato brunastro’; ‘bruno giallo aranciato’; ‘giallo aranciato forte chiarissimo’; ‘grigio giallo aranciato’ hue 4 p.7, arancione (orange) ‘arancione forte molto chiaro’. hue 5 p. 8, arancione rossastro (reddish orange) ‘arancione rossastro forte chiaro’. hue 7 p. 10, rosso (red) ‘rosso forte chiaro’. hue 12 p. 15, violetto purpureo (crimson purple) ‘violetto purpureo moderato medio’. hue 18 p. 12, ciano bluastro (bluish cyan) ‘ciano bluastro moderato molto chiaro’ hue 21 p. 24, verde ciano (green cyan) ‘verde ciano moderato scuro’ hue 22 p. 25, verde (green) ‘verde forte chiaro’ hue 24 p. 27, giallo verdastro (greenish yellow) ‘giallo verdastro forte medio’ bramante and his work of painted façades: bergamo and lombardy 22 color culture and science journal vol. 13 (1) doi: 10.23738/ccsj.130102 table 2. followed by purple (tints from 11 to 13), lightblue (tints 18 and 19), and blue (tints 16 and 17). the similarities with the color range of works by coeval or immediately previous authors are emphasized: paolo uccello especially for the dark greens and reds, melozzo for the bright greens and light-blues and the dark crimson-red that we also find in piero della francesca. mantegna for the “rosso aranciato moderato molto chiaro” (i.e. “very light moderate orangey red”), the golden yellow, and green. all are authors who show a wide use of complementary colors. 5. conflict of interests the author declares that she has no conflicts of interest. 6. founding source declaration the author received no specific funding for this work. 7. acknowledgment my heartfelt thanks for the collaboration to the ministry of culture of the municipality of bergamo and in particular to dr. arianna bertone, collaborator at the ministry, and ms. carla gandolfi, secretary. i would also like to thank the museo delle storie di bergamo and in particular dr. jennifer coffani, in charge of the photographic archive. i also thank mr. alessandro bettonagli, author of the 2018 photograps of the fresco strappi, preserved in sala delle capriate in palazzo della ragione, bergamo. 8. short biography of the author patrizia falzone • former full professor of architectural survey, dad department, scuola politecnica, university of genova. she has carried out study and survey activities in the field of historical architecture and in the field of study and survey (materials, colors, decorative elements) of exterior surfaces of built architecture, aimed at their knowledge for enhancement, conservation and redevelopment of buildings and spaces of the historic city. references alberti, l.b. (1950) della pittura. (mallè l. ed.). firenze: g.c. sansoni. (original work published in 1436) argan, g.c. (1984) introduzione ai lavori del convegno. in terminiello, g. r., simonetti, f. (eds.) facciate dipinte: conservazione e restauro: atti del convegno di studi, genova, 15-17 aprile 1982. genova: sagep. p. 10. isbn: 978-8870581010 averlino, a. il filarete (1972), trattato di architettura, (finoli, a. m., grassi l. eds.). milano: il polifilo. (original work published in 1460) beltrami, l. (1901) bramante a milano: (documenti e disegni inediti), rassegna d'arte, i, 33-37. bruschi, a. (1971) bramante, donato. in dizionario biografico degli italiani. xiii, [borremans-brancazolo]. roma: istituto della enciclopedia italiana. bruschi, a. (1973). bramante. london: thames & hudson ltd. bruschi, a. (1985). bramante (pp. 27, 28, 37, 53, 56, 74). roma; bari: laterza. falzone, p. 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(original work published in 1568) 79 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140110 the relationship between photo retouching and color grading ivan magrin-chagnolleau 1, 2 1 aix marseille univ, cnrs, prism, marseille, france 2 chapman university, orange, california corresponding author: ivan magrin-chagnolleau (ivan.magrin-chagnolleau@cnrs.fr) abstract this paper deals with photo retouching and color grading. it proposes a simplified workflow for both of them. it also points the commonalities and the differences, and further explore the relationship between the two, including a phenomenological point of view as well as an aesthetic point of view. it also discusses the implications of that relationship in pedagogy. keywords photography retouching workflow, color grading workflow, color aesthetics, phenomenology of the creative process, pedagogy. received 09/11/2021; revised 27/12/2021; accepted 19/01/2022 the relationship between photo retouching and color grading 80 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140110 1. introduction the aim of this paper is to explore the relationship between photo retouching and color grading. the idea of this paper came to life when i started to reflect on my practice as both a photo retoucher and a color grader, and trying to understand if i approached both in the same way, or if i had different modus operandi for each of them. i am particularly interested in two aspects: (i) why do we make the decisions we make in a creative process, here in retouching a photo or in grading a film, and (ii) what are the aesthetic implications of this relationship between photo retouching and color grading. i am speaking from the point of view of a scholar dedicated to photography and film philosophy and aesthetics, but also from the point of view of a long-term practitioner as both a photo retoucher and a color grader. the work presented here is therefore the result of a constant dialog between practice and theory. there are many publications about the aesthetics of photography (see for instance costello, 2018) and the aesthetics of film (my favorites are alekan, 2001, and storaro, 2011; see also for instance jarvie, 2015). there are a few publications about photo retouching (most of them are mostly guides about how to use the softwares) and color grading (see for instance the excellent haine, 2019), but they are mostly technical. and this is mostly through online tutorials that ones learns to use photo retouching or color grading softwares. there are very few publications specifically about the aesthetics of photo retouching and the aesthetics of color grading, and these topics are sometimes vaguely touched upon in books about photography aesthetics and film aesthetics, or in books about photo retouching and color grading. but in my knowledge, no one has ever explored the relationship between the two. the main aim of this paper is to touch upon this relationship. as far as color is concerned, there are a few excellent books about the theory of color (see for instance mollica, 2012, or bleicher, 2012). the outline of the paper is as follows: the first part deals with photo retouching, and tries to answer the question of why we do it in the first place. then, a simplified workflow for photo retouching is proposed, and a discussion about aesthetic considerations follows. a second part then deals with color grading, and proposes a simplified workflow for it, as well as a discussion about aesthetic considerations concerning it. a third part compares the two approaches, points the commonalities as well as the differences, and also shows how the two approaches can feed each other. and finally a conclusion wraps-up the paper. 2. photography retouching and color most professional photographers nowadays use softwares from the adobe suite. one particular program, lightroom, has been developed with the photographer workflow in mind, and offers various ways to save a lot of time in the process. even though the topic i discuss here is not related to the use of a particular software, part of how i do things might be. there are also numerous plug-ins that exist today, whose job is to allow a professional photographer to save time. i am very fond of color efex pro (and silver efex pro for black&white photography) [1]. 2.1. why do we retouch a photograph let us first go back to the time before the digital revolution. you did not have that many options to control the final look of an image. you had to carefully think at the moment of taking it (see for instance the visualization technique developped by ansel adams in adams, 1995). and then, the rest of it was a matter of how you developed your film, and then how you printed the chosen picture. this was all chemical, and particularly for color photography, you would generally rely on a strong collaboration with a lab. occasionally, some photographers would do their own developing and printing jobs, particularly in black&white photography, but that was not the norm. today, retouching a photo is something a photographer can do on their own much more easily. all they need is to open the raw digital file inside a software, and then push buttons and see the corresponding result. this process is non-destructive. it has become entirely part of the creative process. because there are so many possibilities now, you end up playing with the possibilities and expanding your horizons. so why do we retouch a photograph? we do it to improve the look of the photograph, in terms of contrast, colors, framing, final look, etc. but we also do it to try new things, to play with the possibilities of the tools we use. photo retouching is therefore an investigative process. 2.2. what is the color component of photo retouching in this whole process, not everything is directly related to color, though most of it has an impact on how color is perceived. for instance, changing the exposure of a picture impacts the perception of color saturation: making a picture darker tends to make us perceive it as more saturated. the first steps of a retouching workflow often deals with brightness and contrast. and then we start playing with color. we can do several things at this point. we can check the setting of the white balance, and if we are using raw the relationship between photo retouching and color grading 81 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140110 files, we can choose a different white balance even after the picture has been taken. we can also tell the software where our real whites are and let the software change the settings accordingly. this whole process, called “removing a color cast”, consists in compensating for some technical limitations of the camera we used, or the circumstances of the picture. there is then the possibility of wanting our picture to look a bit different colorwise. for instance, if you took the picture of a sunset, and you noticed that your camera tended to bring the whole scene a bit more towards yellow than pink or orange, you can then add a tint of pink or orange to make the picture look closer to what you remember or what you intended. 2.3. a possible workflow for photography retouching let me now propose a simplified workflow for photo retouching. first of all, as mentioned earlier, i mostly use lightroom to do my work on pictures. with lightroom, you can import images, sort them, define all sorts of metadata, retouch them, and then export them. i will deal here only with the part of the workflow that deals with retouching pictures. i also want to point out a very important principle in art making. there are no immuable laws. even when you have a workflow in place, occasionally you will choose to deviate from it. besides, this workflow is also meant to be rethought, and hopefully improved with time. photo retouching simplified workflow: • test the auto setting: it consists in using a button that provides automatic settings for the given picture, based on some values that the software extracts from the image. sometimes, the resulting retouching is close enough and i continue from there, and sometimes the original picture is closer to what i want and i then start with the original picture. • adjust the exposure: it is possible at this stage to modify the white balance inside the software, but i rarely do it. it is because i have usually set the white balance up before taking the picture, and therefore rarely need to change it later. but this is a possibility that is worth mentioning. personally, i often tend to lower the exposure a bit. i have found that, most of the time, the auto button tends to set an exposure that is a bit too bright for my taste. but occasionally, i will do the opposite, increase the exposure slightly. there are no rules. it is mostly a matter of experience and taste. • adjust the contrast: i tend to prefer more contrasted pictures, because that makes them more pictural, more graphical, which is usually closer to my personal taste in term of images. for those first steps, auto, exposure, and contrast, i usually use my eyes only. then, i rely mostly on the histogram, which is a diagram showing the repartition of the values of all the pixels of an image from black to white, and a bit on my eyes. • adjust the highlights and the shadows: the idea behind those two steps is to occupy the whole range of brightness from black to white, in order to have the best possible distribution of pixels. this is not always the best option, but more often than not, it brings the image closer to a pleasing image. • adjust the texture, the clarity, the dehazing, and the sharpening: these four sliders have to do with the granularity of the picture, and how it looks in terms of details. i barely change them, but often just a bit, to increase the crispiness of the picture. • adjust the vibrancy and the saturation: we finally get to the color aspect of retouching pictures. i usually utilize two sliders to do it, the vibrancy slider and the saturation slider. in most cases, i increase both a bit and that gives me a richness in terms of color that i like. occasionally, i will desaturate slightly, but only for very particular photos. • use the color efex pro plug-in: i will then open the picture in color efex pro, and will play with some of the possibilities of this plug-in to enhance the picture. it is important to notice that part of the settings that i use prior to opening the color efex pro plug-in are decided with the use of the plug-in in mind. from experience, i know how to prepare an image before running the plug-in. if i was not planning on using the plug-in at all, i would make different choices. once in the plug-in, i have many options. some of them have to do with some creative techniques effecting contrast, other effecting color, and so on. some of the looks are also mimicking some vintage looks. 2.4. aesthetics considerations for photography retouching i often wonder why i make the choices i make, or why photographers in general make the choices they make, in particular regarding color. one way to answer that question is by saying that a photographer remembers the scene he took a picture of, and consciously or subconsciously tries to match the picture and the memory of that scene. a perfect example of that is when taking a picture of a sunset. the captured picture will always deviate from what was really in front of our eyes. and the temptation would be to correct the picture later, to make it as close as possible to what we remember. the relationship between photo retouching and color grading 82 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140110 but that would be forgetting that a picture is only a representation of reality. the truth is much more complex. when i retouch a picture colorwise, i try find the color treatment that would serve that particular picture best, that would enhance the power of evocation of that picture. concretely, there is a part of habit in the process. we tend to do things the way we are used to doing them. but how did we come up with this way of doing? this process is usually incremental. we first learn to do it through practice, on the one hand, and from learning, on the other hand. we can learn from someone, from a book, from an online course or tutorial. all these activities build up our artistic sensitivity, which is also ever evolving. then, once we have a basic workflow, we keep experimenting, and we keep learning from courses, books, tutorials. that process will constantly open perspectives, suggest other ways to do it, sometimes better ways, sometimes not. but as we gain knowledge about the process, be it in practice or by learning, we expand our horizons and the possibilities. at the same time, we develop a way to adapt to a particular photo our own way of doing things, our own style. maybe we try to match aesthetics we love, from photographers we admire. maybe we are also trying to match other media, like painting or film. in the end, there is something subtle guiding us in this quest for beauty, for the most aesthetically satisfying picture. it has to do with what motivated us to take the picture in the first place, what we want to express through that picture, something that has to do with some universal truth, but seen through the prism of our own experience and our own peculiarities. figure 1 is an example of a photograph before retouching (left) and after retouching (right). fig. 1. the image on the left is the raw picture, as taken with the camera. the image on the right is a possible version of the picture after retouching it.this picture is part of the series "calanques". 3. color grading and color let us move on to color grading. i got involved in it quite naturally. because i had done a lot of photo retouching. because i was making films. and because it made sense to me to do my own color grading on my film projects. and then i started doing it for other people. 3.1. why do we grade films there is a slightly different reason why we grade films, compared to photo retouching. in color grading, there is an important motivation which is to save shots. there are situations when the images recorded by the cinematographer present some technical problems (low light, important color cast, etc.). one of the goals of color grading is then to save the shot, that is, to bring it to a place where it can be used in the film without disrupting the flow of the storytelling. the rest of the job pretty much resembles that of a photo retoucher, with one big difference: we are now working on moving images, that is, we are not just retouching one still the relationship between photo retouching and color grading 83 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140110 image, or a series of a few images, but 24 or 25 or 30 images per seconds, from the beginning of a clip to the end of a clip, clip after clip, from the beginning of the film to the end of the film. this work is comparatively huge in terms of involvement and time, and there are also considerations about the unity of a shot, of a sequence, of a film. 3.2. what is the color component of color grading as with photo retouching, the whole process of color grading does not have to do with color, although it can be argued that everything a color grader does impact color perception. but there are mostly two operations that directly have to do with color. the first one consists in removing a color cast, that is, identifying what is supposed to be white and trying to bring those particular pixels back to white. it can also be done by using some particular scopes, called parade, which display the repartition of luminosity for each of the three sensors (red, green blue), and often allows to detect discrepancies between them, thus indicating a possible color cast. the second one concerns finding the look of a clip, a sequence, or an entire film. this often includes considerations on whether the mood of that particular clip, sequence, or film should be colder or warmer. 3.3. a possible workflow for color grading let me now propose a simplified workflow for color grading. the software i am using is davinci resolve, which has imposed itself as the professional tool for color grading. it was first developed only as a color grading tool. now, davinci resolve is an entire post-production suite. the workflow i propose here is not specific to davinci resolve though. also, as i stated previously for photo retouching, a workflow is a guideline. but there is no law preventing to occasionally deviate from that workflow. and a workflow is also here to be continuously improved. color grading simplified workflow: • brightness / contrast / highlights / shadows: for color grading, i prefer using curves, which is a tool i rarely use for photo retouching. the reason why i like curves in color grading is that it allows me to do several operations all at once, while using at the same time my eyes and the scopes. with some experience, it takes only a few seconds to correct the brightness / contrast / highlights / shadows of a clip all at once. to use the curves tool, i usually set up a point close to white and then move it until i get the expected result. and then i set a point close to black and do the same thing. • removing a color cast: i use again the curves tool to do it, but this time, i use it color by color (red, green, blue). i will mostly use the scopes as a guideline, but i also keep an eye on the image itself. • secondary correction: the first two steps are called primary correction, meaning they are applied to the whole image. a secondary correction is a correction that is only applied to a part of the image, for instance a face. it requires the use of a mask, and then tracking of the mask across the whole clip. this is used only when necessary as it is very time consuming to set it up and adjust it. this is due to the fact that you often have to check the mask frame by frame, and adjust it when it deviates from where it is suppposed to be set up, which often happens when the object that is tracked, for instance a face, is moving fast in the shot. it is often used to lighten or darken an area of an image, to make it more or less present. it is also used to adjust a color, for instance a skin color. • adjusting between clips and sequences: this step consists in adjusting consecutive clips and/or sequences in order to smoothen the experience of the viewer. sometimes, the opposite effect is sought after: increase the transition effect between one clip and another, or between one sequence and another. • working on the look of a clip / sequence / film: the last step consists in working on the look of a clip, sequence, or film. this usually requires applying some additional effects on the images, often through the use of luts (lookup tables) which are preset tables allowing to apply entire looks and/or filters to clips. color is often an important component of the look of a film. this is mostly due to the correlation between color and mood. the last two steps can be inverted. it is sometimes possible to start working on looks before doing all the clips or sequences matching. 3.4. aesthetics considerations for color grading again, the question that comes to mind is: why do we, as color graders, make the choices we make? the answer here is not much different from the one i gave for photo retouching. habit is part of it, improving a process too, and matching a particular aesthetic we like. but there is a big difference here. photography is usually a one-person medium. film is a collaborative medium and the color grader is not the only person making decisions on the color grading process. the director is also involved, quite often too the director of photography, and sometimes other people too (some producers, some studio executives). it makes the process more complex, and requires the color grader to be able to argue their choices, the relationship between photo retouching and color grading 84 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140110 and also to be flexible enough to integrate the vision of other people, even when that vision contradicts their own. figure 2 is an example of a frame before color grading (left) and after color grading (right). fig. 2. the image on the left is the frame as it was captured by the camera. the image on the right is the frame after it has been color corrected. this frame was extracted from the music video "emmanuelle". 4. a dialog between photography retouching and color grading let us now investigate on the relationship between photo retouching and color grading. this is rarely done because it is not so common to find people who do both. i happen to do both, and i have consistently and often written accounts of my work as both. this led me to think that a good color grader has to be a good photo retoucher (the opposite is not necessarily needed). it is due to the fact that the building blocks of working on the look of a film is to work on the look of images. writing consistently on my work as both a photo retoucher and a color grader also led me to see a dialog between the two, pointing the similarities as well as the differences, and developing an understanding about the tight relationship between the two, and how they could mutually influence each other. this, of course, also has important implications from a pedagogical point of view. 4.1. similarities between photography retouching and color grading as you probably noticed, there are similarities in the workflows i presented for photo retouching and color grading. in both cases, we deal with the same first three steps: correcting brightness and contrast, correcting color, and applying a look. another similarity has to do with the kinds of tools we find in the softwares that we use to do these jobs. even though color grading has a few additional tools, the tools we use for the first three steps are very similar. there are sliders, curves, and scopes (mostly a histogram for photo retouching). finally, aesthetic considerations about what makes an image beautiful and/or meaningful and/or impactful are also very similar. 4.2. differences between photography retouching and color grading let us now investigate about the major differences between the two. the first major difference has to do with the nature of the medium. because a film is a rapid succession of still images, there are important additional considerations to take into account when color grading. first, at the very basic level, we color grade a clip and not a still image. it means we have to select the referent image carefully, if we want the correction to translate in a satisfying way to the other frames of the clip. it also requires to test the correction we made on the referent image across the whole clip, by watching it entirely to see if there is anything else to adjust. this is particularly difficult when the nature of the material is changing drastically across the clip, as is the case for a long sequence shot. in that particular case, it is often possible to have dynamic settings of some color grading parameters, that is, to have some parameters that can vary during the shot according to what happens in the shot. we also mentioned earlier what is called a secondary correction. of course, it is not uncommon to correct only part of a photograph when we retouch it. but with film, we are also concerned with tracking, that is, with the fact that this secondary correction has to be applied along a clip and not just to a still image, and to the right area of the image, frame after frame. the relationship between photo retouching and color grading 85 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140110 there is also the question of clips matching, which does not exist in photo retouching, except when we work with serial photography. when matching clips, it is not just the aesthetics of a still image that we are after, but also the aesthetics of an entire sequence. and that requires different analytical skills and aesthetic knowledge. this is equally true when matching the sequences of a film to give its visual unity to a film. 4.3. the relationship between photography retouching and color grading i would like to expand the previous discussion about similarities and differences between photo retouching and color grading by exploring the relationship between the two a bit further. because the nature of the medium is not the same (still images versus moving images) and because the nature of the work is different (solitary work versus collaborative work), it is not uncommon to make some discoveries in one medium and then translating that discovery (when possible) to the other one. some of my work as a photo retoucher has deeply influenced some of my work as a color grader, and vice versa. because the workflow is not entirely the same, and because the tools are not entirely the same, discoveries concerning aesthetics and also the use of tools and the workflow can happen indifferently in one medium or the other. this is also why a photographer can be influenced by a filmmaker and a filmmaker can be influenced by a photographer. but this relationship goes much deeper. and this is something that is harder to explain since it is mostly phenomenological, that is, based on a lived experience [2]. it is a bit as if those two things were only one thing for me and, as i work on a photo, i mobilize knowledge from both the photo and the film worlds, and from both my experiences as a photo retoucher and a color grader. it is the same when i work on a film as a color grader. this is also the reason why i keep learning about photography to feed my film work, and why i keep learning about film to feed my photo work. 4.4. pedagogical implications of the relationship between photography retouching and color grading there are important implications of that relationship between photo retouching and color grading in the area of pedagogy. i always have students of color grading work on photo retouching first, and i encourage them to keep doing so all over their career. first, because the problem of photo retouching is a simpler one than the problem of color grading, and a building block for it. but also because the questions you ask yourself as a photo retoucher, consciously or unconsciously, can inform to great lengths the questions you ask yourself as a color grader. i also suggest to students of photography who are particularly interested and fluent in photo retouching to look into color grading as a career, or at least as a strong interest of theirs. this is due to the fact that working as a color grader can inform back on your process as a photo retoucher, and make you a better photo retoucher. in those two cases, i am not only talking about the tools, and how you can discover various uses of them when going back and forth between photo retouching and color grading. i am also speaking about aesthetics, and the various parameters and aspects that contribute to all the decisions we make while photo retouching or color grading. those operations are very complex, and it takes a lot of times to refine the artistry. any input that can help refine it is always welcome. and working in photo retouching can definitely help refine the artistry of color grading. and the same is true the other way around. 5. conclusion in this paper, i have dealt with photo retouching and color grading. i have questioned why we were doing it in the first place. i have then offered a simplified workflow for both. i have also discussed the commonalities and the differences between the two, exploring the tight relationship they had with each other. i have also explored some implications of that relationship in pedagogy. the next steps of this research would be to expand even further on the relationship between the two, as well as to develop further the implications for practice and pedagogy. in particular, it could be really interested to give some more detailed accounts of a phenomenology of photo retouching and color grading, and see where the creative processes in both activities intersect and diverge. 6. conflict of interest declaration the author declares that nothing affected their objectivity or independence and original work. therefore, no conflict of interest exists. 7. funding source declaration this research did not receive any specific grant from funding agencies in the public, commercial, or not-forprofit sectors. the relationship between photo retouching and color grading 86 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140110 8. short biography of the author ivan magrin-chagnolleau is an artist philosopher who has been involved in art making as well as academic research and teaching for most of his life. he is affiliated with the cnrs in france, and currently works with the prism laboratory in marseille, a joint-lab between cnrs and aix-marseille university investigating on the relationships between art and science. he is also affiliated with chapman university in california. his interests include: the creative process and its phenomenological dimension, art and philosophy, aesthetics, artificial intelligence and creativity, art and spirituality. notes [1] i owe the discovery of that plug-in to rick sammon (2016). [2] for the readers who are insterested in learning more about phenomenology, you can read for instance husserl, 1985, husserl, 1992, or merleau-ponty, 1976. references adams, a., & baker, r. (1995). the camera (reprint edition). ansel adams. alekan, h. (2001) des lumières et des ombres. paris: éditions du collectionneur. berleant, a. (2004). re-thinking aesthetics: rogue essays on aesthetics and the arts. new york: routledge. bleicher, s. (2012). contemporary color: theory and use (2nd edition). clifton park: delmar, cengage learning. brown, b. (2016) cinematography theory and practice, third edition. new york: focal press. brown, s., street, s., & watkins, l. (eds.). (2012). color and the moving image: history, theory, aesthetics, archive. new york: routledge. costello, d. (2018). on photography: a philosophical inquiry. new york: routledge. fissoun, d. (2020). color correction with davinci resolve 16. blackmagic design learning series. frost, j. b. (2009) cinematography for directors: a guide for creative collaboration. studio city: michael wiese productions. haine, c. (2019) color grading 101. new york: routledge. hullfish, s. (2012the art and technique of digital color correction, 2nd edition. new york: routledge. hurkman, a. v. (2013). color correction handbook: professional techniques for video and cinema (2nd edition). peachpit press. hurkman, a. v. (2013). color correction look book: creative grading techniques for film and video. peachpit press. husserl, e. (1985). idées directrices pour une phénoménologie. paris: gallimard. husserl, e. (1992). l’idée de la phénoménologie. paris: puf. hyman, j. (2006) the objective eye: color, form, and reality in the theory of art. chicago: university of chicago press. jarvie, i. (2015). philosophy of the film: epistemology, ontology, aesthetics. new york: routledge. magrin-chagnolleau, i. (2013) 'the use of color in theatre and film', in proceedings of aic 2013, pp. 1481-1484. merleau-ponty, m. (1976). phénoménologie de la perception. paris: gallimard. mollica, p. (2012) color theory. mission viejo: walter foster. rabiger, m., & hurbis-cherrier, m. (2020). directing: film techniques and aesthetics. new york: routledge. sammon, r. (2016) evolution of an image. new york: routledge. storaro, v. (2011) writing with light, colors, and the elements. florence: mondadori electa. cultura e scienza del colore color culture and science 103 cultura e scienza del colore color culture and science | 10 | 2018 issn 2384-9568 1maria martone maria.martone@uniroma1.it [corresponding author] 2floriana papa floriana.papa@uniroma1.it 1department of history, drawing and restoration of architecture, university sapienza of rome 2 phd in science of representation and survey, sapienza university of rome colors, lights and shapes in the naples underground. the “art stations” of line 1 abstract in the integrated subway system of naples, line 1 represents a completely new infrastructural operation. winner of many international awards, line 1 is strongly characterized by so-called “art stations”, designed and then realized not only as an element of transit towards the external city, but as a place for a process of relationship with the surrounding urban fabric. next to a brief description of the places, the paper aims to analyze and document in harmonious way colors, shapes and lights of some of the main stations that have made neapolitan underground a unicum of urban mobility on iron. a sort of color-shape sampling was performed to highlight similarities and differences in color and formal choices. from this sampling we created a palette that collects the main colors in the neapolitan underground. chromatic contrasts and bright and symbolic colors escort the traveler in the neapolitan subway, making these places of peculiar mobility thanks to the work of prestigious architects and contemporary artists. keywords underground colors, art stations, line 1 of naples subway citation: martone m. and papa f., (2018) ‘colors, lights and shapes in the naples underground. the “art stations” of line 1’, cultura e scienza del colore color culture and science journal, 10, pp. 103-118, doi: 10.23738/ccsj.i102018.12 received 02 march 2018; revised 28 june 2018; accepted 09 july 2018 maria martone. architect, researcher she is an aggregate professor in drawing at the department of history, design and restoration of architecture, sapienza university of rome. she carries out her research activity on topics about representation and documentation of architecture, city and territory. her contributions are in collective and monographic publications, in specialized magazines and in conference proceedings and seminars. floriana papa. architect, phd in science of representation and survey at the department of history, design and restoration of architecture, sapienza university of rome, with thesis entitled: “the railway system as a cultural heritage. the case of latina station, in past littoria. from the spoon to the city (?)”. she carries out research mainly on topics abot computer modeling and virtual representation of architecture. italian translation provided: colori, luci e forme nell’underground napoletano. le “stazioni dell’arte” della linea 1 104 cultura e scienza del colore color culture and science | 10 | 2018 | 103 118 martone m. and papa f. issn 2384-9568 doi: 10.23738/ccsj.i92018.12 1. introduction in the underground of naples there is a metropolitan network, not yet completed at all, that crosses the urban territory, unifying the center and the suburb, the plain and the hill, intercepting spaces and places with different nature and history. inside the integrated subway system, line 1 represents a completely new infrastructural operation. originally called “hilly” because the first part connected the vomero’s hill with the city center, the line, from the northern suburbs of naples, reaches today the vomero and the historical center to get the central station, and from there the connection with capodichino airport must start. along its path interchange nodes have been created that allow the connection with other public transport services. line 1 of the naples subway, which is the subject of numerous international awards, is strongly characterized by so-called “art stations”. except the first stations in the seventies eighties of the twentieth century, where the engineering and functional aspects prevailed in the projects, the following stations were designed and then generated not only as an element towards the external city, but as a place where there is a process of relationship with the surrounding urban fabric. this has helped to make the stations object of architectural and artistic design in which many prestigious names of the national and international architectural cultural scene have been tested, coordinated by achille bonito oliva [1]. no more repetitive spaces in each station, but different combinations of colors, lights and shapes that diversify the places and guide the traveler in an unusual “underground” characterized by great spectacular and evocative scenery. the colors of architecture, flooring, cladding, sculptures and art works have a decisive role in shaping an expressive space with a uniqueness character, becoming attractive poles in the urban context. this is the case, for example, of the university station where karim rashid chooses contrasting colors such as pink and lime for the wall and floor coverings to to facilitate the movement of travelers in the two opposite directions of the subway; in addition, the anglo-egyptian artist proposes analogous color combinations consisting of adjacent colors that create particular harmonious effects. they are more and more intense as the traveler reaches the quay. colors-symbol are, however, proposed in the toledo station by tusquet blanca to represent the journey of the traveler from the earth to the depths of the sea and vice versa. the black of the earth, the yellow of the tuff and the blue of the sea presented in different orders of saturation 1. introduzione nel sottosuolo di napoli si configura una rete metropolitana, non ancora completamente ultimata, che attraversa il territorio urbano, unificando centro e periferia, pianura e collina, intercettando spazi e luoghi di diversa natura e storia. all’interno del sistema integrato della metropolitana regionale, la linea 1 rappresenta un intervento infrastrutturale completamente nuovo. denominata in origine “collinare”, in quanto il primo tratto realizzato collegava la collina del vomero con il centro della città, la linea dalla periferia a nord di napoli raggiunge oggi il vomero e il centro storico per arrivare, infine, alla stazione centrale, da cui dovrà partire il collegamento con l’aeroporto di capodichino. lungo il suo percorso sono stati realizzati nodi di interscambio che consentono il collegamento con altri servizi di trasporto pubblico. la linea 1 della metropolitana di napoli, oggetto di numerosi riconoscimenti internazionali, si caratterizza fortemente per la realizzazione delle cosiddette “stazioni dell’arte”. fatta eccezione per le prime stazioni realizzate negli anni settanta – ottanta del novecento, in cui nei progetti ha prevalso l’aspetto ingegneristico e funzionale, le stazioni successive sono state progettate e poi realizzate non solo come elemento di transito verso la città esterna, ma come luogo in cui si compie un processo di relazione con il tessuto urbano circostante. ciò ha contribuito a far diventare le stazioni oggetto di progettazione architettonica e artistica in cui si sono cimentati molti nomi prestigiosi del panorama culturale architettonico nazionale e internazionale coordinati da achille bonito oliva [1]. non più spazi ripetitivi in ogni stazione, ma differenti combinazioni di colori, luci e forme che diversificano i luoghi e guidano il viaggiatore in un “underground” insolito caratterizzato da grande spettacolarità e scenari suggestivi. sono i colori delle architetture, delle pavimentazioni, dei rivestimenti, delle sculture e delle opere d’arte che partecipano in maniera determinante a configurare uno spazio espressivo con carattere di univocità divenendo poli attrattivi nel contesto urbano. è il caso, ad esempio della stazione dell’università in cui karim rashid sceglie per i rivestimenti parietali e pavimentali colori contrastanti come il fucsia e il giallo-verde per favorire la circolazione dei viaggiatori nelle due direzioni opposte di percorrenza della metro; inoltre degli stessi colori l’artista anglo-egiziano propone combinazioni analoghe costituite da colori adiacenti che creano particolari effetti armonici sempre più intensi man mano che si raggiunge la banchina. colori-simbolo sono, invece, proposti nella stazione di toledo da tusquet blanca per rappresentare il percorso del viaggiatore dalla 105 cultura e scienza del colore color culture and science | 10 | 2018 | 103 118 colors, lights and shapes in the naples underground. the “art stations” of line 1 issn 2384-9568 each offer a spectacular gradual monochromatic effect. in garibaldi station, instead, the technique and the play of transparencies and reflections prevail. here the colored mirror paintings by michelangelo pistoletto are inserted. next to a brief description of the places, the paper aims to analyze and document in harmonious way colors, shapes and lights of some of the main stations that have made neapolitan underground a unicum of urban mobility on iron [2]. a sort of color-shape sampling was performed to highlight similarities and differences in color and formal choices. from this sampling we created a palette that collects the main colors in the neapolitan underground. 2. brilliant black and reflecting surfaces in the garibaldi station the shiny material of the black coating used in garibaldi station’s platform, designed by dominique perrault, at a depth of about forty meters, welcomes the passenger in an environment that transmits an unexpected brightness [3]. the feeling of darkness accentuated with the choice of black and the sense of oppression that can be usually felt in underground paths are deleted by the brightness of the wall covering of the gallery consisting of tiles that break up into different levels, differently inclined for the chamfering edges. furthermore, the movement of train and passengers, reflecting itself on the surface of the cladding, which follows the curved profile of the gallery, creates subtle games of reflections, making austere the surrounding environment but at the same time full of hidden energy. two long mirror paintings made of polished stainless steel panels by michelangelo pistoletto, cover the entire length of the first mezzanine in both directions. on these panel colored figures of “virtual passengers” in park and in motion are represented and they join the reflected and real figures of travelers on their way toward the docks or escalators. the internal space of the station is characterized by the presence of metallic and glossy covering surfaces where the real colors of the moving passengers are reflected [4]. a single color stands out: the orange of some protection elements of the escalators that, divided into three crossed pairs, mark the connection with the pedestrian square under the street level of piazza garibaldi. outside large satinated steel pillars, with an inverted pyramid hape, hold up a reticulated “crown”, which covers the large hypogean pedestrian square around which a commercial gallery is developed (figure 1) (amirante, 2011) terra alla profondità del mare e viceversa. il nero della terra, il giallo del tufo e della pietra e l’azzurro del mare presentati in diversi ordini di saturazione offrono ciascuno uno spettacolare effetto monocromatico graduale. nella stazione di garibaldi prevale, invece, la tecnica e il gioco di trasparenze e di riflessi, in cui si inseriscono i colorati quadri specchianti di michelangelo pistoletto. accanto ad una breve descrizione dei luoghi, il contributo si propone di analizzare e documentare in maniera omogenea colori, forme e luci di alcune delle principali stazioni dell’arte che hanno fatto dell’undergroud napoletano un unicum della mobilità urbana su ferro [2]. per evidenziare analogie e differenze nelle scelte cromatiche e formali è stata eseguita una sorta di campionatura di forme-colore da cui è stata tratta una palette che raccoglie i principali colori presenti nel sottosuolo napoletano. 2. nero brillante e superfici riflettenti nella stazione garibaldi il materiale lucido del rivestimento di colore nero brillante della galleria dei binari della stazione garibaldi, progettata da dominique perrault a circa quaranta metri di profondità, accoglie il passeggero in un ambiente che trasmette una luminosità inaspettata [3]. la sensazione del buio accentuata con la scelta del nero e il senso di oppressione che in genere può essere avvertito nei percorsi sotterranei delle metropolitane vengono annullati dalla lucentezza del rivestimento parietale della galleria costituito da mattonelle che si scompongono in più piani diversamente inclinati per la smussatura ai bordi. inoltre, il movimento del treno e dei passeggeri riflettendosi sulla superficie di rivestimento, che segue il profilo curvo della galleria, crea sottili giochi di riflessioni rendendo l’ambiente circostante austero ma allo stesso tempo carico di un’energia nascosta. due lunghi quadri specchianti realizzati su pannelli di acciaio inox lucido da michelangelo pistoletto, coprono la lunghezza di tutto il primo mezzanino in entrambi i versi di percorrenza, in cui sono rappresentate a grandezza naturale colorate figure di “passeggeri virtuali” in sosta e in movimento che si uniscono alle figure riflesse e reali dei viaggiatori in cammino verso le banchine o le scale mobili. lo spazio interno della stazione è caratterizzato dalla presenza di superfici di rivestimento metalliche e lucide in cui si riflettono i colori reali dei passeggeri in movimento [4] . un solo colore si distingue: l’arancione di alcuni elementi di protezione delle scale mobili che, suddivise in tre coppie incrociate, segnano il collegamento con la piazza pedonale sottoposta al livello stradale di piazza garibaldi. all’esterno, grossi pilastri compositi d’acciaio satinato, a piramide 106 cultura e scienza del colore color culture and science | 10 | 2018 | 103 118 martone m. and papa f. issn 2384-9568 doi: 10.23738/ccsj.i92018.12 3. fluorescent colors and fluctuating shapes of karim rashid in the università station the underground rooms of the università station, designed by karim rashid’s new york studio, present strong and bright colors in contrast with the gray tones of the lava stone used for the external arrangement of street furniture and flooring by mendini studio (d’amato, 2011). to encourage the circulation and orientation of travelers, contrasting colors are used, such as pik and lime, already used in the entrances to the station from piazza bovio, where a word in the computer dictionary is printed on each rectangular white ceramic tile, pink towards piscinola and lime towards garibaldi (figure 2). an imposing brushed steel sculpture, which remind the synapses of our brain, and black gloss columns shaped with the head profile, metaphor of the human mind, dominate the large atrium, where the travel enter after passing the entrance stairs. colorful three-dimensional figures, suspended in the white space of a long light box, create the background of the scene, making it even more spectacular. unions of spheres, tubular crosses, multiform and curvilinear solids, that overlap with flat geometric shapes, offer color complementary combinations: green-red, violetyellow, orange-blue; these are unsaturated colors, not bright colors whose brightness is magnified by the white background of the panel. a particular lighting creates a drawing similar to triangular mesh that delimits steel panels that reflect themeself on the synapsi and on a glossy black floor, where a mesh is shown with green, yellow and blue wires, a combination of primary and secondary colors with soft shades. below the atrium two more floors are developed before reaching the platform. each of them is characterized by a flooring that, after recalling figure 1 garibaldi station. above: floor plan of the mezzanine (in evidence the hypogean square and the group of stairs), cross section on the hypogean square. below: views of some rooms of the station. (drawings from metro-polis, 2006; photos by authors). figura 1 – stazione garibaldi. in alto planimetria del mezzanino (in evidenza la piazza ipogea e il gruppo delle scale), sezione trasversale sulla piazza ipogea. in basso vedute su alcuni ambienti della stazione. (disegni da: metropolis, 2006; foto degli autori). rovescia, sostengono una articolata “chioma” reticolare, che copre la grande piazza pedonale ipogea intorno alla quale si sviluppa una galleria commerciale (figura 1) (amirante, 2011). 3. i colori fluorescenti e forme fluttuanti di karim rashid nella stazione università gli ambienti sotterranei della stazione università, progettati dallo studio newyorkese di karim rashid, presentano colori forti e vivaci in contrasto con i toni del grigio della pietra lavica utilizzati per la sistemazione esterna degli arredi stradali e della pavimentazione ad opera dello studio mendini (d’amato, 2011). per favorire la circolazione e l’orientamento dei viaggiatori vengono utilizzati colori contrastanti come il fucsia e il giallo-verde impiegati già negli ingressi alla stazione da piazza bovio, in cui su ogni mattonella in ceramica bianca rettangolare è impressa una parola del dizionario informatico di colore fucsia nella direzione verso piscinola e giallo-verde verso garibaldi (figura 2). una imponente scultura in acciaio satinato, che richiama le sinapsi del nostro cervello, e colonne lucide nere sagomate con profilo di testa, metafora della mente umana, predominano il grande atrio a cui si accede dopo aver percorso le scale di ingresso. coloratissime figure tridimensionali, sospese nello spazio bianco di un lungo light box costituiscono lo sfondo della scena rendendola ancora più spettacolare. unioni di sfere, croci tubolari, solidi multiformi e curvilinei, che si sovrappongono a figure geometriche piane, propongono combinazioni complementari di colori verde-rosso, violagiallo, arancio-blu; si tratta di colori non saturi, né brillanti la cui luminosità è esaltata dal bianco dello sfondo del pannello. una particolare illuminazione crea un disegno a mesh triangolare che delimita pannelli in acciaio che si riflettono sulla synapsi e su un lucido 107 cultura e scienza del colore color culture and science | 10 | 2018 | 103 118 colors, lights and shapes in the naples underground. the “art stations” of line 1 issn 2384-9568 the atrium, has different colors: first orange and pink, then yellow, pink and light blue and finally, at the level of the platform, it becomes white with black wires. the three levels below are characterized by curved walls, covers with mirrored steel panels, bright leds, through which a homogeneous color diffuses in the underground environment of the subway, which keeps the shades of two basic colors of the station. on the tracks level, wall claddings with shiny silver mosaic alternate with panels made with the lenticular system in which the three-dimensional shapes reproduced with the shades of pink towards piscinola and lime towards garibaldi they seem to move in space as the traveler moves. particular shaped marble benches remind the curvilinear motif of new york studio, as if to underline and celebrate the movement of the train arriving at the station. 4. the bright gray of the lava stone in the “rooms museum” of the municipio station during the works of the municipio station, an huge cultural heritage has been brought to light, consisting of several archaeological finds from the greek, roman, medieval and spanish periods [6]. the municipio station, designed by portuguese architects alvaro siza viera and eduardo souto de moura, connects the old town with the port of naples, making living together in one place the history and contemporary art (siza viera and de moura, 2012). the continuous archaeological discoveries have inevitably caused subsequent design changes, slowing down the completion of the work, which is still only partially usable today. a spartan environment welcomes the traveler to the platform of the train dominated by a brilliant dark gray of the lava stone, contrasted by the white plaster of the tunnel and the paving slabs, covering more than half of the tunnel wall, modeling elegant and simple benches. after passing through the austere environments of fiigure 2 università station. above: mezzanine floor plan and section on the descendants, below: views on some rooms of the station. (drawings from rassegna aniai n.2/2011, photos by authors). figura 2 – stazione università. in alto: pianta del mezzanino e sezione sulle discenderie, seguono vedute su alcuni ambienti della stazione. (disegni da rassegna aniai n.2/2011; foto degli autori). pavimento nero, in cui è raffigurata una maglia con fili verdi, gialli e azzurri, combinazione di colori primari e secondari dalle tenue tonalità. al di sotto dell’atrio si sviluppano altri due piani prima di arrivare alla banchina, ciascuno dei quali è contraddistinto da una pavimentazione che, pur richiamando quella dell’atrio, presenta colori diversi: prima arancione e rosa, poi giallo, rosa e azzurro ed infine, al livello della banchina, diventa bianca con fili neri. sul piano dei binari, rivestimenti parietali con mosaico lucido argentato si alternano a pannelli realizzati con il sistema lenticolare in cui le forme tridimensionali riprodotte con le tonalità del fucsia in direzione piscinola e verde in direzione garibaldi sembrano muoversi nello spazio allo spostarsi del viaggiatore. particolari panchine marmoree sagomate riprendono il motivo curvilineo proprio dello studio newyorkese quasi a sottolineare ed esaltare anch’esse il movimento del treno che arriva in stazione. 4. il grigio brillante della pietra lavica negli “ambienti – museo” della stazione municipio durante i lavori della stazione municipio è stato portato alla luce un immenso patrimonio culturale costituito da diversi reperti archeologici di epoca greca, romana, medievale e spagnola [6]. la stazione municipio, progettata dagli architetti portoghesi alvaro siza viera ed eduardo souto de moura, mette in comunicazione il centro storico con il porto di napoli, facendo convivere in un unico luogo storia e arte contemporanea (siza viera and de moura, 2012). le continue scoperte archeologiche hanno inevitabilmente indotto successive modifiche progettuali, rallentando il completamento dell’opera a tutt’oggi solo parzialmente fruibile. un ambiente spartano accoglie il viaggiatore alla banchina del treno dominata da un brillante grigio scuro della pietra lavica che, contrastato dal bianco dell’intonaco 108 cultura e scienza del colore color culture and science | 10 | 2018 | 103 118 martone m. and papa f. issn 2384-9568 doi: 10.23738/ccsj.i92018.12 two mezzanines, a space at full height appears the traveler, dominated by the simple geometry of the volumes of the stairs internally covered in gray stone. the white inclined planes of the extrados of the ramps and the broken line of the edge of the wall of the stairs bring the traveler’s gaze towards a space that is still not perceptible in all its entirety, from which we can see a “loft of light” that lights up this large well 18 meters deep [7]. fixed and mobile stairs, separated by high walls, where windows called “bean” for their particular shape are opened, in a game of opposite directions, bringing to a large “underground square”, from where the various exit paths depart towards the city and towards the port, some still not completed [8]. a mighty yellow tufa stone wall belonging to the ancient viceregal walls and the incoronata tower is the background to this large square [9] . it is an integral part of the station structure [10]. a video-fresco by the iranian artist michal rovner, projected on a long and high wall, repeats the vesuvius in a personal representation, paying tribute to the city and the history of its territory (aa.vv. metro-polis, 2006). outside, the construction of the underground station has also involved a deeo urban transformation, still not totally completed, characterized by the definition of a “spatial continuum” between piazza municipio and the marittima station, creating an urban axis that from the fountain of neptune reaches the port, having as background, towards the hinterland, the vomero hill with the certosa di s. martino and s. elmo castel (figure 3) (giuliano, 2015). 5. from the intense blue of the sea to the ocher of the earth and to the black of the asphalt in the toledo station of tusquest blanca the toledo station by oscar tusquest blanca is located at the intersection of via diaz and via montecalvario, emphasizing the access to the spanish districts. the station is located for more than half below the sea level, so the “zero altitude” was emphasized through the sudden change of the material used (figure 4). under this altitude, the traveler has the impression of plunging into the depths of the sea, but above he enters into the the rock, evoking the excavation. figure 3 municipio station. from the left: cross section, follow photos of the platform, the central group of stairs and the viceregal wall appeared during the work of the underground excavation. (drawings from carughi, 2012, p. 12. photos by authors). figura 3 – stazione municipio. da sinistra: sezione trasversale, seguono immagini fotografiche della banchina, del gruppo centrale delle scale e della murazione vicereale venuta alla luce durante i lavori dello scavo della metropolitana. (disegni da: rassegna aniai n.12/2011; foto degli autori). f della galleria, dalle lastre della pavimentazione arriva a coprire più della metà della parete del tunnel, modellando al suo interno eleganti e semplici panchine. dopo aver attraversato gli austeri ambienti di due mezzanini, al viaggiatore si presenta uno spazio a tutta altezza, dominato dalla semplice geometria dei volumi delle scale internamente rivestite di pietra grigia. i bianchi piani inclinati dell’estradosso delle rampe e la linea spezzata del bordo del muretto delle scale accompagnano lo sguardo del viaggiatore verso uno spazio ancora non percepibile in tutta la sua interezza di cui si intravede un “soppalco di luce” che illumina dall’alto questo grande pozzo di 18 metri [7]. scale fisse e mobili, separate da alti setti murari in cui si aprono finestre dette a “fagiolo” per la loro particolare forma, combinandosi in un gioco di direzioni opposte, conducono ad una grande “piazza sotterranea”, da dove si dipartono i vari percorsi di uscita verso la città e verso il porto, alcuni ancora non completati [8]. fa da sfondo a questa grande piazza un possente muro di pietra di tufo giallo appartenente all’antica murazione vicereale e al torrione dell’incoronata [9], che costituisce parte integrante della struttura della stazione [10]. un video-affresco dell’artista iraniana michal rovner, proiettato su di una lunga e alta parete riproduce in una personale rappresentazione il vesuvio, rendendo omaggio alla città e alla storia del suo territorio (aa.vv. metro-polis, 2006). all’esterno la costruzione della stazione metropolitana ha comportato, inoltre, una profonda trasformazione urbana, ancora non del tutto completata, caratterizzata dalla definizione di un “continuum spaziale” tra piazza municipio e la stazione marittima, formando un asse urbano che dalla fontana del nettuno arriva fino al porto, avente come sfondo, verso l’entroterra, la collina del vomero con la certosa di s. martino e castel s. elmo (figura 3) (giuliano, 2015). 5. dall’azzurro intenso del mare all’ocra della terra fino al nero dell’asfalto nella stazione di toledo di tusquest blanca la stazione toledo di oscar tusquest blanca si colloca nell’intersezione tra via diaz e via montecalvario, sottolineando l’accesso ai quartieri spagnoli. la stazione si trova per più 109 cultura e scienza del colore color culture and science | 10 | 2018 | 103 118 colors, lights and shapes in the naples underground. the “art stations” of line 1 issn 2384-9568 walking through the station from the docks, the close rooms are in the tones of intense blue. you go through escalators with parapets with a wavy profile, covered with blue mosaic that recall the waves of the sea. then the traveler reaches the wide double-height space where the real ascension path begins, in which the central well, with its geometry that can be traced back to a conical trunk with an elliptical base, brings natural light [11] (www.ediliziaeterritorio. ilsole24ore.com, 2018). three escalators spread out from their structures a light blue dimmed by opal glass while all around the blue mosaic tiles mix with the white ones gradually, but more and more intense towards the zero altitude, reproducing the visual effect of a shaded wall. even the floor is covered by this coating and has a curvilinear trend, but after exceeding the zero level, it becomes in a clear way into a floor with a jagged profile. in an equally abrupt way coating of the walls stay in shades of ocher. the tiles used have a square form, with the sides rotated by 45° related to the zero level [12] and they are arranged to define on the walls an irregular profile which emphasizes the idea of the split rock. in the mezzanine the ocher cladding gives way to black mosaic tiles both on the walls and on the ceiling, which refers to the asphalt of the road. the floor is in anthracite gray lava stone, a color that continues on the surface in the pedestrian square together with the travertine and the red brick for the circular areas, bounded by curvilinear seats [13] (tusquets blanca, 2011). in his ascension path the traveler crosses the cold colors of the blue sea to enter in the warm and yellow colors of the earth, with gradual nuances and shapes that become sinuous by angolar, underlining the cohabitation and proximity of two worlds, that hypogeal or underwater world and the earthly and superficial one. figure 4 toledo station. above: section on the “light crater” and mezzanine floor. below: views of some of the interiors of the station where you can see claddings in with blue and white mosaic tiles, ocher tiles and anthracite gray lava stone. (drawings from tusquets blanca, 2011, p. 6-9. photos by authors). figura 4 – stazione toledo. in alto: sezione sul “cratere di luce” e pianta del mezzanino. in basso: vedute di alcuni ambienti interni della stazione in cui si notano i rivestimenti in mosaici azzurri e bianchi, in maioliche ocra e in pietra lavica grigio antracite. (disegni da: rassegna aniai n. 3/2011; foto degli autori). della metà sotto il livello del mare, pertanto la “quota zero” è stata enfatizzata attraverso il cambio repentino di materiale utilizzato (figura 4). sotto tale quota il viaggiatore ha l’impressione di immergersi nel profondo del mare, al di sopra, invece, entra nella roccia evocando lo scavo. percorrendo la stazione dalle banchine, gli ambienti ad esse adiacenti si attestano sui toni dell’azzurro intenso. si percorrono scale mobili con parapetti dal profilo ondulato, rivestiti di mosaico azzurro che richiamano le onde del mare. si giunge poi nell’ampio spazio a doppia altezza da cui inizia il vero e proprio percorso ascensionale, nel quale il pozzo centrale, dalla geometria riconducibile ad un tronco di cono a base ellittica, porta la luce naturale [11] (www. ediliziaeterritorio.ilsole24ore.com, 2018). tre scale mobili irradiano dalle loro strutture una luce celeste smorzata dal vetro opalino mentre tutto intorno le tessere di mosaico blu si mischiano a quelle bianche in maniera graduale, ma sempre più intensa verso la quota zero, riproducendo l’effetto visivo di una parete sfumata. anche il solaio è ricoperto da questo rivestimento e ha un andamento curvilineo, ma superata la quota zero, si trasforma in modo netto in un solaio dal profilo scalettato. in maniera altrettanto brusca il rivestimento delle pareti si attesta sui toni dell’ocra. le maioliche utilizzate hanno modulo quadrato, con i lati ruotati di 45° rispetto alla quota zero [12] e sono disposte in maniera tale da delineare sulle pareti un profilo irregolare che accentua l’idea della roccia spaccata. nel mezzanino il rivestimento ocra cede il posto a tessere di mosaico nere sia sulle pareti che sul soffitto, che rimanda all’asfalto della strada. il pavimento è in pietra lavica grigio antracite, colore che continua in superficie nella piazza pedonale insieme al travertino e al mattone rosso per le aree circolari, delimitate da sedute curvilinee [13] (tusquets blanca, 2011). il viaggiatore nel suo percorso ascensionale attraversa i colori freddi del blu del mare per entrare in quelli caldi e gialli della terra, in una ricchezza di sfumature graduali e forme 110 cultura e scienza del colore color culture and science | 10 | 2018 | 103 118 martone m. and papa f. issn 2384-9568 doi: 10.23738/ccsj.i92018.12 6. neutral colors and saturated colors in dante station the dante station by gae aulenti is located near the square of the same name [14]. from the level of the iron, a white semigloss glass coating, which covers walls and ceilings, consists of modular slabs with exposed bolts, accompanies the traveler up to the mezzanine level while the floor is in shades of dark gray (figure 5). the rooms are neutral, ready to welcome the colors of the art works that follow each other along the way. the eye is captured by the large mosaic made with vitreous tiles where ellipsoids, pencils and stars are treated with pure and saturated colors such as yellow, red and blue on a blue background, reflecting, partially, on the white ceiling (cascetta and gravagnuolo, 2014). a tangle of red, white and black lines in pistoletto’s work, made on a mirror, seems to capture the traveler who is reflected in it. proceeding along the path of ascent a white wall is the background to the work of kounellis and the color gives way to the gray of the steel paneling of slabs placed side by side, where pieces of beams are anchored. the gray and worn look provide to emphasize a sense of temporary, inducing the traveler to overcome the last flight of stairs from which we can see the reflection of kosuth’s work, a text “written” with neon white tubes. alfano’s canvases also are about in shades of black and gray and are in continuity with the colors of the upper square. the flooring is in etnea stone slabs and cubes, whose ground design follows that of architectures present hemicycle by vanvitelli (cassese, 2011). you are accessed to the square by two glass pavilions [15] rom which the light of the sun and the blue color of the sky enter coloring the stairwells. the white and gray of the steel therefore leave figure 5 dante station. above: mezzanine floor plan, detail of the exit staircase on the square, sections at the two glazed exits and the piazza dante plan. below: views of some indoor and outdoor areas of the station. (drawings from aa.vv. la metropolitana di napoli, 2000; photos by authors). figura 5 – stazione dante. in alto: pianta del mezzanino, dettaglio della scala d’uscita sulla piazza, sezioni in corrispondenza delle due uscite vetrate e planimetria di piazza dante. in basso: vedute di alcuni ambienti interni ed esterni della stazione. (disegni da: aa.vv. la metropolitana di napoli; foto degli autori). che da sinuose si trasformano in spigolose, sottolineando la convivenza e la vicinanza di due mondi, quello ipogeo o subacqueo e quello terreno e superficiale. 6. colori neutri e colori saturi nella stazione dante la stazione dante di gae aulenti si trova in corrispondenza dell’omonima piazza [14]. dalla quota del ferro un rivestimento in vetro semilucido bianco, che interessa pareti e soffitto, costituito da lastre modulari con bullonature a vista, accompagna il viaggiatore fino alla quota del mezzanino mentre il pavimento è sui toni del grigio scuro (figura 5). gli ambienti si presentano neutri, pronti ad accogliere i cromatismi delle opere d’arte che si susseguono lungo il percorso. l’occhio è catturato dal grande mosaico realizzato con tessere di pasta vitrea in cui ellissoidi, matite e stelle sono trattate con colori puri e saturi come il giallo, il rosso e il blu su un fondo azzurro, riflettendosi, seppur in parte, sul soffitto bianco (cascetta, gravagnuolo, 2014). un groviglio di linee rosse, bianche e nere nell’opera di pistoletto, realizzata su uno specchio, sembra catturare anche il viaggiatore che ci si riflette. procedendo lungo il percorso di risalita una parete bianca fa da fondo all’opera di kounellis e il colore lascia il posto al grigio della pannellatura di lastre d’acciaio affiancate l’una all’altra, cui sono ancorati spezzoni di travi. il grigio e l’aspetto usurato contribuiscono ad accentuare un senso di precarietà, inducendo il viaggiatore a superare l’ultima rampa di scale dalla quale si intravede il riflesso dell’opera di kosuth, un testo “scritto” con tubolari bianchi al neon. anche le tele di alfano si attestano sui toni del nero e del grigio e sono in continuità con i colori della piazza superiore. 111 cultura e scienza del colore color culture and science | 10 | 2018 | 103 118 colors, lights and shapes in the naples underground. the “art stations” of line 1 issn 2384-9568 no room for any other color except to underline the art works. 7. from the totalizing white of coverings to the black of jodice’s works in museo station the museo station designed by gae aulenti, is located, together with the cavour station, in the large and stretchedspace that is the homonymous square. when you go through the station from the underground level, you come across the same colors as in the dante station. the white glass cladding, with modular panels fixed with studs, lines both the island dock, whose lowered vaulted ceiling is covered with white porcelain steel, and all the rooms that bring to the mezzanine[16]. the floor in the various rooms is dark gray, interrupted by the yellow rubber paths for blind people. the monochromatic nature of white and the rhythmic scanning of the walls creates a suspended atmosphere in the mezzanine, emphasized by the light filtered by the large windows of the roofs that allow to reflect the colors of the sky on the semi-gloss walls, softening the white and creating an ambient in the soft tones of light blue. in this time “blocked” even the two sculptures accentuate with their dimensions and their colors this sense of suspension. this is the cast of hercules farnese in fiberglass and the bronze cast of the horse head of the “carafa” [17] . walking along the corridors that lead to the national archaeological museum, on the white walls, large panels host photographs of sculptures captured together with their shadows by mimmo jodice, who admit the exclusive use of black and white. no room is given to other colors, which instead present themselves with all their force in the volumes above ground of the figure 6 museo station. on top: roof plan, elevation and mezzanine section. below: the glass roof and the white glass cladding, the second entrance with the horse head of the “carafa”, the sequence of black and white photographs by mimmo jodice and the pompeian red exterior volume. (drawings from aa.vv. la metropolitana di napoli, 2000; photos by authors). figura 6 – stazione museo. in alto: pianta della copertura, prospetto e sezione del mezzanino. in basso: la copertura vetrata e il rivestimento in vetro bianco, il secondo ingresso con la testa di cavallo dei “carafa”, la sequenza di fotografie in bianco e nero di mimmo jodice e il volume esterno rosso pompeiano. (disegni da aa.vv. la metropolitana di napoli, 2000; foto degli autori). la pavimentazione è in pietra etnea a lastre e cubetti, il cui disegno a terra segue quello delle architetture presenti nell’emiciclo vanvitelliano (cassese, 2011). alla piazza si accede da due padiglioni in cristallo [15] da cui la luce del sole e il colore azzurro del cielo penetrano colorando i corpi scala. il bianco e il grigio dell’acciaio non lasciano dunque spazio a nessun altro colore se non per sottolineare le opere d’arte. 7. dal bianco totalizzante dei rivestimenti al nero delle opere di jodice nella stazione museo la stazione museo realizzata da gae aulenti, si colloca, insieme alla stazione cavour, nel grande spazio allungato che costituisce l’omonima piazza. nel percorrere la stazione dal livello interrato ci si imbatte negli stessi colori presenti nella stazione dante. il rivestimento in vetro bianco, a pannelli modulari fissati con borchie, fodera sia la banchina ad isola, il cui soffitto a volta ribassata è rivestito di acciaio porcellanato bianco, sia tutti gli ambienti che conducono verso il mezzanino [16]. il pavimento nei vari ambienti è di colore grigio scuro interrotto dai percorsi in gomma gialla per i non vedenti. la monocromaticità del bianco e la scansione ritmica delle pareti contribuisce a creare nel mezzanino una atmosfera sospesa nel tempo, accentuata dalla luce filtrata dalle ampie vetrate delle coperture che permettono di riflettere i colori del cielo sulle pareti semilucide, smorzando il bianco e creando un ambiente sui toni soffusi del celeste. in questo tempo “bloccato” anche le due sculture presenti accentuano con le loro dimensioni e i loro colori questo senso di sospensione. si tratta del calco d’ercole farnese in vetroresina e il calco bronzeo della testa di cavallo dei “carafa” [17]. proseguendo lungo i corridoi che conducono 112 cultura e scienza del colore color culture and science | 10 | 2018 | 103 118 martone m. and papa f. issn 2384-9568 doi: 10.23738/ccsj.i92018.12 station. the small architectures, whose masonry walls have the same orientation of the nearby national museum, are made of vesuvian stone and plastered with pompeian red, the only color that characterizes the work, to which attention is granted and that monopolizes the final scene at street level, remind the color of the nearby museum. (figure 6) (aa.vv., 2000). 8. combinations of primary, secondary and tertiary colors in the panels of sol le wit in the materdei station the platforms at materdei station, designed by the mendini studio, welcome the traveler through a set of silk-screen images of famous contemporary artists who, side by side, create real exhibition walls. the traveler is involved in a chromatic effect that is strong and decisive like the vibrant composition of george sowden, who combines chairs, telephones, lamps and fabrics in a harmonious succession of saturated colors now rather tenuous and calm like the flowers with shades crayons that hide the antipersonnel mines of mathelda balatresi. bronze chandeliers and massive marble benches emphasize the warm tone of the colors found in the underground environment. behind the platform there is a wide corridor characterized by four long colorful walls of sol le wit, composed of a set of polychrome panels, in which various combinations of primary, secondary and tertiary colors alternate with the addition of gray. the same range of colors is proposed by the author in a particular cylindrical composition, placed at the head of the corridor, in which the colors take on a particular three-dimensional shape of a spire. small green-yellow, azure and ocher mosaic tiles cover the walls of mobile and fixed paths that communicate with the floor above. a beautiful mosaic with ceramic reliefs, where blue colors predominate, in different shades, overlays the group of stairs and, framed in a figure 7 matedei station. above: mezzanine plan and plan at the level of the platoforms with cross section. following are views of some indoor and outdoor environments of the station. (drawings from aa.vv. la metropolitana di napoli, 2000; photos by authors). figura 7 stazione materdei. in alto: planimetria del mezzanino e planimetria a livello delle banchine con sezione trasversale. seguono vedute di alcuni ambienti interni ed esterni della stazione. (disegni da aa.vv. la metropolitana di napoli, 2000; foto degli autori). al museo archeologico nazionale, sulle pareti bianche grandi pannelli ospitano fotografie di sculture immortalate insieme alle loro ombre di mimmo jodice, che ammettono l’uso esclusivo del bianco e nero. non è concesso alcuno spazio ad altri cromatismi, che invece si presentano con tutta la loro forza nei volumi fuori terra della stazione. le piccole architetture, le cui quinte murarie hanno lo stesso orientamento del vicino museo nazionale, sono realizzate in pietra vesuviana e intonacate di rosso pompeiano, l’unico colore che caratterizza tutto l’intervento a cui è concessa attenzione e che monopolizza la scena finale alla quota stradale, richiamando il colore del vicino museo (figura 6) (aa.vv., 2000). 8. combinazioni di colori primari, secondari e terziari nei pannelli di sol le wit nella stazione materdei le banchine della stazione di materdei, progettata dallo studio mendini, accolgono il viaggiatore attraverso un insieme di immagini serigrafiche di celebri artisti contemporanei che, affiancate l’una all’altra, creano vere e proprie pareti espositive. il passeggero rimane coinvolto in un effetto cromatico ora forte e deciso come la vivace composizione di george sowden, che accosta sedie, telefoni, lampade e tessuti in un armonico susseguirsi di colori saturi ora invece tenue e pacato come i fiori dalle tonalità pastello che nascondono mine antiuomo di mathelda balatresi. lampadari bronzei e massicce panchine di marmo accentuano le tonalità calde dei colori presenti nell’ambiente sotterraneo. alle spalle della banchina si estende un ampio corridoio caratterizzato da quattro lunghe pareti coloratissime di sol le wit, composte da un insieme di pannelli policromi, in cui si alternano varie combinazioni di colori primari, secondari e terziari con l’aggiunta del grigio. la stessa gamma dei colori viene proposta dall’autore in una particolare composizione cilindrica, posta alla testata del corridoio, in cui i colori 113 cultura e scienza del colore color culture and science | 10 | 2018 | 103 118 colors, lights and shapes in the naples underground. the “art stations” of line 1 issn 2384-9568 golden frame, represents a marine scene with particular figures and a face of pulcinella [18]. the traveler arrives in the atrium of the station attracted by natural light coming from a steelspire dome with colored glass, with at the base a mosaic covering of marine scenes. the tones of green and blue predominate in the whole environment. a flight of stairs, where the parietal covering continues with a colored mosaic of the underlying level, connects the interior with the outside and culminates with a trilithic structure surmounted by a star with green and yellow tiles. the project by mendini studio for materdei station also includes the layout of the square, which is valorized with new furnishings and art works art in which the steel spire, similar to the one designed by mendini for the salvator rosa station, predominates. (figure 7) (mendini, 2000). 9. cold colors and light effects in vanvitelli station the vanvitelli station was restyled in 2005 by lorenzo and michele capobianco architects, who renovated the rooms through a careful light and color play and the inclusion of art works. the station is spread over three levels [19] and starting from the iron level the platforms have a black rubber floor where paths in relief for the blind people are grafted. nearby two fixed staircases hat bring to the upper floors, there are two large stone and glass paste mosaics in bright colors by isabella ducrot, where the three primary colors: red, yellow and blue and the secondary color: green are alternated. both mosaics follow in the façade the sharp contour of the ceiling and interrupt the intensity of the black surrounding them. the escalators bring directly to the mezzanine floor and allow you to appreciate two large steel stars by zorio placed on the metallescent white walls of the intermediate floor, color that gives them a backdrop. after reaching the mezzanine, the floor is in shades of black and gray and you can admire along the side corridors, when you are leaving the station, the black and white photographs by basilico, the quiet and subdued colors by barbieri and the prints by piasani, with alternated large spots of black, red and blue. staying on the mezzanine level, on the balcony, the long bronze-colored wall is occupied by paolini’s theatrical installation: a large boulder hooked to steel wires that breaks the glass. the tones of gray, cold materials such as steel and glass and subdued lighting govern these spaces, permeate them without granting any space in bright colors except colors of mosaics, giving up the place only to the cold and intense blue, main color of the station in the descent from the mezzanine to the intermediate floor. the tones of gray, cold materials such as steel assumono una particolare forma tridimensionale a guglia. piccole tessere di mosaico di colore verde-giallo, azzurro e ocra rivestono le pareti dei percorsi mobili e fissi che comunicano con il piano sovrastante. un bel mosaico con rilievi in ceramica, in cui prevalgono i colori azzurri nelle diverse sfumature, sormonta il gruppo delle scale e, inquadrato in una cornice dorata, rappresenta una scena marina con particolari figure e un volto di pulcinella [18]. il viaggiatore giunge nell’atrio della stazione attratto dalla luce naturale proveniente da una cupola a guglia in acciaio con vetri colorati, con alla base un rivestimento a mosaico di scene ancora marine. in tutto l’ambiente prevalgono i toni del verde e dell’azzurro. una rampa di scale, in cui continua il rivestimento parietale con mosaico colorato del livello sottostante, collega gli ambienti interni con l’esterno e culmina con una struttura trilitica sormontata da una stella con tessere verdi e gialle. il progetto dello studio mendini della stazione di materdei comprende anche la sistemazione della piazza che viene arricchita di nuovi arredi e di opere d’arte in cui predomina la guglia di acciaio simile a quella progettata sempre da mendini per la stazione di salvator rosa (figura 7) (mendini, 2000). 9. colori freddi e gioco di luci nella stazione vanvitelli la stazione vanvitelli fu oggetto di restyling nel 2005 ad opera degli architetti lorenzo e michele capobianco, che ne rinnovarono gli ambienti attraverso un attento gioco di luci e colori e l’inserimento di opere d’arte. la stazione si articola su tre livelli [19] e partendo dal piano del ferro le banchine presentano un pavimento in gomma nera su cui si innestano i percorsi in rilievo di colore grigio per i non vedenti. in corrispondenza delle due scale fisse che conducono ai piani superiori, sono collocati due grandi mosaici in pietra e pasta vitrea dai colori vivaci di isabella ducrot, in cui si alternano i tre colori primari: rosso, giallo e blu e il colore secondario: verde. entrambi i mosaici seguono nel prospetto l’andamento spigoloso del controsoffitto e interrompono l’intensità del nero che li circonda. le scale mobili, invece, conducono direttamente al piano del mezzanino e permettono di apprezzare le due grandi stelle in acciaio di zorio collocate sulle pareti bianco metallescente del piano intermedio, colore che fa loro da quinta. raggiunto il mezzanino il pavimento si mantiene sui toni del nero e del grigio e si ammirano lungo i corridoi laterali in uscita dalla stazione le fotografie in bianco e nero di basilico, quelle dai cromatismi pacati e sommessi di barbieri e le stampe di piasani, in cui si alternano grandi macchie di colore nero, rosso e azzurro. rimanendo alla quota del 114 cultura e scienza del colore color culture and science | 10 | 2018 | 103 118 martone m. and papa f. issn 2384-9568 doi: 10.23738/ccsj.i92018.12 figure 9 avove: representations of the metropolitan route of line 1 highlighted on the city plan and in the linear scheme. key: 1. garibaldi 2. università 3. municipio 4. toledo 5. dante 6. museo 7. materdei 8. vanvitelli. on the right: the transport network in the metropolitan area of naples. (drawings from aa.vv. la metropolitana di napoli, 2000). figura 9 – rappresentazioni del percorso metropolitano della linea 1 evidenziato sulla planimetria della città e nello schema lineare. legenda: 1. garibaldi 2. università 3. municipio 4. toledo 5. dante 6. museo 7. materdei 8. vanvitelli. a destra, in basso: la rete dei trasporti nell’area metropolitana di napoli. (disegni da: aa.vv. la metropolitana di napoli, 2000). figure 8 vanvitelli station: views of some station interiors. (photos by authors). figura 8 – vedute di alcuni ambienti interni della stazione. (foto degli autori). and glass and subdued lighting govern these spaces, permeating them without granting any space in bright colors except those of the mosaics, giving place only to the cold and intense blue, color that is the protagonist of the station during the the descent from the mezzanine to the intermediate level. in fact, a wide blue vault dominates the traveler recalling the blue of the mediterranean sky, illuminated by the light spiral by merz [20]. in this way there is the feeling that the hypogeal space carries with it the “superficial space” (figure 8) (mendini, 2000). 10. conclusions the art stations of line 1 show the principles of the station renaissance architectural movement, developed in europe since 1980, aimed at the redevelopment of underground and railway stations and the design of new ones, aiming at architectural quality, aesthetics, respect of the historical identity of the urban areas where they are made [21] . a new way of considering the railway station (cascetta, cartenì, henke, 2014) has developed not only a node of a transport system, but also a cultural center for social exchanges, shopping and catering, taking an active part in the life of the city and its citizens. within the project of the regional metropolitan system of campania, the possibility of offering to naples a metropolitan service characterized by high architectural and aesthetic standards, competitive at european level, has been concretized (tusquets blanca, 2011). the color has a key and decisive role not only in the architectural composition of the spaces, but also in making the underground rooms, placed at depths even fifty meters below the street level, brighter, welcoming and pleasant. every station mezzanino, sul ballatoio, la lunga parete color bronzo è occupata dalla teatrale istallazione di paolini: un grande masso agganciato a fili d’acciaio che rompe il vetro. i toni del grigio, i materiali freddi come l’acciaio e il vetro e una illuminazione sommessa governano questi spazi, li pervadono senza concedere alcuno spazio a colori accesi se non a quelli dei mosaici, cedendo il posto solo al freddo e intenso blu, colore protagonista della stazione nella discesa dal mezzanino al piano intermedio. una ampia volta di colore blu sovrasta, infatti, il viaggiatore richiamando l’azzurro del cielo mediterraneo, illuminato dalla spirale luminosa di merz [20]. in tal modo si ha la sensazione che lo spazio ipogeo trascini con sé lo “spazio superficiale” (figura 8) (mendini, 2000). 10. conclusions le stazioni dell’arte della linea 1 esprimono i principi del movimento architettonico station renaissance sviluppatosi in europa già dal 1980, rivolti alla riqualificazione delle stazioni dismesse metropolitane e ferroviarie e alla progettazione di quelle nuove mirando alla qualità architettonica, all’estetica, al rispetto dell’identità storica delle aree urbane in cui vengono realizzate [21]. si è venuto quindi anche a sviluppare un nuovo modo di concepire la stazione ferroviaria (cascetta, cartenì, henke, 2014), non più solo nodo di un sistema dei trasporti, ma anche centro culturale, di scambi sociali, di shopping e di ristorazione, partecipando attivamente alla vita della città e dei cittadini. all’interno del progetto del sistema metropolitano regionale della campania si è concretizzata la possibilità di offrire alla città di napoli un servizio metropolitano caratterizzato da alti standard architettonici ed estetici, competitivo a livello europeo (tusquets blanca, 115 cultura e scienza del colore color culture and science | 10 | 2018 | 103 118 colors, lights and shapes in the naples underground. the “art stations” of line 1 issn 2384-9568 is characterized by specific colors, chromatic effects and special lights that help the passenger to recognize the city above, identifying by the color the underground station’s name and its urban layout (figure 9). the subterranean colors are summarized in figure 10 in a representation with a square mesh which proposes for each station analyzed a sampling of colors of the railway path, identifying the main colors / object. next to the mesh we selected the basic colors based on the main textures already selected, to highlight the color choices that characterize the underground spaces in the main stations of line 1 of figure 10 sampling of underground colors-shape of line 1 naples subway. each number corresponds to eight stations represented in sequence starting from garibaldi station. (compare fig legend fig.9). on the right the basic colors are highlighted. (photos by authors). figura 10 campionatura dei colori-forma sotterranei della linea 1 della metropolitana di napoli. ai numeri corrispondono le otto stazioni rappresentate in sequenza a partire dalla stazione garibaldi (cfr. legenda figura 9). a destra sono evidenziati i colori base.; foto degli autori). 2011). il colore assume un ruolo fondamentale e decisivo non solo nella composizione architettonica degli spazi, ma anche e soprattutto nel rendere gli ambienti sotterranei, posti a profondità anche di cinquanta metri sotto il livello stradale, più luminosi, accoglienti e gradevoli. ogni stazione è contraddistinta da precise tonalità di colori e da effetti cromatici e di luci particolari che aiutano il passeggero a riconoscere anche sottoterra la città che sta sopra, individuando dal colore il nome della stazione e la sua collocazione planimetrica urbana (figura 9). i colori sotterranei sono sintetizzati nella figura 116 cultura e scienza del colore color culture and science | 10 | 2018 | 103 118 martone m. and papa f. issn 2384-9568 doi: 10.23738/ccsj.i92018.12 naples subway, based mainly on bright colors, “comfortable and attractive” [22] . funding this research did not receive any specific grant from funding agencies in the pubblic, commercial, or-not-for-profit sectors. conflict of interest the authors declare no conflict of interest including financial, personal or other relationship with other people and organizations within three years of beginning the submitted work that could inappropriately influence, or be perceived to influence, this work notes this paper, expanded in some paragraphs and with some changes in the text and in the figures, was published by the authors with the title: m. martone, f. papa. “i colori sotterranei. le stazioni dell’arte della linea 1 della metropolitana di napoli”, in: maurizio rossi and veronica marchiafava (edited by). color and colorimetry multidisciplinary contributions, vol. x a, proceedings of the tenth conference of color, genova, 11-12 september 2014, santarcangelo di romagna (rn): maggioli editore, 2014. p. 365-376. isbn 978-88-916-0437-8. the texts refered to paragraphs n. 1, 2, 3, 4, 8 and 10 are by maria martone, while those refered to paragraphs n. 5, 6, 7 and 9 are by floriana papa. [1] art critic, he has promoted contemporary art with exhibitions, events and essays. in 1993 he was the general curator of the venice biennale. he defined the subway art stations as a “mandatory museum” (aa.vv. metro-polis, 2006, p. 20). [2] we thank eng. de risi of m. n., metro of naples s.p.a., for having us important documentary material related to the projects of the art stations for the realization of this paper. [3] the garibaldi station is an important transport node on iron and rubber connecting to the central station, to the vesuviane lines of the eav (ente autonomo volturno), to the underground line 2 and to the regional and extra-regional bus terminus. [4] the two great works, entitled “stazione 1” and “stazione 2”, by michelangelo pistoletto represent for the author “a door that connects art and life”. (http://www.anm.it/, giugno 2018). [5] they are words coined in the last fifty years as: virtual, database, software, network and others. [6] among the numerous archaeological finds there are three shipwrecks that testify to a flourishing maritime activity in the greek-roman port basin of neapolis. a building of the xiii-xiv century came to light in the north of the castle. a residence with frescoes attributed to the del balzo family was identified. as evidence of the ramparts of the aragonese citadel is the bulwark with a turret emerged from the excavations and incorporated into the wall structure of the station (siza viera and de moura, 2012). [7] the whole station reaches a depth of 40 meters. 10 in una rappresentazione con maglia quadrata che propone per ogni stazione analizzata una campionatura di colori del percorso ferrato, individuando i colori/oggetto principali. accanto alla maglia sono riportati i colori base tra quelli utilizzati nei colori principali già selezionati, per evidenziare le scelte cromatiche che caratterizzano gli spazi sotterranei delle principali stazioni della linea 1 della metropolitana di napoli, basate principalmente su colori vivaci, “confortevoli ed attraenti” [22]. note il presente contributo, ampliato in alcuni paragrafi e con alcune variazione nel testo e nelle figure, è stato pubblicato dagli autori con il titolo: m. martone, f. papa. i colori sotterranei. le stazioni dell’arte della linea 1 della metropolitana di napoli, in: maurizio rossi e veronica marchiafava (a cura di). colore e colorimetria contributi multidisciplinari, vol. x a, atti della decima conferenza del colore, genova, 11-12 settembre 2014, santarcangelo di romagna (rn): maggioli editore, 2014. p. 365-376. isbn 978-88-916-0437-8. i testi relativi ai paragrafi n.ri 1, 2, 3, 4, 8 e 10 sono di maria martone, mentre quelli relativi ai paragrafi n.ri 5, 6, 7 e 9 sono di floriana papa. [1] critico d’arte, ha promosso l’arte contemporanea con mostre, eventi e saggi. nel 1993 è stato il curatore generale della biennale di venezia. ha definito le stazioni d’arte della metropolitana come un “museo obbligatorio” (aa. vv. metro-polis, 2006, p. 20). [2] si ringrazia l’ing. antonello de risi della m. n., metropolitana di napoli s.p.a., per aver messo a disposizione importante materiale documentario relativo ai progetti delle stazioni d’arte per la realizzazione di questo contributo. [3] la stazione garibaldi rappresenta un importante nodo del trasporto su ferro e su gomma collegandosi alla stazione centrale, alle linee vesuviane dell’eav (ente autonomo volturno), alla linea 2 della metropolitana e ai capolinea di autobus regionali ed extraregionali. [4] le due grandi opere, dal titolo “stazione 1” e “stazione 2”, di michelangelo pistoletto rappresentano per l’autore “una porta che mette in comunicazione arte e vita” (http://www.anm. it/, giugno 2018). [5] si tratta di parole coniate negli ultimi cinquanta anni come: virtual, database, software, network ed altre ancora. [6] tra i numerosi reperti archeologici ritrovati ricordiamo tre relitti di navi a testimonianza di una fiorente attività marittima nel bacino portuale greco-romano di neapolis. un comparto edilizio del xiii-xiv secolo è venuto alla luce a settentrione del castello tra cui è stata identificata una residenza con affreschi attribuita alla famiglia del balzo. a testimonianza della cinta bastionata della cittadella aragonese è l’antemurale con torrione emerso dagli scavi e inglobato nella struttura muraria della stazione (siza viera and de moura, 2012). [7] tutta la stazione raggiunge, invece, una profondità di 40 metri. [8] da questo ambiente parte anche il collegamento con la linea 6. 117 cultura e scienza del colore color culture and science | 10 | 2018 | 103 118 colors, lights and shapes in the naples underground. the “art stations” of line 1 issn 2384-9568 [9] from this environment the connection with line 6 starts. [10] the curtain wall with the incoronata towers and the molo and with the front ditch are they are part of what remains of the 16th century castel nuovo defensive system, marking the image of this part of the city up to the unification of italy. [11] the 37 m deep well is the result of an accidental suggestion born after the first inspection of the catalan architect in the yard, and during which, at the sight of the well used for the extraction of the volcanic material, he decided not to close it after the work of load of the material, but to preserve it giving it the image of “crater”, through which the light would have penetrated from the road to the depths (tusquets blanca, 2011). [12] some tiles have further inlays of blue narrow and long bands that break the compactness of the ocher color, almost to simulate the presence of “impurities” of the ground due to deposition material. in addition, walls and ceilings are painted yellow, recalling the “geological layer” in tuff. [13] the exit on via diaz has a large pedestrian square on the surface, almost an “open-air living room”. also the second exit, in piazzetta montecalvario, in the spanish quarters, is characterized by a raised square, totally treated with dark gray lava stone and it can be reached by wide steps, where the street furniture annexes the trees and recalls the blue color of the circular seats inside the station. [14] the dante station is located 30 m deep under the hemicycle designed by vanvitelli between 1757 and 1765, and in a tangent position with respect to via toledo. [15] the pavilions with shape of a “v” ensure the visibility of the square from any side of it. two glazed exits that are symmetrical if they are refered to the axis of the square hug the white statue of dante placed in the center. [16] the glass cladding, both of the ceilings and of the walls, presents reduced modules with metal strips where the lighting fixtures and the signs are located. [17] the two sculptures are respectively located in the atrium, visible as soon as you get off the escalators and the other in the second entrance of the station, in adjacent rooms. the “carafa” head is visible from the outside because it is aligned with the access ramp. [18] the monumental mosaic is a work by sandro chia, while the nearby composition of solids on a white wall is the work by ettore spalletti. [19] the station is about 20 m. deep if compared to the road level. (https://divisare.com/projects/6285lorenzo-capobianco-restyling-della-stazione-di-piazzavanvitelli-linea-1-metropolitana-di-napoli, giugno 2018). [20] the bright blue spiral by mario merz in sandblasted neon, paper and polycarbonate, is inspired by the fibonacci series which also inspires the installation on the curved white wall of the intermediate floor, where figures of prehistoric animals appear. [21] there are numerous examples in europe of new or renovated subways, selected by the english newspaper telegraph which has proclaimed toledo station as one of the most beautiful stations in europe. [22] the station renaissance architectural movement defines the real design standards for new projects, among which reference is made to the use of “comfortable and [9] la cortina muraria con i torrioni dell’incoronata e del molo e con l’antistante fossato fanno parte di ciò che rimane del sistema difensivo di castel nuovo del xvi secolo, segnando l’immagine di questa parte della città fino all’unità d’italia. [10] altri spazi museali saranno in seguito aperti per accogliere i numerosi reperti venuti alla luce. [11] il pozzo profondo 37 m è il frutto di una accidentale suggestione nata a seguito del primo sopralluogo in cantiere dell’architetto catalano, e durante il quale, alla vista del pozzo funzionale all’estrazione del materiale vulcanico, decise di non chiuderlo dopo i lavori di carico del materiale, ma di conservarlo attribuendogli l’immagine di “cratere”, attraverso il quale la luce sarebbe penetrata dalla quota stradale fino in profondità (tusquets blanca, 2011). [12] alcune delle maioliche hanno ulteriori intarsi di fasce strette e lunghe di colore azzurro che spezzano la compattezza del color ocra, quasi a simulare la presenza di “impurità” del terreno dovuto a materiale di deposizione. inoltre pareti e solai sono dipinti di giallo, ricordando lo “strato geologico” in tufo. [13] l’uscita su via diaz presenta in superficie una grande piazza pedonale, quasi un “salotto a cielo aperto”. anche la seconda uscita, in piazzetta montecalvario, nei quartieri spagnoli, è caratterizzata da una piazza rialzata, trattata interamente con pietra lavica grigio scuro ed è raggiungibile da ampie gradonate, in cui l’arredo urbano integra le alberature e richiama con il colore blu delle sedute circolari l’interno della stazione. [14] la stazione dante di trova ad una profondità di circa 30 m esattamente sotto l’emiciclo progettato da vanvitelli tra il 1757 e il 1765, e in posizione di tangenza rispetto a via toledo. [15] i padiglioni a forma di “v” assicurano la visibilità della piazza da qualunque lato si salga. le due uscite vetrate esattamente simmetriche rispetto all’asse della piazza abbracciano la bianca statua di dante posta al centro. [16] il rivestimento in vetro, sia dei soffitti che delle pareti, presenta dei moduli ridotti con fasce metalliche in cui sono alloggiati i corpi illuminanti e la segnaletica. [17] le due sculture di trovano rispettivamente una nell’atrio, visibile appena sbarcati dalle scale mobili e l’altra nel secondo ingresso della stazione, in ambienti tra loro adiacenti. la testa “carafa” è visibile già dall’esterno poiché in asse con la rampa di accesso. [18] il monumentale mosaico è opera di sandro chia, mentre la vicina composizione di solidi su parete bianca è opera di ettore spalletti. [19] la stazione raggiunge una profondità rispetto al piano stradale di circa 20 m (https://divisare.com/projects/6285lorenzo-capobianco-restyling-della-stazione-di-piazzavanvitelli-linea-1-metropolitana-di-napoli, giugno 2018). la spirale blu luminosa di mario merz in neon sabbiato, carta e policarbonato, è ispirata alla serie di fibonacci che ispira anche l’istallazione sulla parete curva e bianca del piano intermedio, su cui incombono figure di animali preistorici. [20] numerosi sono gli esempi in europa di metropolitane nuove o ristrutturate selezionate dal quotidiano inglese telegraph che ha proclamato la stazione di “toledo” come una delle stazioni più belle d’europa. [22] vengono definiti dal movimento architettonico station renaissance anche dei veri e propri standard progettuali 118 cultura e scienza del colore color culture and science | 10 | 2018 | 103 118 martone m. and papa f. issn 2384-9568 doi: 10.23738/ccsj.i92018.12 attractive colors” (cascetta, cartenì, henke, 2014). bibliography aa.vv. (2000). la metropolitana di napoli, nuovi spazi per la mobilità e la cultura, napoli: electa. aa.vv. metro-polis. (2006). “la sfida del trasporto su ferro a napoli e in campania”. allegato alla rivista abitare, n. 464. amirante, r. (2011). “metropolitana garibaldi. come trasformare un piazzale in tante piazze”. in: “rassegna aniai” n. 4, pp. 16-21. cascetta, e., gravagnuolo, b. (a cura di) (2014). le metropolitane e il futuro delle città. atti del convegno. napoli, clean edizioni. cascetta, e. cartenì, henke, a. i. (2014) ‘qualità delle stazioni, estetica e attrattività del trasporto ferroviario: evidenze empiriche e modelli matematici’ ingegneria ferroviaria, 4/04, edita dal collegio ingegneri ferroviari italiani. cassese, g. (a cura di). (2011). la conservazione dell’arte pubblica in italia, il caso del metrò dell’arte a napoli, napoli: editrice politecnica napoli. d’amato, g. (2011). “la stazione della metropolitana di piazza bovio”. rassegna aniai n. 2, pp. 12-15. giuliano, b. (2015). “la stazione delle tre a: nel metrò napoli apre «municipio» di siza e de mura”. edilizia e territorio. quotidiano del sole 24 ore, 26 http://www.ediliziaeterritorio.ilsole24ore.com/art/ progetti-e-concorsi/2015-05-26/stazione-metro-napolia p re 1 0 2 8 3 2 . p h p ? u u i d = a b y r c n 8 l & re f re s h _ c e = 1 (accessed: june 2018). mendini, a. (2000). “salvator rosa e materdei, le stazioni dell’arte”. aa.vv., 2000, pp. 100-117. siza viera, a., de moura, e. s. (2012). “dossier. la metropolitana di napoli. stazione di piazza municipio”. rassegna aniai, n. 1/2, pp. 4-7. tusquets blanca, o. (2011). “la stazione toledo montecalvario, un salotto urbano all’aperto”. rassegna aniai n. 3, pp. 4-9. per le nuove realizzazioni tra cui viene fatto anche il riferimento all’utilizzo di “colorazioni confortevoli ed attraenti” (cascetta, cartenì, henke, 2014). 55 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140107 digital struggles for film restoration: la battaglia dall’astico al piave serena bellotti, simone venturini dipartimento di studi umanistici e del patrimonio culturale (dium) università degli studi di udine bellotti.serena@spes.uniud.it, simone.venturini@uniud.it corresponding author: serena bellotti (bellotti.serena@spes.uniud.it) abstract our contribution is focused on the ongoing reconstruction and restoration of la battaglia dall'astico al piave (1918, 35mm, tinted and toned, mt 1255), by the university of udine in collaboration with la cineteca del friuli, istituto luce and cineteca italiana, and supported by mic. to date, three versions are documented: the 1918 italian and french versions, both realized by the italian royal army film department, and a further version released in 1927 which was probably re-edited by istituto luce. archival prints collected after a first survey of the film archives have been used to reconstruct the text on proxies, with the help of edge-to-edge and “repro-set” documentation and the other non-film materials. the restoration is being carried out through the digital intermediate route, using witness from kinoatelje (“k”) as the main reference to reconstruct the order of the scenes and the colour palette for the digital desmet procedure. the aim of our contribution is twofold: on one hand, we highlight specific restoration and reconstruction issues; on the other hand, we focus on the reloading and reframing of the long-standing and sensitive field of digital research and the educational-oriented critical edition of films, in order to document the restoration and reconstruction process and give a wider account of the material, visual and cultural history of film as a set of apparatus, discourses and practices, proposed here through an innovative digital design and environment and following new interdisciplinary approaches. keywords italian wwi film heritage, film restoration, film reconstruction, film philology, critical editions of film received 01/09/2021; revised 09/12/2021; accepted 19/03/2022 digital struggles for film restoration: la battaglia dall’astico al piave 56 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140107 1. introduction la battaglia dall'astico al piave [1] was made by the italian royal army film department in 1918. the film testifies the days between 15 and 29 june 1918 and shows many important moments of the battle, from the attack on montello to the recapture of the village of nervesa. three versions have been documented to date: the 1918 italian and french versions, both made by the military film department, and a further version, renamed ta pum, released in 1927 and still in circulation around 1930–33 at least, which was probably re-edited by istituto luce. starting from archival prints, the project aims to make a textual reconstruction of the first italian edition of 1918 with the help of edge-to-edge, “repro-set” recordings and other non-film materials. the restoration is being carried out through the digital intermediate route, and the result will then be recorded back on film to reproduce the tinting and toning through the desmet method and using witness preserved by associazione kinoatelje (from now, simply called “k”) as the main reference (see table 1 above). according to the philology of texts, "witnesses" are "all the facts and objects that have transmitted the work through time, from its origin to us" (chiesa, 2020). then the 35mm colour print will be scanned so that there is conformity at least between the photochemical and digital theatrical copies, which could not be achieved otherwise. at the same time, we will give an historical and visual account of the other versions, especially the 1927 re-release, through the digital environment we are designing for a digital critical edition of the film. the aim of the project is to reconstruct the first italian edition of 1918 and at the same time to give an historical and visual account of the other versions, especially the 1927 re-release. 2. objective “a (film) restorer according to the contemporary definition of the term has always relied on and been involved in philology. and the final aim of the philologist is the critical edition” (marotto, 2008). therefore, we will present our approach to film reconstruction, showing the numerous similarities with the methodological instrument with which philologists critically edit texts and manuscripts. in the first part, we present a survey of the primary film and non-film sources collected for the purpose of the reconstruction and restoration process which are also at the basis of the digital critical apparatus and their examinatio; in the second part, we focus on the actual restoration and reconstruction methodologies, practices and issues we are working on at the present moment while making a morphological and qualitative evaluation and discussing some of the interesting loci critici we have found during the process. in conclusion, we hypothesize the creation of a single object that contains the restored edition plus documentation that puts the apparatus on view, in a very raw concept of the digital environment under construction. 3. method our theorical background is based on a long film restoration tradition (canosa, farinelli, mazzanti, 1997) with a philological approach deriving from the philology of printed texts, mainly focused on the analytical description of a book’s physical characteristics and modes of production (tanselle, 2020). our methodological work involves disciplinary areas sharing common attention towards material culture and the relationship and inextricable links between formal and material artefacts (fossati, 2018) that inspired the well-known historical evidential paradigm framed by ginzburg (ginzburg, 1986) and the pioneering application of this paradigm to film inspection by “excavator” harold brown (brown and boltwellens, 2020). furthermore, an effort to frame the relationship between formal and material artefacts was made recently in digital media studies in the shape of the forensic approach proposed by kirschenbaum (kirschenbaum, 2008). in this perspective, to apply the philological method, the first step is to collect all the survived witnesses, and then to gain an adequate familiarity with them (macé, 2015), that is the recensio. the next one is to describe and analyze them (that is the examinatio) and then to compare the texts they contain (lectio): this process is called collatio (macé, 2015). the next and last phase is the textual reconstruction, made by editing and combining shots and sequences from different witnesses, according to the version chosen (in our case, the 1918 italian version). the following paragraphs therefore describe the reconstruction process, according to the methodological steps just summarised. recensio. table 1 sums up all the film elements found during the initial survey, carried out among several film archives, museum, and collections. witness “k” from associazione kinoatelje is a 35mm nitrate print on three reels, which is approximately 900 m long; it witnesses the 1918 italian version and is the main reference for our reconstruction since it is a first-generation print, as attested by the edge codes and other clues; in addition, it includes handwritten information on the film edge about the colour palette. it retains most of the narrative order, the original italian intertitles and the tinting and toning colours. digital struggles for film restoration: la battaglia dall’astico al piave 57 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140107 tab. 1. report of the witnesses collected after the film archive survey. witness “g” from cineteca del friuli, in gemona, is a 35mm nitrate print further subdivided into three witnesses. “g1” and “g2” are two tinted and toned reels, respectively 290 and 230 metres in length, that witness the 1918 french version, whose first public screening in paris is known to date from 7 august 1918 [2]; witness “g3” is a short fragment of the italian version, found within the film da capodistria a fiume italiana. during the 1990s, cineteca del friuli and lobster film duplicated and restored the film materials from 1918 (g1, g2 and g3) at the haghe film lab in amsterdam. presently, the restored 35mm copies from the nitrate prints are preserved by cineteca del friuli, which houses the preservation master on acetate and the restored print on polyester, while the original nitrate copies are “missing in action”, in other words, lost in some nitrate vaults in paris. witness “rm” from istituto luce in rome is a 35mm duplicate negative and positive on safety stock, consisting of four approximately 1000 m-long reels, with flash intertitles; the black-and-white image contents and intertitles probably witness the 1927 re-edition of the 1918 version, preserving large segments which are missing in “k” and “g”. unfortunately, the materials from the 1910s– 20s are no longer preserved at the istituto luce in rome. witness “mi” from cineteca italiana in milan is a 35mm positive fragment on nitrate film consisting of two reels. it is close to the 1927 luce edition, as attested by the intertitles and the insertion of later documentary materials. witnessing the 1927 version, it was recently duplicated by l’immagine ritrovata. witness “to” dio segnò i confini d’italia, became part of the collection of the museo nazionale del cinema in turin during the 1960s but no information relating to the donor or seller is known. it retains just a few scenes of la battaglia dall’astico al piave, but it is important because it gives us a missing intertitle with the relative scene of the 1918 italian version. it was about 540m long and printed on negative film from which the museum printed a positive on triacetate film. in 2015 the museum decided to make a 2k digital scan of the ctn. unfortunately, all the original information has been lost. we made further comparisons with other films from the end of the 1920s onwards, such as resistere (1918), the other army (1917), il piave mormorò (1934), guerra nostra (1928), gloria – la grande guerra (1934), and, like witness “to” described above, we found them to contain minor parts of la battaglia, identifying relationships and contaminations between several films from the period. we carried out the recensio on film as well as photographic and private archives, journals and so on. indeed, the survey of non-film materials should not just be considered ancillary or secondary work to support, validate and aid the restoration and reconstruction tasks. instead, it is a core activity central to placing the film artefacts (both in conceptual and material terms) in an intermedial and cultural chain and network. in other words, witness title version format element support reels length colour k associazione kinoatelje) [la battaglia dall’astico al piave] it (1918) 35mm positive nitrate 3 913 m tinted and toned g1 – g2 (cineteca del friuli/lobster films) la bataille sur le piave fr (1918) 35mm positive dupe neg dupe pos nitrate acetate polyester 2 521 m tinted and toned g3 (cineteca del friuli/lobster films) da capodistria a fiume italiana it (1918) 35mm positive dupe neg dupe pos nitrate acetate polyester 1 336 m tinted and toned bw rm (istituto luce) [la battaglia dall'astico al piave ta pum] it (1927) 35mm dupe neg dupe pos safety 4 1073 m bw mi (cineteca italiana) la battaglia dall'astico al piave it [1927] 35mm positive nitrate 2 [402 m] tinted to (museo nazionale del cinema) dio segnò i confini d’italia it (1918) 35mm ctn positive acetate 1 540 m bw digital struggles for film restoration: la battaglia dall’astico al piave 58 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140107 it frames our research objects as contemporaneously archival, archaeological and historical artefacts within an entangled approach to preservation and restoration. our primary sources included the gazzetta ufficiale del regno d’italia, whose reviews attest a first screening of the french version of la bataille sur le piave in paris on 7 august 1918. others are the many newspapers that demonstrate the continued circulation of the film, probably in the luce re-edited version, with the name la battaglia dall’astico al piave, till 1933 [3]. as seen, these findings prompt many doubts even about title of the film itself. furthermore, we identified many primary sources such as texts and volumes of the time, diaries of the men who experienced these events, military reports, photographs, periodicals, etc. and matched them with the photographic documents produced in the same period as the film and the information about the activity of the film department [4] of the italian royal army to establish precise correlations between the filmed sequences. this allowed us to reconstruct the days of the second battle of the piave and to date and locate most of the sequences in the film. the intersection of images and related captions circulating in the press of the time, such as l'illustrazione italiana and la guerra series, both published by fratelli treves, enabled us to identify not just the same moments in the war operations and the same places of the battle, but also the key characters of the events, shown from different and complementary angles. furthermore, the cover page of la guerra special issue resembles the title blocks and the intertitles of the film. this comparison work also helped us exclude from the collation some passages of film footage present in the “rm” or “mi” witnesses but not consistent with the first italian edition. fundamental support for the research was given by consulting diaries and sources in museums [5], most of which are accessible through the european film gateway (efg). for example, we consulted the diaries of major maurizio rava [6], preserved in the museo del risorgimento in milan, in which he transcribed important takes from the film. equally as important in this research phase was the knowledge of some experts of the historical period under investigation [7], which helped us identify, localize and date some sequences, over which there were still some doubts. this enabled us to decide whether to include those parts in our final reconstruction or not. examination and collatio. when a large number of witnesses are collected, such as in our case, each one of them requires comprehensive and meticulous study in order to highlight the innovations transmitted by two or more of them (and conversely to isolate deviations in the single versions), variants and errors (generally called loci critici) in order to identify and reconstruct the restitutio textus. the restorer must look at the material and production methods, tinting and toning, splicing techniques, etc. to make choices consciously and with a “critical eye”, like in an excavation (carandini, 2000). in other words, a direct and instrumental diagnostic investigation of the artefact has to be made (venturini, 2007b). the descriptiveanalytical study of the physical characteristics of films has a long history, which partly derives from the pioneering application of the so-called evidential paradigm by “excavator” harold brown (brown, 2020). a particularly important step in our workflow was the production of apparatus documenting the witnesses using a descriptive and morphological approach to the material artefacts, in order to produce both isomorphic and non-isomorphic descriptions. the isomorphic descriptions consist of visualizing the artefact with different instruments. while the habit of using digital interfaces and “surrogates” progressively reduces opportunities to actually touch the physical artefacts, our field deals with this issue as the very latest in the long history of the mediation and representation of artefacts. indeed, the historiography of material culture has learned how to operate from disciplines such as palaeontology and archaeology, which abound "not only in artefacts from the past, but also in ways to document and study them [...] visual media are indispensable in the process of documentation, that is, the practice of transforming things from the past into manageable and malleable forms" (olsen et al., 2012). three different ways of documenting “things from the past”, such as film artefacts, supported our work: screeners, edge-to-edge scanning and “repro-set” shootings. screeners, to quote again from the archaeological field, are “proxies of our vision of the past” (olsen et al., 2012) which allow historical practice, and especially practice on material culture and physical artefacts acting as intermediates, to come closer, as proxies [8], to us (figure 1). the proxies of each witness indicate the frame number, which has been added to simplify identification and identify each one for the following documentation activities. this kind of visualization facilitates comparisons between the witnesses, even when they are not physically in the lab, as well as the non-isomorphic description as we will see below. furthermore, we must consider that our screeners come from dpx sequences originating from different digital sources (such as from different film scanners, digital routes and laboratories) and that the witnesses were printed through different photochemical routes and laboratories. digital struggles for film restoration: la battaglia dall’astico al piave 59 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140107 fig. 1. example of a proxy file taken from the reel 2 of witness "k" on which we have added the frame reference number (1453) to make it univocal. edge-to-edge visualization, practised in udine since the early 2000s, could be framed as a mode of visualization grounded on the philological tradition and an equivalent to the so-called “mechanical” or “photographic” edition of a manuscript or a book (venturini, 2007a). edge-to-edge scanning is “digital representation of the complete film strip as opposed to the sequence of frames provided by conventional film scanners (which ignore the rest of the film strip area)” (gschwind, 2002). it allows archivists, restorers and scholars to observe and analyse various pieces of information, such as the edge codes or other handwritten annotations. for our study, it was particularly useful for those witnesses (“rm” and “mi”) that we were not allowed to observe directly but we needed to analyse for the reconstruction choices (figure 2). fig. 2. example of an edge-to-edge taken from reel 1 of witness "rm" (frame 3093); even if it is a negative copy, it is possible to identify the overlapping of the positive perforations; it shows the producers' edge marks “agfa” on the left and the numbers “509” that are a part of the edge code, on the right. moreover, edge-to-edge representation and visualization relate a different media history, which is what we are looking for. “repro-set” photographic documentation could be seen as a first and consolidated example of a diagnostic approach, originating from those used in the fields of traditional cultural heritage. it is an adaptation of the set-up proposed by barbara flueckiger to obtain diagnostic documentation using the photographic technique. to date, we have produced documentation of the practices leading to the current morphology of witness “k” by taking pictures of all the useful evidence, such as splices, colour indications on the film edges and the brand of the film manufacturer, which will help us with the textual and visual reconstruction. furthermore, this kind of documentation of the damage, errors or defects occurring in the copy will help us to distinguish them in the digital restoration phase (figure 3). for witness “g”, the “repro-set” documentation was created with the sole purpose of mapping the colours reproduced on the copy through the desmet process. this will be used as a reference for the reproduction of the tinting and toning colours in the reconstructed version. all the files produced have been made for different purposes and helped us with the non-isomorphic description. fig. 3. example of a “repro-set” documentation with the handwritten indication for the tinting color to print “60 giallo” and the identification code of the film “s–o– 155”. it is also possible to see the edge code kodak ▪ that allows to date the film strip to 1917. picture taken at la camera ottica lab of the university of udine. non-isomorphic documentation is the description of the artefact through découpage and annotations. in a genealogical and archaeological perspective, before being thought of as equivalent to a present-day metadata recording and digital annotations, the non-isomorphic description is based on ancient layering tools such as socalled découpage. on one hand, this is a prismatic digital struggles for film restoration: la battaglia dall’astico al piave 60 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140107 theoretical concept, as recently re-framed by film scholars such as kessler, barnard and le forestier, which has grown up since the outset of classical european film theory (le forestier, barnard and kessler, 2020). in this meaning, découpage is seen as an anatomical and entomological approach to the formal and material artefact that can be used in order to dissect it. on the other hand, a second and specific meaning of découpage, which has played a particular role and function since the time of the inception of film culture in the 1920s and 30s, is the sceneggiatura desunta (usually translated in english as “technical screenplay”), a framework for understanding a film as a whole, both as a formal and conceptual structure and as a more concrete architectural artefact (may, 1939). more specifically for our interests, it is philological and archival attention to historical artefacts in an age of scarce study resources. in this perspective, to apply the philological method in order to critically frame the film tradition is to dissect and examine film as an organic and formal structure. far from being a mere tool for textual analysis, the non-isomorphic description aims to document a material and editorial layout and at the same time lays the foundations for its reconstruction and transmission. in practice, we created a first non-isomorphic description in excel files in which we describe, annotate and report several pieces of information. by keeping the physical editing with the handwritten annotations on the borders as a reference, we transcribed the numbers of the scene/intertitle and its colour indications, the references to the first and the last frames in the proxy files (and the count of the frames) and/or the visual recordings produced through the “repro-set” documentation devices. 4. results we meticulously analysed all the witnesses, each of which retains its own specific material and cultural history. we deemed it very useful to subdivide the alterations into damage, errors and defects in order to create a series of rules of engagement for the subsequent restoration operations: both damage and errors can be amended because they are part of the later history of the film artefact; defects must be preserved since they are part of the original (brandi’s “duration”) and they describe how technical limits and/or specific non-normative practices can shape the film right from the start (canosa, 2001). textual reconstruction. after the découpage of each witness, the non-isomorphic collation and annotation were reported in an excel file. we then based the reconstruction on the numbering of the scenes. this was done in an isomorphic way through non-linear multitrack editing programs and with multiscreen displays on davinci resolve (blackmagic) to compare all the witnesses with each other and identify the best element for our reconstruction. in this phase, we recognized variants and errors (loci critici) which needed to be resolved by applying mechanical law or conjecture (iudicium or emendatio ope ingenii). witness “k” turned out to be the best first-generation element for the reconstruction of the 1918 italian version. if we found shots and sequences in several witnesses or if the images were too degraded to be clear and usable (the end of reel 2 of “k” suffers from gelatine and base decomposition), editorial choices were made by weighing up the quality of the image and the completeness of the scene, comparing the number of frames and preferring “g” for its temporal proximity to the reference witness and for the considerably higher image quality. when the scenes of “k” were shorter, but the sense was not lost, we always preferred a higher image quality and did not insert the few missing frames from other witnesses. in part, after a careful comparison of every witness, the missing sequences were found in “rm” and “g”. from witness “mi”, however, we chose the final sequence of the film since it is longer than the others and qualitatively better. very recently, we finally found what we believe to be the lost scene corresponding to intertitle 26 in witness “to” [9]. in addition, we are working on the comparison and inspection of twelve dvds found in the george eastman house collection preserved by the library of congress and on a nitrate negative fragment very recently discovered at the cineteca nazionale in rome, which, among other different materials, preserves a few missing shots, including the fourth italian intertitle [10]. as regards the intertitles, we decided to maintain the original ones from the italian 1918 version as surviving in “k”. they display the code “r37” in the bottomright corner to identify the film, which is the same for the italian and the french version (in which an “f” has been added for french); in the bottom-left corner, it is possible to see the number of the intertitle, which helped us to find them in other films too, as was the case for intertitle 26, recently found in the film dio segnò i confini d’italia preserved by the museo nazionale del cinema in turin, which allowed us to add the corresponding sequence. where missing in “k” but found in “g”, we did not opt for a digital simulation and reconstruction of the title block, font and structure, but decided to report only the text and the numbers of the intertitle and the film on a neutral background, with the texts in square brackets. for the translations from the french, as a reference we took the intertitles found in the 1927 italian version (witness “rm”) or non-filmic documentation such as the captions of the digital struggles for film restoration: la battaglia dall’astico al piave 61 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140107 photographs produced at the same time by the film department of the italian royal army, censorship approval, the intertitles list, and so on. we made the same decision to keep them as neutral and identifiable as possible within the filmic text for the intertitles attributed to the film found in witness “rm”. one of the loci critici we discussed during the reconstruction phase is the first four missing italian intertitles. we found them in the french 1918 version, but they are the other way round and they do not fit with the italian 1927 version (figure 4). fig. 4. the four intertitles from the french 1918 version follow an unruly order but they are the only existing proof of the first intertitle. the number in the bottom-right corner identifies the film (r37, the same number for the italian and the french version) and the version information (f, for french) while in the bottom-left corner it is possible to see the number of the intertitle: 3-2-4-1. in order to reconstruct them, we had to rework the witness and ask many questions about how to deal with them since we do not have documentation supporting the choice to change the order. we should suppose it is due to the different importance of the italian monarchy in france, which made the film information (title and director) more important, while in italy the presence of the portrait of the king and other generals of the royal army forced the audiences to stand up and pay tribute. furthermore, the fourth intertitle identifies the “premiere partie” of the film, but during the film there are no other indications about where it ends or the overall number of parts in witness “k” or “g”; only in witness “rm” is the third part indicated, but we are not sure whether it should be taken it into account since it is a later and very contaminated version. lastly, we created a timeline including all the scenes and intertitles and, at the moment, we are working on restoring them through the digital intermediate route. then, we will record it back on film to reproduce the tinting and toning through the desmet method and scan the 35mm colour print for conformity at least between the photochemical and digital theatrical copies, which could not be achieved otherwise. however, we will produce a first release in dcp, applying the desmet digital process for the reproduction of the 1918 tinting and toning palette, using the handwritten annotation on the edge of witness “k” as a reference since these notes come from the original camera negative. here is another of the loci critici: in several cases, the indication does not correspond with the real colour in the surviving print, or the shades are different when the same colour is indicated (figure 5). fig. 5. even though the indicated color is the same and the shots are in succession, they appear in two different colors. above: shot n. 100 – green tinting (from witness k – reel 2 – frames 7931-7934) with the handwritten indication “100 – i – verde”; below: shot n. 101 – green tinting (from witness k – reel 2 – frames 7949-7952) with the handwritten indication “101 – i – verde” digital struggles for film restoration: la battaglia dall’astico al piave 62 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140107 we will have to discuss which shade to take as reference for the reconstruction and we will probably use the shots made with the “repro-set” documentation as a reference. furthermore, we will screen the italian (“k”) and the french (“g”) 1918 versions and make a comparison between the colouration of each scene, and we will discuss which colours to attribute to the “rm” scenes, since they are from a black-and-white negative duplication. 5. conclusions at present, the reconstruction covers more than 90% of the film (more than 1170 metres out of the 1255 metres recorded by the censorship visa), which is an exceptional result that can indirectly resolve and clarify the relationships and contaminations between several films and documents from the period. in conclusion, as is more and more easy to understand, despite having chosen the 1918 italian version as a reference, our aim is not strictly focused on the canonical reconstruction and restoration of this single chosen version. rather our aim is to give an account of the restoration process of the final product and of the many different practices that shaped the multiple originals, the many relationships among the sources, the different genealogies, as well as the accidents, contaminations and finally the archival status and provenance of the film materials. hence, we intend to build up a web-based historical-critical digital environment for the films and to document the film restoration process. in this environment, it will be possible to see the restored film like a normal cinemagoer, but, according to the audience’s interests, it will also be possible to watch the original materials, analyse the variants and see the analogies or differences among them, while explaining the loci critici; to see the restoration interventions and make beforeand-after comparisons; and also to see both the edgeto-edge and the “repro-set” documentation, and, obviously, all the non-filmic sources on which our reconstruction is based. 6. conflict of interest declaration the authors of this paper state that there are no conflict of interest including financial, personal, or other relationships with other people or organizations within three years of beginning the submitted work that could inappropriately influence, or be perceived to influence, their work. 7. funding source declaration the restoration and the related research have been supported by direzione generale archeologia belle arti e paesaggio – ministero della cultura (mic). 8. acknowledgment our reconstruction and restoration work is carried out by a wider technical and research group within the department of humanities and cultural heritage of the university of udine. the team consists of the two authors, restorer daniela pera, technicians gianandrea sasso and giacomo vidoni, and digital restoration assistants anna donati and petra marlazzi. we also would like to thank both mariapia comand and cosetta saba for their support and for giving us the opportunity to carry out the project. this work would not have been possible without the aid of the associazione kinoatelje, la cineteca del friuli, lobster films, istituto luce, cineteca italiana, museo nazionale del cinema and l’immagine ritrovata. we would like to thank for their essential help for the reconstruction elena beltrami, serge bromberg, patrizia cacciani, roberto della torre, aleš doktorič, alessandro faccioli, claudia gianetto, martina humar, livio jacob, fabrizio micarelli, alessia navantieri, elena nepoti, matteo pavesi, gabriele perrone, sarah pesenti campagnoni, davide pozzi, andrea tessitore and camillo zadra. 9. short biography of the authors serena bellotti is a phd student in history of art, cinema, audiovisual media and music at the university of udine. she is working at the restoration of la battaglia dall'astico al piave (1918), carried out by university of udine and at the restoration project of spedizione franchetti in dancalia (1929) in collaboration with istituto luce. simone venturini is professor at the university of udine and one of the founders of la camera ottica lab. he is the scientific coordinator of the filmforum and director of udine’s imacs. his research interests include history and theory of film archives, film restoration, media archaeology and production studies. he published in springer, berghahn, aup, carocci, marsilio, and journals such as jfp, cinéma&cie, and bianco e nero. digital struggles for film restoration: la battaglia dall’astico al piave 63 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140107 notes [1] film title: battaglia dall'astico al piave (la). produced and distributed by the film department of the italian royal army. metres: 1255; censor visas: 13649; requested on 5 november 1917; approved on 11 july 1918: http://www.italiataglia.it/search/opera (last accessed: 5 july 2021). [2] gazzetta ufficiale del regno d’italia, 8 august 1918. [3] “kinema”, june 1930; “il mattino illustrato”, 9–16 june 1930 (23); poster announcing the projection of the film la battaglia dall'astico al piave 1915-1918 in the teatro civico in la spezia, 1933 (preserved by museo centrale del risorgimento, id. code: simp_071). [4] the film department consisted of both the photographic and the cinematographic sections. they shared vehicles, equipment and shot several of the same contexts and events from similar points of view. [5] museo della battaglia in vittorio veneto; museo storico italiano della guerra in rovereto and museo centrale del risorgimento in rome. [6] starting in january 1917, and for remainder of the first world war, he directed the army cinematographic section of the press office of the supreme command (rome, archive of the historical office of the army general staff, f1, cs, uv, b. 299, note 15 may 1917) [7] we have talked to camillo zadra, director of the italian war history museum in rovereto, the "battaglia del solstizio" historical cultural association, elena nepoti (imperial war museum) and alessandro faccioli (university of padua). [8] in computer science, a proxy is an intermediary machine, while in digital post-production, a proxy is a “duplicate file of a project’s source footage, a transcoded file that’s smaller in file size and at a lower bitrate than the original”. etymologically, the concept of proxy is related to “procuracy”, from the latin procuratio “caring for, management”, and procurare “to manage”, in short, the agency of “one who acts instead of another”. lastly, proxy also recalls an idea of proximity, due to the etymology of “proximus”, wherein the idea of “nearness” and “vicinity” does not so much recall what is near in terms of closeness to the origins but instead close to us: the "latest, the most recent; the next, the following”. [9] this evidence came from our talk with alessandro faccioli (university of padua), whom we would like to thank. [10] we want to thank the president of the cineteca del friuli, livio jacob, for his advice about the library of congress materials and alberto anile, sergio bruno, valentina rossetto and maria assunta pimpinelli for their help about the material preserved at cineteca nazionale. references brandi, c. (1977) teoria del restauro. torino: einaudi. brown, h. and bolt-wellens, c. (2020) physical characteristics of early films as aids to identification. bruxelles: fédération internationale des archives du film. canosa, m. (2001) "per una teoria del restauro cinematografico", in brunetta, g. storia del cinema mondiale. teorie, strumenti, memorie. torino: einaudi. canosa, m., farinelli, g. and mazzanti, n. (1997) "nero su bianco. note sul restauro cinematografico: la documentazione", cinegrafie, (10). carandini, a. (2010) storie della terra. torino: einaudi. chiesa, p. 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(2007) le spoglie del serpente. storia e teoria del restauro cinematografico: dal restauro all’edizione critica del film. phd. università degli studi di udine. 48 color culture and science journal vol. 12 (1) doi: 10.23738/ccsj.120106 an educational experience about color emotion and its design implications cristina boeri1 1 color lab, department of design, politecnico di milano. cristina.boeri@polimi.it corresponding author: cristina boeri (cristina.boeri@polimi.it) abstract the paper presents the context, contents and results of an educational experience conducted within the shapes, surfaces and colours module of the master in furniture design by poli.design, politecnico di milano, in december 2018. this experience is part of a color design education research project with the aim to explore, evaluate, experiment and systematize design implications offered by the evaluation of the emotional response to color in design education and professional practice. besides the educational purposes, this experience allowed us to verify, evaluate and compare the presence of associative recurrences between a selection of emotion words and color attributes, firstly with an initial exploration without using color samples, and secondly with the construction of contextualized 4-color combinations. finally, in a process of student-learning and experimentation that moves from abstraction and generalization towards design contextualization, the possibility of using such experiences and connotative associations to build the emotional character of an interior space was explored. the results of this experience contribute to validating the design opportunities offered by the possibility of dealing with the evaluation of the emotional response to color in terms of color attributes, and thus of color combinations. in addition, the use of such associative assumptions to build the emotional character of an interior space seemed to be a useful educational and methodological tool to relate color to the other design components—shape, material and surface, in particular—and to show the potential value of a design process structured around color and the sensorial and emotional qualities of the environment. keywords color design education, color emotion, color association, color combination received 16 october 2019; revised 28 november 2019; accepted 15 december 2019 an educational experience about color emotion and its design implications 49 color culture and science journal vol. 12 (1) doi: 10.23738/ccsj.120106 1. introduction the evaluation of the emotional response to color, or ‘color emotion’, concerns both the aesthetic experience of color and the connotative experience of color in relation to concepts such as warm or cool, light or dark, heavy or light (sivik 1970, gao and xin 2006). as lars sivik (1970:43, 1989:132) points out, the prerequisite for this type of studies lays in the fact that people prove to be sufficiently concordant in their connotative experiences and opinions about color. as ou et al. (2004a:232) observe, early studies on singlecolor emotion were concerned with the possibilities of reducing a large number of color-emotion scales into a smaller number of categories, or factors, by using the semantic differential method introduced by osgood et al. (1957). these studies also revealed connections between these factors and the three color attributes, generally defined as hue, brightness or lightness for object colors, and chroma or saturation (wright 1962) [1]. as noted by küller (1981:162) regarding this area of research and compared to the numerous studies conducted on single-color-without-context, only few studies were concerned with color combinations. among the studies focused on the implications of using not just single colors but combinations of two or more colors, sivik and hård (1989) investigated how different dimensions of meaning can show varying degrees of relationships with different kinds of 4-color combinations. kobayashi (1991) proposed a systematic classification of color combinations using 130 basic colors to create different 3-color combinations and 180 matching image words. ou et al. (2004a, 2004b) conducted a study on both single colors and 2-color combinations in relation to those color-emotion scales that were most used in previous studies. within this framework, the educational experience carried out within the shapes, surfaces and colours module of the master in furniture design by poli.design, politecnico di milano, enabled students to experiment and evaluate the design implications related to the emotional response to color in terms of 4-color combinations, and provided the possibility of using such experiences and connotative associations to conceptualize the emotional character of an interior space. this experience is part of a color design education research project with the aim to explore, evaluate, experiment and systematize the design implications offered by the evaluation of the emotional response to color in design education and professional practice. the research project is focused on the possible relationships between the approaches, methods and outcomes of color research that deals with color emotion and the approaches, methods and tools developed in the field of design research and practice that deals with color and the emotional and sensorial qualities. in this regard, note the methods and tools developed in the field of cmf design (colors, materials, finishes) and qualistic by clino trini castelli (castelli 1995, 1999) and the color image scale by shigenobu kobayashi (kobayashi 1991). the research outcomes may highlight aspects of development in the area of color research oriented to possible design applications in terms of the contextualization and usability of the research results. the educational experience presented here follows the results of a previous didactic experimentation (boeri 2019) that allowed exploring and evaluating the possibility of establishing associative recurrences between a selection of ‘evocative terms’ and 4-color combinations developed by the students drawing from an almost unlimited number of color samples. numerous studies on single color emotion (ou et al. 2004a, gao and xin 2006, da pos and valenti 2007), color pairs (ou et al. 2004b) or 4-color combinations (sivik and hård 1989) are based on a predefined number of color samples. in the experimentation presented in this paper students were first asked to establish associations between a selection of connotative terms, in the form of pairs of opposites, and color attributes in absence of color samples, and then to establish associations between one or two of the connotative terms selected and 4-color combinations drawing from the 1,950 standard colors of the ncs system, which leads to an even higher number of color combination possibilities (sivik and hård 1989). in a process of learning and experimentation that moves from abstraction and generalization towards design contextualization, the possibility of using such experiences and connotative associations to build the emotional character of an interior space was explored. this contribution presents the contents and methods of this teaching experience and the student-learning results in order to evaluate the associative recurrences and relevancies between the selected terms and the color attributes. 2. contents and method the teaching experience planned within the shapes, surfaces and colours module of the 1st level specializing master in furniture design, learning from the italian experience, by poli.design, politecnico di milano, was conducted by the author in december 2018, over a period an educational experience about color emotion and its design implications 50 color culture and science journal vol. 12 (1) doi: 10.23738/ccsj.120106 of 3 days and covering a total of 21 hours. the color course was organized to offer students theoretical contents on color and practical color design implications. following a teaching method that had already previously been partially tested (boeri 2019), twenty-four students from different nationalities were asked to proceed in two phases. the first phase was configured to allow students to explore and experiment with the design implications of the 4-color combinations associated with a selection of connotative terms, or ‘color emotion words’ (nakamura et al. 2005), chosen on the basis of their recurrence in the literature addressing the emotional response to color, or color emotion, (ou et al. 2004a:233), and their relevance to possible design developments [2]. the terms selected in the form of pairs of opposites were: classic–modern, cool–warm, dynamic–quiet, hard–soft, and heavy–light. the second phase was conceived to experiment and evaluate the possibility of applying the associations and 4color combinations previously developed to build the emotional character of an interior space. the two phases were developed following a process of student-learning and exploration that moves from a rather abstract and general content towards a specific contextualization in a student’s design project (fig. 1). in summary, the students were first asked to place each of the proposed emotion words within an organized map with a vertical axis of lightness and a horizontal axis of saturation forming four quadrants. each axis is further subdivided into 10 equal steps, with 0 at the intersection of the axes and increasing to 10 at the periphery. additionally, the two quadrants to the left are characterized by the association cool and the two quadrants to the right with the association warm. the association with cool and warm is taken as an indicator of an evaluation concerning also the hue attribute (fig. 2). fig. 1. on the horizontal rows are shown three students’ work, produced in the course’s 1st phase (two plates left) and 2nd phase (two plates right) of the shapes, surfaces and colours module (professor: c. boeri) of the master in furniture design, poli.design, politecnico di milano (director of the master’s course: a. deserti; co-director: f. zurlo). students: francesco mercuri, devanshi doshi, pier paolo perrotta. an educational experience about color emotion and its design implications 51 color culture and science journal vol. 12 (1) doi: 10.23738/ccsj.120106 the visual organization and the terminology represented in the map of color attributes is designed to help students complete the required task. it takes into consideration that this may be the students’ first exposure to color attributes and associations. the map and the emotion words were explained to the students in advance. this task had a dual purpose: on the one hand, to invite students to explore all the proposed words before proceeding to the choice of the ones they wanted to develop; and, on the other hand, to evaluate the possibilities of establishing associations between emotion words and color attributes in the absence of color samples. fig. 2. the map provided to the students to explore and evaluate the associations that can be established between the selected word pairs and the color attributes. at the intersection of the axes there is a medium gray (= 0), at the ends of the axes the maximum lightness, darkness or saturation (= 10). subsequently, the students were asked to freely choose one or two emotion words from those proposed and then build 4-color palettes associated with each word using the visual selection from the ncs 1,950 standard color samples and the ncs navigator. the pre-set plate supplied to the students envisaged that for each palette there would also be some evocative images useful to contextualize the palette in relation to the sought after association, the visual hierarchies that each color can take inside the palette and the characteristics of each color and color combination with respect to the color attributes using the ncs color circle and ncs triangle (fig. 3 a, b). fig. 3 a, b. two examples of students’ 4-color palettes associated with the word ‘cool’. students: natalia arkharova, firas abu dahab. in a second phase the students were asked to apply the associations they found between the emotion words and the palettes previously developed to build the emotional character of an interior space. in summary, the students were asked to develop two mood-boards able to describe and synthesize through images the emotional and sensory characteristics of an interior space, referring to the domestic or retail environment, using as main reference the emotion word and the relative color palette already developed, and declined according to a further connotation to choose from within a new selection of the proposed word pairs: casual–elegant, playful–serious, simple–sophisticated. divided into two plates, the task initially involved the construction of a mood-board aimed at creating a strongly evocative ‘character’ of an interior environment related to the selected emotion words, and subsequently at conceiving an inspirational materialchromatic scenario (fig. 1, two plates right). the students’ works were analysed in part during the course to provide a basis for verification, comparison and an educational experience about color emotion and its design implications 52 color culture and science journal vol. 12 (1) doi: 10.23738/ccsj.120106 shared discussion with respect to the results produced, and in part in retrospect, to verify, evaluate and compare the presence of associative recurrences between emotion words and color attributes both with respect to the initial exploration, without color samples, and to the colors and organisational schemes used for the construction of the 4color combinations. 3. results and discussion the initial map results, in relation to a total number of 17 works submitted, were visually rearranged to show the presence of possible associative recurrences in relation to the lightness and saturation attributes and the cool–warm polarity, for each emotion word (fig. 4). fig. 4. the maps with the results from 17 works submitted were visually rearranged to show the presence of possible recurrences in relation to the attributes of lightness and saturation and to the cool and warm connotations for each word. one submission was incomplete in that it did not include ‘quiet’ and ‘heavy’. an educational experience about color emotion and its design implications 53 color culture and science journal vol. 12 (1) doi: 10.23738/ccsj.120106 the results show for the classic–modern polarity a concentration of associative evaluations in relation to the cool–warm polarity, with (1) classic that presents a greater concentration of evaluations in the quadrants connoted with warm (fig 2, right half of the map) and (2) modern in those connoted with cool (fig. 2, left half of the map), and, for modern also appears a concentration of evaluations in relation to the quadrants connoted with light (fig. 2, upper half of the map ranging from 0 = medium gray to 10 = maximum lightness). the cool–warm polarity (in addition to the obvious correspondence with the cool and warm halfs) shows on the map a concentration of associative evaluations related to the lightness attribute with (3) cool that presents a greater concentration of evaluations in the quadrant connoted with light and cool and (4) warm in the quadrant connoted with dark and warm. the dynamic– quiet polarity shows a concentration of associative evaluations in relation mainly to the saturation attribute, with (5) dynamic that presents a greater concentration of evaluations in the saturated areas (5–10) and (6) quiet that presents an even more evident concentration of evaluations in the desaturated areas (0–5). the hard–soft and heavy–light polarities show a concentration of associative evaluations mainly in relation to the lightness attribute, with (8) soft and (10) light that present greater concentrations of evaluations in the quadrants connoted with light, and (7) hard and (9) heavy in those connoted with dark (fig. 2, lower half of the map ranging from 0 = medium gray to 10 = maximum darkness). in addition, (10) light presents a greater concentration of evaluations on the vertical gray axis and in the lightness areas (6–10) and is related to the cool connotation compared to (8) soft that presents a greater distribution on the upper half of the map. the results of the analysis of the colors and organisational schemes used for the construction of the 4-color palettes, carried out in retrospect on a total number of 37 works, were visually synthesized using the ncs triangle and ncs circle to show the presence of possible recurrences and their relevance in terms of hue and/or nuance (fig. 5). taking into account the number of works that could be analysed for emotion words, the most relevant results show: for (1) classic a recurrence of color combination schemes based on hue analogies and a concentration of the mostly used hues in an area of the circle between y and r20b; for (3) cool a recurrence of color combination schemes based on hue analogies and a concentration of the mostly used hues in an area of the circle between r90b and b20g; for (5) dynamic a recurrence of color combination schemes based on the differentiation of hues (at least 2 hues) and a concentration of the mostly used hues in three areas of the circle, between y and y30r, between y90r and r10b, and between r70b and b; for (6) quiet a recurrence of color combination schemes based on nuance analogies and a concentration of the mostly used nuances in an area of the triangle with blackness between 05 and 20 and chromaticness between 0 and 30; for (8) soft a recurrence of color combination schemes based on nuance analogies and also on hue analogies with at least two hues identical or closely located on the circle, and a concentration of the mostly used nuances in an area of the triangle with blackness between 05 and 30 and chromaticness between 0 and 30; for (9) heavy a recurrence of color combination schemes based on nuance analogies and a concentration of the mostly used nuances in an area of the triangle with blackness between 40 and 90 and chromaticness between 0 and 40; for (10) light a recurrence of color combination schemes based on nuance analogies and hue analogies and a concentration of the used nuances in an area of the triangle with blackness between 05 and 30 and chromaticness between 0 and 30; for (2) modern any recurrence in the color combination schemes appears; for (4) warm and (7) hard the colors and organizational schemes that can be analyzed refer to single works; and, for (4) warm a color combination scheme based on the same hue y and for (7) hard a color combination scheme based on the analogy of 3 nuances characterized by blackness between 60 and 90. the comparison of the results of the analysis of the colors and organisational schemes used for the construction of the 4-color palettes (fig. 3 a, b) with the results of the initial exploration inserted on the maps (fig. 4) allows us to observe and evaluate the presence of possible coherences with the associative evaluations emerged between emotion words and color attributes. in particular, the development of the 4-color palettes associated with the classic–modern polarity shows a coherence with the associative evaluation mainly in connection to cool and warm limited to the emotion word (1) classic and with reference to the hue attribute with a concentration of the mostly used hues in one area of the circle, between y and r20b that correspond to the so-called ‘warm hues’ (wright 1962, da pos and valenti 2007). as well, the development of the 4-color palettes associated with the emotion word (3) cool shows an associative evaluation in connection to the hue attribute with a concentration of the mostly used hues in an area of the circle, between r90b and b20g that correspond to the so-called ‘cold hues’ (wright 1962, da pos and valenti 2007). the development of the 4-color palettes associated with the dynamic–quiet polarity shows a coherence with the associative evaluation mainly in connection to the saturation attribute especially for the emotion word (6) quiet. the development of the 4-color palettes associated with the hard-soft and heavy–light polarities show coherences with the associative evaluations mainly in connection to the lightness attribute. an educational experience about color emotion and its design implications 54 color culture and science journal vol. 12 (1) doi: 10.23738/ccsj.120106 fig. 5. the results of the analysis of the colors and the patterns used for the construction of the 4-color combinations associated with the selected emotion words, conducted on a total number of 37 works, were visually synthesized using the ncs triangle and ncs circle. the 4-color combinations associated with each emotion word can be identified by the letter f = female or m = male and a progressive number (visible enlarging the image). an educational experience about color emotion and its design implications 55 color culture and science journal vol. 12 (1) doi: 10.23738/ccsj.120106 compared to previous studies, these results seem to confirm for the hard–soft and heavy–light polarities the connection to the lightness attribute (ou et al. 2004a, gao and xin 2006). while for the cool–warm polarity the results of the palette developments seem to confirm the connection to the hue attribute (wright 1962) but not the connection with both hue and chroma (ou et al. 2004a, da pos and valenti 2007) or with chroma only (gao and xin 2006). in addition, the connection to the lightness attribute that emerged from the initial exploration with the map, does not appear relevant in previous studies (da pos and valenti 2007). these results lead to some considerations with respect to the method adopted concerning the possibility of establishing associations between the selected connotative terms or emotion words and the color attributes both in absence of color samples and in presence of a high number of color samples and an even higher number of color combination possibilities (sivik and hård 1989). this way of proceeding, according to the students’ design training, contribute to validating the design opportunities offered by the possibility of dealing with the evaluation of the emotional response to color in terms of color combinations. the considerations on the outcomes of the second phase, related to the contextualization of the emotion words and their related 4-color palettes, are limited to a didactic evaluation of the experimented design process. design students are generally used to work with the possibilities of establishing associations between concepts, key words and visual syntheses. in the design process proposed in this experience the use of the evaluation of the emotional response to color allowed students to explore and evaluate a systematic approach to these associative experiences, starting from color in order to define the sensorial and emotional qualities of the environment. 4. conclusions the results of this educational experience and experimentation contribute to validating the design opportunities offered by the possibility of dealing with the evaluation of the emotional response to color in terms of color attributes, and thus of color combinations. in addition, the use of such associative assumptions to build the emotional character of an interior space seemed to be a useful educational and methodological tool to relate color to the other design components, in particular shape, material and surfaces, and to show the potential value of a design process structured around color and the evaluation of the emotional qualities of the environment. 5. conflict of interest declaration the author declares no conflict of interest related to this publication. 6. funding source declaration this research did not receive any specific grant from funding agencies in the public, commercial, or not-forprofit sector. 7. short biography of the author cristina boeri is an architect phd, her activity in the research, teaching and professional sectors, deals with aspects related to the color perception and design. since 2001, she carries out educational and research activities in the color lab of the department of design of the politecnico di milano. she is adjunct professor of color and perception at the school of design, politecnico di milano. notes [1] for color attribute definitions see kuehni, r. g. (2003). color space and its divisions. color order from antiquity to the present. hoboken: wiley and sons. in this paper, the terms used to define the color attributes in the respective studies reported have been kept. [2] compared to the ten bipolar color-emotion scales used in the experiment of ou et al. (2004a:233) as the most frequently used in early studies (warm-cool, heavy-light, modern-classical, clean-dirty, activepassive, hard-soft, tense-relaxed, fresh-stale, masculine-feminine, and like-dislike), the opposites warm-cool, heavy-light, hard-soft were selected; modern-classic was preferred to modern-classical; dynamicquiet was preferred to active-passive. references boeri, c. (2019) ‘an educational experience on the exploration and experimentation of colour associations and relationships’, journal of the international colour association, 24, pp. 1–10. castelli trini, c. (1995) ‘states of domesticity’, the dream of power: reality and utopia in home automation, casciani, s. 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(1981) non-visual effects of light and colour. annotated bibliography. stockholm: the swedish council for building research. nakamura, t., sakolnakorn, p. n., hansuebsai, a., pungrassamee, p. and sato, t. (2005) ‘emotion induced from colour and its language expression’ aic 2004 color and paints, proceedings of the interim meeting of the international color association, caivano j. l. and struck h.-p. (eds.) porto alegre: associação brasileira da cor, pp. 328–331. osgood e. c., suci g. j. and tannenbaum p. h. (1957) the measurement of meaning. urbana: university of illinois press. ou, l-c., luo, m. r., woodcock, a. and wright a. (2004a) ‘a study of colour emotion and colour preference. part i: colour emotions for single colours’, color research and application, 29, pp. 232–240. ou, l-c., luo, m. r., woodcock, a. and wright a. (2004b) ‘a study of colour emotion and colour preference. part ii: colour emotions for two-colour combinations’, color research and application, 29, pp. 292–298. sivik, l. (1970) ‘om färgers betydelse’ [english summary: colour connotations and perceptive variables]. stockholm: swedish colour center. sivik, l. (1989) ‘research on the meanings of color combinations’ aic color 89, proceedings of the 6th congress of the international color association, 2, buenos aires: grupo argentino del color, pp. 130–132. sivik, l. and hård, a. (1989) ‘on studying color combinations: some reflexions and preliminary experiments’. färgrapport 22, stockholm: scandinavian colour institute. wright, b. (1962) ‘the influence of hue, lightness, and saturation on apparent warmth and weight’, the american journal of psychology, 75(2), pp. 232–241. 89 color culture and science journal vol. 12 (1) column: book reviews verena m. schindler art and architectural historian, zollikon, switzerland. ecd.studygroup@yahoo.com these reviews of three books – jean-philippe lenclos: painter & designer (2017), colour strategies in architecture (2015), and farbraum stadt: farbkultur in winterthur (2019) – address colour in urban and architectural design. jean-philippe lenclos: painter & designer (2017) the cover of this book shows a glass vase on a table with a bouquet forming a natural colour palette including bright yellow forsythia, purplish wisteria, branches of an orange-red flowering japanese ornamental apple tree and of a white blooming cherry tree, and black-brown shoots with green leaves. on the right, a watercolour depicts the colour harmony of the natural floral arrangement. at the top, the word ‘art’ repeated on a skyblue background is perceptible as well as the photograph of a young person whose eyes enigmatically peer in between the leaves. in the centre, a rather dominant white square pierces this picture like a window which – according to ancient feng shui beliefs – clears the path for the dragon, symbol of positive energy and good luck. four threads or lines cross in the opening to represent the intersection of different spiritual forces: red stands for design, blue for research, green for teaching, and yellow for art. these are jean-philippe lenclos’ four fields of activity that comprise the four main chapters of the book. they are preceded by a chapter on his biography (childhood and youth) and followed at the end of the book by a chronology of events. the graphic design and layout were realized by the chinese graphic designer yuan youmin, professor at the china academy of art. the preface is by colour designer jianming song, who was lenclos’ first chinese student at the école nationale supérieure des arts décoratifs (ensad) in paris in 1985 and who published the first book on lenclos’ work in china in 1988. song’s wife di yin, who also studied for one semester with professor lenclos, founded her own agency plough color research co. ltd. in hangzhou and financially supported this publication. cloé pitiot, curator at the department of design, centre georges pompidou, who since 2018 has been a curator at the musée des arts décoratifs de paris, wrote the introduction. jean-philippe lenclos: painter & designer. 2017. text by jean-philippe lenclos. preface by jianming song. introduction by cloé pitiot. jinan: shandong fine arts publishing house. isbn 978-7-5330-6201-9 (chinese/english) translated into english and chinese, the main text is by french colour designer, researcher, artist, and teacher professor jean-philippe lenclos. the book is beautifully illustrated with approximately 730 images. in the first chapter, we learn that he studied at the art school in lille, then cabinet-making at école boulle in paris and also at ensad before sailing from marseille to japan where he enrolled at the kyoto school of art for two years – a crucial, shaping experience in his biography. the second chapter focusses on his work as a designer. for ten years he was artistic director of the paint company peintures gauthier before creating supergraphics and founding his own agency atelier 3d couleur in paris in 1978. the atelier’s focus was on colour design in urban planning, architecture, and for industrial sites. another important focus was on research on colour, materials, and new technologies in industrial 90 color culture and science journal vol. 12 (1) design including products, cars and textiles. the third chapter is dedicated to his famous concept ‘the geography of colour’, a systematic methodology he developed to study the colours of a village, town, or region. the fourth chapter is about his thirty-five years of teaching colour at ensad and includes his students’ work. the absolutely remarkable and longest chapter is the fifth, which describes his artistic research. he explores the properties of colours through his drawings, watercolours, and oil paintings. his artistic work creates vibrant optical patterns that capture light, rhythm, and movement similar to reflections on the surface of water. he deals with the fragile chromatic transformation of natural objects over time, beginning with very concrete examples and going beyond to the amazingly abstract play of colours and forms. fascinating secrets are revealed by this formerly unpublished material. as a conclusion, there is a timeline of his professional activities such as talks, publications, and exhibitions. this is a splendid book on the work of jean-philippe lenclos who not only furthered the profession of colour designer by creating a new dimension, but also influenced researchers, scholars, artists, and designers beyond france on an international level while serving as a leader and mentor, which is still true today. fiona mc lachlan et al.: colour strategies in architecture (2015) colour strategies in architecture is the outcome of a fortuitous encounter of three of the authors who initially crossed paths at the midterm meeting of the international colour association in 2011 in zurich. as a result, haus der farbe (house of colour – professional school for design in craft and architecture) in zurich and the university of edinburgh started a four-year interdisciplinary research project that investigated the strategic use of colour within architectural design practice. any material decision in architecture is tacitly a decision about colour, but the use of colour is not necessarily a strategic one. most of the time people are not aware of how different colours shape a building in a distinct way. colour has its own inherent qualities and is a key factor in creating the specific aesthetic and spatial experience of space. whether natural materials, pigmented layers, or finishes are applied, they define the relationships between planes, volumes, and details contributing to a particular atmosphere. colour strategies in architecture. 2015. texts by fiona mclachlan, annemarie neser, lino sibillano, marcella wenger-di gabriele, stefanie wettstein. preface by iain boyd white. basel: schwabe verlag in association with haus der farbe zurich. isbn 13: 978-3-7965-3421-8 (english) the research method was based on the discursive analysis of hand-painted samples (around 380) as well as on the development of an accessible way of communicating and disseminating the different approaches and findings. more specifically, the closely observed colours were studied and interpreted with the aims, first of all, of understanding and identifying the colour characteristics of a building or part of it; secondly, studying the colour strategy applied; and, thirdly, describing and discussing the context and approach in an illustrated essay. the book includes a selection of six different architectural practices that constitute the six chapters of the book and are titled the same as the essential aspects of the six depicted colour strategies: painterly promenade is the colour strategy attributed to the work of lux guyer (1894–1955), a pioneer female architect based in zurich; holistic interplay is the implicit colour strategy captured in the philharmornie and staatsbibliothek in berlin by hans scharoun (1893–1972); 91 color culture and science journal vol. 12 (1) tectonics clarified is the colour strategy illustrated by two edinburgh housing projects by basil spence (1907– 1976); immersive pop is the colour strategy identified in the design of several underground stations in west berlin by rainer rümmler (1929–2004); hushed tonalities is the colour strategy of the subtle and timeless approach of reiach & hall architects, whose firm was established in 1965; and, second layer is the colour strategy exemplified in two housing projects in zurich by contemporary swiss architects knapkiewicz & fickert. the findings of the fourteen case studies are summarized as a ‘colour portrait’ (tableau) and the colour strategy is visualized in a second larger unfolding plate. such plates recall the 2010 publication farbraum stadt: box zrh, which includes ninety-six colour portraits of selected buildings in zurich built over a century. in the conclusion the authors write that their expectations will have been fulfilled if the study encourages the strategic use of colour in architecture. the essays are highly interesting colour-centred analyses of architectural spaces. professionals will prove if the methodology developed in the book becomes the key to successful colour strategies in architectural practice. the plates are also currently travelling through europe as an exhibition. andres betschart et al.: farbraum stadt: farbkultur in winterthur (2019) the history of the city of winterthur goes back to the roman era, but the city itself was granted borough rights only in 1264. as in most swiss cities, the ancient city core is colourful. each building façade is a different colour and this contributes to the creation of the particular ambience of this public space. in the preface, winterthur’s mayor michael künzli claims that the book farbraum stadt: farbkultur in winterthur (colour space and city: colour culture in winterthur) and its colour charts are useful as a basis for discussing colour, making sound colour decisions, and drawing attention to characteristic colour features and local colour traditions. released as a boxed set, the publication contains a book, a folded leaflet, and three folded posters. there are several essays in the book. in one, architect stefan gasser claims that colour regulations are important and describes how a façade that was recently painted vibrant farbraum stadt: farbkultur in winterthur. 2019. texts by andres betschart, stefan gasser, basil marty, marcella wenger-di gabriele, stefanie wettstein, jasmin widmer. preface by michael künzli. (neujahrsblatt der stadtbibliothek winterthur; bd. 356.2019) winterthur: stadtbibliothek winterthur, isbn 978-3-908050-44-5; zürich: chronos verlag, isbn 978-3-0340-1509-7 (german) orange prompted immediate criticism from many inhabitants. (in his essay, the author, however, does not mention whether or not the owner was forced to repaint the façade.) gasser also describes how in 1943 winterthur’s city core became a protected zone – including in terms of colour design – and that the urban planning act of 1975 states that the overall colour character should be preserved in the old city centre. in another essay, art and architectural historians basil marty and jasmin widmer point out that colour regulations are not a contemporary invention citing a dispute in 1629. the authors examine additional archival documents from 1648, 1810–1818 and 1926 discussing the historical development of colour in urban planning and social impact of colour on architecture. in a third essay, historian andres betschart explores the 1910s and 1920s colour movement launched by bruno taut in germany and how the 1926 exhibition die farbige stadt (the colourful city) at winterthur’s gewerbemuseum was immensely popular. betschart includes reproductions of autochromes by photographer hermann linck as well as the 1926 colour design proposal for one of winterthur’s main streets by artist willy dünner, whose mixed technique colour plates constitute the folded leaflet of the published set. the main chapter – and purpose of the book – is presented by marcella wenger-di gabriele and stefanie wettstein, who studied different districts to establish 92 color culture and science journal vol. 12 (1) colour charts as visual means of communication. these colour charts are included in the publication as folded posters. the first one relates to the old city centre and the urban core of a selected district. the second poster presents the colour charts of two heterogeneous districts. and, the third summarizes the colours of two garden cities. as directors of the haus der farbe in zurich, the authors developed a methodology and criteria to identify ‘good quality’ colours, i.e., colours that are typical and also well-fitted to a particular context. the colour charts represent a selection of the existing colours. as cultural and aesthetic judgements evolve over time, new additional colours can be chosen on the basis of and in harmony with the colour charts. the charts seem to represent the immediate appearance of the different colours on the façade surface (page 82, fig. 7). this raises an issue explored by karin fridell-anter in her study of 2000, whereby she demonstrated that façade colours shift greatly in terms of lightness and chromaticness when seen from a distance, as is usually the case. a further issue is that some of the colour charts include not only the colours of paint or plaster, but also of stone and of natural and varnished wood. are the authors correct in suggesting that dark brown could be applied on a plaster façade? under the keyword ‘façades’, the nature of the material associated with each colour is not explicitly stated. in one of the charts there are browns, dark browns, dark greens, and almost blacks, which are extremely somber colours for a façade and are generally responded to with harsh criticism from local residents. the colour charts are also problematic insofar as there are no reference numbers and dark colours are difficult to discriminate. concerning the colour charts of the heterogeneous city quarters, colours of natural materials, textiles, concrete, and paint fuse together. does the printed version make them appear harmonious? including the turquoise blue colour of existing buildings (pages 106–107) makes no sense as it would actually destroy the intended harmony. if these colour charts should be the basis for discussing colour, how do we deal with such colours? in sum, a useful colour chart for practical colour application entails much more than just analysing and summarising existing colours. the conclusion is by city architect jens andersen, who deals with the colour charts in daily practice. the book is nicely illustrated with contemporary photographs by michael erik haug. 75 color culture and science journal vol. 12 (1) doi: 10.23738/ccsj.120109 ceramic products and their chromatic ‘dna’ markers carla lobo1 1 school of arts and design, lida, polytechnic institute of leiria, caldas da rainha, portugal. ciaud, research centre for architecture, urbanism and design, fa/ulisboa, lisbon, portugal. corresponding author: carla lobo (carla.a.lobo@gmail.com) abstract originally produced with local raw materials and manufactured by ancestral processes, ceramic products have always been the result of knowledge transmitted from generation to generation. these artefacts reflect and reinterpret traditional, individual and collective formal vocabularies, integrating fragments of the day-to-day life of the local society, which conferred a geographical and sociocultural singularity revealing their local, regional, and national identities. from intrinsic to extrinsic characteristics, from raw materials to formal language, it is possible to find a plethora of combinatorial markers that characterize and differentiate these ceramic products – in other words, their ‘dna’. among such dna markers, colour has been a geographical and cultural ‘locator’ par excellence of ceramic products: either by the colouration of raw materials, or inks or glazes, or by adopted colour schemes, which reflect not only the local availability of pigments and oxides, but also local preferences and culture. furthermore, the characteristics of firing, an alchemical process, revealing a myriad of chromatic solutions based on acquired and arcane knowledge, confer a unique character to such ceramic products. the present globalization era has given way to the emergence of ‘transgenic’ ceramics, uprooted from their origins. despite the resurgence of the appreciation of local knowledge and traditions as a reaction to this scenario, can we still identify clear references to their origin – ceramic chromatic dna markers – even if these artefacts are the result of this ‘transgenic mutation’? the study substantiates that colour, as a dna marker of ceramic products still exists, and is associated to cultural identity. keywords colour, ceramics, product design, cultural identity, local received 23 october 2019; revised 29 november 2019; accepted 04 december 2019 ceramic products and their chromatic ‘dna’ markers 76 color culture and science journal vol. 12 (1) doi: 10.23738/ccsj.120109 1. introduction today we are witnessing the desire to recover and revitalize local identities, bringing them back up to date so they can emerge as current experiences. the evolution of the genetic code of ceramics is materialised in new shapes and visual syntaxes, where structural common denominators – dna markers – are recognised through their colour. common on-site denominators regarding different ceramics have been identified and considered as dna markers. such denominators gather unique information that is printed in the core of local ceramic production throughout generations. these dna markers are visible in ceramic products’ specific characteristics, including: the raw materials; affording technical characteristics (hardness, thermal and abrasion resistance); visual features (texture and colour); the product’s shape and size; the graphic elements; the pattern layout design; the colours and adopted colour schemes. these markers reflect not only the local availability of pigments and oxides, but also local preferences and culture. the combination of these markers results in distinctive formal languages, or dna ‘matrices’ that enable us to visually recognize the origins of a certain ceramic product. 2. methodology the conceptual framing of the study, as well as the operational constructs, are centred on the characteristics of ceramic artefacts (colour, brightness, materiality), and the territory where they are created and produced. for the present study, a practice-based methodology is adopted which includes the following process phases: a. visual and photographic survey: the analyticaldescriptive process of the visual features of ceramic products is related to the local natural environment, traditions and popular formal vocabulary. b. use of digital tools: picular, an app that associates keywords with images available on internet, is used to create a colour scheme with which to gauge if the visual imagery regarding the ceramic product of a given origin corresponds to reality. c. bibliographic review: a holistic approach to the subject is essential to the grounds for the assumptions set out. 3. ceramic colour ceramic colour is impacted by three factors: 1) raw materials; 2) firing; and 3) decoration. first, the combination of the raw materials that forms different ceramics (earthenware, terracotta, stoneware and porcelain) gives rise to the intrinsic colour of the ceramics (warm white, red, light yellow and cool white, in particular). the presence of certain compounds in clays such as iron oxide will contribute to the red of the terracotta, and the introduction of kaolin will contribute to the purity of the white porcelain. fig. 1. ceramic colour features (top, from left to right): a. ceramic raw materials and the effects of temperature on the ceramics’ colour body; b. ornamental patterns with glazes (transparent, semi-transparent and opaque glazes). other decor techniques (bottom, from left to right): hand painted in-glaze pigment; slip pipette underglaze; stencil brush; brush on fired glaze. photo: carla lobo. second, firing atmosphere and temperature determines not only the type of molecular structure of the ceramic product but can also directly influence the colour of the ceramic and its decoration. in the case of ceramic bodies rich in iron oxide, an increase in temperature represents a decrease in the luminosity of the red, and the characteristic red of the terracotta turns dark brown, in a reductive firing atmosphere (with little oxygen) the same red clay turns black (fig. 1a). the colouring agents used in the decoration change significantly under the action of heat, and at lower temperatures (around 1000°c) a varied and more saturated chromatic palette is possible than at 1400°c, where most of the oxides and pigments are significantly altered, and the chromatic palette tends to be less saturated. ceramic glazes show a high chromatic durability after being subjected to high temperatures. according to fairman and hemmendinger (1998), the chromatic variation reported in colorimetric terms was ceramic products and their chromatic ‘dna’ markers 77 color culture and science journal vol. 12 (1) doi: 10.23738/ccsj.120109 considered insignificant. for over 20 years, there was no change in values higher than 0.5 cie lab units was found. third, as far as decoration is concerned there are multiple possibilities ranging from glossy or matte coloured glazes, transparent or opaque glazes (fig. 1b), the underglaze and in-glaze inks and coloured slips that can be applied over the biscuit fired (fired ceramic body) or over the glaze in a wide range of colour combinations (fig. 1c). the extrinsic colour is determined by the combination of the colour(s) of the glaze(s), paints and slips, and the ceramic body. when the glaze is opaque, the colour of the piece will be the colour of the glaze; when the glaze is transparent, the perceived colour will be the combination of the colour of the glaze and the colour of the ceramic body. the thicker the layer of glaze, the more saturated the perceived colour will be. when there is decoration, the chromatic intersection is even richer, involving the colour of the ceramic body, the colour of the glaze and the colour of the paints and slips. the different ways of articulating these factors together with specific colour schemes define the chromatic characteristics of ceramic products. this singular composition is transversal to the region’s ceramic artefacts and defines the chromatic dna of its ceramics. 4. cultural colour schemes: unique or a fusion? the discovery of the maritime routes between europe and the far east in the 15th century boosted the spread of oriental products in countries with ports along these routes. chinese porcelain achieved great success in european markets, with a strong influence on european ceramic production. portugal and the netherlands were two important distribution centres along these routes. clear influence of chinese porcelain in both countries’ ceramics can be found in both the formal vocabulary and in the colours used (fig. 2 and fig. 3). other ancient routes, such as the silk and spice land routes, explain clear similarities between the different chromatic palettes of pottery – intense blues and yellows found in the middle east (uzbekistan, iran and egypt) were also found in north african pottery (tunisia and morocco) and further to the iberian peninsula and italy. the island of mallorca, in the western mediterranean region, was the starting point for the arab-influenced plates manufactured in spain to reach italy, where they were an inspiration for the majolica (phonetic deformation of the name of the island of mallorca) of urbino (costa 2000). the 15th and 16th centuries iberian sea journeys took the ceramics’ shapes and colours to central and south america, where even today traces of this legacy exist, both in terms of heritage as well as within the current artistic and industrial production, particularly in mexico and brazil (fig. 2). fig. 2. chinese porcelain influence (from left to right): 19thcentury chinese porcelain; 18th-century delft tiles; 17thcentury portuguese tiles; moorish-influenced moroccan tiles, early 20th century; spanish tiles (photo: carla lobo). and 18th-century mexican tiles (photo: mexicanarchitecture.org). in the early days of glazed ceramics production (6th century b.c.), the glazes were transparent, so the colour of the ceramic body could be seen. only white porcelain, after being baked, was close to the idea of the white ‘canvas’ for paintings. to get the same contrast, a white slip was used on the ceramic body in order to hide the colour of the ceramic paste, which was then covered by a transparent lead glaze. this was not ideal once the transparent lead glaze turned yellowish the white slip background. in the 9th century, the discovery of tin as a white colorant for glazes, allowed its use as a base for decoration, closer to porcelain. the oxides used to give colour to the glazes, which are also used in the stains applied to the motifs painted on the glazes, were naturally selected for their resistance to the high temperatures inherent to ceramic production. before industrial alternatives to natural oxides were found, the colouring sources of glazes were common in all countries that produced glazed ceramic products, and it was possible to distinguish which ones had this natural resource, and those that imported it, by the abundant or scarce presence in the pieces they produced. for example, since 2000 b.c. cobalt blue, a natural resource in the persian region, was very common in ceramic artefacts. in europe, it began to be widely used only in the 13th century. 4.1. materials and place local variations in raw materials impact their appearance. for example, chinese kaolin creates a whiter porcelain than portuguese kaolin. dutch cobalt blue is different from middle eastern, mexican and chinese cobalt blues, as seen in figure 2. in 14th century china, local cobalt produced a greyish, unsaturated blue, compared to middle eastern blues. cobalt was therefore imported from persia, added to the local cobalt, and produced a more saturated and visually rich colour. (trindade 2009) (fig. 3). ceramic products and their chromatic ‘dna’ markers 78 color culture and science journal vol. 12 (1) doi: 10.23738/ccsj.120109 fig. 3. cobalt blue and its use in different places (from left to right): 19th-century chinese pot; 17th-century turkish tiles (photo: carla lobo); 18th-century dutch plate (photo: © jenny jensen). and 19th-century portuguese plate (photo: carla lobo). likewise, the minerals in the water used in the ceramic manufacturing process impact the tonality of the ceramic body, glazes and paints. even if the raw materials are the same, the resulting colour can vary, and is intrinsically related to the specificity of place (swirnoff 2000, finlay 2002). swirnoff emphasises the link between raw materials and local colours, relating colours present in the local environment to cultural sensitivities to colour. there are chromatic preferences, intrinsic to socio-cultural heritage and clearly related to soil composition, flora, climate and the quality of local light. these factors along with formal vocabulary reflect culture and folklore, create specific chromatic syntaxes in harmony with the setting, enabling us to identify their origin (lobo and durão 2011, shu 2009, weston 2008). this perspective may explain why cobalt blue entered portugal in the 13th century, via spain, brought by iraqi refugee potters who travelled through north africa until they reached the iberian peninsula. its use in spanish ceramics was not as intensive as in portugal, with green, yellow, manganese and white (of the same origin as cobalt) forming the base of the spanish palette rather than blue (trindade 2009). in portugal, however, cobalt blue became one of the most significant colours in the national colour vocabulary and was found in artefacts from all regions of the country, although more common in certain geographical areas and product typologies (fig. 3, fig. 5 b and fig. 6 d). picular was used in an attempt to establish a connection between the collective imagery of ceramic colour from a country, and its ceramic creation and production. the colour schemes on the left of figures 4a, 4b, 5a and 5b were reached using the name of the country and ‘ceramic’ as keywords. comparing these colour schemes with photos of ceramic artefacts from the same countries, allowed to conclude that a local chromatic identity may exist. fig. 4. ceramic colour imagery (from left to right): country comparisons of picular ceramic colour schemes with ceramic artefacts: a. turkish ceramic colours: turkish creamer, early 20th century (photo: © kütahya tiles and ceramics collection courtesy of suna and i̇nan kıraç foundation pera museum) and tiles, 18th-century (photo: carla lobo); b. moroccan ceramic colours: moroccan pot (photo: compliments of morocco travel blog and magazine 2013) and tiles, 15th-century (photo: carla lobo). fig. 5. ceramic colour imagery (from left to right): a. dutch ceramic colours: dutch plate, 18th-century (photo: © jenny jensen) and tiles (photo: carla lobo); b. portuguese ceramic colours: portuguese plate, early 20th century, and tiles, 17th century (photo: carla lobo). 4.2. portugal as a case study, a brief approach through trade and its geographical location, portugal has benefited from a range of inputs from different countries and cultures to generate a very specific and diversified chromatic language, specific in each ceramic typology, and in different geographical parts of the country. different chromatic syntaxes can be found in ceramic artefacts, from tiles to utilitarian and decorative crockery, which may also include figurative elements. these syntaxes are directly related to the raw materials available in situ and to local preferences. the blue and white tiles, in the 16th century (fig. 2 and fig. 6c), or the blue, white and yellow ones, more popular in the 17th century, as seen in figure 5b, are the most common colour schemes. although other colour schemes have also prevailed (cobalt blue, iron or antimony yellow, manganese purple or brown and copper green) since their proliferation at the beginning of the 17th century, these ceramic products and their chromatic ‘dna’ markers 79 color culture and science journal vol. 12 (1) doi: 10.23738/ccsj.120109 were the first to be recognised as the prevailing colour scheme of the portuguese tile – as their chromatic dna marker. in the northern and southern parts of the country red clay is very common; this is the reason why utilitarian pottery predominates, which is decorated with white slip in the north, and with a wide and quite saturated colour palette in the south. figure 6 a and c show examples of northern and southern portuguese pottery respectively. in the centre of the country we find greater diversity: from the red clay bricks and tiles to the white earthenware decorated in blue and white, or with transparent coloured glazes (fig. 6 b and b respectively). here there is an important utilitarian and decorative ceramic centre, caldas da rainha. in addition to its own formal vocabulary, the coloured transparent glazes are unique and an unmistakable reference to the identity of the glazed caldas pottery. the raw materials used to colour the local lead glazes (characterized by deep colours, an intense shine and a unique depth, only possible by the presence of lead) came from the local workshops. the lead came from waste pipes and was the base of all the glazes, the iron that made the ‘honey yellow’ colour came from the blacksmiths' workshops, others such as copper, manganese and cobalt oxides (green, brown and blue) had to be acquired (horta 2014). even today these four colours, which later included ‘cherry red’, are recognised as being the colours of the caldas glazes, colour markers of the ceramics of the region. figure 6 b shows an example of such work. fig. 6. portuguese ceramic colour schemes (from left to right): a. traditional red clay slipware (north of portugal); b. caldas da rainha coloured glazes (photo: carla lobo); c. red pottery from the alentejo (south of portugal) (photo © heranças do alentejo); d. 18th-century tiles in lisbon (photo: carla lobo). 5. new syntaxes, same identity: colour as a dna marker of ceramic products we highlight some transnational examples, where the projects’ authors clearly assume the role of colour as a dna marker: figure 7a presents “ceramic house” by wang shu and zhou wu (ceramist), in jinhua, china, 2006. the house is covered in “ceramic tiles that were the products of youse (ceramic color)” (shu 2009), glazed in 40 colours extracted from the chromatic palette of traditional zhejiang ceramics (mainly celadon greens and browns) in order to create the perfect adaptation of architecture to the place, while also respecting and appreciating the local identity. “colors are arranged irregularly, however it presents all the colors in chinese ceramic” (shu 2009:83). figure 7b presents oceanário, tile cladding by ivan chermayeff, in lisbon, portugal, 1998. in this work, the decision to use blue and white tiles, developed from moorish inspiration motifs, was based on the recognition of the tile as a native material of lisbon architecture, namely the cobalt blue and white pattern tiles. the wavy surface of the tile alludes to the seas and oceans, where the cobalt blue is applied with a sponge to reinforce the irregularity of the water surface. the selection of patterns is based on the assumption of establishing a scale of light gradients, from white to dark blue, which enable the construction of images perceived as volumetric through the optical mixture of these gradients. this chromatic and formal vocabulary creates a coating that offers a moving observer different perceptions of the surface depending on the distance and angle it is viewed. figure 7c presents barro preto by atelier bizarro, in vila real, portugal, 2017. returning to an ancestral portuguese technique of burning pieces in a reductive atmosphere, which gives them a black colouration, the ceramic products and their chromatic ‘dna’ markers 80 color culture and science journal vol. 12 (1) doi: 10.23738/ccsj.120109 studio developed a set of pieces with functions that are appropriate to the current modi vivendi, where the most obvious characterisation factor is the dark/black ash of the pieces. this technique has been part of unesco's list of intangible cultural heritage since 2016. figure 7d presents work by cerâmica do cabo, in pernambuco, brasil, 2006–2018. this project focussed on social integration and sustainability, where “each piece is developed from the appreciation of popular knowledge, the recognition of traditions, skills and the use of materials, […] (creating) product lines where shapes, textures and colours reflect the cultural and social values of the respective communities” (imaginário, 2006:29). several coloured glazes were developed, but only one was chosen, as it was compatible with the ceramic body. it was a simple and accessible formula that was easy to apply and with guaranteed results in firing without the artisan having to resort to experts from outside his or her community (d’garcia 2019). this is how “pernambuco blue” was born, which today is synonymous with cabo dinnerware. these examples show a direct link between ceramic colour and local identity, from the point of view of the persistence of these colour palettes over time and their roots (ceramic house, oceanário and bisarro); and, as in the case of pernambuco blue, the creation of a product where colour is one of the most outstanding factors, along with its originality and the ease with which it is recognised and associated with the production of a demarcated origin. fig. 7. new syntaxes, same identities (top, from left to right): chinese vase (photo: carla lobo); ceramic house (photo © evan chakroff); 19th-century moorish-inspired tiles; oceanário de lisboa (photo: carla lobo). and (bottom, from left to right): traditional black pottery from bisalhães (photo: carla lobo); pitcher from bisarro (photo © bisarro); pernambuco blue (photo © cerâmica do cabo). 6. final remarks we can say that colour of ceramic artefacts is clearly linked to the place where they were produced. furthermore, colour is only one of the characteristic aspects of these artefacts, closely linked and dependent on other tangible aspects (such as materials and manufacturing process), and intangible aspects (such as traditions and culture). it was possible to locate the origin of materials, colour schemes and formal vocabulary and how they have been adapted to local specificities, namely tangible and intangible aspects, creating specific chromatic syntaxes and defining local chromatic dna markers. the formal vocabularies of each region, the way they articulate the particular knowledge inherent to each stage of the process of conception and the manufacture of these artefacts, are the aspects that define the dna of their ceramics. in the specific case of colour, from the composition and firing of the ceramic paste to the quality of the ceramic surface and glazes, and from the decoration techniques to the colour schemes, an infinite number of potential solutions is possible, and is determined by the specific knowledge of each production nucleus. the comparison between the popular imagery of colour schemes of local regions identified through picular and the selected images of ceramic artefacts from the same regions showed common elements – their chromatic dna markers – that express the colour identity of ceramics from the formal and visual points of view. this paper presents the first steps of an ongoing research. though some evidences show that colour as a dna marker of ceramic products may exist, many possible starting points have been raised. 7. conflict of interest declaration the author certifies that she has no affiliations with or involvement in any organization or entity with any financial interest, or non-financial interest in the subject matter or materials discussed in this manuscript. 8. funding source declaration: the author received no funding for this work. 9. short biography of the author carla lobo designer, phd in design and master of colour in architecture. professor at esad cr polytechnic institute of leiria (product design and colour), with a ceramic products and their chromatic ‘dna’ markers 81 color culture and science journal vol. 12 (1) doi: 10.23738/ccsj.120109 professional and academic career based on research, experimentation and practice in the areas of ceramics, product design and colour. areas of interest: colour, ceramics, product design and public spaces. references d'garcia, g. (2019) ‘azul pernambuco’. private communication. available from the author. fairman, h. s. and hemmendinger, h. (1998) ‘stability of ceramic color reflectance standards. color research and application. 23(6), pp. 408– 415. finlay, v. (2002) colour: travel through the paint box. london: sceptre. horta, c. (2014) manuel mafra (1831–1905) e as origens da cerâmica artística das caldas da rainha. doctoral thesis. universidade de lisboa. http://hdl.handle.net/10451/11311. imaginário pernambucano: design, cultura, inclusão social e desenvolvimento sustentável. (2006) recife: zoludesign. https://www.oimaginario.com.br/producao-academica (accessed: 12 june 2019). lobo, c. and durão, m. 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(2008) materials, form and architecture. london: laurence king publishing ltd. http://hdl.handle.net/10451/11311 43 color culture and science journal vol. 13(1) doi: 10.23738/ccsj.130105 lighting and color design in the live music show between new technologies and practice andrea siniscalco dipartimento di design, politecnico di milano, andrea.siniscalco@polimi.it abstract the choice of light and color to complete the performance of a singer or performer in a live music show is an important and critical issue that can contribute to the success of the event. as part of the show, whether it’s a concert, a musical, or a fashion show, the lighting designer's design choices can make an event unforgettable or sink its quality invalidating the efforts of all the production. in this paper we introduce the evolution of this sector from a technological, methodological and research point of view, comparing it with today’s reality of the professional practice of the stage lighting designer. keywords: live show, lighting, color, performance, led. received 22/12/2021; revised 31/03/2021; accepted 04/03/2021 lighting and color design in the live music show between new technologies and practice 44 color culture and science journal vol. 13 (1) doi: 10.23738/ccsj.130105 1. introduction there are many factors that affect the choice of color for each single song of a show; for example, the personal interpretation given by the sensibility of the designer who can "feel" a specific color and its shades, more appropriate for the staging of the song. you can also make choices related to the different stages of the show, in order to create a sort of "color narration", bringing dominant colors to the stage for more consecutive songs, giving the perception of "monochromatic" periods within a more vast scheme of interpretation, which will evolve later, recalling an imaginary and transmitting different sensations to the viewer so as to accompany him emotionally through the path of the show. fig. 1. albert sperr lighting at zeppelinfeld stadium in nuremberg 1934. courtesy german federal archive. the use of artificial lighting as a stage tool began to spread in the 20s of the last century when cinema, from the first experiences of theatrical shooting in plen-air, started production in indoor film studios. the masters of photography discovered the importance of scenographic light as a communication tool. a turning point in this area was fritz lang's 1927 film metropolis. in this film, the luminous coding assumes a semiotic value, in the management of light and shadow, in the dynamic projections, in the use of electric discharges and luminous objects, as scenographic communication tools, able to amplify the effect of the scenes on human emotions (roth, 1978). lang drew his inspirations from art deco, bauahus and futurism (rutsky, 1993; wolfe, 2020) applying them to light, which from a scientific and technological subject became a communicative, scenographic and design tool (pooky, 2016). in the following years it was not only cinema that drew inspiration from the scenographic and communicative use of light. in 1933 albert speer, the nazi architect, aware that he would not have had time to build the zeppelinfeld stadium in time for the 1934 annual party meeting, decided to use light as a building material. he used 152 anti-aircraft floodlights loaned by the luftwaffe to delineate the boundaries of the stadium in a space in nuremberg that could hold up to 340,000 people. the british ambassador henderson, described it as “sacred and beautiful cathedral of ice”, while the french ambassador francois-poncet defined it as “a mystical ecstasy, an holy illusion” (speer, 1970). the communicative effect was such that even in the following years the same set-up was used. in the documetary the triumph of the will (by leni riefenstahl), about the 1934 nuremberg party rally, music was also used: as part of the soundtrack she used wagner's die meistersinger (moller, 1980). the aim was to emotionally involve the viewer through a synaesthetic interweaving of the two senses, sight and hearing, which are the basis of remote communication. light, music and, with the end of the era of black and white, color arrived on the stage. as evidenced by (applebee, 1950), the introduction of color through lighting was already beginning in post-war british theaters. even decades before the advent of leds (strange and hewitt, 1956) cite the example of the theatrical experience as a possible model of experimentation to determine the quantity and chromaticity of general lighting to try to make it more pleasant for users. the issue of color also affects television stages, posing serious problems with regards to color rendering as a function of different lighting setups. one of the first television stages was created at the bbc with the possibility of remotely controlling up to 100 different intensity configurations of the installed system. it arose also the problem of obtaining the first color filters capable of withstanding high temperatures for a long time (ackerman, 1969). the relationship of light with the subject of the representation was defined by (reid, 1970) as the art and science of the stage lighting. in his description, this is an activity that must manage three fundamental variables of light: intensity, color and direction, which are the syntactic elements on which to design selective, atmospheric and dimensional lighting that should be suitable for the context of the representation. after the color, a further innovation took place in the 1980s by vari-lite with the introduction on the market of moving lights. these light projectors are able to rotate the emission of the light beam on two axes and to control the color thanks to the use of dichroic filters. from those lighting and color design in the live music show between new technologies and practice 45 color culture and science journal vol. 13 (1) doi: 10.23738/ccsj.130105 years onwards, stage lighting has become dynamic in live music shows, theater and television stages. a turning point in the live music show came with pink floyd's the wall concerts, whose lighting design marked a difference from previous live music shows (williams, 1988). and from those years, even in theatrical (taylor, 1989) and television stages, dynamic lighting began to become a new expressive variable, used to amplify the communicative power of light in representation, which was also celebrated in the showlight'89 conference, made in collaboration with the cie (ackerman, 1990). in the following years, the professional approach to the design of the live music show events was the subject of further researches at the marketing level where light and color always played a role of primary importance (minor et al., 2004; moody and dexter, 2009). since this is a business, mathematical models have been defined to evaluate the level of satisfaction of the participants in live music shows (hausman, 2011). some scientific and applied research has also been done on the relationship between color and music (pridmore, 1992; caivano, 1994; lindborg and friberg, 2015; whiteford et al., 2018),and this is a research topic still open worldwide. some preliminary research has recently been developed aimed at investigating the psychological response of users to the variation of the luminous patterns of a concert (lo and steemers, 2020) and the environmental colors of the concert halls (chen and cabrera, 2021). this area of research on stage lighting and color is anyway in an initial phase and, in order to be developed in the future, the degrees of freedom of the variables that come into play must be determined, which in the context of the live music show must be clearly determined. taste, interpretation and the experience of the lighting designer are always dominant in the dynamics of lights and chromatic choices, however, there are many factors that are inevitable and can affect the choices of the designers. as an example, an element certainly important is the will of the artist himself, who could have a clear chromatic vision of his songs and, consequently, pass it on to the lighting designer. the live stage field allows considerable freedom of intervention; greater than in other fields, such as fashion and television, where there are many more constraints. in live shows, there is no univocal approach regulated by standards. in this paper starting from world research in this sector and moving along the line of technological innovation, we have analyzed the experiential aspect of a famous italian lighting designer: giovanni pinna, active since 1986, who has worked with some of the major italian and international artists such as fabrizio de andre, pino daniele, adriano celentano, eros ramazzotti, luciano ligabue, vasco rossi, james taylor, ryuichi sakamoto, and many others. fig. 2, 3 two different moments of the building of the stage of the concert of vasco rossi in modena (2017). courtesy giovanni pinna. 2. project variables the design of lighting for a live stage show is not a simple task. thinking of it as a series of operations that lead to a result, it could be possible to compare it to an artistic or architectural activity. despite the freedom granted to the designer, there are numerous factors that make the preparation of the lights for a live show, a real lighting and color design in the live music show between new technologies and practice 46 color culture and science journal vol. 13 (1) doi: 10.23738/ccsj.130105 race against time; many steps and checks in a very short amount of time. first, the show venues are available just few days before the show itself, so it is not possible to "play ahead" (not much at least). this is also due to the high rental costs of the structures. the productions concentrate the dates of employment near the shows and of course, the lighting is only a part of the things to be done. designers are therefore faced with the need to carry out preparation and testing in just a few days, some more if the production is a major international event. working experience certainly helps in these cases; beyond the ability to find optimal solutions to possible unforeseen events, the knowledge of the various structures in which the shows are usually held (strengths and problems) for the artists with whom you work, is a very useful know-how for the lighting designer. in recent years, some software has also been developed that make it possible to prefigure the luminous and chromatic set-up of the live show, also considering the music and the dynamic temporal dimension of the lighting. software tools such as wysiwyg (cast, 2020), depence 2 (syncronorm, 2020), l8-software (l8, 2019), spotlight (vectorworks, 2020), and others that can help, simulating an installation; but as regards their use, there are different points of view on the part of professionals. some completely avoid these systems, others use them for a very early phase, while others use them more widely. it is mostly software that allow the professional to virtually rebuild the stage, even starting from the cad drawings of the set designers, and to go and install actual moving light projectors, simulating the control consoles. it is also possible to export files that allow a certain level of automatisms during the real show. the algorithms used by these digital tools, however, are not always very refined and the show simulated often does not have enough visual correspondence with the result, to the point that some designers do so easily without them. everything is then decided in the last days, and the lighting designer's artistic sensibility remains the essential tool; knowing how to read the various nuisance of the show and visually transpose them, improving their emotional charge. in addition to the timing and the geometrical characteristics of the venue, there are other external variables to be taken into consideration. when you are outdoors the concert usually begins while the sun has not yet completely set. the luminous envelope therefore evolves over the course of the show and it is necessary to adjust to adapt to the change. these changes in the color of the natural light atmosphere depend on numerous factors; place, season, time, weather conditions and these are almost always variables that can be evaluated only at the last moment, due to their very nature. another element that can significantly influence the color choices of the lighting designer is the presence of light deriving from other new technical equipment. the now constant presence of elements such as led-walls, which put in scene digital content which is not produced directly by the lighting designer. in addition to external factors and production variables, typical elements of the actual production of the show must also be taken into consideration. even just the type of engagement of the lighting designer, a contract with the production or directly with the artist, can affect the freedom of choice of the professional. then there are the other figures in the show; the most important is certainly the artist himself, who can have a personal vision of the show by making requests to the designer. as an example: vasco rossi, on the last tour asked for white and blue key colors for the song "gli angeli". these requests are not very frequent, but they can happen; in this case the designer must be able to mediate them with his own vision of the show. another very important actor is the set sesigner. the physical construction of space involving, geometries, materials and choice of surface colors, is extremely important for the choices of lighting and the maximum synergy between the two teams is desirable. 3. design degrees of freedom the project starts to form in the mind of the designer early, trying to build a "painting without colors", giving more importance to those that are the compartments of the scene, the orientation of the spot beams, of the washtype fillings, and so on. in this phase the color is only a vague anticipation; you can get an idea of what color could be used, but the information available is still not enough and the risk is to waste your work. it is at the time of staging, when everything goes into production, that it is possible to really give a color to the songs; work upwards, observing the "substance" of the light beams. very often the initial ideas had during the programming phase are rejected because they do not fit the rest of the scenic machine. the choice of colors is almost always the result of a personal interpretation. beyond the sporadic performer requests that might happen, it is the designer who chooses, through his musicality. the lighting designer can almost be considered an added musician who participates using time, measurements and lighting and color design in the live music show between new technologies and practice 47 color culture and science journal vol. 13 (1) doi: 10.23738/ccsj.130105 musical writing as a track to work on. it is essential to know perfectly the programmed repertoire to build its chromaticity, passing from framework to framework. fig. 4, 5, 6: white is the unifying color in the songs performer: vasco rossi. courtesy giovanni pinna. the freedom to be able to do all this then depends on the factors seen before, but also on the products available and on the designer's knowledge of them, which is mostly acquired through experience. entering into the heart of the choice of colors, in the specific case of giovanni pinna, color combinations are very contained. you can play on warm tones on warm, cold on cold, complementary colors and (but only rarely) in contrast unless it is necessary for a change of narrative. fig. 7, 8, 9. shift colors along the concert performer: vasco rossi. courtesy giovanni pinna. the chromatic shift marks the passage from one module of the show to another. often authors like to create narrative compartments composed of multiple songs and lighting and color design in the live music show between new technologies and practice 48 color culture and science journal vol. 13 (1) doi: 10.23738/ccsj.130105 a good choice is to keep the same colors within these segments, introducing different colors to move to the next compartment. the presence of natural light in the initial moments of the concert can be an issue, partly because of its intensity and partly because of the variability of its appearance. a possible approach to this condition is the use of neutral white light, adjuvated by a good quantity of artificial smoke, which gives an impression of diffuse glow, "naturally" luminous. this can be done while waiting for the sun to set completely and then to introduce the first color. this creates a very clear perceptive detachment with respect to the initial part of the concert which allows the public to immerse themselves even more in the programmed narrative contexts. 4. new technologies in addition to natural light, as already mentioned there are digital contents that are usually presented through led-walls or projections. the amount of light emitted by these devices is by no means negligible and their presence is now a must in major productions. fig. 10. led wall a created with barco creative leds (misphere) performers: u2. spanning from simple vertical elements able to change the perception of depth on the set, to actual modules scattered all over the stage; the amount of light and its coloring must be absolutely kept in consideration when designing light. it’s a good thing in fact that the lighting designer coordinate his work with the designer of digital content to create synergy and manageable choices. this can be greatly improved using media servers, which allow the integration of video content in the control consoles operated by the lighting staff, ensuring a good level of integration. usually, however, it is the lighting designer who, when he cannot make suggestions about the colors of the videos, must adapt to digital content in order to make harmonious light choices. fig. 11. a projection that overlaps the stage created with backtraxx and acronn screens performer: fedez. technology continues to improve in years, providing more possibilities every day: higher powers, more control and bright full saturated led colors. however, the flip side of these innovations is that as the possibilities increase, so does complexity. if we think of the shows of just some decades ago, everything was about using fixed beacons, colored gel filter; flexibility was less, but the preparation time was consequently very low compared to today. moving lights allow a very wide range of colors to be obtained, gobos to be implemented, light to be profiled, and multiplied with prisms, as each luminaire is potentially able to carry out the work of many. and then video projections, sets in transparency, special materials, platforms. a flexibility that was unthinkable until not long ago, but kind of overwhelming for the designer. the possibility of obtaining unlimited colors does not necessarily mean that this should be done. at times, using a fixed spotlight with a colored gel filter is still the most effective and economical choice, even if less elegant. the available budget is always the primary constraint of each project. this does not mean that technology should be avoided, on the contrary, today more than ever it is essential that professionals are prepared for the possibilities that products and systems have to offer, always keeping up to date in order to evaluate the best choices. regarding color, led light sources can produce more saturated colors with greater efficiency than using filters; obviously, we are not talking about the rendition of illuminated colors, but about the appearance of the light beam projected into the environment where artificial lighting and color design in the live music show between new technologies and practice 49 color culture and science journal vol. 13 (1) doi: 10.23738/ccsj.130105 smoke is dispersed. in terms of entertainment, the white remains a weak point of leds, making it less brilliant than the one created with metal halide lamps. some led sources are offered in rgbw format (red, green, blue and white) in order to give greater chromatic flexibility, but the result, from a white chromatic point of view, is still not comparable with that of discharge lamps. the same is true for sources that must provide a portion of uv for fluorescence, such as congo-blue, for which traditional lamps are still more appropriate. obviously, the digital sources are more flexible from a control point of view, but as mentioned above, too much flexibility, can extend the preparation time of the show. fig. 12, 13. led lamp moving lights with wash type projection clay paky a.leda b-eye k20 5. conclusions to conclude a last consideration regarding the led light sources. even in the entertainment industry now, solidstate lighting sources have conquered their position. although their dominance is not as established as in the architectural lighting field, the possibility to contain the power implied has led manufacturers to develop many devices that mount this type of lamps. from a chromatic point of view, however, the led sources still encounters resistances; some purists of gas discharge light sources prefer to avoid leds, opting for classic lamps, assisted by dichroic or gel filters. in the approach of giovanni pinna, the led sources find a wide space, mainly in the "wash" type headlights, the wide and adjustable beam with soft and indefinite contours that increase the brightness diffused in the space, while for the "spot" headlights, the beams with well-defined contours that are easily identifiable and create hard clear lines in the atmospheres of the show, still prefer discharge sources. fig. 14, 15: arc lamp moving lights with spot type projection clay paky supersharpy the future evolution of this sector will be influenced by technological innovation, but also by the methodological and marketing aspects presented in the introduction. at the end of the innovation, in a research (hsiao, chen and lee, 2017) (hsiao, chen and lee, 2017) proposed an automatic lighting control method, based on emotions due to music, through algorithms based on neural networks, whose application in the practice of lighting design is however very complex and far from the pretext of the lighting designer. to date and for many years the creative activity of the designer in the live music show lighting and color design in the live music show between new technologies and practice 50 color culture and science journal vol. 13 (1) doi: 10.23738/ccsj.130105 cannot be replaced by mathematical models or computer algorithms. years of experience are needed to be able to grasp every nuance of a performance and be able to act accordingly, making the best choice would it be technical or stylistic that is able to emphasize, dull down or even correct what is happening on stage. 6. conflict of interest declaration the author wish to state that no financial or personal interests have affected the objectivity of this study, and that no conflicts of interest exist. 7. funding source declaration author wish to state that no external funding has been involved for this study. 8. acknowledgment there are many people with whom i have had interesting insights on these topics over the years. the first thanks goes to giovanni pinna. i would also like to thank salvatore mancinelli and raffaele perin. finally, the clay paky and spotlight companies. 9. short biography of the author(s) andrea siniscalco msc in design in 2002 and phd in 2007 in the field of lighting fixture design. since 2003, he has been collaborating with the lab luce dip. design politecnico di milano. since 2008, he has been teaching lighting (design theory and cad methods) as adjunct professor at the school of design politecnico di milano. deputy director of the master’s in lighting design & technology. vice president of the gdc-associazione italiana colore. references ackerman, k. r. 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(1988) ‘floyd droids. marc brickman interview’, lighting dimensions magazine, 1 february. available at: https://pfco.neptunepinkfloyd.co.uk/band/interviews/other/otherbrick.htm l (accessed: 30 march 2021). wolfe, s. (2020) ‘fritz lang’s metropolis. how the iconic silent film took inspiration from art movements’, artland magazine, 11 december. available at: https://magazine.artland.com/fritz-langs-metropolis-howthe-iconic-silent-film-took-inspiration-from-art-movements/ (accessed: 30 march 2021). 62 color culture and science journal vol. 12 (2) doi: 10.23738/ccsj.120208 the restoration of the basilica minore di maria ss. incaldana in mondragone (northern campania): the role of color francesco miraglia1 1 dipartmento di architettura e disegno industriale, università degli studi della campania “l. vanvitelli”, aversa, italy. francescomiraglia@gmail.com corresponding author: francesco miraglia (francescomiraglia@gmail.com) abstract the basilica minore di maria ss. incaldana, located in mondragone (a city of northern campania), for many years was affected by many degradation pathologies. so, its restoration have been divided in: consolidation and replacement of deteriorated plasters of internal walls; painting of the internal walls with new colors; removal of the plaster on the left and right pillars of the central nave to analyse and date its masonry characterizations; painting of the façade. in the study phase we used a remote sensing thermographic camera to know its construction techniques and its pathologies in a non-invasive way. keywords restoration, thermographic analysis, stratigraphic analysis, sacred architecture received 03/02/2020; revised 03/07/2020; accepted 08/07/2020 the restoration of the basilica minore di maria ss. incaldana in mondragone (northern campania): the role of color 63 color culture and science journal vol. 12 (2) doi: 10.23738/ccsj.120208 1. introduction the restoration of the basilica minore di maria ss. incaldana in mondragone has made it possible to safeguard its interior and its external façade. the interventions were three: consolidation and replacement of deteriorated plasters; new colors for the internal walls; removal of the plaster of the left and right pillars of the central nave near the transept, creating stratigraphic windows. the restoration allowed to protect the church after many years of neglect and damage. 2. historical-constructive analysis the church was built by carafa family at the end of the 16th century, on a pre-existing and smaller sacred structure. the presence of this church is shown by some circular pillars made of tufa, placed around the original presbytery, discovered during the recent restoration work. the plant made by carafa family was divided into three naves culminating with three semi-circular apses, introduced by a wide transept surmounted by a mighty drum dome and an eight-spindle vault. the central nave was originally covered with a wooden structure, replaced over time by a barrel vault. instead, the side naves were, like today, covered by cross vaults (fig. 1). fig. 1. basilica minore di maria ss. incaldana, drone view before restoration work (ph: antonio smirne). the church revealed a basic project certainly drawn up by a master builder. the precise iconographic geometry of the sacred building wanted by the carafa, typical of the late gothic forms, is an expression of an art that is no longer spontaneous and popular, but desired by a wealthy client: the feudal lord. with the construction of the church, the three urban centers of the “terra di mondragone” in the early 17th century had four parish churches. an interesting description of the church is in the list of mondragone’s feudal properties compiled by the engineers galluccio and ruggiano after the death of prince carafa di stigliano (1690). however, this important historical document does not contain any information on its original colors. in the twenties of the 18th century the new feudal lords, the grillo of clarafuentes, carried out an intervention of restructuring and expansion, which led the church to its current conformation. among the various interventions carried out, there was the replacement of the roof of the central nave and the realization of the barrel vault which replaced the preexisting wooden roof. 3. restoration work several pathologies of degradation, according to the recommendations of the “ente italiano di unificazione” (uni 11182/2006), have been found in the church and on its external facade, mostly related to capillary rising damp. they are, for the internal environments: detachment, missing part (also found in other glossaries as lacuna), discolouration (also found in other glossaries as chromatic alteration), efflorescence (fig. 2). on the external surfaces, on the other hand, the pathologies found may refer to missing part, discolouration and crack. despite various analyzes of coloring and historical documents, no historicized colors were identified. fig. 2. basilica minore di maria ss. incaldana, left nave before restoration work. the restoration of the basilica minore di maria ss. incaldana in mondragone (northern campania): the role of color 64 color culture and science journal vol. 12 (2) doi: 10.23738/ccsj.120208 in the church has also been identified the presence of various layers of colouring, not breathable, affixed in recent decades. instead, on the external colourings it has still been possible to determine the shade, as the degradation has acted, as in most cases, on the intensity and saturation. in this way it was possible to reproduce the pre-existing chromatism of the external façade. it should also be noted the presence of rainwater infiltrations in correspondence of the upper surfaces of the sacred structure, due to widespread disconnections of the bituminous sheath above. the result was an accurate macroscopic analysis of this area, carried out with a limited margin of error. in the pre-intervention phase was used co called “remote sensing thermography”, for years the subject of great interest on the part of restoration operators, to detect the presence of any manifestations of moisture and/or lesions of plaster. it allows the visualization, in two dimensions, of the radiation measurement of the materials, using the thermal imaging camera, a device capable of detecting the temperatures of the bodies through the measurement of the intensity of infrared radiation emitted by them above absolute zero. thermography made it possible to visualize absolute values and temperature variations of the objects, to verify the presence of pathologies of the various stone elements (fig. 3). fig. 3. basilica minore di maria ss. incaldana, thermographic analysis. after identification of the deterioration phenomena, a series of interventions were carried out, outlined in accordance with the modern exercise of protection and the rules contained in the italian law called “codice dei beni culturali e del paesaggio” (d. lgs. 42/2004). restoration work was designed by architects francesco miraglia and corrado valente and directed by architect francesco miraglia. objectives of the interventions were: consolidation of the historicized plasters with integration of the compromised ones; redefinition of the colors, replacing the previous ones (dating back several decades and inadequate). during all phases of the interventions, constant attention was paid to eliminate the problems related to the widespread presence especially in indoor spaces of capillary rising damp, responsible for the presence and multiplication of biodeteriogenic organisms, favoured by the use, over the years, of cement-based plasters and fillers. plasters based on certified lime and selected aggregates were chosen to give a material support to the new colourings, also based on lime, that could prevent in the long term oxidation or loss of adhesion. the plaster additions, which concerned a significant portion of the vertical surfaces, were made using three products, with various grain sizes (fig. 4). fig. 4. basilica minore di maria ss. incaldana, right nave during restoration work. the restoration of the basilica minore di maria ss. incaldana in mondragone (northern campania): the role of color 65 color culture and science journal vol. 12 (2) doi: 10.23738/ccsj.120208 attention was also paid on the scientific analysis of the complex stratifications of the structure, through the creation of two stratigraphic windows on the pillars of the central nave, located in correspondence with the transept, to assume useful information on the presence of as many circular pillars in tufa, constituent of the original late 15th century church (fig. 5, fig. 6). 4. choice of new colors the new colors were chosen after having analysed the church from a historical point of view, assisted by the application of preliminary investigations and knowledge of construction techniques and constituent materials. after unsuccessfully searching for any chromatic evidence, it was decided to choose new colors. the choice of new colors for the interiors is based on the observation of the absence of historicized colors (evidently eliminated during previous interventions); this allowed the choice of the colors in order to meet the renewed needs of the worship building. fig. 5. basilica minore di maria ss. incaldana, left nave, stratigraphic window. fig. 6. basilica minore di maria ss. incaldana, right nave, stratigraphic window. the result was an overall analysis of the lighting criteria both natural and artificial of the interior spaces, in order to use softer and clearer colors. it was, therefore, aimed at making the sacred environment brighter, avoiding the previous visual context, which did not give back the right value to the membranes and finishes. the new colors, approved by the superintendence for architectural heritage and landscape, were also chosen for their figure: starting from a neutral color (white), they became, in correspondence with the upper portions of the structure (arches and vaults) more lively (sand and indigo) (fig. 7, fig. 8). fig. 7. basilica minore di maria ss. incaldana, testing of the new colors for the superintendence approvation. the restoration of the basilica minore di maria ss. incaldana in mondragone (northern campania): the role of color 66 color culture and science journal vol. 12 (2) doi: 10.23738/ccsj.120208 in order to restore the wide external front, instead, colors equal to the pre-existing ones have been identified, varying the brightness to make them softer. the white of the high overhanging pilasters, therefore, was interspersed with the yellow of the walls (fig. 9). 5. conclusions the restoration work has made it possible to eliminate the pathologies of degradation of the church. in addition, they have made it possible to restore the sacred building to a more harmonious figural condition, eliminating the chromatic chaos especially in the interior, caused by decades of deplorable neglect and inadequate interventions. fig. 8. basilica minore di maria ss. incaldana, central nave after restoration work (ph: angelo razzano). 6. conflict of interest declaration this research did not hold any conflict of interest. 7. funding source declaration this research did not receive any grant. fig. 9. basilica minore di maria ss. incaldana, external façade after restoration work (ph: angelo razzano). 7. funding source declaration this research did not receive any grant. 8. short biography of the author francesco miraglia architect, ph.d. in conservation of architectural heritage, former honorary officer for the protection and supervision of the architectural heritage in the provinces of caserta and benevento (mibact), former adjunct professor of “caratteri costruttivi dell’edilizia storica” (università della campania). author of many studies on the protection of cultural heritage, he is the coordinator of the scientific committee of “terra laboris. itinerari di ricerca” (caramanica editore). since 2006 he has been a member of “società napoletana di storia patria” (naples). since 2017 he has been an ordinary member of “centro di studi per la storia dell’architettura” (rome). since 2019 he has been a member of “istituto italiano dei castelli”. his professional activity is focused on the conservation of cultural heritage. references crova, c., miraglia, f. (2018), use and efficacy of thermography for stratigraphic analysis of historical buildings, in «conservation science in cultural heritage», 18. miraglia, f., valente, c. (2018), il restauro della basilica minore di maria ss. incaldana a mondragone. metodologia, interventi, prospettive di ricerca, caramanica editore, marina di minturno. alagna, s. (2008), stratigrafia per il restauro architettonico. il metodo dell’analisi stratigrafica delle superfici murarie per la conoscenza e la conservazione del costruito storico, aracne editrice, roma. conti, c., martines, g. (2007), i saggi e le indagini preliminari, in carbonara, g., a cura di, trattato di restauro architettonico, 2, utet, torino, pp. 587-600. valente, c. (2005), mondragone sacra. viaggio nella memoria dello spirito, caramanica editore, marina di minturno. bellini, a. (1996), tecniche per la conservazione, franco angeli, milano. 16 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140102 the jos-pe process in the jacob merkelbach collection at the rijksmuseum in amsterdam laura covarsí rijksmuseum, amsterdam, the netherlands, lcovarsi@gmail.com abstract the rijksmuseum in amsterdam holds a collection of 208 photographs from the merkelbach studio (19071961 in amsterdam). at least 28 of them were made with the jos-pe technique, which was invented in hamburg in 1924 and remained in use for 20 years. this dye imbibition process is part of the early history of commercial color photography. this research project began with the characterization and visual examination of jos-pe prints on paper and three-color printing matrices on glass that are part of the rijksmuseum’s merkelbach collection. the rijksmuseum jos-pe prints and plates, as well as (aged) mock-ups were analyzed with different techniques: specular light, uv fluorescence, microscopy, xrf and liquid chromatography uplc. a cross section obtained from an unexposed jos-pe paper made it possible to determine the prints ’structure: a paper coated with a thin layer of barium sulfate, topped with a thin layer of gelatin. the analyzed glass plates revealed the use of dyes such as carmine, induline blue and dianil yellow 2r. fading tests performed on mock-ups made of the red dye showed a blue wool standard (bws) lightfastness of 1-2. the fading tests of the other two dyes were not performed. the specialized literature points out the lightfastness of the blue dye as 4 and 2-3 bws for the yellow dye. keywords jos-pe, jacob merkelbach, dye-imbibition, rijksmuseum, subtractive color photography, three color photography received 02/12/2021; revised 28/12/2021; accepted 03/01/2022 the jos-pe process in the jacob merkelbach collection at the rijksmuseum in amsterdam 17 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140102 1. introduction the merkelbach collection held at the rijksmuseum in amsterdam offers an interesting corpus for studying the industry of photographic processes and its evolution; with 13 different photographic processes the collection presents a very good example of the commercial photography in use those days, between the 1920’s and 1940’s. the jos-pe prints in the collection are probably the most interesting objects in this group of photographs (fig. 1). the general lack of technical data on the process and the materials creates challenges for the conservation of these photographs. the objective of the research carried out in 2018 and 2019 was to study the material components of the prints and to examine the sensitivity of the image-forming dyes to factors such as light and oxygen, in order to evaluate exposure levels for exhibitions and loans. 2. jacob merkelbach and the studio merkelbach jacob merkelbach was born in amsterdam in 1877. during the first years of his professional career, he worked in a business belonging to his father and his brother-in-law: m.h. laddé & j.w. merkelbach, a shop selling magic lanterns, film and photographic materials and also the first film studio in the netherlands (hegeman and leijerzapf, 1985). for a short period, merkelbach worked in the film industry until he opened his own studio, in 1913. it was located in a fashion house, on the fifth floor of the luxurious hirsch & cie in the leidseplein building in amsterdam. he worked mainly on commercial portraits, and his clients came from the high society of amsterdam. merkelbach also worked for the theatre and dance world, producing many of the promotional images of actors and dancers of the dutch scene. his frequent collaboration with the commercial galleries where the studio was located could be seen in the showcases of the ground floor, where merkelbach often showed fashion photographs. the studio offered its clients numerous and diverse techniques, from bromide photographic papers to pigment processes such as carbon prints or jos-pe prints (which are the focus of this research). the negatives on glass were heavily manipulated by the retouchers of the studio, as in european studio photography at the time, which was a great inspiration for jacob merkelbach. it was one of the most important studios in amsterdam in the period between the wars. jacob merkelbach died in 1942 and his daughter mies continued the business until the 1960's, when the studio was closed for good (veen et al., 2013). during the last years, mies merkelbach sold what was left of the collection (negatives and prints) to different buyers and institutions. in that period, the dutch collector bert hartkamp bought a group of 200 prints on paper, a group that later became part of the rijksmuseum collection. other artworks produced by studio merkelbach can be found in the special collections at the university of leiden, the amsterdam city archives (stadsarchief), the dutch institute for theater in amsterdam (theater instituut nederland) and the jewish historical museum in amsterdam (joods historisch museum). fig. 1. portret van een vrouw in een rode jurk, jacob merkelbach, 1920-1930. rp-f-f03962 rijksmuseum. 3. the jos-pe process jos-pe is the name of a photographic process registered by a company of the same name in munich, germany, in 1924, founded by the photographer and inventor gustav koppmann and josef-peter walker (from whom the process takes its name). in 1926 the company moves to hamburg. after bankrupt in 1931, a fellow customer, franz vollmer, takes over the company from 1934 until 1943, when a bomb destroyed the factory on the 25th of july (koshofer, 2013; thiele, 2006). the jos-pe process in the jacob merkelbach collection at the rijksmuseum in amsterdam 18 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140102 this technique is included in the group of the dye imbibition processes, together with other processes such as sanger-shepherd, pinatype or kodak dye transfer. it is a subtractive three-color process in which the print is made with three relief printing plates, blue, red and yellow, made from three color separation negatives (pénichon, 2013). the process relies on the capacity of gelatin to absorb or release dyes when in contact with another layer of gelatin. 4. the special jos-pe camera more than merely a photographic process, jos-pe was a complete printing system that offered the photographer all the necessary materials for printing in color. this included the special and advanced “jos-pe camera” which allowed the photographer to make the three-color separation negatives in one shot, avoiding the undesirable effect of time-parallax misalignments and allowing the photographer to take pictures of moving objects or portraits in color (fig. 2). until then, color separation negatives had been obtained in nonsynchronized cameras or sledge-cameras such as the dr. miethe three-color camera, produced by wilhelm bermpohl since 1903, and also offered by the jos-pe company in its catalogue. fig. 2. jos-pe catalogue. ca. 1930 the camera was constructed in a trapezoidal shape, with a lens in the front, built by zeiss, and two mirrors manufactured by steinheil sohne located behind the lens (jos-pe farbenfoto, 1930). this group of mirrors split the incoming beam of light into three individual beams, which exposed the three negatives located in the back of the camera through the corresponding color filters: red (in front of the lens), green and violet-blue, made with dyed gelatin sheets sealed between glass and located exactly before the glass negatives, next to the plate holders. focusing was done with the aid of a ring in the front of the camera, set under the lens, and checked on the ground glass of the back, where later the plate holders were placed. in this manner, three black-and-white negatives on glass were obtained. the jos-pe catalogue offered two cameras for two types of consumers: amateur and professional (uka type). the differences lay in the size of the negatives: 4.5x6 cm or 9x12 cm, and certain features like the speed of the shutter and the quality of the materials used to construct the camera. the price difference between one and the other was substantial: 950 rm or 3000 rm (reichsmark). the jos-pe camera was probably one of the greatest contributions made by the jos-pe company to the color photography industry. it was inspired by the camera patented by frederic eugene ives in 1899 (ives, 1899) in which mirrors were used to split the beam of light inside the body of the camera (fig. 3). fig. 3. photographic camera. f.e.ives. 1899. us patent. 5. the three-color jos-pe printing technology in the jos-pe process, the three relief printing plates on glass used to obtain the final prints on paper were obtained from three black-and-white negatives made with the jos-pe camera. the glass negatives (fig. 4) were coated with a bromide silver gelatin emulsion. due to the division of light inside of the camera, the quantity of light received by each negative varied: 25% of the light reached the blue and yellow plates and 50% exposed the red one (jos-pe farbenfoto, 1930). the sensitivity of the jos-pe glass negatives and the thickness of the color filters was adjusted to this. some authors suggested that other panchromatic glass plates could be used, although the jos-pe process in the jacob merkelbach collection at the rijksmuseum in amsterdam 19 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140102 the proprietary ones were specially fast (taking in account that the exposure was made through color filters that reduced the quantity of light reaching the negatives). due to the high sensitivity of the emulsion, working under red light was not recommended. the development of the glass negatives must be done in complete darkness, unless a desensitizer was used in the process (willekens, 1926). fig. 4. jos-pe separation negatives and printing plates on glass. j. merkelbach. rp-f-f26749-1/2/3 and rp-f-f26748 2/3/4. rijksmuseum. from the three negatives, the three printing plates (fig. 4), or matrices, were enlarged to one of the common available formats (10x15 cm, 13x18 cm, 18x24 cm, 24x30 cm, 30x40 cm). the ensuing print would be made by contact. the matrices were manufactured on glass and also coated with a gelatin silver bromide emulsion. the positive matrices were processed with a proprietary jos-pe tanning developer that probably included pyrocathecin with soda, caustic soda or ammonia (willekens, 1926). the developer hardened the gelatin proportionally to the exposure to light and built up the necessary relief for printing. the unexposed areas (the non-hardened gelatin) would be removed under warm water (60 90º c). this method had already been described by leon warnerke in 1881, developed and applied by gustav koppmann in different patents, some of them under the name of the company jos-pe. the difference with non-relief processes was that there was no presence of gelatin in the white areas, which avoided dirty or blurry highlights. the jos-pe process in the jacob merkelbach collection at the rijksmuseum in amsterdam 20 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140102 to proceed with the printing process, each matrix was soaked in its corresponding jos-pe dye bath for 20 minutes for the first time and fewer minutes for the subsequent times. the dyes would be absorbed by the gelatin on the positive plate and remain in it until put in contact with a wet proprietary jos-pe paper. the dyes were sold in solid form but dissolved in water for this step. the manufacturer suggested using ammonia to dissolve the red dye in water. and citric acid was added to the blue and yellow dyes to facilitate the transfer of the dyes to the paper (jos-pe farbenfoto, patent no. de000000421244a, 1924). the printing matrices could be used several times to produce multiple copies of the same image, until the relief looked deteriorated. fig. 5. portret van mies rosenboom merkelbach, jacob merkelbach, 1920-1930. rp-f-f26748-1. rijksmuseum. here, the dyes transferred to the paper, in this manner forming the image there (fig. 5). users were recommended to start with the blue matrix and continue with either yellow or red. thanks to the transparency of the printing plates, the superposition of the three images was easy if compared with other color printing processes with opaque matrices. however, this step was difficult and it is common to observe misregistrations in the final prints. according to adrianus antonius marinus van rietschoten, a retoucher at the atelier merkelbach, a jos-pe print would take a week to be finished (veen et al., 2013). all the materials needed for the process were sold by the jos-pe company and distributed by licensed companies in different countries, for instance, jos-pe trade company color photo in arnhem, for the netherlands or ibero foto color in madrid, for spain. photographers interested in the process were kindly invited to attend workshops or events where the process was explained. most of the information collected on the process comes from the personal archive of the catalan amateur photographer mariano ricart, interested in color printing processes, kept at the institut de estudis fotogràfics de catalunya, in barcelona (burgués and belmonte, 2015) which includes numerous brochures, recipes, personal notes, study materials and correspondence between the photographer and the jos-pe farbenfoto company. another of the main sources for this research is the pamphlet published by willekens in 1926 where the process is described at the same time as it is commented. 6. characterization of the prints fortunately, the rijksmuseum collection includes a complete set of the negatives, the printing plates and the final print of a photograph by jacob merkelbach (fig. 4 and 5). this circumstance significantly aided our understanding of the process and gave us access to the original materials that could be analyzed for this research. under the microscope, jos-pe prints have a smooth continuous tone without any visible pattern. the dyes are shown in a soft tone, although sometimes individual particles are visible, perhaps due to their incomplete dissolution in water. also small spots can be observed, probably produced during the printing process, when small bubbles in the gelatin were broken during the transfer of the image. another characteristic is the retouching process carried out by the photographer in order to improve the final image. under specular light these corrections become visible, especially the ones created by scratching the surface of the print to make it lighter (fig. 6). retouching techniques also included adding media with a brush or with a pencil, to darken lighter areas or add details. all of the prints in the rijksmuseum collection have a matte surface, except one (rp-f-f03955) that shows a glossy coating on the surface. this coating did not fluoresce under uv irradiation, and no other analyses were carried the jos-pe process in the jacob merkelbach collection at the rijksmuseum in amsterdam 21 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140102 out during this research project, so it could not be identified at this time. fig. 6. retouching on a jos-pe print observed with specular light. rp-f-f03967. rijksmuseum. if the print is not trimmed, the superposition of the three colors can be observed at the borders. the pressure marks made by the edges of the glass printing plates during the printing process are also visible (fig. 7). fig. 7. border of a jos-pe print. microscopy image (x35). rp-f-f04010. rijksmuseum. 7. instrumental analysis to better identify the paper and media we used x-ray fluorescence analysis. the top layer of the support paper contains barium and sulfur, which indicates that the paper was coated with a baryta layer, used to isolate the fibers of the paper and create a white, uniform base for the image. fig. 8. cross section of a jos-pe paper. microscopy image (x700). thanks to the donation of a sample of jos-pe paper from richart’s archive from institut de estudis fotogràfics de catalunya (iefc, barcelona), we were able to perform a cross section. in this analysis we confirmed that the baryta layer had an extra top-coat of a thin gelatin layer, the image receiving layer (fig. 8). this structure is observed under the microscope, specially at the borders (fig. 9). fig. 9. border of a jos-pe print. microscopy image (x35). rp-f-f03960. rijksmuseum. the jos-pe process in the jacob merkelbach collection at the rijksmuseum in amsterdam 22 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140102 for the identification of the colorants we requested the expertise of art ness proaño at the rijksdienst voor het cultureel erfgoed (rce). the dyes were sampled from the three printing plates, extracted from the gelatin and identified with liquid chromatography (uplc). the red dye was identified as carmine (in ammonia), the blue dye was identified as indulin b or acid blue 20 (sulphonated) and the yellow dye was identified as dianil yellow 2ri (proaño and neevel, 2020). with this knowledge we proceeded to reconstruct the process in order to artificially light-fade mockups on paper to analyze the chemical stability of the dyes. the red sample was exposed for two, four and eight hours, and changes already became apparent in the first exposure period of two hours, indicating low lightfastness. the fading tests of the other two mockups have not been subjected to fading tests yet, however, the report from rce suggests that, based on specialized literature, the lightfastness of the blue dye is bws 4 and that of the yellow dye is 2-3. 8. conclusion this research shed light on this interesting process and its importance in the history of color photography. the jos-pe process, far from being a unique invention, benefitted from other inventions and patents. the basis of the printing system had already been described by leon warnerke, leon didier and gustav koppmann. the jos-pe camera was inspired by the ives camera from 1899. the three jos-pe dyes are common in the literature of dye imbibition processes and were also used in the pinatype. the jos-pe paper was a typical paper with a baryta layer and topcoat of gelatin. however, the jos-pe process made complex three-color photography available to a broader public, offering professional results to both amateurs and professional photographers. our research indicates that the dyes are not very stable, although more research has to be performed in difference circumstances. 9. conflict of interest declaration the author states that no actual or potential conflicts of interest exist including financial, personal or other relationships with other people or organizations within three years of beginning the submitted work that could inappropriately influence, or be perceived to influence, her work. 10. funding source declaration this research was made possible thanks to the gieskesstrijbis fonds. 11. acknowledgement i would like to thank my colleagues at the ateliergebouw in the rijksmuseum: idelette van leeuwen, rosina herrera, martin jürgens, dionysia christoforou and virginia morant, and other contributors to the research: art ness (rce, amsterdam), laia foix (iefc, barcelona), anneke van veen (stadsarchief, amsterdam), cristina durán (stadsarchief, amsterdam), caroline vincart and ann deckers (fomu, antwerp), sylvie pénichon (art institute, chicago), vanessa torres (science media museum, bradford). 12. short biography of the author laura covarsí zafrilla is an independent conservator specialized in photographic heritage. she received her m.a. in conservation from instituto politécnico de tomar, portugal, with an internship in the photographic archive of the maritime museum of barcelona (spain). she previously studied history of art (university of salamanca, spain) and photography (school of arts of huesca, spain). she worked for public and private collections in spain and at the rijksmuseum of amsterdam between 2017 and 2019, where this research was carried out. references burgués, a. and belmonte, a. (2015). el fondo personal de mariano ricart fontanet. barcelona: universidad de barcelona. facultad de biblioteconomía y documentación didier, l. (1908). manufacture of colored photographic images. us patent no. 885,453 friedman, j. (2010). history of color photography. milton keynes, uk: lightning source hegeman, h. and leijerzapf i. (1985). atelier j. merkelbach. available at: https://depthoffield.universiteitleiden.nl/0203f05nl/ (accessed: 11.2021) illera, m. and canova, a. (1927). ‘contestando a una carta de madrid’. el progreso fotográfico. n. 88. p. 29 31. ives, f.e. (1899). photographic camera. us patent no. 632,573 jos-pe farbenfoto. 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(2006). die deutsche photoindustrie. wer war wer. ein nachschlagewerk zur geschichte von über 1000 firmen der phototechnischen und photochemischen industrie in deutschland, sowie den wichtigsten personen in industrie und entwicklung. munich: selbstverlag. veen, a., geusau, s., banning, n., heuvel, m. and oort, t., (2013) fotostudio merkelbach 1913-1969. 1st ed. amsterdam: uitgeverij komma. wall, e., 1928. practical color photography. boston: american photographic pub. co. willekens, l.c.c. (1926). ‘het jos-pé kleurenprocédé’. fotografische bibliotheek, 11a. dordrecht: c. morks cz. 57 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130207b the red of lina and oscar luiza paes de barros camara de lucia betlramini 1 , paulo césar castral 1 1 institute of architecture and urbanism, university of são paulo, são carlos, brazil. luiza.beltramini@usp.br, pcastral@usp.br corresponding author: luiza paes de barros camara de lucia beltramini (luiza.beltramini@usp.br) abstract the article gives a brief history of modernist architects lina bo bardi and oscar niemeyer and tries, through a bibliographic review and visual analysis, to identify meanings, analyze the generated spatiality and understand the impact caused by the repetitive and striking use of the red color. to do so, a brief history of the color red and how it was mastered, perceived, and appropriated by humans over the centuries is traced, and, finally, three essential projects of each architect are analyzed. we conclude narratives for the reds of lina and oscar, who go through the communist history of the characters, visual indications, and the theory of functionalism. keywords modernism, brazilian modernism, red, oscar niemeyer, lina bo bardi received 23/03/2021; revised 12/08/2021; accepted 14/10/2021 the red of lina an oscar 58 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130207b 1. modern brazilian architecture according to lúcio costa (1902 –1998), modernism in brazil is justified by the affirmation of the identity of our culture and representing the "spirit of the time." for oba (2014), this movement, which prioritized function, caused brazilian architects much interest. the french-swiss architect le corbusier had a significant influence on the formation of modern thought in brazilian architects. the discussion about modern issues gained substantial prominence in brazil after the constant migratory movements in the post-war period, whether from brazilians who returned after studying abroad or from foreigners looking for an opportunity outside europe in crisis. it is important to note that not only did the european crisis repel professionals, but the condition of brazil attracted them. cavalcanti (2001 apud lobato, 2009) states that good economic conditions, the government's will to establish a new face for the federal capital, and a generation of revolutionary intellectuals and architects made modern brazilian architecture a reality. with the new republic, the change in the bases of production of national wealth and the migration of the status of brazil from an agrarian to an emerging country creates a demand for buildings that represent this recent phase of the country. these works were mainly from the government of getúlio vargas (1930-1945), which had as one of its priorities the construction of buildings to house government agencies of the new administration (cavalcanti 2001 cited lobato, 2009). among the various possibilities for discussing the use of color in this historical-cultural context, two brazilian architects were selected for a more careful look at this article due to the recognized influence in the unfolding of the issues opened by the avant-garde. the works analyzed, both three examples of lina bo bardi as three of oscar niemeyer have a marked cultural nature. in addition to the programs themselves, such a characteristic is manifested in the condition of manifestos about what architecture is, which this type of order allows. in this sense, party issues are displayed more clearly, making it possible to investigate the meanings of design actions and how the definition of red, present in all the works to be analyzed, contributes to the creation of the architectural discourse of each architect. 1.1. lina bo bardi the architect was born on 5 dec. 1914 in rome, italy. she graduated in architecture from the faculty of architecture of the university of rome. after graduating, she moved to milan, where, after working for gio ponti, she became the editor of the magazine quaderni di domus. during the second world war, she founded with bruno zaevi the publication a-cultura dela vita and is a member of the italian communist party. in 1946, she married the journalist and art critic pedro m. bardi (19091999), and, in that same year, they left for brazil, where she was naturalized in 1951. initially, she lived in rio de janeiro-rj, then the country's capital, where she had the opportunity to expand her influences and knowledge of the new country. however, when she moved to são paulo (sp) after pietro was invited to found and direct the museum of art of sao paulo assis chateaubriand masp lina turns icon of modern brazilian architecture. in 1950 lina founded habitat magazine an important cultural vehicle that included art, architecture, design, cinema, theater, music, photography. in 1951 she built her residence the glass house which is currently the headquarters of the instituto lina bo e p. m. bardi. in 1957 construction began on the new masp headquarters lina's first project that will be analyzed in the article in 1959, "she is invited by the governor of bahia to direct the museum of modern art of bahia (mam-ba)" (instituto bardi, 2020), in the same year she restores solar do unhão second project analyzed in the article. in 1977, the third project analyzed in this article began to be constructed the centro de lazer sesc fábrica pompéia in são paulo (sp). 1.2 oscar niemeyer oscar niemeyer was a brazilian, born in rio de janeirorj on 15 dec. 1907. he studied at the national school of fine arts (now the federal university of rio de janeiro). in his third year, he interns with lúcio costa a future urban planner responsible for the new national capital brasília (1960). lúcio costa was invited, in 1936, by the then minister of education gustavo capanema to design the new headquarters of the ministry of education and health. lúcio brings together a group of young architects; lúcio still insists that le corbusier be invited as a consultant. despite not inviting oscar from the beginning, he ends up calling him. in this way, oscar contributes to the project that is considered one of the foremost modern brazilian architectural landmarks, the gustavo capanema palace. after that, oscar falls in the graces of important figures as the best example, we have the governor of the state of minas gerais, brazil's future president and founder of brasilia, juscelino kubitschek. oscar lived 104 years and worked until the last years of his life, resulting in a vast collection of works, drawings, and sketches. in 2003, nine years before his death, he was asked to design his first building in britain as part of a serpentine gallery action devising the third work analyzed in this article. the red of lina an oscar 59 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130207b 2. the red according to michel pastoureau (2017), red was the first color that humans dominated, manufactured, reproduced, and discovered different tones, first in painting and later in the dye. according to the same author, this also explains why in some languages, the same word means "red,” "beautiful," and "colorful." le corbusier (serra llunch, 2013) agreed and guaranteed that red affirmed its presence. one of the primary colors is considered a warm color (argan, 1992) and has been widely used with mastery by great artists such as pietro mondrian, vassili kandinsky, marc chagal, ellsworth kelly, and mark rothko. outside the artistic field, the color red is also very representative. according to klein (2018), red has been a symbol of power and government since antiquity permeating the middle ages; it was worn by roman emperors, popes, and european sovereigns. during the french revolution, a movement that, according to some authors, inaugurates the contemporary age, the jacobins, and sans-culottes as identification dressed in a red cap. during the 20th century, the color red was adopted by communist movements, workers, and socialist movements, in the sense of fraternity. in this context, the color was also associated with the hope of a better life, as well as with blood and suffering. 2.1 museum of art of são paulo – são paulo, são paulo – brazil the museum of art of são paulo was founded in 1947 by assis chateaubriand (1892-1968), businessman and patron of são paulo. the first modern museum in the country was directed by the italian critic and dealer pietro maria bardi, lina's husband. initially, it worked on one floor of a business building and moved to the current location in 1968. the location of the building itself is iconic, situated on the most famous avenue in the country's financial capital; it is still under the intersection of another avenue. the landmark of the history of 20thcentury architecture is based on the use of concrete and glass. its 74-meter span has always been a geographical reference and meeting point. the four massive pillars that support the volume above this span and the beams that make up this structural effort are bright red. although, since the beginning of the sketches, the red color appeared and, according to miyoshi (2006), it was an old idea for lina to use the color, initially, the beams had no color; they were in apparent concrete without any aesthetic treatment. in the 1990s, to solve an infiltration problem, a company donated products "for the protection of exposed concrete against deterioration" (miyoshi, 2006, p. 143). the color chosen by lina is fire-fighter red (fig.1); in addition to transforming the building into a "cultural event" (miyoshi, 2006, p. 143), the proposal aimed to encourage the use of paints that fled white or ice accounted for 70% of national consumption (miyoshi, 2006). on the floors below the span, there are two stair-ramps also in red (fig.2). the proposal made by lina bo bardi, in this sense, reserves the use of red in two distinct functions, structure and circulation. the red elements bring common the desire to signal, point out, and distinguish the elements put in color. architecture should be understood as a set of elements articulated throughout but with their particularities. fig. 1 – masp, (kon, n.) fig. 2 – stair-ramps. (kon, n.) 2.2 the solar do unhão – salvador bahia, brazil upon receiving the invitation to direct the museum of modern art, lina stayed in salvador, bahia, between 1959 and 1964, where she found another face of brazilian identity, the african face. the museum is the red of lina an oscar 60 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130207b located in solar do unhão, an existing building that needed to be restored and adapted to receive such a program. due to her experience in post-world war ii italy, lina applies critical restoration to the set of buildings (cerávolo, 2010, p. 219). the use of the color red in the external frames (fig. 3) was not agreed with heritage agencies; cerávolo (2010) states that the colors of the facades and frames would be specified later after submission to the national heritage agency. finally, the choice of red color did not pass through the appreciation of organs responsible agencies; azevedo (1963 apud cerávolo, 2010, p. 234) characterizes this and other choices as a "loss for the monument." in the solar do unhão project, what can be perceived is the use of red as a signaling act with intentionality close to the use of color in the masp project. the architect with her choice reveals her look at the historical construction processes belonging to the work involved, the difference between the brick-built in masonry, and the openings treated in wood. by observing the set, one can learn the difference between the fixed parts and the moving parts, employing colors, enabling many other inferences about the architectural qualities. fig. 3. solar do unhão’s entrance. . (kon, n.) 2.3 sesc pompéia – são paulo, são paulo – brazil lina was invited in 1977 by renato requeixa and gláucia amaral, then directors of the sesc social service of commerce, to transform the mauser brothers' old drums factory into a leisure center. the project develops over nine years with the help of students and recent graduates (ferraz, 2008). the new public facility should promote social harmony, cultural production, and the social welfare of the city's population. with the addition of two large exposed concrete prisms to the original set, the project gained prominence, the blocks receiving sports equipment were inaugurated in 1986. the apertures of the lower block have an amoeboid form, while in the more massive block, they are square but do not follow orthogonal alignment. in both buildings, the openings are closed in red wooden trellis (fig. 4). in addition to the use of red in the frames, several installations, such as air ducts, truss fittings, handrails, throughout the complex, which a priori should go unnoticed, become red and stand out in the landscape. fig. 4. sport blocks sesc pompéia. (kon, n.) the sesc pompéia project reveals the coherence of the architect's plastic research. an intention in the sports blocks is very close to that seen at solar do unhão. despite different situations, the same desire is to signal and differentiate between fixed, open, and mobile openings. the amoeboid shape in one block, and the misalignment, in the other block reveals the constructive possibilities of concrete as much as the rhythm and alignment reveal the limits of masonry in the solar. 2.4 museum of contemporary art of niterói (mac), niterói, rio de janeiro – brazil the museum on the banks of guanabara bay in niterói was designed in collaboration with structural engineer bruno contarini. completed in 1996, the cylinder blooms like a flower composing the landscape for which it is also a viewpoint. its circular shape includes a large glass opening the red of lina an oscar 61 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130207b that allows visitors to the museum to appreciate all the natural beauty that surrounds it. with its main body at 16 meters high, access is via a winding concrete ramp that allows visitors to appreciate the landscape and the building itself on a 98-meter long architectural promenade full of changing perspectives. the invitation and marking of the ramp take place through its red fire floor, a plastic decision to highlight the access of the large white volume (fig. 5). fig. 5. museum of contemporary art (leonardo finotti in: segre, 2010) fig.6 main facade with access ramp – (modern architecture london) 2.5 serpentine gallery summer pavilion – london, united kingdom the serpentine gallery pavilion aims to give visibility to architects who do not yet have a project in the uk, so the talent of the professional can be shared and appreciated by a new audience strolling through hyde park. the pavilion is part of an annual event produced by the gallery that performs its assembly at the beginning of the london summer and is dismantled at the end of the same season (allen, 2018). for 21 years, this annual event has featured projects by great architects, and in 2003 it was oscar niemeyer's turn. with clear traces of modernism, it was "built-in concrete, painted white and accessed by a ramp" (doroteo, 2016). a synthesis of significant elements of the architect's bestknown projects, a grand gesture of drawing, loose from the terrain, unfolds in a single direction and generates the spatiality of the ensemble. this gesture is presented in white, being emphasized at the entrance by a void, built away from the closings, and accessed by a ramp with a red cover (fig 6), and at the back by a red plane. 2.6 auditorium – ibirapuera – são paulo, são paulo – brazil conceived by the then governor of the state of são paulo, josé pires do rio, the park that would be modeled after great european examples such as hyde park in london or boi de boulogne in paris. parque do ibirapuera occupies a total of 157,000 m² and was only opened in 1954 due to the drainage problem that the land presented. the problem was solved by the then official manequinho lopes, who decided to plant hundreds of australian eucalyptus on the ground to drain the water in the region. fig.7. ibirapuera auditorium (kon, n.) oscar niemeyer designed the buildings that make up the park's infrastructure, and burle marx should run landscaping, but the latter was not executed. the park's program has various equipment such as temporary exhibition spaces, museums, auditoriums, lakes, and planetariums. despite the vast program here, we will analyze only the auditorium. initially, the building was not completed and was only completed in 2005, almost 50 years after the park opened. the auditorium is a trapezoid with its entrance marked by a red marquee (fig.7), the red of lina an oscar 62 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130207b nicknamed flint (dudeque, 2009). in addition to the punctual presence at the entrance, the back of the auditorium (which is reversible) (fig. 8), the large opening door of the stage is also a large red rectangle that strongly marks the white prism. fig.8. ibirapuera auditorium back door (kon, n.) oscar niemeyer adopts a very controlled color/material palette that uses only white, red, and wood. white is reserved for opaque surfaces built, while the wood is for the handrail and some acoustic coverings. red is highlighted not for a specific function but for accompanying the user/spectator through their experience in the auditorium spaces. first, it signals the entrance unequivocally with the marquee and immediately welcomes the route along the internal ramp (fig. 9) to the audience spaces through the floor covering. it would be a matter of signaling, as in the previous cases. however, the experiential issue is highlighted when it is emphasized when inviting tomie otake to make a sculpture in red. the artist's occupation of the wall and ceiling radiate throughout the space through the reflection of color. red expands its signaling and didactic function to become the poetic accent of the proposal. fig.9. intern ramp – ibirapuera auditorium (kon, n.) 3. conclusion the secure connection of the two architects, lina and oscar, with the premise of modern architecture remained faithful to the attention to the functionalism typical of the avant-garde of the beginning of the 20th century. the red of lina and oscar may have had different origins; they are in sympathy with communism and in the certainty of marking their projects with vivid and exquisite colors. kandinsky's theories fostered this avant-garde by attributing spiritual qualities to very few geometric elements and colors; for him, for example, "red is extremely immobile by a restless color, vivacious and active ... immense and almost inconsequential force" (luz, 2014, p.214). the perceptual intensity of the red is adopted by the two architects, analyzed here, as a cognitive resource to signal what architecture is built on. lina bo bardi's case, with a strong emphasis on the tectonic issues of the work in its plastic dimension through a didactic approach, is one of the ways she found of forming the critical conscience of modern man. in the case of oscar niemeyer, this social function emphasizes this social awareness due to its poetic dimension through the valorization of the experience of color. the two architects fixed themselves in the collective imagination as irreverent, bold, and brilliant; undoubtedly, they pictorially red-marked both histories. 4. conflict of interest declaration the authors declare that nothing affected their objectivity or independence and original work. therefore, no conflict of interest exists. 5. funding source declaration this research did not receive any specific grant from funding agencies in the public, commercial, or not-forprofit sectors. 6. short biography of the author(s) luiza beltramini master's student at the institute of architecture and urbanism at the university of são paulo, a researcher at n.elac, research support center for language studies in architecture and city. graduated in interior design (ifpb) and architecture and urbanism (ufpb), she is currently researching aspects of spatial design and perception, emphasizing the promenade architecturale. paulo césar castral ph.d. professor at the institute of architecture and urbanism of the university of são the red of lina an oscar 63 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130207b paulo, research group on language studies in architecture and city (n.elac) coordinator, is responsible for the research line perception of architecture and the city. holds a doctorate in multimedia (unicamp), a master's degree in architecture and urbanism (eesc/usp), and a degree in architecture and urbanism (eesc/usp). references allen, k. 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(accessed: 17 feb. 2020). 13 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130202 a didactics of colour based on an innovative educational approach at the hochschule für gestaltung in ulm anna poli 1 1 department of human sciences for education, università degli studi di milano-bicocca, italy, annamaria.poli@unimib.it abstract tomás maldonado held the posts of lecturer and rector at the famous hochschule für gestaltung in ulm from 1954 until 1967-68. his foundational contribution to the field of education/training dates to his thirteen years at this school, where he concentrated his theoretical and practical inquiry on developing a new approach to the teaching of key design-related subjects. while at ulm, maldonado became keenly interested in devising an innovative new teaching method based on the notion of “cooperation among disciplines”. this principle guided him throughout his lengthy teaching career, as he enriched and refined his educational thinking and developed increasingly effective teaching methods for the disciplines he taught. there was something important and revolutionary about his teaching approach and his method also became well known in italy. even earlier, as a very young artist in argentina, where he helped to found the concrete art movement, he had displayed and constantly shared with others an “almost obsessive preoccupation” as he himself defined it, with actively contributing to a total vision of culture. towards the end of his life, he characterized this project as “over-ambitious". however, it showed that he was interested in crossdisciplinarity from the outset. crossdisciplinarity, or the “third culture”, as he himself called it and understood as the attempt to overcome the dichotomy between “hard” and “soft” sciences. in light of this background, i set out here to examine tomás maldonado’s approach to developing new teaching methods for his classes, especially in relation to the theme of colour as an integral part of his course in visual methods. keywords: didactics of colour, tomás maldonado, visual education, visual methods, scientific approach to visual culture, interdisciplinarity, transdisciplinarity, hochschule für gestaltung in ulm, received 15/01/2020; revised 25/10/2020; accepted 07/04/2021 mailto:annamaria.poli@unimib.it a didactics of colour based on an innovative educational approach at the hochschule für gestaltung in ulm 14 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130202 1. introduction tomás maldonado held positions as a lecturer, and later rector, at the famous hochschule für gestaltung in ulm (germany) between 1954 and 1967-68. in this paper, i offer an analysis based on my personal acquaintance with tomás maldonado and my knowledge of his studies and his works of his teaching methods and especially the “didactics of colour” that he devised for his course in visual methods. i was stimulated to document his teaching of (and with) colour by our shared interest in certain themes. one interest that we had in common was a passion for colour and how it is perceived, topics that we often discussed, and which for maldonado were the object of meticulous study, enriched by his wideranging inquiry into the culture and science of colour. here, i document some extraordinary interdisciplinary and transdisciplinary exercises he designed and implemented with his students during his years on the academic staff of the foundation course in design at the hochschule für gestaltung in ulm. his interest in teaching and training, which he later continued to pursue in other universities around the world, first developed during his time in ulm. over these thirteen years, maldonado focused his theoretical and practical inquiry on developing a new perspective on teaching particular subjects, both to students of design and to those pursuing other branches of study. 2. who was tomás maldonado? "[...] although i was not very young when i arrived in ulm, i was thirty-two and [had previously enjoyed] a short but intense career as an artist in argentina, i acknowledge that the [ulm] experience played a decisive part in my formation. it contributed to considerably broadening my intellectual horizons… i am especially alluding here to my theoretical (and practical) engagement with industrial design and communications. at the same time, it was in this very setting that i developed an interest in semiotics, the philosophy of science and technology and, last but not least, the sociology of communications. a crucial role in all of this was played by the educational challenge, the need to prove myself every day in my teaching. suddenly i discovered within myself a passion that would remain a constant throughout the rest of my life; a passion for making myself useful in the intellectual (and professional) training of young people. […]” (maldonado 2010, p. 29) tomás maldonado arrived in ulm in 1954 at the invitation of max bill, a well-known exponent of the concrete art movement in switzerland. the academic staff at the german design school was composed of internationally recognized figures from all over the world. during his years at the ulm school, maldonado was appointed lethaby lecturer at the royal college of arts in london in 1965, fellow of the council of humanities at princeton university in 1966 and lecturer at princeton’s school of architecture from 1968 to 1970. in 1979, he was research fellow at the graduate school of design at harvard university and gave numerous lectures at other universities in the united states and around the world. in the 1970s, he moved to italy; first to the university of bologna from 1971 to 1984, where he taught on the degree course in music and the performing arts offered by the arts and philosophy faculty, and subsequently at milano politecnico, where he was based at the faculty of architecture from 1985 to 1997 and taught on the degree course in industrial design he himself set up in 1993. he also taught at the faculty of architecture in venice (iuav). his itinerant teaching work across europe, the americas, and beyond fuelled his constant and impactful passion for the formation of generations upon generations of students, who subsequently became expert professionals in multiple fields and who today are scattered all over the world (chiapponi 2018). 3. the role of hfg in generating a new design culture the hochschule für gestaltung in ulm was founded to be an international experimental centre dedicated to theory, research, and development in the domain of industrial design (https://roericht.net/hfg-synopse/aufbau). lindinger wrote in the catalogue of the ulm school exhibition that the ideas that sprang up there were “a message destined to the whole world”. a more than reasonable statement, given the international composition of the school’s academic staff and its stated educational mission, that of teaching an innovative approach to design during the post-world war ii reconstruction period (lindinger 1988). although its existence was brief, the hfg in ulm is still today viewed as one of the leading design schools of the twentieth century: it was founded in 1953 and closed down in 1968. beginning in 1954, tomás maldonado https://roericht.net/hfg-synopse/aufbau a didactics of colour based on an innovative educational approach at the hochschule für gestaltung in ulm 15 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130202 contributed to defining the school’s curriculum and subsequently also to devising a new and robust method of training designers. kenneth frampton stated in an interview that: “hfg was undoubtedly the most important school of design founded after the second world war, not because of what it accomplished in terms of actual production nor because of the large number of designers who actually qualified there, but ultimately on account of the extraordinary level of critical awareness that it managed to sustain in its everyday work [...]” (frampton 1974; lindinger 1988). the curriculum was initially divided into four streams: product design, visual communication, construction, information, with the addition, at a later stage, of film. it offered a four-year course of studies, at the end of which students were awarded a diploma. the course was structured as follows: in the first year, all students were required to take the foundation course, before going on to specialize in one of the areas just listed for the remaining three years. the hfg was officially inaugurated on 02 october 1955. max bill was rector initially, from 1955 to 1956, while six months later, in march 1956, a council of rectors was set up to run the school, a group that initially comprised the following members of the academic staff: otl aicher, max bill, gugelot, tomás maldonado, and vordembergegildewart (escot 2002). the hfg, like the bauhaus, offered a preparatory year known as the foundation course (grundlehre), designed by max bill, to introduce the students to the various career paths within design. part of the first-year curriculum was devoted to the fundamental principles of design or basic design, a term coined by josef albers, based on the course that he had delivered at the bauhaus, at black mountain college in asheville in 1933, and finally at yale university (huff 2009). in 2002, günter hörmann and martin krampen came to milano, and interviewed tomás maldonado about his experience at ulm. on that occasion, he spoke about the challenging historical period and the difficult decisions to be made when he first came to teach at the hfg, especially in relation to teaching methods, given the school’s goal of developing an innovative didactic approach: “[…] the issue was whether to continue the tradition of the bauhaus or to distance ourselves from it. we chose to distance ourselves from the bauhaus. that meant that we wanted to revisit traditional bauhaus themes in light of the newly emerging circumstances of that given historical period, it was the post-wwii era in a germany in need of reconstruction”. maldonado laid particular emphasis on the hfg’s revisiting of certain bauhaus themes in the context of its foundation course. to cite his own words during the interview: “[…] the idea was to change approach, or rather, to identify a different approach, trying to permeate it with, to make it sensitive, receptive to scientific developments, and to mathematical and methodological studies with a bearing on what was actually needed to engage in design. so, it was a question of inheriting the ideas of the formal [bauhaus] methodology, but adopting a highly mathematicized approach that was beginning to come to the fore at that time in the domains of problem solving and decision making these were techniques that could be immediately applied to the field of design […]" (hörmann and krampen 2002). some years after this interview, in 2009 to be exact, tomás maldonado spoke, during a talk delivered in weimar at the festakt zum 90. gründungsjubiläum des bauhauses, about his “[…] lively exchange of letters with walter gropius […]” on some of his [maldonado’s] theories concerning “[…] the need to take on board the elements of continuity and discontinuity in the ulm project with respect to the bauhaus project […]”. in this regard, he stated that: “i am personally more and more convinced that it is time to recognize without nostalgia, without any pretence of regret, that the bauhaus, as an institutional model, has ceased to be relevant, for the simple reason that it is no longer equipped to provide appropriate responses to the pressing needs of our time […]" (maldonado 2009). on the other hand, in relation to how the legacy of the bauhaus contributed to the ulm school’s approach to teaching design, we should note another memorable statement of maldonado’s concerning the merits of the bauhaus school: “[…] the reason that i remain deeply attached to the bauhaus, still today, is not the thousand small and big achievements that are usually attributed to it, but rather the great lesson that the leaders of the bauhaus – the ‘bauhäusler’ – passed on to us as their legacy. that is to say, the fundamental desire to seek out and to provide, by every possible means, socially and culturally innovative responses to the needs of the historical phase we have been destined to live in” (maldonado 1963; 2009). 4. a new teaching methodology thus, tomás maldonado’s keen interest in the field of education emerged at the time that the hfg was being founded in ulm. he particularly focused his thinking on devising an innovate educational approach based on “cooperation among disciplines". a teaching method developed for the students at ulm, the future designers of a didactics of colour based on an innovative educational approach at the hochschule für gestaltung in ulm 16 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130202 the third industrial revolution, and for all those still keenly interested in revisiting aspects of the bauhaus approach to teaching design, on which max bill had originally based the hfg’s courses. in maldonado’s view, such aspects of the bauhaus approach were no longer suited to the needs of the hfg in ulm. the first-year foundation course at the hfg had four stated objectives: “1. it introduced students to the activities of the different streams of the curriclum, and especially the methods in which these activities were grounded; 2. it familiarized the students with key issues in [contemporary] technological culture, thus informing them about the broader context framing specific design tasks; 3. it trained students in collaboration with other disciplines, thus preparing them to work on teams, or groups of specialists, in which it was crucial for each individual to understand the issues and perspectives of the other members; 4. it set out to rebalance differences in prior knowledge among students who not only had previously pursued different academic specializations but also came from different countries with different education systems.” (lindinger 1988, p. 45). in 1955, when maldonado took over responsibility for the foundation course at the hfg, he attempted to modify the didactic approach of the previous year, that of the foundation course directed by max bill which was in keeping with the vorkurs developed by albers at the bauhaus. maldonado was a great admirer of josef albers, and especially of one part of his course. he wrote that albers had taken on a very difficult challenge in devising the bauhaus approach to teaching design and that he had risen brilliantly to meet this challenge by transforming a set of diverse, and partially conflicting, compoments such as pedagogical activism, mystical expressionism, and an exasperated version of constructivism into a functional and coherent teaching model (maldonado 1963, p. 12). hence maldonado took the latest didactic approach developed by albers for the vorkurs into account when formulating the hfg foundation course, but only maintained selected themes, namely those relating to the theories of gestalt psychology, with a view to providing in-depth background to his exercises in visual perception (huff 2009, p. 107). he set out to adapt the other themes to meet the new requirements for training students in design, with the goal of formulating a teaching approach that would be more consistent and in keeping with "technocratic-positivist ideology (the mathematization of the design process, and the shift towards “operational research” models”). thus, maldonado embarked on a structural and concepual reform of the bauhaus didactic model which he essentially saw as obsolete (wick 1993, p. 285-286). his ultimate aim was to rethink the profile of the industrial designer in the post-war era and above all to design an educational trajectory for designers that would be more in line with the changes then underway in the industrial and production sectors. he believed that this could be achieved by improving the didactic approach and contents of courses for designers, chiefly by adopting a method that was scientific, exploited the benefits of technology, and was interdisciplinary. his educational strategy was focused on progressively enhancing learning based on "cooperation among disciplines”, a guiding principle that was to inform his entire academic career as a teacher and researcher in the field of education (maldonado 1963, p. 12; neves and rocha, 2013). in one of his last books, he stated that: “[…] interdisciplinarity and transdiciplinarity not only respond to an increasingly urgent need for cooperation among disciplines, but are also (and always have been) the expression of an inescapable universal vocation to knowledge. […]” (maldonado 2010, p. 11). fig. 1. – tomás maldonado, teaching at the hfg ulm, 1958, source: photograph by wolfgang siol, © hfg-archiv/museum ulm. tomás maldonado was almost obsessively preoccupied by the desire to actively contribute to a total vision of culture, which he had counted among his intellectual goals since he was a young artist helping to found the concrete art movement in argentina. this was a project that towards the end of his life he characterized as “over-ambitious", but which was already present when he was a young artist, forshadowing his later keen interest in crossdisciplinarity or, as he himself preferred to call it, the “third culture”, which he a didactics of colour based on an innovative educational approach at the hochschule für gestaltung in ulm 17 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130202 understood as an attempt to overcome the dichotomy between “hard” and “soft” sciences (maldonado 2010, p. 9). therefore, coming back to the teaching of design in ulm, from 1954/55 onwards, a new groundbreaking approach began to take shape, thanks to the crucial contributions of tomás maldonado and other lecturers invited to teach at the hfg. the change prompted by this novel approach, as mentioned earlier, not only impacted on schools of design and applied art around the world, but also on art academies, universities, and even other educational and training settings and institutions. the ulm model, defined as a new approach to teaching design that combined formal, theoretical, and practical instruction with working for industrial partners on so-called ‘development teams’ directed by members of the hfg academic staff, would be introduced in various other schools around the world in the years spanning 1960 and 1962 (lindinger 1988). in relation to the international spread of the hfg approach, kenneth frampton recounted in a 1974 interview that: “the questions that the hoschschule für gestaltung was asking itself ten years ago, are now consciously or unconsciously being posed by all schools of design and architecture, and the hochschule’s crisis of identity has become a universal malaise” (frampton 1974; lindinger 1988). in light of these developments and due to some disagreements with max bill, tomás maldonado, viewed as the theoretician behind the hfg’s founding principles, left the school and germany in june 1967, heading initially for princeton in the united states before moving to italy in the 1970s. when maldonado began teaching in italian universites, first at the dams in bologna and later at milano politecnico, he was immediately popular with students. his extraordinary capacity for study and his deep and lively intellect both contributed to his charismatic style of communication in the classroom. he was also a talented storyteller. a particularly exceptional aspect of his teaching was how effectively he was able to convey his knowledge to his classes of students. his intellectual generosity was amazing, and he was skilled at offering countless perspectives on any given topic. it came naturally to his listeners to allow themselves to be guided through a process of active cooperation and reciprocal exchange among the many disciplines that only maldonado was able to draw together so masterfully. the outcome was generally a hugh enrichment and broadening of his students’ collective knowledge base, along with a continuous flow of intellectual stimuli that inevitably gave rise to a pleasant, creative, and fertile “contamination” of the thinking of each individual student. his teaching was encyclopaedic in nature, and his method was based on active learning strategies informed by constructivist theories, which entailed the cooperative co-construction of knowledge with his students, whom he would invite to give seminars in the classroom. in sum, his method was new, stimulating, important, and revolutionary in its time. it was italy’s good fortune that he came here and formed many generations of students in this country also. 5. tomás maldonado’s influence on the teaching of design maldonado’s artistic experience as a student at the escuela de bellas artes manuel belgrano in buenos aires up to 1941 and his involvement in the concrete art movement that he helped to found, shaped his artistic journey, which underwent a number of key changes. his classical figurative art training was reflected in his earliest paintings, which were dark and monotonous in character. almost concurrently with this brief initial phase he began experimenting with abstract art. this shift is documented by works published inside and on the front cover of the first and only edition of the magazine “arturo”, which maldonado produced in 1944 with his first wife lidy prati and a group of other artists from the argentinian concrete art milieu. after this, maldonado entered a full-blown experimental phase as an exponent of concretism (escot, 2007). in embracing this new dimension of art, he was influenced on the one hand by constructivism and the avant-garde and on the other by his encounter in 1948 with european members of the concrete art movement: georges vantongerloo in paris and max bill in zurich. his trip to europe and these contacts helped him to reinforce and consolidate his thinking about the role of theoretical assumptions in concrete art. the themes he explored in depth at this time included the objectives of the process of generating a work of art, the deployment of techical and operational strategies, and the consumption of the final work of art (garcía 2010, pp. 105-109). when he returned to buenos aires, his art began to display a different compositional syntax: within the space of his paintings, he now used “more delicate” lines and geometric patterns with “weighted” chromatic interactions, yielding sophisticated compositions underpinned by unconventional visual-perceptual equilibriums and novel aesthetic relationships. beginning in the early 1950s, maldonado’s art – and his underlying approach to the creative process and to constructing his compositions – began to display the sign of further change: some of his works were now clearly based on the application of scientific methods and mathematical calculations, the basic principles of concrete art. a didactics of colour based on an innovative educational approach at the hochschule für gestaltung in ulm 18 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130202 maldonado’s keen interest in applying scientific theory and mathematical rigour to his art soon became his key focus. this focus also played a key part in his subsequent choices: the contents he taught at ulm were partly informed by new studies in the scientific domain which he systematically encountered in the course of his inquiry, as was his ongoing interest in concrete art (neves and rocha, 2013). in fact, as willam huff recounted in an essay for the catalogue of an exhibition on tomás maldonado, when he was put in charge of the foundation course in 1955/56, he introduced a strong "dose of concrete art" into the curriculum, which included two topics from the field of geometry: the theory of symmetry and the visual topology (huff 2009, p. 108). an in-depth account of this intermingling of concrete art and the contents of basic exercises in design was provided by marcel herbst, who clarified that while some works by concrete art artists were not intended to follow rules, many others were based on rules, especially those of richard paul lohse and max bill, because they were based on problems to be solved and mathematical calculations and could therefore easily be used as exercises in the context of a basic design course (herbst 2017). in 1988, to mark an exhibition on the hfg in ulm that was held in the city of genoa, tomás maldonado wrote: "[...] it is not true that the ulm school's theoretical framework was exclusively the outcome of our internal debate about the bauhaus. what is more: i am convinced that outside of that debate there were disciplines and currents of thought that exerted an influence that was decisive in some regards for our understanding of design and how to teach it. it must be remembered that our curiosity was boundless, in those years, towards all that was new or seemed to be new. a feverish, greedy curiosity that was particularly attracted by certain disciplines that were just beginning to emerge at that time: cybernetics, information theory, systems theory, semiotics, ergonomics. but also, and in no lesser proportion, by other more consolidated disciplines such as the philosophy of science and mathematical logic. the impetus for our curiosity, studies, and theoretical struggles came from our desire to provide a solid methodological basis for design work (lindinger 1988). hence the foundation course headed by maldonado underwent key changes that entailed the introduction of interdisciplinary theories, systematic analyses, and practical experience, thereby contributing to shaping the hfg’s offering to students of the new design. this development went hand in hand with a restructured curriculum, whose composition over the four-year duration of the course, as shown in fig. 2, gradually progressed from mainly basic training in non-applied design in the first year to mainly applied design subjects in the fourth (campos, roldán, sánchez moya 2015). the innovative didactic approach that maldonado brought to ulm did not just concern the new disciplines introduced into the foundation course or the contents of his own visual methods module (introduction to visual education), but subsequently also the introduction of other disciplines as part of new courses that were to further modify the hfg curriculum. furthermore in 1958, maldonado also proposed publishing a school journal, the hfg journal ulm, as a vehicle for presenting and disseminating the ideas developed at the hfg and the students’ work to a community of designers, academics, and other professionals around the world. fig. 2. – the curricular model developed by tomás maldonado for the hfg at ulm (lindinger 1988). 6. tomás maldonado: courses and teaching methods hence, from the early years of the hfg, tomás maldonado was actively involved in teaching courses there: in 1954, he was an assistant lecturer on the foundation course (grundlehre) headed by max bill, while in autumn 1955 and up until 1967 he became a full lecturer. the academic programs from those years document that in 1955, tomás maldonado taught visual methods to the first-year students taking the foundation course (grundlehre). beginning in 1958, he also taught a course in semiotics to the second and third year students in the visual communication and information streams, while in 1966/67 he taught theory of design to second year students of product design (lindinger 1988, pp. 280-282). hence, maldonado’s interest and disciplined enthusiasm in those years were channelled into meeting the need for innovation in the teaching of design. but what constituted an innovative approach to teaching design in that era? a didactics of colour based on an innovative educational approach at the hochschule für gestaltung in ulm 19 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130202 maldonado believed that learning could be strengthened by leveraging knowledge from different disciplinary fields via interdisciplinary and transdisciplinary work. his own innovative teaching was informed by scientific research and the analysis of statistical data (leopold 2013). giovanni anceschi, one of maldonado’s students at the hfg, wrote in an article about the foundational nature of basic design: “[…] which means claiming that the act of giving shape must be tackled using logical-conceptual and scientific instruments, and also means bringing design inside, and up the level of, the ‘connective tissue’ of the sciences […]” (anceschi 1983, p. 21). hence, maldonado’s focus as a teacher was on defining an experimental teaching model for the foundation course in design, which was to include some of the themes covered in josef albers’ basic design course, but would also be based on maldonado’s own intense quest to incorporate the scientific method, with the utimate aim of teaching design in such a way as to lay the ground for students to learn different modes and techniques of representation. he also introduced systems thinking, which he applied to many of the topics that he taught at the hfg, and which enabled him to devise extremely impactful learning experiments (aydemir 2018). indeed, in relation to his approach to teaching depiction/representation at the hfg, maldonado emphasized in his interview with hörmann and krampen that “[…] depicting has nothing to do with representation and so it was important to teach, those who needed to learn representation, a different way of going about it […]” (hörmann and krampen 2002). he would begin his classes by providing a theoretical introduction, followed by analytical exercises: bidimensional and tridimensional exercises and studies for applied design, to be conducted using visual representation tools and techniques. in his book reale e virtuale, published in 1992, maldonado wrote, in relation to the auxiliary resources used in design (models, exercises, graphs, etc.), that: “[…] you do not design or communicate with elaborate three-dimensional representations only, but also with twodimensional ones that are produced spontaneously, which are intuitive in relation to a problem needing to be solved [...]. but drawing, especially drawing to design is a type of modeling that, as we are taught by contemporary cognitivist psychology, raises a series of issues that are far from trivial. because drawing to accomplish design simultaneously takes the form of drawing while designing and designing while drawing. and this interactive coexistence between the means (drawing) and the end (designing) enables progress towards or outright identification of the desired solution.” (maldonado 1992, p. 102). maldonado’s visual methods classes were based on active learning techniques, serving to prepare students for subsequent visual training that would be interdisciplinary and crossdisciplinary, drawing on constructivist and connectionist theories among others. the practical bidimensional and tridimensional exercises were carried out using traditional visual representation tools and techniques. drawings were produced manually, in order to stimulate the brain hand-eye coordination with an extraordinary care and precision demanded. the point of the exercises was to guide the students, in a way that was supportive but rigorously non-directive, towards solving scientifically formulated problems in a systematic and self-directed manner. in a study on learning from educational experiments, ayse zeynep aydemir at the mef university di istanbul, defined the experimental educational activitiy conducted at the hfg and specifically tomás maldonado’s systemsthinking approach as based on a technique known as “scalelessness”. this term describes a work method whereby details and concepts are first presented on a small scale and subsequently translated into a design process, but also revisited to make changes. the timeline in fig. 3 illustrates the deployment of the five categories of educational experiment defined by aydemir in design schools across the world. these categories are participation, systematicity, complexity, linearity, and simultaneity. among them, it is interesting to note that experiments based on systematicity first appeared in the early 1950s, which is precisely when the hfg was founded in ulm. tomás maldonado’s classes in visual methods required his students to engage in sophisticated exercises in design. from the outset, he himself devised and set these exercises, with a view to guiding the students towards meaningful, reflexive, and mindful learning outcomes. all possible resources, including instruments, materials and techniques, were made available to the students, who were assigned the task of solving problems using geometric formulas or mathematical calculations. these practical exercises were systematically supplemented by moments of collective and individual reflection, as well as by discussion of the strategies that individual students had deployed to define their personal solutions. the approach just outlined is confirmed by the written testimonies of william huff and gui bonsiepe, both of whom took maldonado’s foundation course as students. a didactics of colour based on an innovative educational approach at the hochschule für gestaltung in ulm 20 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130202 fig. 3. – the graph shows the majority of educational experiments conducted in design schools, divided into five categories and arranged along a timeline from 1933 to 1990 (aydemir 2018). gui bonsiepe, who went from being a student to teacher, first at the department of product design and after at visual communication from 1961 to 1968. he recounted that maldonado, who had taken over responsibility for the first year of the hfg course in 1955, would began his course with the in-depth analysis of a set of exercises, also incorporating the required mathematical background and gestalt psychology into these classes. bonsiepe also stated that: “the foundation course exercises were also designed to develop the students’ aesthetic abilities and were described as non-applied exercises in design, to distinguish them from the applied exercises in solving practical problems to which the subsequent years of the course were devoted” (bonsiepe 2019, p. 126). the summary table in fig. 4 below is a key educational and historically valuable document that is held in the hfg-archiv/museum ulm. it sums up the themes and a set of exercises that maldonado devised for the firstyear foundation course students taking his visual methods module. william huff, also a student of maldonado’s and later himself a teacher on the foundation course at the hfg in 1963 and 1965-1968, wrote that tomás maldonado’s foundation course included ten practical exercises, whose original german titles invented by maldonado are reported in brackets: 1. sierpinski’s surface (sierpinskifläche); 2. peano’s surface (peanofläche); 3. weierstrass curve (weierstrasskurve); 4. black as a colour (schwarz als farbe); 5. symmetries (symmetrien); 6. exact non-exact (genau-ungenau); 7. non-exact exact (ungenau-genau); 8. perception of space (räumliche wirkung); 9. equilibrium of three surfaces (gleichgewicht dreier flächen); 10. interferences (störung). he further added that “for the three-dimensional exercises, it was necessary to also take classes in finite mathematics, the theory of symmetry, groups theory, and visual topology" (huff 2009, p. 111; bonsiepe 2019, pp. 141-142). in addition to these first ten exercises, maldonado devised others for the students of visual methods in 1956-57 and over the following years (huff 2009, pp. 111-112; neves and rocha 2013). most of these exercises included the use of colour in the form of a single hue or gradient, depending on the solutions that were sought/found in fulfilment of the task set by maldonado. this meant, as earlier mentioned, that the students were required to complete the exercises manually with traditional drawing equipment because computer technology was not yet available to them. nevertheless, maldonado was already speaking to the students about cybernetics (founded by norbert winner in 1947), complex systems theory, computational calculus, information theory, and the theory of signs. the first exercises that required the use of colour by applying the laws of geometry and mathematical calculation included the peano/hilbert curve and sierspinki surface, both key elements in the development of fractal objects as studied by benoϊt mandelbrot (lindinger 1988, p. 47). a didactics of colour based on an innovative educational approach at the hochschule für gestaltung in ulm 21 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130202 fig. 4. – chart showing the themes of the exercises assigned to the students attending tomás maldonado’s visual methods course in 1955/56, source: hfg-archiv/museum ulm. the following are the english translations of the titles of six of these exercises (numbered from 0 to 5): 0. sierpinski’s surface (spinsky dreiecke or sierpinskifläche); 1. peano’s surface (peanofläche); 2. weierstrass curve (system weierstrass or weierstrasskurve); 3. black as a colour (schwarz als farbe); 4. symmetries (symmetrien); 5. exact non-exact (genauigkeit ungenau). if we now go about analyzing these exercises, which were part of the foundation course common to all four design curricula offered by the hfg, we can clearly identify the interdisciplinary and crossdisciplinary approach that maldonado worked so hard to achieve. the even more interesting aspect of these exercises is the mathematical-scientific component leveraged by maldonado to initiate the students into learning about the use of colour and the value of colour visual perception with and without colour. in stressing the importance of knowing how to use geometry, while observing that not all designers are equally competent in this regard, william huff described how maldonado used to introduce his tutorials: “[…] tomás maldonado applied the formula of semiologist charles morris to his explanations of design, likening design, or at least applied design, to language. indeed, both possess the same three basic components: the syntactic component, the semantic component, and the pragmatic component: that is to say, structure, meaning, and function. differently to applied design, which is essentially linked to architecture, graphic design, and industrial design, basic design is purely concerned with the syntactic component or ‘structure’. now, ‘structure’ may be defined as the ‘organization of different parts’. two terms, therefore: ‘parts’ (or ‘elements’) and ‘organization’ (or ‘relationship’). system and structure are interchangeable in practice, albeit that the former evokes a notion of dynamism and the latter a notion of staticity. in mathematical language, which constitutes a special way of describing structures, we use the terms ‘members’ and ‘operations’ [huff 1984, pp. 36-37). hence, some of the exercises that maldonado assigned to his students displayed a key characteristic which consisted in the fact that the repeated component, once defined, would generate a particular kind of image (neves and rocha 2013). in this way, maldonado taught his students how to explore the relationships among, and organization of, the components of a structure (the overall image, the whole) and how to explore a structure composed of individual elements. a didactics of colour based on an innovative educational approach at the hochschule für gestaltung in ulm 22 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130202 in his exercises, he used colour to identify any of the three compoments of the language of design listed above by william huff. depending on the exercise assigned, colour could be used as a syntactic component, that is, as an element communicating the structure of a figure/image. or colour might be used to highlight the element making up a structure (form). or, finally, as a component that was pragmatic and functional to the message that was to be conveyed (function). colour was thus understood to be a variable within the system of signs or signals with which information may be communicated and visually encoded. to better exemplify how these exercises were executed in practice, the next figures display the products of four actual practical assignments carried out by three of maldonado’s students (fig. 5 6 7 and 8): dominique gillard and william huff in 1955-56 and urs beautler in 1956-57. the images in fig. 5 reproduce an execution by the student dominique gillard, of exercise no. 1, entitled “sierpinski’s surface” (sierpinskifläche). maldonado used this exercise to introduce students to the theme of the relationship between full spaces and empty spaces; and to how these spaces are visually perceived and understood by the observer when four shades of the same chromatic hue are used to make explicit the functions of full versus empty space. thus, in the example shown, each set of same-sized triangles was assigned one of the four shades of blue (from the smallest to the biggest and vice versa). the different patterns thus created provide the observer with a perception of the different triangles as empty spaces or full spaces, depending on how the shades of colour were arranged. the task assigned to the students was to construct a geometrically derived surface by applying the mathematical formula for sierpinki’s triangle, invented as its name suggests by waclaw sierpinki in 1915. construction of this figure begins with an equilateral triangle, whose internal space is divided into four equal parts so as to generate four smaller equilateral triangles. this operation can be iterated recursively such that each new triangle can generate four more and so on. the choice of sierpinki’s triangle for this exercise is intended to pave the way for interdisciplinary teaching/learning: it is a fractal geometric form derived from the application of a mathematical formula; its replication gives rise to a surface; the addition of chromatic colour schemes can produce different visual perceptions of this surface, thus enabling the communication of alternative messages. fig. 5. – practical exercises with “sierpinski’s surface” (sierpinskifläche), a.a. 1955-1956, lecturer: tomás maldonado, student: dominique gillard, source: hfg-archiv/museum ulm. fig. 6 offers a worked example of exercise no. 2, again executed by dominique gillard, and entitled “peano's surface" (peanofläche): these images were created by applying the curve theorized by the italian mathematician, logician, and applied linguist, giuseppe peano, in 1890. a peano curve is defined as a continuous line that is generated by joining all the points on an orthogonal grid situated on a given plane. again, this exercise was based on multiple iterations of the basic peano curve sequence. the first image in fig. 6 is a line drawing of a surface defined by a structure. this structure, as stated, was generated by recursively repeating the primary peano curve sequence, in order to trace a continuous line with only one start point and one end point, as an expression of the tension between the finite and the infinite. in this drawing, the dark/light contrast was then used to highlight the basic sequence, then used to create the structure in the second image. the latter was coloured and defined using graduated shades of two chromatic colours: blue and red. the use of the orthogonal grid in both images was of crucial assistance to the student in planning how to lay out and vary the basic sequence across the plane. the differential shading of the two colours produced two geometric figures. the student’s primary focus was on attempting to make these two figures equivalent, such that neither could be defined as the main figure and neither as the background figure. a didactics of colour based on an innovative educational approach at the hochschule für gestaltung in ulm 23 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130202 fig. 6. – exercises performed using “peano’s surface” (peanofläche), academic year 1955-1956, lecturer: tomás maldonado, student: dominique gillard, source: hfg-archiv/museum ulm. it has been shown that ambiguity is best achieved by using colour values with the same intensity of light and luminosity value, or complementary colours with the same degree of luminosity. in this exercise, the peano curve was used with a specific teaching purpose in mind: maldonado chose this curve as a basic figure to work on with a view to fostering rational creativity. creativity, in that this form was already a recognized artistic phenomenon; and rational because the use of the orthogonal grid was an effective means of encouraging a rigorous approach to the design and execution of the exercise. with regard to exercise no. 3, entitled “weierstrass curve” (system weierstrass o weierstrasskurve), for which no worked examples could be sourced, this too involved using a linear geometric construction, namely a weierstrass curve, to create a figure out of empty space. the educational purpose of this exercise was to address the visual perceptual problem of the relationship between foreground and background figures, a theme that was very important to maldonado. the image in fig. 7 exemplifies exercise no. 4. entitled “black as a colour” (schwarz als farbe) and was executed by urs beautler. this practical focused on the use of black in the context of chromatic colours. here, maldonado’s teaching aims were to “train” the students’ visual perception, refining their ability to visually discriminate between colours and to pick out certain tonal values from a set of chromatic interactions. the exercise on black as a colour was based on a combination of contrasting levels of brightness, such that black is not perceived as generating a “hole” effect but functions as a colour. correct solutions showed that black, when featuring among set of solid colours, could be perceived as “brightened” and as a colour in its own right. fig. 7. – exercise in “black as a colour” (schwarz als farbe), academic year 1956-1957, lecturer: tomás maldonado, student: urs beautler, source: hfg-archiv/museum ulm. again, this representation was produced via a recursive pattern of geometric shapes on a square base: starting a didactics of colour based on an innovative educational approach at the hochschule für gestaltung in ulm 24 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130202 from an orthogonal grid formed by minimun sixteen squares, each square was divided in half diagonally. the underlying grid allowed the students to rationally plan out the horizontal, vertical, or rotational patterns they wished to create, by applying the laws of symmetry. fig. 8. – exercise no. 7 “non-exact exact” (ungenaugenau), academic year 1955-1956, lecturer: tomás maldonado, student: william huff, source: hfgarchiv/museum ulm. fig. 9. – tomás maldonado, teaching at the hfg ulm, 1954, with hans g. conrad, almir mavignier, martin krampen and one more student, source: photograph by sigrid von schweinitz maldonado, © hfg-archiv/museum ulm. the image in fig. 8 shows a worked example of exercise no. 7, executed by william huff. entitled "non-exact exact" (ungenau-genau) by maldonado, in this practical, the students were invited to create an image by innovatively applying the technical means at their disposal to work with conventionally accepted formal elements of colour, texture and consistency. with regard to the program of hfg courses in theory of colour specifically, the names of some of the nonpermanent lecturing staff who taught on this module were listed by herbert lindinger in a piece written for the la scuola di ulm exhibition catalogue. hence, we find aemilius muller as lecturer in “theory of colour” between 1954 and 1955; mervyn w. perrine as lecturer in “theory of perception” from 1958 to 1961; and fritz seitz as lecturer in “theory of colour” between 1967 and 1968 (lindinger 1988, p. 40 and pp. 280-282). fig. 10. – these watercolour drawings represent paul klee’s theory of colours as interpreted by three students at the hfg: top: bernd meurer 1956/1957, left: hans von klier 1955/56 and right: klaus franck 1955/56, lecturer: helene nonné-schmid, source: hfg-archiv/museum ulm. the figure 10 documents three practical exercises in colour carried out by hfg students: top: bernd meurer (1956/57), left: hans von klier (1955/56) and right: klaus franck (1955/56). these watercolour drawings were executed as part of the course in colour theory taught by helene nonné-schmidt, an ex-bauhaus student who had taught colour alongside josef albers, albeit with different educational objectives. the task assigned to students was to interpret paul klee’s theory of colours. these three drawings are highly representative of the methodological approach adopted by helene nonnéschmidt during the courses she taught at the hfg from 1953 to 1958. this approach reflected her bauhaus a didactics of colour based on an innovative educational approach at the hochschule für gestaltung in ulm 25 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130202 training, and stands in contrast with the innovative scientific approach adopted by tomás maldonado to initiate his students into the culture and theory of colour. 7. conclusions this article documents the brilliant educational work of tomás maldonado while a teacher at the famous hfg in ulm. the key pedagogical challenge that he pursued was to develop an innovate method of teaching design that was informed by the scientific method and an interdisciplinary and transdisciplinary approach. we have drawn here on the abundance of material held in the hfg ulm archives (hfg-archiv/museum ulm), together with maldonado’s former students’ written accounts of the teaching contents and methods that characterized his courses at the hfg, to present his perspective on teaching design and at the same time to note the pioneering nature of his ideas. with the aim of fostering the teaching and learning of new design competences, he developed a novel educational method that influenced how design was taught in a number of different countries around the world. among the subjects that he taught at the hfg, we have focused on the visual methods module that he delivered as part of the first-year foundation course. even more specifically, we have homed in on the theme of educating to colour as a strategic cultural aspect of designing visual communications and other design products. the practical work produced by the students who attended maldonado’s classes in visual methods offer unique and extraordinary examples of the innovative nature of his teaching experiments with respect to other contemporary approaches. the new principles that he formulated and introduced at the hfg, beginning in 1955, combined scientific method with mathematical calculations and emerging new discipines such as ergonomics, visual communications, signs theory and information theory. in relation to his teaching of colour more specifically, we have observed that it was aligned with his overall educational approach, with a similar emphasis on scientific method, interdisciplinary and transdisciplinary input, and new gestalt studies on visual perception. his theoretical classes on colour drew on analytical studies and applications of logic, as well as constantly appealing to geometry, discrete mathematics, and set theory. among the practical activities described here, some are extraordinary examples of complex aesthetic-formal exercises based on mathematical formulas, the theory of symmetry, early cybernetics concepts, and early versions of fractals such as the sierpinski triangle and the peano/hilbert curve. in sum, thanks to the contribution of tomás maldonado, the ulm school in the 1950s saw the emergence of a new pioneering perspective on design and the role of the designer as well as on how the process of designing and producing products was likely to be in the future. in those years, there was still no mention of environmental sustainability, but maldonado’s approach laid the theoretical ground for the introduction of environmental design by virtue of his principle of “cooperation among disciplines". 8. acknowledgments i am particularly grateful to professor tomás maldonado for his commitment to and rigorous scholarly pursuit of an experimental approach to teaching colour and other themes in the domain of visual perception that he held to be especially important. this paper has been written in his honour and in memory of his exceptional qualities as a tireless purveyor of visual and aesthetic education, as well as the pioneering founder of dedicated design schools. especial my gratitude to the hfg-archiv, the archives of the hochschule für gestaltung of ulm (https://hfg-archiv.museumulm.de/en/), and to museum ulm for their respectful conservation of a corpus of valuable educational material that includes the drawings and objects created by students at the hfg. as well as photographic documentation of educational activities conducted by the teachers who played a leading role in the exceptional history of this important international school. i wish explicitly to thank franco clivio for his critical support. 9. statement on conflict of interest the author declares that no conflict of interest, real or potential, including financial or personal links with other persons or organizations, up to and including the threeyear period following the presentation of this work, that could inappropriately influence the reported research outcomes. 10. statement on sources of funding the author did not receive subsidies from any public, private, or non-profit funding agencies in support of this research. 11. short author biography anna poli holds a degree in architecture from milano politecnico (1991), and a phd in bioengineering (2007). https://hfg-archiv.museumulm.de/en/ a didactics of colour based on an innovative educational approach at the hochschule für gestaltung in ulm 26 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130202 she is currently researcher and professor in cinema and visual art at the “riccardo massa” department of human sciences for education, university of milano-bicocca, italy. her current research interests include: cinema and visual art in educational contexts, cinema and colour vision impairment, the language of imagine and human visual perception, media and digital technologies in school settings, emergent interactive technologies for colour blindness, interaction with computer graphics, creativity and design. during the 2000-2001 academic year, she was visiting professor at stanford university, san francisco (ca). she has authored numerous papers and conducted interdisciplinary experimental research on colour perception, film education, digital media in didactics and educational settings. references aydemir, a. z. (2018). learning from pedagogical experiments. an alternative reading of architectural design studio. eurau18, javier sánchez merina, alicante, pp. 116-122. anceschi, g. (1983). design di base, fondamenta del design. ottagono, 70, 18-23. bonsiepe, g. (2019). convergenze/divergenze. hannes meyer e la hfg ulm, riccini r. (ed.), tomás maldonado bauhaus. feltrinelli, milano. campos, á. l.f. roldán, e. b. and sánchez moya, m. d.(2015). de la intuición a la metodología. propedéutica del proyectar en el curso básico de la hfg ulm. rita_revista indexada de textos académicos, n.4, pp 110-117. chiapponi, m. (2018). ritratto di un intellettuale che ha operato in molti campi, https://ilgiornaledellarchitettura.com/web/2018/12/04/tomasmaldonado-1922-2018/ escot, l. (2007). tomás maldonado: itinerario de un intelectual técnico. patricia rizzo, buenos aires. escot, l. (2002). (ed.), tomás. una biografia ragionata, seniorservicebooks, 25 aprile 2002. frampton, k. (1974). “apropos ulm: curriculum and critical theory”, labour, work and architecture. phaidon, london, pp. 44-63, 2002. (first published in oppositions) no. 3 may 1974, pp. 17-36. garcía, m. a. (2010). tomás maldonado in conversation with/en conversación con maría amalia garcía, fundacion cisneros, new york. herbst, m. (2017). art concret, basic design e meta-design. tugboat , volume 38 (2017), no. 3, pp 324. 328. hörmann, g. and krampen, m. (2002). intervista a tomás maldonado, video-recorded interview, milano. huff, w. s. (1984). william s. huff. la diàspora. autoritratti di venti protagonisti della hfg. il contributo della scuola di ulm/the legacy of the school of ulm. rassegna 19/3, iv, pp 35-39. huff, w. s. (2009). albers, bill e maldonado: il corso fondamentale della scuola di design di ulm (hfg), tomás maldonado, catalogo della mostra, electa, milano, pp. 104-121. leopold, c. (2013). precise experiments: relations between mathematics, philosophy and design at ulm school of design. nexus network journal, 15(2), pp. 363-380. lindinger, h. (1988). la scuola di ulm: una nuova cultura del progetto. costa & nolan, milano. maldonado, t. (1963). ist das bauhaus aktuell? ulm 8/9, september, hfg di ulm, pp. 5-13. maldonado, t. (1984). ulm rivisitato. il contributo della scuola di ulm/the legacy of the school of ulm. rassegna 19. maldonado t. (1992). reale e virtuale. feltrinelli, milano. maldonado, t. (2009). ist das bauhaus aktuell? filmconference festakt zum 90. gründungsjubiläum des bauhauses bauhaus-universität. weimar germany. maldonado, t. (2010). documento 1: corso di base. il verri, 43, pp. 2532. maldonado, t. (2010). arte e artefatti. feltrinelli, milano. neves, i. c. and rocha, j. (2013). the contribution of tomás maldonado to the scientific approach to design at the beginning of computational era the case of the hfg of ulm. wick, r. (1993). pedagogía de la bauhaus. alianza forma editorial, madrid. https://ilgiornaledellarchitettura.com/web/2018/12/04/tomas-maldonado-1922-2018/ https://ilgiornaledellarchitettura.com/web/2018/12/04/tomas-maldonado-1922-2018/ 37 color culture and science journal vol. 12 (2) doi: 10.23738/ccsj.120205 light and colour at the theatre in paolo bini's works for francesco de gregori maria letizia paiato1 1 academy of fine arts of macerata, macerata, italy. ml.paiato@abamc.it corresponding author: maria letizia paiato (ml.paiato@abamc.it) abstract in march 2019, the italian singer-songwriter francesco de gregori sang at the teatro garbatella in rome in front of an audience of 230 spectators, according to a choice that has privileged aspects of intimacy and listening. this stage offered the artist paolo bini an experimental place for the study of an original and unusual set design. in fact, the environment work cromatismo emozionale in ritmo variabile (emotional chromatism in variable rhythm), enhanced the involvement of the spectators and free expression of emotions, using bright and iridescent colours. this contribution is an evidence of how contemporary art exploiting certain technical rules of theatre performance, through the colour that interacts with light has cooperated in theatrical communication by enhancing music and sound. more and more in recent years, the sets of concerts are a meeting place between various forms of art and techniques, between music and visual art and where set designers have more and more space to express themselves by appealing to the use of technology. in this case, bini has not resorted to any technological support, simply leaving to the work/backdrop of a stage the task of creating dynamism to the entire show. finally, aspects related to the artist's research were also highlighted, placing him in continuity with the history of art and the abstract poetics of the twentieth century. keywords francesco de gregori, paolo bini, garbatella, colour, chromatism, painting, abstractism received 10/11/2019; revised 20/11/2019; accepted 05/12/2019 light and colour at the theatre in paolo bini's works for francesco de gregori 38 color culture and science journal vol. 12 (2) doi: 10.23738/ccsj.120205 1. introduction from 27 february to 28 march 2019, the italian singersongwriter francesco de gregori sang at the garbatella theatre in rome in front of an audience of only 230 spectators, according to a choice, desired and sought after by de gregori himself, who privileged intimacy and listening. this choice concentrated the tone of "confidentiality" that characterizes the twenty concerts in the programme in its title off the record. the concerts were not recorded and were therefore transformed into a series of unique and unrepeatable moments: “here lies one whose name was writ in water, said john keats. well, these concerts are written on the water”, said francesco de gregori who, with his band formed by guido guglielminetti on bass and double bass, paolo giovenchi on guitars, alessandro valle on pedal steel guitar, mandolin and guitars, and carlo gaudiello on piano and keyboards, evening after evening played an everchanging lineup. in addition to his most famous mainstream songs (la leva calcistica della classe ’68, titanic, alice, la donna cannone), he proposed a repertoire of rarely performed songs such as festival, i matti, quattro cani, as well as san lorenzo or a pà dedicated to pier paolo pasolini. this stage and this concept were offered to the artist paolo bini as an experimental place for the study of a set design, an original and unusual site-specific environment work. in fact, if normally for a musical concert at the theatre the tendency is to enhance the few instrumentalists on stage and the singer, through colour differences between the mixture of mainly gray and blue light shades, the environment work cromatismo emozionale in ritmo variabile has enhanced the involvement of the public and free expression of emotions in the use of bright and changing colours. distinctive bright and iridescent colours are in the work of the italian artist who, since the beginning, has been interested in a research between matter, light, and colour, where the landscape is the subject and privileged object of his work and is reorganised by virtue of the expressiveabstract dictation, which is typical of the experiences of twentieth century art, according to a current and contemporary vision. this vision never disregards the value of painting as an infinitely living language, let alone a "doing" that unwinds in a typically traditional action if you like. this contribution is proposed as part of the 15th conference of colour, held from 5 to 7 september 2019 at the academy of fine arts in macerata, and is therefore an evidence to how contemporary art, using certain technical rules of show performance, has cooperated in theatre communication enhancing music and sound with great simplicity and naturalness, in this specific case, although for the lighting of a stage space there are not always valid scientific precepts, through the colour that interacts with the light. 2. paolo bini. the landscape, colour, and environment work cromatismo emozionale in ritmo variabile in the interaction between light and colour paolo bini was born in battipaglia, in the province of salerno, in 1984. he studied set design, graduating from the academy of fine arts in naples in this discipline, and in 2007 he joined the set designer gerardo viggiano at the cinespettacolo del grancia in brindisi montagna, as his assistant. from the very first steps in the world of art, the theme of landscape and colour are at the centre of his interests, investigated first of all from the observation of both environmental and urban nature, and both in terms of landscape and view, to extrapolate, and then emphasize, the colour entities that make it unique and extraordinary, but also particularly attractive to man. as is well known, the landscape in western artistic culture became a subject of specific interest from the seventeenth century onwards. think, for example, of extraordinary works on the ideal and classical landscape such as the flight into egypt by annibale carracci, or those by nicolas poussin and claude lorrain, although previous examples of interest for this iconography however never the subject can be found in artists such as leonardo da vinci, to whom we certainly owe, with the study of the nuance, one of the first investigations on the nature and perception of colour. still, think of how nature and colour have always been evaluated by artists as an indissoluble pair, in the proofs of the natural sublime, or in categories such as picturesque, peculiar to the eighteenth century. finally, consider the impressionist nineteenth century totally dedicated to the study of light, up to the first experiences of expressionist and then abstract avant-garde, which we can summarize by citing names such as vasilij vasil'evič kandinskij, paul klee, kazimir malevič, or piet mondrian when he says: “nature (and what i see) inspires me”. about colour, we cannot but remember matisse, one of the first artists to claim that it was the relationship between colours, in a painting, not forms, that gave it a structure: “composition is the art of arranging the various elements available to the painter in a decorative manner to express the painter’s feelings... the main aim of colour should be to serve expression as well as possible” [1]. this expressiveness is not so much deduced from the theories of colour, but instead from observation and feeling, unlike other artists who, in the same period of time, took into account primarily the novelties introduced by science. think of gaetano previati who, in 1906, published princìpi scientifici del divisionismo [2] (scientific principles of light and colour at the theatre in paolo bini's works for francesco de gregori 39 color culture and science journal vol. 12 (2) doi: 10.23738/ccsj.120205 divisionism), a text that certainly influenced the entire futurist movement and in particular the research of umberto boccioni. think of delaunay, of the orphism and his studies on chévreul, but especially look at the already mentioned paul klee, works such as la luce e molto altro ancora (the light and much more) of 1931, where the main interest of investigation of the artist is clear. it is no coincidence that klee found himself with vasilij vasil'evič kandinskij, who was undoubtedly a pioneer in his studies of light, form and colour, and in his research into the constant comparison of music and painting, to teach at the bauhaus where, together, they codified a concept of art that was not only synaesthetic but also symbolic. with a leap through the twentieth century, the abstract approach with the real, with the world, and again with the landscape, is found in the new wind of the informal and in the very origin of expressive action, and then again, in those experiences, so-called analytical painting, that developed from the 1970s where, having abandoned the discourse on nature, everything focuses on the analysis of the material components of painting, first of all the colour, which thus loses the last referentiality with reality and expressiveness. paolo bini faced all this heritage of research and poetry and carried out his own artistic path along the links of expressionism and lyrical abstractionism to finally arrive at the codification of his own personal language which, as we have just said, starts from the initial observation of the landscape, or more precisely from the horizon. this also gives rise to a reflection on the compositional structure of his paintings. bini visualizes this reflection in the synthesis of vertical or horizontal lines, a sort of grid, in essence, which becomes in his poetics the rhythm of real narrative spaces, intervals characterized only by colour aimed, not only to suggest the residual colours of the landscape, but to solicit empathy and emotional experiences in the viewer. this research was carried out as a result thanks to a first experience in south africa in 2013, the place where a new consciousness of nature and colour matures, has now become its distinctive feature, but also the ground for a continuous evolution that, in the most recent works, has been pushed into ever more daring and spectacular chromatic experimentations. although always faithful to his own system of verticals and horizontals, the recent flexion towards thinner lines and the use of fluorescent and brighter colours, is leading the artist to new frontiers of research. on the one hand, the image itself is exasperated and the idea that it is formed according to the unity of the pixel is exaggerated; on the other hand, the increasingly obsessive concentration on colour, on its psychology and on the reactions of people to chromatic frequencies, makes his work something extremely contemporary. the interest of the critics in his work is shown by the numerous and important personal and collective exhibitions and awards that enrich his career. among the most prestigious awards in 2016 is the cairo prize, 17th edition, while his works are kept in italy at the fondazione donna regina museo madre in naples, in the collection of the cairo prize in milan, and in the collection of the luigi di sarro centre in rome. abroad, at the leeu collection of franshhoek in south africa and in the same country, at the public works collection of cape town. finally, the performative work trovo luce was presented in july 2019. this work was created for a public space and as part of an exhibition dedicated to the artist's performance at iscp international studio & curatorial program in new york, confirming the artist's interest in the search for light-colour interaction. fig. 1. paolo bini, astrazione introspettiva con varco centrale, 2017. acrilico su nastro carta su tela, cm. 120x120.ph. © carlo ferrara. fig. 2. paolo bini, eden, 2017. acrilico su nastro carta su tela, cm. 120x120.ph. © carlo ferrara. light and colour at the theatre in paolo bini's works for francesco de gregori 40 color culture and science journal vol. 12 (2) doi: 10.23738/ccsj.120205 the environment work cromatismo emozionale in ritmo variabile, a set backdrop created for the concerts of francesco de gregori's garbatella in rome, held between february and march 2019, is based on these concepts, in perfect continuity and consistency with the artist's own poetics. however, the artist has challenged himself with this work, not only because it is a large work, but also with the concreteness of a real set backdrop consisting of one cotton cloth of the size of 496 x 950 cm, as well as with the specific needs of a theatre and a specific music performance, deliberately arranged by francesco de gregori to create an intimate and confidential atmosphere with the spectators. past experiences, similar but not equal, of environmental works are not unusual to paolo bini. here we recall, for example, the large wall painting created for the exhibition left behind at the royal palace of caserta in 2016, a real example of installation painting and with purely scenic sequels where, however, the artist acted directly on the wall. cromatismo emozionale in ritmo variabile imagined by bini, whose general poetics, as already mentioned, moves essentially around the concepts of emotion and sensation that generate colour, has found, at the garbatella in rome, first of all, a semantic correspondence with the concept of the show itself designed by francesco de gregori, to be configured, later, not as a traditional work, but as a series of elements capable of embracing the spectators. the work/backdrop, made with acrylic painting, was therefore crossed by vertical coloured segments of abstract mould that, in the alternation between white and various mostly fluorescent colours with an iridescent character, however affected by black spots, with a wide chromatic scale including red, orange, pink, green and fluorescent yellow, reacted in an extremely pervasive way in the interaction with the stage lights. fig. 3. paolo bini, cromatismo in ritmo variabile, 2019, teatro garbatella roma. more and more in recent years, the sets of concerts are a meeting place between various forms of art and techniques, between music and visual art and where set designers have more and more space to express light and colour at the theatre in paolo bini's works for francesco de gregori 41 color culture and science journal vol. 12 (2) doi: 10.23738/ccsj.120205 themselves by appealing to the use of technology. in this case, bini has not resorted to any technological support, simply leaving the task of creating dynamism for the entire show to the painting and the scanning of coloured vertical segments hit by light beams. taking into consideration some of the possibilities underlying the role played by the lights, i.e. visibility, revelation of forms, vision and creation of an atmosphere, cromatismo emozionale in ritmo variabile has shown itself properly in its form of a painting, supporting the same proscenium but managing at the same time to subvert the traditional set relationships and frontality with the spectators. in fact, the possible degree of flattening of the scene has been cancelled out by the performance characteristics inherent in the work, thus contributing in the interaction between colour and light, to restore depth to the place of action, generating three-dimensionality also to the stage presence of the musicians and to space. as can be seen from the sketches renderings that describe the three-dimensional scene, in cromatismo emozionale in ritmo variabile, paolo bini has composed a sequence of very precise colours, taking into account the background because horizon, or the infinite where the eye and imagination move. all this, harmonizing and dialoguing with the lighting design by andrea coppini, light designer of francesco de gregori who, at garbatella in rome, used mainly lead lights from above, so as to obtain a strong contrast, albeit with some compression effect, side lights to enhance the shadows of the musicians on stage, so as to rebalance the effect of crushing and encourage a sort of three-dimensional modelling but also encourage an emotional atmosphere, and grazing lights, or beams very tangent to the subjects, in order to enhance their presence. in addition, sometimes to support the silhouette effect and return a fascinating halo in the contours and depth of the scene, a light from behind was used to help detach the subject from the background. finally, to meet specific theatrical needs, warm and cold lights were used, once again to give prominence to the objects and create enveloping atmospheres or to make the contours in this case of the musicians clear and precise, taking into account, in the final analysis, the fixity and the very few moments of mobility by the nature of this show. it is precisely in the interaction between the lights and coloured backdrop that we have obtained an even more spectacular emphasis than that which the lights alone or a black backdrop would normally have given back. through light, in fact, cromatismo emozionale in ritmo variabile is activated. under conditions of natural radiation, in fact, the work has the characteristics of a classic painting of the artist, but it is in the reaction to light of fluorescent colours that it changes features, amplifying every aspect of the atmosphere and environment. cromatismo emozionale in ritmo variabile reacted to the presence of white lights by showing its dominant colours, obviously as a result of reflection and crossing, to that of coloured lights (blue, green, purple, red) absorbing and intensifying the dominant colour of the light itself. consequently, the lights produced by point sources, in meeting the environment work of paolo bini, due to the effect of reverberation, have transformed it into its own source of light. a diffused and soft light source where the chromatic surface responds to opaque hues, mirrored where there is a dominance of fluorescent colours and which, in their combination, have chromatically influenced all the space around, including the floor. the artistic literature on colour, and that on colour and light, as is well known, is vast. it is certainly to it that paolo bini looks, and it is through it that one can see the motives behind his research and consequently those of cromatismo emozionale in ritmo variabile. certainly, the use of colours by the artist makes in any work, so the intense introspective value he assigns to it, becomes an interpretative of a "rhythm" or an "out of rhythm" mirroring that which accompanies the individual throughout his life. his works, in general, are always portions of space that welcome the lights and shadows of the surrounding, but it is in an environmental dimension, such as that of the teatro la garbatella precisely, in the study of colours to the reactions of theatrical lights, then and in this case, in the interpretation of a show, which shows how this research, like contemporary art, can be a convincing grammar at the service of music and emotions. bearing in mind that light is communication, since in a performance it is that element capable of mediating the relationship between space and the spectator's perception, it could be said that, by interacting with cromatismo emozionale in ritmo variabile, it behaves, in this case, more than like a brush. this environment work, which never loses its pictorial character, precisely because of this shows the full potential of how different knowledge and languages, respect and amplify the symbolic matrix that has always accompanied the theatre. cromatismo emozionale in ritmo variabile, therefore, highlights this aspect, suggesting how tradition can be innovative despite a future marked by virtuality. light and colour at the theatre in paolo bini's works for francesco de gregori 42 color culture and science journal vol. 12 (2) doi: 10.23738/ccsj.120205 fig.4. paolo bini, cromatismo in ritmo variabile, 2019, teatro garbatella roma. ph. © daniele barraco 3. conflict of interest declaration the undersigned maria letizia paiato declares that the contribution luce e colore a teatro nell’opera di paolo bini per francesco de gregori of which she is the author is not subject to any actual or potential conflict of interest, including financial, personal or other relationships with other persons or organizations within three years from the beginning of the work presented and that it could influence inappropriately or be perceived to influence their work. nothing has affected my objectivity. therefore, there are no potential conflicts. 4. funding source declaration the undersigned maria letizia paiato declares that no funding or research grants have been received in the course of study, research or collection of the manuscript nor to have received any financial support for the conduct of the research and/or preparation of the article. 5. short biography of the author paiato maria letizia art historian and critic, she teaches art history at the academy of fine arts in macerata. ph.d in history of contemporary art, she is interested in visual experiences and communication both of the early twentieth century and of contemporary artists. he is constantly involved in publishing as director of segnonline and editor-in-chief of the magazine segno of pescara. she is the author of the book l’illustrazione umoristica fra otto e novecento a modena. satira, immagini e ricerche (humorous illustration between the nineteenth and twentieth centuries in modena. satire, images and research). notes [1] the citation is from barr jr a.h., matisse: his art and his public, new york 1951, p. 119. [2] previati g., princìpi scientifici del divisionismo, fratelli bocca editori, turin 1906. light and colour at the theatre in paolo bini's works for francesco de gregori 43 color culture and science journal vol. 12 (2) doi: 10.23738/ccsj.120205 references ball p. (2004) colore. una biografia, milano: bur rizzoli. brusantin m. (1999) storia dei colori, torino: piccola biblioteca einaudi. cherchi p. (1978) paul klee teorico, bari: de donato. goethe j.w. (1810) zur farbenlehre, tubinga; trad.it. (1988) la teoria dei colori, milano. itten, j. (1961) kunst der farbe, ravensburg: otto maier verlag, trad.it. (1965) arte del colore. esperienza soggettiva e conoscenza oggettiva come vie per l'arte, milano: il saggiatore. mancinelli s. (2005), illuminotecnica teatrale. dipingere con la luce, libera accademia della luce. kandinskij v. v. (1912), über das geistige in der kunst, münchen; trad. it. (1993) lo spirituale nell’arte, milano: bompiani. kandinskij v.v.(1982) complete writings on art, 1, boston (ma): g.k. hall & co; trad. it. (1989) tutti gli scritti, vol.2, milano: feltrinelli. klee p. (1920), schöpferische konfession, berlin; trad.it. (2004) saba sardi f. confessione creatrice e altri scritti, abscondita. previati g. (1906), princìpi scientifici del divisionismo, torino, fratelli bocca editori. schopenhauer a. (1816), ueber das sehen und die farben, leipzig, trad. it. (2002) la vista e i colori. e carteggio con goethe, montinari m. (a cura di), abscondita. arensi f. (2018), lo specchio di paolo bini, roma: editalia. battarra e. (2017) ‘il mattino’, i colori di un mondo fantastico invadono la reggia. beatrice l. (2018), la pittura, giorno dopo giorno, catalogo della mostra, galleria alberto peola, torino: il cavallo alato. beatrice l. (2017) (a cura di), baldoni a., mazzarella v., villani a., paolo bini. left behind, catalogo della mostra, appartamenti storici retrostanze del settecento (ex terrae motus), reggia di caserta, caserta: il cavallo alato. beatrice l. (2017), ‘il giornale’, anno xliv n.23, nel bene e nel male artefiera vale sanremo. ma la musica cambia. beatrice l. (2017), ‘flimtv’, italian factory (roberto cuoghi, alek o., paolo bini, gian maria tosatti), pp.16-17. bonuomo m. (2017), ‘arte mondadori’, paolo bini il vincitore del xvii premio cairo ripercorre il suo rapporto con la pittura e la storia dell’arte come immersione totalizzante, editoriale giorgio mondadori. buonomo m. (2016), (a cura di), la forma di una nuova generazione, anno xvii, premio cairo, palazzo reale, milano. bucci, s. (2016), ‘corriere della sera’, colori tra l’italia e il sudafrica. paolo bini e la sua arte saranno famosi, milano. catricalà v. (2018), naufragi rosso e oro nell’opera di paolo bini, in mediterraneo rosso e oro, catalogo della mostra, polo museale regionale d'arte moderna e contemporanea, museo riso – cappella dell'incoronata, palermo. deho v. (2016), (a cura di), paolo bini. astrazione modulare, catalogo della mostra, fornace falcone/spazio delle esposizioni, eboli, salerno. paiato m.l. (2018), ‘segno’, paolo bini, mediterraneo rosso e oro, n.269, pp.48-49. paiato m.l. (2017), ‘segno’, paolo bini. left behind, n.261, pp. 34-35. (2016) paolo bini. spazi immensi, catalogo della mostra spazio intesa san paolo miart – milano: marsilio editore quaroni i. (2016), (a cura di), principio di indeterminazione, catalogo della mostra, abc-arte geneova, genova: abc-arte editions. raddi s. (2017), ‘sofà’, notizie – mondo dell’arte, anno xi n.28, roma: editalia trione v. (2017), (a cura di), atlante dell’arte contemporanea a napoli e in campania 1966-2016, milano: electa, milano. troncone a. (2016), frammentare (e deframmentare) il paesaggio / fragmenting (and defragmenting) the landscape, catalogo della mostra, everard read gallery, cape town. . microsoft word 150105 35 color culture and science journal vol. 15 (1) doi: 10.23738/ccsj.150105 imaging colorimeters to evaluate camera monitor systems image quality cristian bonanomi1and kedar sathaye2 1 konica minolta sensing europe b.v., milan, italy. cristian.bonanomi@seu.konicaminolta.eu 2 konica minolta sensing europe b.v., nieuwegein, netherlands. kedar.sathaye@seu.konicaminolta.eu corresponding author: cristian bonanomi (cristian.bonanomi@seu.konicaminolta.eu) abstract over the last few years, we have experienced a gradual increase in autonomous and driver assistance technology. generally, we refer to these systems as adas (advanced driver-assistance systems). a particular aspect of adas is camera monitor systems (cms), a system composed of a camera, a software that performs image processing operations, and a monitor for the driver. these systems help increase the overall safety aspect of the vehicle and increase the visibility of the drivers’ surroundings; therefore, the original equipment manufacturers (oems) must adhere to country specific regulations, necessary to test the robustness of the system. there are several test procedures for assessing cmss, in this paper we will focus to the optical performance evaluation of the system. this includes lighting system, test patterns and an imaging colorimeter accompanied by a software which performs measurements according to the regulations mentioned in iso16505:2019 (iso, 2019). keywords advanced driver-assistance systems, autonomous driving, camera monitor systems, 2d colorimeters, display evaluation received 09/03/22; revised 19/10/22; accepted 08/02/23 imaging colorimeters to evaluate camera monitor systems image quality 36 color culture and science journal vol. 15 (1) doi: 10.23738/ccsj.150105 1. introduction over the last few years, we have experienced a gradual increase in autonomous and driver assistance technology and according to abi research forecasts almost 8 million cars with autonomous or semi-autonomous level by year 2025 (abi research, 2021). the society for automotive engineers (sae) defines six levels of driving automation when talking about vehicles (sae, 2021): from no automation (level 0) to full driving automation (level 5). beyond these levels, many efforts have been made to provide systems that facilitate enhanced driving situations. generally, we refer to such systems as adas (advanced driver-assistance systems) as electronic systems that assist users in driving and parking functions. a particular case of adas is the camera monitor systems (cms): a system composed of a camera, a software that performs image processing operations, and a monitor to illustrate the possible dangers as well as the blind spots around the car, mainly integrated in rear view mirror or side view mirror. although the technical name used in the standards, is camera monitor systems, the automotive market uses different names, and these systems can be referred to as virtual mirrors, digital mirrors, or electronic mirrors. whatever name is used, these systems help increase the overall safety aspect of the vehicle and increase the visibility of the drivers’ surroundings; therefore, the original equipment manufacturers (oems) must adhere to country specific regulations, necessary to test the robustness of the system. in this paper we will discuss about the iso 16505: 2019 “road vehicles — ergonomic and performance aspects of camera monitor systems — requirements and test procedures” (iso, 2019), with particular attention to the optical performance evaluation of the system. to ensure image quality, several tests need to be performed to evaluate monitor characteristics e.g., directional uniformity, luminance, color rendering and sharpness, etc. the components (camera and display) can be measured separately, to easily discover where degradation has occurred, however sometimes it is necessary to test the complete system, a task that requires a high-resolution imaging colorimeter. in the following, we will focus on the materials and methods necessary to test the robustness of the system, which include: a lighting system to simulate different lighting conditions, i.e., direct sunlight or diffuse sky exposure, several test patterns to be used and imaging colorimeter accompanied by a software which performs measurements according to the standard regulations mentioned in iso16505:2019 (iso, 2019). the state-ofthe-art imaging colorimeter and the dedicated software ensures that cms under test is correctly validated. 2. camera monitor systems a cms is a possible technology to replace exterior mirrors, to display the side or rear view on a monitor inside a vehicle (see figure 1). fig. 1. example of a cms system for a truck. top row: cms camera, bottom row: cms display however, since exterior mirrors are fundamental for the safety, it is important to evaluate if a cms can be a source of reduced safety or provide equal or more information to the driver. generally, a cms improves the aerodynamics of the vehicle decreasing wind resistance coefficient and noise. furthermore, it reduces the blind zone area, improving the safety of driving. in 2015 an extensive work (schmidt et al., 2015) was done to evaluate cms as replacement for exterior mirrors in cars and trucks. the authors tested technical aspects as well as human-machine interaction scenarios. although it has only been seven years since the report, many technical issues have been overcome, though some of the aspects underlined in the document are still of interest and imaging colorimeters to evaluate camera monitor systems image quality 37 color culture and science journal vol. 15 (1) doi: 10.23738/ccsj.150105 concern. we recall some of them in the following, leaving to the reader the task of reading the complete report. both external mirrors and cmss have advantages and disadvantages. some of these are related to technical aspects, such as optical quality; for example, resolution, color and contrast rendering, or time behavior properties that happen in critical situations. additional aspects such as exposure adjustments when entering or exiting from a tunnel, or when a road surrounded by trees creates a succession of shadows and sunny areas are considered. these situations and aspects have been improved in the last years, thanks to technological advancements. other aspects are related to intrinsic properties of the two systems: a mirror follows the reflection law, and movements of the head can add 3d information to the driver, while these movements do not affect the vision on a display. furthermore, weather conditions can affect the two systems in different way: under the rain, the drops on the driver’s side window as well on the mirror itself can reduce the mirror visibility, while this condition seems to affect less the cms, if the camera is in a well-covered position and since the display is inside the vehicle. direct sunlight, snow or night driving are other non-standard conditions that must be considered. finally, there are aspects related to the human-machine interaction: some experiments with human drivers have been carried out, resulting in a different perception of speed and distance when objects are viewed through a cms. however, generally, people can adapt quite quickly to this new situation. all these aspects need consideration when using a cms, therefore a procedure performing a range of tests on these systems has been developed in iso16505:2019 (iso, 2019). the standard includes several tests dealing with operating readiness, time behavior properties (evaluating frame rate, system latency), failure behavior, quality and ergonomic requirements, etc. in the following section we are going to focus only on image quality tests. 3. testing camera monitor systems testing camera monitor systems requires several items:  test charts to evaluate different properties of the cms. these charts can be found in specialized stores (i.e., (imatest, 2021)).  illumination of the charts, to simulate different lighting conditions.  the cms camera installed outside of the car.  the computer that elaborates the data of the camera.  the cms monitor used by the driver.  a digital camera or a 2d colorimeter to evaluate the result of cms monitor.  a light source that illuminates the cms display, to simulate i.e., direct sunlight. an image presenting the setup and the necessary elements for evaluating the image quality of the cms is shown in figure 2 (the bottom row represents a schematic view of the same setup). however, other light sources can be added to this setup to evaluate other conditions, like the contrast rendering under different ambient illumination conditions (please refer to section 3.2). fig. 2. setup to evaluate a cms system: 1) cms camera, 2) lighting system for the target, 3) printed target, 4) cms display, 5) 2d colorimeter for cms evaluation. the evaluation of a cms requires several tools and a dedicated facility. for this reason, such tests are usually conducted directly by oem (original equipment manufacturer) or by specialized independent third-party laboratories. these laboratories provide technical services offering verification, inspection, and certification of several products in accordance with international and national standards as well as audits for systems management certification (i.e., (tuv, 2021)). in the following, we are going to address the previous elements, with particular attention to the evaluation of the optical characteristics of the cms system. these tests can be divided in five sets: 1) to verify the basic imaging colorimeters to evaluate camera monitor systems image quality 38 color culture and science journal vol. 15 (1) doi: 10.23738/ccsj.150105 characteristics of the display like luminance, contrast and uniformity; 2) to evaluate potential issues related to the driving conditions: readability of the display, lens flare due to direct light, etc.; 3) to ensure the colors are correctly reproduced, i.e., for identifying the traffic lights; 4) to take in consideration or alert the driver about possible artefacts, and 5) to assess the resolution and sharpness of the system, in order to identify details. 3.1. monitor isotropy the monitor isotropy test aims at evaluating the optical characteristics of the display according to different positions and viewing directions, using a uniform 70% gray scale image. measurements of the directional uniformity are performed using a goniometer or a conoscope. a conoscope (figure 3, left) is a special lens that can be plugged to a 2d colorimeter to measure the angular distribution of luminance, contrast and color of a display. lateral uniformity is measured on 9 positions on the display which coordinates are specified in the standard. 3.2. luminance and contrast rendering the evaluation of luminance and contrast rendering is done on five different ambient illumination conditions that can affect the monitor readability. these conditions simulate: direct sunlight, diffuse skylight in day condition, night condition and sunset condition. generally, a test chart composed by a white and black chessboard, is illuminated by two light sources, with a defined spectral power distribution, color temperature and illuminance value. the sunset condition is simulated using a direct light source reflected in a mirror towards the cms camera, to evaluate artifact like blooming, smear and flare. 3.3. color rendering this test is used to verify the cms capability to reproduce eight specific colors (red, green, blue, yellow, cyan, magenta, black and white, placed on a 18% neutral gray background), in an accurate way. the test chart used for the color rendering should satisfy a range of conditions, including (see also figure 4c):  the color patches are placed on a circle, in order to keep the same distance from the center.  opposite patches should have complementary colors.  the illumination of the chart should simulate cie d65 and have a cct of 6500 k +-1500k. to verify the accuracy of color rendering, a spectroradiometer or a colorimeter should be used to measure the chromaticity of the chart as well of the cms monitor and convert them to the cie 1976 uniform color space. the measurements done on the monitor are converted in chromatic hue angle to verify that they are in the correct range, while the measured data of the chart are not used for any calculation but to confirm the appropriateness of the used color chart and illumination. 3.4. artefacts the possible artifacts and their drawbacks should be listed in the opertaor’s manual: smear, blooming and lens flare, can cause partial occlusion of the field of view that shall not cover more than a specifc percentage; point light sources, simulating low beam headlamps of another car, should be rendered as distinguishable lights; color noise and chromatic aberration should be avoided or minimized details. 3.5. sharpness and depth of field other important tests of cms regard the sharpness and the related properties: resolution and depth of fields. sharpness is measured evaluating the mtf50(1:1) (modulation transfer function) of a chart composed by five black squares slightly tilted. in order for a cms to recognize object of interested behind the vehicle, also the depth of field needs to be measured. 3.6. regulation no. 46 – addendum 45 european regulation no. 46 (ece r46, 2020) regulates the principles for the approval of motor vehicles for the installation of rear-view and side-view mirrors, in europe. this standard is based on iso 16505: 2019. the addendum 45 specifically, addresses considerations and procedures about the display-based systems as an alternative to conventional mirrors. this addendum adds a couple of tests for evaluate cms:  gray-scale rendering: this test aims at verifying that the cms can display at least 8 tonal gray steps distinguishable from the darkest to the brighter.  point light sources: this test is used to verify that the cms can recognize and render as distinguishable two-point light sources (to simulate passing beam headlights). in particular, a set of two point light sources located at a distance of 250m from the cms camera, having a luminous intensity of 1750 cd and separated each other by 1.3m, should be distinguishable. 4. using a colorimeter for cms evaluation systems all the mentioned tests need a specific instrument able to inspect luminance, color and fine-details. a spot meter device (both a filter-based chroma meter or a spectroradiometer) could be used, due to its capability of measuring the luminance and color in an accurate way. imaging colorimeters to evaluate camera monitor systems image quality 39 color culture and science journal vol. 15 (1) doi: 10.23738/ccsj.150105 however, doing repeated measurements is time consuming, and spatial measurements, like sharpness or blooming test, cannot be performed. fig. 3. example of a 2d colorimeter, used for cms evaluation. on the right, the colorimeter with a conoscopic lens mounted. on the other hand, a digital camera can provide high resolution images, but cannot measure luminance in accurate way or a traceable color rendering. to follow this standard, color accuracy is an extremely important factor, and digital cameras, which are typically used in consumer photography, are designed to please the viewers, enhancing color saturation, rather than reproduce color accurately. furthermore, the color generation in digital cameras is achieved by a bayer pattern, and the process of raw conversion can affect color. spot meter digital camera 2d colorimeter directional uniformity d x y (conoscope) lateral uniformity d d y gray scale rendering d d y color rendering d x y point light source d y y sharpness / d.o.f. x y y table 1. comparison between devices to perform specific tests. x: cannot be done, y: can be done, d: can be done with difficulty. an imaging colorimeter, also known as 2d colorimeter, (figure 3) is the optimal solution to evaluate the image characteristic of the cms, since it comprises the accuracy of a chroma meter and the flexibility of a digital camera. the color measurement is done through four filters that carefully simulate the cie color matching functions. the fourth filter is used to simulate the small peak of the �̅� cmf in the blue side of the spectrum. these filters are placed on a rotating filter wheel, so that four different images are taken, to maximize resolution without spatial interpolation, as happen in typical digital cameras. this is a key point to consider, since for testing cms, the 2d colorimeter needs much higher resolution than the camera and monitor that constitute the cms. another significant point requested by the standard is the necessity to evaluate the directional uniformity of the monitor. some colorimeters allow the use of a special conoscopic lens (figure 3, right), which through fourier optics can map an emitting spot so that each pixel of the sensor corresponds to a different emission angle. radiant vision systems (rvs, 2021), provides hardware that fulfills the standard requirements and a comprehensive software suite to evaluate camera monitor systems. table 1 shows the ease to perform the required tests using different type of devices. in figure 4 three screenshots from the software are presented. figure 4a) shows the interface, which allows the selection of an analysis test (top image), and the parameters that can be set for the specific function (bottom image). in the example, the test “contrast rendering” is selected, with the “direct sunlight” as lighting condition, to reflect one of the standard requirements. figure 4b) shows an image taken with the conoscope. this is a false color representation of the luminance in a specific point of the display, expressed in polar coordinates. for the display under test, the luminance decreases with the angular viewing. when observed perpendicularly (white area), the luminance is around 700 cd/m2. at the cursor point, with coordinates [inclination 50°, azimuth 135°], luminance is around 380 cd/m2 (light blue). for this specific display the image shows that the display is very dim when observed from below, a condition that of course does not occure in a car. figure 4c) is an acquisition of the color rendering chart. the software helps the user to correctly register the patches, and after the execution of the analysis, returns a pass/fail result according to the standard requirements. figure 4d) shows how two point light sources appear in the acquisition that simulates passing headlights. to perform this test, it is usually used a lighting device composed by two high intensity leds placed not too far from the cms camera. figure 4e) represents the typical checkboard pattern to evaluate the contrast of the display, under various daylight conditions. figure 4f) shows the acquisition of the gray scale rendering pattern, to evaluate if the cms is able to display at least eight distinguishable tonal gray levels. imaging colorimeters to evaluate camera monitor systems image quality 40 color culture and science journal vol. 15 (1) doi: 10.23738/ccsj.150105 5. conclusions in this paper we have seen how cmss offer technological innovation yet create a set of new challenges for inspection that must be validated for the use in advanced levels of autonomous driving. since replacing side and rear mirrors is a safety concern, a complete protocol to test these new technology platforms is necessary. different regulations are in force in different countries (i.e in us: (fmvss111, 2019) and in canada (cvmss111, 2017)). in europe un regulation no. 46 (ece r46, 2020) concerns the approval of devices for indirect vision and of motor vehicles with regards to the installation of these devices. this regulation incorporates test standard from iso16505:2019 (iso, 2019), which primary is to offer a guide to evaluate in an objective and critical way the quality and reliability of the cmss. all the tests need instruments able to measure photometric and colorimetric properties as well as some spatial characteristics. in principle, different types of devices can serve the scope: spot meter devices, calibrated digital cameras or 2d colorimeters. however, only the latters can be considered as the optimal solution to evaluate the optical performance of the cms, combining the accuracy of a chroma meter and the flexibility of a digital camera. futhermore, the use of a special conoscopic lens can measure in a single step the luminance at different emission angle. all these aspects have been reviewed in the paper, with a special focus on the optical properties evaluation described in the european standard, and on the necessary tools that an oem or a third part laboratory should use to carry on these tests. fig. 4. screenshots from cms evaluation software: a) analysis selection, b) conoscope measurement for evaluating directional uniformity, c) patch registration for the color rendering test, d) simulation of two-points light source, e) checkboard pattern to evaluate contrast, e) gray-scale rendering pattern. imaging colorimeters to evaluate camera monitor systems image quality 41 color culture and science journal vol. 15 (1) doi: 10.23738/ccsj.150105 6. conflict of interest declaration the authors of this article are employees of konica minolta sensing, part of konica minolta inc., the company that acquired radiant vision system, whose colorimeter was described and tested in this article. 7. statement on sources of funding the authors did not receive funding from any public, private, or non-profit funding agencies in support of this research. 8. acknowledgment the authors would like to thank weiyu shao (felix) and yusaku kawahara for providing some of the material used in this paper, and matt scholtz for the constant support and guidance. 9. short biography of the authors cristian bonanomi – he received his degree and phd in computer science, at università degli studi di milano, where he worked as research fellow for six years, on colorimetry, human perception, digital imaging. he is currently employed in konica minolta sensing, as light and display sales specialist. kedar sathaye he received the phd from telecom bretagne, where he focused on optics and photonics. he is now product manager of light and display in konica minolta sensing. previously he worked as display expert in panasonic automotive, and in valeo as optical innovation engineer. his fields of experience are in optical engineering, spectroscopy, lighting, liquid crystals, and product development. licensing terms articles published in the “cultura e scienza del colore -color culture and science" journal are open access articles, distributed under the terms and conditions of the creative commons attribution license (cc by). you are free to share (copy and redistribute the material in any medium or format) and adapt (remix, transform, and build upon the material for any purpose, even commercially, under the following terms: you must give appropriate credit to authors, provide a link to the license, and indicate if changes were made. you may do so in any reasonable manner, but not in any way that suggests the licensor endorses you or your use, you may not apply legal terms or technological measures that legally restrict othersfrom doing anything the license permits. copyright: the authors keep the rights to further publish their contents where they want and can archive pre-print and post-print (submitted version and accepted version) and the published version of the pdf of their article with no embargo period. references abi research (2021) abi research forecasts 8 million vehicles to ship with sae level 3, 4 and 5 autonomous technology in 2025, available at: https://www.abiresearch.com/press/abi-research-forecasts-8-millionvehicles-ship-sae-level-3-4-and-5-autonomous-technology-2025/ (accessed: 20 december 2021). cmvss111 (2017) canada motor vehicle safety standard – cmvss 111 – mirrors and rear visibility systems. ece r46 (2020) addendum 45, uniform provisions concerning the approval of devices for indirect vision and of motor vehicles with regards to the installation of these devices. fmvss111 (2019) federla motor vehicle safety standard no. 111, rear visibility. imatest (2021) digital image quality testing, “camera monitor systems” (accessed: 7 june 2021). https://www.imatest.com/solutions/cameramonitor-systems/ iso (2019) iso 16505:2019. road vehicles — ergonomic and performance aspects of camera monitor systems — requirements and test procedures (accessed: 7 june 2021). https://www.iso.org/standard/72000.html rvs (2021) https://www.radiantvisionsystems.com/ (accessed: 20 december 2021). sae (2021), sae levels of driving automation™ refined for clarity and international audience available at: https://www.sae.org/blog/sae-j3016update (accessed: 20 december 2021). schmidt, e. a., h. hoffmann, r. krautscheid, m. bierbach, a. frey, j. gail and c. lotz-keens (2015) ‘final report: camera-monitor systems as a replacement for exterior mirrors in cars and trucks’. federal highway research institute, 91p. tuv (2021) camera monitor systems for the automotive industry https://www.tuv.com/japan/en/camera-monitor-systems-for-theautomotive-industry.html (accessed: 7 june 2021). 70 color culture and science journal vol. 13(1) doi: 10.23738/ccsj.130208 the contribution of black color to visual rhetoric of brazilian packaging of hair care products. camila assis p. silva 1 , thamyres oliveira clementino 1 , thalita gonçalves 2 1 unidade acadêmica de design, universidade federal de campina grande, paraíba, brasil. silva.camila.assis@gmail.com, thamyres.oliveira.clementino@gmail.com 2 unidade acadêmica de arte e mídia, universidade federal de campina grande, paraíba, brasil. thalitaogoncalves@gmail.com corresponding author: camila silva (silva.camila.assis@gmail.com) abstract this paper consists of part of the results of a research in the field of packaging and the connotative uses of black color. the aim is to discuss symbolic values that black intends to evoke, beyond the already known concept of luxury and sophistication. the paper is both exploratory and theoretical, because we use rhetoric and semiotic approach to discuss the role of color, image and text in packaging design. researchers divided the work into two phases. the first one consisted of investigating the possible meanings of black color in the packaging by going to point of purchases and analyzing existent packaging, cataloging them and finding common characteristics. the second phase consisted of a deeper analysis of each new approach found in the first phase. researchers used semiotics as a theoretical framework to investigate visual rhetoric from the relationship among color, image and text. the discussion presented here consists of the results related to the self-acceptance new approach regarding the use of black color in hair cosmetic packaging. keywords: packaging design; black color; rhetoric; afro-brazilian; hair care; semiotics. received 24/01/2021; revised 28/03/2021; accepted 07/04/2021 the contribution of black color to visual rhetoric of brazilian packaging of hair care products. 71 color culture and science journal vol. 13(1) doi: 10.23738/ccsj.130208 1. introduction color is one of the fundamental elements in visual communication and its study is part of the basic training of any professional in the design area. in the field of packaging, whether for the purpose of a denotative or connotative message, the repeated use of certain colors in certain product categories ended up generating chromatic identities at points of sale. for this reason, color has long been used in its potential for communication, identification, and persuasion. denotative message refers to analogical information, that is, the use of color by similarity, mentioning the product it contains. the use of color in packaging, in turn, is not limited to the obviousness sometimes important and necessary for the immediate recognition of a product. the symbolic use of color by metaphor rather than analogy is quite common. it is the use of color in the construction of a connotative message. the connotative use of color becomes possible through meanings that we have built over the years, as well as from established cultural conventions. it is notorious that the use of color in its connotative aspect is somewhat more complex, given the subjectivity and influence of the cultural context. however, when we correlate its use with both image and text it becomes easy to infer the symbolic meanings of color. among the different possibilities of using colors in packaging design, the black color aroused our attention our attention because it is not quite common to find a naturally black product, except automotive products made from oils and greases and some foods like beans. despite this, in recent years, we have seen an increase in the use of black in food and cosmetics. which made us infer the probability that this is due to a connotative intention. according to the historian michel pastoureau (2011), for centuries the meanings of this color oscillated in an ambivalent way, among positive and negative perceptions: life and death; profane and religious; mediocre and sovereign; to name a few. in the case of packaging, the author points out the symbolic relationship between color and the concept of luxury and sophistication, and it is common to find them in highvalue perfume, jewelry, and alcoholic beverage packages. it is notorious that the use of color in its connotative aspect is somewhat more complex, given the subjectivity and the influence of the cultural context. however, this connotative aspect is important once the companies seek to differentiate their products at the point of sale. for that reason, in this paper, black will be addressed as connotative information on packaging. moreover, we present the rhetorical contribution that this visual element has presented in brazilian hygiene packaging that promotes the acceptance of curly hair and female empowerment. 2. the mediatized rhetoric of packaging in the mid-twentieth century, with the advent of supermarkets, packaging began to acquire new functions in addition to containment, protection, and transport (camargo & negrão 2008:26). as the figure of the counter salesperson disappears, the packaging starts to be ‘silent salesman’ (pilditch 1961). from then on, we have come to understand packaging ‘as: a system whose function is technical and commercial and aims to pack, protect (from the production process to consumption), inform, identify, promote and sell a product’ (camargo & negrão 2008:29). the authors also state that it is necessary to ‘understand that packaging is a permanent presence in the communication process’ (camargo & negrão 2008:34). therefore, considering its communicational and persuasive functions, and understanding that the packaging constitutes a support for a ‘hybrid visualverbal language’ (see santaella 2001), we argue the importance of studying and analyzing the relationship between verbal and non-verbal elements under the perspective of rhetoric. the researcher samuel mateus says that rhetoric in the 21st century should be called mediatized rhetoric (mateus 2018:158), once it contemplates ‘persuasion realized (and potentiated) through the media’ with both verbal and non-verbal content. in this sense, studying rhetoric nowadays and in communication media, such as packaging, is to consider the study of verbal rhetoric and of visual rhetoric. consequently, it is necessary to recognize the symbolic and communicative aspects of both verbal and non-verbal elements. certainly, considering packaging, not everything is rhetorical, just as not everything is rhetorical when it comes to information. in certain circumstances, what is intended with the message is just to inform. data such as: food sales denomination; list of ingredients; net contents; expiration date; instructions on how to use; those are examples of technical information that has no intention of persuading, so there is no rhetoric. likewise, the use of colors and images can only be related to a denotative message. however, messages that discuss the product's advantages, as well as ‘connotative information’ (scatolim 2006:5) such as colors, images, and textures, can be considered a ‘rhetorical exercise insofar as it seeks to persuade (make believe) spectators to modify a behavior’ (mateus 2018:21). the contribution of black color to visual rhetoric of brazilian packaging of hair care products. 72 color culture and science journal vol. 13(1) doi: 10.23738/ccsj.130208 thus, it is proposed as ‘mediatized rhetoric’ of packaging, the ability that it must communicate from the combination of words of persuasive character and visual elements (including colors) with the final intention of transmitting certain values to the consumer. unlike classical rhetoric, which is based on speech and argumentative techniques of verbal language, on the mediatized rhetoric of packaging, designers and marketers use visual language techniques in line with short advertising texts. hence, one must understand the characteristics of verbal rhetoric commonly used in packaging, as these will guide the selection and application of color in the packaging. 2.1. analysis of rhetoric by a semiotic approach visual rhetoric, as well as verbal rhetoric, is based on the arrangement of basic units of language. as to visual rhetoric, the language is understood from the concept of ‘image’, which is composed by the union of shapes, colors, figures, among other visual elements that compose a visual message. according to joly (2012), images provoke associations capable of identifying objects, attributing to them a certain number of sociocultural qualities elaborated through conventions. in the semiotic approach, it is possible to understand communication through the image considering it as a visual message. after all, semiotics studies the sign process (semiosis) in the construction of messages meanings, taking to account their use context. signs are any event that produces an interpretive effect, such as words, images, colors, sounds, among others. according to peirce's semiotics, signs can be analyzed through their internal properties about what they represent and all their application possibilities or in the interpretive potential that awakens in their user effects on the interpreter (santaella 2002). the sign relations take place through the object that gives rise to a semiosis. we consider the object as immediate when it represents, indicates, resembles, suggests, or evokes a dynamic object, that is, the original object. moreover, a sign can present itself as an icon (by similarity), index (by suggesting) and symbol (by convention) knowledge about semiotics makes it possible to choose and use signs that are strategic for communicative purposes. according to santaella (2002:70), “colors, textures, composition and shapes have great power of suggestion: a color resembles something with the same color; a shape resembles something that has a similar shape, and so on”. these elements and strategies of visual language can be adopted as a rhetorical resource. in the case of packaging, the decision of which look will be used must be centered on the consumer and on the possibilities of reading that he or she will make from each exposed sign. considering the visual language of the packaging, it is important to emphasize that in the image, color is one of the most important elements to compose the rhetoric. ‘color is an important element of product identification and product association’ (camargo & negrão 2008:177), in addition to having a strong symbolic character. unlike the texts on a package, colors can be identified from a greater distance and, therefore, have a first impact on the consumer, along with the visual elements of shape, dimension, and space. in this case, perhaps, colors symbolic character is already in evidence and the consumer may have intentionally selected a packaging because of it, in the search for a product category or a specific benefit. however, it is to the extent that the consumer interacts with verbal information that color will have the potential to act as persuasive information. it is known that ‘there is no meaningless color. the impression caused by each color is determined by its context, that is, by the interweaving of meanings in which we perceive it’ (heller 2013:18), with the meaning of colors being somewhat dynamic. when applied to packaging, it is the context of use of these colors (type of product in which they are applied, and verbal speech linked) responsible for the perception of their meaning. it is argued in this paper that both the color is influenced by verbal discourses, and in the same may be able to potentiate the effect of words on the consumer. 3. case study: the use of text, image and black color in brazilian cosmetics the research presented in this paper was carried out in the brazilian market. firstly, we aimed to investigate the connotative approaches to the black color usage in food and personal hygiene products packaging. for this, we carried out a field research in some of the main points of purchases of campina grande city (paraíba, brasil) to understand to which extent black color is used in packaging. the first stage consisted of cataloguing products packaging that predominantly adopted the black color. to do so, we developed a chart to register the front image of packaging, products’ category, company’s name, and keywords taken from packaging publicity texts. in this phase, we identify three current symbolic approaches: health, self-acceptance, and superior quality. in this paper, we present the analysis and discussions related to the self-acceptance approach, taking to account the use of black color in hair care cosmetic product packaging. then, we move forward to a second stage, which consisted of a deeper analysis of self-acceptance approach identified in the first phase. so as to confirm the the contribution of black color to visual rhetoric of brazilian packaging of hair care products. 73 color culture and science journal vol. 13(1) doi: 10.23738/ccsj.130208 specific use of black, we expand the analysis comparing those black colored packaging with other packaging from the same company. in this second stage of the research, we aimed to understand how the other visual elements could contribute to the consolidation of the symbolic discourse linked to black color. after all, since color is one of the elements that compose an image, understanding the use of color also means understanding its relationship with the meanings of the other visual elements that make up the packaging. to the extent that consonance was identified among the use of such visual elements, we could infer the potential of that color to generate chromatic identities at points of purchase. therefore, we performed an analysis of the textual and visual rhetorical resources presented in the packaging visual design. we elaborated a third chart that allowed us to observe the resources present in the packaging, highlighting them as agents of rhetoric. this time, the intention was to understand whether these resources corroborate the construction of an oriented discourse. that is, a discourse that could favor the consolidation of chromatic identity through convention. 4. results field research and packaging cataloguing allowed the discourse analysis of companies when they use black color. the figure below shows the second chart model with some of the packaging catalogued. by comparing them, we could perceive they are in consonance with the discourse. this analysis allowed us to infer that we can indeed use color as visual rhetorical element, serving as resource for the construction of specific speeches. fig. 1. visual analysis of the use of black in the acceptance promotion category. source: prepared by the authors based on the research carried out. the contribution of black color to visual rhetoric of brazilian packaging of hair care products. 74 color culture and science journal vol. 13(1) doi: 10.23738/ccsj.130208 packaging with a predominance of black color stand out as carriers of speeches aimed at promoting acceptance to the detriment of other companies' packaging, which with disparate speeches, also adopt different colors with different purposes. this sort of predominance in packaging allows black color to be elucidated as a rhetorical resource to reinforce textual and imagery discourses. to further understanding this strategy, we extracted the main packaging verbal information (figure 2) to analyze the possibilities of correlation between image and text. packaging / verbal message packaging 01 powerful curls. bunch at its best. the “otily powerful curls” curls activator has exclusive aminorepair technology, a mass repository composed of biofunctional amino acids and innovative active bioadhesive, obtained from the association of chia and flaxseed polysaccharides, it adheres to the hair fiber, forms a resistant and flexible film, which defines and protects the curls, keeps the hair flexible, disciplined, aligned and with natural appearance for longer. packaging 02 curls yes! developed for powerful women, curls yes! is a line of products for frizzy and curly hair, created exclusively to highlight the best of each curl and enhance the natural beauty of the hair” packaging 03 daily and very luxurious treatment for hair thirsty for life. also excellent for use after staining or other chemical processes. our sudden death treatment is like that, either you love it or you don't know it. it penetrates the hair strands without asking permission, ending the days of dry and blown hair without pity or mercy. sudden death. packaging 04 contains coconut oil + d-panthenol + shea + 6 powerful oils. it leaves hair soft, powerful and lighter. phyna* fragrance, a luxurious consistency, hydrated, healthy and soft threads, curls that shine. *brazilian slang for the portuguese word fina, which can be translated for posh packaging 05 completely relaxed, without parabens, petrolatum, silicones, and sulfate. it still contains in its formula the intense oil of baobab seed, which besides having a miraculous hydrating power, is perfect for you who brings attitude and power in your head. i remove the tangled knot. i cure weakened strand of hair. i remove dryness. i solve everything in 3 minutes. packaging 06 i bring the beloved shine. i remove the split ends. i undo knots. cure frizz, holy powerful black. contains baobab seed oil. without parabens, petrolatums, silicones and sulfate. fig. 2. verbal message contained in the 11-packaging selected for analysis. source: prepared by the authors based on research we could verify the use of black in personal hygiene packaging to promote the empowered female and the use of curly hair. all packaging we analyzed used, to expose this approach, verbal message oriented to the promotion of female empowerment and the use of curls. they used catch phrases or tips, as observed through the words highlighted in the previous figure. it is important to highlight that the black packaging selected present as textual discourse two ways to promote acceptance: one being linked to the use of curls; and the other encourages female empowerment. nevertheless, in addition to the textual, it is also possible to find the use of images that also reinforce the meanings imbued through the texts presented. from the six-packaging presented here, we selected only three of them to a deeper analysis in the present paper [1]. they can be observed in the following image analysis charts, which was based on semiotics. in the analysis of these packaging, we can find somehow the textual discourse reinforced by the images that refer to the concept of ‘promoting acceptance’, such as images of women with curly hair and with attitude or illustrations that evoke it. thus, it was possible to observe symbols and icons associated with female empowerment and the use of curls as imagery recurrence. the contribution of black color to visual rhetoric of brazilian packaging of hair care products. 75 color culture and science journal vol. 13(1) doi: 10.23738/ccsj.130208 fig. 3. semiotic analysis of packaging 02 [2]. fig. 4. semiotic analysis of packaging 03 [3]. fig. 5. semiotic analysis of packaging 06 [4]. the contribution of black color to visual rhetoric of brazilian packaging of hair care products. 76 color culture and science journal vol. 13(1) doi: 10.23738/ccsj.130208 among these visual references to reinforce the discourse, we cite the case of the poster known as rosie, which is a symbol of the feminist movement and was created in the 1940s by the american government with corporate intentions. the image showing a strong and apparently independent woman became famous in the 1970s as a symbol of female empowerment (heine & sales 2020). the use of the female image on the packaging refers to this feminist symbol, the handkerchief in the hair and the woman's position refer to rosie, thus being an icon, since, according to santaella (2002) they refer to their objects through the similarity. the vibrant and contrasting colors, present in most of the packaging analyzed, can be associated with color harmony found both in contemporary afro-brazilian and african fashion. african multicolor way of dressing has influenced brazilian culture (vidal 2018). in the process of adapting to the new culture imposed by slavery blacks ‘brought dance, rhythm, colors, brilliance and adornments, which are present in african brazilian fashion’ (harger & berton 2013). according to the authors, society has neglected the potential market for the black public for a long time. by using colors, which can be symbolically associated with afro-brazilian and african culture in those packaging, companies, reinforce the market niche aimed. the symbol is a sort of sign in which the association is given by a convention process. therefore, the symbolism of those colors could be aroused using other visual references from afro-brazilians such as curly hair. the growing wave of afro-brazilian people empowerment coupled with women's empowerment motivated companies to seek new formulas for their cosmetics as well as changing their marketing plans. this fact can be noticed when ‘internet searches using the terms curly and curly hair, according to data released by google bradlab, increased 232% and 309%, respectively, in the last two years’ (silva, 2017). in this same universe of images, we identified iconic figures of curls in the researched packaging, referring to the wavy hair. 5. final considerations the research revealed the adoption of black color in packaging from categories that were unlikely, such as personal care products. this demonstrates the way of perceiving color as a visual resource, extrapolating analog adoption and expanding it to new meanings that benefit communication. the first stage allowed the verification of the connotative use of black color in packaging of the investigated categories, through shared speeches, which together demonstrate the ability to construct meanings about issues emerging in the current context, such as promoting acceptance. the connotative use can be clearly seen as a strategy for the differentiation among black packaging and its competitors at the point of purchase. the research carried out demonstrated the black color being used as an indication of differentiation at the market shelf. due to the visual contrast, those packaging with black color stand out more than the other ones. at the first glance, color takes our attention. at a second moment, other visual and textual information exert their communicative functions. the use of color associated with a textual discourse and specific and recurring images, among the universe of packaging investigated, corroborate the connotative use that the black color promotes in hygiene products. the meanings we attribute to the black color in this research are confirmed by the content of the textual speeches and the types of images used. the recurrence in the use of black color linked to the concept of promoting the acceptance of curls and encouraging female empowerment leads us to infer the emergence of a chromatic identity for the category of hygiene and personal care products. this is because, in the field of packaging, the repeated use of certain colors in certain product categories ends up generating chromatic identities at points of sale, which assist in communication through assigned meanings. it was apparently made possible the connotative use of black in hygiene products because a convention established by the companies responsible for the packaging design. faced with a demand for differentiation, linked to the emergent discourses in the social context, black tends to be configured as a convenient option. however, we argue that its symbolic value will depend on the quality of textual and visual messages. as color, image and text are integrated in your rhetorical exercise; the chances of a package persuading your audience will be increased. the repetitive use of black in packaging in the hygiene and personal care sector, linked to the same type of textual and visual discourse, contributes to the perception of a common meaning: promotion of acceptance and empowerment. being black the color of strength and social struggle. with that, the perception and representation of the black color becomes one. it is likely that other products with a similar configuration and represented by the black color will be perceived as such. the packaging with a predominance of black color, found during the research, demonstrated a new perspective for the adoption of color in the current context. it consists in the contribution of black color to visual rhetoric of brazilian packaging of hair care products. 77 color culture and science journal vol. 13(1) doi: 10.23738/ccsj.130208 the use interconnected to the construction of a connotative approach, through issues that have been recently erected in the social space. important topics such as acceptance have been the subject of discussion, and therefore have been consolidated in the public's imagination. this issue apparently aroused the need for differentiation in companies, with black being an apparently satisfactory alternative. if, on the one hand, the use of black color brings up the discussion of new possibilities of rhetorical approach in the segment of hygiene and personal care, other colors that have been used for a long time in this category of products certainly present discourses that are worth studying. to continue this study, we would recommend carrying out a packaging investigation based on the sales verbal discurse, instead of starting it based on the black color of the packaging. afterall, do other colours could also promote curly hair empowerment and acceptance in the context of hygiene and personal care? 6. conflict of interest declaration the authors declare that there is no conflict of interest regarding the publication of this paper. 7. funding source declaration this work has been supported by funds from the federal university of campina grande (universidade federal de campina grande). 7. acknowledgement we wish to thank the federal university of campina grande (universidade federal de campina grande) for allowed us time for dedication to this research during the year of 2019. 8. short biography of the author(s) camila assis peres silva design professor at universidade federal de campina grande. doctor of science (usp), master in design (uerj) and bachelor in industrial design (ufrj). specialist in marketing and e learning (uff). conducts research and teaches in the areas of packaging design, color, visual perception, user centered design, usability, history, and design theories. thamyres oliveira clementino doctor of science (ufpe), master in design (ufcg) and bachelor in design (ufcg). conducts research in the areas of visual perception, design for sustainability and packaging design. thalita oliveira gonçalves graduated in languages and qualified in portuguese by the state university of paraíba (supb, 'uepb' in portuguese). undergraduate student in educommunication ('educomunicação' in portuguese) at the federal university of campina grande (fucg, 'ufcg' in portuguese). notes [1] the six charts are available at https://drive.google.com/drive/folders/ 1cfporqxgy8eb9oyynvqrtvq40dcydsr0?usp=sharing [2] figure elaborated by the authors based on the images available at: http://www.haskellcosmeticos.com.br/produto.php?id=6; https://www.naturallycurly.com/curly-hair/curls; https://theculturetrip.com/africa/south-africa/10-designers-whorebringing-south-africas-style-to-the-world/ (accessed 15 june 2019). [3] figure elaborated by the authors based on the images available at: https:/lolacosmetics.com.br/cabelo/; https://americanhistory.si.edu/collections/search/object/nmah_538122; https://unsplash.com/photos/c676qsbvutg (accessed 15 june 2019). [4] figure elaborated by the authors based on the images available at: https://www.embelleze.com/creme-de-tratamento-novex-meus-cachossanto-black-poderoso/p?idsku=158&gclid=cjwkcaiar6abhafeiwado4sfqpjhi9y0caj6vqxlcn55sjkgwgrjjdfi5xti_tjmev4r9 or3ymz_rocrgiqavd_bwe;https://www.naturallycurly/curly-hair/curls; https://www.facebook.com/julia.vidal.etinias/photos/a.55755346763876 4/1951435691583861/?type=3&theater (accessed 15 june 2019). references andrade, g., ribeiro, c., magalhães, m. and sales, a. (2016) ‘empoderamento feminino através da valorização do cabelo crespo/ cacheado’, revista formadores: vivências e estudos, [online] 10 (6), pp.90-95. camargo, e. and negrão, c. 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(1961) the silent salesman. london: harper & row. the contribution of black color to visual rhetoric of brazilian packaging of hair care products. 78 color culture and science journal vol. 13(1) doi: 10.23738/ccsj.130208 santaella. l. (2002) semiótica aplicada. são paulo: thompsom. santaella, l. (2001) matrizes da linguagem e pensamento. são paulo: iluminuras. scatolim, r. l. (2006). a importância do rótulo na comunicação visual da embalagem: uma análise sinestésica do produto. available at: http://www.bocc.ubi.pt/pag/scatolim-roberta-importancia-rotulocomunicacao.pdf. (accessed 17 may 2019). silva, c. (2017). ‘silenciamento e contradição no discurso das empresas de cosméticos para cabelos cacheados e crespos’, vii – o político na análise do discurso: contradição, silenciamento, resistência. recife, pp. 1-5. vidal, j. (2018) cultne na tv. [television programme]. available at: https://tinyurl.com/yc27t58h (accessed 20 march 2020). microsoft word 150102 13 color culture and science journal vol. 15 (1) doi: 10.23738/ccsj.150102 virtual interior environment: influence of colour on the sense of immersion firdevs gökmenoğlu1 and saadet akbay1* 1 department of interior architecture, faculty of architecture, çankaya university, ankara, turkey. iyibilginfirdevs@gmail.com, akbay@cankaya.edu.tr corresponding author: saadet akbay (akbay@cankaya.edu.tr) abstract this article investigates the effects of colour on the sense of immersion in virtual interior environments. the perceptual significance of colour in interior design necessitates a critical evaluation of the three dimensions of colour hue, saturation, and lightness (hsl) in the context of their application in virtual environments (ves). the study aims to investigate how the sense of immersion in virtual interior environments varies depending on hue, saturation, and lightness and to examine the extent to which colour dimensions influence the sense of immersion in ves. in this study, the hsl colour space was employed to create varying degrees of colours, and an online survey was conducted to understand the individuals’ sense of immersion in different virtual interior settings. the findings suggest that reducing the degree of lightness of colours in a virtual interior environment enhances the sense of immersion. in addition, the study reveals that whether a virtual interior environment highlights natural or artificial lighting, augmenting the degree of lightness of colours intensifies the sense of immersion in the perceived environment. keywords colour perception, colour experience, virtual interior environment, sense of immersion received 11/09/21; revised 04/03/22; accepted 20/02/23 . virtual interior environment: influence of colour on the sense of immersion 14 color culture and science journal vol. 15 (1) doi: 10.23738/ccsj.150102 1. introduction virtual reality (vr) technology provides users with an immersive experience in virtual environments (ves) through the stimulation of various senses in virtual spaces. vr has transformed into a potent technology that facilitates the assimilation of fictionality by stimulating human senses, enabling individuals to inhabit an artificial environment, and converting mental stimuli into tangible sensations (lavalle 2018; kim et al. 2004). alternatively, vr technology has also been identified as a tool that generates long-lasting emotions and memories that endure even after it has been turned off (rizzi el al. 2012). the development of vr technology has advanced rapidly, particularly in the domain of computer graphics, and a diverse range of new vr equipment has been utilized to measure the degree of immersion in ves (feisst 2011; cadet and chainay 2020). immersion is a concept that has been extensively studies in the domain of in video games to create a captivating ve that captures the player's attention. design criteria to improve the vr in 3d video games are considered in terms of the degree of immersion, engagement, and presence (mcmahan 2003). our brains possess the ability to easily adapt to stories and disregard the surrounding world. immersion, or the sensation of being transported, is metaphorically derived from submerging oneself in water. the feeling of being surrounded by water while swimming in the ocean or pool is also described as immersion. compared to air, the sensation of being in the water is an entirely different reality. for instance, learning to swim is a psychologically immersive experience. an experiment that involves immersing oneself in a virtual environment is typically characterised by three elements: flow, cognitive absorption (ca), and presence (jennett, et al. 2008). flow is defined as a situation in which individuals are deeply engaged in an activity in such a way that nothing else matters. flow represents an elevated level of engagement, while immersion eliminates the momentary lapse. thus, immersion can be considered as a prerequisite for flow (skarbez et al. 2017; siple and springer 1983). csikszentmihalyi has identified eight factors that are critical for flow: a balance between challenge and skills, clear goals, clear feedback, a sense of uncertain time, a loss of self-consciousness, a sense of pleasure, and control in an autotelic activity (roohi and forouzandeh 2019). nowadays, vr technology has become popular not only in the field of video games but also in various other areas. immersion allows users to experience diverse ves, enhancing their spatial perception and sense of presence using one-to-one modelling and 3d visualisation technologies (murray 1997). numerous studies have explored the concept of immersion in various media, highlighting the importance of colour and light in virtual environments (wästberg and billger, 2006). martini et al. (2004) state that the human visual system (hvs) exhibits variations in colour perception according to luminance, chromaticity, or whiteness image filters, aiming to identify the most effective hsl values within the hsv system in virtual environments. colour perception is a fundamental distinction between human adaptation capability and colour reproduction. billger et al. (2004) claim that when individuals view a production in a vr environment as an observer, they approach it "out of context" and behave differently than in a real-life situation "in context." stimulating human colour perception is required to integrate to this experience in line with reality perception. zeki and martini's (1998) study on colour processing has showed that designing images as natural, unnatural and achromatic colour stimulate different regions of the human brain. as a result, three-stage cortical colour processing occurs in the human brain. the first stage comprises wavelength difference, consisting of the presence of wavelength and its intensity. the second stage is an atomic constant perception of colour, without any association with memory, judgment, or learning. the third stage is the colour of the object. all these factors influence colour perception in the human brain in both real-world and vr settings (zeki and martini 1998). in addition, brown and macleod (1997) found that different nuances of colours elicit different senses, leading to variations in the sense of immersion in ves. although colour perception is considered one of the factors that influence the sense of immersion in a ve, few studies have focused on colour as the primary subject matter of investigating immersion in spatial contexts (stahre et al., 2009). this article seeks to investigate the influence of colour on the sense of immersion in virtual interior environments. the study aims to explore how the hue, saturation, and lightness of colours affect the sense of immersion and the extent to which colour dimensions influence the sense of immersion in such ves. by doing so, this research can offer insight into how colour perception in virtual interior environments can influence the sense of immersion in a technical and practical manner in the field of interior architecture utilising emerging technologies. 2. the study 2.1. participants the study involved a total of 228 participants, consisting of 165 females and 63 males, with 14 individuals under the age of 18, 62 between the ages of 18 and 24, 84 between the ages of 25 and 34, 38 between the ages of 35 and 44, 28 between the ages of 45 and 64, and two virtual interior environment: influence of colour on the sense of immersion 15 color culture and science journal vol. 15 (1) doi: 10.23738/ccsj.150102 over the age of 65. although 25% of participants reported backgrounds in architecture and interior architecture, the remaining participants represented diverse occupational groups to facilitate a more comprehensive analysis. all participants were of turkish nationality. 2.2 visual stimuli in this study, four different interior images were selected from the website of interior architect kelly wearstler (https://www.kellywearstler.com/) to evaluate the effects of colour on the sense of immersion virtual interior environments. the hsl colour space of adobe photoshop cs6 was utilised to adjust the degree of hue, saturation, and lightness of the selected images, with each image having four different modifications. to make the images appear warmer, the degree of hue in each image was decreased by 10%, while the degree of saturation was reduced by 35% to make the images appear duller. the degree of lightness was adjusted by a range of -35% to +35%, resulting in darker and lighter images (figure 1). the first image was selected for its warm colour tones dominated by intense brown colours, which featured dotted dark elements with horizontal and vertical lines. the second image contained brown and warm tones and was chosen to examine the contrast of the white chair with the rest of the environment. the third image was chosen due to its visually intense reflection of natural lighting, which allowed for the exploration of the effect of sun on the interior environment. the fourth and final image was dominated by cold tones and combined with the reflectivity of artificial lighting to make a comparison with interiors in warm tones. all modifications were done in a controlled manner to ensure consistency and avoid any potential confounding variables. 2.2 hsl colour model the hsl colour model, an acronym for hue, saturation, and lightness, is widely used tool in computer graphics applications. although the hsl model is based on an rgb colour space, its aim is to describe more perceptual colour relationships. thus, in this study, the hsl colour model was deemed appropriate for modifying image. 2.3 measures and procedure in this study, an online survey was utilized to investigate the sense of immersion in virtual interior environments. the questionnaire comprised three sections: demographic features, colour vision assessment, and selection of the most immersive interior image. the first section requested demographic information such as age, gender, and nationality. the second section assessed participants' colour vision using ishahara's colour deficiency test, with participants who passed the test being deemed to have normal colour vision. the third section aimed to determine the extent to which the participants felt immersed in the virtual interior environments presented to them, with participants being asked to select one of four sets of images with varying degrees of hue, saturation and lightness that best conveyed the sense of immersion from a total of four different interior images. given the covid-19 pandemic and the resulting limitations on in-person research, the study necessitated the use of monitors and screens instead of vr glasses to display the interior images. to maximize the study's potential accuracy, certain prerequisites were established. for example, participants were instructed to set their monitor colour settings to rgb, turn off night shift or true tone settings if using a phone, and adjust screen brightness to between 80% and 90%. additionally, participants were advised not to take the survey in bright daylight or in the dark. these measures were implemented to minimise potential variability in participants' responses due to differences in screen settings or lighting conditions. 3. results and discussion after data collection through an online survey, statistical analysis was conducted using ibm spss statistics 23. the data were analysed for frequency distribution, and the results are discussed in relation to each of the four images presented in figure 1. in the first set of images (see figure 1a), a notable 31.1% of participants identified the image with a -35% degree of lightness (referring to #1) as providing the most immersive virtual interior environment in comparison to the other images. in contrast, 24.1% of participants found the image with a -10% decrease in hue (referring to #3) to be immersive, while 23.2% of participants found the image with a -35% decrease in saturation (referring to #4) to be immersive. the results demonstrate that 18.9% of participants found the image with a +35% increase in lightness (referring to #2) to be immersive. in the second set of images (see figure 1b), the image with a -35% degree of lightness (referring to #1) was identified as providing the most immersive virtual interior environment by 32.9% of participants, in comparison to the other images. however, 26.3% of participants found the virtual environment with a +35% increase in lightness (referring to #2) to be immersive, followed by the image with a -35% decrease in saturation (referring to #4), which was identified as immersive by 23.2% of participants. according to the results, only 14.5% of participants found the image with a -10% decrease in hue (referring to #3) to be immersive. virtual interior environment: influence of colour on the sense of immersion 16 color culture and science journal vol. 15 (1) doi: 10.23738/ccsj.150102 fig. 1. interior images used in the study; in each image: 1) lightness: -35%, 2) lightness: +35%, 3) hue: -10%, 4) saturation: -35% in the third set of images (see figure 1c), 33.3% of participants perceived the image with a +35% increase in lightness (referring to #2) as providing the most immersive virtual interior environment, followed by the image with a -35% decrease in saturation (referring to #4), which was identified as the second most immersive by 27.2% of participants. meanwhile, 22.4% of participants regarded the image with a -35% decrease in lightness (referring to #1) as immersive, and 14.9% of them perceived the image with a -10% decrease in hue (referring to #3) as immersive. in the final set of images (see figure 1d), the majority of participants (55.7%) perceived the image with a +35% increase in lightness (referring to #2) as the most immersive virtual interior environment when compared to the other images. the next most immersive virtual environment was the with a -10% decrease in hue (referring to #3), which was considered immersive by 21.9% of participants. the image with a -35% decrease in lightness (referring to #1) and a -35% decrease in saturation (referring to #4) were perceived as immersive by 14.5% and 4.8% of participants, respectively. figure 2 displays the frequency distributions of the sets of images. the findings of the present study align with previous research that suggests that perception of colour plays a significant role in the sense of immersion in ves. more specifically, the study revealed that decreasing the degree of lightness of colours in virtual interior environments enhances the sense of immersion in that environment. in addition, the findings indicate that increasing the degree of lightness of colours, whether in the context of natural or artificial lighting, heightens the sense of immersion in the ve. previous research conducted by siess and wölfel (2019) has examined the effect of colour temperature on the sense of immersion, demonstrating that different nuances of colour can elicit diverse perceptions, leading to variations in the sense of immersion in ves. similarly, kumoğlu's (2013) study on how colour temperature affects wayfinding behaviours in virtual airport simulations indicated that the participants' wayfinding performance virtual interior environment: influence of colour on the sense of immersion 17 color culture and science journal vol. 15 (1) doi: 10.23738/ccsj.150102 varied depending on the colour temperature, as measured by factors such as time spent, deviations, indecision, and direction choice. fig. 2. frequency distribution of the sets of images the perception of space and mental construction of space in the virtual environment are linked to the colour temperature, which suggests that colour values can also influence the sense of immersion in virtual interior environments. stachoň et al. (2018) found that participants' locations, directions, and sense of reality vary depending on the hue, and that the hue has an impact on the virtual environment. taherzadeh (2018) investigated the effect of hue on task performance, and the study's findings suggest that changing the hue caused participants to behave differently. the various hues that cause differences in behaviour in the spatial setup differ in the sense of immersion of the participants in virtual environments. the present study examined the impact of hue, saturation, and lightness on the sense of immersion in virtual interior environments. consistent with prior research, the results suggest that colour perception plays a crucial role in shaping the sense of immersion in ves. it is worth noting that the use of 2d virtual interior environment images in this study, along with the use of online surveys due to the pandemic restrictions, are potential limitations. consequently, the findings can be considered as a preliminary investigation that provides a basis for further research on the impact of colour on the sense of immersion in 3d virtual interior environments. 4. funding source declaration the authors received no specific funding for this research. 5. conflict of interest declaration the authors declare that there is no conflict of interest. 6. acknowledgments the authors thank the participants who voluntarily took part in this study. 7. short biography of the author(s) firdevs gökmenoğlu • master’s student and scholar in the interior architecture department, çankaya university, ankara, turkey. she received a bs degree from the department of interior architecture and a bs degree from the department of architecture at çankaya university. she studied at bauhaus university as an exchange student. her interests include interior design, furniture design, colour design, computer and vr aided design. saadet akbay • assistant professor in the interior architecture department, çankaya university, ankara, turkey. she received ba and mfa degrees from the department of interior architecture and environ mental design at bilkent university, and a phd degree from industrial design at the middle east technical university, ankara, turkey and postdoctoral degree from architecture at the university of lisbon, portugal. her research interests include colour perception, colour education, colour and light, and design education. licensing terms articles published in the “cultura e scienza del colore -color culture and science" journal are open access articles, distributed under the terms and conditions of the creative commons attribution license (cc by). you are free to share (copy and redistribute the material in any medium or format) and adapt (remix, transform, and build upon the material for any purpose, even commercially, under the following terms: you must give appropriate credit to authors, provide a link to the license, and indicate if changes were made. you may do so in any reasonable manner, but not in any way that suggests the licensor endorses you or your use, you may not apply legal terms or technological measures that legally restrict othersfrom doing anything the license permits. copyright: the authors keep the rights to further publish their contents where they want and can archive pre-print and post-print (submitted version and accepted version) and the published version of the pdf of their article with no embargo period. references billger, m., heldal, i., stahre, b., renstrom, k. (2004) ‘perception of color and space in virtual reality: a comparison between a real room and virtual reality models’, human vision and electronic imaging ix, vol: 5292, https://doi.org/10.1117/12.526986 brown, r. o., macleod, d. i. a. (1997) ‘color appearance depends on the variance of surround colors’, current biology, 7(11), 844-849, https://doi.org/10.1016/s0960-9822(06)00372-1 cadet, l. b., chainay, h. (2020) ‘memory of virtual experiences: role of immersion, emotion and sense of presence’, international journal of human-computer studies, 144. 102506, https://doi.org/10.1016/j.ijhcs.2020.102506 camgöz, n. (2000) effects of hue, saturation, and brightness on attention and preference [phd thesis], i̇hsan doğramacı bilkent university. csikszentmihalyi, m. (1990) flow: the psychology of optimal experience, 1st edn, harper & row. feisst, m. e. (2011) ‘enabling virtual reality on mobile devices: enhancing students’ learning experience’, in: spie eco-photonics 2011: virtual interior environment: influence of colour on the sense of immersion 18 color culture and science journal vol. 15 (1) doi: 10.23738/ccsj.150102 sustainable design, manufacturing, and engineering workforce education for a green future, international society for optics and photonics, vol: 8065, 80650p, https://doi.org/10.1117/12.888462. jennett, c., cox, a. l., cairns, p., dhoparee, s., epps, a., tijs, t., walton, a. (2008) ‘measuring and defining the experience of immersion in games’, international journal of human-computer studies, 66, 641661, https://doi.org/10.1016/j.ijhcs.2008.04.004. kumoğlu, ö. (2013) the effects of correlated color temperature on wayfinding: a study in a virtual airport environment [phd thesis], i̇hsan doğramacı bilkent university. lavalle, s. m. (2017) virtual reality, 1st edn, illionis: cambridge press. martini, d., folgieri, r., gadia, d., rizzi, a. (2012) ‘virtual reality as a communication proces’, virtaul reality, 16, 233-241, https://doi.org/10.1007/s10055-011-0200-3 martini, d., rizzi, a., rossi, m. (2004) ‘postfiltering for color appearance in synthetic image visualization’, journal of electronic imaging 13 (1), 111-119, doi: 10.1117/1.1635367 mcmahan, a. (2003) the video game, theory reader: immersion, engagement and presence, a method for analysing 3-d video games, new york. murray, j. (1997) hamlet on the holodeck: the future of narrative in cyberspace, updated edn, the mit press. roohi, s., forouzandeh, a. (2019) ‘regarding color psychology principles in adventure games to enhance the sense of immersion’, entertainment computing, 30, 100298, https://doi.org/10.1016/j.entcom.2019.100298. siess. a., wölfel. m. 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(2006) ‘physical measurements vs visual perception: comparing colour appearance in reality to virtual reality’, conference on colour in graphics, imaging, and vision, society for imaging science and technology, 146-151. microsoft word 150104 27 color culture and science journal vol. 15 (1) doi: 10.23738/ccsj.150104 colour, texture, and luminance: textile design methods for printing with electroluminescent inks delia dumitrescu 1, marjan kooroshnia 1, erin lewis 1 and kathryn walters 1 1the swedish school of textiles, university of borås, sweden; delia.dumitrescu@hb.se, marjan.kooroshnia@hb.se, erin.lewis@hb.se, kathryn.walters@hb.se corresponding author: marjan kooroshnia (marjan.kooroshnia@hb.se) abstract printable smart materials offer textile designers a range of changeable colours, with the potential to redefine the expressive properties of static textiles. however, this comes with the challenge of understanding how the printing process may need to be adapted for these novel materials. this research explores and exemplifies the properties and potential of electroluminescent inks as printable smart colours for textiles, in order to facilitate an understanding of designing complex surface patterns with electroluminescent inks. three conventional textile print methods – colour mixing, halftone rasterization, and overlapping – have been investigated through experimental design research to expand the design potential of electroluminescent inks. the result presents a set of methods to create various color mixtures and design complex patterns. it offers recipes for print formulation and documents the outcomes, offering a new design resource for textile surface pattern designers to promote creativity in design, and provides fundamental knowledge for the creation of patterns on textiles using electroluminescent inks. keywords electroluminescent printing, smart textiles, textile design, texture, colour mixing received 30/03/22; revised 18/11/22; accepted 05/11/22 colour, texture, and luminance: textile design methods for printing with electroluminescent inks 28 color culture and science journal vol. 15 (1) doi: 10.23738/ccsj.150104 1. introduction smart materials have been defined as materials capable of changing from one state to many in response to external stimuli (addington and schodek, 2005). as raw materials for design, smart materials entered the textile practice decades ago (braddock and o’mahony, 1998; mcquaid and beesley, 2005). their presence has enriched the material palette traditionally used by textile designers, and the expressive language specific to the field (kooroshnia, 2017; mossé, 2014). light has proven to be a highly valued design material in the form of leds, optical fibers, and electroluminescent wires, and has been used to complement the expressive vocabulary of textile design, such as in artistic applications (bobeck tadaa, n.d; layne, 2006; loop. ph, 2012; kettley, 2015) and research practices (jansen, 2015; taylor and robertson, 2014; persson and worbin, 2010). in these examples, which combine light and textile construction methods, light sources have been embedded in the design of textile structures or added by embroidery to the textile surface, defining a new category of textiles. accordingly, the intangible materiality of surface design expressed by light combines with the physicality of textiles and produces a hybrid category of expressions resulting from the mixture of these distinct material characteristics: transformative/static, sharp/soft, digital/physical, visual/tactile. these projects exemplify and expand the potential for textile designers to embed directly light into textile structures. yet working with light using textile printing methods, which create a flexible light-emitting surface, is still an undeveloped field. 1.1. electroluminescence electroluminescence (el) was discovered in 1907 and named in 1936. thin film el (tfel or actfel) panels, which provided printable light materials for surface applications, were developed in the late 1950s and became commercially available in 1974. in the 1990s, thick dielectric el (tdel) was introduced and was shown to be brighter and more reliable, and could be produced using screen-printing (kretzer, 2015; deferme and verboven, 2018). el inks work by sandwiching an illuminating layer between conductive and insulating layers: a transparent conductive substrate on which the el ink is printed, followed by the printing of a dielectric and a second conductive layer. when a high voltage, at least 20v, and typically around 200-250v, is applied to the conductive layers, the device emits a short light pulse from the el layer. applying standard alternating current (ac) power allows this process to operate repeatedly, appearing as a continuous light source (smet, et al., 2010). the colour range of el inks is biased towards blues, greens and yellows. the brightness and colour of el inks may change relative to both voltage and frequency (song et al., 2018). in industrially-manufactured el products, the colour range can be extended through the use of dyes to change the colour of the light (silver et al., 2008). while there are exemplary works using el inks in architecture (kretzer, 2015), interaction design (franinović and franzke, 2015), interior design (loop ph, 2012) and product design (barati et al., 2018; olberding et al., 2014), their focus is on the process of creating non-textural and geometrical light-emitting patterns, using a single colour of ink, and/or methods for controlling the light. this leaves space for further research exploring the design potential of the raw material – printed el ink – in terms of expanding its colour palette and aesthetic range by experimenting with textile design methods – forming diverse colour mixtures, overprinting, and halftones. thus, this research aims to explore and exemplify the properties and potential of el inks as printable smart colours for textiles, in order to facilitate an understanding of designing complex surface patterns with el inks. the methods proposed by this research offer new resources for surface pattern designers to expand their creativity and craftsmanship in the printing design process. 2. set up for the experimental work the technique of silkscreen printing by hand was used to print the el inks directly onto a transparent, conductive surface (polyester film coated in indium tin oxide (ito film); gwent f2071018d1). the size of the silkscreen mesh was 43 threads per inch. the el ink was covered by a white dielectric insulator print layer (gwent d2070209p6), followed by a silver conductive print layer (gwent c2180423d2), producing an el device with a standard build per the manufacturer’s guidelines. this produces an el light emitted through the transparent substrate, meaning layers printed first sit at the top of the print when illuminated (figure 1). the print cannot be illuminated to assess the design outcome until all layers have been printed and dried. to see the light range, samples were illuminated within a range of 8vdc to 20vdc through a dc/ac inverter and viewed in darkness. colour measurements were also made in darkness, with a datacolor spyder5 colorimeter, using displaycal 3.8.7.1 software. five measurements of each sample were made, and outliers were calculated and discarded before the mean l*a*b* figures were calculated for each sample. it should be noted that the photos taken in a dark room were colour, texture, and luminance: textile design methods for printing with electroluminescent inks 29 color culture and science journal vol. 15 (1) doi: 10.23738/ccsj.150104 colour-managed to match as closely as possible the perceived appearance of the print when viewed in darkness. fig. 1: the standard build illustrated as printed. when illuminated, the device is turned upside down, and the light emits from the bottom, throught the transparent film. 3. design methods 3.1. colour mixing experiments were conducted using blue (gwent c2061027p15), green (gwent c2070209p5) and orange (gwent c2070126p4) print pastes. the colour palette was obtained with mixes of two-colour blends in 10% increments. each colour was also printed unmixed (100%), and a 1:1:1 (33% each colour) swatch was printed to test three-colour mixing. the result in daylight was a white print, however, once illuminated with an inverter at 20vdc and viewed in darkness, the effects were different coloured lights similar to mixtures of rgb lights: 80% green and 20% blue produced cyan, 20% green and 80% orange produced yellow light, and 80% orange and 20% blue produced magenta. the other mixes produced a smooth coloured light gradation. the 1:1:1 swatch appeared as a blue-green light and not white light. this is because white light is produced by the proper mixture of red, green and blue light. the green el ink is perceived as more toward turquoise, while the orange is far from red (figure 2). fig. 2: three colour scales produced by mixing two colours of el inks using blue, green and orange, illuminated with an inverter at 20vdc and viewed in darkness. the emitted light of each mixed colour was measured using the colorimeter, resulting in cie l*a*b* values for each colour (figure 3). while this provided useful information about the gamut and range of colours available through this method, the low l* (lightness) values of the colours did not represent them as they are perceived by the eye. in order to enable simulation as a design tool when using mixed el ink colours, an rgb value for each colour was sampled from the photograph of the colour mix print. these rgb figures have been given alongside the measured l*a*b* values in table 1. these can be used in graphic design software such as photoshop when designing and preparing patterns for el prints. this provides a visual representation of the colours achievable with particular combinations and gives the designer the ability to predict the result before starting to print. fig. 3: (a) the black triangle shows the gamut of the el colour mixture palette, with the dot indicating the 1:1:1 colour mixture. the srgb gamut is included (in grey) for comparison, and shows that the blue and green el colours and their mixes cannot be fully represented in an srgb environment (e.g., on-screen). (b) the cie l*a*b* colour system, used to measure the colour palette values. (c) the el colour palette mapped against *a and *b values (indicated in figure b by the gray square). colour, texture, and luminance: textile design methods for printing with electroluminescent inks 30 color culture and science journal vol. 15 (1) doi: 10.23738/ccsj.150104 colour l* a* b* r g b b100 12.47 -8.51 -29.9 167 208 253 b90g10 8.79 -9.02 -24.62 157 213 251 b80g20 15.53 -16.83 -27.02 154 219 248 b70g30 13.71 -19.99 -21.43 139 220 242 b60g40 15.97 -23.35 -20.92 131 221 236 b50g50 16.92 -28.59 -15.04 137 229 237 b40g60 17.83 -32.38 -14.34 136 236 234 b30g70 15.44 -31.54 -10.26 139 238 235 b20g80 23.18 -45.33 -5.03 147 244 232 b10g90 19.77 -41.13 -5.67 137 243 225 g100 11.63 -29.94 -2.64 90 227 194 g90o10 13 -30.73 -7.49 96 219 188 g80o20 8.55 -18.02 -3.3 100 207 176 g70o30 8.52 -18.83 -2.36 111 200 166 g60o40 6.05 -12.5 -1.62 92 144 114 g50o50 5.58 -10.63 -0.43 99 138 108 g40o60 8.25 -14.34 4.21 112 129 97 g30o70 6.08 -8.11 3.4 116 121 90 g20o80 4.58 -4.69 2.82 147 133 89 g10o90 1.6 -0.53 1.95 160 115 69 o100 7.64 6.2 12.46 209 113 0 o90b10 6.98 2.92 1.94 202 146 150 o80b20 14.66 2.88 -11.04 201 162 186 o70b30 11.16 0.88 -16.56 181 169 211 o60b40 10.29 -0.33 -16.8 177 175 219 o50b50 14.2 -1.37 -24.36 172 183 230 o40b60 15.31 -2.01 -25.37 174 194 238 o30b70 12.26 -3.62 -24.91 168 197 244 o20b80 17.68 -5.86 -31.21 169 201 247 o10b90 17.4 -8.37 -35.45 173 209 252 b33g33 o33 5.12 -7.73 -7.67 83 131 140 table 1: measured l*a*b* values, and suggested rgb values, for the el ink colour palette. 3.2. overprinting an overprinting experiment was conducted to test the potential for blending colours through overprinting the three unmixed, 100% el orange, green, blue inks. all possible two-colour overprints, including inversion of each overlap order, were tested, waiting for each layer to dry before printing the next. it was expected that the effect obtained by the overprinting of two different colours would result in a similar effect as if they were mixed equally and then printed. however, the results indicated that the printing order had a significant impact on the resulting colour when overprinting, with the top layer colour (printed first) dominating the resulting blended colour (figure 4). when the el prints were activated, they showed some errors such as unwanted particle gathering and uneven paste distribution that occurred during the hand-screen printing process. careful fabrication is thus important when planning and producing high quality designs. the results of this experiment guided the research towards exploring rasterization. fig. 4: there was a perceivable difference in green on top of orange and orange on top of green, for example; both combinations of orange and green resulted in a different coloured lights. 3.3. rasterization an experiment was conducted to determine the best resolution for rasterizing when printing with el inks. a stepped gradient, of 10% to 90% density, in 10% increments, was used to create ‘dot’ and 45° ‘line’ halftones, using 30, 25, 20, and 15 lines per inch (lpi). the result after activating the print indicated that the dot halftone had clear definition at low densities, across the range of resolutions from 30 lpi to 15 lpi. the 45° lines, however, were only clear at 20 and 15 lpi, even at low densities. the results of this experiment suggest that coarser resolutions of 15 or 20 lpi are more effective for producing detail, and that either only two or three densities should be used, or lower densities than were tested, to ensure visible differences between areas (figure 5). colour, texture, and luminance: textile design methods for printing with electroluminescent inks 31 color culture and science journal vol. 15 (1) doi: 10.23738/ccsj.150104 fig. 5: the result of the rasterization experiment. two experimental sets were conducted to evaluate colour mixing through halftone rasterization, again using the three print paste colours unmixed at 100%. these were split into two colour groups: analogous colours – blue followed by green – and complementary colours – orange followed by blue. the first set (figure 6, prints 1 and 2) was made using the 20 lpi dots, 15 lpi lines, and 15 lpi dots, each at 10% and 20% density, with the screen slightly offset so the two colours did not overlap and would mix optically. the second set (figure 6, prints 3 and 4) used the same rasterizations for the first colour layer, however, the second colour layer was printed with 30% and 40% density, turning the screen 180°, so the 15 lpi dots were covered with 20 lpi dots and vice versa. the result indicated that colour mixing using rasterization is different to colour mixing through overprinting the two colours or mixing the two colours. for instance, the colour mixing of 10% blue and 40% green in print number three appeared equivalent to the 20% blue and 80% green (b20g80) mixture in figure 2, and these were equal in terms of colour proportion but they represented two different coloured light mixtures (figure 6). 4. result 4.1. designing surface patterns using el after understanding how el inks behave and how this may impact the design process, a set of surface patterns inspired by a twill woven fabric and two knitted textiles featuring patterns of dots and lines were designed, with the aim to exemplify how the different methods for colour mixing developed by this research can be used when forming a design. the surface patterns were designed as two-screen prints using photoshop consuming data from table 1, and aware that the colours of positive and negative spaces were reversed in darkness (kooroshnia, 2014). fig. 6: three-dimensional effects were observed in all the prints. in prints 3 and 4 moiré effects were created due to the interaction of the different rasterization lpi values for the two overlapping colours. two pairs of colours were selected from the colour mixing experiments. design 1 used 100% blue (b100) el ink in the first layer and a mix of 20% green with 80% orange (g20o80) for the second layer. design 2 used 100% green in the first layer (g100) and a mix of 20% blue with 80% orange (b20o80) for the second layer. design 3 was printed with a mix of 20% blue with 80% green (b20g80) in the first layer, and a mix of 20% blue with 80% orange (b20o80) in the second layer. to enhance the textural expression of the printed el patterns the technique of halftone rasterization was used with the aim to mimic the visual effect of surface patterns printed on textiles. likewise, to enhance the colour palette, the technique of overprinting was used to create complex colour mixtures as visual effect in both the foreground and background of the designs (figure 7). the results were compared to the sketches made in adobe photoshop. the printed el patterns demonstrated that visual effects such as complex color mixtures, form intervals, perception of movement, and spatial illusion can be achieved through printing with el materials. these effects occured mainly because a combination of dim and bright coloured lights resulted from the overprinting. colour, texture, and luminance: textile design methods for printing with electroluminescent inks 32 color culture and science journal vol. 15 (1) doi: 10.23738/ccsj.150104 fig. 7: designers can use el inks to print light-emitting surface patterns, using the same methods used for surface pattern pastes. from left to right: designs 1, 2 and 3. 5. discussion by demonstrating the potential of el inks when approached using textile design methods for printing such as colour mixing, overprinting, and halftone rasterization, this research expands the design possibilities of el crafted displays in producing a novel, coloured, rich textural character to light as a material for surface design. we suggest digital rgb values for mixed colours, enabling computer simulation of designs, removing some of the risks from this technique, and freeing designers from the flat, monochromatic designs that characterize current el offerings. the experiments were evaluated in a dark room using an ac/dc inverter supplied with a variable direct current (dc) power supply to illuminate the prints. stepping the dc voltage through 20v, 16v, 12v, and 8v dimmed the coloured lights, creating an illusion of space in the surface pattern (figure 8). fig. 8: illuminating the prints with 8v creates the dimmest coloured lights and 20v creates the brightest coloured light. in addition, while el printing typically produces static colour, it can be used in the design of segmented displays to produce transformative digital textiles with temporal variations through changes in brightness (i.e., through variable voltage sequencing) and as such offers an alternative to complex multi-led arrays, or the linear restrictions of optical fibre. it has the potential to open new territory in textile design for flexible, luminous, and dynamic textile displays with complex textures and surface patterns and temporality. recent research in material engineering has proved it is possible to print basic el inks directly onto textiles, maintaining their intrinsic flexible properties to create functional lighting surfaces (verboven, et al., 2018). from a design perspective, the replacement of plastic substrate with textiles demonstrates more expressive potential by enhancing the haptic perception of the printed patterns. however, more cross-disciplinary research is needed to be able to combine the two perspectives into the development of aesthetic and functional products. this research mirrors the led-based work of mueggler zumstein et al. (2016), in providing colour reference tools to enable textile designers to approach designing with smart materials. in daily life, we are used to communicating and being surrounded by visual and haptic displays which are hiding complex technologies. by proposing methods to create complex surface patterns with enhanced colours and textures, the result of this research suggests more creative ways to express smart technologies for the automotive or home environments when designing displays with tactile and visual feedback. likewise, el printing as applied in product design or architecture offers as a design asset the familiar expression of textiles. this could provide an interface for lighting technology which might enable alternative ways to experience peripheral information or adapt interior atmospheres to ensure well-being. colour, texture, and luminance: textile design methods for printing with electroluminescent inks 33 color culture and science journal vol. 15 (1) doi: 10.23738/ccsj.150104 6. conclusion the experiments conducted during this research suggest that the print potential of el inks is wider than has been explored in art, design and research so far. even with the limited colour range of commercially available el inks, broader aesthetic and textural expressions are possible than the typical flat blue of the technology to date. textile craftsmanship and design methods such as colour mixing, halftone rasterization, and overprinting may be applied to electroluminescent inks, and the design potential of these techniques can be used to produce light-emitting smart textiles, where the intangibility of light combines with the physicality of textiles to define a hybrid category of expression. 7. conflict of interest declaration no financial/personal interests have affected the authors’ objectivity(s). 8. funding source declaration this research project has been funded by the smart textile initiative at the swedish school of textiles, university of borås, sweden. 9. short biography of the author(s) delia dumitrescu is professor in textile design at the swedish school of textiles. her research focuses on the development of smart textile design methodology and how smart textile design methods can be expanded to related design fields with the aim of developing crossdisciplinary practices. marjan kooroshnia is a colour researcher and associate professor at the swedish school of textiles. her phd research explored the design properties and potentials of thermochromic colours printed on textiles in order to expand the range of colour-changing effects and to facilitate communication regarding, understanding of, and designing with, these smart materials. erin lewis is a phd researcher in textile interaction design at the swedish school of textiles. her research explores electromagnetic textile expressions in the form of interactive, wearable, and ambient textile prototypes. kathryn walters is a phd researcher in textile design at the swedish school of textiles. her research area includes complex woven structures and changeable textile materials. licensing terms articles published in the “cultura e scienza del colore -color culture and science" journal are open access articles, distributed under the terms and conditions of the creative commons attribution license (cc by). you are free to share (copy and redistribute the material in any medium or format) and adapt (remix, transform, and build upon the material for any purpose, even commercially, under the following terms: you must give appropriate credit to authors, provide a link to the license, and indicate if changes were made. you may do so in any reasonable manner, but not in any way that suggests the licensor endorses you or your use, you may not apply legal terms or technological measures that legally restrict othersfrom doing anything the license permits. copyright: the authors keep the rights to further publish their contents where they want and can archive pre-print and post-print (submitted version and accepted version) and the published version of the pdf of their article with no embargo period. references addington, d. m., & schodek, d. l. 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(2018). printing smart designs of light emitting devices with maintained textile properties. journal of materials, vol.11(2), 290. 27 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130203 color and materials in design didactics. design of a playroom and relaxation area for children – case study anna kmita, phd department of design, academy of fine arts katowice, poland annakmita@gmail.com, akmita@asp.katowice.pl abstract this project was focused on providing design students with practical knowledge regarding the use of colors and cmf (color, material, finish) implementation in public space, interior, and product design. in cooperation with a textile company, they designed a space at the day care center where children and teenagers were able to relax and participate in therapeutic meetings and conversations. during project, students became familiar with the ways of defining colors and their symbolism (moodboards, graphs, semantics), cmf design, influence and use of taints in interiors (simulation of perception in different light conditions, panton viewing booth light box), parametrization of coloring (ncs, pantone, ral, cmyk). the color scheme was elaborated in the process of consultations with experts and psychologists and executed with the participation of users of the facility. the idea also involved introducing young people to interesting places in silesia. this purpose was served by the wall map of the region and original seats, which featured the landmarks marked on the map. the added value of this project was presenting students with the opportunity to work with an actual business (textile producer). this involved learning about the technological background, organizing dedicated workshops and consults with experts, and the possibility of working with materials provided by the producer. the implemented project is an example of a model program of cooperation between representatives of higher education – academy of fine arts and design in katowice and a public utility institution – community day care center at the gniazdo foundation. keywords color and design, cmf, color and education, psychological aspect of color received 21/03/2021; revised 04/05/2021; accepted 13/08/2021 color and materials in design didactics. design of a playroom and relaxation area for children – case study. 28 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130203 1. introduction this article presents the findings of an educational project concerning colors design and cmf (color, material, finish) implementation in public space, interiors, and product. the academy of fine arts in katowice conducts research and didactic program regarding color design. during lectures, case studies and practical assignments, students acquire basic knowledge and skills at parametrization and design of color. fig. 1. didactic program at afa katowice (color design). 2. project within the design and didactic activity, a pair of students executed a project of an unusual playroom and relaxation area for children and teenagers of the katowice community day care center at the gniazdo foundation (fundacja gniazdo, 2021). the project was carried out in collaboration with a textile producer, lech fabrics company (multimedia, 2021). in accordance with the notion of corporate social responsibility (ideo, 2015, 29), it assumed a purposeful participation of the company in young designers’ education as well as improving a fraction of the world for a group of local children in the silesia region. 2.1. the premise of cooperation the headquarters of lech fabrics company, the leading importer and producer of fabrics, is in kostrzyn, wielkopolskie voivodship, poland. there, one can see their modern offices, a showroom presenting their upholstered furniture and a warehouse of 14 thousand square meters. lech fabrics was chosen as a didactic partner of the academy of fine arts and design due to its 40 years’ experience and technical potential as well as its values. it is a family business, oriented towards social activity, sharing knowledge and experience with young designers. the cooperation between the academy and this business partner involved a series of trainings and presentations of possible fabrics application as well as cooperation in terms of production and implementation of the designed product. the company granted students’ access to technological facilities, organized dedicated workshops and expert consultations of fabric designers regarding the selection of colors for the interior. the producer made its fabrics available to students as well. their knowledge about color sampling and designing color tendencies was expanded by the product range offered by the brand. students found the entire process especially motivating due to the fact that their efforts were purposeful, oriented towards the result in the form of guaranteed application, rather than abstract student practice. beside the possibility of their design being implemented, recognized and rightfully rewarded, both designers and producers were encouraged by the social aspect of their work – helping children and teenagers from the community day care center at the gniazdo foundation. the designed interior provided these young people with a good space to read books, study, relax, conduct therapeutic meetings and meaningful conversations in small groups. stages of the design process resembled those of classical service design (brown, 2009, 45–63) in permanent contact with the future users and the support of experts (representatives of the interior design industry). one could distinguish:  building of the team and mutual inspiration:  creating the team consisting of students, academy teachers, employees and pupils of the gniazdo foundation, employees and experts of lech fabrics;  defining areas of cooperation and users’ needs during workshops;  didactic workshops for academy students led by lech company;  workshops with the users (listening and forming the hierarchy of needs, drafting mood boards of ideal space, presentation of possibilities, arrangement of space, inspiration);  interviews with foundation employees and psychologists providing for designing in compliance with the users’ needs.  generating ideas and prototyping regarding the service and the project:  creating space mock-ups, color and fabric models;  building usage processes;  building and research of functional areas of the selected space; color and materials in design didactics. design of a playroom and relaxation area for children – case study. 29 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130203  colors research (perception of colors on fabric and the walls in changing light conditions);  studio visits in the manufacture and poznań fairs.  verification of the project:  contest method of displaying designed solutions;  modeling and prototyping;  technological consultations with the producer (implementation);  common application of the project in space (implementation involved pupils, employees, students) building community and shared responsibility for the project. 2.2. methodology in the process of students’ projects development, where the conducted analysis translates onto the project concepts, a triple diamond methodology is often used (design methods step 1: discover, 2021). developed by design council, it consists of 4 stages: discover (analyses, documentation, interviews), define (organizing information, building the brief), develop (design development, prototyping and testing) and deliver (implementation). this allows to organize the design process following the sequence: possibly the widest scope of analysis – drawing and formulating conclusions – return to unrestricted prototyping and building precise design concept. the working group, consisting of the author and students conducting the experiments, used the following design methods: a. defining the symbolism and taint (moodboards, graphs, semantics); b. choice of color, materials and finish (cmf); c. testing the effect and use of particular taints in interiors (simulation of perception of taint and fabrics in different light conditions by means of panton viewing booth light box); d. parametrization of coloring (ncs, pantone, ral, cmyk). 2.2.1. defining the symbolism and taint (moodboards, graphs, semantics) a group of students, assisted by a technologist of lech fabrics, created color moodboards that constituted the base for further project. a moodboard is a design method and creative tool which allows to define the character of project by visualizing its general concept (stramer, 2007, 29). they also worked with a semantic differential, which is a type of rating scale designed to measure the connotative meaning of objects and concepts. on its opposite axes, a spectrum of contrary features is located, e.g., traditional – modern, everyday – festive, glossy – mat, chromatic – achromatic. students situated their project objectives in a chosen area of the spectrum built on these features. to define the features for the spectrum and the context of the project, they created a mind map – a diagram used to visually organize information. emphasizing the semantic aspect of design makes one aware of the effect that its basic properties (shape, material, texture, color, size) have on the users’ psychophysical and physical response. in the design process, these properties serve as variables and determine the form of design. fig. 2. using a moodboard for defining the design color scheme. 2.2.2. choice of color, materials, and finish (cmf) the accurate selection of color, materials and their finish greatly influence the functional aspects of a designed product and its final appearance. all the properties are interdependent, and their configuration affects the entire design. color perception results from many factors classified by the optical society (osa) as early as 1943 (zausznica, 1959, 357–360). they are known as attributes (properties) of color perception and include i.e. brightness, tone, and saturation, but also: size, shape, location, fibrillation, scintillation, transparency, luster, glow. this classification was the first attempt to expand the three basic parameters by additional factors – the basis of the current cmf design. it must be noted that none of these aspects should be considered separately from the others. considered all together, they allow to accurately define the character of a given color. in the project, matching the coloring and materials to the users’ needs followed from consultations and was conducted with the support of lech fabrics experts. they color and materials in design didactics. design of a playroom and relaxation area for children – case study. 30 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130203 assisted students in solving design problems by applying appropriate materials and technologies. enabled by the possibility of using a wide palette of fabrics made available by the producer, students could analyze every cmf aspect and become aware of their effect on the project. the method of evaluation of individual factors (color, material, finish) and their influence on the recipient was visualized by means of the c/m/f indicator (becerra, 2016, 49) which allows to understand the significance of each element in the following aspects: functional / emotional attributes, quantitative facts, performance / aesthetic requirements, characteristic keywords. 2.2.3. influence and use of taint in interiors (simulation of perception of taint and materials in different light conditions by means of panton viewing booth light box) the choice of colors was elaborated in the process of consultations with experts and psychologists and carried out in the participation process with users of the day care center. the process included taking pictures of specific color combinations in the context of particular spaces, choice of materials and temperature of light, and accounted for the color preferences indicated by the users. students made coloring samples and used them for several simple experiments to observe the correlation of change of lighting and color impression depending on the type of object (flat / three-dimensional), kind of pigment (print, acrylic paints) and the substrate (paper, textiles). the first analysis concerned observing the chosen color on a simple three-dimensional object (cube). it was intended to make the young designers aware of the difference in appearance of the tested taint when used on the 3d rather than flat surface. the next experiment regarded the selected set of wall acrylic paints. the observation of how natural light influences color perception in the interior was expanded by testing the color samples in the panton viewing booth light box. another analysis, carried out in the same conditions, used the selected fabric samples from the palette of materials provided by the producer. due to different types of light in the interior (natural daylight, artificial light: neutral and warm), students were able to observe the phenomenon of metamerism on all tested surfaces, textures, and color variants. this experiment helped them understand the design issue of appropriate lighting of color on textiles and acrylic paints. the described analysis was intended as observation and visual experience of the changes without taking measurements or cataloguing the results. such an approach allowed the young designers to learn how to correlate and evaluate fig. 3. simulation of specific light conditions for selected color samples. fig. 4. simulation of specific light conditions for selected fabric samples. color and materials in design didactics. design of a playroom and relaxation area for children – case study. 31 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130203 selected components of the future design and provided them with tools to verify or validate their intuitive ideas and individual preferences. general description of research conditions: selected components of the future design and provided them with tools to verify or validate their intuitive ideas and individual preferences. photographs of samples were taken with a digital camera equipped with the full frame matrix type cmos, without low-pass filter, factory-calibrated. there were fixed settings of exposure in every photograph, 100 iso, f/14, ¼ sec. the balance of white in the camera was 5000k (daylight, d50). pictures were taken in a darkened room, samples were lit only with panton viewing booth light box, using the following light sources: 1) daylight (d50) color temperature 4990k, fluorescent lamp with light intensity 2120lx. 2) store 1 (cwf) color temperature 3806k, fluorescent lamp with light intensity 1625lx. 3) store 2 (tl84) color temperature 3980k, fluorescent lamp with light intensity 1921lx. 4) home (inc a) color temperature 2847k, fluorescent lamp with light intensity 1299lx. measurements of color temperature and intensity for light source installed in the device (panton viewing booth light box), were provided by the producer. adobe rgb was chosen as the color space of saved files; neither postproduction nor digital editing were conducted. the above conditions of experiment record allowed students to observe the color temperature of the selected light source in comparison with natural daylight (d50) and its influence on perception of the color of materials used in the study, as well as the difference of light intensity between particular light sources. the device parameters, which determined the type of lighting, were selected for the most precise imitation of the actual changes of light color in the designed interior (daylight, and warm/neutral artificial light). experiments conducted by students focused on cognitive aspects and were their first experience of changes in color depending on the lighting parameters. this research, therefore, carried a good didactic value for the young designers. 2.2.4. parametrization of coloring (ncs, pantone, ral, cmyk) the project of an unusual playroom and relaxation area for children and teenagers of the katowice community day care center at the gniazdo foundation required from students the parametrization of selected elements (furniture, walls, fabrics, finish) according to the nomenclature of numerous color standards. color mapping applies various theoretical models and color charts. developed individually, they currently cofunction on the market of interior, product and visual communication design. the previously assigned areas, typical of each individual chart, are becoming increasingly composite. for instance, charts typically used in polygraphy, now have their variations dedicated to textiles; those characteristics of the paint industry, have expanded their use and are now applied in parametrization of the coloring for plastics and advertising materials etc. therefore, regardless of the substantive content of the project, every designer should master the use of any type of color chart and be able to correctly transpose the selected color values as accurately as possible. a real challenge of the project documentation can be indicating a particular, uncharacteristic color, which could be closely defined by means of all the abovementioned notation standards. in the case of this project, the students team had to define the color scheme for the color sets of wall paints, wood varnishes, plastic elements, textiles. they applied the systems of ncs (ncs colour – universal language for colour commmuication, 2021), pantone (pantone colour, chips & colour guides | colour inspiration | pantone uk, 2021) and ral (erleben and farben, 2021). among those three, only ncs could be considered as a color model organized and described in a manner characteristic of such compilations (munsell color system, ostwald model etc.). pantone and ral are charts of ready color recipes used in design. this experience provided students with a good and thorough training of color charts use and color translation between the charts. beside designing the color scheme of the room, the idea was to present interesting places in silesia and thereby familiarize young people with history, build the identity and community of place, as well as spark their imagination. this purpose is served by the wall map and original seats, which present places marked on the map. the resulting color layouts are composed of illustrations and characteristic typography, applied to natural fabrics and wood. employing various variants of textiles (padded furniture, decorations, panel partitions, curtains etc.), the entire project responds to the functional needs of its users. color and materials in design didactics. design of a playroom and relaxation area for children – case study. 32 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130203 fig. 5. project of workplace. matching materials and colors to the function of an interior. fig. 6. project details. textile elements, featuring original prints, dedicated to the relaxation area. there were many aspects directly connected with the need for modification of the interior’s function depending on the time of day, number of participants and the character of classes conducted in the room. the functional layer of the project assumed a selection of colors to allow the intensive use of the work area by several children (easily cleaned and durable materials, neutral color scheme) as well as effortless reorganization of the furniture and shelves (frequent touching). attention had to be paid also to the psychological aspect in reference to the relaxation area and therapy (using natural materials, pleasant to touch, calming color scheme). the project allowed for personalization of the interior by children (textile boards with their drawings and modular poufs with interesting visual components). the interior design included original elements, such as seats combining the features of comfortable ottomans with didactic materials (each seat bears an original print and information about an important monument of silesia or an interesting place), and the wall covered in a textile map, on which children can mark the landmarks visited in the region. the final color scheme was developed in consultation with experts and psychologists and executed in participatory process with the users of the facility. children articulated the need for “their own” private space, which would resemble a well decorated house rather than specialist group therapy rooms. as a result, the team of young designers and experts had to face various challenges and meet diverse expectations. 3. conclusion the project aims to promote the creative and innovative solutions, using textiles in public spaces, in reference to interior color design. its added value was presenting students with the opportunity to work with an actual business (textile producer). this involved becoming familiar with technological background, organizing dedicated workshops and consults with experts, and the possibility of working with materials provided by the producer. the knowledge regarding color charts and designing color tendencies was acquired in the practical context of the product range offered by a particular brand. the project was implemented by the end of 2019 and nominated for the śląska rzecz 2020 – silesian icon 2020 award (gołębiowska. e., 2020, 86–87) in the service category as an example of a model program of cooperation between representatives of higher education and public utility institution. 4. conflict of interest declaration the author declares no conflict of interest related to this publication. 5. funding source declaration this research did not receive any specific grant from funding agencies in the public, commercial, or not for profit sector. 6. acknowledgment for all authors and other person who was supported this project: sonia łuszczyńska, martyna pluczyk, mateusz mioduszewski, piotr sabatowski, jarosław gwizdak, gniazdo findation, lech fabrics company. color and materials in design didactics. design of a playroom and relaxation area for children – case study. 33 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130203 7. short biography of the author. anna kmita graduated from the academy of fine arts in katowice, majoring in design. habilitation: “a set of three projects related to color design in visual communication”. she leads research and design programs focused on heritage and restoring forgotten elements of design, history, culture, and identity of silesia. the programs ended with publications and implementations of results in cooperation with the local businesses. 8. references becerra, l., 2016. cmf design. amsterdam: frame publishers. brown, t., 2009. change by design: how design thinking transforms organizations and inspires innovation. new york: harpercollins. design council. 2021. design methods step 1: discover. [online] available at: <http://www.designcouncil.org.uk/newsopinion/introducing-design-methods> [accessed 7 june 2021]. erleben, f. and farben, a., 2021. alle ral farben | ral farben. [online] ral-farben.de. available at: <https://www.ral-farben.de/alle-ralfarben> [accessed 7 june 2021]. fundacja-gniazdo.org. 2021. fundacja gniazdo. [online] available at: <http://fundacja-gniazdo.org/index.php?id=swietlica> [accessed 7 june 2021]. gołębiowska, e., e., 2020. silesian icon. cieszyn: zamek cieszyn. ideo. 2015. design thinking for libraries. textbook of user-centered design information. [online] society development foundation. available at: www.designthinkingforlibraries.com [accessed: 1 june 2021]. multimedia, e., 2021. start. [online] lechfabrics.com. available at: <https://www.lechfabrics.com/pl/home-start> [accessed 7 june 2021]. ncs colour. 2021. ncs colour – universal language for colour commmuication. [online] available at: <https://ncscolour.com> [accessed 7 june 2021]. pantone llc. 2021. pantone colour, chips & colour guides | colour inspiration | pantone uk. [online] available at: <https://www.pantone.com> [accessed 7 june 2021]. stramer, a., 2007. jak dobierać kolory. warsaw: arkady. zamek cieszyn. 2015. design in public space. change. cieszyn: zamek cieszyn. zausznica, a., 1959. nauka o barwie. warsaw: pwn. video documentation of the project: https://www.facebook.com/391765764330507/videos/26499851550196 64 84 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130210b umbrella diagram: 1981-2021, five decades of forecasts and cmf design clino trini castelli 1 1 castelli.design, work@castellidesign.it corresponding author: clino trini castelli (work@castellidesign.it) abstract the umbrella diagram, developed by clino trini castelli since 1978, is a fundamental tool to configure cmf design languages and forecast historical color and material trends survey. the tool, based on decades, is represented by arches instead of an evolution of a timeline. this cyclical progress proved to be premonitory of the strong changes observed between the color languages of the decades. the umbrella shape of the diagram stems from the coexistence of large arches (historical trends) with smaller arches (fashion trends), frequently in conflict. castelli first turned to the past of the 70s, 60s and 50s, testing his format backwards based on what was already observed. he then applied the same principles and parameters, looking rather at the 1980s and, till today, to the other four upcoming decades. the umbrella diagram was conceived as a proprietary tool of castelli design and reserved for his international customers and educational activities. keywords cmf design and forecasting, iconic colors, syntactic colors, color presence, color distribution received 18/10/2021; revised 08/11/2021; accepted 10/11/2021 umbrella diagram: 1981-2021, five decades of forecasts and cmf design color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130210b 85 1. introduction this of the aic 2021 milan congress is the first public presentation of the umbrella diagram executed outside of a professional or educational confidential context. despite the current presentation of this proprietary tool is taking place exactly forty years after its creation (19801981), to this day continue not to be any web recurrences on search engines, except one not-authorized imitations that appeared several years ago using the same graph and the same four basic parameters. intending to take over the design company cdm consulenti design milano, clino trini castelli had already begun, in 1978, the search for a tool that would make it possible to predict the identity of colors and materials languages in advance, as well the related trends. with the advent of the additive color synthesis era (then completely unnoticed) castelli founded and directed the colorterminal ivi in milan (1978). the colorterminal was the first color research center for design and architecture in the world, enabling the chromatic potential discover of the additive rgb synthesis. the umbrella diagram was going to be a new dialogic tool like the gretl’s diagram (1977) now in the cci collection of centre pompidou in paris proper for guiding and training also the designers of the first international customers by castelli design, including louis vuitton. with cdm, founded in 1974, castelli introduced the “extensive vision” of the metaproject in the professional field through the design primario, this in opposition to the “intensive vision” of traditional design process. this had led to the development of qualitative aspects of modernity which was still unsolved, as evidenced by the success of the colordinamo and decorattivo manuals of the centro design montefibre (1974-1978). figure 1. the umbrella diagram graph with small and large arches inspired by the kircher’s diagram (1646). umbrella diagram: 1981-2021, five decades of forecasts and cmf design color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130210b 86 figure 2: the umbrella diagram chromatic nature: syntactic color vs iconic color. in the cdm consulenti design milano, beyond clino trini castelli, andrea branzi and massimo morozzi, also participated for a while the architects ettore sottsass and alessandro mendini. since 1980 the international activity of castelli design with vitra in europe, herman miller in the usa and mitsubishi in japan has pointed to a great development of cmf design (colors, materials and finishes), an acronym born in 1981 with the cmf project for herman miller by clino castelli. umbrella diagram graph: − color arches (historical trend arch, fashion trend arch). − time lapse (run-out or deviation: anticipation or delay from the ideal historical trend). the umbrella diagram graph (figure 1) is derived from the interlaced arches of kircher’s diagram (1646) published on the art magazine data arte. the article i diagrammi del colore: trini castelli (1978) describes the evolution of the color diagrams found in ancient books and other documents provided to the colorterminal by faber birren, the founder of the yale university color library, with which castelli had begun to collaborate since 1977. the umbrella diagram is a tool based on decade divisions, represented by large arches instead of the classic linear evolution of a timeline. the main idea was to connect a precise historical color language to a decadic trend, already started from the 50s. this cyclical progress proved to be premonitory of the strong changes observed between the languages of the various decades. the umbrella shape of the diagram derives from the coexistence of large arches (historical trend) with smaller arches (fashion trends) that develop, often in conflict with the historical trend of the overlying decade: raimondo (1982). umbrella diagram: 1981-2021, five decades of forecasts and cmf design color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130210b 87 when clino castelli developed the diagram, starting from 1978, he first turned to the past of the 70s, 60s and 50s, testing the format backwards based on what was already known. he then applied the same principles, looking instead at the 1980s of the upcoming decades, thus anticipating the great novelty of post-modern and memphis polychromatic languages, with their syntactic and tonal colors: lentati (1984). the qualities that make the umbrella diagram tool dialogic and peculiar stand in a specific articulation of the factors of judgment and evaluation of the inherent nature of color (such as: iconic color / syntactic color) (figure 2), on the chromatic characteristics of the colors in use and their application on objects and environments (such as: color presence / color distribution) (figure 3). these factors are always connected to the social, economic and technological contexts of the individual decades (such as: socioeconomic context / technoscientific context). umbrella diagram’s original chromatic parameters (table 1) and context: − chromatic nature (iconic color, syntactic color) − chromatic features (color presence, color distribution) − historical context (socioeconomic context, technoscientific context) 2. umbrella diagram’s historical trend identities the entire umbrella diagram historical trends identities show a sharp decadic opposition jump between the chromatic nature languages (figure 4), that are alternatively iconic and syntactic. this is probably due to the need to reach the maximum possible sensation of chromatic novelty. figure 3: the umbrella diagram color distribution feature. “the gentleman and the rascal”: paradox effect of inverted color distribution on a same black & white color presence. umbrella diagram: 1981-2021, five decades of forecasts and cmf design color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130210b 88 table 1: all the parameters seen simultaneously with a hint on 20s decade, that marks the end of the modernity. figure 4: the umbrella diagram color language evolution graph that show the alternation of chromatic nature. umbrella diagram: 1981-2021, five decades of forecasts and cmf design color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130210b 89 figure 5: the eighties color trend with tonal and syntactic languages. figure 6: the incoming decade of the nineties with the second ecologism created a strong mutation of the color trend in relation to the eighties. umbrella diagram: 1981-2021, five decades of forecasts and cmf design color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130210b 90 3. author’s statement on the umbrella diagram “[...] we analyze trends with an umbrella diagram based on decades, which i elaborated at the end of the seventies in order to look back and to look into the future. this diagram is something very important for me [...]”: mitchell (1996: 68). the diagram format and images were closely linked to the issues that could interest my customers, as the field of new materials (europe, japan), automotive production and related cmf languages: takehara (1984) (japan, europe, usa), large office systems (europe, usa, japan, australia), office equipment, including large servers (europe, japan), etc. this meant, for example, that for each decade was selected a formula 1 racing car because, in addition to having a livery suited to the emerging color schemes of the moment, in most cases was also potentially the winning stable. in addition to the second ecologism of the nineties: trini castelli (1995), where color distribution (metachromatic) became irrelevant, the umbrella diagram has also highlighted the natural and achromatic experience of the first ecologism of the seventies (club of rome, 19681973) to which i actively participated in its promotion with the magazine domus. however, the most sensational anticipation came with the publication of the book transitive design: trini castelli (1999) and the presentation of the languages of the zero years of the new century where instead the duality of color distribution (heterochromatic) became relevant again. transitive design also anticipated the visions of transmodernity that anticipated the great ecological transition that began after the current global crisis due to the pandemic. this crisis was somehow anticipated by the alarming emergence of the dissonant harmonies, the extreme languages and hyperchromatic colors of the 10s. the umbrella diagram has been doubly important to me because over time it has allowed to maintain constant attention to certain signals coming from human ambitions and emotions connected to the global “sentiment of color”. this is how i had the certainty of having definitively emerged from what was the long and extraordinary human experience of modernity, to now enter in the 20s of transitive times floating season. 4. conflict of interest declaration the authors declare that there is no any conflict of interest concerning the content of this article. 5. funding source declaration this paper did not receive any specific grant from funding agencies in the public, commercial, or not for profit sector. 6. short biography of the author clino trini castelli (b. 1944) designer, artist and design theorist lives and works in milan. internationally known for cmf design (color, material and finishes) of which he was the initiator, castelli introduced the "no-form" renewal of plastic languages applied to industrial products through the tools of design primario. as opposed to traditional compositional methods, clino trini castelli has focused on the design of the more intangible aspects of figuration, like color and material, light and sound, emphasizing the virtues of a sensorial approach to art and design. since the early 1970s this has made him a pioneer in research on the emotional identity of products in the industrial sector. his work has received important european, american and japanese prizes, including two adi compasso d’oro awards. 7. acknowledgment special thanks to: esperanza nunez, antonio petrillo, claudia raimondo, anna barbara, paolo lorini, manuela bonaiti, daniela domina. references lentati, g. 1984. il colore in versione tonale policromatica. ufficiostile 1: 44-45. mitchell, t. c. 1996. new thinking in design: conversations on theory and practice. new york: van nostrand reinhold. raimondo, c. 1982. la tendenza tonale e il colore negli anni ’80 (intervista a clino t. castelli sui trend). supplemento interni annual ’82 – colore, interni 316: 8-13. takehara, a. 1984. the philosopher of color clino castelli. car styling 48: 13-36. trini castelli, c. 1978. i diagrammi del colore. data arte 31: 12-17. trini castelli, c. 1995. at the native state: rise and destiny of the ecological product. in: design of amenity. selected paper of international symposium. aa.vv., ed. kyushu: university press, 464 468. trini castelli, c. 1999. transitive design: a design language for the zeroes. milano: electa. 7 color culture and science journal vol. 14 (2) doi: 10.23738/ccsj.140201 colours, light and well-being: characterizeation of chromatic phenomena in collective housing. lorrain caumon 1,2,3 , estelle guerry 1,2 , georges zissis 1 , céline caumon 2 , elodie becheras 2 , christelle infantes 3 1 laplace, umr5213 (cnrs, inpt, ut3), université toulouse iii, france; lorrain.caumon@laplace.univtlse.fr , estelle.guerry@laplace.univ-tlse.fr , georges.zissis@laplace.univ-tlse.fr 2 lara seppia, ea 4154 (ut2j), université toulouse ii, france ; celine.caumon@univ-tlse2.fr, elodie.becheras@univ-tlse2.fr 3 sobrim company haranam concept, bayonne, france; contact@sobrim.fr corresponding author: lorrain caumon (lorrain.caumon@laplace.univ-tlse.fr) abstract the objective of the study presented is to demonstrate the interest of chromatic and luminous analysis of a place in the pre-design phase. this analysis protocol is in line with the designer's ethic, which is to anticipate and respond to the conscious and unconscious needs of users, thus participating in the construction of a quality approach. based on the case study of the "bonamour" project (capbreton, france), we question the value and interest of promoting a protocol that favours a benevolent and differentiated design approach. this will allow us to evaluate the relevance of the devices applied. in the end, the data collected and the recommendations applied to the project will allow property developers to progressively turn towards a more inclusive and sensitive design of lighting and colours applied in the residential sector. keywords (light design, color design, visual comfort, protocol, accompaniment) received 11/16/2021; revised 25/05/2022; accepted 13/10/2022 mailto:contact@sobrim.fr mailto:lorrain.caumon@laplace.univ-tlse.fr colours, light and well-being: characterize-ation of chromatic phenomena in collective housing 8 color culture and science journal vol. 14 (2) doi: 10.23738/ccsj.140201 1. introduction 1.1 health and housing threats the recent pandemic we have suffered is the sixth to hit humanity since the spanish flu of 1918. according to onu report, the frequency and severity of these global epidemics could accelerate in the coming years, due to our lifestyles and the incredible adaptability of viruses (intergovernmental science-policy platform on biodiversity and ecosystem services (ipbes), 2020). in this exceptional health context, we have seen that housing conditions have had a greater impact than ever on our daily lives. we therefore realised that the problems linked to the quality and sharing of collective living spaces during a pandemic will be major issues in the future and will require the full attention of real estate professionals. all the more so for many reasons, staying at home can be accompanied by multiple and varied disabilities, thus affecting quality of life (eideliman and gojard, 2008), (piccoli et al., 2020), (onu, 2020). in france, approximately 12 million people are affected by a disability, including 1.5 million by a visual impairment and 850,000 by reduced mobility, (mormiche, 2001). age is also a factor to be taken into consideration, as in 2050, metropolitan france will have about 70 million inhabitants, of which more than a third will be 60 years old, (brutel, 2002). for all these people, the positive and reassuring perception of the daily environment must become an important issue. it is therefore necessary to adapt the environment of collective housing to people with different pathologies and their potential consequences on their habits. 1.2 chromatic effects and methods of approach. with this study we want to provide reflections on design issues such as the design of sensitive and inclusive built spaces. to do so, we focused on what inclusion means in creating the atmosphere of a place through its influences of colour and light. to this end, we defined that an inclusive atmosphere translates into situations of sensitive interactions understood as the plural and singular experience one has of a given place at a given time, influencing our sensations and quality of life. for many years, designers and authorities have been placing people and their plurality at the heart of architectural projects, based in particular on guides such as the well building standard (‘well building standard (english version). however, if we confine ourselves to strict compliance with the standards, since people do not meet any average, there are still many gaps. for example, in french standards (en 12464-1 supplemented by nf x35-103), the only indications are that the age of people must be taken into account to define the lighting levels of work surfaces. in collective housing, article 10 of the order of 24 december 2015 imposes minimum characteristics to ensure average horizontal illuminance values measured at the floor along a usual circulation route, taking into account transition zones. it goes without saying that strict compliance with these standards does not guarantee the success of an architectural project in the perception of these users (mudri, 2002). 1.3 colours and lights: factors of identity and orientation. in the literature of cognitive science and psychology, there is little research on the role of colour in its relationship to space and in particular in the spatial orientation of people. however, we know that a visual environment adapted to the pathologies of people with disabilities has positive effects, but must respect a certain number of criteria such as a certain amount of light, contrasts and an appropriate spatial distribution (damelincourt et al., 2010). we have therefore hypothesised that colour and lighting devices in the architectural environment of collective housing could help with spatial orientation, particularly for disoriented people who are less receptive to conventional signage systems (bay and fayolle, 2020). in doing so, this empirical approach will hopefully lead to a reflection on colour in collective housing environments. inherited from hygienic and standardised norms, we note, even today, that few works integrating colour are the object of a voluntary approach. the choice of colours and materials often depends on the tastes of the project manager and the usual validation of the client, but what seems to be a secondary issue is in reality a key point in the evaluation of the success of an architectural project. the results of this study will allow the development of a creative protocol that will help the developer to design visual environments that are adapted to the needs of all inhabitants. the main results expected from this study are: 1. to improve the analysis and interpretation protocol for defining comfortable visual environments. 2. to develop tools to simulate the lighting environment in the design phase of the programme. 3. facilitate the integration of the results of this study by professionals. 2. materials and methods 2.1 color-matter, color-light the protocol presented is based on a combination of chromatic expertise (chromatic countertype) concerning the choice of materials, textures and finishes, favouring colour for its plastic character; and lighting (light colours, light and well-being: characterize-ation of chromatic phenomena in collective housing 9 color culture and science journal vol. 14 (2) doi: 10.23738/ccsj.140201 characterization) concerning the quantity and colour character of light, with particular emphasis on different colour temperatures. this study focuses mainly on the creation of the common spaces and the interior horizontal circulations. indeed, the visual ambience of these spaces should create a sense of welcome, visual comfort and safety for all users, of all ages, day and night. the bidisciplinary method used will therefore serve to create coherence and harmony between the exterior landscape treatments and the interior colour and light treatments in order to create an intuitive and inclusive chain of movement. the method was divided into two stages: 2.1.1 step 1: captures the surveys presented were carried out on 26 june 2019 in capbreton (landes, france) over a period of 8 consecutive hours on the site of the future "bonamour" residence built by the property developer sobrim (sobrim haranam). the first phase consisted of collecting photographs of the site. the inventory of the existing site is an essential phase before any project. equipped with a camera (canon eos 2000d, adobe rvb colour space), this preliminary chromatic analysis was accompanied by a walk on the site which aimed at establishing a diagnosis of the architectural and vegetal environment surrounding the project in order to transcribe the essential elements. photographs cannot faithfully reproduce the colours of a palette. however, they are essential graphic documents for memorising, visualising and disseminating information (lenclos and lenclos, 2016). most chromatic studies employ photographic investigations to support colour surveys. in our case, photography was used in two approaches, one aimed at establishing an inventory of surrounding urban colours and forms, the other a colour and light diagnosis in order to judge the appearance of the site under cyclical conditions. this step was a way to transcribe and analyse the experience of a space. the second phase consisted of referencing the colours of the site with the help of countertypes. in our study, the colour survey consisted of observing the colours that make up the environment and the architectural elements surrounding the project in order to compare them to reference colour samples. here we used the colours of the ncs colour chart. the natural color system is a universal system used for standardised colour communication, based on an intuitive coding system designed for human vision. this reference system allows us to communicate colours universally in different fields of application. this representation has also allowed us to translate these colour readings into values using the cie xyz l.a.b system, taking into account the logarithmic response of the eye, but also the specific characteristics of coloured surfaces with their luminance index. the third phase consisted of a series of measurements to characterise the lighting environment of the site. this preassessment was carried out at three different times of the day (10:00, 14:00, 17:30) to measure the light amplitude. in addition, in order to analyse the distribution of light in the space, the space was divided into several areas of the site. this series of measurements was carried out with the irc cl-70f chromameter, allowing the collection of all light values. a video-luminance meter (canon eos 2000d, fish-eye 4.5mm 1:2.8 lens + photolux 3.1 software) was also used to identify areas that may be sensitive to glare and shadows caused by future buildings. 2.1.2 step 2: creation the first phase consisted in analysing the elements collected: evolution of the existing light according to the architectural and plant masks, as well as the chromatic identity of the site (see figure 1). fig. 1. environment study, capbreton, france. colours, light and well-being: characterize-ation of chromatic phenomena in collective housing 10 color culture and science journal vol. 14 (2) doi: 10.23738/ccsj.140201 each environment has a unique identity, of which colour and light are part. the mission of the colour designer must necessarily include a diagnosis of the existing environment. this stage defines the way in which we will approach the existing environment and certain elements in relation to the project, but also in relation to the promoter's wishes in terms of expected aesthetic and functional ambitions. in this phase, we have taken into account the so-called "permanent" and "cyclical" colours. the "permanent" colours are the basis of any chromatic study. they constitute the stable elements of the place, having a durable character, such as the building materials. they are opposed to "cyclical" colours, which are unstable and subject to innumerable temporal, meteorological and light variations, such as the colour of patinas, plants and the sky (etc.). the second phase consisted of recommending ambiences adapted to the site, using chromatic ranges, materials and lighting systems that favour the safety and visual comfort of all the inhabitants. this method consisted of experimentally constructing chromatic ranges by means of the view, proceeding by variation and multiplication of optical combinations until a visual impression was obtained that conformed to the aesthetic expectations of the project. to design these colour schemes, we used the ncs colours previously surveyed on site, which we then matched with the paint and plaster manufacturers' colour charts used for the project. thus, a visual and aesthetic atmosphere was conceived around the spirit of the place, the chosen shades are sublimated by the contribution of contrast around several soft and affirmed tones inspired by nature which create a coherent harmony with the vegetation present on the site. these prescriptions led to the creation of three specific colour palettes for each building in the project (see figure 2). inside, the chromatic combinations are composed of five shades, but established on a dominant trichromy , varying at each level, thus avoiding any visual disturbance caused by a discordant polychromy, and relieving the space of a certain visual monotony recurrent in this type of place. particular attention was paid to chromatic contrast and luminance values, as contrast sensitivity generally decreases with age and can be even more disturbed when visual pathology is added. thus, the luminance indices of each recommended colour are between 0.6 and 0.9 for light colours and between 0.2 and 0.45 for dark colours, and finally, a contrast of 70% has been respected between the various important media so that they can be perceived by a visually impaired person, whose sensitivity to contrasts is still operating. here, light colours are used for large surfaces and dark colours for small surfaces or accessories to allow better discrimination of spatial elements. some of the contrast values are not equal to 70%, but they have been accepted because of a negligible margin of error. the creation of these differentiated harmonies allowed us to design circulation spaces with chromatic variations for each level, favouring intuitive orientation as well as efficient and comfortable reading of the movement chain for all inhabitants. fig. 2. chromatic environment creation. these harmonies were also accompanied by a lighting project. this was studied so that the quantity and quality of light would meet the needs of all inhabitants, because the visual, light and lighting needs of people over 75 are not those of a 50 year old, and even less so of a 30 year old. due to the physiological ageing of the eye and the retina, more light is needed to perform certain daily tasks. this need is increased in the case of diseases such as glaucoma, cataract or eye damage caused by diabetes or medication. as a result, from the age of 55 onwards, the amount of light required is 300% higher than at the age of 25, and this for an equivalent level of visual performance ,(association française de l’éclairage, 2020). for this reason, we recommended an average of 300 lux on the floor throughout the chain of movement of interior spaces (entrance halls, corridors, staircases), while taking care to accentuate certain colours, light and well-being: characterize-ation of chromatic phenomena in collective housing 11 color culture and science journal vol. 14 (2) doi: 10.23738/ccsj.140201 important areas or elements by light contrast, such as the highlighting of signage elements, access to lift doors and wall decorations serving as visual and orientation markers in long corridors. this was achieved through the use of led general and ambient lighting systems that provide both direct and indirect light to accentuate the volumes while not producing harsh light-dark transitions. finally, we chose to apply a colour temperature of approximately 3000 kelvin; this choice was supported by the fact that we plotted this data on the kruithof curve (viénot, durand and mahler) in order to deduce whether the visual ambiences are considered comfortable for the majority of observers (see figure 3). fig. 3. choice of illuminance and colour temperature to create a comfortable visual environment. in addition, recent research has shown consistent effects of lighting characteristics on perceived ambience. increasing illuminance would result in a less difficult and more vivid perception of the overall ambience as would the application of warm white light (2800k) which would be perceived as more comfortable than cold white light (6000k).(kuijsters et al., 2011). also, concerning the choice of materials, we studied their lrv (light reflectance value) in order to recommend suitable finishes in all the circulation zones according to the natural light input and thus not to generate too much glare or darkness. finally, the third phase was the creation of a technical execution file for the project management. this file is based on and complements the documents provided by the project architect and includes normative descriptions as well as graphic documents such as colouring diagrams on plans, lighting system layout diagrams, cross-sections, a details and signage booklet, as well as a material library to ensure the proper implementation and monitoring of the project. 3. result the different phases of analysis helped to demonstrate how qualitatively and quantitatively the project could be perceived by the inhabitants ,(insee, 2017). mainly thanks to the exposure of the buildings, their light contributions in relation to the different masks, and the architectural and landscape aesthetics of the overall environment. the interpretation of these results allowed us to prescribe effective and coherent lumino-chromatic ambiances, taking into account the constraints linked to the respect of the local architectural aesthetics found around the site, the respect of visual contrasts as well as the hypothetical contribution of natural light entering each building. this design phase, of course, complies with current standards in the field of lighting design for this type of space, but it calls for an experimental construction method (pfeiffer, 1966), taking into account several factors intrinsic to the project: − the analysis of the colour and light characterization of the site. − the spirit and visual coherence of the project location. − an efficient chain of movement. − the comfort of use and appreciation of the spaces for all inhabitants. the outcome of this protocol was the creation of a construction file and a detail book, intended for the client in order to transcribe the information gathered into technical prescriptions, colouring principles and effective lighting of the future building (see figure 4). fig. 4. results obtained to facilitate the assimilation of space and movement. colours, light and well-being: characterize-ation of chromatic phenomena in collective housing 12 color culture and science journal vol. 14 (2) doi: 10.23738/ccsj.140201 we hypothesize that this bidisciplinary experimental expertise of chromatic and luminous characterization within its future circulation spaces will generate more visual cues and comfort of use thanks to this protocol. 4. discussion the issue of lighting and colour in collective housing is quite complex, as designers' preferences vary greatly according to both objective and quantifiable conditions (economy, standardization of practices, specific needs related to people with disabilities, etc.) and socio-cultural and subjective conditions (preference for a particular colour scheme, type of luminaire, type of covering, etc.). as a result, and in the absence of standards directly related to these semi-private spaces, architects tend to use very neutral, even monotonous, colours and materials, and struggle to install lighting that is sufficiently effective, comfortable and aesthetic in common areas. with the help of this study, we are beginning to awaken designers to the challenges of colour and light. because together, beyond their simple aesthetic contribution, they make it possible to secure and make efficient the circulations while allowing the inhabitants to plunge into singular universes where the atmosphere becomes a factor of wellbeing and cohesion. 5. conclusion in the next few years, we will repeat these measurements in the built collective residences and a comparative study will complete the research-creation protocol studied in this article. this comparative study will take into account the values obtained in the old residences and those that were built using this protocol. this study will be completed by a questionnaire intended for the inhabitants, where they will be asked to answer questions relating to their state of health, their general satisfaction with the care given to the (interior) environment of their residence and finally to describe in detail their long-term visual impression of the common spaces. they will then be asked to evaluate their visual comfort in specific places and times of the day using sensation grids. this will allow us to compare this feedback with measurements taken in situ in order to correlate the metric data collected with the visual atmosphere felt. this study will enable the property developer to ensure the efficiency of its approaches and to continue to systematically and sustainably design visual environments better adapted to human physiological needs by proving the validity of qualitative approaches in terms of the design of light and colour within its property programmes. 6. declaration of funding sources this research did not receive any specific grant from funding agencies in the public, commercial, or non-forprofit sectors. 7. declaration of conflict of interest the author has declared that no competing interests exist. 8. acknowledgement i thank the laplace laboratory of the paul sabatier university in toulouse, france for making the experiment possible by providing tools. i also thank the company sobrim for allowing me to carry out this study and for the interest shown in these results. finally, i would like to thank them for their willingness to promote and develop their university research within their future real estate programmes thanks to the haranam approach. 9. biography of the authors lorrain caumon is a cifre doctoral student in the laplace and lara-seppia laboratory of the university of toulouse (france). since 2019, she holds a master's degree in creation, research and innovation in colour (iscid, france) and is currently a colour designer specialising in inclusive space design within the company sobrim. her research focuses on the interaction between colour design and lighting sciences, with the aim of promoting comfort and well-being in collective housing. estelle guerry is a doctor of the universities of toulouse (france). she specialises in colour design and lighting science, with the aim of promoting the comfort of the elderly. georges zissis, phd, is a full professor and director of “light & matter” research group of laplace (toulouse 3 university, france). his primary area of work is in the field of light sources science and technology. céline caumon, phd and prof. at the university of toulouse-jean jaurès. with the initiative of the creation of the institute color image design (iscid, france), she participates in the development of colordesign in other scientific disciplines and in the socioeconomic world. elodie bécheras, associate professor, director of the institut couleur image design (iscid, france) and freelance scenographer. her creative and research work focuses on creative practices related to light, from the point of view of colour, city, landscape and scenography. colours, light and well-being: characterize-ation of chromatic phenomena in collective housing 13 color culture and science journal vol. 14 (2) doi: 10.23738/ccsj.140201 christelle infantes, dplg architect and head of the haranam research and development department, within the company sobrim from 2017 to 2021. licensing terms articles published in the “cultura e scienza del colore color culture and science" journal are open access articles, distributed under the terms and conditions of the creative commons attribution license (cc by). you are free to share (copy and redistribute the material in any medium or format) and adapt (remix, transform, and build upon the material for any purpose, even commercially, under the following terms: you must give appropriate credit to authors, provide a link to the license, and indicate if changes were made. you may do so in any reasonable manner, but not in any way that suggests the licensor endorses you or your use, you may not apply legal terms or technological measures that legally restrict others from doing anything the license permits. the authors keep the rights to further publish their contents where they want and can archive pre-print and postprint (submitted version and accepted version) and the published version of the pdf of their article with no embargo period. references association française de l’éclairage (2020) fiches pratiques : éclairage dans les collectivités. association française de l’éclairage, p. 56. available at: http://www.afe-eclairage.fr/. bay, b. and fayolle, c. (eds) (2020) couleur et soin. couleur et soin, paris: les presses du réel. brutel, c. (2002) ‘la population de la france métropolitaine en 2050 : un vieillissement inéluctable.’, (n° 355-356), p. 16. damelincourt, j.-j. et al. (2010) éclairage d’intérieur et ambiances visuelles. paris: éd. tec & doc (optique et vision). eideliman, j.-s. and gojard, s. (2008) ‘la vie à domicile des personnes handicapées ou dépendantes : du besoin d’aide aux arrangements pratiques’, retraite et societe, 53, pp. 89–111. insee (2017) les conditions de logement en france. available at: https://www.insee.fr/fr/statistiques/2586040?sommaire=2586377. intergovernmental science-policy platform on biodiversity and ecosystem services (ipbes) (2020) workshop report on biodiversity and pandemics of the intergovernmental platform on biodiversity and ecosystem services (ipbes). zenodo. doi: 10.5281/zenodo.4147317. kuijsters, a. et al. (2011) ‘improving the mood of elderly with coloured lighting’, in. ieee photonics technology letters ieee photonic technol lett. doi: 10.1007/978-3-642-31479-7_10. lenclos, j.-p. and lenclos, d. (2016) couleurs de la france: géographie de la couleur. le moniteur. mormiche, p. (2001) ‘l’enquête hid de l’insee’, gerontologie et societe, 2499(4), pp. 57–77. mudri, l. (2002) ‘luminous ambience, quantitative/qualitative data and subjective response’, p. 12. onu (2020) ‘note de synthèse : inclusion du handicap dans la riposte à la covid-19’. available at: https://www.un.org/sites/un2.un.org/files/covid19_inclusion_du_handicap.pdf. pfeiffer, h. (1966) l’harmonie des couleurs. cours théorique et pratique. 3ème édition. paris: dunod. piccoli, m. et al. (2020) ‘[ethical approach to the issue of confinement of the elderly in the context of the covid-19 pandemic: prevention of frailty versus risk of vulnerability]’, ethics, medicine, and public health, 14, p. 100539. doi: 10.1016/j.jemep.2020.100539. sobrim haranam (no date) le pôle recherche et développement sobrim, https://sobrim-immobilier.com/. available at: https://sobrimimmobilier.com/haranam/pole-recherche-et-developpement/ (accessed: 18 january 2022). viénot, f., durand, m.-l. and mahler, e. (no date) ‘the effect of led lighting on performance, appearance and sensations’, p. 8. ‘well building standard (english version)’ (no date) confort, santé, bien-être par l’immobilier. available at: http://www.wellsimi2015.paris/well-building-standard-english-version/ (accessed: 12 july 2022). 21 colour culture and science journal vol. 12 (2) doi: 10.23738/ccsj.120203 graphical interpolation of munsell data pietro paglierani1, simone liberini2, alessandro rizzi2, francesca valan1 1 francesca valan studio, milan, italy. pietro.paglierani@gmail.com, francesca@francescavalan.it 2 dept. of informatics, university of milan, italy. simone.liberini@unimi.it, alessandro.rizzi@unimi.it corresponding author: pietro paglierani (pietro.paglierani@gmail.com) abstract this paper analyzes the problem of converting munsell color notations (hue, value and chroma) into cie 1931 yxy coordinates using the graphical method outlined in 1943 by the optical society of america (osa). various software programs can now perform this task, running on computers or color control instruments. nonetheless, the osa graphical technique remains the reference procedure to transform munsell notations into cie coordinates. the astm “standard practice for specifying color by the munsell system” provides the data and charts needed to perform such conversion. accordingly, munsell value can be easily transformed into cie luminance y through a search in a data table. however, a guided procedure to graphically convert hue and chroma into cie chromaticity coordinates is not available yet. to fill this gap, this paper proposes a graphical technique, which can use simple drawing computer programs such as powerpoint, or more sophisticated tools for computer aided design or graphic design, such as solidwork or adobe illustrator. as an example, the proposed procedure is applied to a set of munsell color chips from the munsell book of colors, with nominal munsell notations, but unknown cie coordinates. the cie yxy coordinates of the analyzed chips are then digitally obtained by two ad hoc software conversion programs, and by instrumental measurements performed with a commercial spectrophotometer. finally, a detailed comparison of the graphically and digitally interpolated data and of the instrumental measurements is provided and discussed. keywords munsell color system, cie coordinates, visual interpolation, color measurement received 06/01/2020; revised 09/04/2020; accepted 11/05/2020 graphical interpolation of munsell data 22 colour culture and science journal vol. 12 (2) doi: 10.23738/ccsj.120202 1. introduction it is a truth universally acknowledged that specifying, matching or communicating colors in an objective way is a difficult task, even for expert practitioners endowed with sophisticated equipment. on the other hand, this unpleasant aspect of colorimetry can shed some light on the long-lasting interest of industry, academia and standard bodies for the munsell color system (mcs) and its companion, the munsell book of colors (mbc) (cochrane 2014). the mcs was proposed by albert munsell in 1905, with the aim of defining a perceptually uniform color space (newhall 1940) (newhall et al. 1943). based on a huge number of visual judgments by human observers, the mcs characterizes colors by three independent parameters hue, value and chroma, representing tint (e.g. red, yellow, or green), lightness, and difference from neutral grey, respectively (astm standard d 1535-14 2014). the mbc, conversely, consists of a collection of uniformly distributed reference colors, printed on removable paper chips. released in 1915 and commercialized in 1929, the mbc was finally updated after 1943 (cochrane 2014), based on the studies of an ad hoc subcommittee of the optical society of america (osa). the final osa results, published at first in (newhall et al. 1943), are now included in the international standard (astm standard d 1535-14 2014). the mbc chips originate a regular tridimensional grid in the munsell color space (newhall et al. 1943). they span 40 hues at constant steps of 2.5, integer values from 1 to 9, and even chroma from 2 towards the mac adam limit, i.e. the maximum chroma theoretically achievable by any object color of given hue and value (wyszecki and stiles 2000). using the mbc, one can obtain the munsell specification of an object color: to this end, (astm standard d 1535-14 2014) recommends selecting (by direct visual comparison) the perceptually closest mbc chips and linearly interpolating their munsell notations. for various reasons (some of which will be briefly discussed in the following), the mcs and the mbc are still adopted today in many color application fields, such as fashion and design, soil analysis, food control, forensic pathology, color education, and many others (cochrane 2014). the practical use of the mcs, however, very often brings about the consequent need to convert the munsell notations into cie 1931, cielab, or rgb coordinates (wyszecki and stiles 2000), in particular when the obtained color data require further processing (paglierani and valan 2018). in the literature, the problem of transforming cie 1931 coordinates into munsell notations has received greater attention than the opposite conversion, from mcs to cie – see, for instance, (rheinboldt and menard 1960), (simon and frost 1987), (smith et al. 1990), (mahyar et al. 2008). from the 60’s up to nowadays, in fact, most of the efforts in this field have aimed at converting by digital means instrumental colorimetric data (i.e. the cie coordinates evaluated by suitably processing measured reflectance spectra) into munsell notations – which should indeed be the result of a perceptual judgment by a human observer (newhall 1940), (wyszecki and stiles 2000). as a result, low cost, portable measuring devices with user-friendly interfaces are now available on the market, which can provide not only cie or cielab data, but are also capable to digitally provide perceptual munsell notations from instrumental spectrophotometric measurements – see, for instance (konica minolta 2014). digital techniques and color-control instrumentation can be extremely useful when a large amount of colors must be characterized (centore 2011). on the other hand, their practical use can be problematic in certain color control applications, specifically when the specimen under test is liquid or semi-liquid (e.g. beers, icecream or sauces in food control), non-compact (such as sand, in soil analysis, or hair, in hair dyeing control), or visually complex (e.g. diamonds or other gems) (munsell color 2020). in these cases, the use of the mbc chips still prevails, owing to their practical effectiveness and easy applicability. furthermore, various industrial or commercial recommendations issued by national or international standard bodies still adopt the mcs and ad hoc versions of the mbc to specify colors; two interesting examples are the brazilian system for soil classification (de souza 2020) or the united states standards for grades of frozen french-fried potatoes, (munsell color 2020). thus, either for the reasons summarized above or just because they prefer relying on the human color vision rather than on electronic devices, many color professionals still use the mcs and the mbc in their work. to support such practitioners, this paper will focus on the munsell to cie conversion problem. thus, for the sake of brevity, cie to munsell conversion techniques will not be considered in the following. (newhall et al. 1943) gave a fundamental contribution to the munsell to cie conversion problem, by providing the munsell renotation data (mrd) i.e a collection of reference munsell notations with the corresponding cie yxy coordinates, and outlining a graphical conversion graphical interpolation of munsell data 23 colour culture and science journal vol. 12 (2) doi: 10.23738/ccsj.120202 procedure based on specific mrd charts available in (astm standard d 1535-14 2014). one relevant limitation of the mrd (and, consequently, of the mrd charts) is the fact that the provided reference colors are only expressed as munsell notations and cie 1931 yxy specifications; hence, the mrd charts are available only in the cie xy chromaticity plane (newhall et al. 1943). as a consequence, their application can be extended to other color spaces only by means of a successive transformation, from cie to the target color space. for instance, once a munsell notation has been graphically turned to cie coordinates using the mrd charts, the corresponding cielab data can only be evaluated by applying sequentially the well-known algebraic expressions for the cie to cielab conversion (wyszecki and stiles 2000). a direct transformation between the mcs and the cielab color spaces by means of digital techniques has been analyzed in (mahyar et al. 2008), where the conversion from cielab coordinates to munsell hue is investigated. conversely, graphical techniques between cielab (or any other color space) and mcs are not known to the authors. the higher uniformity of the more recent cielab space (or of other color spaces) with respect to the cie 1931 color system system could be exploited to improve the accuracy of the conversion process (wyszecki and stiles 2000). in fact, as will be highlighted in the following, the low uniformity exhibited by the cie 1931 xy chromaticity plane is a critical aspect in the osa graphical conversion. nonetheless, this paper will focus only on the use of the mrd charts for the munsell to cie 1931 conversion procedure. the analysis of the impact of the low uniformity of the cie 1931 color space on the conversion process, and its extension to other color spaces, can represent further steps of the research activity presented in this paper. another drawback of the osa graphical procedure is that it can be quite complex and time consuming. for this reason, various software programs have been proposed, which can perform the munsell to cie conversion (babelcolor 2018), (centore 2011), (paglierani and valan 2018, conference paper). such programs are usually based on linear, linear and radial (centore 2011), or spline interpolation techniques (paglierani and valan 2018, conference paper). neural network conversion techniques have also been investigated (kang et al 2009) (tominaga 1993). to the best of the authors’ knowledge, however, these techniques are not used in practical applications yet. a partial comparison of the results provided by linear, linear and radial, or spline interpolation techniques is given in (paglierani and valan 2018, conference paper), where the lack of a suitable set of reference colors outside the mrd was highlighted as a major problem in performance analysis activities. this paper aims to contribute to this topic, by providing common guidelines and a simplified procedure to obtain reference mcs and cie 1931 data outside the mrd. in fact, as clearly stated in (astm standard d 1535-14 2014), the graphical approach is the reference conversion technique that should be used to determine the accuracy of any computer program performing the munsell-to-cie conversion. in the munsell to cie conversion, the munsell value can be simply transformed into cie luminance through a search in a data table (astm standard d 1535-14 2014). on the contrary, graphically transforming munsell hue and chroma into the cie chromaticity coordinates xy can be more complex (centore 2011). moreover, a detailed guided procedure to systematically perform such task, to the best of the authors’ knowledge, is not available yet. to fill this gap, this paper proposes a graphical munsell to cie conversion technique based on the mrd charts and supported by simple and popular computer programs for drawing, e.g. powerpoint (microsoft powerpoint 2020) or libreofficedraw (libreoffice draw 2020), or by more complex computer aided design or graphical design applications, such as solid work (solidwork 2020) or adobe illustrator (adobe illustrator 2020). the paper demonstrates the use of such tools in the munsell to cie conversion through practical examples, and verifies its reproducibility by comparing the results achieved by independent operators using different tools. the proposed procedure is then applied to a set of munsell color chips included in the mbc hence, with nominal munsell notations, but of unknown cie coordinates (intermediate mbc chips). in the paper, the cie yxy coordinates of the intermediate mbc chips are also obtained by two computer programs, i.e. (centore 2011) and (paglierani and valan 2018, conference paper). moreover, they are directly evaluated from instrumental spectrophotometric measurements obtained with a commercial instrument (konica minolta 2014), (wyszecki and stiles 2000). finally, the cie coordinates obtained by graphical or digital conversion of munsell notations and the ones directly evaluated from spectrophotometric measurements are thoroughly compared and discussed. graphical interpolation of munsell data 24 colour culture and science journal vol. 12 (2) doi: 10.23738/ccsj.120202 the procedure presented in this paper can be used by researchers who need to validate a novel digital conversion algorithm, or compare the accuracy performance of different conversion techniques. the proposed procedure can also provide a systematic way for independent researchers to produce reference color data. furthermore, this paper can be considered a tutorial for all those color practitioners who wish to acquire a deeper understanding about mcs and mbc. the structure of the paper is as follows. the next section briefly introduces the mcs, the mbc and the mrd. section 3 presents and discusses the proposed graphical conversion procedure, and the experimental use of different digital tools. section 4 summarizes the conversion algorithms proposed in (centore 2011), (paglierani and valan 2018, conference paper). finally, the graphical conversion results, the digital conversion results and the obtained measurements are described, compared and discussed. 2. the munsell color system the mcs associates colors to points in a tridimensional space, so that equal perceptual differences between colors imply equal euclidean distances between the corresponding points (astm standard d 1535-14 2014) (newhall et al. 1943). in mcs the color attributes, hue value and chroma, are represented by cylindrical coordinates: hue is the angle about the neutral axis, value is to the distance from the plane containing the black point, and chroma is the radial distance from the neutral axis. fig. 1. designation systems for munsell hue, from (astm standard d 1535-14 2014). a munsell notation is a combination of letters and numbers, written in the form phv/c, which defines the color of an opaque object with respect to the munsell hue ph, the munsell value v, and munsell chroma c. in this notation, p is a real number in (0,10] and h a letter in {r,yr,y,gy,g,bg,b,pb,p,rp} (astm standard d 1535-14 2014). the value v is a real number in [0,10]; 0 corresponds to ideal black and 10 to ideal white. the chroma c is real and non-negative. examples of munsell notations are 8.75g3.8/2 or 6pb3/5.5. in some cases, it may be convenient to use the all-number notation (see fig. 1), in which the hue is a real number in (0,100] or in (0,10] (the munsell and kubelka-munk toolbox 2019). the mrd are a collection of 2734 munsell specifications, whose corresponding cie yxy coordinates (relative to illuminant c) are given in (astm standard d 1535-14 2014) and (newhall et al. 1943); they are available in digital format at (munsell renotation data 2019). fig.2 shows the subset of mrd points with munsell value equal to 5, on the cie xy plane: one can see the manually drawn curves representing the constant-chroma and constant-hue loci of the mrd (newhall et al. 1943). the mrd points lie at the intersections between ovoids and radial curves. as an example, the red arc in fig.2 is the constant-chroma arc between the mrd notations 7.5r 5/12 and 10r 5/12. the mrd and the mrd charts are the basic elements for the munsell conversion procedures, be they graphical or purely digital. however, before analyzing the different types of procedures, we first need to define the munsell to cie conversion problem. fig 2 munsell renotation data with munsell value 5 from (astm standard d 1535-14 2014). in red the constant chroma arc between 7.5r 5/12 and 10r 5/12. graphical interpolation of munsell data 25 colour culture and science journal vol. 12 (2) doi: 10.23738/ccsj.120202 3. the munsell to cie conversion problem the munsell to cie conversion problem can be stated as follows: given a munsell notation with hue ph, value v and chroma c, find the corresponding cie yxy coordinates (centore 2011): 𝑌𝑌 = 𝑓𝑓1(𝑝𝑝𝑝𝑝, 𝑉𝑉, 𝐶𝐶) 𝑥𝑥 = 𝑓𝑓2(𝑝𝑝𝑝𝑝, 𝑉𝑉, 𝐶𝐶) (1) 𝑦𝑦 = 𝑓𝑓3(𝑝𝑝𝑝𝑝, 𝑉𝑉, 𝐶𝐶). if the munsell notation belongs to the mrd, the conversion can be easily carried out by an exhaustive search in the mrd database. conversely, for a generic munsell notation outside the mrd, it is necessary to rely on (1) to find the corresponding cie coordinates. the luminous reflectance factor y depends only on the value v; hence, one can write y = f1(v). a conversion table to directly obtain y from v is available in (astm standard d 1535-14 2014). unfortunately, useful approximations of the functions f2 and f3 in (1) are not available (centore 2011). thus, there are two possible ways to convert hue and chroma to the cie xy parameters. one approach is the graphical procedure outlined in (newhall et al. 1943) and recommended by (astm standard d 1535-14 2014). the second one consists in a tri-dimensional search and interpolation process based on the mrd, digitally implemented by a computer program (centore 2011). when converting a generic munsell notation, any available procedure (be it graphical or software-based) necessarily starts by transforming the closest adjacent munsell notations having multiple-of-two chroma and integer value: for a detailed discussion of this aspect, see (astm standard d 1535-14 2014), (centore 2011), (paglierani and valan 2018, conference paper). once such adjacent munsell notations have been converted, their cie coordinates can be easily interpolated, so as to obtain the coordinates of the generic munsell notation to convert (astm standard d 1535-14 2014). as a consequence, in the following, we will only consider (without loss of generality) the conversion of munsell notations lying on the constant-chroma ovoids (at multipleof-two chroma) drawn in the integer-value planes shown in the mrd charts (centore 2011). 3.1 the graphic conversion procedure the first step in the graphic conversion procedure consists in determining the chart (identified by an integer value from 1 to 9) and the ovoid in that chart (determined by a multiple of two chroma) on which the munsell notation to convert lies. then, one must find the arc containing such munsell specification, delimited by the two closest mrd notations (centore 2011). as an example, we will consider the problem of determining the cie coordinates of the munsell notation 8.75r5/12, which is an intermediate color sample physically available in some editions of the mbc. the mrd notations closest to 8.75r5/12 and with the same value and chroma are 7.5r5/12 and 10r5/12, as one can see in the zoomed chart (value 5) shown in fig.3. fig 3. munsell notation to convert (8.75r 5/12) and the two closest mrd notations with the same value and chroma. fig 4. graphical interpolation of the munsell specification 8.75r5/12 obtained with powerpoint. graphical interpolation of munsell data 26 colour culture and science journal vol. 12 (2) doi: 10.23738/ccsj.120202 once the position of 8.75r5/12 on the arc between 7.5r5/12 and 10r5/12 is known, its xy coordinates can be straightforwardly obtained on a paper print of the chart, or digitally on a personal computer, e.g. using a drawing program such as powerpoint. the searched xy values are the coordinates of the point corresponding to 8.75r5/12, read on the x and y axis of the chart. however, determining the accurate position of such a point on the arc is less trivial. to overcome this difficulty, we need to assume a linear relationship between arc lengths in the cie xy plane and numeric hues. from an operating point of view, this assumption is fundamental to locate the color position in the cie xy plane, and proceed with the interpolation process. on the other hand, the non uniformity of the cie xy plane is wellknown (wyszecki and stiles 2000); hence, assuming a linear relationship between hue and arc length in the cie xy plane could give rise to observable non-linear effects, if a statistical analysis of the converted data were performed. nonetheless, this type of statistical analysis is out of the scope of this paper. thus, in the following, we will accept the linearity assumption discussed above as a necessary working hypothesis, and postpone this type of investigation (together with its extension to more recent, approximately uniform color spaces such as cielab) to the next steps of this research work. fig. 5. graphical interpolation of the munsell specification 8.75r5/12 obtained with adobe illustrator. fig. 6. graphical interpolation of the munsell specification 8.75r5/12 obtained with solidwork in the considered conversion example, the hue of 8.75r5/12 is exactly intermediate between 7.5r and 10r; hence, the searched point on the chart divides in two equal parts the arc between 7.5r and 10r. in general, if hx is the hue of the munsell notation to convert, h1 and h2 the hues (h2 > h1) of the adjacent mrd notations, and l the length of the arc between h1 and h2, the semi-arc length lx from h1 to hx can be evaluated as: 𝐿𝐿𝑥𝑥 = 𝐻𝐻𝐻𝐻−𝐻𝐻1 𝐻𝐻2−𝐻𝐻1 l. (2) to evaluate (2), the length l of the entire arc from h1 to h2 is needed. such a value can be obtained by approximating the arc as a sequence of linear segments of fixed length lu. fig.4 shows an example of arc approximation with a sequence of juxtaposed linear segments (in red and blue) of constant length lu, superimposed to the arc in the mrd chart. in this case, the length l was obtained with power point. notice that the final segment (in green) has a shorter length than lu, to adjust the sequence of approximating segments to the arc. the length lx of the semi-arc can be obtained in the same way. to verify the reproducibility of the proposed graphical approach, a second operator independently (i.e. without any information coming from the previous powerpointbased conversion experiment) transformed the munsell notation 8.75r 5/12 to cie coordinates using the adobe graphic design tool illustrator. the output of the procedure is summarized in fig. 5. finally, a third operator independently performed the same conversion, using a computer aided design tool, i.e. solidwork. in this case, the lengths l and lx were obtained by approximating the arc as a circle, by means of the built-in functionalities provided by solidwork. the graphical interpolation of munsell data 27 colour culture and science journal vol. 12 (2) doi: 10.23738/ccsj.120202 circular curve interpolating the arc and the obtained results are shown in fig.6. as one can easily verify, even if performed with different tools and carried out by different independent operators, the results of the three conversions are very close. 3.2 liner/radial digital interpolation the mkt algorithm extends the purely linear interpolation technique suggested in (rheinboldt and menard 1960) by using radial interpolation where the mrd constant-chroma ovoids exhibit a higher curvature (centore 2011). the mkt is open source, available in python (colour science for python 2019) or matlab (the munsell and kubelka-munk toolbox 2019). its details are thoroughly described and discussed in (centore 2011). the algorithm mimics the graphical procedure described in the previous paragraph by digital means, using the two mrd samples, p1h1v/c and p2h2v/c, adjacent to phxv/c, and their coordinates (x1,y1) and (x2,y2). to decide if linear or radial interpolation should be applied, a lookup table is used (centore 2011). if linear interpolation applies, the algorithm transforms the hues into real number in the range (0,10]. the searched coordinates are calculated as: (𝑥𝑥, 𝑦𝑦) = 𝐻𝐻2−𝐻𝐻𝐻𝐻 𝐻𝐻2−𝐻𝐻1 (𝑥𝑥1, 𝑦𝑦1) + 𝐻𝐻𝐻𝐻−𝐻𝐻1 𝐻𝐻2−𝐻𝐻1 (𝑥𝑥2, 𝑦𝑦2) for radial interpolation, the xy coordinates (x1,y1) and (x2,y2) of p1h1v/c and p2h2v/c must be first transformed into polar coordinates (θ1,ρ1) and (θ2,ρ2), with respect to the illuminant c neutral point. moreover, mkt transforms hues in temporary hue angles, th. the polar coordinates of phxv/c are finally obtained as: (𝜃𝜃, 𝜌𝜌) = 𝑇𝑇𝐻𝐻2−𝑇𝑇𝐻𝐻𝐻𝐻 𝑇𝑇𝐻𝐻2−𝑇𝑇𝐻𝐻1 (𝜃𝜃1, 𝜌𝜌1) + 𝑇𝑇𝐻𝐻𝐻𝐻−𝑇𝑇𝐻𝐻1 𝑇𝑇𝐻𝐻2−𝑇𝑇𝐻𝐻1 (𝜃𝜃2, 𝜌𝜌2) and then transformed in xy coordinates. 3.3 spline interpolation the spline interpolation technique is described in (paglierani and valan 2018, conference paper). while the mkt algorithm uses only the adjacent points to interpolate a notation, the spline technique can use all the points belonging to a constant chroma ovoid (or even to constanthue radial lines). the basic idea behind this algorithm is to express any mrd chart ovoid, identified by constant integer value v and multiple-of-two chroma c, by approximate mathematical formulas, which can be expressed in parametric form as: 𝑥𝑥 = 𝑔𝑔1(𝑝𝑝), 𝑦𝑦 = 𝑔𝑔2(𝑝𝑝) (3) to evaluate the xy coordinates, we substitute in (3) the unknown functions 𝑔𝑔1, 𝑔𝑔2 with their approximations 𝑔𝑔1and 𝑔𝑔2, obtained by applying spline interpolation to the subset of mrd points lying on the found ovoid (press et al. 2007). to this end, one must collect the xy coordinates (xi,yi) and numeric munsell hues hi of the mrd points lying on the identified ovoid in the vectors x=[x1,…xn]t, y=[y1,…yn], and h=[h1,…hn]. the desired xy coordinates are: 𝑥𝑥 = 𝑔𝑔1(𝑝𝑝), 𝑦𝑦 = 𝑔𝑔2(𝑝𝑝) where: 𝑔𝑔1 = 𝑠𝑠𝑝𝑝𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠(𝑝𝑝, 𝑥𝑥), 𝑔𝑔2 = 𝑠𝑠𝑝𝑝𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠(𝑝𝑝, 𝑦𝑦), while: 𝑞𝑞 = 𝑠𝑠𝑝𝑝𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠(𝑡𝑡, 𝑧𝑧) represents the cubic spline interpolant polynomial q of the data values z, at data sites t (press et al. 2007). since the ovoids are closed curves, it is necessary to extend and wrap the vectors x, y and h, repeating the initial and final values (paglierani and valan 2018 conference paper). the interpolation procedure is finally performed by (6)-(7), with the extended vectors x’, y’ and h’ taking the place of x, y and h. 4 numerical and experimental results to analyze the performance of the considered graphical and digital interpolation techniques, a set of intermediate mbc color chips were used. such sequence of munsell specifications is reported in the first column of table i; for the sake of simplicity, they all have value equal to 5 and chroma equal to 12. for each munsell specification, the corresponding cie xy coordinates were obtained by applying the graphical procedure described in section 3.1, using powerpoint. the results are shown in the second column of table i, while the third and fourth columns report the corresponding digitally interpolated values provided by the mkt and the spline algorithms, respectively. finally, the fifth column contains the results of the measurements performed on the physical chips of the mbc, obtained by using the konica-minolta spectrophotometer cm-2600d (konica minolta 2014). preliminary tests showed a high repeatability of the cie coordinate measurements. for this reason, the measurement process was repeated four times for each physical chip; the fifth column in table i shows the average measured coordinates. the standard deviations obtained from all the performed measurements resulted very similar for the x and y coordinates, close to σx = σy = σ = 0.0001. as an example, the cie coordinates obtained by the graphical procedure and the averaged coordinates graphical interpolation of munsell data 28 colour culture and science journal vol. 12 (2) doi: 10.23738/ccsj.120202 provided by the konica minolta instrument are shown in fig.4, in light blue and red, respectively. from tab. 1, it was possible to evaluate the geometric distance between the cie coordinates provided by the different approaches. the final results are reported in tab. 2. as one can immediately notice, the maximum geometric distance occurs between graphical interpolation data and instrumental measurements. conversely, the data obtained by the two digital algorithms achieve the minimum distance. finally, one can observe that, quite surprisingly, the digital interpolation techniques, though based on the mrd, provide data closer to the spectral measurements than to the graphical interpolation results. 5. conclusions this paper has presented a graphical technique, based on digital drawing tools, to perform munsell to cie data conversion. the procedure has been described through a practical example, in which a munsell notation has been transformed to cie coordinates by three independent operators using different digital tools, so as to verify its reproducibility. the procedure has also been applied to a set of color chips available in some editions of the munsell color book, whose cie coordinates are not known. moreover, instrumental measurements of the chip cie coordinates have been performed, using a konica minolta cm-2600d spectrophotometer. the obtained data have been analyzed and discussed. the interpolation results provided by the two digital interpolation techniques result quite close. the maximum geometric distance is observed between graphical interpolation data and instrumental measurements. the results of the digital algorithms are closer to the instrumental measurements than to the graphical interpolation results. the presented procedure can be used to assess the conversion performance achieved by computer programs, and to further analyze the relationship between munsell notations and cie coordinates as enforced by the munsell renotation data. further steps in this research activity can be observer tests to assess the linearity of interpolated data in terms of appearance, the main characteristics of the munsell book of colors, and investigating the possible use of other color spaces to improve the conversion process of the munsell notations. munsell spec graphical interpolation (x,y) mkt interpolation (x,y) spline interpolation (x,y) spectral measurements (x,y) 8.75r 5/12 0.5409, 0.3516 0.5384, 0.3519 0.5395, 0.3520 0.5393, 0.3537 1.25yr 5/12 0.5442, 0.3613 0.5485, 0.3784 0.5502, 0.3789 0.5467, 0.3786 3.75yr 5/12 0.5464, 0.4027 0.5455, 0.4025 0.5454, 0.4025 0.5487, 0.4021 1.25g 5/12 0.2694, 0.5421 0.2616, 0.5431 0.2650, 0.5431 0.2644, 0.5360 3.75pb 5/12 0.1875, 0.1852 0.1856, 0.1875 0.1847, 0.1874 0.1849, 0.1899 6.25pb 5/12 0.2016, 0.1837 0.2039, 0.1839 0.2029, 0.1840 0.2082, 0.1933 3.75rp 5/12 0.3829, 0.2422 0.3831, 0.2424 0.3829, 0.2424 0.3817, 0.2399 6.25rp 5/12 0.4166, 0.2600 0.4172, 0.2602 0.4163, 0.2599 0.4202, 0.2607 tab. 1. simulation and experimental data graphical interpolation of munsell data 29 colour culture and science journal vol. 12 (2) doi: 10.23738/ccsj.120202 graphical interpolation mkt interpolation spline interpolation spectral measurements graphical interpolation x 0.0070 0.0069 0.0084 mkt interpolation 0.0070 x 0.0015 0.0051 spline interpolation 0.0069 0.0015 x 0.0053 spectral measurements 0.0084 0.0051 0.0053 x tab. 2. interpolation technique comparison via geometric distance 6. conflict of interest declaration the authors certify that they have no affiliations with or involvement in any organization or entity with any financial or non-financial interest in the subject matter or materials discussed in this manuscript. this research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors 7. funding source declaration this research did not receive any specific grant from funding agencies in the public, commercial, or not-forprofit sectors. 8. acknowledgment the authors are grateful to mr. roberto pellanda of konica minolta, for the constant and effective support provided during the munsell color chip measurement sessions. 9. short biography of the authors pietro paglierani • received the master degree and ph.d. degree in electronic engineering from the university of padua. he is currently a signal processing scientist at the nato center for maritime research and experimentation (cmre) in la spezia, italy. his main research interests are in digital signal processing, underwater acoustic communications, color processing. he was previously with italtel s.p.a, tektronix padova, necsy s.p.a. and consorzio padova ricerche, where he was involved in the design of signal processing applications. simone liberini • received his ms degree in biomedical engineering at polytechnic university of milan. he worked as a research fellow at ibfm, milan, where he contributed to an image-based frame of assessment of parotid glands shrinkage in head-and-neck cancer patients. he is currently external researcher at university of milan, where he is involved in quantitative and perceptual analysis of applications of the munsell colour system alessandro rizzi • is full professor at the department of computer science at the university of milan, teaching multimedia and colorimetry. he is doing research since 1990 in the field of digital imaging with a particular interest on color, visualization, photography, hdr, vr and on the perceptual issues related to digital imaging, interfaces and lighting. he is the head of the mips lab at the department of computer science. he has been one of the founders of the italian color group, secretary of cie division 8, is&t fellow and vice president. in 2015 he received the davies medal from the royal photographic society. he is co-chair of the is&t conference “color imaging: displaying, processing, hardcopy and applications”, topical editor for “applied color science” of the journal of optical society of america, associate editor of journal of electronic imaging, member of several program committees of conferences related to color and digital imaging, and author of more than 300 scientific works. francesca valan • industrial designer, specialized in the design of colors, materials, and finishes (cmf design). she graduated in industrial design at ied in milan in 1989 and received her master in surface quality in 1990. she lives and works in milan, where she founded her studio in 1998. as an industrial designer, her activity consists in defining product identity. her cmf projects range from elevators to office furniture, from home appliances to sport graphical interpolation of munsell data 30 colour culture and science journal vol. 12 (2) doi: 10.23738/ccsj.120202 items, pens, glasses etc. she has collaborated with de longhi group, lechler, samsung, telecom italia, lg, hitachi, olivetti, atomic, technogym, fila, campari, and many others. she is a teacher in university and master courses in color design technology. she developed a method of prediction of trends based on historical and statistical analysis of color by market sector, which exploits the periodicity of color preferences and the duration of cycles for product type. references adobe illustrator. available at: https://www.adobe.com/it/products/illustrator.html (accessed april 2020). astm standard d 1535-14 (2014). standard practice for specifying color by the munsell system. babelcolor (2018). colour measurement and analysis. available at http://www.babelcolor.co. 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(2000). color science: concepts and methods, quantitative data and formulae. 2nd edn. hoboken: wiley. https://munsell.com/color-blog/defining-soil-profiles/ https://sensing.konicaminolta.us/products/cm-2600d-spectrophotometer/ https://sensing.konicaminolta.us/products/cm-2600d-spectrophotometer/ https://www.libreoffice.org/discover/draw/ https://www.microsoft.com/en-us/microsoft-365/powerpoint https://www.microsoft.com/en-us/microsoft-365/powerpoint https://munsell.com/color-blog/perfect-french-fries-sides/ https://www.osapublishing.org/josa/issue.cfm?volume=30&issue=12 https://doi.org/10.1364/josa.30.000617 https://www.solidworks.com/it/lp/just-cad http://www.munsellcolourscienceforpainters.com/munsellandkubelkamunktoolbox/munsellandkubelkamunktoolbox.html http://www.munsellcolourscienceforpainters.com/munsellandkubelkamunktoolbox/munsellandkubelkamunktoolbox.html 86 color culture and science journal vol. 15 (1) book review: i colori sono di tutti? 22 domande curiose sul colore marcello picollo lia luzzatto e renata pompas: i colori sono di tutti? 22 domande curiose sul colore, edizioni mediterranee, 2022. [italian language] since the early years of the last century, color, and the world surrounding it, has attracted increasing interest of professionals from various fields. scholars have explored its function and meaning, academics and color associations have organized conferences and workshops that have deepened and popularized this complex and fascinating world. the continued interest in exploring color and understanding its significance is clearly demonstrated by the number of new publications that have appeared nationally and internationally in recent years. these include the work "i colori sono di tutti? 22 domande curiose sul colore" by lia luzzatto and renata pompas (edizioni mediterranee, 2022, pp. 259), which is aimed at an audience of non-specialists with an innate desire to satisfy their curiosity and delve into a path of thinking outside the box. the book is, in fact, designed and structured in a simple and straightforward way, providing answers to basic questions, some not immediately obvious, concerning color and its meaning. the book, as the subtitle suggests, is divided into 22 chapters. it opens with a very brief but intriguing 'introduction' that unlocks the door to this colorful journey for the reader. each of the subsequent chapters addresses a well-defined topic starting with a specific question related to color and its analysis. among the many, and among the ones that most intrigued and fulfilled me personally, i would like to mention those related to such questions as 'does everyone own color?', 'is color tasty?' and 'does marketing love color?' in these chapters, the authors guide the reader, albeit in just a few pages, through a succession of information, news, curiosities and considerations of their own that make for lively and extremely enjoyable reading. the authors have an established and extensive experience in the world of color, both as writers of books and as journalists, having collaborated with prestigious magazines and weeklies, as well as teaching academic courses and seminars. in short, the newly published volume clearly reflects the authors’ mastery of a range of themes and their overall expertise in the field of color. the volume sheds light on what color is and how it may operate in society. licensing terms articles published in the “cultura e scienza del colore -color culture and science" journal are open access articles, distributed under the terms and conditions of the creative commons attribution license (cc by). you are free to share (copy and redistribute the material in any medium or format) and adapt (remix, transform, and build upon the material for any purpose, even commercially, under the following terms: you must give appropriate credit to authors, provide a link to the license, and indicate if changes were made. you may do so in any reasonable manner, but not in any way that suggests the licensor endorses you or your use, you may not apply legal terms or technological measures that legally restrict othersfrom doing anything the license permits. copyright: the authors keep the rights to further publish their contents where they want and can archive pre-print and post-print (submitted version and accepted version) and the published version of the pdf of their article with no embargo period. 50 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130206b geometric models for color perception nicoletta prencipe 1&2 , edoardo provenzi 1 1 université de bordeaux, cnrs, bordeaux inp, imb, umr 5251, f-33400, talence, france. nicoletta.prencipe@math.u-bordeaux.fr, edoardo.provenzi@math.u-bordeaux.fr 2 huawei technologies sasu, france. nicoletta.prencipe1@huawei.com corresponding author: nicoletta prencipe (nicoletta.prencipe@math.u-bordeaux.fr) abstract in 1962 and 1974, respectively h. yilmaz and h.l. resnikoff published two groundbreaking articles about color perception, which were ignored by the scientific community. yilmaz showed the striking analogy between lorentz transformations and the modification of color perception under illuminant changes. on the other hand, resnikoff, using mathematical techniques coming from theoretical physics, studied the possible geometrical representations of a homogeneous space of perceived colors, i.e. a space in which all the elements have “the same importance”. both works come up to the same conclusion: the structure of the space of perceived colors can be better characterized through hyperbolic geometry, while usual color spaces have a euclidean structure. in this work, we show how a modern revision of these important articles allows us to highlight a correlation between the colorimetric attributes and some objects of special relativity theory and quantum mechanics, opening innovative perspectives in the theoretical comprehension of perceptual phenomena related to human chromatic vision. a remarkable result of this new formalism concerns the retinal chromatic encoding expressed by the sum of an achromatic signal and two opponent chromatic signals (typically called red-green and yellow-blue). this looks as an intrinsic description of a socalled “color state”, in contrast to what happens in natural image statistics, where such an encoding is not an intrinsic result of the theory, but it is obtained through a principal component analysis. keywords yilmaz, resnikoff, jordan algebras, relativity, quantum mechanics, mathematical models for color perception. received 04/03/2021; revised 06/04/2021; accepted 26/09/2021 geometric models for color perception 51 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130206b 1. introduction the scope of this paper is to give a brief and simple overview, with dissemination purposes, about a novel program of formalization of colorimetry in which both geometry and techniques typically used in mathematical physics play a fundamental role. due to space limitations, and in order to keep the storytelling as simple as possible, we will leave many details to open access references that the interested reader may wish to consult. 2. yilmaz’s relativistic model the value of yilmaz’s work (yilmaz, 1962) lies in the interpretation of color perception as a relativistic phenomenon. indeed, as einstein showed up that space and time are relative to the single inertial observers (i.e. observers moving with constant speed with respect to each other), in the same way yilmaz states that the colors perceived by an observer adapted to a certain broadband illuminant are relative to it. thence it is possible to use the mathematical tools typical of einstein’s special relativity theory to model color perception. on one hand this opens new paths for a deeper comprehension of what is a color space and which are the most suitable coordinates to identify a perceived color, on the other hand it provides a mathematical formalization of the space’s transformations under changes of the broadband illuminant to which the observer is adapted. this last aspect makes yilmaz’s model easy to adapt for applicative purposes, in particular for color correction of digital images. 2.1. the coordinates as it is well-known from (wyszecki and stiles, 1982), there are strong physiological and psychophysical reasons behind the statement that the space of perceived colors is a 3-dimensional cone. thence every perceived color can be univocally identified by three coordinates. the wide range of color spaces proposed for digital and industrial applications clearly shows that the choice of these three parameters is far from being trivial. for yilmaz, a trichromatic observer adapted to a certain illuminant i is able to identify the colors he/she perceives by two chromatic coordinates and an achromatic one. let us fix three orthogonal axes, depicted in fig. 1. the origin of the three axes corresponds to black, denoted by k, on each axis there is the value associated to a certain coordinate. let us call these three coordinates α, β and γ. fig. 1. axes α, β, γ. the achromatic coordinate γ goes from black to white, through a grayscale, while the chromatic coordinates belong to the plane α, β (we will call it chromaticity plane) shown in fig. 2. the first chromatic coordinate is the angle ɸ, called hue, the second one is the radial coordinate ρ, called chroma. fig. 2. chromaticity plane. the axes α and β represent respectively the hue oppositions red-green and blue-yellow, proposed for the first time by hering. the existence of these two oppositions is the reason why it is impossible to perceive e.g. a reddish green or a yellowish blue. in this paper, we will follow the simplified yilmaz framework in which wellknown perceptual effects that show interdepencence between chromatic attributes are ignored. as a consequence, the space in which we will work has cylindrical shape, see fig. 3. using the coordinates α and β is mathematically equivalent to using the coordinates ɸ and ρ, but perceptually less immediate. a colorimetric attribute of fundamental importance, dependent to the ones defined above, is the saturation σ. it denotes the purity level of a color and it is defined as the ratio between chroma and the achromatic coordinate σ = ρ / γ. the existence of a maximal perceivable saturation (i.e. a maximum attainable degree of purity that a perceived color can have) leads us to the exclusion of the points of the cylinder that do not belong to the cone of slope ∑ depicted in fig. 4. geometric models for color perception 52 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130206b fig. 3. cylindrical coordinates. fig. 4. cone of perceived colors. note that, when γ=1, we have that σ = ρ. the perception of a stimulus constituted by a monochromatic light (e.g. a red laser) will have maximal purity, hence saturation ∑. 2.2. the two rooms experiments yilmaz motivates the introduction of relativistic concepts in a colorimetric framework through three experiments. it must be stressed that yilmaz did not give quantitative data nor apparatus description for his experiments, thus, a doubt about the fact that they have actually been implemented still remains. let us consider two different broadband illuminants, we will denote them by i and i'. let us call α, β, γ (α', β', γ', respectively) the coordinates that an observer adapted to i (to i' respectively) associates to the stimuli that he/she perceives. yilmaz’s aim is to show how the coordinates α, β, γ are transformed into the coordinates α', β', γ'. let us suppose we have two adjacent rooms completely painted in white. in each room, different kinds of light sources can be posed. the two rooms are separated by a wall with a tiny hole through which an observer placed in the first room is able to perceive light stimuli posed in the second room and vice-versa. hence the presence of the hole allows the observer to perceive light stimuli belonging to an environment to which he/she is not adapted. a piece of white paper is divided into two parts, each of them is posed in one of the two rooms. we are going to introduce just the two more emblematic experiments. experiment 1: the perception of white is relative in this first experiment, depicted in fig. 5, i is placed in the first room and i' in the second one. in a first phase the observer is placed in the first room and adapted to i. he/she perceives the piece of white paper placed in his/her same room as white; while the other half, placed in the second room and enlightened by i', has greenish hue and small saturation σ. the second phase of the experiment is identical, but the roles of the two rooms are inverted: the observer is placed in the second room and adapted to i'. he/she perceives the piece of white paper placed in the room with him/her as white, while the other one, posed in the first room is perceived as having reddish hue and the same small saturation σ. fig. 5. experiment 1. experiment 2: the invariance of the spectral red in the second room is placed a monochromatic red light source, while the first room is enlightened by i in a first phase and by i' in a second phase. in both phases the observer is placed in the first room and adapted to the broadband illuminant enlightening it. he/she observes that, in both cases, the piece of white paper, posed in the second room and illuminated by the red laser, is perceived as having the same red hue and the same maximal saturation ∑, see fig. 6. geometric models for color perception 53 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130206b fig. 6. experiment 2. formalizing the information given by the three experiments, the coordinate transformation (linear in the variables α, β, γ) that yilmaz obtained is the following: the details needed to understand how to arrive to this kind of transformations are available in (prencipe et al., 2020). in the same paper, the reader can find the description of the third yilmaz experiment, which is more involved to discuss and not relevant for the present paper. 2.3. parallelisms with relativity the “relativistic jump” is attained recognizing in the transformation written above a so-called lorentz boost, which allows us to find relativistic analogues for all the quantities mentioned up to now. in the theory of special relativity, the measure of space and time is relative to the observer, hence every observer has his/her own coordinate system with respect to which he/she can measure space and time. in the simplest case of inertial observers, i.e. observers moving with constant speed with respect to each other, the transformations converting the coordinates of one observer into the coordinates of another one, are the lorentz boosts. thence an observer adapted to a broadband illuminant corresponds to an inertial observer in special relativity theory. consequently, there will be parallelisms between spacetime coordinates and the coordinates of the perceptual space described in subsection 2.1. in particular, the achromatic coordinate γ corresponds to time, while the chromatic coordinates α, β (or, equivalently, ɸ and ρ) are the analogous of a two-dimensional physical space. from the definition of saturation as σ = ρ / γ, it is easy to deduce its relativistic analogue. indeed, it should be a ratio between a spatial and a temporal quantity, so a constant velocity. the maximum perceivable saturation ∑ corresponds to the maximum attainable velocity, i.e. the speed of light c. as a consequence of this, it is clear that yilmaz’s second experiment is nothing but a colorimetric reinterpretation of the fundamental principle of special relativity theory stating that light speed is the same for all inertial observers. for further details see (prencipe et al., 2020). 3. resnikoff’s model and its quantum reinterpretation as we have seen in section 1, yilmaz’s model introduces in the context of color perception analysis concepts and tools typical of special relativity theory. in this second section, we will see how resnikoff’s model allows us to see in color perception a quantum phenomenon. resnikoff’s article (resnikoff, 1974), gone almost unnoticed by the scientific community as yilmaz’s one, is an extraordinary (and rare) example of something that we could call “theoretical psychophysics”, because he used the typical flow of thinking and mathematical techniques of theoretical physics, but applying them to the concept of perceived color, i.e. a psychophysical attribute. more precisely, he started his analysis from the so-called schrödinger’s axioms (schrödinger, 1920), adding a further fundamental one: the homogeneity axiom, and determining mathematically which geometric structures satisfy all the axioms. notice that the pattern followed by resnikoff, which characterizes the works of modern theoretical physics, is substantially different from a mere procedure of selection by interpolation, that is a work of minimization of the discrepancies with the experimental data. resnikoff showed that only two geometric structures are compatible with schrödinger’s axioms and his homogeneity axiom: the first one is the canonical helmholtz-stiles space that has many different practical expressions like lms, rgb, xyz, etc. all of them geometrically equivalent; the second one is a hyperbolic structure totally new in color theory. it is exactly this last one that allows a quantum interpretation, as we will detail in the following. 3.1. the axiomatic construction of a homogeneous color space erwin schrödinger, well known for his works in quantum mechanics, dedicated many years of his scientific career to the study of color. in 1920 he wrote a series of very elegant works summarizing in a mathematically coherent framework the main results concerning color obtained by scientists like newton, grassmann, maxwell and helmholtz. geometric models for color perception 54 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130206b schrödinger’s axioms can be summarized stating that the space of perceived colors of trichromatic observes has the geometric structure of a convex regular cone of dimension 3. the fact that the space of perceived colors is a cone means that a positive multiple of a perceived color (i.e. a brighter version of the color) is still a perceived color (note that this is an idealization, because the phenomenon of saturation of the photoreceptors implies that the cone is not infinite, but truncated at the glare threshold). the convexity property means that, inside the cone, the segment joining any couple of perceived colors is made up by perceived colors (this was proved by grassmann). regularity is a technical property that can be translated into practical terms into the statement that the cone of perceived colors has a vertex corresponding to black. finally, the dimension of the cone is a consequence of the existence of 3 kinds of retinal cones which start the chain of neural events leading to color vision. resnikoff, starting from the observation that no color is “special” with respect to the others and that, thanks to the well-known phenomenon of chromatic induction, it is possible to modify the perception of any chromatic stimulus just embedding it in an appropriate background, came to the conclusion that the following postulate holds: the space of perceived colors is locally homogeneous, that is it exists an invertible transformation which maps any color to any “sufficiently similar” other color. it can be easily proven that this postulate, justified by the induction phenomenon, together with the convexity of the cone, implies its global homogeneity, which is exactly the mathematical property characterizing the spaces where no point is special because we can pass from one point to any other one through an invertible transformation. this is the reason of the choice of adjective “homogeneous”. in summary, putting together resnikoff’s axiom and schrödinger’s ones, we can conclude that the space of perceived colors has the structure of a convex regular and homogeneous cone of dimension 3. there are only two kinds of cones of dimension 3 satisfying all these properties: the first, and the simplest one, let us denote it by p', is the set of all the nonnegative real numbers cartesian to itself three times, which is exactly the helmholtz-stiles space, canonically used in colorimetry. the second one, more complex and interesting, denoted by p'', is given by the cartesian product of the set of positive real numbers and a hyperbolic space which can be characterized in many different ways, some of them are easy to visualize, like the hyperboloid embedded in the real three-dimensional space, the upper-half plane or the poincaré disk (i.e. the open unit disk in the real plane), others are more abstract, like, for example the space of the real symmetric positive-definite 2x2 matrices having determinant equal to 1 or the quotient space sl(2,r)/so(2). for more details see (provenzi, 2020). in the following subsection, we are going to show that this second space is the most interesting one from a theoretical point of view and for the consequences related to the quantum interpretation of color vision. 3.2. jordan algebras and the link with quantum mechanics in the articles (berthier and provenzi 2019; berthier, 2020) a fact of fundamental importance is stressed: the so-called classification theorem of jordan-von neumannwigner states that the two structures found by resnikoff for the space of perceived colors coincide exactly with the only two possible forms of a symmetric cone of dimension 3, where a cone is said to be symmetric if it is convex, regular, homogeneous, open and self-dual (a technical property which is not important to explicit here). moreover, koecher-vinberg theorem states that every symmetric cone is the so-called positive cone of a (formally real) jordan algebra. without going into many specialized and complicated details of the theory of jordan algebras, which will result to be merely notional, we just say that a jordan algebra is a vector space endowed with a commutative, but not associative product called the jordan product and that the jordan algebra whose positive cone is p'' is the algebra a of the real symmetric 2x2 matrices with the jordan product between two matrices a and b of a defined as: a○b=(ab+ba)/2. jordan algebras have a privileged role in the modern quantum theories, where the objects are the quantum observables of a system, in duality with their quantum states. once again, an exhaustive treatment of these concepts should deserve much more space, see e.g. (berthier and provenzi, 2021), hence we just underline that it is the lack of associativity of the jordan algebra that gives a quantum character to the description of the observables and the states of the system. to make the theoretical ideas exposed up to now more concrete, let us now talk about a feature of this quantum model for color perception that we consider particularly meaningful. it is the fact that it is possible to represent, in a very natural way, a color state through the superposition of three so-called density matrices, indicated with , (i.e. positive definite and with unit trace) which represent an achromatic state and two states of chromatic opponencies red-green and yellowblue, respectively, as expressed in the following formula: geometric models for color perception 55 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130206b this kind of description, perfectly coherent with the human color vision, as remarked in section 1, is obtained in the quantum model just passing to a parametrization in polar coordinates of the density matrices. the color encoding performed by the human visual system comes out in a very natural way in the framework of the quantum model and there is no need to resort to an analysis “a-posteriori”, like it is done in the context of natural image statistics, where it is shown that the principal components of a wide dataset of natural images coincide with the triplet given by the achromatic axis and two chromatic axes having opponent colors. 4. conclusions the power of yilmaz’s work lies in the fact that he gave the foundations to construct a relativistic theory of color perception. clearly here we exposed just some of the possible aspects of special relativity theory translated in the colorimetric context. the analogies between the two theories are much more, and they hide questions deserving further and deeper investigations in the colorimetric context. furthermore, there are numerous aspects that are well suited to immediate and concrete applications. let us imagine we have a picture taken by a digital device which is not able to automatically adapt, like a human being, to the illuminant of the scene we want to capture. we can imagine that the uncorrected image as a light stimulus posed in the second room in yilmaz’s first experiment, with an observer posed in the first room. indeed, it corresponds to a perception devoid of adaptation, that can be easily corrected applying a suitable lorentz boost. as regards resnikoff’s work, we can say that the theoretical clarity and the lucidity of his work have been crowned, after more than 40 years after its publication, by a surprising interpretation: color perception is well suited to be naturally described by the algebraic formalism of quantum theories. in summary, the two “forgotten” articles of yilmaz and resnikoff, clearly posed the bases of a quantumrelativistic color theory capable of explaining into deep and mathematically rigorous terms the phenomena of human chromatic perception. moreover, they add a further step towards the use of hyperbolic geometry in colorimetry as also mentioned by several other authors, e.g. (farup 2014 and lenz et al. 2005). 5. conflict of interest declaration the authors declare that there is no conflict of interest concerning the content of this article. 6. funding source declaration the research activity of n. prencipe is financed by huawei technologies sasu, france, nice research center. 7. acknowledgments the authors wish to warmly thank michel berthier and valérie garcin from la rochelle university, with whom they worked on the analysis of the relativistic and quantum model. we also acknowledge francesco bottacin, antoine guennec, paola iacomussi, dylan russon and nir sochen for several interesting discussions about the mathematical modeling of color perception. 8. short biography of the authors nicoletta prencipe nicoletta prencipe is a phd student working between the mathematics institute of the university of bordeaux and the huawei technologies nice research center in sophia antipolis. she works on the geometry of the space of perceived colors cosupervised by edoardo provenzi and joseph meehan. edoardo provenzi edoardo provenzi is a mathematical physicist working as full professor in the mathematics institute of the university of bordeaux. his main research interest is the geometric modeling of visual perception, color in particular, and its application to image processing and vision. references berthier, m. (2020). geometry of color perception. part 2: perceived colors from real quantum states and hering's rebit. the journal of mathematical neuroscience, 10, 14. berthier m., provenzi e. (2019). when geometry meets psycho-physics and quantum mechanics: modern perspectives on the space of perceived colors. international conference on geometric science of information. springer, pp. 621-630. berthier m., provenzi e. (2021). the quantum nature of color perception: uncertainty relations for chromatic opposition. journal of imaging, 7(2), 40. farup i. (2014). hyperbolic geometry for colour metrics, optics express, 22(10), pp. 12369-12378. geometric models for color perception 56 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130206b r. lenz, t. h. bui, j. hernandez-andres (2005). group theoretical structure of spectral spaces. journal of mathematical imaging and vision 23(3), pp. 297-313. prencipe, n., garcin, v., provenzi, e. (2020). origins of hyperbolicity in color perception. journal of imaging, mdpi, 6 (42), pp.1-19. provenzi, e. (2020). geometry of color perception. part 1: structures and metrics of a homogeneous color space. the journal of mathematical neuroscience, 10 (7), pp.1-19. resnikoff, h.l. (1974). differential geometry and color perception. journal of mathematical biology, 1, 97-131. schrödinger e. (1920). grundlinien einer theorie der farbenmetrik im tagessehen (outline of a theory of colour measurement for daylight vision). available in english in sources of colour science, ed. david l. macadam, the mit press (1970), 134-82. annalen der physik, 63(4):397–456; 481–520. yilmaz, h. (1962). on color perception. the bulletin of mathematical biophysics; 24, 5-29. yilmaz, h. (1962). color vision and a new approach to general perception, biological prototypes and synthetic systems. springer: boston, ma, usa; pp. 126-141. wyszecki, g., & stiles, w. s. (1982). color science (vol. 8). new york: wiley. 42 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130205 is white skin really pink? flesh color as a pink color in western art and culture kévin bideaux 1 1 laboratoire d’études sur le genre et la sexualité (legs, umr8238), university of paris 8, france. bideaux.kevin@gmail.com corresponding author: kévin bideaux (bideaux.kevin@gmail.com) abstract in this article, i determine the shades associated with the idea of a unique flesh color, retrace its history and emphasize its inclusion in the field of pink. i carry out this analysis in a transhistorical and transmediatic way. i will go through medieval texts, literary works, artists’ writing, pictorial and abstractive work, as weel as other cultural productions like fashion, comics or animation. based on this overview, i question the hegemonic position which leads to the long lasting association of pink color with complexion. i will also question this pervasive link with the system of race, since the use of pink indicates only the skin of white people — even symbolically —, understood as the color of the skin in general. keywords flesh color, skin color, pink, race, history of color received 30/01/2021; revised 28/03/2021; accepted 19/09/2021 is white skin really pink? flesh color as a pink color in western art and culture 43 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130205 1. introduction usually used to designate the color of the skin, the term "flesh" is a synonym of “complexion”, or “skin tone”. many links cross path between the flesh color and the nuance we now designate as “pink”, from medieval painting manuals to contemporary arts and fashion trends. more specifically, pink is used as a “flesh color” when it comes to representations of caucasian skin — seen as typical of the so-called “white skin” — in painting, but also in sculpture, cartoons and comics (think of the pink face of disney's cinderella). contemporary fashion and cosmetics also designate by the word “flesh” a set of products whose colors are supposed to refer to the color of the (white) skin. regarding the naming of make-up products, the word “flesh” has been replaced by the term “nude”, which is supposed to refer to a certain idea of “natural”, that is to say without artifice. in literature, authors use pink to describe white skin too. in the poem “à une robe rose” by théophile gautier, the pink fabric of a dress is associated with the “light pink” color of a woman’s skin (gautier, 1850). likewise, from a lexicological point of view, the flesh color is also considered as a shade of pink, after the skin tone of white people (mollard-desfour, 2002; kuriki et al., 2017; zimmermann et al., 2015). however, the color of white skin is really neither pink, nor the same from one individual to another (due to tan, age, health, etc.). this specific generalization and simplification of the complexion of a large social group is actually associated with the concept of race. race is a system of categorization and hierarchization of individuals according to morphological and/or cultural criteria. skin color is one of the main criteria for forming these categories and the category of white people, to which the color flesh pink refers, is then symbolically and socially opposed to a broader set of non-white people [1] (and thus not represented by flesh pink) (blanchard, boëtsch and chevé, 2008). similarly, several contemporary artists used pink as the one color that symbolically refers to the bodily experience common to all human beings. in these cases, pink relates to the flesh understood as mucous or as what is subcutaneous. pink can then signify the organicity of the body, the experience of human life in a philosophical sense, or even the emotions perceived through the skin, therefore providing a psychological dimension to the color. the purpose of this article is to outline how pink became the generic color of the (white) skin, but also how this generic color has become capable of signifying the very concepts of flesh, life and humanity. based on a transmedia and transhistorical study, i will study how pink has become, over the centuries, the color emblem of white skin in western cultures, then symbol of human color taken as a whole. i will also show how this construction intersects with the concept of race, and therefore how pink participates in its own way in the symbolic superiority of white people over non-white people. 2. the flesh color in western history of painting in painting, the term “flesh” is employed as an equivalent to the rendering of the skin. “flesh” is understood as a color term which designates the skin of white people as a whole. it often remains the only dermatological type represented by western artists and approached by treaties on the arts. skin appearance is historically at the center of the concerns of european artists, especially painters. indeed, the representation in painting of the appearance of the color of human skin is a complex and technical challenge, “an inaccessible chimera” (pernac, 2008). ever since the time of the ancient greeks and romans, the complexion was not limited to selecting color, but was rather a question of arranging the shadows and lights in order to provide the illusion of volumes (lichtenstein, 1999), and also to transmit “the expression of the flesh” in all its dimensions, including tactile (diderot and le rond d’alembert, 1766). the qualities of the flesh in paint are also described with the italian term morbidezza which means “suppleness”, “softness”, “tenderness” and “blur”, a range of words which refers to the texture of the flesh and not to its color. it was not until the end of the middle ages that representations of the flesh became a real object of technical study which would occupy artists as much as their commentators for centuries. the flesh became more complex in the duecento with the application of a verdaccio base [2] on which was applied other layers to give the illusion of volume. from the 14 th century, the complexions produced by superimposing layers of colors, sometimes transparent (glaze), had a finesse never obtained until then (laneyrie-dagen, 2006), reaching a striking realism in the works of artists such as jan van eyck (fig. 1) or raphael. still in the middle ages, tempera emerged alongside the encaustic technique which had endured since antiquity, becoming the majority technique. it allowed painters to widen their palette by diluting the pigments in different glue or eggbased solutions. the tempera technique was supplanted by oil painting at the end of the middle ages (around 1500), which allowed painters to obtain the most beautiful flesh in the history of painting (magnain, 2009). is white skin really pink? flesh color as a pink color in western art and culture 44 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130205 fig. 1. van eyck j. (1435) madonna of chancellor rolin. oil on panel, 66 × 62 cm. paris, musée du louvre (1271). photo: the york project, via wikimedia commons (cc 0). fig. 2. lagrenée l.-j.-f. (1767) mercury, herse and aglauros. oil on canvas, 55 × 70 cm. stockholm, nationalmuseum (nm 839). photo: bodil beckman/ stockholm nationalmuseum (cc pd). the exact color of the flesh color in painting remains difficult to define. it actually corresponds to a wide spectrum of shades, often clearer on representations of women (frost, 2010), more or less reddish depending on the emotional state of the character (embarrassment, anger, etc.). several treatises on medieval pictorial techniques offered a wide variety of recipes with multiple mixtures based on green, blue, ocher, white and red, making it possible to imitate the flesh colors (e.g. cennini, c.1390/1859). however, cinnabar red and whitewash are commonly used in these recipes, i.e. shades of pink (red mixed with white) (gettens, feller and chase, 1972). at the end of the quattrocento, flesh color was called incarnato (from the latin carne, “flesh”) and assimilated to red. incarnato later gave the color term “incarnate” which diderot used to describe the color of blood that shines through the skin of the characters in an oil on canvas by louis-jean-françois lagrenée (fig. 2) (diderot, 1876). the incarnate evokes indeed the blood which circulates under the skin and which tints it by transparency, as “under the blow of a categorical imperative of the in-between: between surface and depth” (didi-huberman, 2008). the french lexicographer annie mollard-desfour does not succeed in precisely determining the shade corresponding to the french term incarnat (incarnate): she classifies it in her dictionary of red as “more or less bright red” (mollard-desfour, 2009), but also in that of pink, describing it as a “bright pink” (mollard-desfour, 2002). 3. an explanation about pink as a flesh color the skin is physiologically made up of several layers (epidermis, dermis, hypodermis), bearing each specific structural and chemical properties, but also their own color. the complexion perceived by our visual apparatus then results from the superposition of these layers perceived through transparency. physicist caroline magnain has established a relationship between the dermatological structure of the skin and the pictorial representations of caucasian skin tone, by analogy between the superposition of skin tissues and the layers of matter deposited on the canvas (magnain, 2009). hegel also pointed out that the color of the flesh in painting reflects the different colors of the organic layers of the body: the transparent yellow of the skin, the red of the arteries, and the blue of the veins, to which are added gray, brown and green tones (hegel, 1848). thus, this even apply with abstract works. the pink monochromes of the american painter marcia hafif (roman paintings, 1986) are spectroscopically similar to real skin, due to the superimpositions of successive layers of pigments (red, blue, and yellow) taking up the stratified biological structure of the skin (magnain, 2009). there is therefore a biological reason for the multiple visual representations of white skin by pink shades in western artistic and cultural productions. however, even if we intend to exclusively restrict our focus on white skin, is white skin really pink? flesh color as a pink color in western art and culture 45 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130205 this only outline that all skin tones do not have the same color. accordingly, painters have thoroughly criticized the shades of “flesh color” offered by the merchants of colors for being too pink to be able to account for the entire white complexions (magnain, 2009). the sampling carried out on images answering the keywords “flesh color” and “nude color” collected on the internets allows identifying shades corresponding to the flesh color nowadays [3]. such methodology obviously has many limitations, such as the restriction to digital images or the subjectivity in determining the main color of each image. nevertheless, the point is not as much to define what is flesh color or nude, but more to circumscribe a non-exhaustive set of colors corresponding to the effective uses of these designations. moreover, the collecting of digital images that this methodology implies seems appropriate, since the designation “flesh color” is nowadays mainly used in fashion (especially underwear) and cosmetics (no photograph of painting is included in the sample) [4]. this analysis thus shows that the flesh (or nude) color corresponds to a wide spectrum of shades, which includes a certain amount of pink or pinkish shades, but also a lot of brown, orange, yellow and gray ones (fig. 3; fig. 4). we observe also a simplification of numerous skin tones to the single term “flesh color” (which is often describes as pink), analogous to the simplification of people with caucasian complexions to the single designation “white people” (who are anything but white). fig. 3. color chart obtained from the collection of hundred pictures answering the keywords “flesh color” on the internets. january 2020. photo: k. bideaux (cc by-nc-nd). fig. 4. color chart obtained from the collection of hundred pictures answering the keywords “nude color” on the internets. january 2020. photo: k. bideaux (cc by-nc-nd). 4. flesh color, race and whiteness the existence as well as the recurring use of a single term to designate all complexions, leads me to question flesh color in articulation with the concept of race. skin color has indeed always participated in the construction of individual and collective identities, related to the racial system of classification of individuals according to their complexion (blanchard, boëtsch and chevé, 2008). mechthild fend specifies that it is no coincidence that the term “skin color” appeared in the second half of the 18th century simultaneously in theory of french art and racial anthropology: both discourses grant the symbolical and social superiority of white skin as the universal ideal and standard of beauty (fend, 2005). white skin has indeed been associated since antiquity with beauty — especially the female one (pelletiermichaud, 2016) —, and youngness (garo, 2008). it is still deemed as a beauty ideal to be reached in black african communities (emeriau, 2009). the blushing skin of embarrassed white women has also become a means for painters to bring eroticism to their canvas, also linking white skin to desire and sexuality (fig. 5). in addition, the history of western art is also ethnocentric: critics and institutional exhibitions or acquisitions visibilizes the production of caucasian artists, who themselves have mainly represented caucasian characters (fernandez-sacco, 2001). furthermore, when non-white people were depicted in paintings, they have is white skin really pink? flesh color as a pink color in western art and culture 46 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130205 historically been portrayed through a racial and colonial perspective (lafont, 2019; lewis, 1996). fig. 5. honthorst (van) g. (1625) smiling girl, a courtesan, holding an obscene image. oil on canvas, 81,3 × 64,1 cm. saint-louis, saint-louis art museum (63:1954). photo: saint-louis art museum (cc 0). whiteness not only dominates in the field of representations, but also gives the impression that it is a norm. this last element would explain why the color term “flesh” was constructed only on the color of white people, given that they represent a majority or even universal model. we can therefore say that the flesh color has a relationship with whiteness, a concept that designates the white social, cultural and political hegemony faced by ethno-racial minorities, as well as a mode of problematizing social relations of race (garner, 2007). using flesh color in cultural and artistic productions, as well as considering that everyone has the same complexion, i.e. a white one, could be consequently considered as a symbolic violence (bourdieu and passeron, 1970) for non-white people. this enduring vision still allows the maintenance of an unequal hierarchy based on race, by incorporating social, cultural and aesthetic classifications according to skin color. the french anti-racist activist rokhaya diallo recalled for example that pink-beige color of sticking plasters, as well as the “nude” trend in fashion, was designed for the comfort of white people. these plaster indeed matches their skin color, while they are extremely visible on black skins (diallo, 2018). 5. flesh color as “human being” symbol sometimes, pink used as skin color by contemporary artists can bear a symbolic dimension, which is dissociated — at least in part — from the strict representation of the skin. it is a question of transmitting the idea of flesh/skin, and of associating a precise symbolism with it. for example, the impasto of colored plaster by the italian artist ettore spalletti are mineral and powdery, and at the same time give an impression of life through a play of depth and subtle nuances. his work shows the rendering of the flesh that only oil usually does. spalletti himself rightly referred to the skin when talking about his work, stressing the link between the pigment and dermatological variations: “pink has no fixity: it is the pigment of the skin that changes according to our moods” (boudier, 2018). as many previous studies have shown, colors and emotions are indeed linked (simmons, 2011; clarke and costal, 2008): theorist of affects brian massumi explains that colors are capable of directly affecting the body, “[r]eflexively (that is to say, non-reflectively) in an immediate nervous response” (massumi, 2005). the skin is therefore an interface between the inside and the outside, at the intersection of the self and the other and thus becoming a field of expression, experimentation and confrontation (dagognet, 1998). in the film pieles (2017), the spanish director eduardo casanova follows in their intimacy several protagonists with bodies considered to be out of the ordinary [5]. the movie explores various themes such as desire, reification, discrimination, rejection or the search for authenticity. the skin in hinted by the title, and the omnipresence of pink in the decorations, costumes and visuals of communication works as a way of symbolizing skin as a metaphor for emotions and intimacy.. the use of pink as the color of the flesh can therefore signify the affects and emotions that pass through the flesh/skin. flesh thus becomes a concept that artists use as a symbol and no longer for the purpose of representing the skin as an organic part of the body. pink in the work of french artist yves klein particularly embodies a highly accomplished conceptualization of flesh. if he is mainly known for his ultramarine blue monochromes, he has however also produced numerous pink monochromes (named monopinks) evoking the skin. is white skin really pink? flesh color as a pink color in western art and culture 47 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130205 klein’s pink refers to material world, in opposition to the immateriality of the blue. the flesh is thus thought not in terms of corporality, as making direct reference to the body and its organicity, but to the flesh as a concept. it refers to materiality perceived as an experience, not as a form (morineau, 2006), echoing the maurice merleauponty’s concept of flesh, thought ontologically as an extension of the body, as a part of the world (1979). other artists such as the french marguerite humeau (exhibition foxp2 at palais de tokyo, paris, 2016) [6] or the austrian pamela rosenkranz (installation our product, 2015) [7] have developed this same discourse by using pink as a symbol of the flesh, understood as a common material shared by all human beings. in short, these artists refer to pink as a symbol of life and humanity. this close association between pink (as the very color of flesh) and human being as a whole was also the grounds on which the esoteric anthroposophical current based its theory. its creator, rudolf steiner, did not strictly write a theory of colors. he nevertheless proposed to assign a meaning to each colors, understood as representing the forces in action in nature: green as the color of plants, white that of light, black that of darkness and the peach-blossom color (pfirsichblütfarbe) that of the human soul. among them, peach-blossom is a shade of pink that steiner described with reference to the “color of human flesh, which of course is not exactly the same for different people”, admitting therefore that pink cannot signify all skin tones (steiner, 1921/2010). however, can we really disconnect the flesh color as a symbol of humanity, from the flesh color representation of white bodies? english artist derek jarman wondered whether steiner would have chosen the color of the peach blossom as the color of human existence if he himself had been a black man (jarman, 1994/2003). we could indeed wonder if the pink flesh as being able to designate the whole of humanity would not have to do with the whiteness of those who make this association (as a reminder, klein, humeau and rosenkranz are also white people). 6. pink as “organic flesh” color perhaps it is necessary to think of the flesh not as indicating the color of the skin, but rather as indicating to what lies below: the muscles and organs, or even the mucous. the art historian dominique grisard said for example about the series second skin (2017) of the swiss artist nici jost that “[p]ink is both skin-deep and flesh and blood” (grisard, 2019). the artist herself says that pink is a color of “equality and unification” because no matter the skin color, size, ethnicity or gender, our mucous are all the same color (jost, 2016). however, if the mucous, certain organs or certain meats can effectively be pink or considered as pink colored, it is more the red, which represents our organic interiority: that of the blood coloring the muscles, flowing when the body is opened or injured. even when the flesh thought as subcutaneous organic matter is represented in pink, the red of the blood is always intrinsically associated with it, both visually and symbolically (salamandra, 2018). 7. conclusion this analysis of the connotations associated with the color flesh reveals the way in which the relations of power (here of race) between dominant and dominated are involved in the history of colors as well as enrich their symbolism. if the use of pink as flesh color in the representations of white bodies corresponds to a logic (admittedly simplified) of transcription of reality, its use as a symbol of complexion in general is more problematic. flesh color is effectively part of a racial perspective, shaped by history and social representations, which we cannot ignore. similarly, while pink can signify flesh considered as what is common to human existence, it cannot claim any meaning of universality because its symbolic construction is anchored in a white western art history. this is not to say that artists, theorists or even marketers are racist, but more to contextualize our symbolic systems, the way we deploy them — in particular through color —, and their real effects on individuals. the ambition of this article was to propose a transmedia and transhistorical vision of the uses of the “flesh color” in the art and the western culture. the conciseness of the paper's format has forced me to proceed to a synthesis of the examples presented and to a simplification of the analyses. additional investigations are therefore necessary in order to highlight the variations in the use of flesh color, according to the periods, the geographical areas, but also according to the support. conflict of interest declaration i wish to confirm that there are no known conflicts of interest associated with this publication and there has been no significant financial support for this work that could have influenced its outcome. funding source declaration no funding was received for this work. is white skin really pink? flesh color as a pink color in western art and culture 48 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130205 acknowledgment i would like to thank marie-dominique gil and olivier thuillier for proofreading and translation assistance, as well as floryan varennes, barbara fulneau and valérie agneray for their advice and wise eye on the subject. short biography of the author kévin bideaux is phd candidate in arts and gender studies at the laboratoire d’études de genre et sexualité (legs, umr 8238, university of paris 8). his doctoral research focuses on a better understanding of the uses of pink in the visual arts, marketing, sciences and politics. he is also a visual artist, working essentially with the color pink. notes [1] this includes black people, but also those sometimes referred to as “brown people”, a term that refers to people from the middle east, north africa and the indian subcontinent. [2] verdaccio is a mixture of black, white, and yellow pigments resulting in a grayish or yellowish soft greenish brown. [3] i used the methodology used by kate hughes and donna wyatt to determine the nuances associated with breast cancer (hughes and wyatt, 2015). this involves determining skin tones from a sample of digital images collected from internets, responding to a specific keyword. i collected about a hundred unique images responding to the keywords "flesh color" and "nude color" (identified using the google image search engine), i then determined in each image the significant shade of flesh using an image editing software, and i finally classified each of these shades according to its hue (h), its saturation (s), and its value (v), the hsv model being particularly relevant when it comes to digital images. after having carried out this sampling work, i gathered and condensed all the shades obtained into two hundred-color charts. [4] these images are most often disseminated on the internet by commercial sites or photographs of haute-couture shows or celebrities. [5] a young woman born without eyes is a prostitute to support herself, and counts among her clients an obese woman who lives her lesbianism in secret. a pregnant dwarf is the exploited star of a children's show in which she plays a pink bear. a woman with a deformed face is in a relationship with a man whose skin has suffered severe burns; another young woman has a deformity that has caused her mouth and anus to be inverted. one last character is an exception: a teenager with an able body who dreams of losing his legs to become a mermaid. [6] for this exhibition, humeau created white sculptures in the shape of elephants, which she arranged on a pink carpet. the carpet was made especially for the exhibition, from a recipe developed by the artist using the chemical components of a human being (carbon, oxygen, sulphur, calcium, etc.), of which she respects the percentages and quantities (santa lucia, 2016). [7] this installation consists of an impressive basin filled with two hundred and forty thousand liters of a pinkish-colored liquid. the color chosen by rosenkranz is based on the standard colors of cosmetic industry foundations, which are understood from their shades to be mainly designed for whites people only (launay, 2015). references blanchard, p., boëtsch, g. and chevé, d. (2008) ‘corps, couleurs, images : l’identité dans tous ses éclats’, in blanchard, p., boëtsch, g. and chevé, d. (ed.), corps et couleurs. paris: cnrs, p. 7-16. boudier, l. 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(1921) das wesen der farben. grundzüge einer geisteswissenschaftlichen farbenlehre für das künstlerische schaffen. reprint, provo: rudolf steiner online archiv, 2010. zimmermann, m., levisen, c., beck, þ. g. and scherpenberg (van), c. (2015) ‘please pass me the skin coloured crayon! semantics, socialisation, and folk models of race in contemporary europe’, language sciences, 49, p. 35-50. doi: 10.1016/j.langsci.2014.07.007. 32 color culture and science journal vol. 13 (1) doi: 10.23738/ccsj.130104 color in architecture among futurism, neoplasticism, rationalism (and more...) anna marotta department of architecture and design, politecnico di torino, torino, italy. nannarella.marotta@gmail.com abstract in the first decades of the twentieth century, the relationships between the culture of color and all forms of creativity were intense. in general between futurism and rationalism if chromatic theories, trends and "fashions" are clearly recognizable in sectors such as graphic and painting, these are less evident in the complex of architecture. the futurists immediately appeared open to international contacts: prampolini, in the area of french purism; marinetti, close to karel teige and the new czechoslovakian researches; paladini to the russian imaginism, while carmelich is the trait d’union with the yugoslav constructivist area. in all cases, the roots of bauhaus appear central, even with the fertile role of generator for chromatic theories (matotta, 1999), with itten, klee, kandinsky, hinnerk sheper, albers (fig. 1), but van doesburg as well. on the basis of studies on the history and theories of color, this essay intends to re-establish albeit through still largely incomplete fragments the network of diffusion developed in futurism, from futurism (between theory and practice, knowledge and experience), to start possible comparisons through analogies or discrepancies, and to grasp some developments in architecture, in the contemporary debate, or in subsequent moments. from this point of view, both in coeval and in subsequent periods, the figure of alberto sartoris is confirmed illuminating if we take into consideration his intuitive ability and his cultural background, even in the field of color. combining cultural or speculative aspects with experimentation in the architectural design, his national and international contacts in the field of color, by taste and in the futurist period, later matured with rationalism (including all the derived and/or connected "isms") are also valuable. keywords contemporary architecture, futurism, neoplasticism, rationalism, bauhaus, theories of color received 09/02/2021; revised 17/02/2021; accepted 28/03/02 color in architecture among futurism, neoplasticism, rationalism (and more...) 33 color culture and science journal vol. 13 (1) doi: 10.23738/ccsj.130104 1. futurist manifestos as a cultural strategy one of the typical traits of futurism lies in the copious production of manifestos (fig. 1) intended as a real cultural strategy and for which reference is made to the chronology already collected by the author (marotta, 2019). in 1914 antonio sant'elia (fig. 2) published the manifesto of futurist architecture in milan: the city is placed at the center of interest and is conceived as a symbol of dynamism and modernity. the paper does not explicitly refer to color, nor to its historical and theoretical foundations, nor to the relationship between architecture and color. the second technical manifesto for futurist painting is much more interesting (1911), where for the chromatic aspects it is explicit a precise reference to "style, in the belief that the new painting must be based on the decomposition of color, of divisionist origin. the breakdown of colors (defined by them as «congenital complementarism»), not only must enhance the sensation of dynamism, but must contribute to that new spatiality where it is precisely light, together with motion, that makes objects interpenetrate one another". 2. the neoplasticism by gerrit thomas rietveld and teo van doesburg in those years, from bauhaus to constructivism, up to neoplasticism passing through de stijl, (and vice-versa) mondrian, van doesburg, van der leck, rietveld, vantongerloo and huszár expressed their individual opinions about color. in any composition, rietveld conceives color in an ancillary (almost supportive) term, but with an essential function in individual perception, reinforced by a captive role, of the primary colors especially. in addition, it was he whom created the schroeder house in utrecht (1924), an authentic architectural emblem of the movement: the decomposition of space into planes is underlined here by the use of primary colors, pure and saturated on the same surfaces (fig. 3). in a game of “pure” rectangles and colors, rietveld creates a perfect synthesis of the theories of the movement, where the furnishing objects and the architectural structure embrace the same constructive principles. the house develops on two levels, based on four fundamental elements, comparable with the theories that began at the bauhaus: primary elements in white color that determine the shape and structure of the house; flat elements in gray or white color aimed at defining the relationship between inside and outside; linear, vertical and horizontal elements architraves, pillars, drainpipes in yellow, red and blue combined with white, gray and black; functional elements windows, doors, railings, external staircase and skylight in black and white. it should be noted that as early as 1921 johannes itten (at the weimar school since 1919) had made a first model of color (marotta, 1999, pp. 45, e 134-135). from the same years (1919-21) his “fire tower”, derived as is known from the complex and in-depth intertwining with the geometric and mathematical disciplines. on the contrary, huszár and van doesburg adhered to the theories of wilhelm ostwald (marotta, 2018). the latter created the color construction in 1922: it is a work of which zevi writes: "the wall partitions are no longer silent, they have no weight, they can be dismembered into minor rectangles chromatically distinguished by the basic colors.” (marotta, 1999, p. 76). these are the results of the rigorous formal and functional research that van doesburg had conducted with colleagues such as cor van eesteren and of which we can recall what he had written in 1923: "we examined the laws of color in space and duration, and we found that the balanced relationships of these two elements eventually lead to a new and positive plastic” (marotta, 1999, pp. 24-25). in 1927, according to a similar but more complex concept, theo created (together with hans arp and his wife sophie taeuber) the café aubette in strasbourg, one of the most ambitious designs of the architectural culture of the time: here his spatial vision through formal synthesis and pure colors is evident (marotta, 2019). again, by de stijl, while van der leck considered the color essentially as a medium to achieve greater control in formal synthesis, vantongerloo finally elaborated a chromatic theory, conceived through pseudomathematical formulas in order to match music to colors, and developed seven of it systematically related. 3. chromatic and geometric matrices from bauhaus in 1919 because of an invitation by hans richter and viking eggeling (siggillino, 1998) (whose filmic experiments between color and geometry are known, such as diagonal symphony or orizontal/vertical orchestra) van doesburg went to berlin, bringing with him the first abstract films, the collection of the de stijl magazine and pictures of the neoplastic works (zevi, 1974, pp.16-17). on christmas night, in bruno taut's house, van doesburg met adolf meyer and walter gropius, (as teo remember) (van doesburg, 1925) with color in architecture among futurism, neoplasticism, rationalism (and more...) 34 color culture and science journal vol. 13 (1) doi: 10.23738/ccsj.130104 the aim of being included in the teaching staff of bauhaus. in 1922, he also collaborated with the magazine dada mécano together with schwitters, arp and tzara. his painting was confirmed in the combination of primary colors with elementary geometric shapes: lines, diagonals, squares, to enhance spaces and architecture. in 1925, the bauhaus published grundbegriffe der neue gestaltenden kunst in munich, a paper about the basic principles of the plastic arts. 4. the futurist color by nicolay diulgheroff the bulgarian nicolay diulgheroff came to italy, in particular in turin (belloli, pinottini, 1987). he trained in vienna in the 1920s at the kunstgewerbeschule in dresden (where he met kandinsky, who was decisive for him also for the chromatic theories). he then went to the bauhaus he spent time with johannes itten, whom soon became one of the best-known theorists of color. in turin, he enrolled in the scuola superiore di architettura, at the accademia albertina, where he left traces and documentation (the writer now investigates these, in order to better recognize the chromatic components in the design activity: the current constraining conditions have unfortunately forbidden the consultation). nicolay met fillia (luigi colombo), close to the constructivists: in 1931 he was significantly present in his book la nuova architettura [8], which cites together with the futurists also authors of other tendencies: gropius, le corbusier, sartoris. this is where the premises of futurist mechanical art were born, the manifesto signed by pannaggi and paladini in 1922, followed the one on architecture by sant’elia. he signed architectural designs (villino montaldo, or “il faro”) (fig. 4 d), but also interiors, as for exhibitions, as well as graphic and pictorial activities. in albissola marina one of his significant works: casa mazzotti, (fig. 4 a, b, c) for tullio mazzotti (called tullio d'albissola by marinetti) as his home and ceramic laboratory, with an adjoining shop to display and sale. it is one of the rare examples of futurist housing still intact, designed and built under the direction of the architect without undergoing changes or additions over time. it currently houses the ceramiche mazzotti company. the formal and structural language connotes the "dynamic" futurist style: the projecting roofs at the entrance to the shop and on the facade of the residence, the large windows of the house and the ones curves of the stair space, the numerous metal railings, the harmonious play of lights and shadows, the curved parts of the staircase and the shop, the protusions that frame the openings and the rounded corners. on the other hand, the proportion of the volumes and their division according to the functions for which the villa was built is rationalist: house, ceramic laboratory and adjoining shop to display and sale. in 1930, he wrote to his friend his testament about his own theory of architecture: "architecture is beautiful and superior to the other arts, because it creates living and harmonious organisms in everything... the design of the new mazzotti factory is of a modern and futurist style, but of a futurism of which we should not be very frightened because "we are very, very far from prampolini's futurism". in our design there is only "simplicity, logic, proportion, economy", the rest is harmony and good taste” (belloli, pinottini, 1987, pp.714). the colors suggested by tullio (artist and ceramist of great cultural allegiance) stand out unusual on the ligurian promenade even nowadays: they were inspired to nicolay by the beach and the marine location for the choice of colors, but also by the ceramics by albissola. on july 26th, 1932: "i chose three tones: straw yellow (almost white) for the front of the shop that stands out well in the plastic complex of the house that is in blue gray color instead, on which the tower of the staircase is painted all in earthy yellow or vice versa, and fits in the central block” (belloli, pinottini, 1987). the book by fillia in 1932 (colombo, 1931, pp. 68, 73, 75) reports the name diulgheroff several times. 5. color by alberto sartoris, futurist, rationalist and functionalist architect alberto sartoris (turin, 1901-1998) rationalist architect, then functionalist architect, has a profile with strong traits linked to the futurism. he trained in switzerland, at the école des beaux arts in geneva, he made his artistic debut as a painter, continuing his studies in paris. in 1920 he met marinetti in geneva, became his friend as well as his futurist disciple [10]. together with terragni, figini, rava, pollini, frette and larco (il “gruppo dei sette”), he signed the official manifesto of italian rationalism, which later became the italian movement for rational architecture (miar). he adhered to futurism according to a free, independent relationship, with numerous architectural designs and to the editorial staff of the periodical "la città futurista". he took part to represent italy at the international congress of modern architecture in switzerland in 1928 (a conference directly influenced by le corbusier), and in the same year he participated at the 1st exhibition of futurist architecture in turin. he was friend with le corbusier and alvar aalto and gropius (with whom he developed the study of a new architectural language color in architecture among futurism, neoplasticism, rationalism (and more...) 35 color culture and science journal vol. 13 (1) doi: 10.23738/ccsj.130104 based on geometric form as an absolute and structuring value). he published in 1930 a monograph about antonio sant’elia. in the1941 he joined the "gruppo primordiali futuristi sant’elia" proposed by the philosopher ciliberti, and conceived as intellectual coordination in the field of "modern" art. he punctually takes up the fundamental themes of the way of thinking and chromatic project, ranging from theoretical aspects to project practice, even in the architectural interior, as a lucid critical filter in his volume dated 1990: tempo dell'architettura (sartoris, 1990) (to be compared, moreover, with his founding encyclopèdie de l'architecture nouvelle dated 1948) (sartoris, 1948). these are the topics dedicated to the theme: polychrome dynamism, mystical measurement, science and measurement of color, polidimensional exaltation, fourth dimension. in the first case, the "mystical measurement" (referring to places of worship), it requires psychological colors in his opinion. "the functional windows he says will therefore be formed by special superimposed glass, engraved, doubled, screwed, frosted, silvered, gilded, with new mixtures, and realized with the tones of the most audacious polychrome theories" (in this regard, note the very important and conclusive experiments by the hungarian painter ladislas moholy-nagy and those by the german painter josef albers, with the implied theoretical implications)”. in the chapter on science and values of color, he agrees with ugo maraldi (maraldi, 1943), who examines colors and shapes of sounds studying the prodromes of a new art for a future man, according to «images created by the alchemy of words and visible harmonies of musical chords» (marotta, 2019). in sartoris' way of thinking and project, in his systematic and complex vision of color, a strong character component is the relationship between his futurist training and the neoplasticism. the in-depth knowledge of the elementary architecture and of the neoplasticist pictorial field, offered to sartoris the starting point for a thorough investigation of the relationship between architecture and color. in the unique issue of circle. international survey of constructive art (sartoris, 1937) published in london in 1937 by j. l. martin, ben nicholson and naum gabo, sartoris published a piece entitled color in interior architecture, not sufficiently considered by critics yet. the focus is on the need to reintegrate color in the interiors of the new architecture, putting an end to the reaction against the nineteenth-century abuses, which determined the monochrome of modern architecture in its first phase (sartoris, 1937, pp.212-214). sartoris also talked about it in its application forms: “my other experiences concern a different method: the neoplasticist procedure. it treats the same wall with various colors (always joined together by grays, whites and blacks), while preserving the specific character and destination of the environment, accentuating it or transmuting its correlationships if the architecture requires it. in this case, i prefer to use pure, fundamental colors, such as yellow, light and dark turquoise and red, when the dynamic method uses all the known ranges of colors and those that the invention preconize" (sartoris, 1937 and sommella grossi, 1993). from the chapters on polydimensional exaltation and the fourth dimension, sartoris confirms some concepts: "in the neoplastic compositions, which pursue, for example, the aim of constituting the joyful atmosphere of a specific environment, with the use of pure fundamental colors, together with whites, blacks and grays, the functions to be represented plastically are very different. the very function of the local no longer requires complete, absolute unity, but the dismembered, fragmented, diaphragmatic faction. it is for this reason that the composition made with turquoises, yellows and reds (which can also be represented by plastic materials or with artificial light effects) combined in relatively small dimensions, but in numerous quantities, has been treated by categorically breaking the bare walls, while not destroying the volume". here too, the reference (among other things) to rietveld, van doesburg and mondrian is evident. however, sartoris' interest in neoplasticism (with the desire to confront with van doesburg in particular) is also reflected on a speculative level regarding the influence of futurism on rationalism (concerning italy). the complexity of the relationships between the various spheres of the international avant-gardes is based on constant confrontation and intellectual speculation. in this regard is exemplary the much debated question of the futurist contribution to italian rationalism, in the light in particular of the essay by sartoris, sent to van doesburg, le rationalisme italien (1929), whose manuscript is kept at the van doesburg archive (l’aja) (pianzola, 1990 and sommella grossi, 1988). 6. critical and comparative synthesis: similarities and differences in the awareness of the different positions, in the developments of the various movements over time, we can summarize some possible general terms (if not real parameters) for a first comparative synthesis: chromatic color in architecture among futurism, neoplasticism, rationalism (and more...) 36 color culture and science journal vol. 13 (1) doi: 10.23738/ccsj.130104 theories, "chromoplastics", pure color (also called "spatial color" by van doesburg), “chromatic axonometries”. in a first hypothesis of comparison towards possible analogies and discrepancies it is possible to confirm the relationship with colour theories as a basic parameter: itten (especially for diulgheroff, (marotta, 1999, pp. 31, 76), and in the "anticipatory experiences" of rietveld); ostwald (at which van doesburg adheres to); goethe and albers (favored by sartoris). furthermore, for van doesburg and sartoris, a substantial convergence is confirmed in the deepening of contemporary studies and research in the optical field and in the psychology of visual perception [16]. also in relation to the aforementioned approach, (here obviously in an ex-post reading) the renewed relationship between form, color and structure (also visual) is strengthened in the dimension of the space thought, designed, represented, acted, perceived. in this sense, a coherent contribution can be found by van doesburg, in the comparison and application of the concept of "pure” (or "spatial") color, conceived according to a" chromoplastic "vision: teo also hypothesizes "a new way of designing,engaging deeply through color in the relationship of two-dimensional signs with volumetric and spatial reality, against the usual system of tracing the plans, then the sections and finally the perspective facades" (zevi, 1974) and again affirms: "a balance cannot be found between space and time if not in chromoplastics, that is, in the pictorial composition of three-dimensional space” (van doesburg, 1925 and bassegoda nonell, 1982). but the same “pure colors” (as understood above) are enriched with wider and deeper values: “without color, architecture is without expression, it is blind […] obviously architecture does not become art through the use of color [...] but it is as indispensable to man as light” (van doesburg, 1925). and van doesburg concludes that "in modern architecture the surfaces ask to be animated, that is, to be composed with the help of pure color, the color of space" (van doesburg, 1925). a consequent phase (as a subsequent development) can be identified by the representation of spatial colors in the axonometric dimension, taken not only as a mere graphic tool, but as a laboratory of intellectual speculation for the project. in these applications, similarities and convergences can be found in the visual and chromatic results (shared between diulgheroff, rietveld, van doesburg, and sartoris) through the intersections (if not real programmatic choices) with the ittenian contrasts, above all in the first instance in the confirmation of pure or "spatial" colors, just mentioned. this is confirmed even more clearly for alberto sartoris (fig. 5): whether it is "chromatic axonometries" (versari, 1997) or axonometry "as a project" (reichlin, 1979), or "integrated", according to besset's thought (besset, 1992) the color in the architectural space and in its representation it lives "no longer on the superficial level of collaboration between disciplines, but on the fundamental level of the fusion of the elements of any creation" (beguin, felley, 1992). the documented request for a meeting with van doesburg (pianzola, 1990 and sommella grossi, 1988) is proof of the extent to which the turin architect was consensual with teo's guidelines. for sartoris, the integration of all the arts and the various forms of knowledge is valid, but above all color "is the fourth dimension of architecture" (sartoris, 1990, pp. 100102) which he divides into three approaches: "the first coming from dutch neoplasticism and french purism mainly used by painters such as mondrian and ozenfant characterized by the exclusive use of primary colors only, combined with white, black and different shades of gray" (sartoris, 1937).this is the method he applied in the first "polychrome axonometries" from the 1920 (pianzola, 1990, p.71). the second “dynamic” method which can be linked to le corbusier's theories and only partially to french purism contemplates the possibility of using a wider chromatic range (take for example the hermitage circle at epesses in switzerland). in this sense, the use of color once again highlights sartoris's desire to build a “true artwork” through drawing and color, as evidenced by the documentation preserved in the same club. finally, the "functional" method allows the use of the entire chromatic range: the colors must be chosen according to specific psychological criteria (and here the reference to his interest in this type of study which we have already mentioned is fundamental also shared by van doesburg), to generate (also in physiological and perceptive ways) an atmosphere programmatically aimed at inducing targeted sensations according to the intended use in individual environments. as an example, we recall the morandi-pasteur house in switzerland (1935). a long process that is a confirmation of the concept of color as a "fourth dimension", capable of triggering the dynamism and interactivity of the environment, reinforced by the success of his furniture ensembles, to which he had dedicated himself since 1928. 7. conclusions in the period we have considered, in a continuous exchange between art, architecture and theories (significant, for example, itten’s experiences are confirmed), color is one of the approaches to better build, color in architecture among futurism, neoplasticism, rationalism (and more...) 37 color culture and science journal vol. 13 (1) doi: 10.23738/ccsj.130104 control and communicate (through visual language) structures and harmonies in three-dimensional relationships and in their respective balances in spacetime. but that's not enough: it itself becomes a system and mental model structuring the design process in its complexity. from this perspective, architecture becomes an effective and complete expression of all experiences in perfect coherence with the objectives identified by the various authors. thus, each of them "draws", represents and shares its own "chromatic thought" making it (as berenson would observe) tactfully palpable, in a "multisensory" way, in a new dimension that is no longer limited to "anti-decorative", but almost a "special effect” of that period: a new, “manifesto ideal”, all projected towards the future, from which new questions will arise, for new research, and therefore still relevant. because, as zevi observes about rietveld’s chromatic culture, "when a 'linguistic' system is adopted outside the circle of the movement that produced it, by architects of very different sensibilities, it means that it is not a fashion, but a permanent parameter of a figurative culture" (zevi, 1958). fig. 1. chromatic matrices between futurist and bauhaus, theories and practice. color in architecture among futurism, neoplasticism, rationalism (and more...) 38 color culture and science journal vol. 13 (1) doi: 10.23738/ccsj.130104 fig. 2. a futurist vision: city designs by antonio sant’elia. his futurist architect manifesto (1914) sets forth the principles of this new tendency: the city is placed at the center of interest and conceived as a symbol of dynamism and modernity. despite the wide and generous use adopted in the representation of his designs, the paper does not explicity refer to color, nor to its historical and theoretical foundations, nor to the relationship between architecture and color. color in architecture among futurism, neoplasticism, rationalism (and more...) 39 color culture and science journal vol. 13 (1) doi: 10.23738/ccsj.130104 fig. 3. the neoplasticism of gerrit thomas rietveld in schroeder house (1924). a.symmetry and repetition. “instead of symmetry, in the example the architecture proposes the balanced relationship of unequal parts, (by position, measure proportion, etc.) balanced by their functional character. the conformity of these parts is given by the overall balance and not by the equality”. (zevi, 1937, p. 280); b.-the chromatic system in the building structure. it is often cited as the culmination of neo-plasticism, as a mondrian painting made in three dimensions: especially from the prins hendriklaan side, it reveals many relationships with mondrian's paintings. but this does not necessarily imply that the building is a translation of a mondrian in architecture, or that the structural typology and the architectural form depend on uncritical automatisms; c-d-e-f. exchanges between art, architecture and theories. rietveld met mondrian by chance; but in 1918 in the redblue chair rietveld had combined lines, primary colors and planes in advance of mondrian's works of that period. analyzing the works of rietveld and mondrian, we realize that the situation is more of confrontation than of influence; (e) mondrian, composition with white, red and yellow 1936; (f) mondrian, composition with red, yellow and blue, 1926. color in architecture among futurism, neoplasticism, rationalism (and more...) 40 color culture and science journal vol. 13 (1) doi: 10.23738/ccsj.130104 fig. 4. color by nicolay diulgheroff's futurism (by fillia, 1931; by marotta, 2019). a. villa mazzotti albissola photographic view and façade (marotta, 2019); b. c. villa mazzotti perspective drawings; d. “lighthouse for the victory of the machine” axonometric projection; e. design for a high school, axonometric projection; f. villa cittadina perspective drawing. the colors suggested by tullio mazzotti (artist and ceramist of great cultural allegiance) stand out unusual on the ligurian seafront still nowadays: they were inspired to nicolay by the beach and the marine location for the choice of colors, but also by albissola's ceramics. "i chose three tones: straw yellow (almost white) for the front of the shop that stands out well in the plastic complex of the house, in a blue gray color instead, on which the staircase tower is painted all in earthy yellow or vice versa and fits into the central block". july 26th, 1932. (belloli, pinottini, 1987). color in architecture among futurism, neoplasticism, rationalism (and more...) 41 color culture and science journal vol. 13 (1) doi: 10.23738/ccsj.130104 fig. 5. color by alberto sartoris, futurist, rationalist and functionalist architect. a. cathedral notre-dame du phare, fribourg, switzerland, 1931 b. picture of alberto sartoris; c. villa for romain brun, lausanne, switzerland, 1934 (by cristiano); d. residence d'un architecte, side south east east, florence, italy, 1942 (in sartoris, 1948). e. residence d'un architecte, side north-west, 1942 f. residence d'un architecte, interior details of the atelier, 1942. for sartoris above all color "is the fourth dimension of architecture", which he divides into three approaches:"the first coming from dutch neoplasticism and french purism; second “dynamic” method (linked to le corbusier's thinking); finally, the "functional"(based on specific psychological criteria) allows the use of the entire chromatic range. color in architecture among futurism, neoplasticism, rationalism (and more...) 42 color culture and science journal vol. 13 (1) doi: 10.23738/ccsj.130104 8. funding source declaration this research did not receive any specific grant from funding agencies in the public, commercial, or not-forprofit sectors. 9. conflict of interest the author declares that nothing has affected her objectivity or independence in the production of this work. there are no actual or potential conflicts of interest, including financial, personal or other relationships with other people or organizations. 10. short biography of the author anna marotta architect, full professor of representation at the department of architecture and design (dad) of politecnico di torino. ph.d in conservation of monuments. for years she has dedicated his interests to surveying, reading and communication (in a cultured and specialized sense as the result of the culture of vision) of architecture, cities and landscapes, even in the most up-to-date events, including those relating to color treated according to the "comparative theories". she is the author of many publications on the topics of his research, many of which are recognized in research projects of national interest. she teaches even internationally disciplines related to drawing and representation fields, including visual communication, laboratory of drawing and architectural survey, atelier of representation and project, drawing from the true and the imaginary. since 2012, she is a member of the scientific committee of the gruppo del colore and she is a member of the presidential committee of the associazione nazionale colore. references marotta, a. 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(1958) tomas gerrit rietveld, in “forum”, n. 3, pp.76-77. 47 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140106 the start of the rainbow: possibilities of color motion photography for the amateur [1] louisa trott university of tennessee, knoxville, united states of america, ltrott1@utk.edu abstract this paper provides a chronology and summary of amateur cinematography’s early color history. drawing primarily on articles and advertisements in amateur movie makers' publications and the popular press in the united states and europe, it summarizes the additive color motion picture processes, effects, and equipment available to amateur cinematographers in the 1920s and ‘30s. the paper concludes that while these additive processes might appear primitive and flawed in comparison to later processes and technologies, they are worthy of celebration and appreciation for their ingenuity and unique characteristics. keywords color motion picture film, amateur motion picture film, additive color processes, historical color processes received 03/11/2021; revised 03/01/2022; accepted 25/01/2022 the start of the rainbow: possibilities of color motion photography for the amateur 48 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140106 1. introduction the earliest era of amateur movie making offered an inventive array of color possibilities for the film enthusiast. from the simple addition of colored filters on a projector to the delicate hues of lenticular kodacolor, and later the accessory-free magic of dufaycolor’s réseau [2]. the market for amateur movie-making quickly flourished after the introduction of 9.5mm and 16mm gauges in 1922 and 1923, respectively. new publications emerged dedicated to the amateur filmmaker, and industry and professional journals introduced amateur sections, providing advice to the more serious amateur, keeping them informed of the latest and forthcoming technological developments. the quest for color particularly “natural color” [3] was eagerly anticipated by most writers in these publications, stoking readers’ excitement with articles about what to expect: “do you want natural color motion-pictures? yes, you do! color, good color, is obtainable!” (s.n., photo era, 1929) some even recognized the role that the rapidly-growing amateur market had played in the development of the new color technologies: “… industry has found amateur markets a sufficient spur to evoke invention and evolution designed for amateurs alone.” (maxim, 1928) in contrast, there were detractors and doubters too, for reasons of both practicality and cost, but also aesthetics. some writers just did not consider color necessary for the amateur. for example, in photo era’s amateur column, herbert mckay, asserted that the amateur cinematographer did not need color, concluding, "let us be content to accept the monochromatic film [...] as our standard.” (mckay, 1926) others asserted that amateur filmmakers were very much the pioneers and that they had the power to drive the market and even influence the professional industry. for example, carl oswald was confident that, “… the efforts of the amateur […] lead to advances which the commercial organizations cannot afford to anticipate by the establishment of experimental laboratories.” (oswald, 1928) 2. a chronology of color in early amateur moviemaking the earliest (pre-1935) methods for producing color in amateur motion picture film were all additive processes, wherein colors in the image are created by the addition of colored light sources, such as filters or dyes, located either on the film stock itself or attached to the camera and/or projector. these early amateur motion picture color processes can be categorized into four broad groups (fig. 1): 1. the application of color to the film or projected image (either applied directly to the film or through filters on the projector), 2. lenticular processes, 3. rotating, alternating filter mechanisms used to produce natural color, and 4. dufaycolor’s unique réseau. the dates in the table indicate the introduction of a process and its approximate obsolescence. fig. 1. a chronology of motion picture color processes available to the amateur filmmaker, pre-1935 2.1. direct application of color to the film or projected image fig. 2. advertisements and an article in amateur movie publications. special cinema coloring outfit ad, movie makers, 1928, p. 476; tinting and toning 16mm films, william stull, american cinematographer, 1933, p. 18; automatic colorator ad, movie makers, 1927, p. 65 several techniques were available to the amateur who wanted to introduce color to the image, either directly to the film or to the projected image through colored filters attached to the projector. these techniques allowed the amateur to use color to interpret a subject or evoke a mood. for example, red for fire or danger, blue for a seascape or night scene. to apply color directly to the film, filmmakers could handpaint dyes onto the film, either covering the whole frame with one color or by intricately coloring specific parts of the image on each individual frame in an attempt to replicate natural color. advertisements in the press (fig. 2) show that hand-coloring equipment was available to the amateur filmmaker. many amateurs would have been aware of hand-coloring techniques from seeing films such as those from the edison and pathé studios. the technique of handcoloring individual frames was painstaking, immensely the start of the rainbow: possibilities of color motion photography for the amateur 49 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140106 time-consuming, and the results did not live up to the ultimate quest for “natural color”. nevertheless, professional hand-colorist, gustav brock, strongly advocated for – and practiced the use of hand-coloring in theatrical prints into the 1930s. (brock, 1930) he regarded it as an aesthetic choice, even when “natural color” was a possibility, brock enthused about hand-coloring’s appeal and how aesthetically effective it could be. while hand-coloring was an intricate and time-consuming process, tinting and toning was more easily achievable for the keen amateur. tinting was a technique used to color the highlights of the image by immersing the film in a dye bath, and provided an overall color to the whole, or sections, of the film. toning converted the black and white silver parts of the image to another metal, resulting in a different color depending on the metal. tinting and toning techniques were advertised in the early amateur movie makers press – both for home processing and as a lab service. the amateur press ran several articles detailing methods and techniques for the keen amateur movie maker to try at home. [4] as early as 1925, herbert mckay’s series on practical kinematography in photo era magazine (mckay, 1925) recognized the value of tinting and toning for amateur movie makers but he advised that it should be left for the labs to do. in contrast, later articles in the british amateur cine world and the american movie makers encouraged the more experienced amateur to experiment with tinting and toning techniques at home. (abbott, 1934; kerst, 1927) fig. 3. advertisement for color filter attachment for bell & howell filmo projectors (movie makers, january 1928, p41) color filter attachments which could be fixed in front of the film projector’s lens were a non-intrusive method of introducing color to the projected image. some projector models (for example, within the pathé 9.5mm and keystone 16mm series) had color filter attachments fitted as standard. filter attachments were advertised regularly in the amateur press throughout 1927-29. manufacturers included american cine products who made the automatic colorator, beckley and church, inc., makers of the koloray, and bell & howell’s filmo projector attachment with four color filter discs [5]. the automatic colorator attachment provided “15 different colors at your fingertips” which could be “individually or collectively interchanged simultaneously at the touch of a button”. (s.n., amateur movie makers, 1927) the koloray was a circular attachment that could be rotated to select a variety of colored filters, and also allowed for two-color combinations by aligning two of the filters in front of the projector lens simultaneously. this might be used, for example, in a landscape scene to achieve blue for the sky and green for the land. one koloray advertisement (s.n., movie makers, september 1928) carried a letter of recommendation from herbert mckay, who apparently embraced the use of color filters (and tinting/toning, see above) but also cautioned the amateur about the burgeoning natural color processes available to professionals, “color is a source of infinite pleasure—but only when presented properly” (mckay, 1926). manufacturers emphasized the devices’ ease of use and their ability to add color “without the necessity of tinting or toning” (s.n., movie makers, april 1928), as well as the benefit of “toning down the glaring white of the screen to save the over-exposed scenes which otherwise would be worthless.” (s.n., movie makers, april 1928) as with tinting and toning, the color filters provided emphasis to a scene or created a mood. the projectionist’s interaction and interpretation of the scenes also introduced an air of performance to the home movie experience.[6] 2.2. lenticular processes fig. 4. kodacolor box and kodacolor filter (chicago film archives); agfacolor filters (leitz photographica auction) the launch of kodacolor 16mm film in the united states in september 1928 was met with palpable joy by amateur cine league president hiram percy maxim, declaring that “kodacolor has made a dream come true” (maxim, 1928). in a lengthy and enthusiastic article recounting the the start of the rainbow: possibilities of color motion photography for the amateur 50 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140106 inaugural demonstration of kodacolor at george eastman house, maxim recounted an explanation of the lenticular technology employed in the kodacolor process, and reveled in the visual pleasure of the natural color that it produced, in particular, “the startling effect of seeing living, breathing flesh and blood”. maxim professed that he found the experience “very stirring”. (maxim, 1928) kodacolor’s technology was based on a process originally proposed by frenchman r. berthon in 1909, and further developed by a. keller-dorian. it required a special red, green, and blue striped filter (fig. 4) to be attached to the camera lens when shooting, and to the projector lens when projecting the film. the lenticular process utilized black and white reversal film, which had been embossed with miniscule lenticules (lenses) running lengthwise, covering the surface of the film’s base. maxim’s article quotes a fuller explanation given by dr c.e.k. mees, head of research department at eastman kodak, “the function of the lenses embossed on the film is to guide the rays of light falling upon each tiny area and lay them on the sensitive emulsion as three distinct impressions corresponding to the three filter areas, so that the three colors covering the lens are imaged behind each tiny cylindrical lens as three parallel vertical strips, because the tiny cylindrical lenses are parallel to the stripes of color on the filter.” (maxim, 1928) fig. 5 – diagram illustrating the lenticular process (coe, 1981) when the film was projected through the same three-color filter, a natural color image was achieved. this was “a novel and exciting capacity for the amateur cinematographer, one that put his or her craft ahead of even theatrical motion pictures, which still had limited color processes with which to work.” (gordon, 2013) in concluding his report of the inaugural demonstration, maxim fired up his readers with the promise of the new technology for amateurs: “… what is nothing short of epoch making, we amateurs are given the means by which we may render immortal our loved ones, for portraits made with kodacolor bring the living person directly before us.” (maxim, 1928) although the technology had its drawbacks, in particular, the need for additional accessories and the necessity for brighter lighting conditions, its ease of use and pleasing, natural colors meant that it was embraced by the keen amateurs who could afford it (the multipage kodacolor ad provides a detailed breakdown of costs, movie makers, august 1928), making it a relative commercial success. with this burgeoning success, kodak introduced additional accessories such as special projection screens to increase reflection and boost the loss of luminance due to the colored filter, and by the following year, rival manufacturer bell & howell was producing camera lenses and projectors equipped to shoot and project kodacolor (s.n., movie makers, may1929). due to its relatively widespread commercial success, several film archives in the usa have preserved examples of kodacolor. while there were reports of lenticular agfacolor 16mm film being demonstrated in germany and britain in 1931 and 1932 respectively (s.n., the international photographer, november 1931; s.n., the amateur photographer and cinematographer, 1932), and an extensive description of the principles behind the process in the journal of the society of motion picture engineers (weil, 1933), it is not known if lenticular agfacolor for amateur movie makers was ever manufactured for commercial sale [7]. the filter in fig. 4 was likely for a stills camera using lenticular film. 2.3. rotating, alternating color filters – natural color based on processes available to professional filmmakers such as kinemacolor and biocolour in the 1900s and 1910s, a number of attempts were made to replicate the principle of an alternating color filter for the amateur market. vitacolor was the most commercially successful of these. fig. 6 – vitacolor used the same principle as the earlier kinemacolor process, illustrated here (coote, 1993) invented by cinematographer, max b. du pont (not related to the family of chemical and film stock manufacturers), a the start of the rainbow: possibilities of color motion photography for the amateur 51 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140106 frenchman who emigrated to the usa in the early 1900s to work in the motion picture industry, and whose “desire to improve motion pictures with natural color came to him one day while examining some pathé hand-colored film” (anthony, 1928). the process, which he developed over 10 years, used 16mm [8] black and white negative stock, which was exposed in the camera through a rotating filter, alternating between red and green so that alternate frames were exposed through either the red or green filter. after processing, a positive print was made, which was then projected through a rotating, alternating red and green filter attached to the projector, producing a natural color image. (fig. 6). fig. 7. vitacolor advertisement (movie makers, may 1929, pp. 282-283) throughout the latter part of 1928, numerous demonstrations were presented across the usa, and vitacolor was launched onto the market the following year. articles in the amateur cine press described and praised the new technology. full page advertisements (fig. 7) sometimes double-page spread and illustrated appeared in the amateur press. as was common at the time, a woman modelled the camera in order to emphasize the technology’s ease of use. the ‘vitacolor girl’ – mary mabery featured heavily in its promotion. formerly “... a sennett girl […] from the university of california, where she was specializing in a course of athletics for a career of athletic instruction in high schools and universities” (s.n., 1927), she became the face of vitacolor’s print advertisements and featured in some of the demonstration films. as with the lenticular process, vitacolor’s colored filters reduced the amount of light reaching the film’s emulsion, so brighter lighting conditions were necessary. there was also an issue with “fringing” – the separation of the red and green projected images – particularly when the filmed subject was in motion. despite this, the process was wellreceived by those who attended the demonstration screenings, even by those who had previously been skeptical about color. natural color skeptic, herbert mckay heralded vitacolor to be superior to “old” kinemacolor, and declared, “every amateur owes it to himself to make films in natural color” (mckay, 1929) while there are no exact figures available, some amateurs--albeit wealthy amateurs who could afford the initial cost of the hardware over $2,500 in 2022’s money—did invest in the technology. the yale film archive holds some examples of vitacolor in its s.w. childs collection. in austria, several years after vitacolor was launched in the usa, ukrainian-born josef mroz, experimented with a similar process for 9.5mm film. comparable to friesegreene’s biocolour, the process exposed panchromatic black and white stock through a rotating, alternating green and red filter, then after processing, the film’s alternate frames were colored red and green by the application of dyes directly onto the film. mroz probably used a machine to apply the color to the film but the coverage was inconsistent, resulting in dense patches of color in some areas of the frame and thinner in other areas. because the color was applied directly to the film, there was no need for a rotating filter on the projector. the process was never made commercially available (zingl, 2018). fig. 8. morgana color/bell & howell advertisement (movie makers, july 1932, p. 285); color alternation chart (smpe journal, 1933, pp. 403-412) the morgana color [9] process refined the alternating red and green filter technique by attempting to eliminate excessive flicker and fringing during projection. this was achieved by a complex projection mechanism devised by lady juliet williams of pontyclun, south wales [10] a politician and advocate for social reform, with a strong interest in motion pictures. she was inspired to develop a practical color process after spending time on a film set in 1924 with her mother, the author, screenwriter, director/producer elinor glyn. over several years, lady the start of the rainbow: possibilities of color motion photography for the amateur 52 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140106 williams worked with co-inventor george short to create a mechanism that advanced the film two successive frames forward and one backward and thus (reportedly) eliminated flicker. according to bell & howell employee joseph dubray’s detailed article in the journal of the society of motion picture engineers, this was achieved by a quasi-increased film speed: “… although the film is running at a linear speed of 24 frames per second, 72 frames are alternating at the aperture during the same length of time, each picture frame being projected three times on the screen.” (dubray, 1932, p. 410) the diagram in fig. 8 illustrates this. fig. 9. morgana color filter wheel on the projector (dubray, 1933) in december 1931, the morgana color process was backed by bell & howell, and in 1932 they began promoting it for use with their 16mm filmo cameras and projectors. in the march 1933 issue of the international photographer a short article describes a 350ft film made by a bell & howell employee (dubray) of the 1933 tournament of roses, pasadena, usa (s.n., 1933). it is reported that the film was shown to an audience of 300 as well as at a private screening for the parade’s grand marshal, mary pickford, and douglas fairbanks. later that year, the amateur section of american cinematographer reported that comte de janze of paris would be experimenting with morgana color on his forthcoming game-shooting trip to africa. (s.n., american cinematographer, 1933). despite these references to morgana color films being made, and bell & howell’s promotion of the process, no extant films or equipment are known to exist (with the exception of a few sample frames in the theisen film frame collection at the seaver center for western history, los angeles). with the onset of the great depression in the usa and other, more practical and affordable color processes on the horizon, there is little evidence that the equipment was ever sold commercially. simon brown notes that, “the registrar was informed to dissolve the [morgana color] company in february 1937 and it was noted at this point that the morgana patents had been allowed to lapse and that the agreement will bell and howell was therefore valueless.” (brown, 2012, p.277) 2.4. dufaycolor réseau fig. 10. dufaycolor réseau (the dufaycolor process, 1935); dufaycolor schematic (spencer, 1948) launched in the united kingdom in september 1934, dufaycolor 16mm was the first motion picture color process available to amateurs that did not require additional accessories to produce a color image. based on the ‘screen plate’ principle, and drastically refined from louis dufay's original process for stills photography in the early 1900s, the complex mechanical manufacturing process added a minute regular pattern of red, green, and blue dyes the réseau to the base of a black and white reversal film. the film was exposed in the camera with the its base facing the subject so that light passed through the réseau’s colored dyes before exposing the black and white emulsion. after processing, the film was projected with the emulsion facing the projection screen, so that light from the projector lamp passed through the colored base first and created a natural color image on the screen. when viewed at an optimal distance, the pattern of the réseau was barely discernible. fig. 11 – advertisements for dufaycolor movie film (amateur cine world, sept 1934, p. 156; movie makers, june 1935, p. 232) karl a. barleben’s article in the international photographer in april 1935 excitedly pronounced that, “dufaycolor [sic] is here with a bang!” (barleben, 1935) the start of the rainbow: possibilities of color motion photography for the amateur 53 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140106 he observed that the numerous attempts to achieve natural color over the last few years had “not been a particularly successful venture, technically or financially. […] at the present time, there exists a most practical and worthy natural process – the dufay color [sic] process.” its benefits he noted, were that, “it has speed galore, requires no special adjustments or accessories, and reproduces color in a manner which is nothing short of amazing, considering that it is a one-film process.” (barleben, 1935) because of its ease of use and, contrary to barleben’s claim of “speed galore”, the brighter lighting conditions needed for optimum exposure, dufaycolor enjoyed reasonable commercial success up to the 1950s (in stills photography, too). dufaycolor’s usa launch in spring/summer 1935, however, coincided with the introduction of kodachrome 16mm film, which offered the amateur even greater ease of use (although not accurate natural color for the first three years). nevertheless, dufaycolor introduced 9.5mm reels and cartridges in 1937, and the process remained on the amateur market until around 1950. the possibility of producing 8mm dufaycolor was considered by its manufacturers (hercock, 1979), but apparently never realized, possibly because the réseau would be too visible and intrusive. there is mention of 8mm dufaycolor in some amateur movie magazines, and a few sample frames exist at the theisen film frame collection at the seaver center for western history, los angeles, but otherwise it was not known to have been commercially produced. however, a reel of poorly-slit 8mm dufaycolor was discovered a few years ago by the author of this paper, and has been donated to the university of southern california’s hugh m. hefner moving image archive. the history and provenance of this reel is yet to be determined. examples of 16mm and 9.5mm dufaycolor can be found in many regional film archives, particularly in the uk. 3. conclusion in 1933, writing in the journal of the society of motion picture engineers, f. weil (weil, 1933) outlined what he believed to be the principal requirements to make motion pictures in natural colors practically and technically successful: 1. the photographic manipulation and apparatus must be simple 2. the process must provide sufficient color saturation and resolution; that is, the color elements must be small enough to be unobjectionable 3. it must be possible to make prints from an original exposure 4. the process must make efficient use of the available light, both in making camera exposures and in projecting the pictures on the screen these requirements echoed the predominant prescriptive approach of the majority of those writing about and making photographs and movies at the time. with the arrival of kodachrome in 1935 and its ability to fulfill the above criteria (at least post-1938) the path was set for subtractive processes to dominate the markets, both amateur and professional. but while the impracticalities of accessories and slow film speed, as well as poor costeffectiveness, meant that early additive color processes were short-lived and achieved relatively low commercial success, they should not be dismissed because of their inherent ‘flaws’ and relative lack of success. instead, their inventors’ ingenuity and each process’s unique characteristics and aesthetic qualities should be considered worthy of our appreciation and duly celebrated. 4. conflict of interest declaration the author declares that no actual or potential conflict of interest exists including financial, personal, or other relationships with other people or organizations within three years of beginning the submitted work that could inappropriately influence, or be perceived to influence, their work or objectivity. 5. funding source declaration no funding agencies in the public, commercial, or nonprofit sectors provided funding for this research. 6. short biography of the author(s) louisa trott has worked with amateur film collections at regional and national film archives in the uk and usa. she holds an ma in film archiving from the university of east anglia, and is co-founder of the tennessee archive of moving image and sound. she is currently liaison librarian for cinema studies and theatre at the university of tennessee, knoxville. notes [1] the title of this paper is adapted from carl oswald’s article, “the end of the rainbow – possibilities of color motion photography for the amateur” (oswald, 1928) in which he considers the feasibility of color motion pictures for the amateur. published in january 1928, marginally pre-dating the introduction of lenticular kodacolor, the article weighs the eager anticipation of color for the amateur filmmaker against the practical considerations of cost and the limitations of technology. oswald was an authority on photographic processes and was a regular contributor to the start of the rainbow: possibilities of color motion photography for the amateur 54 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140106 movie makers magazine. for a brief biography of oswald, see movie makers, june 1928, page 422. [2] réseau is the french word for “grid” or “network”, and refers to the “screen” formed by the three colored dyes applied to the film’s base. [3] “natural color” referred to a photographic image whose colors closely replicated the original scene, in contrast to the color-block effects of tinting or hand-coloring. [4] a few examples of this technique can be found in the amateur movie database (www.amateurcinema.org/), but generally, examples of handcoloring and tinting/toning in amateur films seem to be fairly rare. [5] the author has yet to locate any extant examples of the automatic colorator, the koloray, or the bell & howell filter attachments. [6] the author has been unable to locate any examples of these filter attachments in museums, archives, or private collections, but at the northeast historic film symposium in 2019, the effect was replicated in a presentation, and proved to be quite satisfying producing an audible gasp from the audience in spite of the primitive, low-tech process. [7] the name agfacolor was later used for other color processes made by agfa. the timeline of historical film colors has some sample frames of lenticular agfacolor. [8] in addition to 16mm, vitacolor was originally trialed in 35mm for the professional market, but du pont decided to focus on the amateur market alone. [9] the author has not yet found an explanation for why the name morgana color was chosen. an informed guess might be that the name is a reference to the county of glamorgan, where lady williams lived, and/or possibly a reference to the character of arthurian legend, morgan le fay (aka morgana), whose origins lie in welsh/celtic mythology. [10] pontyclun, south wales (pronounced pont-uh-clean) – in recent literature about morgana color, the name of this town has sometimes been misspelled as pontyclud, probably originating from a typographical error in brian coe's history of movie photography (1981). also originating from south wales, the author of this paper has a personal interest in the history of morgana color and its inventor, and is currently working on a more detailed biographical piece about lady williams. references abbott, h. (1934) ‘this is how to stain and tone your films’, amateur cine world, november, pp. 353-54 anthony, e. (1928) ‘vitacolor movies: reporting a new color process for the amateur’, movie makers, december, pp. 771-72; 826-27 barleben, k. (1935) notes on color photography: dufaycolor is here to stay. the international photographer. april, p.14 brock, g. (1933) ‘artist explains hand color role’, motion picture news, march 1, p. 62 brown, s. (2012) color films in britain. the negotiation of innovation 1900-55. (ed. sarah street) basingstoke: palgrave macmillan. p. 277 coe, b. (1978) colour photography: the first hundred years 1840-1940. london: ash and grant coe, b. (1981) the history of movie photography. westfield, new york: eastview editions. p. 119 coote, j. (1993) the illustrated history of colour photography. surbiton: fountain press dubray, j. (1933) ‘the morgana color process’, journal of the society of motion picture engineers, november, pp. 403-412 dufaycolor process, the. (1935) ilford, london: ilford limited eastman kodak company (1928) ‘the eastman kodak company presents kodacolor’, movie makers, august, between pp. 522-23 gordon, m. (2013) ‘lenticular spectacles: kodacolor’s fit in the amateur arsenal’, film history, pp. 36-61 hercock, r. and jones, g. (1979) silver by the ton: the history of ilford, ltd 1879-1979. maidenhead: mcgraw-hill, p. 65 kerts, w. (1927) ‘tinting data’, movie makers, september, p. 16 maxim, h. (1928) ‘color comes to the amateur’, movie makers, september, pp. 567-71; 614-17 mckay, h. (1925) ‘the laboratory’, photo-era, april 4, pp. 207-11 mckay, h. (1926) ‘the amateur kinematographer’, photo era, 5 may, p. 285 mckay, h. (1929) ‘vitacolor’, photo era, 4 april, p. 228 oswald, c. (1928) ‘the end of the rainbow – possibilities of color motion photography for the amateur’, movie makers, january, pp.15; 56 s.n. (1927) ‘catalina channel classic is sennett comedy background’, january 29, p.357 s.n. (1927) ‘your motion pictures in color’, amateur movie makers, december, p. 65 s.n. (1928) ‘get stunning color effects’, movie makers, april, p. 269 s.n. (1928) ‘another letter about koloray’, movie makers, september, p. 606 s.n. (1929) ‘kodacolor-equipped filmo projector’, movie makers, may, p. 315 s.n. (1929) ‘natural color – promise or threat?’, photo era, 3 september, p. 171 s.n. (1931) ‘films and film processing’, the international photographer, november, p. 36 s.n. (1932) ‘the agfa 16-mm colour film’, the amateur photographer and cinematographer, september 21, p. 274 s.n. (1933) ‘in morgana color’, the international photographer, march, p.39 s.n. (1933) ‘compte de janze doing color picture’, american cinematographer, may, p. 28 spencer, d. (1948) colour photography in practice. new york: pitman press stull, w. (1933) ‘tinting and toning 16mm films’, american cinematographer, may, pp. 18; 32 weil, f. (1933) ‘the optical photographic principles of the agfacolor process’, journal of the society of motion picture engineers, april, pp. 301-08 zingl, s. (2018) ‘91/2-mm barni film je tu!’, kino!, may, retrieved 2019 https://e-kino.si/clanki/9%c2%bd-mm-barvni-film-je-tu-barvna-senzacijamrozovega-farbenfilma/ microsoft word 150107 48 color culture and science journal vol. 15 (1) doi: 10.23738/ccsj.150107 an analysis of chromatic and luminous environment of healthcare establishment. estelle guerry lara-seppia ea 4154 (ut2j), université de toulouse, france. corresponding author: estelle guerry (eguerry.contact@gmail.com) abstract this paper presents a protocol for analyzing the color and light parameters of a sanitary environment, based on the study of the chromatic and luminous atmospheres of the sanatorium paimio’s main building, designed by the architect aalvar alto. thanks to this protocol, it is a question of identifying and deciphering the sanitary plans of the architect. for this, i based my exploratory work on the development of a chromatic and luminous “identity card” which lists the different colors and lighting modes used. the study is divided into three phases: color observation, light observation and observation of interactive movements. this study highlights the work carried out by the architect on the behavior of chromatic atmospheres under different light and their influence on human reactions and needs, ensuring the most favorable conditions of vision and rest for the patients who stayed at the within the sanatorium thanks to the combination of the fields of physics, aesthetics, physiology and psychology. keywords care, color-design, comfort, hospitalization, interdisciplinarity, lighting, well-being. received 30/03/22; revised 06/10/22; accepted 30/12/22 an analysis of chromatic and luminous environment of healthcare establishment. 49 color culture and science journal vol. 15 (1) doi: 10.23738/ccsj.150107 1. introduction finnish architect alvar aalto designed the paimio sanatorium (1929-1933) for welcomed patients from all over the world suffering from tuberculosis. this facility allowed patients to enjoy complete rest in optimal conditions. the architect considered the following situation: a patient lying in bed, forced to spend most of his time there. his primary objective was that the technique serve the needs, sensitivity and emotional demands of patients (kim, 2009). as convalescence can last several years, the architect designed an environment conducive to community spirit and social cohesion between patients and caregivers through the design of equipment and spaces accessible to all. moreover, in a functional [1] and biodynamic [2] purpose, he designed an architectural program that makes the built environment itself active during the convalescence of patients. so, the exposure of each wing of the building made it possible to respond to “the deep needs of each person in accordance with nature” (menin & samuel 2004, p.57). for each of its architectures, aalto has relied on color, light, space and materials to design atmospheres conducive to the psychological and physical needs of users (arnkil, 2018). color was therefore one of the major elements in the design of this building, used as a therapeutic principle. the architect designed the color palette of the paimio sanatorium in collaboration with the artist eino kauria, responsible for coordinating the color scheme and directing the painting work (eylers et al., 2016). thanks to the use of various types of psycho-sociological effects, the architect associated the design of atmospheres with the associations of ideas, both subjective and objective, conveyed by the representations associated with the colors. they decided to rely on western codes, identifiable and recognized by the majority of patients. but colors also played a physiological role that did not only depend on these cultural representations. inspired by the principle of chromotherapy, according to which colors can have a curative action, the polychromy of the sanatorium aimed to relieve the ailments of patients. the choice of wavelengths (kent, 1947) (déribéré, 1968) was inspired by work involving the physiotherapeutic principle, today called phototherapy, according to experiments carried out between the 19th and 20th centuries, particularly for the treatment of measles (chatinière, 1900) or smallpox (rehns, 1904). for example, newborn jaundice is treated by exposure to blue light. this treatment is based on exposing to visible monochromatic blue light between 390 and 495 nm. the wavelength most used today in phototherapy is 450 nm. it effectively reduces the level of bilirubin in the baby's blood. (ennever, mcdonagh and speck, 1983) (shirzadfar, 2019). 2. material and method the following case study therefore aims to define the chromatic and luminous properties of the paimio sanatorium’s main building (health establishment) to identify the architectural parameters influencing the recovery of patients. the study is divided into three phases of observations: 1/ color observation consists of identifying color samples of architectural elements (floors, walls, joinery, stair railings and balustrades). not having been able to personally experience this place, the study was conducted based on photographs and color board painted by kauria (riksman, 2016) and optical color matching [3], compared to the colors of the ncs color chart. a margin of error is therefore inevitable but deemed acceptable because the objective of the study is to translate a thought and not to develop a reproducible reference. the chromaticity values identified in this study can, reduced to their spectral property, present a difference of 1 to 2 nm with the original colors for colors ranging from blue to orange, and up to 6 nm for violet. and reds, values corresponding to the threshold of differentiation of hues in wavelength of the human eye (wright et al., 1934 cited in treméau, 2016). in addition, the photographs did not allow me to identify the nature (matte or glossy) of the paints used nor the reflection value of the paints used. the same work was carried out on the furniture (tables, chairs, lights). the main spaces are represented (outdoor environment, reception hall, dining room, meeting room, bedrooms, corridors, stairs) and reproduced in the form of a map [4] making it possible to identify the sociostyles used [5]. 2/ the light observation made it possible to identify the different artificial lighting modes used as well as the types of lighting, supplemented by the natural lighting methods. i was unable to collect the elements relating to the characterization of the light sources. only the different types of artificial lighting and natural light were observed. 3/ the observation of interactive movements (lassus, 2004) consists of observing all the chromatic variations, according to the principle of light reflection and their mutual influences on our perception. 3. results 3.1. phase 1 – color observation for the chromatic observation of the interior environment, i therefore rely, in addition to the photographic archives, on the finalized color scheme of the main building painted by eino kauria (fig. 1.), which can now be found in the collections of alvar aalto museum, jyväskylä, finland (riksman, 2016). an analysis of chromatic and luminous environment of healthcare establishment. 50 color culture and science journal vol. 15 (1) doi: 10.23738/ccsj.150107 fig. 1. color scheme of paimio sanatorium’s main building. is probably the original board produced by eino kauria. in parallel with the listing of the ncs colors present on board figure 1, i sought to identify the colors present in the photographs (fig. 2.) in order to then correlate them and obtain a representative referencing of the interior and exterior chromatic program and of the furniture (fig. 3.). fig. 2. photographic sample (interior and exterior environment) of the paimio sanatorium based on photographics archives of alvar aalto foundation. fig. 3. color measurements in ncs s based on photographic observation and kauria’s color scheme board. we observe a wide polychromy built around thirty-five shades (fig. 4). it is divided into four categories of color effects: warm, cool, neutral and achromatic colors. there is also a complementarity between certain colors of the furniture elements, between a blue-green and red, associated with a play of neutrals and punctuated by the use of darks. in addition, we observe a majority of warm colors and achromatic ones, representing almost a third of the colors (table 1). an analysis of chromatic and luminous environment of healthcare establishment. 51 color culture and science journal vol. 15 (1) doi: 10.23738/ccsj.150107 fig. 4. chromatic cartography of the sanatorium program. it represents the proportion of each color and their use. colors are classified according to their hue and achromatic ones according to their degree of lightness. table. 1. chromatic distribution according to hue and lightness degree according to the previous mapping. light colors [6] are mainly used and are the only ones used for warm colors [7]. these nuances are distributed between the exterior, interior environment and furniture elements. the colors used for the interior environment represent more than half of the shades used for this architectural program. so, we observe different families of atmosphere in interior spaces according to different color combinations. the development of chromatic combinations results in the design of combinations that respond to the collective imagination. relative to specific atmospheres, this schematization is representative of the color universes previously established by the sociostyles. these combinations put into action the qualities of each color in order to transcribe a particular effect. they confer on the subject who benefits from them an identity character which must be recognizable by the user. a chromatic combination thus inscribes this subject in its time and the use that is made of it. it is defined in terms of chromatic typologies (dominant and tonic) and proportions. the dominants result in light, pastel, neutral, natural tones; the tonics are saturated, lively, dark tones of collective images, of representations conveyed according to the associations. the different combinations observed on the paimio program (fig. 5.) are as follows: 1/ natural (similar composition of warm colors and shades), 2/ dynamic (strong contrasts and dominant colors warm), 3/ modern (cold colours, strong contrasts), 4/ relaxed (complementary to contrasting colours, neutrals associated with a tonic), 5/ romantic (neutrals associated with a tonic). fig. 5. set of combinations identified according to families of atmospheres previously observed. warm cool neutral achromatic exterior light 6% 3% 2% 6% dark 3% interior light 19% 5% 17% 19% dark 1% 2% 3% furniture light 5% 2% 3% dark 2% 2% préhension et qualification d’un environnement chromatique et lumineux. etude de cas – sanatorium païmio, aalvar alto 52 color culture and science journal vol. 15 (1) doi: 10.23738/ccsj.150107 3.2. phase 2 – light observation there are two types of dominant openings intended to capture natural light: the zenithal and lateral opening. on the facades, there are window strips and large openings completed by a configuration of multiple leaves. we also observe frames with small footprints, except for large openings, as well as openings in the roof. opening lamp lighting bedroom casement window wall lamp, portable lamp. task lighting, mood lighting. common area skylight, window banner, casement window, glass facade. portable lamp, hanging lamp. passage area wall lamp, hanging lamp, recessed lamp. general lighting, mood lighting. dining room glass facade. hanging lamp. table. 2. directory of openings, lighting and type of artificial lighting according to the needs of use. regarding artificial lighting, there are different types of lighting allowing the production of general lighting (recessed and suspended luminaires), ambient (wall and suspended luminaires) and task lighting (localized extra light thanks to free-standing luminaires and portable lamps). 3.3. phase 3 – observation of interactive movements we observe variations in the perception of colors according to four modalities: reflection of exterior elements (fig. 6.), interaction with furniture, between two opposite walls, one of which is white, and between two different opposite walls (fig. 7.). fig. 6. chromatic variations resulting from the reflection of exterior elements. fig. 7. directory of the different chromatic variations resulting from the influence of light reflection on the built environment and furniture. external element reflection relates to the effect of color reflection from blinds when deployed. the blinds, in bluegreen and orange colors, slide towards warmer tones. this shift is also taking place on the paintings and the interior furniture. blue becomes green, neutrals become blue and pink-orange, dulls slip into warm pastels. the interaction with the furniture leads to the observation of many nuances. it is induced by the shadows cast by the furniture depending on the reflection factor of the floors and/or walls. if the chromatic dominant remains present, we observe a shift towards lighter or darker shades and going as far as a neutralization of the original color but without distortion of its tone. only saturation and lightness are impacted. regarding the interaction between two opposite walls, one of which is white, we can observe the lightening of the original color, to tend towards a neutralization of it. conversely, taking physical distance leads to a clouded perception of this tone. finally, the interaction between two different opposite walls leads to the observation of a game of chromatic complementarity. in the case of the projection of blue on brown, the complementarity of these two colors calls on brown to become dominant and to cancel the projected tonality. only the nuances of this dominant are perceptible to us, from the clearest to the most flattened, from the most saturated to the most neutral. on the contrary, for a projection of green on brown and pink on brown, leading to similar associations, the perception of green and pink are preserved. they only undergo a slight neutralization. we therefore observe a variation in their saturation, but also in their degree of lightness. préhension et qualification d’un environnement chromatique et lumineux. etude de cas – sanatorium païmio, aalvar alto 53 color culture and science journal vol. 15 (1) doi: 10.23738/ccsj.150107 4. discussion the chromatic combinations and lighting devices that we have previously observed can reflect the architect's desire to generate a harmonious chromatic and luminous scheme capable of generating a general feeling of wellbeing, comfort and serenity. the colors observed for the outdoor environment create a dynamic landscape thanks to the use of complementary colors that punctuate the white architecture. the major use of achromatic (white) generates a strong visual imprint. we can assume that the architect wanted to refer to hygienist representations [8], thus echoing the care provided in the establishment. the neutrals may have been used to attenuate the signal effect of the complements without canceling their function as spatial markers and uses. but the architect made the choice of an assumed polychromy, thus generating multiple atmospheres. it echoes the work of harry sherman on visual ergonomics. it was strongly impacted by the omnipresence of whiteness, artificial lighting creating many dazzling situations. the coloring of the environment then becomes a solution to counter this glare (sherman, 1914). the use of cold colors, minority and applied to the rooms, allowed him to create a peaceful atmosphere, calm and conducive to rest. on the contrary, warm colors and neutrals refer to comfortable and warm living spaces. yellow, mainly used in the entrance hall and meeting areas, could have been used for its soothing properties on nervousness (assuming the nervousness of patients arriving in this establishment). as for the achromatic ones, they offer breathing spaces in a punctuated and structured atmosphere around the color. the "broken complementary colors” [9] make it possible to neutralize the natural force of the combination of complements in favor of a light dynamic because "in the case of simultaneous perception […] a tone turns towards the complement of the opposite tone" (dumond , 1957). on the contrary, the “discordant harmony” [10] accentuates the signal effect and makes it possible to underline the spatial landmarks. beyond these methods of association, polychromy also makes it possible to generate various universes, according to the use lent to the spaces, recalling the systems of sociostyles (kobayashi, 1992) anchored in the collective imagination, according to the needs conveyed by the actions carried out in the areas concerned. the natural atmosphere induces a comforting image and an impression of serenity conducive to reassuring users, especially when entering the premises, while waiting to take exams or receive their care. the modern atmospheres, inducing an impersonal image, emphasize the functional character of the spaces. the relaxed atmospheres offer a welcoming and joyful image of these living spaces. the romantic atmosphere is considered ideal for rooms that must be calm, relaxing, conveying tenderness and benevolence. the dynamic atmospheres are also intended to be joyful and welcoming while encouraging action. but the sensitive dimension of color cannot dispense with its connection to light, which participates in particular in the evolution of visual perceptions. light, whether natural or artificial, can thus be designed to reinforce chromatic qualities but can also lead to their evolution by the reflection of colors on each other. these interactive movements (lassus, 2004) thus make the place active and tend to reveal multiple spaces over the course of the day. weather conditions play a major role in modifying the nature of the available natural light and generate variations in color perception. but above all, natural light improves the well-being and comfort of users, particularly in care practices (déoux et al., 2011). the different openings then have the role of filtering, guiding and distributing the light in order to maximize its capture. the combination of top and side openings then offers optimal autonomy in terms of natural lighting. this combination allows a significant light supply and this throughout the seasons. it also provides optimal exposure to the cyclical rhythm of natural light, known today for its benefits on the circadian rhythm, or biological process, of patients (zielinskadabkowska et al., 2017). but constrained by natural lighting conditions, it is necessary to use artificial lighting to compensate for natural light variations and thus produce quality lighting, free from the constraints of natural light. the use of different types of luminaire then corresponds to specific functionalities and makes it possible to meet different needs thanks in particular to the production of general, ambient and task lighting. general lighting is used to ensure the movement of users in the corridors and passageways, as well as the execution of common tasks in the common rooms. this type of lighting is characterized by a uniform, diffuse and homogeneous distribution of light thanks in particular to the use of large recessed and suspended luminaires offering direct lighting. ambient lighting, on the other hand, offers light dedicated to a momentary activity and qualifying a limited space. this type of lighting can be found in all types of interior spaces. the use of wall lights and suspended luminaires are thus conducive to the production of localized and diffuse lighting. the projection of light, thanks to indirect, semidirect, semi-indirect and mixed lighting, towards light surfaces thus ensures the diffusion of a soft and even light. finally, task lighting results in an increase in localized light thanks to mixed lighting, combined with general lighting, allowing the execution of tasks requiring a high level of focused and focused lighting. préhension et qualification d’un environnement chromatique et lumineux. etude de cas – sanatorium païmio, aalvar alto 54 color culture and science journal vol. 15 (1) doi: 10.23738/ccsj.150107 mostly seen in common areas and bedrooms, floor standing fixtures or portable lamps provide this directional light that can be adjusted as needed. thus, if welldesigned lighting is therefore defined by a sufficient quantity of light and the choice of a device that eliminates visual discomfort by glare, it is appropriate to choose and combine lighting modes adapted to the needs and thus make the secure interior space conducive to comfortable living. 5. conclusion we evolve daily in the midst of color and light, but apprehending a chromatic and luminous environment is above all receiving and interpreting visual information. they not only convey an aesthetic dimension; they are designed to meet challenges and a defined aim, to give the user a view. signs thought out by the designer and sent to the user, color and light will be received and interpreted. whatever the target, these signs must be in line with the images shared collectively, the local culture, the senses and the sensitivity of those who receive them. the designer then defines a color/light combination for its psychological effects (combination appreciated by the receiver, allowing him to invest his affect in the place and for it to provide him with some beneficial effects), and/or visual (choose a combination for its ability to attract the gaze or on the contrary repel it, to play with proportions and architectural organization as a visual landmark), influenced by a trend (so as to identify with what is happening elsewhere and now) or the collective cultural heritage (allowing to federate a community around signs that are common to them as an element of identification) (caumon, 2017). these reference frames of influence will thus make it possible to build an identifiable and identified chromatic and luminous environment, which can lead to affective reactions of pleasure or displeasure. but whether instinctive or conscious, the social role of lighting and color-design should be considered as a factor of wellbeing thanks to the combination of "physics, aesthetics, physiology and psychology” (déribéré, 1964). this study also questions the healing power of color and light. it is therefore a question of being concerned with the behavior of chromatic and luminous atmospheres and their mutual influences on human reactions, because using light and color is not only to illuminate and decorate, it is above all to ensure the conditions of vision and more particularly in this case study, conditions of rest and healing that are as favorable as possible to the patients. this therefore opens the way to additional studies to affirm or refute their curative effects on health, then considered as non-drug treatment. 6. conflict of interest declaration i indicate that no financial and personal interests have affected my objectivity as author. there are no potential conflicts. 7. funding source declaration this study is part of my thesis work, funded by a french university doctoral contract. this funding was not specifically dedicated to this study. this study did not receive specific funding. 8. short biography of the author estelle guerry – doctor in design-color and designlighting from the university of toulouse. its main scope of research applies to an interdisciplinary definition and application of the parameters of comfort and well-being of users presenting a vulnerability (ageing, handicap, illness, deficiency, etc.). it provides its expertise both in the research environment and in the socio-economic world. notes [1] functionalism is an architectural principle according to which the form of architecture is the expression of its use. the essence of modern architecture is linked to this principle. inspired by the teaching of violletle-duc, le corbusier will thus formulate the "five points of modern architecture" as the synthesis of a new modern architectural conception. these five points relate to the pilotis (disappearance of load-bearing walls in favor of concrete or steel pillars to support the structure), the roof terrace (principle of flat roof intended to accommodate terrace and vegetable garden), the free plan (disappearance of walls load-bearing allowing free modulation of space and being able to accommodate large glazed surfaces), the band window (horizontal windows crossing these non-load-bearing walls along the facades, offering uniform light and a view of the horizon) and the free facade (the load-bearing pillars being present inside the building, the facade becomes a thin and light skin, ensuring no more than an insulating role). the free plan as well as the window in bands will be two recurring points in the work of the finnish architect alvar aalto (jencks, 1973). [2] bioclimatic architecture is based on the exploitation of the properties of the site on which it is established. the climate, vegetation, sunshine, topography thus become key elements on which we can rely to create a comfortable environment for future users. bioclimatic architecture is also characterized by particular attention paid to respecting pre-existing landscape characteristics, trying to integrate as well as possible into the surrounding environment (tucci, 2021). [3] the practice of matching results in the collection of the different colors that make up the architectural program. this involves drawing up an inventory of the colors of the main architectural elements (floors, walls, joinery, stair railings and balustrades) and furniture (tables, chairs, light fixtures). the visual readings are operated by calibration using the ncs color chart. the ncs system, the natural color system, is a universal color repository, whose classification logic is based on the human perception of colors. this qualitative inventory is based on a photographic study. admittedly, photographs cannot be used for accurate color préhension et qualification d’un environnement chromatique et lumineux. etude de cas – sanatorium païmio, aalvar alto 55 color culture and science journal vol. 15 (1) doi: 10.23738/ccsj.150107 reproduction, but the conveniences of digital still allow for a representative study to be conducted when field trips are not possible. these chromatic witnesses, extracted from their context, are of major interest when grouping and reconstructing the information which is the basis of the synthesis result. [4] developing the maps makes it possible to produce a qualitative and quantitative restitution of the colors previously collected, in order to draw up a visual synthesis. this makes it possible in particular to count the tones and shades composing the chromatic set(s). analyzing the readings thus makes it possible to transpose them according to their recurrence. the colors of the roofs and the walls make up a first palette made up of the architectural chromatic dominants which represent the major part of the exterior built space. a second palette, the main palette, shows the colors used for the interior built space. it is the most consistent palette due to the large number of tones observed. finally, the last palette is made up of the tones of the details relating to the furniture. these palettes, represented in the form of maps, make intelligible the visual observation of the chromatic state of the site at an instant t. this synthesis thus constitutes a representative test of the quantitative ratios of the different tones. the samples are classified according to an ordered composition on two axes, each presenting a double reading inspired by the ncs system. a first axis will be readable from yellow to blue, the second from green to red. in addition, the double reading of these axes allows a reading of the degrees of lightness of the samples, the lightest at the ends and the darkest in the center. achromats have been excluded from the mapping to allow efficient reading of the shades involved. [5] applying the color image scale repository produced by shigenobu kobayashi, this system based on a principle of tri-chromatic composition makes it possible to categorize the colors observed according to the different universes that they can evoke. this classification of the color samples is carried out according to a purely qualitative criterion, the colors being considered in isolation, according to their representation(s). this sensitive approach leads to the production of chromatic combinations in respect of the interrelation between colors, according to the individual character of each of them, leading to the production of collective images, of representations conveyed according to the associations (kobayashi, 1992). [6] in ncs referencing, a so-called "light" color will have a black content index of less than 50, while so-called "dark" colors have an index equal to or greater than 50. (discover how the ncs system works). [7] in the west, color design is based on a principle of thermal color polarities, giving colors psychological and thermal properties. our culture separates colors according to the concept of warm tones (yellow, orange, red...) and those with cold sensations (blue, green...) by placing the "warm" and "cold" poles on a chromatic disc in front of orange and blue (silvestrini and fischer, 2011). [8] florence nightingale, a nurse in the middle of the 19th century, is undoubtedly the most significant person in the influence of the relationship between care practices in hospitals and color. its objective: to achieve an absolute degree of purity, both in terms of cleanliness and fittings. "the indisputable relationship between ventilation and cleanliness is demonstrated by this fact: a light-colored paper keeps clean" (nightingale, 1860). this will become a majority posture in the health sector, inducing that the idea of clarity leads to that of cleanliness, itself a premise of purity. and conversely, the ideal of purity engenders the notion of cleanliness, itself manifested by lightness, and concretely by whiteness. architectural design rules are emerging, such as the generalization of a suburban establishment to try to reduce the risk of contagion. whiteness becomes a quest, then considered as an antibacterial response. the discoloration of textiles by chlorine is born and becomes the disinfectant solution according to the health authorities in the hospital sectors. white then appears gradually, from changing rooms to earthenware, including paintings and furniture. thus, all aspects of an ornamental or decorative nature are prohibited. achromatic becomes the norm, a guarantee of cleanliness and health safety (fagot, 2020). [9] association of a color with the two tones located alongside its complementary (caumon, 2017). [10] association of a primary color with one of the adjacent colors of its complementary (caumon, 2017). licensing terms articles published in the “cultura e scienza del colore -color culture and science" journal are open access articles, distributed under the terms and conditions of the creative commons attribution license (cc by). you are free to share (copy and redistribute the material in any medium or format) and adapt (remix, transform, and build upon the material for any purpose, even commercially, under the following terms: you must give appropriate credit to authors, provide a link to the license, and indicate if changes were made. you may do so in any reasonable manner, but not in any way that suggests the licensor endorses you or your use, you may not apply legal terms or technological measures that legally restrict othersfrom doing anything the license permits. copyright: the authors keep the rights to further publish their contents where they want and can archive pre-print and post-print (submitted version and accepted version) and the published version of the pdf of their article with no embargo period. references arnkil, h. 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(2017) la conception lumière. appréhender le contexte, les enjeux et les acteurs. le moniteur. available at: https://depot.ceon.pl/handle/123456789/18480 (accessed: 4 january 2021. 112 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140114 about the influence of color perceived lightness on psychological functions alessandro bortolotti1,2, loreta cannito2,3, stefano anzani1,2, maurizio rossi4 and riccardo palumbo1,2 1department of neuroscience, imaging and clinical sciences, university gabriele d’annunzio chietipescara. alessandro.bortolotti@uinich.it, stefano.anzani@uinich.it, riccardo.palumbo@unich.it. 2center for advanced studies and technology (cast), university “g. d’annunzio” of chieti-pescara. 3department of psychological, health and territorial sciences, university gabriele d’annunzio chietipescara. loreta.cannito@unich.it 4department of design, politecnico di milano. maurizio.rossi@polimi.it. corresponding author: alessandro bortolotti (alessandro.bortolotti@uinich.it) abstract as human beings, we are continuously exposed to stimuli that modulate our psychological functioning and behavior, presumably through the influence exerted on our emotions. in literature, among others, the feature of color, mainly as related to the three attributes of hue, chroma, and lightness, represents one of the most explored topics. by the way, the multidisciplinary lens through which it has been investigated and the partial lack of methodological rigor make it difficult, thus far, to unify the research evidence while being able to disambiguate the single contribution of each color’s attribute. the current review aims to provide an overview of the most recent literature, focusing on evidence that highlights the role of the perceived lightness of color, in its function as well as aesthetic properties, in influencing psychological functions and behavior. practical implications and future directions in this research area are outlined. keywords color, lightness, psychology, context received 22/11/2021; revised 09/01/2022; accepted 07/04/2022 about the influence of color perceived lightness on psychological functions 113 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140114 1. introduction our world is full of stimuli that constantly bombard us, and we tend to give meaning to these stimuli. the stimulus that we perceive, most of all, and that involuntarily modifies our behavior is color. throughout history, different disciplines, with different research methodologies, have dealt with the study of color. through a series of theoretical and empirical works, they have created a general framework on the subject, as shown in other review works (elliot, 2015). the scientific literature presents several works on various aspects of color as a stimulus, such as the physics of color (fundamental properties of color), the physiology of color (processing color information), and the language of color (naming a certain color in different countries); these works have given an idea of how to study color in all its characteristics. however, even today, defining the term color, giving a definition that can be accepted by all the disciplines that study it, is a very difficult challenge. throughout history, color has been defined in a myriad of ways, and it is fair to say that a universal and definitive definition has yet to emerge (kuehni, 2005). in a psychological perspective, to fully define or understand the term color, it is important to distinguish two main characteristics that comprise it, the first being the physical nature of the stimulus as such, and the second being the response of the individual who encounters the color (hunt, 1978). in this case, color can be described as that perceptual phenomenon present in everyday life, capable of influencing our mood and our behavior according to the emotions it arouses. since the 2000s, there has been a boom in the scientific literature on the subject of color and psychology, with research in this field generally dealing with the relationship between color and human cognition in a broad sense. unfortunately, as other authors have pointed out, (elliot and maier, 2014) research in this field does not all have good methodological rigor. by methodological rigour we mean various aspects including, failure to control the physical characteristics of colour leads to a confusing design and results that are essentially impossible to interpret (valdez & mehrabian 1994). for example, if more than one colour attribute varies at the same time, it is not possible to determine whether a result obtained is due to the colour attribute of central interest or to one or more of the other colour attributes. in this review, the main aim is to shed light on the previous literature on colour and emotion, and in particular we will focus on the emotions that modulate cognitive performance through lightness. we will analyze recent theories and research regarding the possible relationship between emotions and the perceived lightness of color. given the vast number of theories on color, starting from aristotle, newton, and goethe, and also given the exponential growth of publications on the subject, we will focus only on the most recent and influential theories concerning the influence of color on emotion, utilizing the most objective works that have methodological rigor. up to this point, it is best to be patient and humbly acknowledge that the psychology of color is an extraordinarily complex area of inquiry (kuehni 2012) that is only beginning to manifest itself. the results of color research can be misleading, and because of the great interest of the various areas of research, it can be tempting to conclude before the scientific research is fully in place. there is considerable progress in research on color and psychological functioning, but much more theoretical and empirical work needs to be done before the full scope of this proposal can be identified and hopefully realized, perhaps yielding universal conclusions. so far, a limitation of previous research, which we will try to show in this literature review, is that most of the research conducted in this area, and related theories, has focused heavily on a single colour characteristic, hue. the purpose of this work is to show the importance of other colour characteristics, one of which is lightness. 2. background on color and emotions color exists only in the mind; that is, it is a highly subjective experience that creates strong individual differences (helm and tucker, 1962). this can be described as a perceptive, highly subjective response to light entering the eye directly from self-luminous light sources or, indirectly, from light reflected by illuminated objects. without going into too much detail, our visual system perceives the colours present in the colour spectrum thanks to the presence of three types of cones with different spectral sensitivity, they can be divided into three types, s cones (short), m cones (medium) and l cones (long). at this point, the definition of color that may be considered the most popular at present is the most recent offering provided by the cie (international commission on illumination): “color (perceived): characteristic of a visual perception that can be described by attributes of hue, lightness, and chroma”, and each of these attributes can influence psychological functioning (suk and irtel, 2010). in order to better understand this review work it is necessary to point out a distinction between lightness and brightness, which are often confused in the scientific literature. brightness is the attribute of a visual perception according to which an area appears to emit, or reflect, more or less light, while, lightness is the brightness of an area judged relative to the brightness of a similarly illuminated area that appears about the influence of color perceived lightness on psychological functions 114 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140114 to be white or highly transmitting. in summary, color perception provides us with a representation of the physical objects and lights in our three-dimensional environment (brindley, 1970; geisler, 1989). this process allows us a complete understanding of the space around us through different processes. the global process of "color perception" gives us a description of the physical properties of these objects and lights; a description of how information about these physical properties is transported by light to the eyes and stored by optics to form the retinal image; a description of how retinal photoreceptors respond to the retinal image; a description of how photoreceptor responses are transformed by visual processing into the way we see the world; and finally the emotional connection generated by the color-object interaction". each physical characteristic of the color taken individually has little value, but studying them individually allows you to better control the chosen variable, giving it the right importance. one of the characteristics of color that has been little considered up to now is the perceived lightness (which we will discuss in detail later). lightness is important as it allows us to optimally perceive an object; in this regard, it is right to introduce a neurological disorder (still unclear), in which sometimes it is the only component present. this pathology is known as "achromatopsia", literally means "not seeing colors", or severely reduced ability to discriminate between different colors shades (heywood and kentridge, 2003) but which allows, in different cases, to still perceive lightness (cole et al., 2003) "monochromatism" means "seeing shades of one color" (seeing the world in shades of grey). in this pathological condition, the fundamental importance of perceived lightness is highlighted and an in-depth study in this field will allow us to identify differences related to the “lightness” variable alone compared to the other physical components of the color. color has fascinated scholars for millennia (patricia, 1991; john, 1993). as a starting point for psychological theories associated with color, one could point to when the theory of color and psychological functioning has been present since goethe in 1810 wrote his “theory of colors” (johann wolfgang von goethe 1982), in which he linked color categories to emotional response (e.g., warmth, arousal). historical research on the topic has created at least general conceptual statements about color and psychological functioning, particularly with the general associations people have with colors and their corresponding influence on emotions, cognition, and behavior (frank and gilovich, 1988). as mentioned, color can have psychological and behavioral effects (elliot and maier, 2014), and it can also have purely aesthetic properties (schloss and palmer 2015). other studies have investigated the relationship between color and other more specific psychological variables, such as sexual attractiveness (pazda, elliot and greitemeyer, 2014), intellectual performance (shi, zhang and jiang, 2015), and food consumption (genschow, reutner and wänke, 2012; bruno et al., 2013). it is known that emotions can influence our cognitive functions, and these in turn are influenced by colour. in the last twenty years have seen an increase in research in the field of color on different cognitive functions, in fact, if we search in google scholar 'colour and cognitive functions', we get around 2 million scientific articles. one of the most investigated cognitive functions is the attentional process influenced by color. on selective attention, for example, it has been shown how red stimuli receive an attentional advantage (elliot and maier, 2007). research on color and alertness has shown that blue light increases subjective alertness and performance on attention-based tasks (chellappa et al., 2011). other cognitive functions have been investigated as studies on color and athletic performance have linked the use of red to improved performance and perceived performance in competitions and sporting activities (elliot and maier, 2012). empirical work on color and avoidance motivation has linked viewing red in performance contexts to increased caution and avoidance (elliot and maier, 2014). other studies, on the other hand, have investigated the relationship between memory-emotion modulated by color and how it affects performance in older adults (mammarella et al., 2016). as seen from the extensive reference literature, all effects of color undoubtedly depend on certain psychological conditions (or variables) that are independent of the stimulus but vary from individual to individual. these variables have been greatly underestimated until a few years ago (schloss, hawthorne-madell and palmer, 2015), variables such as the culture of belonging, sex, age, the emotional state of the individual, and the type of task (in the experimental case). these variables make the color-emotion interaction a process that cannot be underestimated and it is not universal. the awareness and realization that understanding these conditions will be an important marker of maturity for future work in this area (schwarz and singer, 2013; tracy and beall, 2014). these variables, hitherto underestimated, have created several methodological errors, creating results based on false expectations. it is therefore necessary to take individual variables more seriously, and give them their due importance. starting from the idea that color exists only in our minds, it is important to describe individual differences in color perception. in this regard, a recent psychological theory, the "color in context" theory (meier et al., 2012) is based on social learning and biology. this about the influence of color perceived lightness on psychological functions 115 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140114 new strand of research, with a more fully comprehensive view, for this theory all three of color properties may be important, at both the main effect and interaction levels, with regard to links between color and affect, cognition, and behavior, in addition, this theory places at the center a new variable that can influence psychological functioning, the context. some responses to color stimuli are presumed to be due solely to the repeated matching of colors to concepts, triggering particular experiences. others, however, are presumed to represent a biologically ingrained predisposition that is reinforced and shaped by social learning, as in a mechanism of natural selection (humphrey, 1976). the theory introduced, through this social learning process, color associations can be extended beyond natural bodily processes (e.g., blood flow modulations) to objects close to the body (e.g., clothing, accessories), making the theory applicable to various contexts, taking into account the variables listed above. as the name of the theory implies, it is believed that the physical and psychological context in which the color is perceived influences its meaning and, consequently the responses related to it. 3. color controversy a constant feature of this work points to important methodological problems that precluded rigorous testing and clear interpretation (o’connor, 2011). one such problem has been the inability to pay attention to scientific procedures including investigator blindness to the condition, identification and exclusion of colordeficient participants, and standardization of the duration of color presentation or exposure. one of the most common mistakes is the inability to specify and control color on a spectral level in manipulations. without this specification, it is impossible to know what precise combination of color properties has been studied and without such control it is inevitable to confuse focal and non-focal color properties (valdez and mehrabian, 1994). another problem is perhaps due to an optimistic view of one's research, as the effects of variables are inflated and given for universals (elliot and maier, 2014), color stimuli can also vary in terms of perceived typicality (the degree to which a color resembles a commonly seen representation of that color category). thus, more rigorous experimental work addresses both the multidimensionality and perceived typicality of color stimuli in manipulations; most research has not addressed either simultaneously. all of these methodological problems have greatly hindered (rigorous) scientific progress in this area. color control is typically improperly performed at the device level (rather than the spectral level), is impossible to implement (e.g., in web-based platform studies), or is ignored altogether. color control is certainly difficult, as it requires technical equipment to evaluate and present color, as well as the experience to use it. however, careful color control is essential if systematic scientific work in this area is to be conducted. the results of uncontrolled research can be informative in initial explorations of color hypotheses, but such work is inherently fraught with interpretive ambiguity that must be subsequently addressed. the process of color perception is not only a function of hue (is "color’s name", which represents a particular wavelength of visible light), lightness (represents the degree of reflected light), and chroma (refers to the intensity and purity of a hue), but also of factors such as viewing distance and angle, the amount and type of ambient light, and the presence of other colors in the immediate background and general surroundings (fairchild, 2015). in basic scientific research on color, these factors are carefully specified and controlled to establish standardized viewing conditions for participants. these factors have been largely ignored and have allowed for variation in research on color and psychological functioning, with unknown consequences. to date, most theories have focused on hue, one in particular, red, which is understandable given its importance in nature, body, and society (changizi, 2009). however, other hues also carry important associations that undoubtedly have effects on psychological functions such as green and blue (akers et al., 2012; labrecque and milne, 2012; mammarella et al., 2016). but lightness and chroma also undoubtedly have implications for psychological functioning (lee et al., 2013; kareklas, brunel and coulter, 2014); lightness has received some attention within conceptual metaphor theory (prado-león and rosales-cinco, 2011), but chroma has been almost entirely neglected, as has the problem of combinations of hue, lightness, and chroma. finally, it is also likely that many situational (bubl et al., 2010) and intrapersonal (fetterman, liu and robinson, 2015) factors influence color perception such as the concept of color preference (palmer and schloss, 2010). the complexity of color as a stimulus capable of creating psychological effects needs more attention and further scientific research in this regard, for while much has been done just as much remains unexplored. 4. the lightness effect the aim of this paper is to show the few studies on the subject of lightness, and to show how it may be of interest for future studies. on a physiological level, lightness of color influences the production and release about the influence of color perceived lightness on psychological functions 116 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140114 of hormones. color perception stimulates the neural portion of the optic pathway in the hypothalamic brain region and the pineal and pituitary glands, which control the entire endocrine system (mahnke, 1996). empirical work demonstrates the physiological effects of color in both animals and humans (bellizzi, crowley and hasty, 1983), with physiological effects such as heart rate, respiratory rate, blood pressure, muscle activation, blinking, palmar conductance, and brain waves. in this paragraph we will focus on the importance of one of the fundamental dimensions of color, lightness, which is just as important, if not more so, than hue (gorn et al., 1997; labrecque and milne, 2012). it has been known for many years that light directly influences physiology and increases arousal, but the effects of light can be nonvisible and influence behaviour by modifying the biological state of the individual (cajochen, 2007). in the field of neuropsychology, cognitive performance refers to the ability of the human mind to acquire, store and process information, to solve problems of any kind, from the simplest ones, such as the needs of daily life, to others decidedly more complex to study, such as the level of subjective vigilance and the level of alertness that involve the brain, and in particular the attentional process. in this regard, color lightness can influence all these factors by modulating the cognitive performance of individuals (rossi, 2019). there are non-visual effects of lightness that affect the human body through mechanisms other than melatonin regulation, through direct action on the human nervous system and with consequences that affect alertness level (or attentional process) (cajochen, 2007) mood (or emotion) (legates, fernandez and hattar, 2014) behavior (chellappa et al., 2011), and other human physiological parameters such as heart rate and body temperature. all this effects can affect the cognitive performance in every behavioural choice. in general, light and lightness, represent the core of the process of visual perception, through transduction, the process by which the energy (light) of environmental stimuli is converted into neural activity. leaving aside the difference between natural and artificial light, which have important differences between them (jazizadeh and wang, 2016), we will focus on the concept of lightness in general, without making this distinction. the effects of light on psychological components can be divided into several categories encompassing all human cognitive functions. 4.1. the lightness effect on emotion the human being is guided in his behavior by emotions and they are regulated by the context and experience (mesquita, 2007). the emotions triggered by the external environment change the internal state of the individual going to affect the regulation of body temperature, mainly due to endogenous phenomena such as sweating and vasodilation. the ability to perform this regulation depends on the body surface involved and on the temperature difference with the external environment. in this regard, a study has analysed research that relates the amount of light to thermoregulation and the subjective feeling of thermal comfort. in some cases, light with color shades that turn toward red induces a feeling of greater environmental warmth than light that turns toward blue (te kulve et al., 2016, 2017). however, the results of the latter type of research are sometimes contradictory because the context, mode of experimentation, and detection of results differ. in this perspective, psychological factors may also come into play, leading to different results in different social and cultural contexts. a non-pathological condition, winter depression or seasonal affective disorder (sad) is a disorder that affects people during the winter who are normally healthy during other seasons of the year (targum and rosenthal, 2008). the symptoms are those types of depression, such as lack of energy, tendency to sleep a lot, but also obesity, asthenia, insomnia, and difficulty in concentrating. it has also been observed that the same subjects in summer can show symptoms of intensified anxiety. for this reason, today this disease is no longer considered as an exclusive winter mood disorder, but as a disorder that can recur at different times of the year with different symptoms. studies have shown that the likelihood of contracting this disease is greater with increasing latitude and particularly in nordic countries, especially when exposed to solar radiation is lower (rosenthal et al., 1988). how color lightness relates to emotions is the subject of much psychological research, but the results are difficult to assess for practical use, the reasons for this are both technical and conceptual. on the technical side, color-emotion data have been collected using experimental methods that vary widely in precision and scope, as described below. to our knowledge, many of the studies on color and the relationship between color and emotion, to date have not used an objective method for studying color, not applying a correct description of color, without restrictions to specify the color (with a correct description of its characteristics) that best corresponds to a given emotional stimulus. these methodological problems make it very difficult to correctly study the physical characteristics of color such as lightness, which is a less studied characteristic than hue. if we wanted to list all the studies on the subject of colour associated with psychological characteristics, a review would not be sufficient, given the extensive literature on the subject. our aim, in fact, is to analyse the psychological functions about the influence of color perceived lightness on psychological functions 117 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140114 influenced by colour lightness. in this respect, it is important to emphasise the role of emotions in this interaction, as they are a ubiquitous aspect of human beings and which in turn influence the various human cognitive functions (dolan, 2002), as we shall see in detail. 4.2. the lightness effect on attention visual attention comprises a set of mechanisms that modulate sensory and cognitive processing to select the most behaviourally relevant stimuli for further limitedcapacity processing. which of the many retina-affecting stimuli will be selected is determined by both the task goals (top-down factors) (folk, remington and johnston, 1992) and the current stimulus processing (bottom-up factors) (itti and koch, 2000). how top-down and bottomup mechanisms interact in selection is still much debated (beck and kastner, 2009). the effects of light and lightness are visible in human behavior. these include behavioural changes throughout the day (circadian rhythm), in fact, the reaction times (in terms of behavioural response to any daily task) are generally longer in the early morning and decrease for the day only to increase again during the night and peak in the early morning (posner and petersen, 1990). these measures reflect other diurnal changes such as body temperature and cortisol secretion. this essentially modifies an attentional mechanism called “alertness” (petersen and posner, 2012); in this case there are at least two definitions of alertness, namely, the terms phasic and tonic alertness (posner and petersen, 1990). phasic alertness refers to the orientation response (sokolov, 1963) and tonic alertness will be used as a synonym for vigilance and sustained attention, these mechanisms can be influenced by colour lightness. for example, the psychophysiological and behavioural effects mediated by light stimulation, this by assessing differences in illumination (badia et al., 1991). the level of alertness, assessed with eeg through beta brain waves (14-30 hertz), showed a significant increase in the strong light condition, which also had the effect of decreasing drowsiness and increasing body temperature, going to modulate the alert attentional state. in another very relevant study (cajochen et al., 2005) the focus was on the chromatic component of light (blue light with a peak at 460 nm and yellow light at 550 nm). in the blue light condition, in addition to observing a reduction in melatonin, there was an increase in body temperature, heart rate, and level of alertness of the subjects involved. this did not occur with exposure to yellow light. similar results were also observed where participants were in a normal office setting (smolders, de kort and cluitmans, 2012). the results showed that with the brighter lighting the subjects had shorter reaction times, higher alertness level, and increased heart rate, especially towards the end of the hour of exposure to the stronger light. these results would demonstrate that even under normal daytime conditions, not in the dark and temporally away from rest periods, i.e., under physiological conditions other than those in which melatonin regulation comes into play, brighter light can improve feelings of alertness and vitality, as well as subjective performance and level of physiological activation. 4.3. the lightness effect on memory memory is now defined in psychology as the ability to encode, store, and retrieve information (squire, 2009); focusing on these processes, one research study investigated the effects of different wavelengths of light on brain waves associated with memory processes (okamoto and nakagawa, 2016). cortical activity was monitored using magnetoencephalography (meg) the experiment was conducted by exposing subjects for 30 minutes (during the day) to two different lighting conditions, green light (with a peak wavelength of 520 nm) and blue light (with a peak wavelength of 470 nm). the results showed that blue light increased cortical activity related to active maintenance of working memory. similar results were also observed in research in which, instead of monochromatic lights, they used two white lights 3,000 (warm light) and 5,000 k (cool light), noting that the 5,000 k light stimulates the central nervous system more (noguchi and sakaguchi, 1999). working memory in the human cognitive system is a part of memory, with a time-limited capacity, that supports the temporary storage of information available for brain processing (wynn and coolidge, 2011). this cognitive structure is important in reasoning and in guiding decision-making and behavioral processes. it should not be confused with short-term memory, which simply stores information temporarily but is not directly related to the brain's processing of information (cowan, 2009). working memory is a central theoretical concept in cognitive psychology, neuropsychology, and neuroscience in general. it is essential for learning activities and problemsolving. 4.4. the lightness effect on memory a popular way to study decision-making is undoubtedly the studies on consumers going so in the field of marketing. recent studies in this field are studies on cross-modal associations (two senses in one) (spence and parise, 2012) in this regard the lightness of the color is associated with characteristics such as hot-cold, or sad-happy (kaya and epps, 2004). the effects of the new correspondences between somatosensory and visual perceptions (warmth and color lightness) extend about the influence of color perceived lightness on psychological functions 118 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140114 from capturing visual attention to preference formation, as well as on how attitudes toward sensory experiences (i.e., positive reactions to sensory experiences) play a critical role in preference formation. the results showed the existence of cross modal correspondences between the sensation of warm and light colors (motoki et al., 2019). thermal environment and product color are important considerations when designing marketing strategies for many business settings. stores can usually control the ambient temperature using air conditioners, and light/dark colored products are displayed in such locations. recognition of the impact of sensory experiences in natural shopping environments has led to increased attention to the effects of such experiences on consumer behavior (krishna, cian and aydınoğlu, 2017). still, other studies, show how the color of a dark (versus light) product encourages higher durability ratings but lower ease-of-use ratings (e.g., a pc) (hagtvedt, 2020). both of these influences are related to the impact of color brightness on perceived weight: darker (compared to lighter) colors cause objects to appear heavier (sunaga, park, & spence, 2016). however, there is still little evidence in this area of study. 4.5. the lightness effect on sleep light and lightness affect the circadian rhythm by compromising sleep (rossi, 2019). many people suffer from sleep disorders, which can have different causes and different effects, even of a serious pathological nature, which hinder a healthy daily life both from a physiological and psychological point of view, interfering with emotional states and social relationships (vgontzas et al., 1999). the most well-known disorder is that of insomnia, which occurs when the individual is unable to fall asleep despite being tired and having an actual physiological need to sleep (lockley et al. 2008). the effects of insomnia also affect the quality of daily life, as affected individuals often have difficulty concentrating and learning, related to the malfunction of working memory, but also chronic fatigue and irritable mood. in general, the main discomforts, which occur in 40% of cases of people suffering from insomnia, are psychiatric disorders, particularly depression and anxiety (roth, 2007). another form of sleep disorder is nocturnal bruxism, which has very serious negative effects: erosion of the teeth down to the dentin, with an increased likelihood of fracture and of developing tooth decay and inflammation of the tongue. it can also induce headaches in the temporal areas, with possible ear discomfort caused by repeated nightly tension of the muscles acting on the jaw. this type of disorder results in restless sleep with nightmares, restless leg syndrome, increased heart rate, and various other types of disorders, including bruxism. it has been shown that approximately 86% of nocturnal bruxism episodes occur during restless sleep (lavigne et al., 2007). these are some of the most wellknown sleep disorders. in this field, some well-known research has shown that the use of bright light in the morning can help with typical sleep disturbances with subjects with an unbalanced circadian rhythm (figueiro and rea, 2016), while strong lighting (2,500 lx) after 8:00 pm can help reset the circadian rhythm and alleviate the typical disturbances (lack and wright, 2007). a review of the literature examined 21 research studies that investigated the use of light as a therapy for sleep disturbances, such disturbances being much more common in the elderly population. the elements that were considered were the amount of light, spectral power distribution (spd) of the light, time of exposure to light, duration of exposure, and direction of light (sloane et al. 2008). the positive effects of light on proper sleep timing and quality have been verified, several effects of light wavelengths have in this context have been highlighted (figueiro and rea, 2016). thus, excluding the need for excessively bright (annoying) lighting that is not applicable in the design reality, and instead of using normal comfortable lighting systems with white light and adequate content of short wavelengths (blue). there is now broad scientific consensus that light can be used as a therapy to improve sleep quality for all individuals (figueiro and overington, 2016). 5. conclusion the effects of light are varied, and are not limited only to the effects we have mentioned above; in fact, we can go on to say that the effects that light and lightness can have on learning environments have been a topic of research for some time. for example, three studies conducted in sweden (küller and lindsten, 1992) and the usa (heschong, wright and okura, 2002) have demonstrated the importance of the presence of windows and natural light on students' psychophysiological well-being and performance. two of them also demonstrated that these positive psychophysiological and performance effects are absent in windowless classrooms. we could go on describing other effects of light and lightness on cognitive performance, but while it is true that much has been done so far, it is also true that not enough has been done, due to the experimental limitations outlined above, with the lax way of conducting such research in the field being most to blame. moreover, the study of psychological effects related to color is a very hot topic, and one should approach it more cautiously without drawing hasty and universal conclusions. color is too complex a phenomenon or concept to "take lightly" its study, then associated with cognitive functions is an even more about the influence of color perceived lightness on psychological functions 119 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140114 difficult task because of the many variables involved. just think of the physical characteristics related to color and how difficult it can be to study them rigorously if you then have the "scientific presumption" to associate them to psychological characteristics without taking into account variables such as context and individual variables (just to mention a few) you fall into error. this work shows various limits of research in this field, it is hoped that this overview will let us think about the complexity of the stimulus and the importance of its correct decomposition into physical characteristics. perhaps by studying these characteristics individually, giving them all the right importance, it will be possible to obtain a more accurate result than those obtained so far; it is hoped that the focus of research will also shift to color characteristics such as lightness because, as shown, it matters a lot and its effects are visible. 6. future directions on the subject of the psychology of color (in all its parts) and its effect on emotions, there has been an exponential growth in the number of scientific publications in the last twenty years. being the topic of interest for several disciplines it is easy to think that the growth of publications will not stop in the recent future. technological advances have allowed other disciplines, such as neuroscience, psychophysics, visual cognition, and biology, to gain new insights into understanding the complexities of color perception using new populations and/or new methods such as neuroimaging (e.g. fmri, erp, meg), eye-tracking or modeling (computational or mathematical) (shevell and kingdom, 2008). the hope is that along with basic research, the results obtained from them can be made applicable. 7. conflict of interest declaration the authors declare that no conflict of interest, real or potential, including financial or personal links with other persons or organizations. 8. funding source declaration this research did not receive any specific grant from funding agencies in the public, commercial, or not-forprofit sectors. 9. short biography of the author(s) alessandro bortolotti psychologist and phd student in business and behavioral sciences at the university of chieti-pescara, where he studies neuromarketing and emotion using behavioral and neurophysiological methods. loreta cannito psychologist and psychotherapist in training, she obtained her doctorate in business and behavioral sciences at the university of chieti-pescara, where she deals with decision making and neuroeconomics. stefano anzani studied psychology and cognitive neuroscience. he's a phd student in business and behavioral sciences at the university of chieti-pescara, where he studies decision making using behavioral and neurophysiological methods. maurizio rossi msc, phd. at politecnico di milano he is professor of lighting design, director of the master in lighting design & led technology, director of the master in color design & technology, member of the phd in design. riccardo palumbo is professor of business and behavioural economics and neuromarketing at the department of neuroscience imaging and clinical sciences of the university of chieti-pescara. coordinator of the section of behavioural economics and neuroeconomics and the phd in business and behavioural sciences. co-founder and ceo of umana analytics. references akers, a. et al. 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(2011) ‘the implications of the working memory model for the evolution of modern cognition’, international journal of evolutionary biology, 2011, pp. 1–12. doi: 10.4061/2011/741357. 72 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130209b a test on color discrimination in complex scenes for a better comprehension of color blindness sof ia scipioni1, chiara andrea lombardi1, luca giuliani1, andrea mazzoni2, roberta marcucci2, alice plutino1 and alessandro rizzi1 1mips lab, computer science department, university of milan, milano, italy. sofia.scipioni@studenti.unimi.it, chiaraandrea.lombardi@studenti.unimi.it, luca.giuliani@studenti.unimi.it, alice.plutino@unimi.it, alessandro.rizzi@unimi.it 2istituto di medicina aerospaziale dell’aeronautica militare, roma, italy. mazzoniandrea@tiscali.it, roberta.marcucci@inwind.it corresponding author: alice plutino (alice.plutino@unimi.it) abstract today, in color vision and physiology, it is well known that the phenomenon of light transduction, operated by the retinal photoreceptors, cannot fully describe color perception. color perception, in fact, is a complex phenomenon which involves not only the signal transduction in the human retina, but also the signal elaboration made by the visual cortex. for this reason, it is fundamental to consider color perception as a result of the interaction of all the colors, shapes, shadows and lights in a scene, thus of the scene spatial arrangement. in this work, we present the results of a preliminary experiment to investigate chromatic perception phenomena in spatial contexts. to perform this test, we selected five famous paintings and we asked to color blind (cb) and non-color blind (ncb) people to complete three tasks. in the first and second test, the paintings presented a missing piece. here, the cb and ncb users had to select the correct paint missing piece among four patches with different chromatic values, at first isolated from the painting and then added in the artwork. in the third test the users had to identify the original artwork among a set of four images of the paint fully chromatically modified. thanks to this experiment it has been possible to have a first preliminary evaluation on the role of the spatial context in color discrimination, and it has been possible to analyze some of the main limits in color blindness actual models. keywords (color blindness, perception, visual system) received 11/08/2021; revised 01/10/2021; accepted 03/11/2021 mailto:sofia.scipioni@studenti.unimi.it mailto:chiaraandrea.lombardi@studenti.unimi.it mailto:luca.giuliani@studenti.unimi.it mailto:alice.plutino@unimi.it mailto:alessandro.rizzi@unimi.it mailto:mazzoniandrea@tiscali.it mailto:roberta.marcucci@inwind.it mailto:alice.plutino@unimi.it a test on color discrimination in complex scenes for a better comprehension of color blindness 73 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130209b 1. introduction the phenomenon of vision is a complex process, and it is still not completely understood despite years of studies and modelling (levin, et al., 2011). in the human eye, the retina is the sensible layer in which the nervous signals are generated in response to the visual stimuli coming from the surrounding environment. in the retina, the image of the visual world is f ocused and converted in electrical neural impulses, which are sent to the brain. the retina consists of several layers of neurons interconnected by synapses, and it is supported by an outer layer of pigmented epithelial cells. the primary light-sensing cells in the retina are the photo-receptor cells, which are of two types: rods and cones (davson, 1990). the external part of photoreceptors is composed by a layer containing the photopigment, a chemical substance that isomerizes when absorbs light (sharpe, et al., 1999). from this, the electric signal is generated as the f irst neural response to the visual stimuli, it is transmitted through the retina neural networks and it is processed by the visual cortex (curcio, et al., 1990). in this process of signal transduction and elaboration, the cones are the photoreceptors responsible for the photopic vision (e.g., daily vision) and f or the ability to see colors. there are three kinds of cones, and each type contains a dif ferent pigment that absorbs in different percentage the radiations of the visible spectrum, and each cone contains just one of those pigments. due to this, the cones can be classified in: cones l that cover the region of long and medium wavelengths with a maximum at 560 nm; cones m that absorb medium wavelengths with a maximum at 530 nm and cones s that absorb shot wavelength with a maximum at 420 nm (osterberg, 1935). color blindness (or color vision def iciency) is the decreased ability to see and distinguish colors. it is generally an inherited problem which af f ects the development of one or more type of cone cells. color blindness af fects mainly the male population (nathan, 1999) and correlates also with the ethnicity (brown & lindsey, 2004). in general, in individuals of northern european ancestry, the common f orm of red -green color blindness af fects the 8% of men and just the 0.5% of women (deeb, 2005). color blindness can be divided in many categories, among them we focused on dichromacy (i.e., the state of having just two types of cones) and anomalous trichromacy (i.e., the state of having one of the three types of cones which behaves like one of the other two). considering this subdivision, the kind of dichromacy or anomalous trichromacy can be classified depending on the absent (or anomalous) cone type in: protanopia (or protanomaly), deuteranopia (or deuteranomaly) and tritanopia (or tritanomaly). nowadays color blindness is studied and diagnosed mainly considering the retinal level of the visual path, because the problem originates f rom retinal anomalies. the many different color blindness tests, like the pseudoisochromatic plates (e.g., ishihara test), the nagel’s anomaloscope, the cad test, which have been f ound successful to diagnose this condition (evans, et al., 2021), are all based on the retinal modelling of the color stimulus. however, this approach only considers the point -wise color formation, without any spatial mechanism. from the f irst experiments carried out by von helmholtz in the 19th century and by land (land, 1959), (land & mccann, 1971), hubel (hubel, 1995) and wiesel (hubel & wiesel, 1998) in the 20th century, it become clear that describing color vision processes as a mere transduction at retinal level of a point-wise stimulus, is not sufficient (rizzi, 2021). thus, current state of the art suggests color perception in carried out both at retinal and cortical level, since spatial mechanisms are a f undamental part of the robustness of our visual system and are at the base of its capabilities of adapting to widely varying visual conditions (mccann & rizzi, 2011). in this context, a recent series of preliminary studies investigated the role of spatial mechanisms in cb people, to assess how much the spatial arrangement affects color perception (rizzi, et al., 2014, reprinted in vol. 13, july 2015.), (bonanomi, et al., 2017), (eschbach & nussbaum, 2021). this work f ollows the encouraging results evidenced by those recent studies and aims at preliminary analysis the roles of spatial arrangement and complex contexts in color perception of cb people. dif ferently f rom other experiments, in this work, we used as test images five paintings from different periods, and we aimed at assessing how much the scene spatial arrangement of non-natural scenes may affect the color vision in ncb and cb people, considering the presence of edges and gradients in the scene. thus, the main research question of this work is: gradients and edges in a scene, can help cb people in identifying colors? in this preliminary study we tested 30 subjects, of which 15 are color blind (cb), without f ocusing on the specific type of color def iciency. to this aim, in section 2 a description of the experimental setup will be reported, explaining the three dif ferent perceptual experiments. then, in in section 3 we report the main experimental results, which are broadly discussed in section 4. 2. experimental setup the experiment has been perf ormed on 30 subjects, 15 cb and 15 ncb. the sample of cb people was composed by 13 males and 2 f emales, and the sample of ncb subjects was composed by 4 males and 11 f emales. in a test on color discrimination in complex scenes for a better comprehension of color blindness 74 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130209b both groups the average age was of 23 years old. in order to test a wide set of subjects, the test has been performed remotely on different devices such as tablets, computers, or smartphones, and all the tests have been performed anonymously. the test has been conducted using the web application google form (google, 2021). bef ore the beginning of the test, we made a short survey asking to the participants for sex, age, and potential color blindness, we did not f ocus on the type of color blindness. in fact, since it was not possible to clinically diagnose the kind of color blindness which affected the users, in the initial form we just asked to the subjects if they know to be cb. in order to confirm the hypothesis of color blindness, in the analysis of the results, we also evaluated the number of correct and wrong answers given by the single subjects, to exclude false positives. for the experiment we selected the images of 5 paintings (see tab. 1). this decision has been made at first to have a set of images which could be pleasant for the users, but also controlled in terms of gamut mapping. in f act, the selected paintings have been studied to have unsaturated colors thus, to be reproducible without high gamut compression by different devices. furthermore, the use of paintings allowed us to use in the same test images very similar to the real world (picture a basket of fruit, picture b – the tempest and picture c the kiss), but also images with unnatural colors (picture d – arearea and picture e – sunf lowers). thanks to this we had the possibility to evaluate if the effect of gradients and edges on color vision is present independently by the image content, the saturation or the reliability of colors. in order to test the color discrimination of the users we altered the colors of the paintings simulating different kind of color blindness. the images have been daltonized using two different software coblis (colblindor, 2006-2021) and imagej (imagej, 2021). in fig. 1 is reported an example of ciexy chromaticity shift of 10 random pixels of picture e. since perf orming a remote test, it was not possible to assess and verify the type of color blindness of the users, we simulated the three main kinds of color deficiency to daltonize the images, to include all the possible color alterations. nevertheless this, in this study we do not aim at testing the efficiency of the color-blind simulation but at verif ying if a cb person can identify (thanks to gradients and edges) color shif ts in chromaticity regions which should be perceived as uniform f ollowing the actual cb theories. in this perceptual test we presented to the subject 4 images, the original, and 3 daltonized versions which simulate deuteranopia, protanopia and tritanopia. in order to assess the contribution of edges and gradients in the color perception we def ined three dif ferent setups which correspond to three different tests. in the f irst test, we presented to the subject a paint with a missing piece (see fig. 2) and the user had to select which piece is the right one, among a set of f our daltonized patches (colblindor, 2006-2021). in this f irst setup the missing piece must be chosen out of context. fig. 1. example chromaticity shift (ciexy) introduced on picture e. the filled red dot represents some pixels of the original painting, the black circles the pixels of the deuteranopia simulation, the blue asterisks the protanopia and the green stars the tritanopia. in the chromaticity diagram, are represented also the deuteranopia (solid lines), protanopia (dashed lines) and tritanopia (dotted lines) confusion lines (judd, 1945). a test on color discrimination in complex scenes for a better comprehension of color blindness 75 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130209b picture id description artwork picture a caravaggio, basket of fruit; c. 1596; oil on canvas; 46x64,5 cm. milan, pinacoteca ambrosiana picture b giorgione, the tempest; 1507-1510; oil on canvas; 82x73 cm. venice, gallerie dell’accademia picture c francesco hayez, the kiss; 1859; oil on canvas; 1,10x0,88 m. milan, pinacoteca di brera picture d paul gauguin, arearea; 1892; oil on canvas; 75x94 cm. paris, musée d’orsay picture e vincent van gogh, sunflowers; 1888; oil on canvas; 92,1x73 cm. london, national gallery tab. 1. picture id, description and image of the paintings used in the experiment. a test on color discrimination in complex scenes for a better comprehension of color blindness 76 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130209b then, in the second test we presented to the subject four versions of the original painting, completed with the patches presented bef ore (one original and three daltonized) (see fig. 3) and the subject had to choose which version of the painting is the correct one. in this second setup the missing piece must be chosen inside the image context. this setup has been made to create regular and irregular edges between the overall painting and the patches with altered colors. thanks to this test we aim at assessing if a wrong -colored image piece placed inside the original paint, is more distinguishable thanks to the presence of edges. in conclusion, as last test, the subject had to choose again which versions of the painting is the original one, choosing f rom f our version of the painting, one original and three f ully daltonized (imagej, 2021) (see fig. 4). in this case, the user had the possibility to compare the paintings under analysis with the previous versions. thus, in this last setup, we aim at assessing the ability of cb users to identify the overall color of the image, resorting to comparisons. for all the three tests composing the experiment, we gave to the subject the possibility to select one answer or the option n/d (non-defined), when he/she could not perceive any difference among the answers. in the appendix a are reported all the test images f or all the f ive analyzed paintings. 3. results in fig. 5, 6 and 7 are reported the answers given by the cb and ncb users, divided per painting. considering the results of the first test (fig. 5), the answers are strongly coherent in the f irst group (ncb) and presents a greater variability in the cb group. for the paintings b, c and d, the majority of the cb answers are exactly like the ncb’s, especially in the case of the paint d. for what concerns the paints a and e, just f ew cb answer correctly, thus there is an increase of variance. for the paintings a and e, 6 people out of 15 answered with n/d. also in the second test, the ncb provided quite uniform answers (fig. 6), but an increase of variance can be observed in the ncb and in the cb answers. some n/d answers have been reported by the ncb subjects for the paintings d and e, in particular the painting e is the one which presents the majority of n/d answers f or both cb and ncb. this painting is the one in which the cb subjects make more mistakes. considering the cb answers, the visualization of the daltonized patch inside the painting (test 2) made more difficult the identification of the correct patch, especially for the paint d, where in the f irst test the cb gave 12 correct answers. considering, now, the subdivision of the answers per users (fig. 8 and 9), this analysis could be useful to identify cb people in the ncb group, or vice versa. for what concerns the cb test group (see fig. 9), 5 subjects out of 15 made more than 4 errors and 11 subjects out of 15 gave n/d answers. a particular trend can be noted f or subject 7, who gave the biggest number of wrong answers (13) never choosing the n/d option and for subject 6, who gave 13 correct answers out of 15 (like some ncb people). these results will be discussed in the next section. fig. 3. second test example (picture a). fig. 2. first test example (picture a). fig. 4. third test example (picture a). a test on color discrimination in complex scenes for a better comprehension of color blindness 77 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130209b 4. discussion in general, the ncb test group had no problems in answering to the tests, even if some error (maximum value of 2) is present and some answers are n/d. in test 1, the users had to guess the right image missing piece, out of context. in this task, f or picture b, c and d the majority of cb people answered correctly. this result was surprising and unexpected, especially if compared with the results of test 2. considering the aim of this work, this test is very significant because the daltonized patches are reported inside the painting, thus the color differences are seen inside a context with edges and gradients. this test is the one in which the variance in the answers has increased the most and the paintings d and e are the ones which cause more errors in the answers. the answers given by the cb test group are more heterogeneous and, even in this case, the second test created the biggest variance and a greater number of errors. despite the presence of edges among colors, cb, but also some ncb fig. 5. comparison of the answers given in test 1 by ncb and cb subjects. the correct answers are evidenced in green. in these plots it can be noticed that pic. d is the one which causes less error in cb people, while pic. a and pic. e causes the biggest error and variance in the answers. fig. 6. comparison of the answers given in test 2 by ncb and cb. the correct answers are evidenced in green. in these plots the pic. d in ncb presents the lowest value of correct answer. in cb subjects the answer variance is high and pic. e causes the lowest value of correct answers. fig. 7. comparison of the answers given in test 3 by ncb and cb. the correct answers are evidenced in green. this is the test in which cb people perform better, especially for pic. b and pic. d. the images pic. e and pic. a produce high error also in this case. a test on color discrimination in complex scenes for a better comprehension of color blindness 78 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130209b people, could not see the difference between the different test images. a preliminary explanation of this result could rely in the assimilation phenomenon of the human visual system. it is clear that this phenomenon must be f urther studied and analyzed from the physiological, neurological, and psychological point of view, but this result demonstrates the presence of a spatial elaboration of the signal. this is in line also with the strong decrease of errors in cb test group switching from the second test to third test. as a consequence, if in ncb people the number of correct answers is robust and constant in the three different tests, f or cb people the strong variations could suggest the presence of a spatial elaboration of the signal switching f rom a situation to another. considering now the single paintings (see appendix a), we can generalize saying that the paints a, b and c represents subjects which have color arrangements similar to natural scenes, despite the paintings d and e which have non-natural color distribution. this f act could have led to a greater error in ncb and cb test group, especially in the second and third tests, where all the daltonized colors could be considered probable (e.g., in picture a where an apple is colored in red, green and yellow). on the other hand, considering the setup for test 1 and test 3, in an abstract image like picture d (see figure 4a in the appendix), the original painting is clearly distinguishable f or ncb as well as f or cb people. this happens also for picture b, which is more similar to a real image, even if in test 1 the number of error and n/d answers is still high. considering the single subject analysis, and in particular the cb test group, the subjects can easily be divided in two groups. on one side we have the subjects who gave more than half wrong or n/d answers (subjects 1, 2, 3, 5, 7, 8 fig. 8. summary of answers given by the fifteen ncb subjects. fig.9. summary of answers given by the fifteen cb subjects. a test on color discrimination in complex scenes for a better comprehension of color blindness 79 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130209b and 12) and, on the other side, the subjects who gave more than half correct answers (subjects 4, 6, 9, 10, 11, 13, 14 and 15). from this analysis it is clear that all the cb people, who clearly do not perform as well as the ncb test group, can have not only different types of color vision def iciencies, but also different severity levels. clearly, also this point should be better analyzed and studied. in addition, as f uture work, f urther analysis both in remote and in laboratory conditions should be made, in order to evaluate not only the role of spatial arrangement intended as color distribution in the image, but also the role of dif ferent monitor qualities and sizes, and observing conditions in the assessment of color. 5. conclusion color perception is a complex phenomenon which involves not only the signal transduction in the human retina, but also the signal elaboration made by the visual cortex. color blindness is mainly modeled and studied at the retinal level, since it is an inherited problem which af f ects the development of one or more type of cone cells. in order to overcome the retinal level in color blindness study and analyze the role of edges and gradients in color vision, we perf ormed three color perception tests. aim of this study is to assess if the spatial arrangement in which colors are inserted may increase the ability to discriminate colors in cb people. this was a preliminary study, and f urther studies and analysis f rom the physiological, neurological, and psychological point of view are needed, but this experiment has been useful to suggest that the integration of spatial arrangements in models of vision is mandatory, as well as in color blindness diagnosis tests. this trend has been demonstrated by the test results, but also by the analysis of the single subjects’ answers, which show that color def iciency presents different levels of severity. this specific analysis aims to be a f urther small preliminary step in the direction of rising the awareness of the scientific and medical community on the necessity of developing new methods and techniques able to diagnose not only the presence/absence of color blindness, but also at evaluating and measuring the severity level in real context and not just on isolated patches, not representative of real working tasks in conclusion, with this preliminary experiment we aim at exploring the boundaries of the actual knowledge about color vision deficiency, evidencing that this phenomenon cannot be studied just at the retinal level but must also consider the visual spatial mechanisms. 6. aknowledgement the experiments presented in this paper have been made thanks to the collaboration between the department of computer science of università degli studi di milano, with the istituto di medicina aerospaziale of rome as part of the corisamil project screening del daltonismo in profili operativi complessi del volo militare: studio e analisi di nuove metodologie di diagnostica alternativa. 7. conflict of interest the authors declare no conflict of interest. 8. declaration of funding sources the authors received no specific funding for this work. 9. short biography of the authors sofia scipioni – she is a student of “cultural heritage conservation science” at università degli studi di milano. she graduated in “science and technology f or studying and preserving the cultural heritage and inf ormation storage media” and now her interests and studies are f ocused on the different way of materials deterioration connected with cultural heritage. chiara andrea lombardi – she graduated in 2019 in “science and technology for studying and preserving the cultural heritage and inf ormation storage media” at the university of milan with a thesis dealing with the identification of pigments through analytical investigations on roman wall painting f ragments. she is currently obtaining her master's degree course in “cultural heritage conservation science” at the university of milan. luca giuliani – he is a master degree student in computer science. he obtained his bachelor degree with a thesis concerning a simple implementation of a space variant model f or the retinal-cortex vision. currently he is f ocusing on distributed systems and iot devices which could be applied to study human visual perception. andrea mazzoni – ophthalmologist md, phd, italian air force medical officer serving at the aerospace medicine institute in rome. his main task is military and civilian airworthiness. specialized in clinical and instrumental diagnosis, mostly in anterior segment of the eye. he has been dealing with human visual system perception of colors in a long time. he is currently the head of the research study: "screening of color blindness in complex operational profiles of military flight: study and analysis of new alternative diagnostic methodologies” collaborating with unimi, the university of milan. roberta marcucci – ophthalmologist md, italian air force medical officer at aerospace medicine institute in rome. her clinical field of application is aviation medicine and the assessment of medical f itness of military and a test on color discrimination in complex scenes for a better comprehension of color blindness 80 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130209b civilian aviation personnel, according to their special duty status. her prof essional background includes medical retina, cornea, refractive surgery. alice plutino – she recently obtained a phd in computer science at università degli studi di milano. her research interests are: color science, colorimetry, image enhancement, image digitization and archiving, with a particular interest in cultural heritage applications. she is author of a book on film restoration and of several journal and conf erence papers of national and international relevance. alessandro rizzi – he is full professor at the department of computer science at the university of milano. he is doing research since 1990 in the f ield of digital imaging with a particular interest on color, visualization, photography, hdr, vr and on the perceptual issues related to digital imaging, interfaces, and lighting. he is member of several program committees of conferences related to color and digital imaging, and author of about 400 scientific works. references bonanomi, c. et al., 2017. an app-based assessment of sicharda, an image enhancer for color-blind people. journal of imaging science and technology, volume 61, number 4,, pp. 40405-1-40405-9. brown, a. & lindsey, d., 2004. color and language: worldwide distribution of daltonism and distinct words for blue. visual neuroscience 21, pp. 409–412. colblindor, 2006-2021. coblis — color blindness simulator. 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[online] available at: https://www.google.com/forms/about/ (accessed: 12 september 2021). hubel, d. h., 1995. eye, brain, and vision. s.l.:scientific american library/scientific american books. hubel, d. h. & wiesel, t. n., 1998. early exploration of the visual cortex.. neuron , volume 20.3, pp. 401-412. imagej, 2021. download. [online] available at: https://imagej.nih.gov/ij/download.html (accessed: 12 september 2021). judd, d. b., 1945 . standard response functions for protanopic and deuteranopic vision. journal of the optical society of america (josa), volume 35.3 , pp. 199-221. land, e. h., 1959. experiments in color vision. scientific american, volume 200.5 , pp. 84-99. land, e. & mccann, j., 1971. lightness and retinex theory. journal of the optical society of america (josa), pp. 1–11. levin, l. a., kaufman, p. l. & alm, a., 2011. adler's physiology of the eye. s.l.:s.n. mccann, j. j. & rizzi, a., 2011. the art and science of hdr imaging. s.l.:john wiley. nathan, j., 1999. the evolution and physiology of human color vision: insights from molecular genetic studies of visual pigments. neuron 24, pp. 299-312. osterberg, g., 1935. topography of the layer of rods and cones in the human retina. s.l.:acta ophthalmol. rizzi, a., 2021. colour after colorimetry. coloration technology, volume 137, pp. 22 28. rizzi, a., eschbach, r., quaranta, a. & bonanomi, c., 2014, reprinted in vol. 13, july 2015. modified ishihara test to study the role of edges in color discrimination. italian journal of aerospace medicine , vol.11 . sharpe, l. t., stockman, a., jägle, h. & nathans, j., 1999. opsin genes, cone photopigments, color vision, and color blindness. cambridge university press, pp. 3–5. https://www.color-blindness.com/coblis-color-blindness-simulator/ https://www.color-blindness.com/coblis-color-blindness-simulator/ https://www.google.com/forms/about/ https://imagej.nih.gov/ij/download.html a test on color discrimination in complex scenes for a better comprehension of color blindness 81 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130209b appendix a fig.1a. first, second and third tests for the picture a (caravaggio, basket of fruit). fig.2a. first, second and third tests for the picture b (giorgione, the tempest). a test on color discrimination in complex scenes for a better comprehension of color blindness 82 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130209b fig.3a. first, second and third tests for the picture c (hayez, the kiss). fig.4a. first, second and third tests for the picture d (gauguin, arearea). a test on color discrimination in complex scenes for a better comprehension of color blindness 83 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130209b fig.5a. first, second and third tests for the picture e (van gogh, sunflowers). 45 color culture and science journal vol. 14 (2) doi: 10.23738/ccsj.140206 more than a tube of color the emotion lupe voss 1 , sherman wong 2 1 color space™. lupe@colorspacehair.com 2 collective beauty brands. sherman.wong@collectivebb.com corresponding author: lupe voss (lupe@colorspacehair.com) abstract the relationship a colorist builds with their chosen products is deeply emotional and is heavily dependent on trust and confidence in their performance. with this confidence a colorist’s focus can remain on their ability to ensure consumers’ happiness through proper product choice, which directly affects the livelihood of a colorist. when a person sits in the colorist’s chair, there can be trepidation, anxiousness, eagerness, or excitement. as with all relationships, understanding these emotions builds trust between consumer and colorist. how people feel about their hair color is intimate and unique to each individual. color creates a connection to how people see themselves, and thus a reflection of how one is perceived. we will look at the perception and psychology behind different colors of hair, such as blonde, red, brunette, and grey. these intended consumer benefits – confidence, happiness, comfort are often derived from this sacred service. keywords: relationship, psychology, hair color, emotional connection, trust received 11/03/2022; revised 09/09/2022; accepted 30/09/2022 more than a tube of color – the emotion 46 color culture and science journal vol. 14 (2) doi: 10.23738/ccsj.140206 1. introduction a tube of hair color has a broad impact on lives. like most products used in the beauty industry, hair color is utilized as a relationship and confidence builder. the emotional connection to hair color is intrinsic to these relationships. a connection to the colorist, from the colorist to the consumer, and from the consumer to their chosen hair color, drives the color product choice, and our chosen hair color result. 2. theory hair color service is a relationship of the colorist and the consumer, achieved through a tube of hair color. product choice creates trust and confidence in this relationship. the sacred hair color service triggers emotions and influences the perception of an individual. 3. method two questionnaires were developed to investigate the behaviors and opinions of hair color consumers and professional hair colorists. questions are formatted in multiple choice and short answer form. a total of 500 hair color consumers, including 281 professional hair colorists were surveyed. data collection was conducted between may 17, 2021 to june 17, 2021. 4. results and discussions 4.1. product choice when selecting a hair color line, the most important factors to a colorist are the performance, the customizability, and the environmental impact. survey respondents are prompted to select top deciding factors when selecting a hair color line. figure 1 is an illustration of the result. critical objective for a hair colorist is to ensure the consumer is happy with the hair color service and the hair color results. the ability to communicate, understand, and deliver the consumer's needs is the cornerstone for the consumer to trust the colorist and the colorist’s ability to execute the sacred service the hair color service. beautiful, healthy, shiny hair is always the goal. a happy consumer will share the hair service experience with others, which is one of the most important ways a colorist builds business. fig. 1. important deciding factors to selecting a hair color line 4.1.1. high performance when a colorist is choosing a hair color product to represent their work, quality is vital. trusting that the hair color will perform as expected builds confidence in the colorist to achieve what the consumer expects. amongst the surveyed professional hair colorists, 19% of the respondents experience 100% success rate; 58% of the respondents experience 90% success rate; 19% of the respondents experience 75% success rate; and 4% of the respondents only experience 50% success rate. no surveyed colorists use a hair color line that delivers below 50% success rate. hence, performance of hair color provides the confidence for colorists to deliver consumer’s needs (table 1, left). along with trust, hair color performance builds loyalty in both the colorist and consumer. the colorist is loyal to the hair color brand and the consumer is loyal to the colorist. analysis shows that 51% of the respondents, who are professional hair colorists, use a single hair color line. this is an indication of colorists trusting the performance of their selected choice of hair color product (table 1, right). 230 199 150 113 93 94 60 58 79 0 50 100 150 200 250 high performance customizable environmentally conscious easy to use creativity ingredients brand representation cost other more than a tube of color – the emotion 47 color culture and science journal vol. 14 (2) doi: 10.23738/ccsj.140206 success rate of existing hair color line(s) in achieving anticipated hair color results percentage of hair colorist using multiple hair color lines table 1. analysis of hair color lines confidence in a product connects directly to a colorist on an emotional level. quality components within the tube of hair color, supported by a foundation of strong education, create predictable and consistent results. when predictable results occur, the colorist trusts the product performance, and confidence is established. 4.1.2. customizable hair color the ability to be creative with hair color is very appealing to a colorist. marketing a customizable hair color to consumers is a natural fit with the current trend of “individuality”. colorist needs to assess a series of variables when formulating hair color (fisher, et al., 2016). in order to create the desired outcome, variables affect a color formula and need to be considered. using the same formula on different clients will not produce the same results. variables in hair color formulation are natural remaining pigment, developer choice, hair texture, hair type, hair density, percentage of grey. natural remaining pigment, or underlying pigment, is the pigment exposed in the hair when lifting or lightening natural hair color during a hair color service. natural remaining pigment will contribute to the result if not neutralized, enhanced, or refined with the right hair color product (fisher, et al., 2016). developer choice is an important element in formulation because it acts as a time control of product activation. developers, with a ph of 2.5 to 4.5, are oxidizing agents used with demi-permanent and permanent colors, lighteners, and toners (fisher, et al., 2016). hair color developer is a hair color activator with different processing times and power strengths. hair color developers come in a variety of processing times and strengths. this product is mixed in various ratios for specific formulas. developers are also known referred to as catalysts to activate the process of hair color. hair texture is referred as the movement in the hair. straight, wavy, and curly hair indicates the natural hair color level to use when creating a hair color formula. straight hair is reflective of light. therefore, the colorist will utilize a hair color formula that would match the desired level of hair color. wavy hair is reflective and shadowed within the movement of the texture hair. a formula for this hair texture would be adjusted one-half to one shade lighter than the desired level of hair color. curly hair is absorbent of light and should be adjusted one to two levels lighter than the consumer's desired result (color space™, 2021). hair type is referred as the diameter of the hair shaft. hair type determines what developer to utilize in order to achieve the correct lift or deposit of hair color within the formula. fine hair does not need as much strength in the formula. this hair type is also fragile compared to medium or coarse hair types. medium hair would be is considered the standard hair type, and usually a standard catalyst can be utilized. coarse hair requires 0% 4% 19% 58% 19% 25% success 50% success 75% success 90% success 100% success 49% 51% yes no more than a tube of color – the emotion 48 color culture and science journal vol. 14 (2) doi: 10.23738/ccsj.140206 more developer strength; a stronger catalyst is required to achieve the final desired outcome (color space™, 2021). hair density is the quantity of hair per square inch. thinner hair has lesser hair per square inch; and thicker hair has more hair per square inch. hair density indicates to the colorist the hair’s natural starting level. the colorist identifies how many levels to lift or deposit hair color. the colorist also determines the correct product to achieve the desired result while maintaining the integrity of hair after the service. the thinner the hair, the more light is reflected through, and the hair appears lighter. thicker hair can appear darker because the light cannot travel through as easily (color space™, 2021). percentage of grey tells the colorist how much of the grey coverage additive to be included in the formula (fisher, et al., 2016). the ability to customize hair color allows the colorist to efficiently address important variables in each formula, and to remain unique and creative while regularly being challenged to elevate their craft to the next level. product performance and formulation ease are a must when working with customizable hair color. a colorist works with tight schedules and cannot spend extra time adjusting an unexpected hair color result. in the beauty industry, time has a direct correlation to revenue. 4.1.3. environmental impact because of the current state of the global environment, more companies in the beauty industry are focusing on sustainability. pioneering beauty brands focusing on positive impact innovation and creativity are paving the way for eco-conscious products and green companies to take over the market and showing their less sustainable siblings that green is not only the new glamorous — it’s also a mean to preserve the wellbeing of our planet and the people who live in it (sparknews report in collaboration with cosmoprof worldwide bologna, 2019). colorists connect to hair color companies that advocate the following beliefs: clean ingredients, plant-based ingredients, vegan, peta friendly, innovations to make color easier to use. search engines are widely accessible. it is not uncommon for colorists and consumers to research where ingredients are sourced. one also expects the cleanest ingredients that give a quality performance while remaining sensitive to environmental impact. a clean product that is sensitive to the environment should be the goal for all hair color manufacturers. 4.2. confidence and trust 4.2.1. the confidence a consumer has in their colorist the relationship between the colorist and the consumer is a strong emotional connection. majority of the consumers, represented by 97% of the respondents in the questionnaire, trusts that the colorist is knowledgeable and competent to give recommendations and create suitable outcomes (table 2, left). there can be a lot of emotions connected to this trust. until this trust is established, there can be fear and anxiety before a hair color service. such emotions can return when adjustments are required. having a consistent, reliable product will help colorists to be successful; hence maintaining the established trust. trust in the colorist is established through different stages of the relationship. stage 1 before the first hair color appointment the consumer gets introduced to a colorist through avenue such as referral and research. 18% of the survey respondents trust their colorists through word-of-mouth reputation. stage 2 – after the first hair color appointment in the first appointment, the consumer and colorist are both getting to know each other. a solid consultation kicks off the relationship between the colorist and consumer. the consumer is anxious, fearful, insecure, and vulnerable sitting in the colorist’s chair. this fear is alleviated with each question a confident colorist asks during the consultation, and as the consumer feels heard. 57% of the survey respondents trust their colorists after the first appointment. stage 3 – after the second and third hair color appointments during the second appointment, any adjustments needed stemming from the previous service is addressed. this appointment can be pivotal in the colorist/consumer relationship. the consumer assesses how well the colorist performs the second service and understands the consumer’s needs. a consumer returning for their third appointment indicates that trust has been established. it is also apparent at this appointment that the colorist understands the consumer, and the consumer knows what to expect from the colorist. the consumer has built trust in the colorist to do what is right and that the colorist can adjust or correct anything the consumer does not like. 20% of the survey respondents trust their colorists after the second and third appointments. more than a tube of color – the emotion 49 color culture and science journal vol. 14 (2) doi: 10.23738/ccsj.140206 percentage of hair color consumers trusting the knowledge and competency of their colorists moment a consumer started to trust their colorist table 2. analysis of consumer’s trust towards their colorists stage 4 – trust established 95% of the surveyed respondents would have established trust to their colorists upon reaching stage 3 of the relationship (table 2, right). once trust is established, consumers will start to feel confident to the recommendations from the colorists. from the questionnaire surveying professional colorists, 22% of colorists agreed that 100% of their clients will allow them to select hair color for the clients with absolute trust. 38% of the colorist agreed that 75% of their clients will allow them to choose hair color for the clients with absolute trust. this is a significant indication that the established trust empowers the colorist to make appropriate recommendations to the consumer. when there is trust in the hair colorist, the consumer will return for future services. this trust is vital for the service provider since this is how revenue is generated. there are different benchmarks a service provider can review to measure the loyalty of the consumer. rebooking appointments for future hair color services is one of the benchmarks. studies found that an 80% rebooking rate on existing hair services will lead a hair professional to the top 10% of all earners in the hair industry (zoot, 2017). trust is one way to ensure consistent future revenue for colorists. a consumer bases their trust on the skill of the colorist and the performance of the product. the consumer wants to leave the salon with an experience of having expectations met, holding their head high, and feeling great. the colorist's livelihood relies on the customer happily paying for the provided service. hence, having a high-performing and reliable product is critical. 4.2.2. the confidence of a colorist there is a learning curve when starting to use a new hair color line. confidence is created through education, practice, and competency. knowledge is the key to overcoming fear of failure and learning how the product performs. there are two factors affecting the commitment to education time and money. as a service provider, taking time to attend education means taking time away from work and the potential of generating revenue working behind the chair and creating revenue. the commitment for a colorist to attend education is significant as earnings can be affected. paradoxically, education is crucial for the colorist to grow skills and increase future earnings. the decision to attend ongoing education is critical for the colorist to create future revenue. 98% of the surveyed colorists attend at least one class per year, and 84% of the surveyed colorists attend at least two classes per year. in addition, 81% of the surveyed colorists spend at least $100 usd on education annually. attending education can strike up insecurities of failure and build confidence in a hair colorist (akesha, 2017). colorists may be vulnerable to the educator’s judgement of the colorist’s current technical skills sets. however, education establishes necessary knowledge and strengthens the confidence of colorists, which also results in the assurance of consumer’s confidence in a colorist. 4.3. perception and emotion beauty consumers search for ways to look their best and feel beautiful. this personal quest can create specific 97% 3% yes no 18% 57% 20% 5% 0% based on word-of-mouth reputation after the first appointment after 2-3 appointments over a year other more than a tube of color – the emotion 50 color culture and science journal vol. 14 (2) doi: 10.23738/ccsj.140206 individual emotional responses which can in turn drive this search for tools that will help one feel more beautiful. hair color is a tool that can be utilized in fulfilling the emotional responses. examples of emotional responses include confidence, acceptance, self-expression, individuality, and self-representation. there is an intense psychological connection to hair color as well. there are two ideas to consider; how we perceive ourselves and how others perceive us. table 3 illustrates some preconceived ideas of an individual's personality or characteristics connected to hair color. words can be definitive in our perception. as we go through this world of opinions, we have heard how people see blondes, brunettes, reds, and grey hair. these perceptions and preconceived ideas of who we are influences employment, relationships, emotions and how we perceive ourselves. 4.3.1. perception of hair color and employment studies found that biases regarding personal appearance may affect judgement about a female’s applicant’s ability in a job application process (kyle & mahler, 1996). researchers from the university of queensland found blonde-haired women generally make salaries that are 7% higher than those of women with other-color tresses. they also learned that blonde women marry men who earn about 6% more than the husbands of non-blondes (shontell 2011). other studies also found that blonde women earn $870 more on average than brunettes and redheads (rosen 2011). however, these studies do not show a direct correlation between an individual’s hair color and their ability. when it comes to employment opportunity, physical appearance, specifically hair color, does influence the opinions and perceptions of hiring managers (watson, griggs and szeman 2020). it is important to recognize that preconceived perceptions of an individual’s hair color have a significant impact on the employment opportunity and their employment terms. positive negative blondes blondes, have more fun blondes always get their way popular glamourous low iq / weak blondes are only interested in their looks mean reds red heads are passionate wild / libidinous / impulsive quick-tempered hot-blooded / hot-tempered / angry get thing done funny / personality brunettes brainy brunette / smart sophisticated clever/witty down-to-earth / wholesome / sensible girl-next-door serious plain-looking / dull mousy villains grey knowing wise confident grey unrelatable grandmother / grandfather old unfavorable table 3. perceptions of blonde, red, brunette, grey 4.3.2. perception of hair color and relationships attraction is an important factor when we develop a new relationship. we are attracted to individuals with certain hair color, eye color, and body types. our personal experience with individuals of specific hair color impacts our perceptions on others who wear that same hair color. a study conducted by the badoo social network found that 60% of the men find brunette to be the most desirable. 33.1% said they think the most attractive hair color is brown hair, 28.6% preferred black hair, 29.5% of men preferred blondes, and 8.8% of them preferred redheads. results show that 61.7% of men prefer women with dark hair (weaver 2015). most individuals are attracted to the type they are familiar with, or curious of the type that is the extreme opposite. even if they have been comfortable dating blondes or redheads their entire dating years, they might still choose to meet and marry a brunette. the choice in a relationship is personal, but one can see more than a tube of color the emotion 51 color culture and science journal vol. 14 (2) doi: 10.23738/ccsj.140206 that the choice is often influenced by the perception of the perceived personality and characteristics of hair color. 4.3.3. perception and emotion behind grey hair a personal weighing of emotions is involved when the consumer decides when to cover grey hair and when to stop. in our survey, 40% of the total respondents do not have grey hair; 60% have grey hair. 78% of this grey hair population uses hair color to cover their grey hair; and the remainder 22% embrace their grey hair. emotionally, the decision to cover or grow out is individualized. the top two reasons our surveyed respondents choose to cover their grey hair is because covering greys makes them feel better and more youthful. there is a balance of feeling insecure with appearing old or appearing desperate to look young. in contrary, the top two reasons our surveyed respondents choose to grow out their grey hair is because it is less maintenance and like how they look. the decision to embrace the grey will arrive when a person is emotionally prepared. 4.3.4. perception of ourselves and emotion hair color plays a role in our identity. how we regard ourselves is paramount to our hair color choices. choosing the hair color that best suits our perception of who we are, blonde, red, brunette, or grey, is about selfidentification. how we think others perceive us is affected by our biases learned from our experiences. the emotional connection by how others regard us stirs in fear, insecurity, and uncertainty. most consumers strive for social acceptance and approval. there is often a feeling of joy when someone compliments our hair, as the compliment is a validation of the consumer’s hair color choice. 5. conclusions the hair color service that evokes emotions such as confidence, happiness, and comfort, is an important moment that changes how we feel about ourselves. these emotions are derived from the sacred hair color service and start with a tube of hair color. the relationship of a hair color product to the colorist, the colorist to the consumer, and the consumer to their hair, is profound. the relationship involves building trust and understanding, which results in an emotional impact to the consumer. the celebration of individuality is unique to how a consumer feels about their hair color choice. consumers show the world how they want to be perceived their statement and their self-expression. become aware of all the different hair colors surrounding you and see how you perceive them. know that there is a trusted tube of hair color that performs perfectly and is emotionally contributing to personal acceptance and happiness. 6. conflict of interest declaration the authors declare that there is no conflict of interest. no financial or personal interests have affected the author's objectivity. 7. funding source declaration the authors declare that this research received no financial funding. 8. acknowledgment the assistance provided by martin barriga, pat beaupre, ph.d, erik arveseth, was greatly appreciated. a special thanks to giannantonio negretti and orazio ray civello for their encouragement and support. finally, i could not have completed this without manual voss, who provides stimulating discussions as well as happy distractions to rest my mind outside of work. 9. short biography of the authors lupe voss • lupe is a salon owner, professional hair color educator, and one of the founders of color space™ hair color. lupe has been advocating the need for reimagined and inspired hair color education in the hair industry. she dedicates herself to developing hair color education programs that inspire hair industry professionals. sherman wong originally a computer engineer who worked in silicon valley, sherman found his passion lie in the hair industry. sherman is a passionate beauty industry professional who is always in pursuit to inspire. his enthusiasm for developing leading education programs is matched by his focus on sharing his knowledge of the craft. licensing terms articles published in the “cultura e scienza del colore color culture and science" journal are open access articles, distributed under the terms and conditions of the creative commons attribution license (cc by). you are free to share (copy and redistribute the material in any medium or format) and adapt (remix, transform, and build upon the material for any purpose, even commercially, under the following terms: you must give appropriate credit to authors, provide a link to the license, and indicate if changes were made. you may do so in any reasonable manner, but not in any way that suggests the licensor endorses you or more than a tube of color the emotion 52 color culture and science journal vol. 14 (2) doi: 10.23738/ccsj.140206 your use, you may not apply legal terms or technological measures that legally restrict others from doing anything the license permits. the authors keep the rights to further publish their contents where they want and can archive pre-print and post-print (submitted version and accepted version) and the published version of the pdf of their article with no embargo period. references akesha. (2017). hj (hairdressers journal international) 9 reasons to consider offering education in salon. available at: https://www.hji.co.uk/latest/9-reasons-consider-offering-education-insalon/ (accessed: 12 june 2021). color space™. (2021). reimagined hcm with color space™. toronto: s.n., p.10-24 fisher, j., held-perez, s. & stavrakis, v. (2016). pivot point fundamentals color. chicago, il, usa: pivot point international, inc. p. 36-72. kyle, d. & mahler, h. (1996). 'the effects of hair color and cosmetic use on perceptions of a female's ability'. psychology of women quarterly, p. 447-455. doi: 10.1111/j.1471-6402.1996.tb00311.x rosen, n. (2011). business insider blondes really do earn more money. available at: https://www.businessinsider.com/the-ugly-tax2011-8 (accessed: 30 june 2021). shontell, a. (2011). business insider if you look like this, your pay check will be higher than average. available at: https://www.businessinsider.com/if-you-have-any-of-these-20-physicalfeatures-your-pay-check-will-probably-be-higher-2011-2 (accessed: 30 june 2021). sparknews report in collaboration with cosmoprof worldwide bologna. (2019). sustainability in the cosmetic industry 2019, bologna, italy: cosmoprof worldwide bologna, p. 1-11. available at: https://www.cosmoprof.com/media/cosmoprof/cosmotalks/aziende%25 20impactxbeauty/cpbo_impact_for_beauty.pdf (accessed: 26 may 2021). watson, b. f., griggs, t. l. & szeman, m. (2020). 'when hair color influences job marketability: the impact of red hair color on perceived attributes and employment outcomes for caucasian male and female job applicants'. journal of business, industry and economics, volume 25, p. 33-63. weaver, n. (2015). your tango men find this hair and eye color combo the sexiest. available at: https://www.yourtango.com/2015271623/this-is-the-sexiest-hair-eyecolor-combo-says-study (accessed: 30 june 2021). zoot, i. (2017). modern salon top 5 rules of client retention. available at: https://www.modernsalon.com/376066/top-5-rules-ofclient-retention (accessed: 03 june 2021). cultura e scienza del colore color culture and science 74 cultura e scienza del colore color culture and science | 09 | 2018 | lecca m. and da pos o. issn 2384-9568 1michela lecca lecca@fbk.eu 2osvaldo da pos osvaldo.dapos@unipd.it 1fondazione bruno kessler, center for information and communication technology, technologies of vision, trento, italia; 2università degli studi di padova, italia communications and comments in the last number of this column, we have discussed about the meaning of color perception. we have shown that color perception is a concept difficult to be defined and explained. the main difficulty in giving a unique, simple definition of color perception is due to the fact that there is no agreement about the relationship between sensation, perception, and cognition. in a phenomenological frame of reference. perception is independent from cognition, although sometimes it can be affected by it (that is by past experience, memory, hypotheses, interpretations, and so on). the laws of perception are basically the same in humans and in animals. in a cognitive frame of reference on the contrary color perception depends on high level, cognitive features, that are deeply influenced by cultural heritage and societal issues; the law of perception are essentially different in humans and in animals. as a consequence, theories about color perception may vary from time to time and from person to person. basically, our perceptual system strongly couples colours and emotions, and these in turn can be influenced by culture. let’s think of many expressions, like “red passion”, “vie en rose”, “blue blood”, “black friday”, where colours clearly denote an emotion or its strength or a particular condition or situation. since societal, historical, cultural features vary in time, colour connotations also change. an interesting example for this is given by the recent web discussion about the colour names and colour perception by ancient greeks [1][2][3]. among the many web-pages dedicated to this topic, that attracted much attention, here we mention this one: https://aeon.co/essays/can-we-hopeto-understand-how-the-greeks-sawtheir-world in this page, professor maria michela sassi, expert of ancient philosophy and ancient thought from pre-socratic to aristo telic ages at pisa university (italy), reports a short analysis of the use and of the meaning of the colour terms in the ancient greek literature, with particular attention to some parts from the wellknown poem odyssey by homer. her work starts from the observation that “the ancient greek experience of colour does not seem to match our own.” for instance, in odyssey, the colour term blue is never used to describe sky and sea. in particular, in many parts of odyssey, the sea is pansy-like, wine-like or purple, while sky is like iron or bronze (see figure 1). in addition, the colour term chloros denotes both green (like grass) and yellowish tones. xanthos indicates yellow and red as well. the description of the object colours provided by the ancient greek is very surprising for us, who use the expressions blue sky and blue sea, green plants and grass, and distinguish the orange-reddish colour of the fire and of the amber from the yellow of the sun. sailing on the wine-like sea towards foreign people, i finally put in harbor with ships and mates. coloumn νuν δ’ ὧδε ξὺν νηὶ κατήλυθον ἠδ’ ἑτάροισιν πλέων ἐπὶ οἴνοπα πόντον ἐπ’ ἀλλοθροόυς ἀνθρώπους [omero, odyssey, ii, v. 183, translated by m. lecca] 75 cultura e scienza del colore color culture and science | 09 | 2018 | coloumn. communications and comments issn 2384-9568 the use of colour terms can be affected by many factors: direct perception, linguistic style, stereotypes, poetic licence. many scholars in the last two centuries defined the greek use of colour terms a peculiar oddness, and many of them imputed the colour linguistic poverty of the greeks to physical problems in capturing and processing the light wavebands, i.e. to colour blindness. today, a theory about this is that the greek colour terminology on the one side depends on perceptual experience, which was ‘normal’ (not ‘defective’), but on the other side it can adapt to poetic demands, that is the colour terms are used and interpreted according the cultural greek style of expressing poetry. the greek colour oddness is thus the greek colour culture. as professor sassi said, greeks perceive blue as we do, but they were not interested in using it to describe the colour of the sky and of the sea , that were described as yellowish and wine-like upon their culture, psychological feeling or expressive needs. sky was iron or bronze-like because it was supposed to be like an up side down bowl covering the earth [3]. in many parts of odyssey, the sea is called purple. the word purple comes from the greek word porphyria (πορϕύρα), which means seething, troubled [2] and refers to the procedure to produce the colorant purpura in the ancient world. in homer’s poetry, it may be considered a way to describe the evil sea that brings ulysses from one coast to another, far from his family and home. this last observation leads us to consider the problem of associating colour linguistic terms to perceived colours on the one side, and to stimulus colours on the other side. different theories has been proposed and many experiments have been designed to disentangle the relationship between colour stimulus and colour names. in his commentary [4], rolf g. kuehni asserts that the first reference of colour terms is often made to colours understood as “color stimuli” or “objective colors”, while, on the basis of the fundamental distinction between perceived and stimulus colours, colour terms should primarily refer to the ‘perceived’ colours. moreover, verbal colour descriptions should not be made in terms of physical properties (it would involve the stimulus error), as often happens. this error is often made because of the difficulty of verbally describing private perceptual experiences, which on the other side can be inter-subjectively communicated by verbal language despite the difficulty. figure 1: were sea and sky really wineand bronze-like in the ancient greece? 76 cultura e scienza del colore color culture and science | 09 | 2018 | lecca m. and da pos o. issn 2384-9568 in [5]. liliana albertazzi and osvaldo da pos describe a set of experiments to identify the references of colour categories in italian language. in these experiments, a number of volunteers with different age and gender, were asked to produce through special software digital colours on a screen corresponding to a set of italian colour names (giallo/yellow, rosso/verde, blu/ blue, arancione/orange, viola/bluish purple, lime/lime, carota/carrot, and so on ... a tentative english translation in italics). the assumption was that there is a special connection between perceived colours and corresponding colour stimuli, so that the colour perceived by the participant who produced the digital colour is about the same colour other people perceive when looking at that colour stimulus. the research showed that most colour terms among those used in the experiments refer to specific perceived colours, since the ‘corresponding’ colour stimuli are significantly different. moreover, other colour terms on the contrary refer to the same set of perceived colours, because the difference between the sets of colour stimuli is not statistically significant: the conclusion is that these terms are synonyms. however, in [6], the same authors point out that the perceptual categorization of colours can be “implicit” that is not verbally objectified: this means that grouping the colours by visual perception, i.e. ordering colours by their visual similarities, is independent on linguistic categories and provides a stable and, let’s say, universal way to classify colours. as already discussed in the previous number of this column, colour perception is something more than colour sensation, as it entails a number of interactions between different stimulated areas of the retina; moreover it can be also strongly influenced by previous experience and cultural heritage. this is an important cue to understand the colour names and the description of the object colours in the greek literature: it explains once again the wine-like and iron-like colours of sea and sky. the ancient greek literature is an interesting example of how the cultural features (e.g. language, material production, science conviction, ...) influence colour naming and viceversa. therefore, the lesson is that while colour sensation (i.e., colour seen in isolation, like through a hole on a uniform background) has an universal aspect, colour naming does not. in addition, colour perception depends on a complex set of spatial and temporal interactions which can be quite different figure 2 on right: reproduction by michela lecca of “study of a figure outdoors: woman with a parasol, facing left” by claude monet (1886. musée d’orsay). on left: here, the woman modern dressed, with metallic and glittered cloths. how do the new materials change the color sensation and the color perception? 77 cultura e scienza del colore color culture and science | 09 | 2018 | coloumn. communications and comments issn 2384-9568 case by case: thus, color perception is not immutable, like the quintessence of the aristotelic celestial spheres, but it is an extremely varying concept [7][8]. the historical problem of colour naming and the meaning of colours has been treated many years ago also by some members of the colour group, see [9], but it would be interesting proposing a novel discussion about this topics, also by considering how internet and the novel, recent technologies have changed our colour culture. another important issue is to understand how the new techniques for colour production and the invention of new materials affect colour perception [10] [11], by creating new colour effects or variations in the modes of appearance, e.g. metallic tints, glittered colours, plastic reflections, and so on (have a look at figure 2). finally, we remind that these topics will be soon discussed during the munsell centennial color symposium, that will be held in boston (ma) on june 10-15, 2018, and organized by the inter-society color council and by the international colour association [12]. acknowledgements: michela lecca expresses her gratitude to luigi cordisco, which has provided the starting point for this discussion, i.e. the link to the work of prof. sassi. bibliography [1]https://it.quora.com/qual-%c3%a8-una-possibileinterpretazione-dellepiteto-omerico-οἶνοψ-πόντοςmare-color-del-vino [2]http://www.piegodilibri.it/olimpo-letterario/lapercezione-del-colore-nel-mondo-greco/ [3]http://www.istitutoeuroarabo.it/dm/i-colori-nelleculture-e-nelle-lingue-antiche-e-moderne/ [4] kuehni, rolf g. “does the basic color terms discussion suffer from the stimulus error?.” journal of cognition and culture 7.1 (2007): 113-117 [5] albertazzi, liliana, and da pos, osvaldo. “color names, stimulus color, and their subjective links.” color research & application 42.1 (2017): 89-101. [6] da pos, osvaldo, and liliana albertazzi. “it is in the nature of the colours.” seeing and perceiving 23.1 (2010): 39-73. [7] manlio brusatin, storia dei colori, piccola biblioteca einaudi, torino 2001. [8] carastro, marcello, ed. l’antiquité en couleurs: catégories, pratiques, représentations. editions jérôme millon, 2009. [9] lia luzzatto e renata pompas. il significato dei colori nelle civiltà antiche, milano : rusconi, 1988 [ 1 0 ] h t t p : / / w w w . t r e c c a n i . i t / e n c i c l o p e d i a / colore_%28enciclopedia-dell%27-arte-antica%29/\ [11]https://www.artsy.net/article/the-art-genomeproject-a-brief-history-of-color-in-art [12] https://munsell2018.org/ microsoft word 150101 7 color culture and science journal vol. 15 (1) doi: 10.23738/ccsj.150101 a review based on oled lighting conditions and human circadian system ayse nihan avci 1 and saadet akbay 1 1department of interior architecture, çankaya university, ankara, turkey. nihanavci@cankaya.edu.tr, akbay@cankaya.edu.tr corresponding author: ayse nihan avci (nihanavci@cankaya.edu.tr) abstract light is a form of energy that affects the human sleep cycle, working hours, alertness, productivity, and wellbeing. as one of the essential environmental factors, lighting requires extensive research to understand the human-environment interaction. earlier studies reveal that various artificial lighting technologies are utilized to investigate the human circadian system; experiments employing solid-state lighting (ssl) sources are still being conducted to determine how the human circadian system is affected. due to the advantages of oled (organic light-emitting diode) lighting, there is a need to enhance this form of artificial lighting in an indoor environment. this paper focuses on a literature review on artificial lighting sources, particularly oled lighting, used from the past to the present. this article also discusses how oled lighting can influence the human circadian system in terms of different characteristics of lighting in an indoor environment. keywords oled lighting, human circadian system, lighting technologies, human-environment relationship, lighting in an indoor environment received 11/10/21; revised 01/03/22; accepted 21/01/23 a review based on oled lighting conditions and human circadian system 8 color culture and science journal vol. 15 (1) doi: 10.23738/ccsj.150101 1. introduction light is radiant energy that ranges from gamma rays to radio waves. the human eye responds to this energy within the limits of the visible spectrum from ultraviolet to infrared. lighting technologies act as substitutes for natural light. lighting history might be defined as the evolution of efficient technologies for producing visible light in the required spectral area. several lighting fixtures have been produced over the centuries. they have been manufactured to meet the needs by modifying their shape, color, temperature, intensity, and rendering of light. they provide general illumination and are classified into three groups: incandescent, discharge, and solid-state lighting (ssl). figure 1 shows the evolution of artificial lighting technologies. incandescent lamps produce light by heating a tungsten filament to incandescence. discharge lamps have light through an electric discharge in gas and require control gear between the lamp and the power supply. fig. 1. evolution of artificial lighting technologies (de almeida et al. 2014: 32). the term ‘solid-state lighting’ is also called ‘electroluminescent lighting’ since it produces electromagnetic radiation in response to power current; this process does not require heat and electric discharge via gas. as a result, they are cooler and smaller than other lighting sources (innes, 2012). with the advent of new green ssl technology, the general concepts of artificial lighting sources have been changing (kar and kar, 2014). due to task performances, human comfort, and production of high-quality lighting, researchers have focused on hightech lighting sources that use more efficient ssl devices, have very long lifetime, resulting in lower maintenance costs, and have good physical robustness and compactness compared to other lighting sources (de almeida et al., 2014). earlier studies indicate that various artificial lighting technologies are used to explore the human circadian system; experiments employing solid-state lighting sources (ssl) (i.e., light-emitting diode [led]) are still being undertaken to understand how the human circadian system is affected. however, due to the advantages of organic light-emitting diode (oled) lighting, there is a need to use this form of artificial lighting in an indoor environment. due to the advantages of oled lighting, it has been a matter of curiosity why it is not used indoors more than other lighting technologies. it aims to expand the indoor-oriented use of oled lighting technologies and shed light on the studies carried out in different areas by considering the user profile. specifically, this paper focuses on a literature review of artificial lighting sources, particularly oled lighting, which also discusses how oled lighting can be utilized to alter the human circadian system in an indoor environment. most importantly, it has also the potential to change the design approaches by providing fresh knowledge for architects, interior designers, industrial designers, lighting designers, and lighting companies on how to effectively approach indoor lighting design with newer technologies for all users. creating optimal surroundings is predicted to reduce stress and enhance visual satisfaction and well-being, having a considerable influence on the human circadian system and greatly boosting the user's quality of life. 2. organic light-emitting diodes (oleds): the future of lighting technologies organic light-emitting diodes (oleds), one of the most significant advancements in the lighting industry, are unique and revolutionary ssl sources. oleds are a type of ssl source; however, they differ from other ssl sources in that they contain electroluminescence in organic compounds (kunić and šego, 2012). following bernanose and his colleagues’ initial innovation, in 1985, eastman kodak company explored many materials to improve this technique, and in 1987, the first oled devices were introduced. they were later developed by companies including samsung, lg, panasonic, and sony. oleds are currently used in various electronic products such as televisions, mobile phones, and automobiles. oleds are composed of multiple organic sandwiched between the cathode and the anode. they are semiconductive, emit light, and are manufactured on a substrate. the color of the light emitted is determined by the content of the organic layer. multiple layers (e.g., red, green, and blue) are mixed to produce any color, including white. oleds differ in structure, material, and emission type. they are classified into seven classes: passive-matrix oled (pmoled), active-matrix oled (amoled), transparent oled, top-emitting oled, bottom-emitting oled, foldable or flexible oled, and white oled (woled). a review based on oled lighting conditions and human circadian system 9 color culture and science journal vol. 15 (1) doi: 10.23738/ccsj.150101 oled lighting offers an entirely new realm of light interaction possibilities. oled is an ssl technology with numerous advantages over traditional alternatives. along with its design (i.e., being ultra-thin, featherweight, flexible, cool-to-touch, long-life span, and 90+ color rendering index), health and well-being (no blue light risk, no uv, circadian system friendly, no flicker, naturally diffuse, and glare-free), and sustainability (recyclable, 85% organic and glass materials, does not contain toxic materials, no thermal heat sink, reduced manufacturing footprint, and low power consumption) are among the benefits of oleds (thejokalyani and dhoble, 2014; hawes et al., 2012; why oled, 2020). 3. lighting and human circadian system in the 18th century, the term 'circadian' was investigated by french scientist jean jacques d'ortous de mairan (rossi, 2019). he notices that the movements of the flowers of plants continue during the day, although they are placed in an indoor environment and not exposed to sunlight. this finding indicates that the movements of the plants are controlled by an internal clock (vitaterna et al., 2001). plants, animals, fungi, and cyanobacteria have circadian systems (edgar et al., 2012). it is a 24-hour cycle internally created and influenced by external factors such as light and temperature. the circadian system has a daily process linked to brain wave activity, hormone production, core body temperature, cell regeneration, and other biological activities. these are all coordinates in the 24hour cycle of living beings. in addition, the human circadian system influences primary physiological factors such as sleep cycle, changes in body temperature and blood pressure, immune system activities (rossi, 2019), hormone system, and other psychological factors such as alertness level (cajochen, 2007), mood, behavior (legates et al., 2014), and well-being. light is a fundamental human need, providing both vision and non-visual impacts, including regulating the circadian system. it is essential to the human circadian system, accomplished through vision. one of the most complicated senses, vision, is the primary mechanism by which humans perceive their surroundings. the first thing to understand about the visual system is that it comprises more than just the eye. the interaction between the eye and the brain results in vision, in which humans experience lights in their environment. understanding this process leads to the establishment of such an environment. understanding the biological context that led to vision requires considering the eye and brain as a unit. the eye governs the physiological effects of light in humans. when light enters the eye, it activates retinal photoreceptors, which convert photic information into neural impulses transmitted to various parts of the brain via ganglion cells. for many years, it was considered that the human retina included just two types of photoreceptors: rods and cones; nevertheless, roughly two decades ago, another distinct photoreceptor type was discovered in the mammalian eye. these retinal photoreceptors are specialized ganglion cells that contain the photopigment melanopsin and are inherently photosensitive, hence being dubbed intrinsically photosensitive retinal ganglion cells (iprgcs) (berson et al., 2002; hattar et al., 2002; provencio et al., 1998, 2000). when light falls on the retina, photoreceptors and cells transfer the light to the brain's suprachiasmatic nucleus (scn), which regulates our daily circadian systems. scn is an organizer for the recurrence of our daily physiological functions and psychological states like hormone secretion, body temperature, mood, well-being, and alertness (tähkämö et al., 2019). figure 2 shows the schematic illustration of the neuroanatomical underpinnings of the physiological effects of light. fig. 2. schematic illustration of the neuroanatomical underpinnings of physiological effects of light (vetter et al. 2021: 2). 4. relationship between lighting and human circadian system in an indoor environment most people moved from an outdoor environment to an indoor environment. this has been shown to have a negative impact on our health, productivity, visual comfort, mood, and happiness. however, with the recent discovery of a new photoreceptor in the eye and a better understanding of the process underlying non-visual biological impacts, we may be able to define lighting scenarios that ensure healthy individuals remain healthy even when working in indoor environments. aside from the benefits to individuals' health and well-being, good lighting contributes to improved job performance (speed), fewer mistakes and rejections, increased safety, fewer accidents, and decreased absenteeism. this all adds up to increased productivity. indoor lighting design differs significantly from that of lighting for the circadian system. in general, the latter a review based on oled lighting conditions and human circadian system 10 color culture and science journal vol. 15 (1) doi: 10.23738/ccsj.150101 approach has placed an emphasis on visibility and related issues such as glare and shadow reduction, color rendering, safety, and space appearance. designing for non-visual impacts of light, such as the circadian system, requires distinct lighting design objectives and, as a result, metrics and parameters related to the physical and psychological effects of light that lighting designers do not currently use. in the literature, various studies have been carried out within the scope of human-centric lighting by considering the different characteristics of light. although the studies do not directly address the effect of indoor lighting systems on the circadian system, the topics investigated are related to this field. kuller and wetterberg (1993) researched the brain-wave patterns (eeg) of people in a lab set up to imitate an office setting, once with a relatively high illuminance level (1700 lx) and once with a relatively low illuminance level (450 lx). lower delta waves (the delta activity of an eeg indicates tiredness) are associated with higher illuminance levels of illumination, indicating that bright light has an alerting effect on the central nervous system. non-visual flicker under fluorescent lighting has been shown to alter performance and mood, with individuals reporting a more pleasant mood under 2000 lx than under 300 lx in office environments (daurat et al., 1993). although 500 lx is considered the standard, it has been suggested that lower illuminance levels might be achieved without compromising the user experience (fotios, 2011). revell et al. (2006) conducted a study to investigate the non-visual effects (such as mood, alertness) of light of four different wavelengths at 420, 440, 470, and 600 nm on 12 participants. the results indicate that light with a wavelength of 420 nm produced more wakefulness than light with a wavelength of 470 nm or even 600 nm. the effects of illuminance (300 lx or 500 lx) and color temperature (4000 k or 6500 k) were assessed in specially designed office rooms for the study that participants preferred 500 lx and warmer (4000 k) lighting. there were also some impacts of spectral power distribution rather than simply cct (islam et al., 2015). in a study, rossi and casciani (2018) investigated natural lighting conditions in an indoor environment to explore the contribution to the well-being of the elderly and the invisible effects of lighting. the results sugget that older people might be exposed to low levels of natural lighting in the morning, which is essential for activating invisible responses and, as a result, synchronizing their circadian systems. since the millennium, new lighting solutions and advancements have focused on research themes such as light and health, user comfort, and the circadian system. many studies have been conducted to determine how led lighting conditions affect visual comfort under various illuminance levels (avci and memikoglu, 2017; fortunati and vincent, 2014). light has been demonstrated to have significant non-visual impacts on a variety of biological functions, including the regulation of the human circadian system. in any case, advances in technology can provide useful tools for designing circadian lighting. in this respect, leds provide crucial characteristics for manufacturing lighting solutions that previous light sources did not allow for, or only partially allowed for, due to low efficiency and high costs (rossi, 2019). in the literature, there are many studies related to the effects of led lighting on the human circadian system from different viewpoints (cajochen et al., 2011; chaopu et al., 2018; figueiro et al., 2018; nie et al. 2020). however, oleds, which emit less blue light than regular leds, are considered low-energy and medically friendly artificial lighting. a study by avci and memikoglu (2021) found that oled lighting exposure is more comfortable than led lighting exposure in terms of some visual comfort criteria in the indoor environment. ngarambe et al. (2021) investigated the impact of spectral power distribution (spd) on visual comfort, work performance, circadian energy, and mood. they used two types of lighting: led and organic light-emitting diode (oled). participants preferred oled for visual comfort, whereas led was chosen for improved job performance and mood. however, park et al. (2020) researched light exposure on circadian system and sleep. participants were randomly assigned to one of three different light conditions (oled, led, and dim light). melatonin onset was considerably delayed under led lighting when compared to dim lighting, but did not vary under oled lighting. yamagata university constructed the "smart mirai house" to test future lighting and other organic electronic devices. various lighting conditions may be researched by using different types of oled lighting displays to identify appropriate lighting for comfortable sleep and a well-controlled circadian rhythm (sano et al., 2021). furthermore, jo et al. (2021) conducted a study to assess the influence of oled lighting exposure on sleep quality and the circadian system, which investigates the effects of led and oled lighting conditions on the human circadian system at night. jo et al. (2021) suggest that oled can be a suitable replacement for led since its spectrum contains less blue light, which has the most significant impact on melanopsin in intrinsically photosensitive retinal ganglion cells. in addition, the effects of oled lighting conditions on the human circadian system, visual comfort, and well-being in an indoor office environment have been an interest for the authors of this article, where they have been investigated as part of a scientific research project. a review based on oled lighting conditions and human circadian system 11 color culture and science journal vol. 15 (1) doi: 10.23738/ccsj.150101 in contrast to earlier studies on the human circadian system, it aims to investigate the effects of oled lightingas an environmental factor on the circadian system, visual comfort, and well-being of the participants who perform their daily work in an office environment. finding the physiological and psychological effects of indoor lighting conditions on users is also among the research objectives. the circadian rhythmicity activity during the daytime is monitored using wrist actigraphy (actiwatch spectrum/philips respironics). the effects of oled lighting with two different color temperatures (3000 k and 4000 k) on the user were examined. when the results were discussed, 3000 k oled lighting conditions were generally found to be more positive. this study is intended to contribute to interior architecture by examining the application of oled lighting in indoor environments (avci and akbay, 2021). 5. conclusion to conclude, the primary goal should be to design an indoor environment that addresses health, comfort, wellbeing, and quality. this paper aims to expand the indoororiented use of oled lighting technologies and shed light on the studies carried out in different areas by considering the user profile. most significantly, it aims to alter the design approaches by offering architects, interior architects, industrial designers, lighting designers, and lighting companies new knowledge on how to properly approach indoor lighting design with modern technologies for all users. the influence of the circadian system should be included in lighting settings. since oled lighting technologies are more advantageous than other lighting technologies, their use should be expanded considering the impact on the user's circadian system and other environmental factors. 6. funding source declaration the authors received no specific funding for this work. 7. conflict of interest declaration the authors declare that there is no conflict of interest regarding the publication of this paper. 8. short biography of the authors dr. ayse nihan avci research assistant in the interior architecture department, çankaya university, ankara, turkey. member of the chambers of interior architects of turkey and the turkish national committee on illumination. her research interests include human-centric lighting, circadian lighting design, artificial lighting technologies, and color and light. assoc. prof. dr. saadet akbay associate professor in the interior architecture department, çankaya university, ankara, turkey. she received ba and mfa degrees from the department of interior architecture and environmental design at bilkent university, and a phd degree from industrial design at middle east technical university, ankara, turkey and postdoctoral degree from architecture at the university of lisbon, portugal. her research interests include colour perception, colour education, color and light, and design education. licensing terms articles published in the “cultura e scienza del colore -color culture and science" journal are open access articles, distributed under the terms and conditions of the creative commons attribution license (cc by). you are free to share (copy and redistribute the material in any medium or format) and adapt (remix, transform, and build upon the material for any purpose, even commercially, under the following terms: you must give appropriate credit to authors, provide a link to the license, and indicate if changes were made. you may do so in any reasonable manner, but not in any way that suggests the licensor endorses you or your use, you may not apply legal terms or technological measures that legally restrict othersfrom doing anything the license permits. copyright: the authors keep the rights to further publish their contents where they want and can archive pre-print and post-print (submitted version and accepted version) and the published version of the pdf of their article with no embargo period. references avci, a., n. and akbay, s. 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(2001) ‘overview of circadian rhythms’, alcohol research and health, 25(2), pp. 85-93. why oled (2020) available at: https://www.oledworks.com/inspiration/#why-oled (accessed: 29 june 2021). color culture and science cultura e scienza del colore ccsj volume 13 number 1 2021 issn 2384-9568 color culture and science journal cultura e scienza del colore ccsj jcolore.gruppodelcolore.it issn 2384-9568 doi: 10.23738/ccsj.00 ance e227716 road: the directory of open access scholarly resources registrazione presso il tribunale di milano n. 233: 24/06/2014 volume 13, number 1, april 2021 doi 10.23738/ccsj.130100 publisher gruppo del colore – associazione italiana colore www.gruppodelcolore.org registered office: piazza carlo caneva, 4 20154 milan (it) peer review process all articles submitted to the "color culture and science journal” are peer-reviewed according to the following procedure: first review level the associate editors evaluate each article in order to determine if the topic and content are of interest to the journal. once the article passes the initial review, the associate editors select several reviewers from the editorial board based on their expertise in a particular subject area or topic. second review level each article is reviewed by two or three reviewers and submitted to a blind peer review process where the reviewers are kept anonymous. reviewers are asked to evaluate the manuscript based on the following criteria:  originality  relevance to journal’s aims and scope  technical merit and/or validity  soundness of methodology  completeness of the reported work  conclusions supported by the data  correct acknowledgment of the work of others through reference  effectiveness of the manuscript (organization and writing)  clarity of tables, graphs, and illustrations  importance to color researchers  relevance to color practices if the article is accepted with major revisions, the author(s) are asked to improve the article according to the suggestions of the reviewers. the revised article will then be submitted to a further review. after collecting the reviewers' reports, the associate editors make a recommendation on the acceptability of the article to the editor-in-chief. editor-in-chief maurizio rossi (politecnico di milano, it) deputy editor alessandro rizzi (università degli studi di milano, it) associate editors josé luis caivano (universidad de buenos aires, ar) vien cheung (university of leeds, uk) marco gaiani (alma mater studiorum università di bologna, it) robert hirschler (serviço nacional de aprendizagem industrial, br) agata kwiatkowska-lubańska (academy of fine arts, kraków, pl) marcello picollo (ifac-cnr, it) verena m. schindler (chair aic s.g. environmental colour design, ch) renzo shamey (nc state university, usa) francesca valan (studio valan, it) editorial board members the complete and updated list of the editorial board members involved in the peer review process is available on the ccsj website: http://jcolore.gruppodelcolore.it/ojs/index.php/ccsj/about/editorialteam topics the ccsj accept papers on a wide range of topics on color, including and not limited to the following: 1. color and measurement/instrumentation. colorimetry, photometry and color atlas: method, theory and instrumentation; quality control and food coloring, dyes, organic and sustainable color. 2. color and digital. reproduction, management, digital color correction, image processing, graphics, photography, film and video production, printmaking and 3d print, artificial vision, virtual reality, multispectral imaging, data visualization. light field imaging. multi-sensor fusion. color localization, recognition, hdr imaging, adas systems. 3. color and lighting. metamerism, color rendering, adaptation, color constancy, appearance, illusions, color memory and perception, color in extra-atmospheric environments, lighting design, lighting technologies, visual comfort. 4. color and physiology. mechanisms of vision in their experimental and theoretical aspects, color vision and color appearance, deficiencies, abnormalities, clinical and biological aspects, synesthesia, health, well-being. 5. color and psychology. phenomenology of colors, color harmonies, color & form, perceptive, emotional, aesthetic and diagnostic aspects. 6. color and production. food and beverages, agriculture, textiles, plastic materials, ceramics, paints, gemology, color in the food industry. 7. color and restoration. archaeometry, painting materials, diagnostics and techniques of conservation, restoration and enhancement of cultural heritage. 8. color and environment. representation and drawing, urban planning, project of color, architecture, interior design, landscapes & horticulture, color and architectural syntax, territorial identities, biodiversity. 9. color and design. furniture, cmf design, fashion, textiles, textures, cosmetics, food design, museography. 10. color and culture. arts and crafts, history, philosophy, aesthetics, ethno-anthropology, graffiti, geology, sociology, lexicology, semantics, anthropology of vision, food culture and heritage, color naming. 11. color and education. pedagogy, didactics of color, aesthetic education, artistic education. 12. color and communication/marketing. graphics, communication, packaging, lettering, exposure, advertising. http://jcolore.gruppodelcolore.it/ojs/index.php/ccsj/about/editorialteam 3 color culture and science journal vol. 13 (1) issn 2384-9568 table of contents editorial 5 alessandro rizzi color and/is narration. the narrative role of color in wes anderson’s filmic images 7 greta attademo doi: 10.23738/ccsj.130101 bramante and his work of painted façades: bergamo and lombardy 14 patrizia falzone doi: 10.23738/ccsj.130102 the selection of colors for fashion collections in relation to color theory: a case study from the analysis of brazilian ready-to-wear 24 gisela costa pinheiro monteiro, camila assis peres silva doi: 10.23738/ccsj.130103 color in architecture among futurism, neoplasticism, rationalism (and more...) 32 anna marotta doi: 10.23738/ccsj.130104 lighting and color design in the live music show between new technologies and practice 43 andrea siniscalco doi: 10.23738/ccsj.130105 does gender have an impact on the color preferences in fashion products? 52 ítalo josé de medeiros dantas, aline gabriel freire, lívia juliana silva solino mariana nunes do nascimento and heloisa mirelly ferreira alves doi: 10.23738/ccsj.130206 4 color culture and science journal vol. 13 (1) issn 2384-9568 non-invasive identification of dyed textiles by using vis-nir fors and hyperspectral imaging techniques 61 greta peruzzi, costanza cucci, marcello picollo, franco quercioli, lorenzo stefani doi: 10.23738/ccsj.130207 the contribution of black color to visual rhetoric of brazilian packaging of hair care products. 70 camila assis p. silva, thamyres oliveira clementino, thalita gonçalves doi: 10.23738/ccsj.130208 quick gamut mapping for simplified color correction 79 matteo cereda, alessandro rizzi, alice plutino doi: 10.23738/ccsj.130209 the colors of public art in pescara: 4 keywords 85 giovanni caffio, maurizio unali doi: 10.23738/ccsj.130210 book review: yellow, the history of a color 95 renata pompas 5 color culture and science journal vol. 13 (1) issn 2384-9568 editorial color and pandemic when maurizio rossi asked me to write the editorial of the first 2021 issue, the first thought has been about pandemic. this difficult and strange situation has deeply influenced us all. scaring us, tickling our rebel side, but also in some cases forcing a little bit of meditation. let me humbly share with you some concise questions and thoughts about color and pandemic. please bear with me if they seem out of topic. they aim to be just stimuli to start hopefully broader discussions, color enthusiast is a wide community, i truly hope to see it enlarging even more. color after pandemic what will remain in the field of color after this pandemic? color share with coronavirus the fact that they both need a human to exist. but while the virus is a menace for the host, color is a powerful resource. we all know that color is in the eye of the beholder (more correctly in his/her brain), but we easily forget this fact, treating color as an objective property, external from our visual system. but it is not. thus, let's put back human at the center of our research on color. a well-designed visual experiment worths thousand formulas. color for pandemic beside the color we sense and perceive, color has a strong effect on our body and mind. it is not just a property of what we see, it affects our mental and physical health. the many self-made theories about color need scientific research to assess them. pandemic underlined our weakness; color can support our future strenght. the pandemic of color color research has been fostered for many years by the industries of lighting first, then by the digital printing and recently by the display community. at every step the related business model changed, much faster than major part of scholar's approach. the interest about color is always present, what is changing is the way research is shared and spread and the way industries use it and depends (or not) on it. in a global marked of research and production, standards and rules are less and less shared and maybe necessary. this can be seen as a positive fact since our knowledge about vision and color is still very limited. we are going to face new challenges about education and knowledge sharing and pandemic has been a test bed. pandemic is a nightmare that we can't wait to consider history, but we need to keep what we have learned from it. 6 color culture and science journal vol. 13 (1) issn 2384-9568 so what? a journal is the overall sum of its contributors. if these points raised any comments or further questions, better if controversial, please share with us. they will be the topic of future editorials. hopefully out of this pandemic march, 2021 alessandro rizzi deputy editor ccsj full professor of colorimetry and multimedia università degli studi di milano 38 color culture and science journal vol. 14 (2) doi: 10.23738/ccsj.140205 digital applications to train color ordering in three dimensions for architects and designers juan serra 1 , javier cortina maruenda 1 , ana torres barchino 1 , jorge llopis 1 1 grupo de investigación de color en arquitectura, instituto de restauración del patrimonio, universitat politècnica de valència; juanserra@ega.upv.es, javier.cortinamaruenda@ega.upv.es, atorresb@ega.upv.es, jllopis@ega.upv.es, corresponding author: ; juan serra (juanserra@ega.upv.es) abstract gamification is one of the main motivation and learning strategies of current generations. on the other hand, the study of color from the creation of the bauhaus through the exercises developed by joseph albers has always had an undeniable component of experimentation. motivated by this double idea, from the color in architecture research group we have studied the use of games in the training of architects for color discrimination. among all the games aimed at training colour discrimination, puzzles are probably the most widespread. it is noteworthy that almost all of them use flat geometries, ignoring the fact that colors have three perceptual variables, and the main colour notation systems render 3d solids. it is enough to name munsell or ncs color solids to recognise this spatial variable. so space will be a variable to be taken into account in our study, becoming one of the characteristics more intimately related to the profession of architecture. maybe one of the most important skills that an architect must have is the mastery of spatial vision. in this way, the studio tries to combine gamification, training in colour discrimination and 3d management for architects. keywords architecture, geometry, color order system, gamification, puzzle, app received 30/03/2022; revised 08/08/2022; accepted 11/10/2022 mailto:juanserra@ega.upv.es mailto:jllopis@ega.upv.es mailto:juanserra@ega.upv.es digital applications to train color ordering in three dimensions for architects and designers 39 color culture and science journal vol. 14 (2) doi: 10.23738/ccsj.140205 1. introduction in the acquisition of skills to work with the color for an architect or an interior designer, it is important to train the visual discrimination of colors and to gain the sensitivity to display different colors in order. both learnings are on the roots of the different color curricula in the architecture schools since the beginning of the xxth century and are considered essential knowledge. gamification demonstrates to be a good way of involving students in the acquisition of these skills that not only need a rational understanding of color theory, but also need to be naturally integrated as an instinctive skill, something that happens after a dedicated training. among all the types of games used for learning, digital color puzzles are good alternatives to train these abilities. but it is noteworthy that, despite having color three perceptual variables, most of the available color puzzles keep working with just two dimensions of color. for this reason, the app colordoku 3d, aims to ease the understanding that color has three perceptual variables, and to train the visual discrimination of these variables. the app also gives the opportunity to get familiar with interesting and difficult to understand polyhedron. 2. the teaching of color order systems in architecture curricula the description of color as a visual phenomenon with three perceptual variables, hue, value and saturation, allowed the proposition of different three-dimensional models since the beginning of the xixth century, with different shapes depending on the arrangement of the fundamental colors and specific nomenclatures for the variables. the time for using linear systems or two-dimensional diagrams such as the ones developed by goethe in his theory of colors (1810) or by neewton in his chromatic circle (1704) is far behind us. at present, among all the three-dimensional models, two are the most popular for art and design: the munsell color system, and the natural color system (ncs) [1]. at the munsell color system, colors are identified by three parameters, hue, value and chroma. with this data, you can obtain the coordinates of any color in the munsell solid. color solid has an irregular three dimensional shape as a consequence of this system based in visual color perception. on the other hand, the structure of the ncs color solid is based in three pairs of opponent colors: white-black, green-red and yellow-blue. its geometry is a regular symmetric double cone (nemcsis and caivano 2015) (figure 1). figure 1: the ncs natural color system (the natural colour system is the copyright and trademark property of ncs colour ab) (1979) by anders hård and lars sivik. the ability to discriminate colors and organize them in the right order is a worth training for architects and artists, as it improves their sensitivity and expands their color abilities. for these reasons, almost all the modern color curricula for architects included the study of color circles and other similar organizations of colors with a certain logic (hirschler et al. 2018). this was also the case of the basic courses at the bauhaus dessau and the hochschule für gestaltung ulm, with important academics such as albers, itten, maldonado, etc. later on, annie and joseph albers kept training students in color skills with interesting experiences at the black mountain college innorth carolina (tóth, molnár and kárpáti 2021, campos and moya 2021). in recent years, some of the traditional color exercises shifted into a digital version, as it happened with the perennial interaction of color by joseph albers (franco taboada 2015). this book has been developed as an ipad application, surpassing the original format in content. this app published by yale university press has been widely awarded and recognized (figure 2). nevertheless, some of these traditional exercises need personal involvement, are time-consuming, and not always are easy for generations of students and professionals that are becoming more impatient and less persistent. when waiting has become an intolerable matter, the impatience syndrome appears. this syndrome affects not only the current generation of students but seems to extend to future generations (bauman 2015). at the same time, in a completely digitalized society, gamification gives an opportunity to improve the color skills, and the pleasure of organizing colors in order is on the roots of a big number of digital games: blendoku (lonely few 2015), chroma rush (lonely few 2017), i love hue (zut 2017), blendoku 2 (lonely few 2019), chromatic: color puzzles (2019), tinge: a color game (suwao llc 2019), chroma (noisy duck 2021), i love hue too (2021), etc. gamification is the use of nondigital applications to train color ordering in three dimensions for architects and designers 40 color culture and science journal vol. 14 (2) doi: 10.23738/ccsj.140205 game-in-context game mechanics, elements, and design techniques to engage users and solve problems (zichermann & cunningham, 2011; werbach & hunter, 2012). in general, this type of game provides a series of colours to be included in an incomplete two-dimensional pattern. the patterns used in these games are usually simple rows and columns of colour gradations, like in the game blendoku. in this case the difficulty level increases with the inclusion of more pieces to place in the puzzle, and having a smaller chromatic variation. in the case of i love hue too, the puzzles are based on complex mosaics and the level difficulty level increase, as in the other games, with the number of colors to fill, and the geometry complexity. as indicated, all these apps have a two-dimensional interface and forget that color is a three-dimensional perceptual phenomenon. nevertheless, the spatial representation of colors with their three perceptual variables results in some non-regular solids like spheroids, cylinders, double cones and many other geometries depending on the color system used. being most of them not regular bodies, the colour discrimination learning can benefit from using three dimensional solids, as well as the understanding of complex regular bodies can be boosted by playing with the three variables of colors. for all these reasons, a puzzle in three dimensions to order colors onto regular bodies might be beneficial for architecture students. figure 2: interaction of color, is a digital version of the traditional exercises of j. albers in a digital way. 3. the teaching of regular bodies in architecture curricula to have a robust spatial imagination is an essential skill for an architect, and so it is the understanding and manipulation of three-dimensional objects. if we review the european history of architecture, this ability has traditionally been cultivated with the study of regular polyhedra with complex geometries that we find since the most important treatises of geometry belonging to the renaissance period. even today we can find the study, drawing and analysis of these geometries forming a fundamental part of the theoretical “corpus” of graphic expression subjects. books as beyond the cube: the architecture of space frames and polyhedra by jeanfrançois gabriel (1997), continue to maintain the interest and relationship between polyhedrons and architecture. works of louis kahn (1910-1974), buckminster fuller (1895-1983) and philip johnson (1906-2005), among other, are a clear example of this idea. one of the fundamental and first books that study and analyse this subject it’s the de divina proportione (1509) written by the mathematician luca pacioli and illustrated by leonardo da vinci. this mathematical treatise praises mathematics as the basis of science and architecture. the book contains a small section on architecture, but undoubtedly one of its main assets is the study of regular polyhedra. these polyhedra are represented using the most cutting edged graphic resources of that period to help in the understanding of digital applications to train color ordering in three dimensions for architects and designers 41 color culture and science journal vol. 14 (2) doi: 10.23738/ccsj.140205 its geometries. by alternating the drawing of solid geometries and solids represented in wire frame in more than 60 draws, it was possible an easy distinction between front and back edges, (figure 3a). figure 3: a) representation of an icosahedron, ycocedron planus vacuus, by leonardo da vinci for de divina proportione (luca pacioli, 1509); b) oliver byrne, the first six book of the elements of euclid, london, 1847. book i prop. xxxvii "triangles on the same base and between the same parallels are equal". in the xixth century, the color was also used as a graphic resource for a better understanding of geometry. this is the case of the founding text of geometry the elements (στοιχεῖα) written by euclides (325-265 bc), that was reedited by oliver byrne in 1847 with graphical codes of colors replacing the original text. as the same byrne wrote in his foreword “we do not introduce colour for the purpose of entertainment, or to amuse by certain combinatios of tint and form, but to assist the mind in its researches after truth, to increase the facilities of instruction, and to diffuse permanent knowledge” (byrne 1847, quoted in higón-calvet 2013). the combination of colors and geometry resulted in a very beautiful and easy to understand publication (figure 3b). nowadays, as we have already explained, as it has happened with other colour-related knowledge, the videos and animated graphics with continuous movement seem to be the most adequate means of expression to explain and understand geometries, with interesting websites explaining geometric concepts in three dimensions. [2] 4. description of the app colordoku 3d to merge the knowledge about regular bodies and color understanding, a group of academics and students developed a digital app called colordoku 3d, that is available for free at the web page of the color research group in architecture upv. [3] by the moment, it contains four regular solids with triangular faces: icosahedron (20 triangular faces), triacysthetrahedron (12 triangular faces), tetrahexahedron (24 triangular faces) and hexaquisocta-hedron (48 triangular faces) (figure 4). the icosahedron is a polyhedron that belongs to the platonic solids, and has been widely represented and used since antiquity. platonic solids are those that have all faces equal and are a regular polygon. there are only five, for this app we choose the only one that represented a certain complexity for the game. the other three polyhedra belong to the family of catalan solids. these polyhedra were published in 1865 for the first time by the belgian mathematician eugène charles catalan after whom they are named. there are only thirteen and are generated with two archimedes solids. so, their faces have irregular polygons but equal dihedric angles. this type of polyhedra, besides being part of the basic teaching in architecture for the control of geometry, has also had practical applications in the use of vaults (mallo 2013). we chose for the puzzle the triacysthetrahedron, tetrahexahedron and hexaquisoctahedron. these solids have faces with triangular bases, so they were more suitable for programming. the triacysthetrahedron is a truncated tetrahedron, the tetrahexahedron is a truncated octahedron and the hexaquisoctahedron is a truncated cuboctahedron. figure 4: the four regular bodies implemented in colordoku 3d: a) icosahedron, b) triacysthetrahedron, c) tetrahexahedron and d) hexaquisoctahedron. digital applications to train color ordering in three dimensions for architects and designers 42 color culture and science journal vol. 14 (2) doi: 10.23738/ccsj.140205 figure 5: view of the research group's website (gica). application login screen. https://grupocolor.webs.upv.es/?page_id=3021 figure 6: interface of colorduku 3d with an uncompleted puzzle of an icosahedron. in the initial screen of the app, users can choose between the four aforementioned polyhedra, and set different parameters depending on the expected level of difficulty for the game, such as the scale of the solid, its position inside the color space, and the number of faces of the figure that will appear with the colors already set. with this information, a color palette is displayed and the 3d puzzle is launched. turning the figure round in any direction and increasing its size if needed, users can drag and drop the colors provided in the color palette into the right faces of the solid to complete the 3d puzzle. the level of difficulty increases with the number of faces of the selected solid and with the scale of the selected solid. the difficulty is directly proportional to the number of faces and inversely proportional to the scale of the chosen solid. in the screen of the settings, and when the scale of the regular body is under 100%, it is possible to place it in different positions inside a virtual cube. this cube represents the color space hsl (hue, saturation, lightness), which is an alternative model to rgb, and therefore a useful color space for digital displays. when the user selects different values between 0% and 100% for the three spatial directions x, y and z, is placing the solid in a different position into the hsl space. the app will automatically generate a color palette assigning to each triangular face of the solid the color corresponding to the barycenter of such a face in the hsl model. when the 3d puzzle is launched, the interface is divided into two parts (figure 6). on the left side there is a color palette with all the colors of the puzzle in a random order, and on the right side the user can rotate and scale the solid. those colors preset have a grey cross on the color palette and a black dot on the corresponding face to indicate that they are locked. the rest of the colors in the color palette can be dragged and dropped onto the corresponding faces. with the digital applications to train color ordering in three dimensions for architects and designers 43 color culture and science journal vol. 14 (2) doi: 10.23738/ccsj.140205 help of an eraser, the user can remove a color placed in a wrong position that will automatically move back to the color palette. when the 3d puzzle is correctly completed the indication “puzzle completed” appears. we hope that this new app will help to improve at the same time the perceptual color discrimination ability together with the spatial vision. 5. results and conclusions durint the 2020/21 course we invited the students enrolled in the subject graphic and chromatic design of the master in architecture of the upv to train with colordoku 3d and give their opinion. a total of 18 students (12 females, 6 males; mean age= 23) played with the app for a couple of days and gave feedback via an online questionnaire. regarding the selection of the polyhedra, icosahedron was the most selected (50%), followed by tetrahexahedron (27.8%), hexaquisoctahedron (16.7%) and triacysthetra-hedron (5.6%), therefore the selection of the polyhedra seemed to be rooted in a personal attachment and not in the number of faces of the solid or its difficulty. according to the answers, 33.3% of the respondents considered the random colors combination provided beautiful, 22.2% not beautiful and 44.4% indifferent. considering the difficulty of the 3d puzzle, 44.4% considered it easy, 33.3% intermediate and 21.7% difficult or very difficult, with this assessment dependent on the puzzle settings of each participant. in an informal interview in the classroom, students expressed their interest in the app, indicating that it was fun and engaging, but also pointing out some aspects to improve, particularly related with the interface and the general user-friendliness of the app. students seemed to be in favor of having an automatic preset of the parameter of the puzzle. we conclude that colordoku 3d can be a useful tool for the education of students in the improvement of their perceptual color discrimination ability and spatial vision, being a complementary resource to train their color abilities out of the classroom via gamification. in the future, the app will need some upgrades to make it more user-friendly and engaging, considering the information provided by a target group of users. in future developments, it will be important to have more evidences to evaluate the improvement of knowledge of solids and colors after training with colorduku 3d. 6. acknowledgements we want to acknowledge david de andrés that belongs to the itaca group, universitat politècnica de valència for and irene cebrián onsurbe and her work in the technical development of colordoku 3d. 7. conflict of interest declaration the autors declare that they have not actual or potencial conflict of interest including financial, personal, or other relationships with other people or organizations within three years of beginning the submitted work that could inappropriately influence, or be perceived to influence, their work. 8. funding source declaration all authors declare that the investigation has not been supported or paid by any funding sources or research grants 9. authors short biography juan serra lluch phd architect, full-time professor and subdirector of research in the school of architecture of valencia. member of the color research group of the heritage restoration institute of the universitat poltècnica de valència, with expertise in color in modern and contemporary architecture. author of numerous papers and the textbook color for architects (papress, 2019). javier cortina maruenda phd architect, full-time professor and member of the color research group of the heritage restoration institute of the universitat poltècnica de valència. ana torres barchino phd in fine arts from the universitat politècnica de valència. professor in the graphic expression department in the upv. degree in master in conservation and restoration of architectural and urban heritage by the polytechnic university of madrid. her research lines are focused on the analysis of colour in architectural heritage and design. jorge llopis. phd. architect and full professor at the universitat politècnica de valència in the graphic expression department. his research lines are focused on the analysis of documentary and cartographic information on architectural heritage and on the study of new architectural graphic strategies after the arrival of digital drawing. notes [1] there are many other systems for ordering colours in a threedimensional space organised by three perceptual variables. among digital applications to train color ordering in three dimensions for architects and designers 44 color culture and science journal vol. 14 (2) doi: 10.23738/ccsj.140205 them, the coloroid system developed by nemecsis between 1962 and 1980 stands out. this system uses hue as an angular coordinate, saturation as a radial coordinate and luminosity as a vertical coordinate. [2] http://www.matematicasvisuales.com/index.html [3] https://grupocolor.webs.upv.es/ licensing terms articles published in the “cultura e scienza del colore color culture and science" journal are open access articles, distributed under the terms and conditions of the creative commons attribution license (cc by). you are free to share (copy and redistribute the material in any medium or format) and adapt (remix, transform, and build upon the material for any purpose, even commercially, under the following terms: you must give appropriate credit to authors, provide a link to the license, and indicate if changes were made. you may do so in any reasonable manner, but not in any way that suggests the licensor endorses you or your use, you may not apply legal terms or technological measures that legally restrict others from doing anything the license permits. the authors keep the rights to further publish their contents where they want and can archive pre-print and post-print (submitted version and accepted version) and the published version of the pdf of their article with no embargo period. references bauman, z. (2005). los retos de la educación en la modernidad líquida. barcelona, spain: gedisa editorial. fernández-campos, a.l. and sánchez-moya, m.d. (2021). “tono vs. código: el color en el curso básico de la hochschule für gestaltung ulm”, ega expresión gráfica arquitectónica, 26 (41), pp. 178–89. https://doi.org/10.4995/ega.2021.14036. franco-taboada, j.a. (2015). “from goethe’s theory of colours to albers’ interaction of colour”, ega revista de expresión gráfica arquitectónica, 20 (25), pp. 48–55. https://doi.org/10.4995/ega.2015.3703. gabriel, j. f. (1997). beyond the cube: the architecture of space frames and polyhedra. john wiley & sons higón-calvet, j.l. (2013). “the use of colour as a way for the understanding of the geometry. the edition of euclid’s elements by oliver byrne. london 1847,” in garcía-codoñer, a. (ed.) x congreso nacional del color sedo. valencia, spain: universitat politècnica de valència, pp. 424–25. hirschler, r., csillag, p., manyé, p. and neder, m. (2018). "how much colour science is not too much?”, color research and application, 43 (6), pp. 977–92. https://doi.org/10.1002/col.22275. mallo, m. (2013). “un viaje por geometrías encontradas, descubiertas, redescubiertas o reinterpretadas” in architecture, education and society. international workshop. barcelona, pp. 29-31. nemcsis, a., and caivano, j.l. (2015). “color order systems.” in ronnier-luo, m. (ed.), encyclopedia of color science and technology. new york: springer. https://doi.org/10.1007/9783-642-27851-8. tóth, a., molnár, g., and kárpáti, a. (2021). “learning about colour – the legacy of the bauhaus masters”, international journal of art & design education, 40 (1), pp. 108-125. https://doi.org/10.1111/jade.12338. werbach, k., and hunter, d. (2012). for the win: how game thinking can revolutionize your business. pennsylvania, usa: wharton digital press. zichermann, g., and cunningham, c. (2011). gamification by design: implementing game mechanics in web and mobile apps. sebastopol, usa: o’reilly media. http://www.matematicasvisuales.com/index.html https://grupocolor.webs.upv.es/ https://doi.org/10.4995/ega.2021.14036 https://doi.org/10.4995/ega.2015.3703 https://doi.org/10.1002/col.22275 https://doi.org/10.1007/978-%203-642-27851-8 https://doi.org/10.1111/jade.12338 7 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140101 the flexichrome: visual examination and scientific analysis of an overlooked color process. nayla maaruf, sylvie pénichon, maria kokkori the art institute chicago, 111 s. michigan ave, chicago, il 60603, u.s.a corresponding author: nayla maaruf (nmaaruf@artic.edu) abstract flexichrome is the commercial name for a dye imbibition process where the color image is formed by hand coloring a gelatin relief with acid dyes, without the use of color separation negatives and with great creative freedom. final prints resemble those made with other processes like carbro or hand-colored gelatin silver. the flexichrome was first marketed by jack crawford as the ‘crawford flexichrome’ in the early 1940s. kodak purchased the patent from crawford and remarketed the product as the ‘kodak flexichrome’ from 1949 until 1961. this paper presents an overview of the flexichrome process and, through the study of selected flexichrome prints and historic dyes, investigates the technology and variations in the formulations available. prints and dye samples were characterized using a complement of analytical techniques including visible and fluorescence light microscopy (vlm, flm), fourier transform infrared (ftir) spectroscopy, and x-ray fluorescence (xrf) spectroscopy. a key goal of the study was to establish identification clues for flexichromes, informed by results from invasive and non-invasive analytical techniques. handheld xrf analysis showed both the absence of silver and chromium, supporting the ability to distinguish a hand colored gelatin silver print and carbro prints from the flexichrome. unaided visual examination and vlm provided the following visible characteristics specific to the flexichrome: continuous tone with no misalignment or misregistration of superimposed color layers and the presence of fluid lines and visible brushstrokes depending on the skill of the colorist. a print can also exhibit differential gloss and fluorescence in the magenta colors when unobstructed by a finishing layer. ftir analysis of multiple sets of dyes confirmed the nature of the dyes as being acid dyes as indicated in the literature. color fading is therefore not uncommon in contrast to carbros which have a higher lightfastness. keywords: color photography, photographic identification, materials analysis, flexichrome, dye imbibition. received 31/07/2021; revised 11/11/2021; accepted 28/12/2021 the flexichrome: visual examination and scientific analysis of an overlooked color process. 8 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140101 1. introduction the flexichrome (a dye imbibition process) is a photographic color process that has received limited attention in the historical and conservation literature (sipley, 1951; coe, 1978; koshofer, 1981; pénichon, 2013). it was however used by a wide range of photographers; from commercial, to artistic and novelty use. in the words of its inventor jack crawford, flexichrome compared “favorably in quality with washoff relief, chromatone, and carbro,” [1] and was “quite similar to the latter method in texture and physical appearance” (crawford, c.1939). making a print with the flexichrome was cheaper and faster than with other color processes available at the time; the process was praised for its color flexibility and high-quality color images hence its name ‘flexichrome’. it clearly offered certain advantages, including the use of a regular black-and-white negative and the relative simplicity of the process. it takes, however, a significant number of steps and materials to create a flexichrome. although the process was widely distributed by eastman kodak when it relaunched it in 1949 (kodakery, 1949; australasia photo-review, 1949; austin american, 1949), it was soon overshadowed by chromogenic processes and eventually taken off the market by kodak. figure 1: herbert lyman emerson, untitled, 1950's, flexichrome, 37.1 × 49.2 cm (image); 37.9 × 50.2 cm (paper), photography and media, 2012.282, the art institute of chicago. courtesy of the art institute of chicago. this paper will highlight the historical development of the process and visual characteristics of the flexichrome based on a print by herbert lyman emerson in the collection of the art institute of chicago (figure 1) and reference prints from the image permanence institute (ipi) and private collections. secondly, we will report on findings of analysis performed on prints and sets of crawford and kodak original dyes, including visible and fluorescence light microscopy (vlm, flm), fourier transform infrared (ftir) spectroscopy, and x-ray fluorescence (xrf) spectroscopy. 2. history of the flexichrome process 2.1 the crawford flexichrome (1940-1942) in 1938 jack crawford, a new york photographer, filed a patent application for a new method of producing multicolored relief pictures (crawford, 1941b). the following year, he filed a second patent with minor chemical changes to the process (crawford, 1943). the patents describe the act of coloring a gelatin relief by hand to create a color photograph, and contain limited material information. the receiving layer is described as a gelatin silver bromide film in the first patent, and a ‘wash-off relief emulsion’ in the second one. while crawford did not invent a new color photographic process, he creatively used the existing materials and knowledge of dye imbibition photography to make his own color prints from black-and-white negatives. his method eliminated the need for separation negatives, which were the more complicated aspect of the carbro and wash-off relief processes. the crawford flexichrome was brought to the market in 1940 by the defender photo supply company, an early leader in the manufacture of photographic materials located in rochester, new york (potter, 1940)[2]. photographers could purchase crawford flexichrome materials individually or as a kit through the crawford flexichrome company, defender or select dealers—$6 for the complete outfit (deschin, 1941) (figure 2). crawford promoted his process in popular magazines such as photo technique, minicam, the camera and the complete photographer (dudley, 1940; crawford, 1941a, 1942b, 1942a), and organized public demonstrations at various locations around the united states (nevada state journal, 1941; new york times, 1941e; new york times, 1941d) [3]. for those who wanted to color their own pictures but did not care to make the black-and-white flexichrome print (i.e. the gelatin relief), crawford flexichrome laboratories in new york city offered a printing service. customers supplied original negatives, prints, or transparencies and size desired; they received their prints in the mail, ready to be colored (crawford, 1941c). by 1941, the crawford flexichrome company was busy enough to be looking for more employees to help cover the demand (new york the flexichrome: visual examination and scientific analysis of an overlooked color process. 9 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140101 times, 1941a; new york times, 1941b; new york times, 1941c). commercial success was however short-lived. defender photo supply company ended its collaboration with crawford in 1942, when the united states entered the second world war and supply for commercial use was deprioritized over military needs (defender trade bulletin, 1942; coe, 1978; nadeau, 1989). between the years 1942 and 1949, the authors could not find ads or articles on the flexichrome, suggesting the product was commercially unavailable until it was re-introduced by the eastman kodak company in 1949 as the ‘kodak flexichrome process’. by 1943, jack crawford had sold his patents to kodak; he eventually moved to rochester, to direct the company’s flexichrome studio and improve the process (crawford, 1943; kodakery, 1949; lipton, 1949). figure 2: a crawford flexichrome kit comprised of a set of 11 flexichrome colors, a reducer and a modeling agent (or black dye), a jar of liquid paper backing, a bottle of flexilene quick drying varnish, chromic acid, ammonium dichromate, two brushes, lint-less paper blotter and an instruction booklet. film and processing chemicals were purchased separately (crawford, 1940). courtesy of the george eastman museum. 2.2 the kodak flexichrome (1949-1961) it was common practice of the eastman kodak company to acquire promising photographic patents and hire their inventors to continue their work under the kodak brand. the company had the resources to support research and development of the flexichrome and the ability to advertise and market the product globally. it developed an entire new line of kodak flexichrome products with simplified ready-to-use sets of chemicals and instructions, an improved convenience over crawford’s system where customers had to make the processing chemicals from scratch (eastman kodak company, 1949). in 1949, an extensive marketing campaign for the new kodak flexichrome began worldwide. kodak emphasized the ease of making a color print using this process. the product was first introduced in new york city to commercial and professional photographers, dealers, artists, illustrators, and advertising agency representatives with an exhibit, a movie and demonstrations (kodak, 1949) (figure 3). figure 3: jack crawford at the launch event of the new kodak flexichrome (kodakery, 1949). the flexichrome process was suitable to a myriad of uses, from studio portraiture to popular baseball cards, medical photography or artistic production. commercial photographers such as herbert lyman emerson likely used the process because it lent itself well to the production of originals that would be reproduced in magazines, while artists like lyman grey fayman or josep masana created dramatic images of great artistic value (la jolla museum of art, 1969; galmes, 1984). in the industry, textile manufacturers, for example, favored the flexichrome process for the illustration of their products because they could obtain closer matches to the colors of their original subjects than with other color processes available at the time (varden, 1967). kodak discontinued the kodak flexichrome in 1961 but the dyes remained available until stock lasted (nadeau, 1989). they were later marketed as kodak retouching colors for color prints and transparencies and were especially well suited to retouch dye imbibition prints (varden, 1967). the flexichrome: visual examination and scientific analysis of an overlooked color process. 10 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140101 3. how to make a flexichrome the flexichrome is a dye imbibition process. this means it uses the properties of a colloidal receiving layer to absorb or imbibe acid dyes and form a full color image. making dye imbibition prints usually consists of successively transferring dyes from a yellow-, magenta and cyan-dyed relief matrix onto a receiving sheet of paper coated with gelatin. with the flexichrome, dyes are applied directly by hand onto a single positive gelatin relief image. 3.1 making a gelatin relief the making of a flexichrome print started with a blackand-white negative, obtained directly in the camera or made from a color transparency. the negative was printed onto a sheet of flexichrome film by projection or contact; exposure was performed through the film base (dudley, 1940; crawford, 1941a). crawford flexichrome film, with a semi-matte surfaced celluloid base, was available in sizes from 5×7 inches to 20×24 inches (crawford, 1941a; lester, 1942; deschin, 1941). film in rolls 42 inches wide and 10 or 25 feet long was also available, for photomurals or commercial display (crawford, 1941b; crawford, 1942). likewise, kodak flexichrome stripping film came in sizes from 5×7 to 20×24 inches and in rolls of 20 inches by 30 feet or 40 inches by 30 feet (eastman kodak company, 1950). once exposed, the film was developed and then tanned in a dichromated solution to harden the gelatin surrounding the developed silver image. at that point, the film was immersed in warm water to wash away the unhardened or unexposed soft gelatin and create a relief where areas of thick gelatin correspond to the dark areas of the image. next, the relief was bleached, fixed, and washed to eliminate its silver content [3]. the last step before coloring consisted in dying the relief in a black or ‘modeling’ dye bath. the gelatin relief absorbed the dye in proportion to its thickness resulting in a positive black-and-white image on a clear film base, which would be the outline to guide in the coloring of the image. with crawford flexichrome, an opaque white paint or ‘liquid paper’ was applied to the back of the film to create a print. with kodak flexichrome, the dyed gelatin relief was stripped from its base and transferred onto a paper substrate [4]. 3.2 coloring the gelatin relief the gelatin relief was then ready for coloring. during coloring, the dyes were absorbed by the gelatin proportionally to its thickness, i.e. the density of the image. each new application of color displaced a portion of the black modeling dye. dyes could be applied at will, until the desired color had been reached. each print created was unique; multiple copies of an image required the printing and coloring of new reliefs (figure 4). figure 4: the process of hand coloring a kodak flexichrome (eastman kodak company, 1950, pp. 2021). 4. general visual characteristics of a flexichrome examples of flexichrome prints and transparencies are not easy to find per se, partly because in many cases they might have been misidentified as carbro or hand-tinted photographs (maaruf, 2021). key characteristics of flexichrome prints are as follows: firstly, the color is distributed in a continuous tone, this means there is no delineation between color areas, and the shading or color transition is smooth. secondly, because the colors of flexichrome prints are applied by hand with a brush, there is no misregistration or misalignment of color layers, contrary to color prints made with assembly processes such as dye imbibition or carbro. depending on the skill of the colorist, the edges of colored areas might not display crisp color delineations, but rather fluid lines that sometimes overlap or run into each other (figure 5). fine brushstrokes are usually visible in areas such as the eyelashes or lips (figure 6). these brushstrokes can be confused with retouching but upon close inspection, it should be clear that the color is part of the gelatin layer. when examined in specular light, flexichrome prints typically display a differential gloss between light and dark areas of the image. the high-density or dark areas— where the gelatin layer is thicker—are glossier than the low-density or light areas of the image—where the gelatin is thinner. the differential gloss might not be visible if the print has received a thick application of varnish. the flexichrome: visual examination and scientific analysis of an overlooked color process. 11 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140101 figure 5: detail of emerson, untitled, showing continuous tone and no delineation between color areas. courtesy of the art institute of chicago. figure 6: detail of emerson, untitled, showing brushstroke color application visible in the detailed areas. courtesy of the art institute of chicago. under ultra-violet radiation, containers of magenta, red, and yellow reference dyes as well as the reducer fluoresced. fluorescence in a print will however depend on the amount of dye present, the mixture of the dyes and the possible obstruction of a finishing varnish application. in addition, the authors observed fading in several reference prints that had most likely been kept in frames and on view for an extended period of time. it would be worth investigating the light fastness of the flexichrome dyes to inform display guidelines. 5. analysis 5.1 x-ray fluorescence (xrf) spectroscopy xrf analysis was performed on six kodak flexichromes: the emerson print at the art institute, two reference prints from the ipi, and three prints from a private collection. two carbro prints were also analyzed to provide comparative spectra. no silver (ag) was detected in the flexichrome prints, which confirms that the ag has been bleached out to the extent that it is not detectable with handheld xrf. this provides the ability to distinguish a hand-colored gelatin silver print from a flexichrome [5]. additionally, the elemental compositions of carbro and flexichrome prints were compared, due to the visual similarities between these two types of print. both processes make use of a dichromate to harden the gelatin and create a relief; however, chromium (cr) was only detected by handheld xrf in the carbro prints but not in the flexichromes (figure 7). based on these analyses, the absence of both ag and cr appears to be an analytical marker for the flexichrome, corroborating information derived from visual comparisons. handheld xrf is limited in its ability to detect certain elements. the absence of both ag and cr in the xrf spectra does not mean they are not in any amount present in the prints, it only indicates that the amounts are non-detectable using this technique. 5.2 fourier transform infrared (ftir) spectroscopy ftir was used in the analysis of a set of crawford flexichrome dyes from the george eastman museum collection and three reference sets of kodak flexichrome dyes acquired for this project. the crawford set contains a group of 12 dyes comprising blue, blue green, green, black, brown, flesh, lemon yellow, primary yellow, orange, red, scarlet, and violet. two reference kodak sets contain a slightly different group of 10 dyes (blue, cyan, brown, flesh basic, neutral, green, magenta, orange, purple, red, and yellow) and the third set contains 8 dyes (omitting the orange and purple). according to contemporary sources, there were material differences between the iterations of the flexichrome. between the first and second patent by crawford for example, there was a change in chemical processing of the prints, and meeting notes from the kodak research laboratories made between 1947 and 1952 show a constant evolution in material composition to improve the tinting strength of dyes and lightfastness (condax papers, 1947, 1950-1952). while production of dyes was curtailed in the united states during world war ii, the dyestuff industry expanded rapidly in the postwar years and kodak research laboratories continued their explorations and embraced advances in technology. the flexichrome: visual examination and scientific analysis of an overlooked color process. 12 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140101 figure 7: xrf spectra of a reference carbro (red) and a kodak flexichrome (green). ”only 4 or 5 dyes will be necessary to cover all the range of colors needed,” wrote kodak researcher louis condax in his meeting notes, ”however, mr. crawford feels that the mixtures should be incorporated in the set rather than to have the user mix them.” (condax papers, 1947). the dyes used for dye imbibition processes fall under the family of acid dyes, which belong to the larger class of synthetic organic dyes (colton and thronson, 1940). the spectra collected from the crawford dyes indicated the presence of acidand azo-dyes. the spectra collected from the three kodak sets showed close similarities to each other and, as suggested in the condax papers, of the analyzed reference dyes there were only a few main types and the rest were mixtures of blue, magenta or red, and yellow dyes. analysis indicated the presence of phthalocyanine blues, azo yellows, alizarin and anthraquinone reds (figure 8 & figure 9). figure 8: infrared spectrum of crawford flexichrome primary yellow dye (blue) compared with the irug reference spectrum iod00031 of acid yellow 23 (black). figure 9: infrared spectrum of kodak flexichrome green dye (blue) compared with the irug reference spectrum iod00043 of acid green 6 (black). ftir was therefore useful for gaining information about the chemical classes of the flexichrome dyes. there are often only minor chemical differences between individual colorants within the class, which, along with the presence of binders and extenders, complicates interpretation of the spectra (lomax, schilling and learner, 2007). therefore, complementary analytical techniques are required for a more definitive identification of these materials. this will also contribute to investigate further their lightfastness. 5.3 cross-section in collaboration with ipi, cross-sections were prepared to further understand the structure of flexichrome prints. a sample from a kodak print shows a paper substrate with a baryta layer and a gelatin coating on top, most likely a sheet of kodak dye transfer paper, recommended by kodak in the user manual. above the gelatin layer of the the flexichrome: visual examination and scientific analysis of an overlooked color process. 13 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140101 paper substrate is the gelatin relief with imbibed dyes. the cross section shows that the coloring dyes did not penetrate all the way through the relief layer and that a portion of the modeling black dye is still present. finally, there is the surface varnish layer (figure 10). this correlates with the cross-section diagram published in the kodak material data series (figure 11), although the varnish and baryta layers are absent in the diagram (eastman kodak company, 1950). together with xrf analysis and a close visual assessment, cross-sections can provide additional information. however, taking a cross-section is a destructive method and is not advised on collection items. the paper base and baryta layer may not be present in the cross-section if the relief was transferred onto a different substrate. the layering structure of a crawford flexichrome will consist of a bottom paint layer—unless it is a transparency—followed by a celluloid layer, the gelatin relief with imbibed dyes, and a final varnish. figure 10: cross-section of a flexichrome in transmitted light. [1] varnish, [2] dyed gelatin relief, [3] gelatin coating, [4] baryta, [5] paper support. courtesy of the image permanence institute, rochester institute of technology. figure 11: cross-sectional diagram of a flexichrome print, showing relief image greatly magnified (eastman kodak company, 1950, pp. 22-23). 6. conclusion the flexichrome process is a dye imbibition process that might be more prevalent in photographic collections than initially considered. flexichrome prints share visual characteristics with carbro and hand-tinted gelatin silver prints, which has sometimes led to their misidentification. due to misidentification and a lack of coverage in the historic and contemporary literature, the process is easily overlooked, even though it seems to have found commercial success under the kodak branding, and was accessible and distributed worldwide. visual characteristics of a flexichrome include a continuous tone, a lack of misregistration or misalignment of color layers, a brushed application of color, and nondelineated color transitions. there is the possibility of overall color fading and of uv-fluorescence of certain dyes. however, the mixing of colors and possible finishing layers may obstruct the fluorescence of the dyes. lastly, because the final product is a gelatin relief, there is the possibility of differential gloss, which might not be detectable if a thick layer of varnish is present. a crawford flexichrome will be identifiable by its painted celluloid support. xrf analysis indicated that silver and chromium were not present at detectable levels in a flexichrome print. elemental analysis complements the visual identification of the process, helping to distinguish it from a handcolored gelatin silver print or a carbro. ftir supported the available literature by showing the dyes belong to the family of acid dyes. the dye sets were found to comprise of mixtures of a limited number of dyes. due to the presence of additives and filler in the dye sets, complementary analysis is needed to further specify the individual dyes. 7. conflict of interest declaration the authors declare there is no conflict of interest concerning the research presented in this paper. 8. funding source declaration funding for this project was provided by the karen and jim frank conservation research fund and the andrew w. mellon foundation. 9. acknowledgment for this research we received significant support from al carver-kubik at the image permanence institute, rochester institute of technology, rochester, ny, and the flexichrome: visual examination and scientific analysis of an overlooked color process. 14 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140101 from erin fischer, taina meller and sarah casto at the george eastman museum, rochester, ny. we would also like to thank art kaplan at the getty conservation institute, los angeles, ca, marla misunas and roberta piantavigna at sfmoma, san francisco, ca, and our colleagues at the art institute of chicago: robert lifson, ken sutherland and jann trujillo. 10. short biography of the authors nayla maaruf andrew w. mellon fellow in photograph conservation at the art institute of chicago, il. she received her ba in conservation of paper-based materials at the university of antwerp and the bern university of applied sciences and her ma in conservation of library and archival materials from west dean college. sylvie pénichon director of photography and media conservation at the art institute of chicago. she received her ma in history of art and archaeology and her advanced certificate in art conservation from the institute of fine arts, new york university. she is the author of twentieth-century color photographs: identification and care (2013), a comprehensive guide to understanding color photographs. she has contributed scholarship to exhibition catalogues andré kertész: postcards from paris (2021) and moholy-nagy: future present (2016), among other publications. maria kokkori associate conservation scientist at the art institute of chicago and visiting professor at the university of chicago. she received her phd from the courtauld institute of art in london and completed postdoctoral fellowships at the courtauld institute and museum of modern art in new york. her research and teaching focus on early twentieth-century european art, the materiality of art, and the intersections among art, science and technology. notes [1] wash-off relief was a dye imbibition process manufactured by the eastman kodak company between 1935 and 1947. chromatone was a silver toning process of the defender photo supply company, marketed from 1935 until 1942. the carbro process is a three-color pigment process where stacked layers of magenta-, yellowand cyan-pigmented gelatin reliefs create a full color image. [2] defender and crawford first exhibited the process in chicago at the combined photographic industry and trade show, august 19-23, 1940 (defender trade bulletin, 1940, new york times, 1941d). [3] if a transparency was desired, the silver image was not bleached, to add density for the viewing in transmitted light or projection. [4] kodak recommended the use of kodak dye transfer paper. however, the gelatin relief could be transferred to any type of paper or any other type of support desired. [5] does not apply to transparencies. experimental 1. visible and fluorescence light microscopy print samples prepared as cross sections were examined using a zeiss axioplan 2 research microscope with reflected light and uv fluorescence illumination; images were captured using a zeiss axiocam mrc5 digital camera. 2. x-ray fluorescence spectroscopy a bruker/keymaster tracer iii-v handheld xrf spectrometer with rhodium tube was used with voltage of 45kv and tunable beam current of 2-25µa. 3. fourier transform infrared spectroscopy a bruker tensor 27 ftir spectrophotometer coupled to hyperion 2000 automated ftir microscope with nitrogencooled broadband mct detector (covering the range 4000–450 cm-1) was used. samples were analyzed in transmission mode through the microscope after compression in a diamond cell; scans were acquired at a resolution of 4 cm-1. references austin american (1949) ‘new hand-colored photograph print process demonstrated’, 7 june, p. 9. australasia photo-review (1949) ‘flexichrome announced: colour from black-and-white’, 56(7), p. 428. kodak (1949) ‘kodak flexichrome process new color method’, 5(7), pp. 2–3. coe, b. (1978) colour photography: the first hundred years 1840-1940. london: ash & grant. colton, h. c. and thronson, s. m. (1940) ‘dyes for imbibition printing’, photo technique, pp. 54–58. condax, l. m. (1947-1952) monthly reports from the eastman kodak color division from january 1947 to may 1952. rochester: image permanence institute archives. crawford, j. (c.1939) the crawford flexichrome process. new york: the crawford flexichrome company. crawford, j. (1941a) ‘color methods: the flexichrome process’, minicam photography, 5(1), pp. 55, 92–93. crawford, j. (1941b) ‘method of producing multicolored relief pictures’. united states patent 2244905. crawford, j. (1941c) the crawford flexichrome process. new york: the crawford flexichrome company. crawford, j. (1942a) ‘flexichrome process’, the complete photographer, 5(28), pp. 1818–1822. crawford, j. (1942b) ‘flexichrome process for converting black-andwhite photographs into color prints’, the camera: a practical magazine for photographers, 64 (march), pp. 26–27. crawford, j. (1943) ‘color photography’. united states patent 2324069. defender trade bulletin (1940) ‘combined photographic industry and trade show’, 24(1), p. 24. defender trade bulletin (1942). ‘discontinued’, 26(2), p. 19. the flexichrome: visual examination and scientific analysis of an overlooked color process. 15 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140101 deschin, j. (1941) ‘crawford flexichrome process’, scientific american, 164(3), pp. 174–181. dudley, b. (1940) ‘color prints without headaches’, photo technique, 2(6), pp. 35–38. eastman kodak company (1949) color prints with the kodak flexichrome process. rochester, ny: eastman kodak company. eastman kodak company (1950) a kodak color data book: kodak flexichrome process. rochester, ny: eastman kodak company. galmes, m. (1984) masana, fotograf. barcelona: cercle cultural de la caixa de pensions granolles. la jolla museum of art (1969) the photographic art of lynn g. fayman: [exhibition at] la jolla museum of art, january 17-february 23, 1969. la jolla, ca: la jolla museum of art. kodakery: a newspaper for the men and women of eastman kodak company (1949) ‘kodak flexichrome process announced: color prints made from black-white’, 7(23), p. 1. koshofer, g. (1981) farbfotografie band 3: lexikon der verfahren geräte und materialien und materialien das system der verfahren, chronik der farbfotografie. münchen: laterna magica. lipton, n. c. (1949) ‘tools & techniques: a round-up of recent developments and significant trends’, popular photography, 25(3), pp. 22–24. lomax, s. q., schilling, m. r. and learner, t. (2007) ‘the identification of synthetic organic pigments by ftir and dtms’, in modern paints uncovered. los angeles: the getty conservation institute, pp. 105– 117. available at: http://www.getty.edu/publications/virtuallibrary/9780892369065.html maaruf, n. (2021) ‘identifying the rare and elusive flexichrome, insights from the conservation lab’, insights from the conservation lab. available at: https://www.artic.edu/articles/907/identifying-the-rareand-elusive-flexichrome (accessed: 26 april 2021). nadeau, l. (1989) encyclopedia of printing, photographic and photomechanical processes. fredericton, n. b.: atelier luis nadeau. nevada state journal (1941) ‘new film process shown at meeting’, 18 september, p. 5. new york times (1941a) ‘classified ad 2 artist’, 12 december, p. 49. new york times (1941b) ‘classified ad 2 artist’, 4 december, p. 49. new york times (1941c) ‘display ad 40 photographic printer’, 5 december, p. 44. new york times (1941d) ‘notes of camera world color exhibit’, 23 november, p. 7. new york times (1941e) ‘notes of camera world flexichrome demonstration’, 16 november, p. 7. pénichon, s. (2013) twentieth century color photographs: identification and care. los angeles: getty conservation institute. potter, r. s. (1940). ‘the crawford flexichrome process of “colored” photography’. defender trade bulletin, 24(3), pp. 13–14. sipley, l. w. (1951) a half century of color. new york: the macmillan company. stulik, d. c. and kaplan, a. (2013) carbon, the atlas of analytical signatures of photographic processes. los angeles: the getty conservation institute. available at: https://www.getty.edu/conservation/publications_resources/pdf_publicat ions/atlas.html varden, ll. e. (1967) ‘current status of colour photography in the united states’, the photographic journal, 107(4), pp. 104–110. 64 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj.130208b the changes of transparent colours in being laid upon others’: considerations for a new perception of glazes with historical pigments and dyes miquel herrero-cortell 1 , paola artoni 2 , marcello picollo 3 , marta raïch 4 , maria antonia zalbidea 5 1 departamento de comunicación audiovisual, documentación e historia del arte, universitat politècnica de valència (spain), mihercor@har.upv.es 2 laniac, università degli studi di verona, paola.artoni@univr.it 3 ifac-cnr, istituto di fisica applicata “nello carrara” del consiglio nazionale delle ricerche, firenze, 4 caem, universitat de lleida, universitat de lleida (spain) 5 departamento de conservación y restauración de bienes culturales, universitat politècnica de valència (spain), manzalmu@crbc.upv.es corresponding author: miquel herrero-cortell (mihercor@har.upv.es) abstract this article describes a reconstruction of 40 sequences of historical glazes used by most european schools of painters from the 15th to the 18th century. its main objective is to visually document the appearance of colours overlaid with historical pigments and dyes, which have often suffered from a degree of deterioration that renders it difficult to determine their original appearance. we also seek to show the extent to which the historical glazes and overlays can alter our perception of the underlying colour. to this end, lab tests and sources have been used with the aim of suggesting a series of sequences of colour overlays that were widely used in the aforementioned period, so as to reproduce them on a canvas using historical pigments and colours agglutinated in oil, in accordance with the main painting techniques of the era studied. keywords historical pigments; dyes; glazes; colour overlays received 14/08/2021; revised 19/10/2021; accepted 27/10/2021 mailto:mihercor@har.upv.es the changes of transparent colours in being laid upon others’: considerations for a new perception of glazes with historical pigments and dyes 65 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj. 130208b 1. introduction until the 16th century, artists followed the flemish style of producing paintings with a finely glazed appearance, excellent for painting on panels, with several very thin layers of colour interacting with each other, and very rarely using monochrome finishes comprised of a single layer of paint. this approach suggests the need for a different view of the history of oil painting techniques, whose base problem should be considered not in terms of invention or individual discovery (as giorgio vasari has accustomed us to think) but in relation to a long evolutionary process that is documented in the treatise attributed to theophilus presbyter (del vescovo, 2013: 244-255). painting technique remained unchanged even when painters began turning to canvas as a support medium, and it was only between the late 16th and early 17th century that european paintings acquired a more full-bodied appearance. however, glazes continued to be widely used as a technical solution right through to the 19th century, when new trends fuelled the quest for different visual effects, created with thicker brush-strokes. this development was related to the development of industrial colours, much thicker and more opaque, which also dried more quickly and offered a wider palette of colours. glazes began to lose their practical purpose because colour modulation was no longer such a popular technique and although it has continued to be used up to the present day, its application in the 19th century was in fact uncommon. the term ‘glazing’ appeared for the first time in the treatise on the true precepts of the art of painting by giovanni battista armenini (1587), although, as will be discussed below, the concept dates back further. other authors, such as francisco pacheco and antonio palomino, referred to this practice as ‘baños’ (‘bathing’). it is not easy to define exactly what a glaze is: the term designates any translucent or transparent layer of colour placed over a lower layer with the intention of changing the underlying colour, or of giving it a new hue, in order to darken, brighten, or intensify the saturation or to form a compound colour. until the 19th century, the relatively limited nature of the palette necessitated the use of effects of chromatic transparency that could produce more complex tones than those offered by pigments used individually. in reality, rather than glazes, it was common practice to use colour overlays. it is important to remember that the painting technique of overlaying colours was a practice typical of the panel painting of the late gothic period, as documented in chapter lxxxix of cennini’s il libro dell’arte. that same chapter also contains an interesting passage about the process of painting in oil being too slow and dull, a point made previously by theophilus. in chapter xxv of de diversis artibus (hawthorne, j. et al. 1979, [s. xii]) he provides instructions on this painting method ‘[...] whenever you have laid on the pigment, you cannot lay a second over in until the first has dried out. this process is an excessively long and tedious one in the case of figures [...]’) [1], which is expanded on in the following chapters up to chapter xxvii, where he describes the process of ‘translucent’ painting. three centuries later, leonardo da vinci (1817 [s. xvi]) [2], in chapter ccl of his a treatise on painting, would discuss the phenomenon of colour overlay, or ‘[...] the changes of transparent colours in being laid upon others of different kind [...]’, which inspired the title of this article. most of the pigments available on the palette from the 15th to the 18th century were translucent to a certain extent, especially when applied thinly, and more translucent still are dyes, which become lake pigments when they are precipitated on an inorganic substrate such as rock alum, calcium carbonate or sodium carbonate. the use of lake pigments applied over pigments was much more common than is generally believed; moreover, it was essential to the development of a whole range of tones that made it possible to blur the colour and expand the chromatic possibilities (thompson, 1956; bruquetas, 2003; herrero-cortell, 2019). 2. materials and methods the main purpose of this article is to reconstruct some of the main sequences of glazes made from pigments and lake pigments, as practised by europe’s main schools of painting from the 15th to the 18th century, based on paint stratigraphies (which are not included here due to space limitations) and historical sources. due to the relatively rapid degradation of many of these materials, the appearance of the colour can change dramatically over time: the yellowing of oils and darkening of varnishes that tend to occur with these mixtures, as well as other factors like the degradation of dyes and pigments, low stability to light and other environmental parameters, mean that the colours rarely look as they originally did (zalbidea, 2014: 33-37). for example, there are well-known cases of colour instability that have been found in works by painters like lorenzo monaco (ca. 1407), such as the coronation of the virgin, preserved at the national gallery in london, the coronation of the virgin at the uffizi gallery of florence, and the coronation at the courtauld in london (burnstock, 1988). this article has three specific objectives: 1. to reconstruct a palette of colours with glazes that cannot be observed today due to the effect of the the changes of transparent colours in being laid upon others’: considerations for a new perception of glazes with historical pigments and dyes 66 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj. 130208b degradation factors mentioned above. this reconstruction has involved the use of historical pigments and dyes that are largely obsolete today. 2. to highlight how glazes or overlays of these translucent materials are able to alter the viewer’s perception of the underlying colours. 3. to provide a set of standards for future spectroscopic and multi-band imaging studies in the form of the test strips processed for this study. the performance of this study required the application of 40 sequences documented in written sources and stratigraphies. most of the pigments used to produce the test strips were provided by the company kremer, although some pigments, such as saffron, reseda and kermes, have been developed using traditional recipes, fixing the dye with rock alum in cases that so required. the pigments used were: smalt (10000); azurite (10204); natural ultramarine, from lapis lazuli (10510); indigo (36007); vermilion (42000); minium (42500); english red deep (40545); laccifer lacca carmine (lac dye) (36020); rose madder; cochineal; italian gold ochre (40220); orpiment (10800); naples yellow, based on lead antimony (10130); reseda lake, prepared by hand according to traditional recipes; saffron lake; green earth (40810); natural malachite (10300); verdigris (44450); and sap green (37391). although it is a short list, the choice of products was based on their importance and distribution, which is why some materials used only in very specific locations and periods, such as orchilla, have been omitted. 1st layer eg: green earth 2nd layer eg: verdigris the colour results fig. 1. the colours were arranged according to the diagram. the colour results interacting with the colour from the two layers. eg: a second layer of verdigris was applied over a first layer of green earth. various overlays of glazed colours were applied, ordered by hue: blue, yellow, red, green, a second green obtained by mixing yellow and blue, purple colours obtained by mixing red and blue pigments. both the pigments and the lakes were agglutinated in linseed oil, ground with a porphyry stone and applied to the test strip so that the base colour, the colour of the glaze and the colour resulting from the overlay could all be viewed individually and simultaneously (fig. 1). the support medium was a linen cloth prepared first with natural glue (as a “primer coating”), followed by four additional layers of primer comprised of glue and calcium sulphate hemihydrate. the test strips were photographed with a nikon d800 camera and colour card, with colour and white balance correction using an aic card. 3. results and discussion 3.1. blue the traditional blue pigments are not very opaque and were often used for glazes. in tempera painting it was common to apply them with glue over a layer of red earth, as documented and confirmed by stratigraphic studies of mural painting up to the 15th century in both italy and spain. painters often worked to create glazes with these blues, a practice that pacheco adamantly condemned, except when the overlays were made with ultramarine: ‘i do not endorse bathed blues, unless made with ultramarine’ [3] (pacheco, 1649: 392). years later, antonio palomino would specify that ultramarine blue: ‘is used in two ways; either bathed or fashioned out of any of the other blues already made’ [4] (palomino, 1947 [1715]: 501). smalt is a colour preferably used al fresco, but due to the sensitivity of its tone and its characteristic transparency as a result of its vitreous nature it was greatly valued for making glazes in oil as it has a more vivid tone than azurite. tempering was also done with oil and varnish (price, 2017: 135-154), although their blackening or yellowing tendencies were well known, due to effects derived from crushing the particles and because their index of refraction is very similar to that of oil used as a binding agent (döerner, 1998: 69). the use of smalt blue over azurite (fig. 2. sample 1) was common in the 16th and 17th centuries, although its introduction to the colour palette is identified by bensi (1980: 33-47) as being around 1470-80. its presence in layers has been documented in the veneto region, and also among some spanish baroque painters. the choice of two inorganic blues on a palette is certainly not commonplace, but as smalt is more vivid than azurite and even more transparent, it was sometimes used to give the blue a more saturated tone. for example, in his treatise pacheco (1649) attests to the use of these two pigments together, although not as glazes. it was much more common for azurite to be covered by ultramarine lapis lazuli (fig. 2, sample 2). in fact, as it was slightly opaque and particularly expensive, ultramarine was reserved for the final layer of glaze. this is how the portuguese painter felipe nuñez explains it in his treatise of 1615. the changes of transparent colours in being laid upon others’: considerations for a new perception of glazes with historical pigments and dyes 67 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj. 130208b it was clearly a widespread practice to apply lapis lazuli over azurite or another blue, as can be found in numerous stratigraphies showing one or more azurite or even smalt layers under the ultramarine layer, and it is also recommended in théodore turquet de mayerne’s treatise in 1620 (fels, d. 2010: 141). prussian blue on top of azurite (fig. 2, sample 3) was similarly used, but this blend was much less common and was largely limited to the 18th century. prussian blue is dark by nature and it was therefore used to give greater depth to the azurite, especially when the latter was less pure or more greyish, or for the purpose of shading. indigo is a dye that was used widely in painting from the 14th through to the 19th century, although it has not received the attention it deserves. it was an economical solution when more expensive blue pigments could not be obtained (herrero-cortell, 2019: 13-15). indigo of european origin was known as woad (even it was not pure woad, but a mixture [guado puro o misto a travertino], according to brunello, 1975: 194) and the asian dye was known as woad indigo. in both cases, its main dye is the same and its colour was identified with the term ‘indigo’. its use added to other blue pigments to enhance them was documented by eraclius in de coloribus et artibus romanorum: [...] shade azure with indigo, lay on the lights with white lead [...] (merryfield, 1967: 257) [5]. both lapis lazuli over indigo (fig. 2, sample 4) and indigo over lapis lazuli (fig. 2, sample 7) are used in shaded areas, for example in the folds of clothes. lapis lazuli with black changes to dark grey, and the only way to give it depth and sheen without making it opaque is to add woad or indigo. this combination, which was already commonplace in medieval painting, continued to be used until the 16th century. in his treatise, palomino explains how the blue movement needed to be darkened with woad (indigo): ‘[...] having to be fashioned, its tints of clear, and dark, can be blended in, mixing in proportion with the lead white in walnut oil, and enhancing the strong darks with the indigo.’ [6] (palomino, 1947 [1715]: 501). even pacheco mentions this custom, although with reference to azurite (fig. 2, sample 5). like indigo used with smalt to add shade to the vibrant tone of this blue (fig. 2, sample 6), a very common solution in the 16th century in the painting schools of spain and northern italy, such as the venetian school, was to use both smalt and indigo to create these finishes. indeed, the padua manuscript (written in venice around 1580) reads: ‘[...] blue azure with indigo, lay on the lights with white lead [...]’ [7] (merryfield, 1967: 657). fig. 2. blue samples. 1) smalt over azurite; 2) lapis lazuli over azurite; 3; prussian blue over azurite; 4) lapis lazuli over indigo; 5) indigo over azurite; 6) indigo over smalt; 7) indigo over lapis lazuli 3.2. yellow the use of lake pigments and inks for yellow glazes was a very common practice in painting and is mentioned constantly in the treatises. in very rare cases stratigraphy reveals that yellows were made with pigments, given their high covering power. yellow lakes (saffron, reseda and sap green) suffer considerably from deterioration and are highly unstable to light, making them difficult to recognise. for this study we chose to use lead antimony (commonly known as naples yellow), which was often included on the palettes of 16th-century painters, lacking the option to use lead-tin yellow (giollorino or giallolino zaldolino, as it was known in italy, while in france it was known as massicot; it is often confused with naples yellow or antimony yellow), which was used as a base colour until the 17th century. saffron is one of the dyes most frequently found in recipes, associated with the colour change in the crushing and mixing stage, although it could be applied in glaze form to deepen or saturate the tone of other yellows on a lower layer (fig. 3, samples 8, 10, 12), like reseda (fig. 3, samples 9, 11, 13). both saffron and ochre are mentioned in the late-14th century by cennini, who, with respect to saffron, observed: do not expose it to the open air, for it soon loses its color […] (ch. xlix) [8]; however, it is a direct dye (that does not need a mordant) that was used frequently, as palomino attested. with respect to reseda (known in spanish as ancorca), palomino observes: ‘greenish-yellows are made by beginning the clear with lead-tin yellow, and adding ancorca to the second dye [...] and after it is dry, it is bathed in ancorca, and dried, and touching the clears with giollorino, where suitable, and squeezing the darks with the shade, leaving an excellent yellow.’ [9] (palomino, 1947 [1715]: 50). this practice varied from region to region; for example, in northern europe it was more common to use stil de grain yellow, which was sometimes referred to with the name dutch pink. in 1620, théodore turquet de mayerne wrote of ‘[...] massicot shaded off with dutch pink [...]’ (fels. 2010: 141). the changes of transparent colours in being laid upon others’: considerations for a new perception of glazes with historical pigments and dyes 68 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj. 130208b finally, we considered the overlaying of naples yellow ochre and orpiment (fig. 3, samples 14-15), two pigments that are relatively opaque but that appear in stratigraphies in a preliminary application of ochre. fig. 3. yellow samples. 8) saffron obver naples yellow; 9) reseda over naples yellow; 10) saffron over orpiment; 11) reseda over orpiment; 12) saffron over ochre; 13) reseda over ochre; 14) naples yellow over ochre; 15 orpiment over ochre. 3.3. red cinnabar/vermilion (mercury sulphide pigment) and minium (red lead), together with red earths, are historically the red pigments par excellence. none is known for being very translucent, although red lead and mercury sulphide pigments can produce this effect when used in thin layers; in fact, they have been used in this way over layers of very dark red earths, even in mural painting (calabria et. al, 2019) (fig. 4, samples 16-18). most of these overlays have lead, applied both on top of red earth (fig. 4, sample 17) and on top of cinnabar (fig. 4, sample 18), creating a similar visual result. cennini, for example, suggests that: ‘lf you would make a silk drapery either on panels or on walls, lay on the ground with cinnabar and lighten with minium, or if you like with sinopia, and lighten with giallorino on walls’ [10] (cennini, 1971 [s. xiv]: ch.cxliv). however, this overlay was less common than those done with red lake, the queen of the glazes in the red range. red lake pigments were usually made with madder but dye lakes, kerria lacca or indian lake (lac dye) and, to a lesser extent, kermes, known as the european cochineal, were also used (herrero-cortell, 2019). the application of lake pigments as glazes over layers of inorganic reds was widespread, although occasionally they formed localised glazes. in his treatise, da vinci specifies the following procedure: ‘[…] to make a fine green take green and mix it with bitumen and you will make the shadows darker. then, for lighter [shades] green with yellow ochre, and for still lighter green with yellow, and for the high lights pure yellow; then mix green and turmeric together and glaze every thing with it […].’ [11] (da vinci, the notebooks: ch. ix). the hues of the lake pigments are varied and may cover a wide spectrum of reds depending on the method they were processed with and also on the colourant used. madder lake covers the widest spectrum of reds, ranging from a pink-orange to a violet red, and including carmine, deep red and maroon. the lake sequence over cinnabar/vermilion was used constantly from the 14th through to the 19th century; it is among the most cited in the literature and probably one of the most frequently found in stratigraphies (fig. 4, sample 19-21). all over europe in the 14th and 15th centuries it was common to add a little of saffron when tempering minium or vermilion to give them a warmer hue, since they sometimes could look quite cold (thompson, 1956: 108). a madder lake glaze applied over minium was also very common, resulting in a deep red-orange colour (fig. 4, samples 2223). under the lake glaze there is often a mixture of several reds (such as vermilion, minium and lake) and white lead, as the underlying combinations of lakes are often the pink tones resulting from the same lake mixed with white lead (fig. 4, samples 24-25). thus, for example, in his treatise théodore turquet de mayerne suggests: ‘[…] [take] lake and white, and if you want, glaze with lake. the work will be very beautiful. [or] lake, vermilion and white. you can glaze it with lake […]’ (fels, 2010: 14). fig. 4. red samples. 16) vermilion over red earth; 17) red lead over red earth; 18) red lead over vermilion; 19; madder lake over vermilion; 20) lac dye over vermilion; 21) cocchineal lake over vermilion; 22) madder lake over red lead; 23) lac dye over red lead; 24) lac dye over a misture of lac dye with white lead; 25) madder lake over a mixture of madder lake and lead white. 3.4. green due to their transparent nature, greens were used a great deal as glazes, in one or more layers over a grisaille in black and white, as recommended, for example, by pacheco, who maintains that: ‘[…] some [greens] are fashioned with black and white in oil and then bathed in ground verdigris with linseed oil’ (pacheco, 1990 [1649]: 484) [12]. the use of verdigris with varnish (which itself produces an amber colour), or of copper resinate, is well documented throughout the literature, including the the changes of transparent colours in being laid upon others’: considerations for a new perception of glazes with historical pigments and dyes 69 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj. 130208b writings of armenini (1587: 126) and de mayerne (fels, 2010: 139, 142), according to the precept appearing in the brussels manuscript: ‘[…] to make very beautiful green for glazing, verdigris must be used with varnish’ [13] (merrifield, 1967: 812). but verdigris was not the only pigment that could be used for this purpose: many green earths, for example, are highly transparent when tempered with oil, but their tone is not generally either saturated or vivid (döerner, 1998: 75). sometimes they were used as glazes over other colours, such as ochre or sienna, indigo or a grisaille modulated over black, as recommended by palomino (1988: 505), and they often served as a base for a glaze with a different green or yellow. when malachite is overlaid, the tone is also more consistent, and tends to have more body (fig. 5, sample 26). these stratified layers were commonplace and are documented in painting: a cheaper pigment, like earth, was applied under a more expensive one, like malachite, which is quite transparent. it was more common to use verdigris or copper resin for glazes over green earth and then to apply malachite over that, thereby producing darker and deeper tones (fig. 5, samples 27, 30). in some cases an organic green could be used, such as sap green, which is translucent like other lakes, although it has a brownish and less vivid tone, which is why most writers did not consider it to be among the ‘noble’ colours. fig. 5. green samples. 26) malachite over green earth; 27) verdigris on green earth; 28) sap green ver green earth; 29) sap green over malachite; 30) verdigris over malachite; 31) sap green over verdigris; 32) reseda lake over azurite; 33) reseda lake over green earth; 34) reseda lake over verdigris; 35) reseda lake over malachite. in other cases, green was produced by overlaying a yellow (always in the form of a lake) on a preceding green or blue like azurite (fig. 5, sample 32), as recommended by eraclius: ‘[…] if you wish to make a colour like lily green, mix azure with white lead; shade it with azure; lay on the lights with white lead; and when it is dry, cover it over with clear saffron […]’ [14]. (merrifield, 1967: 257). indeed, the addition of yellow dyes to verdigris to make a colour that was less cold is a constant in the literature. there are numerous recipes for verdigris, including, for example, the addition of reseda or saffron while crushing and preparing the mixture, or even making a verdigris blend with certain dyes to apply the final glaze, as recommended by da vinci: ‘[...] then mix green and turmeric together and glaze every thing with it [...]. (da vinci, the notebooks: ch. ix) [15]. he recommends the same with saffron, unless it becomes discoloured quickly, and with yellow from aloe: ‘[...] supposing the verdigris has already been used, and the part finished, you may then glaze it thinly with this dissolved aloe, and it will produce a very fine colour [...].’ [16] (da vinci, 1817, [16th century], ch. ccxxix). the greying tendency of verdigris can be definitively corrected by adding a yellow lake pigment, which results in a deeper and more saturated colour (fig. 5, sample 34), although it is common for yellow lakes to appear over other greens (fig. 5, samples 33-35). 3.5. purple traditionally associated with dyes, purple is a compound colour, although some purples can be made using a violet lake pigment, such as orchilla or cochineal, over a grisaille base (fig. 6, sample 37). orchilla is a material rarely mentioned in the treatises, although palomino (1947 [1715]: 1164) decided to include it in the list that appears at the end of his treatise containing the most commonly found colours on the painter’s palette. most of the purples used were mixtures of a pigment and a blue or red dye, or overlays of glazes created with a transparent blue or red, as recommended by théodore turquet de mayerne: ‘purple is made with smalt and lake […]’ (fels. 2010, 141). indeed, the best violet tones are obtained by mixing or overlaying red lake over smalt or lapis lazuli (fig. 6, samples 38-40), according to a practice previously described by cennini (1971 [s. xiv]: ch. lxxiii). fig. 6. purple samples. 36) cocchineal lake over indigo; 37) cochineal lkake over a misxture of such lake with white lead; 38) cochineal lake over smalt; 39) cochineal lake over azurite; 40) cochineal lake over lapis lazuli 4. conclusions what colours would we see if we entered the studio of an artist from the past who had just finished a painting? what did the colours look like before the oil or varnishes the changes of transparent colours in being laid upon others’: considerations for a new perception of glazes with historical pigments and dyes 70 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj. 130208b altered the appearance of the paint with their natural oxidation? and how would they look if they had never undergone the (sometimes aggressive) cleaning processes they were subjected to? this article has presented a reflection on the artistic literature, in the form of treatises, which provide very few guidelines for the reproduction of the recipes, but which document workshop practices that have provided the information needed to reconstruct 40 colour overlays made with pigments and dyes, agglutinated with linseed oil used as a medium for the glazes. the picture this provides is immediate: it not only offers a kind of baseline, but also facilitates a much-needed reflection on which glazes can actually change the colour tones and our perception of those colours. 5. conflict of interest declaration the authors wish to state that no financial or personal interests have affected the objectivity of the study, and that no conflicts of interest exist. 6. funding source declaration authors wish to state that no external funding has been involved for this study. 7. acknowledgment the authors wish to thank anna victòria pedret and andrea la bella, for their help in the developing of the study. they also wish to thank departamento de comunicación audiovisual, documentación e historia del arte from the polytechnic university of valencia (upv), for supporting the translation costs. 8. short biography of the author(s) miquel herrero-cortell he holds a phd in art history. he has a degree in fine arts from the polytechnic university of valencia (upv) and a degree in art history from the university of valencia (uv). he holds a master’s degree in conservation and restoration of cultural heritage and a master’s degree in artistic production. he has developed his work as a researcher focusing on the field of materials and painting techniques, as well as on painting diagnosis. he is currently teaching at the universitat politécnica de valència. paola artoni she holds a phd in beni culturali. from 1999 to 2009 she worked for ministero per i beni e le attività culturali in the museum of the ducal palace in mantua. since 2010 she’s functionary technical responsible of the centre laniac (laboratorio di analisi non invasive per l’arte antica, moderna e contemporanea), in dipartimento di culture e civiltà, (university of verona). she held courses for introducing non-invasive diagnostics applied to cultural heritage in the same university, from 2011 up to now. marcello picollo – he has a phd in photonics from the university of eastern finland and a graduate degree in geology from the university of florence. he is a researcher at the institute of applied physics “nello carrara” of the national research council of italy (ifaccnr), florence. he has been working on spectroscopic investigations of works of art since 1991; his main research focus is on artists’ material characterization using non-invasive spectroscopic and imaging techniques. since 2009, he has been the coordinator of the ifac applied spectroscopy group on the research line “integrated spectroscopic instrumentations and methodologies for the diagnosis and monitoring of cultural heritage objects and environment. marta raïch she has a degree in audiovisual communication by the university of lleida (spain). she is a technician in image production. she is specialized in scientific photography applied to works of art, as well as artistic diagnosis. she is currently developing her research and work as a technician at the centre d’art d’època moderna (caem) of the udl where she carries out technical and scientific imaging, while she also develops design and layout tasks. maria antonia zalbidea professor in the department of conservation and restoration of cultural heritage at the upv, field in which she holds a doctorate degree. she has directed her research on the procedural, material and conservative aspects of mural painting, as well as parts related to varnishes and dyes in painting. at present she is also a collaborator in the master’s degree in analysis and authentication of works of art at the uv. notes [1] ‘[…] ac deinceps accipe colores quos impugner volueris, terens eos diligenter oleo sine aqua, et fac mixturas vultuum ac vestimentorum sicut superius aqua feceras […].’ [2] quando un colore trasparente è sopra un altro colore variato da quello, si compone un color misto diverso da ciascuno de’ semplici che lo compongono. […] e cosí il paonazzo dato sopra l’azzurro si fa di color di viola; e quando l’azzurro sarà dato sopra il giallo, egli si farà verde; ed il croco sopra il bianco fa giallo; ed il chiaro sopra l’oscurità fa azzurro, tanto piú bello, quanto il chiaro e l’oscuro saranno piú eccellenti. [3] pacheco states: ‘los azules bañados no los apruebo, si no es con ultramarino’. [4] palomino states: ‘se usa de él en dos maneras; o bañado, o labrado sobre cualquiera de los otros azules ya concluidos’. the changes of transparent colours in being laid upon others’: considerations for a new perception of glazes with historical pigments and dyes 71 color culture and science journal vol. 13 (2) doi: 10.23738/ccsj. 130208b [5] the original text saids: ‘[...] indicum incides de lazurio, matizabis de albo plumbo [...]’. [6] palomino states: ‘[…] habiendo de ser labrado, se pueden ir metiendo sus tintas de claro, y obscuro, mezclándole, en proporción, con el albayalde de nueces, y ayudando los obscuros fuertes con el añil. [7] the original text saids: ‘azurro (...), smaltino, e biadetto, s’ombrano con indico, laca e negro.’ [8] cennini states: ‘[...] guardati non vegga l'aria, chè perde subito suo colore [...]’. [9] ‘los escarolados se hacen comenzando el claro con el génuli, y añadiéndole ancorca a la segunda tinta [...] y después de seco, le dan un baño de ancorca, y secante, y tocarle los claros con genulí, donde es conveniente, y apretarle los obscuros con la sombra, y queda un amarillo excelente’ [10] cennini states: ‘se vuoi fare drappo di seta, o in tavola o in muro, campeggia di cinabro, e pallia o ver vitica di minio; o vuoi di sinopia, e pallia di cinabro [...]’. [11] leonardo da vinci states: ‘per fare un rosso bello: togli cinabrese e mista con anguria arsa pell’ombre iscure, e pelle più chiara, matita e minio, poi vela con lacca bella […].’ [12] pacheco states: ‘[…] se labran algunos con blanco y negro a olio y después lo bañan con cardenillo molido con aceite de linaza’. [13] ‘pour faire de très beau verd galssé, faut employer le verdigris avec du verny […].’ [14] the original text saids: ‘si vis facere clorem similem gladio viridi, misce lazurium cum albo plulmbo, et quando fuerit siccus, coperi de claro croco […].’ [15] leonardo states: ‘[…] di poi togli verde e curcuma insieme e vela sopr’ogni cosa’. [16] leonardo states: ‘[…] e se tu avessi finito un’opera con esso verde semplice, e poi sottilmente la velassi con esso aloe (risuluto in aqua), allora essa opera si farebbe di bellissimo colore […]’. references armenini g.b. (1587). de’veri precetti della pittura. ravenna. bensi, p. (1980). ‘gli arnesi dell'arte. i gesuati di s. giusto alle mura e la pittura del rinascimento a firenze’, studi di storia delle arti, n 3, pp. 33-47. brunello, f. (1975). de arte luminandi e altri trattati sulla técnica della miniatura medievale, neri pozza, vicenza. bruquetas, r. (2002). materiales y técnicas de la pintura española de los siglos de oro, madrid: fundación de apoyo a la historia del arte hispánico. burnstock, a. (1988). the fading of the virgin's robe in lorenzo monaco's' coronation of the virgin', national gallery technical bulletin, 12, pp. 58-65. calabria salvador, i. & zalbidea muñoz, a. (2019). estudio de las pinturas murales de la sala del mosaico de los amores de la ciudad íbero-romana de cástulo, ge-conservación/conservação (16), 45-61. doi: https://doi.org/10.37558/gec.v16i0.663 cennini, c. (1971) il libro dell’arte, a cura di f. brunello, vicenza: neri pozza. da vinci, l. (1817) [s. xvi]. trattato della pittura, rome. da vinci, l. (1970) [s. xvi]. the notebooks of leonardo da vinci, compiled and edited from the original manuscripts by jean paul richter. london: dover. da vinci, l. [s. xvi]. the notebooks of leonardo da vinci, available at: https://en.wikisource.org/wiki/the_notebooks_of_leonardo_da_vinci/i x (accessed: 8 july 2020). del vescovo, p. (2013). il trattato di teofilo come testimonianza della storia dell’origine della pittura ad olio: un esempio di metodo interdisciplinare nello studio di una tecnica pittorica. in: zwischen kunsthandwerk und kunst: die‚ schedula diversarum artium. de gruyter, pp. 244-255. doerner, m. (1998). los materiales de la pintura y su empleo en el arte, 3rd ed. barcelona: reverté. fels, d. (ed.) (2010). lost secrets of flemish paintings, 3rd ed. eijsden: alchemist publications. herrero-cortell, m. (2019). ‘los colores de un imperio’ hispanic production and international trade of pigments and pictorial materials in the sixteenth century’, journal for art market studies, 3(2), pp.1-16. hawthorne, j. et al. (1979). theophilus on divers arts: the foremost medieval treatise on painting, glassmaking and metal-work, translated from the latin with introduction and notes: new york: dover. merrifield, m. (1967). medieval and renaissance treatises on the arts of painting, 2nd ed. london: dover. pacheco, f. (1990) [1649]. arte de la pintura, madrid: cátedra. palomino, a. (1947) [1715]. museo pictórico y escala óptica, madrid: aguilar. price, m. (2017). renaissance mysteries. volume i: natural colors. london: page publishing. thompson, d. (1956). the materials and techniques of medieval painting, london: dover. zalbidea muñoz, m. a. (2014). els vernissos artístics. revisió i evolució, valencia: editorial universitat politècnica de valència, pp. 33-37. https://doi.org/10.37558/gec.v16i0.663 https://en.wikisource.org/wiki/the_notebooks_of_leonardo_da_vinci/ix https://en.wikisource.org/wiki/the_notebooks_of_leonardo_da_vinci/ix 41 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110105 evolution of colours in football shirts through colorimetric measurements: fiorentina's case. alessandro farini 1 , elisabetta baldanzi 1 , marco raffaelli 1 , francesco russo 2 1 cnr-istituto nazionale di ottica. alessandro.farini@ino.it, elisabetta.baldanzi@ino.it, marco.raffaelli@ino.it 2 franci.russo91@gmail.com corresponding author: alessandro farini 1 (alessandro.farini@ino.it) abstract football fans express their identification with their team especially with colours of football shirts. the respect of “tradition” is something so important that very small changes can provoke anger in fans, who express their opposition in news and social media. this could create problems for merchandising. fiorentina (florence’s football team) wears purple shirts, very uncommon in football world. in collaboration with fiorentina museum we have measured, with two different spectrophotometers, colours of shirts from the fifties to nowadays. we have evaluated the problems related to ageing and we have measured different points from the same shirts, different shirts from the same season and details different from the purple colour (e.g white used for numbers). measurement show a clear change in colour during the considered years, strictly related with the introduction of colour television and new strategy of merchandising. furthermore it is evident that every kit manufacturer prefer creating its own colour despite the existence of an “official” fiorentina’s colour. such measurements, made on shirts of proved authenticity, permit to improve the analysis about “historical shirts”, helping to discriminate between authentic or fake shirts: an important topic because an original shirt from fiorentina first italian league winner season could be sold for 5000 €. one example of very well done fake shirts is illustrated. keywords colorimetry, purple, colour in textiles, colour in sports, aging of textiles received 05 june 2017; revised 11 september 2018; accepted 23 may 2019 citation: farini, a., baldanzi, e., raffaelli, m., & russo, f. (2019). evolution of colours in football shirts through colorimetric measurements: fiorentina’s case. color culture and science journal, 11(1), 41–46. https://doi.org/10.23738/ccsj.110105 mailto:alessandro.farini@ino.it mailto:franci.russo91@gmail.com mailto:alessandro.farini@ino.it evolution of colours in football shirts through colorimetric measurements: fiorentina's case. 42 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110105 1. introduction colours of shirt for football teams are a very important part in the process of identification from fans. a football club can change every player, president, trainer and this is completely acceptable for every fan, while a change in colour could be considered as a betrayal of its history. this could create problems for merchandising (derbaix and decrop, 2011). fiorentina (florence’s football team) is one of the few teams in the world wearing purple shirts (salvi and savorelli, 2009). probably for this reason shirt’s colour is a very sensitive topic for fiorentina’s fans. in the recent years the introduction of high definition colour television and new strategy of merchandising have assigned an important role to shirt’s colour. checking and reproduction of official colours of a football team is nowadays very important. 2. material and methods thanks to the help of museo fiorentina (www.museofiorentina.it) we have received at our lab 50 original shirts belonging to different sport seasons. every shirt is called using the year of the second part of the season; as an example, the shirt used during the season 1958-1959 will bel called 1959. we have measured every shirt using a minolta spectrophotometer cm-2500c with 10 nm of resolution, 45°/0° geometry optics and 360-740 nm wavelength range. we have checked our measurements using, on three samples, a very accurate instrument: a perkin elmer spectrophotometer lambda 900 with an integrating sphere. the measurements of the two instruments agree within the experimental error (cm2500c has a repeatability of e * ab=0.04 and an interinstrument agreement e * ab=0.06): we decided to use cm-2500c that permits to see the exact point of measurement. this peculiarity is very useful, because it permits to measure also shirts where some colour are present in a very small area. in order to apply some colorimetric formulas we have used some algorithms from (westland et al) and some others written by ourselves. fig. 1 – reflectance spectra for 1959-1967-1968-19691970. fig. 2 – fiorentina’s shirt for season 1958-1959. evolution of colours in football shirts through colorimetric measurements: fiorentina's case. 43 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110105 ageing is a real problem in this kind of measurements. nowadays every shirt is used only one time but during the 70’s and before every shirt could be used and washed many times during a season, producing a degradation in colours. furthermore, old shirts could be inhomogeneous in colours: in order to check this hypothesis, we have measured the same shirt (1959, the oldest available where the ageing problem should be greater) in ten different points apparently of the “same purple”. the results expressed in the cielab system with 2° observer and d65 illuminant are are l * =25.1±0.7, a * =27.9±0.7, b * =-42.4±0.9. 3. experimental results for every shirt we can examine the reflectance spectrum and the colour coordinates. here we present only some data in order to present the variability trough years: a complete report will be published in the future together with some psychophysical measurements that want to investigate if every fiorentina shirt could be called “purple” nowadays. in fig.1 the reflectance spectra of 1959 (the oldest shirt available at museo fiorentina when we made the measurements) 1967, 1968, 1969, 1970 are shown. the first 4 shirts are very dark (shirt of 1959 is presented in fig.2). this is a typical feature of the shirts in the “golden age” of fiorentina (fiorentina won the championship in 1955-1956 and 1968-1969): a radio show devoted to fiorentina is called “viola scuro” (dark purple in italian) in order to create a link with these famous years. the 1970 shirt is redder and less dark. 1982 (fig.3) is a very famous shirt for the history of fiorentina because in that year many football team decided to renovate their shirt and their logo. probably we can define 1982 as the first year of the “modern football”. the year before fiorentina’s logo was completely renewed with an overlap between the traditional red fleur-de-lis and a capital "f", for fiorentina. supporters disliked it when it was introduced, but the logo remained until 1990. in the same year for the first time in italy a sponsor name was allowed on the shirt. 1982 is the brightest shirt in fiorentina history. its difference is evident looking at lightness, but also looking at reflectance spectra (fig.4). fig. 3 fiorentina’s shirt for season 1981-1982. evolution of colours in football shirts through colorimetric measurements: fiorentina's case. 44 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110105 fig. 4 – reflectance spectra for 1959-1982-1983. 1982 is brighter compared with 1959 (that we can consider the golden standard) but also with 1983. another important year was 1978 because for the first time on fiorentina’s shirt appeared the logo of the “technical sponsor”: adidas. the “technical sponsor” is the factory producing shirt, socks, shorts and other part of the kit and should not be confused with the main sponsor previously cited that could be completely unrelated with football’s world. in 1979 adidas produce the first synthetic shirt (until that year the shirts were made using wool). despite these great changes reflectance spectra are quite similar (fig.5) because probably adidas made a big effort to maintain the same colour. fig.5– reflectance spectra for 1977-1978-1979. transforming the cielab coordinates into cielch coordinates (wyszecki and stiles) it is possible to study the evolution of the hue. we have calculated h * ab (variation in the hue) using as reference point 1959 shirt. using this approach, it is very evident the change in hue happened in 1970 (fig.6). fig.6– h from 1959 evaluated for 1967, 1968, 1969. in 1970 there is a big change in hue. but particularly interesting is the relationship between technical sponsor and hue. every technical sponsor tends to use a “proprietary” purple, realising its own colour. looking at fig.7 we can note that there is a good correspondence between technical sponsor and hue. fig.7– h from 1959 evaluated for seasons from 19921993 to 2000-2001. at the same colour correspond the same technical sponsor this behaviour is also evident looking at season from 2002-2003 to 2012-2013 (fig.8). evolution of colours in football shirts through colorimetric measurements: fiorentina's case. 45 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110105 fig.8– h from 1959 evaluated for seasons from 20022003 to 2012-2013. at the same colour correspond the same technical sponsor 3.1. comparison between authentic and fake shirts colorimetric analysis could be very useful also to distinguish authentic historical shirt from fake shirt. an authentic fiorentina’s shirt for example from 90’s can be evaluated 300 €, but a shirt from 60’s can be sold at 5000 € and this evaluation provokes a big market for fake reproduction. recently we have examined a shirt pretending to be an original shirt from season 1969-1970. comparing this shirt with two original shirts from museo fiorentina (museo fiorentina receives some shirts directly from players admitted to the hall of fame) we have noticed that the red of the fleur-de-lis in the tested shirt is completely different (eab=9.3) from the red of the two original shirts. instead the red of the two original shirts is the same (eab=0.7). obviously this is not a decisive proof, because in those years, before the introduction of official technical sponsor, some differences could be due to different suppliers. but it is a hint that, together with the analysis of textiles and weave, can help an expert in his/her evaluation. 4. conclusions through the years purple in fiorentina’s shirts is changed in many different ways. while the first shirts are dark, nowadays we can see very bright shirts that result pleasant on the tv screen. a definitive fiorentina’s purple do not exist: every technical sponsor creates its own purple. a colorimetric analysis could be useful in order to discriminate between authentic and fake shirts. we have inserted in this paper data regarding some interesting periods for fiorentina’s shirts. people interested to the whole archive of data can contact the authors. 5. conflict of interest declaration the authors state that no actual or potential conflicts of interest exist including financial, personal or other relationships with other people or organizations within three years of beginning the submitted work that could inappropriately influence, or be perceived to influence, their work. 6. funding source declaration this research did not receive any specific grant from funding agencies in the public, commercial, or not-forprofit sector. 7. acknowledgment the authors want to thank museo fiorentina for having made available the shirts and especially its president david bini for his willingness. he also helped us with many historical data about fiorentina’s shirts. 8. short biography of the author(s) alessandro farini is a physicist with phd in optics. he is the head researcher of the visionlab at the cnrnational institute of optics in florence, lab devoted to applied psychophysics. farini’s research work is addressed to lighting, ophthalmic optics and colorimetry. he is teaching geometrical optics and physical optics at the university of florence, degree in optics and optometry. farini is involved in science outreach. elisabetta baldanzi degree in physics at pisa university with a thesis entitled "collisional coupling between the stark components in the rotational spectrum of ch3f", scholarship in science communication at the national institute of physics of matter in genoa, targetti foundation lighting academy coordinator. currently at the national institute of optics of the national research council based in florence in the laboratory of ergonomics of view, research on issues related to psychophysics of vision, lighting and ophthalmic optics. marco raffaelli achieved in 2013 his bachelor degree in optics and optometry at the university of florence, with a thesis entitled: “photometric and psychophysical characterization of some mobile phone displays”. since november 2013 he has been working at the cnr-ino of florence as diagnostic technician for the non-invasive study of artworks and as collaborator with the laboratory of psychophysics of vision. francesco russo was born in florence and studied as an electrical expert at the meucci institute in florence. he took a degree certificate in optics and optometry at the university of florence in 2014 and, in the same year, the optical diploma at vinci. he has been employed of evolution of colours in football shirts through colorimetric measurements: fiorentina's case. 46 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110105 gestione silo (florence) since 2015. this paper concerns his degree thesis. references (derbaix and decrop) derbaix, christian, and alain decrop. "colours and scarves: an ethnographic account of football fans and their paraphernalia." leisure studies 30.3 (2011): 271-291 (salvi and savorelli) s. salvi and a.savorelli, “tutti i colori del calcio”, (le lettere, firenze, 2009). (wyszecki and stiles) wyszecki g. and stiles w.s. (color science concepts and methods, quantitative data and formulae (2nd ed.). wiley-interscience, london, 2000 (westland et al.) westland s., ripamonti c. and cheung v. computational colour science using matlab. wiley, london, 2012 microsoft word 150103 19 color culture and science journal vol. 15 (1) doi: 10.23738/ccsj.150103 a comparative study of lipstick shades preferences by geographical areas hélène de clermont-gallerande1, emmanuelle mauger1, nicolas rolland1 1 chanel parfum beauté, innovation, research & development, 8 rue du cheval blanc, pantin, france. helene.declermontgallerande@chanel.com, emmanuelle.mauger@chanel.com, nicolas.rolland@chanel.com corresponding author: hélène de clermont-gallerande (helene.declermontgallerande@chanel.com) abstract international cosmetics companies manufacture make-up products that are then sold in all countries where the brand is distributed. lipstick ranges today each include about 30 shades and each brand offers several ranges with different effects of the make-up result. a couple of years ago, chanel lipsticks provide 142 shades divided into several ranges: 34 classic lipsticks, 48 shiny lipsticks, 39 intense lipsticks and 21 matt lipsticks. it seemed to us worth looking too, at the 20 best-selling lipsticks by specific geographical area. so, the areas studied are not of comparable size because they are those where detailed sales figures are available. these areas are france, italy, the uk, the usa, asia and south america. the best sales per area are statistically analyzed to establish shade preferences in each of these areas. a principal components analysis then made it possible to establish the geographical areas whose lipstick color choices are closest. a red satured, middle ligthness was unanimously preferred internationally. italy and france were the two markets most representative in terms of lipstick shades. keywords shades, preference, lipsticks, color, geographical area received 12/11/21; revised 25/10/22; accepted 02/11/22 a comparative study of lipstick shades preferences by geographical areas 20 color culture and science journal vol. 15 (1) doi: 10.23738/ccsj.150103 1. introduction before the health crisis induced by covid-19, lipstick was the best-selling make-up product. although wearing a mask has drastically reduced lipstick sales, it remains the quintessential feminine attribute. chanel is one of the world’s leading sellers of lipsticks. like all international cosmetics companies, its products are sold in every country where the brand is distributed. however, where cosmetics are concerned, the success of a product is linked to the whole marketing mix (advertising, media communication, packaging, brand impact, texture and performance complaints) but, above all, to the color on offer. therefore, chanel exhibits to its customers a wide range of shades with the aim of appealing to women from all cultures, in all age ranges and of every style. like all chanel’s make-up ranges, the lipstick lines are divided into two parts: firstly, a core range including iconic shades that are found all over the world, and secondly the freedom to use colors that respond to the needs and specific characteristics of the markets. we thought it would be interesting to study which were the 20 best-selling shades in each part of the world where chanel’s products are distributed. a couple of years ago, chanel offered 142 lipstick shades splitted over five ranges: 34 classic moisturizing lipsticks (rouge coco), 48 shiny, transparent lipsticks (rouge coco shine and rouge coco stylo), 39 intense lipsticks (rouge allure) and 21 matt lipsticks (rouge allure velvet). there are six regions of the world studied: france, italy, united kingdom, usa and asia (korea, japan, singapore, china and taiwan). the geographical areas studied are not of identical size because maison chanel compiles its figures by continent. in this article, the best-selling lipsticks were analyzed to determine color preferences by geographical area through pca methodology, to establish specificities of each market of the world and to understand similarities between the markets. the most similar geographical areas will thus be distinguished from the most dissimilar ones. 2. materials and methods 2.1. color measurement the color of the products was measured using an xrite vs450 contactless spectrocolorimeter in the ciel*a*b* color space. the color measurements were done in specular included mode, with a 45/0 geometry and a d65 illuminant. 2.2. statistical analysis a first mapping of the 142 shades available on all the markets was produced using a principal components analysis (pca) performed on the l*, a* and b* parameters (everitt, landau, leese and stahl, 2011). based on this summarised information, groups of shades were identified (figures 2 a, b and c). afterward, to regroup products with similar shades, a clustering method was applied on the previous pca components (jobson, 1992). a 2nd pca was carried out to determine the geographical similarities and regional benchmarks of the markets. a response surface model using standard least squares was used to analyse the ranking in a specific market. the main effects of the model are the lipstick rank and the second order the geographical area. the ranking of the 20 best-selling shades per country or continent at the end of the studied year was supplied by the company’s marketing division (chanel, 2016). these results are based on sell-in figures, except for asia where only sell-out figures were available. the product classified as number 1, the most frequently sold, will then have 20 points. the points assigned will then decrease to 1. a shade which is not present in the 20 best-selling shades in a given region will, therefore, have a mark of 0 as hhown in figure 1. the color classification previously built was used to determine the shades unanimously liked all over the world and those which are more favoured or even specific in a geographical area. fig. 1. extract of scoring matrix for lipsticks based on their classification out of the 20 best-sellers in each region. 20 = 1st in the classification. 0 = not mentioned in the classification. 3. results the lipstick color analysis is resumed on the figure 2.a. the first axis represents the a* and b* parameters. the lipsticks on the bottom left are darker. the one on the right are redder and yellower. the classification led to obtain 8 clusters. to visualise the classification, the previous graph was rebuilt using color of the lipstick and the shape corresponding to the classification. the figure 2.c is a focus on the 20 best-selling shades in the six regions. they are not always the same from one region of the world to another. therefore, 50 lipstick shades of the 142 offered by chanel are represented. a comparative study of lipstick shades preferences by geographical areas 21 color culture and science journal vol. 15 (1) doi: 10.23738/ccsj.150103 fig. 2. lipstick color classification analysis a. simultaneous representation of the first factorial map of the pca on the 142 lipsticks color parameters. b. graphic representation in the colorimetric space of the 142 shades offered by chanel. the shape corresponds to the lipstick colors classification. c. graphic representation of the 50 shades mentioned in the rankings of the six regions studied. figure 3 shows the distribution of the 50 lipstick shades mentioned at least once in the top 20 best-sellers in the 6 markets studied and in the different lipstick ranges. the color measurements established that these 50 shades represented the 8 clusters already established with the 142 lipsticks on sale worldwide. for these 50 shades we can see that all the measurements reported in the l*c*h* color space are in the first quadrant for hue h* between 0 and 45°, which logically corresponds to the space for reds. for lightness l*, they are between 5 and 70, with most lipsticks between 40 and 50, so with medium lightness figures. the greatest variability observed is in chroma c*. the range varies between 7 and 90 and is of course linked to the lightness of each shade. for both light and dark shades, we see lower chroma due to the geometry of the color space. the 8 clusters can be described as detailed. the 8 statistically defined groups are sometimes very close on one of the parameters l*a*b*c*h* and overlap. cluster 2 cluster 3 cluster 4 cluster 5 cluster 6 cluster 7 cluster 8 a b c cluster 1 a comparative study of lipstick shades preferences by geographical areas 22 color culture and science journal vol. 15 (1) doi: 10.23738/ccsj.150103 fig. 3. the 50 shades of the five ranges classified in the rankings of the six regions studied. the algorithm model chosen makes each shade appear in a given cluster, but it would have been possible for the shades on the borderline to be attached to a neighbouring cluster. cluster 1 corresponds to the darkest shades, also known as ‘nearly black’. only 2 shades out of the 50 mentioned among the top 20s for the various markets are in this cluster. the l* value is below 30. the chroma is low. cluster 2 includes 6 dark shades: dark, burnished or purplish reds, or burgundies. cluster 3 is the most represented with 11 shades. they all have medium lightness, around 50, and are unsaturated. these shades include antique pinks, faded reds and browns. there is only one shade in cluster 4. this shade is very light, saturated and has a red tinge. it is a light pink. cluster 5 contains 9 shades with medium lightness, slightly lower than cluster 3. they are quite saturated. cluster 6 includes 3 shades. they are light, with lightness above 50 and are quite saturated. cluster 7 is made up of 9 shades, like cluster 5. the lightness is medium, the shades are saturated and the chroma is red. this is the bright red group, ranging from true reds to reds with a bluish undertone. cluster 8 also includes 9 shades. they are of medium lightness, with high saturation and a red-yellow tone. they include salmon and orangey shades. 4. discussion the spectrocolorimeter measurements of the range are positioned in a limited space as the chanel lipstick range does not include atypical shades (yellow, green, blue) but is concentrated in the reds area (de clermont-gallerande et al., 2018). it is interesting to note that while numerous studies have been conducted on global color preferences, they have never focused on a color space as limited as a lipstick range (sakamoto, 2014). all the shades are relatively classic, even though some might seem extravagant, such as the very dark shades in cluster 1, as shown figure 4. the shades in cluster 3 are the most represented among the top 20 shades for each market, because they are number 11 out of the 50 shades listed in the classification. they, therefore, correspond to 22% of the shades classified in the various top 20s. clusters 5, 7 and 8 are of equal size among the 50 shades studied and each composed of 9 shades. it should be noted that these 3 clusters group together the saturated shades. two shades are classified among the top 20 of the six regions studied: rouge allure pirate and rouge coco gabrielle. however, the rankings of sales of rouge allure pirate are systematically better than those of rouge coco gabrielle, making rouge allure pirate chanel’s best international seller. rouge allure pirate was launched by chanel in 2005 and rouge coco gabrielle in 2015. the two shades are saturated dark reds with a hint of yellow. they are both in cluster 7, which gives the impression that this cluster represents lipstick shades which are appreciated whatever the culture and geographical area (premium beauty news, 2017). considering both the presence of the six regions in the ranking and their positioning within that ranking, the most frequently sold shades are rouge allure pirate, rouge coco stylo message and rouge coco gabrielle. rouge coco stylo message is in cluster 2. a comparative study of lipstick shades preferences by geographical areas 23 color culture and science journal vol. 15 (1) doi: 10.23738/ccsj.150103 fig. 4. classification of the 50 shades mentioned in the top 20 for the 6 studied regions in the 8 clusters. fig. 5. the score of the 50 shades most frequently represented of the top 20 in the six geographical regions, comparing their presence and ranking within that classification. fig. 6. presence number in the rankings of the top 20 in the six geographical regions. s h a d e c lu s te r 1 2 3 8 7 6 5 4 a comparative study of lipstick shades preferences by geographical areas 24 color culture and science journal vol. 15 (1) doi: 10.23738/ccsj.150103 six shades are present in five of the six regions studied: rouge allure velvet la favorite (cluster 8), rouge allure velvet la fascinante (cluster 7), rouge allure velvet la raffinée (cluster 5), rouge coco stylo message (cluster 2), rouge coco stylo histoire (cluster 8) and rouge coco mademoiselle (cluster 3). it is interesting to note that among those excellent sales, three are matt lipsticks. three shades are among the 20 best sellers in four regions: rouge allure passion (cluster 7), rouge coco arthur (cluster 8) and rouge coco stylo lettre (cluster 3). eight shades are represented in this ranking in three geographical regions: rouge allure velvet l’eclatante (cluster 6), rouge allure velvet rouge vie (cluster 2), rouge coco etienne (cluster 2), rouge coco marie (cluster 3), rouge coco shine boy (cluster 4), rouge coco stylo energie (cluster 5) , rouge coco style récit (cluster 2) and rouge coco stylo conte (cluster 6). eleven shades are present only twice in the top 20 ranking: rouge allure velvet la bouleversante (cluster 2), rouge coco cécile (cluster 3), rouge coco légende (cluster 3), rouge coco suzanne (cluster 2), rouge coco antoinette (cluster 3), rouge coco shine bonheur (cluster 5), rouge coco shine romance (cluster 5), rouge coco shine deauville (cluster 3), rouge coco shine monte-carlo (cluster 8), rouge coco stylo roman (cluster 5) and rouge coco stylo article (cluster 8). lastly, 16 shades are specific to one region: three shades are specific to france: rouge allure velvet l’amoureuse (cluster 3), rouge allure rouge noir and rouge allure elégante (both cluster 1). france is the only market that ranks shades from cluster 1 in its top 20. french women therefore show a specific preference for very dark, almost black, desaturated shades and deep purplish browns. in the case of italy, two shades: rouge allure velvet rouge charnel (cluster 7) and rouge allure velvet la bouleversante (cluster 2). even though the 2 shades are very different, it is interesting to note that italian women differ in preferring matt make-up results, as the 2 lipsticks that are specific to this market are matt formulas. italy also shows a preference for shades in cluster 7, with 6 of them ranked among the 20 best-sellers. cluster 7 includes red and bluish-red shades with medium lightness and high saturation. as for the united kingdom, two shades are noticed: rouge coco téhéran (cluster 6) and rouge coco adrienne (cluster 3). as the other european countries, uk is centrally positioned in the pca but its inclination is for american preferences. the 2 specific shades are of medium lightness and have reddish-yellow hints, with one orangey and one brown shade. the united states have a single specific shade: rouge coco maggy (cluster 3). the united states indicate their preference with an antique pink shade. the united states have a real preference for the shades in cluster 3, as they represent 7 of the 20 best-selling shades. cluster 3 includes somewhat darker shades, with medium saturation. more generally, the anglo-saxon countries prefer rosewood and nude shades. there are three specific shades to south america: rouge coco romy (cluster 5), rouge coco shine mighty (cluster 5) and rouge coco stylo script (cluster 3). this market appreciates shades with bluish tinges. there are, therefore, obviously 3 pink shades among their specific selection. however, while the 2 pinks in cluster 5 are very bright, the one in cluster 3 is desaturated. it is cluster 5, with its medium lightness, high saturation and pink and bluish red hue that is most widely represented among the 20 shades sold most on the market. fuchsia shades are appreciated in this region. interestingly, the asian market shows a real preference for the shades in clusters 7 and 8, which they are often the only market to prefer (saito, 1996). this is the geographical area where we find the largest number of specific shades, as 8 shades in the top 20 only appear in this market. all the shades in cluster 8 are present among the 20 best-sellers, i.e., 9 shades out of 20. cluster 8 includes the light to very light, highly saturated shades, with very bright colors. thus, asia is the most differentiated part of the world compared with the other geographical areas. it is distinguished by different color choices from those of the other markets studied. asians tend to prefer pinkish shades, while other parts of the world tend to prefer redder shades. however, although the preferences of france, italy and the united kingdom are relatively similar compared with other countries, differences can nevertheless be discerned between south america and the united states. south americans are inclined to prefer brown shades like rouge allure rouge vie while north americans tend to prefer reds. thus, similarities and countries whose choice of shades is very close can be observed (choungourian, 1968), (urien and divard, 2000). for example, italy and france share a preference for 13 of the 20 best-selling shades. there are mainly issued from clusters 2 and 3, which shows similar preferences for desaturated, brownish, intermediate lightness shades. asia and usa are the most distant with only 4 out of 20 shades in common. a comparative study of lipstick shades preferences by geographical areas 25 color culture and science journal vol. 15 (1) doi: 10.23738/ccsj.150103 table 1. number of shades shared by two regions of the 20 shades present in the ranking. the first criterion of similarity in the choices seems to be linked to geographical proximity. europeans share a preference for certain shades. as an illustration, italy and france share 13 of the 20 best-selling shades. the united kingdom shares 12 shades with italy and 11 with france mainly from clusters 3 and 5. similarly, countries whose culture is latin make similar choices in their shades and south americans and italians share 12 out of 20 shades, while france and south america share 11. lastly, there seem to be certain affinities between englishspeaking countries, although they are somewhat less marked. ten shades are shared by the united kingdom and the united states but also by south america, the united kingdom and the united states, a 50% similarity in all those cases. the part of the world which is really very different from the others is asia with a maximum of nine shades in common with another region, italy, sharing only four shades out of 20 with the united states. those two continents are the most distant in their shade preferences. the countries which best represent world preferences are those of europe, with france and italy in the lead, closely followed by the united kingdom. fig. 7. graphic representation of the 50 shades classified in the top 20 sells of the 6 markets. each point represents a shade. market information is superimposed on shade information. to study the color preferences in each region, the link between the ranking and the lipstick color classification was studied. the figure 5 is a cluster representation in the top 20 ranking according to geographical region. france is the only region which presents shades in cluster 1 in its 20 bestselling shades. italy shows a preference for cluster 7. despite the united kingdom is centrally positioned, like all european countries, its inclination is for american preferences. for the united kingdom and the united states, cluster 3 is most frequently represented in the survey of their best sellers. although south america shows a preference for cluster 5, a taste for saturated pinks suggests a degree of latin proximity to france and italy. lastly, asia is the most differentiated part of the world with a nearly 50% preference for light saturated shades (cluster 8). the specific shades which appear in a country’s ranking but not in the five other regions are shades characteristic of the country’s color preference. although the results of this study make it possible to highlight differences in colorimetric preferences according to the regions of the world, it should be borne in mind that chanel's customers may have a specific appetite for the shades offered by this brand. indeed, each company has a colorimetric "signature", related to the choices of the make-up artist of the house, the pigments referenced internally, the habits of the colorists of the research and development department, the marketing positioning of the brand etc (de clermontgallerande, 2021). fig. 8. cluster representation in the top 20 ranking according to geographical region. areas italia uk south america asia usa france 13 11 11 8 10 italia 12 12 9 8 uk 10 8 11 south america 6 10 asia 4 0 5 10 15 20 cluster 8 cluster 7 cluster 6 cluster 5 cluster 4 cluster 3 a comparative study of lipstick shades preferences by geographical areas 26 color culture and science journal vol. 15 (1) doi: 10.23738/ccsj.150103 5. conclusion the 50 best-selling lipstick shades in six regions of the world showed that the shade called rouge allure pirate, a satured red with medium ligthness was unanimously preferred internationally. the two most representative markets in terms of lipstick shades were italy and france. the markets of europe, france, italy and the united kingdom, were close in their choices while asia was the geographical region where the best-sellers were the most different from the rest of the world. lastly, a proximity in the choices of the latin countries and a tendency towards proximity for the english-speaking countries was apparent. the best-selling lipstick colors differ from one area to another. americans prefer pink or rosewood shades as do the british, while asians opt for very fresh, light and saturated shades. in south america, bluish and saturated shades account for good sales figures. each region shows its cultural difference through these color preferences. it would be interesting to repeat this analysis in few years on the same geographical regions to see if preferences remain stable or if they change over time. 6. conflict of interest declaration this research did not receive any specific grant from funding agencies in the public, commercial, or not-forprofit sector. 7. conflict of interest declaration the authors declare that there is no conflict of interest with other people or organizations. 8. short biography hélène de clermont-gallerande technological innovation manager at chanel. she has an experience of 30 years in color and make-up formulation and is inventor of more than 20 cosmetics patents. she published a collaborative book on sensorial cosmetic raw materials. emmanuelle mauger data scientist at chanel fragrance & beauty’s research center, in charge of data and their analyses to create insights. she achieved the statistical analysis of the study. nicolas rolland colorist in chanel color development laboratory for 8 years. previously, he worked at l’oréal also as colorist and has an expertise in color data management. licensing terms articles published in the “cultura e scienza del colore -color culture and science" journal are open access articles, distributed under the terms and conditions of the creative commons attribution license (cc by). you are free to share (copy and redistribute the material in any medium or format) and adapt (remix, transform, and build upon the material for any purpose, even commercially, under the following terms: you must give appropriate credit to authors, provide a link to the license, and indicate if changes were made. you may do so in any reasonable manner, but not in any way that suggests the licensor endorses you or your use, you may not apply legal terms or technological measures that legally restrict othersfrom doing anything the license permits. copyright: the authors keep the rights to further publish their contents where they want and can archive pre-print and post-print (submitted version and accepted version) and the published version of the pdf of their article with no embargo period. references chanel pb (2016) ‘sell in bases vente monde asie & ww projection sept 2016 // region feedback south america ytd sept 2016’ internal source. choungourian, a. 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(2017) https://www.premiumbeautynews. com/fr/rouges-a-levres-quelles-sont-les,11916 (accessed: 15 september 2021) ‘rouges à lèvres : quelles sont les préférences des consommatrices ? saito, m. (1996) ‘comparative studies on color preference in japan and other asian regions, with special emphasis on the preference for white’ color res appl, 21:35 https://doi.org/10.1002/(sici)15206378(199602)21:1<35::aid-col4>3.0.co;2-6 (accessed: 8 november 2021) sakamoto, k. (2014) ‘cultural influence to the color preference according to product category’, international conference on kansei engineering and emotion research. keer, linköping pp 1427-1434 https://www.semanticscholar.org/paper/cultural-influence-to-the-colorpreference-to-sakamoto/173dc6c4794e92c014f4a2e75f9988 bb00032336 (accessed: 8 november 2021) urien, b. divard, r. (2000) la prise ne compte de la dimension culturelle de la couleur dans le marketing international. available at : https://halshs.archives-ouvertes.fr/hal-00819321/ (accessed: 8 november 2021) cultura e scienza del colore color culture and science 39 cultura e scienza del colore color culture and science | 09 | 2018 issn 2384-9568 1mari uusküla mari.uuskula@tlu.ee 2martin eessalu eessalu@gmail.com 1tallinn university, school of humanities 2 independent researcher glossy black is not actually ‘black’: evidence from psycholinguistic colour-naming studies in 14 european languages abstract since berlin and kay’s seminal monograph, most studies on colour vocabulary and categorization have concentrated on the three main characteristics of colour – hue, lightness and saturation – which play a major role in the semantics of colour terms. this paper addresses a rarely discussed phenomenon, the appearance and naming of the surface of the colour stimuli, and argues that researchers should pay careful attention to possible unintended consequences when selecting their materials for psycholinguistic experimental (field) work. until recently, researchers have remained true to examining the main colour characteristics, not observing beyond, in spite of glaring evidence from some less-studied languages. native speakers of fourteen typologically diverse languages spoken in europe participated in two colour-naming experiments carried out with color-aid or munsell stimuli. having a single colour term black in the spotlight, the paper argues that glossiness might be an extra-linguistic feature which contributes to the semantic meaning of a colour term. according to the evidence gathered, black only seems to refer to a non-shiny, matte colour and has therefore been underused for glossy-surfaced stimuli in our datasets, resulting in a risk of elimination from the inventory of basic colour terms due to its low naming frequency and object-relatedness. keywords semantics, field methods, experimental methods, colour naming, cross-linguistic comparison, colour appearance citation: uusküla m. and eessalu m., (2018) ‘glossy black is not actually ‘black’: evidence from psycholinguistic colour-naming studies in 14 european languages’, cultura e scienza del colore color culture and science journal, 09, pp. 39-44, doi: 10.23738/ccsj.i92018.04 received 14 november 2017; revised 23 february 2018; accepted 10 march 2018 mari uusküla is associate professor of linguistics and translation theory at tallinn university, school of humanities. her research interests include semantic typology; colour naming, categorization and perception, field linguistics, and psycholinguistics. she has published research articles on colour semantics and categorization in a range of european languages including italian, russian, hungarian, finnish, czech and others. martin eessalu is currently an independent researcher, whose body of research includes musical instruments, ethnobiology and colour perception among others. the common denominator to bring the topics together would be psycholinguistics and human perception of objects and senses. 40 cultura e scienza del colore color culture and science | 09 | 2018 | 39 44 uusküla m. and eessalu m. issn 2384-9568 doi: 10.23738/ccsj.i92018.04 1. introduction it is widely known that colour consists of three main features – hue (or colour in non-technical english), saturation and lightness (biggam, 2012: 3-4). however, there are languages which do not build their colour vocabulary on these particular features, but concentrate on other aspects, such as surface texture or the impression of colour. despite the fact that these features have been discussed to a certain extent in the literature (conklin 1955), the wider audience still concentrates on hue, lightness and saturation, especially when stimuli are selected to carry out a (psycholinguistic) colour-naming experiment. the aim of this paper is to shed some light on other features of colour which carole biggam has classified as “other aspects of appearance” and “non-appearance aspects” (biggam, 2015: 5-6). bringing examples from various languages spoken in europe, this paper shows that certain aspects of colour affect the way the speakers of these languages perceive colours and talk about them. the purpose of the article is not to attack the theory by berlin and kay, as might be perceived, but to bring new understanding and fresh knowledge into the discussion on colour naming, where the emphasis is essentially placed on colour naming, appearance and semantics. the aim of this paper is to contribute to the general controversy of psycholinguistic colour research with an emphasis on a rarely discussed feature. we investigate the selection of colour stimuli shown to subjects during psycholinguistic (field) experiments, or more precisely, the surface of the selected stimuli. taking the category black as an example, we argue that the rather overlooked feature of surface is an important one and should be taken into account when choosing appropriate stimuli for psycholinguistic colour-naming studies. while carrying out psycholinguistic fieldwork on the estonian language within the project evolution of semantic systems (eoss) (majid, jordan, dunn, 2015), run and coordinated at the max planck institute for psycholinguistics, we observed that subjects had difficulties recognizing and naming glossy colour chips of the darker hues. more specifically, despite the fact that colour selection contained one black colour tile, there was a remarkable lack of consensus between subjects cross-linguistically, i.e. the glossy surface of a black stimulus caused misunderstandings and confusion in the colour naming task – the black tile was not actually named ‘black’ by participants as it was probably perceived differently. we replicated the eoss study with estonian subjects in 2015 keeping the exact study design and yet obtained the same results. if we analysed the germanic language data from the eoss project (courtesy of our colleagues, see acknowledgement) the same pattern could clearly be identified: in only a couple of languages from the germanic language group were the participants able to name the black stimulus with a relatively high level of consensus. by consensus we mean that at least 50% of the interviewees of one particular language named the specific stimulus using the colour term ‘black’. in the majority of languages the black stimulus was named differently. on the other hand, in a colour naming field experiment which was similar design-wise, but contained different stimuli based on the ostwald colour system, no similar issue could be identified. in every language, there was at least one stimulus which was constantly named ‘black’ with high consensus among the participants. we therefore conclude that some other aspects besides the hue of the stimulus may contribute to such a vast difference in colour naming between the two studies. leaving aside a minor dissimilarity in stimulus hue, the most notable discrepancy between the two sets of stimuli emerged in the matte vs glossy surface: coloraid tiles had matte surfaces, while the munsell set was glossy. 2. participants the languages chosen for this study constitute a convenience sample: we needed a reasonable amount of data for both munsell and color-aid corporation stimuli, and were able to retrieve the data for the languages listed in table 1. there is almost no overlap between the investigated languages, but as our goal was to exemplify a wider cross-linguistic phenomenon, we argue that the imbalance of the two groups was not an obstacle. group i data were gathered using color-aid corporation stimuli, while group ii data were collected using munsell stimuli. the results for germanic languages and their colour systems have been published in (vejdemo et al. 2014). the constitution of the two groups shown in table 1 is comparatively different: group i data (using color-aid stimuli) were gathered with the idea of keeping the internal structure of the language sample balanced in terms of age and gender. the amount of data per language was also (usually) larger. group ii (eoss data) language samples had younger mean ages as the target groups were undergraduate students with no particular knowledge of linguistics (majid, jordan, dunn 2015). nevertheless, nearly every language sample of group ii included some older subjects too. there is a slight possibility of a bias due to eoss studies normally having fewer subjects, but it is rather unlikely that the effect of bias 41 cultura e scienza del colore color culture and science | 09 | 2018 | 39 44 glossy black is not actually ‘black’: evidence from psycholinguistic colour-naming studies in 14 european languages issn 2384-9568 was responsible for the entire phenomenon we describe here. 3. stimuli and procedures two experimental methods were used to gather the data: the data for group i languages were obtained using the field method established by ian davies and greville corbett (1995); the data for group ii languages were gathered using a method devised by majid and levinson (2007). in the studies conducted with the field method established by davies and corbett (1995), the subjects were instructed to name all 65 colour stimuli that were presented to them one by one, placed on a neutral grey cloth. the order of the stimuli was random. the stimuli were 65 coloured papers from the color-aid corporation 220 set. these were glued on 5x5 cm plywood squares. the colour naming was fully unconstrained. participants’ answers were recorded or written down manually as said and were not analysed or shortened any further. color-aid uses a modification of the ostwald colour system, which incorporates three main characteristics: hue, blackness or shade, and whiteness or tint. colour-aid codes are read in the following manner: y stands for yellow, yoy stands for yellow-orange-yellow, s in a code represents shades as in y s2 (the scale is given from 1 to 3 where 3 indicates the darkest shades) and t represents tints, as in yoy t4 (the scale is given from 1-4 where 4 represents the lightest tints). in the field method developed by majid and levinson (2007) the participants were shown 84 munsell tiles in a single fixed random order where n2 was always preceded by 5y 4/6 and always followed by 10p 8/6. out of 84 munsell chips, four were achromatic: n2, n4.5, n7 and n9.5. the remaining 80 chips varied in hue, brightness and saturation, so that there were 20 equally spaced hues in four degrees of brightness (majid and levinson, 2007). saturation was generally at the maximum point. participants were asked to name all colours shown to them with appropriate colour terms. the study used an unconstrained naming method, all answers were recorded, written down and analysed. if participants offered compound words, only the second part of the compound was used for the later analysis in the original study. here we preserve and use all the data as originally offered by the subjects without further reductions. since the munsell colour system is widely known, we refrain from an in-depth description of it here. the analysis of the results is given with the assumption that color-aid black and munsell n2 are perceptually similar, and the main characteristic differentiating the two stimuli is the glossiness of the surface for munsell n2 stimulus. both studies were carried out in natural daylight avoiding shadow or exposure to direct sunlight. group language number of subjects f e m a l e s / males mean age (w/m) data collector group i finnish 68 42/26 39.5 (38.4/41.4) mari uusküla lithuanian 51 35/16 42.3 (40.5/46.3) simona pranaityte italian 102 56/46 38.6 (36.8/40.9) mari uusküla czech 52 33/19 34.7 (32.6/38.2) mari uusküla hungarian 125 66/59 35.6 (37.0/34.1) mari uusküla spanish 38 20/18 42.7 (49.2/35.5) kelly parker estonian 19 10/9 32.7(33.8/31.5) triin kalda group ii swedish 20 10/10 27.2 (24.8/29.6) susanne vejdemo estonian i 29 16/13 28.7 (27.1/30.7) martin eessalu, mari uusküla estonian ii 20 15/5 30.9 (n/a/n/a) liina kivimets english 20 9/11 22.3 (22.8/21.8) linnaea stockall swiss german 20 10/10 25.6 (26.9/24.3) martina zimmermann danish 20 11/9 26.5 (27.2/25.4) carsten levisen icelandic 21 10/11 29.0 (33.6/24.8) matthew whelpton, thorhalla beck german 20 10/10 21.1 (21.0/21.2) cornelia van scherpenberg norwegian 20 9/11 28.4 (26.2/31.1) aashild naess table 1 the sample of languages, the number of subjects, their mean age and female/male ratio. 42 cultura e scienza del colore color culture and science | 09 | 2018 | 39 44 uusküla m. and eessalu m. issn 2384-9568 doi: 10.23738/ccsj.i92018.04 the researchers were instructed carefully beforehand to ensure the comparability of the data. all participants were recruited volunteers. they were not introduced to the subject of the research until the beginning of the experiment in order to avoid priming effects. unfortunately we were unable to measure the coordinates of our stimuli in cie l*a*b*. 4 results and discussion table 2 shows the naming pattern for the black category in 14 languages with the black colour terms in the respective languages, and the overall naming frequency, the dominant frequency (both frequencies depend on the overall number of informants per language), the number of stimuli that were named ‘black’, and the specificity index first calculated by davies and corbett (1994). for technical details consult 1995 [3]. overall, the frequency measure includes the frequency of all the stimuli that were named with the colour term ‘black’. dominant frequency indicates the summed frequency of stimuli that were mainly labelled with the colour term ‘black’. dominant frequency is calculated taking into account the consensus of 50%, i.e. at least half of the participants had named that stimulus ‘black’ in their respective languages. specificity index (si), which essentially is a measure of proportion (varying between 0 and 1), was calculated in the following manner: dominant frequency divided by the overall naming frequency (davies and corbett, 1995). if the index value was 1, all participants named the stimuli with the same label, i.e. the colour term ‘black’ in their native language. if, however, the index value was 0, black was the label given to some stimuli, but it was not the dominant colour term for that particular stimulus (in our data n2 or black). in conclusion, the specificity index is a value showing the strength of a category, with overall frequency and the number of stimuli characterising the borders. table 2 shows that on one hand, group i languages had very little variation for naming black: nearly all tiles that were labelled with the colour term ‘black’ in their respective languages were dominant. if the number of the stimuli labelled as ‘black’ was 2, these two stimuli were always black and gray 8. any additional stimuli had very small naming frequencies. on the other hand, the munsell data in group ii languages rarely showed any dominant naming patterns whatsoever (excluding danish and swiss german samples). for example, if such colour naming data was used to establish the basic colour terms in a language, black could easily be excluded from the inventory of basic colour terms. this might evoke misunderstandings and serious problems in the basic colour term inventory of any language. according to the evolutionary sequence postulated by berlin and kay, black, together with white, should lexicalize among the first two colour terms in any language (berlin and kay, 1969). in the universality and evolution model (kay and maffi, 1999) the initial hypothesis was revised into white-warm and group language number of subjects colour term overall frequency dominant frequency number of stimuli “strength” of category group i finnish 68 musta 97 95 4 0.98 lithuanian 51 juoda 77 77 2 1.00 italian 102 nero 173 169 5 0.98 czech 52 černá 86 85 3 0.99 hungarian 125 fekete 185 182 5 0.98 spanish 38 negro 59 59 2 1.00 estonian 19 must 33 33 2 1.00 group ii swedish 20 svart 25 0 5 0.00 estonian i 29 must 24 0 5 0.00 estonian ii 20 must 14 0 4 0.00 english 20 black 14 0 5 0.00 swiss german 20 schwarz 37 13 7 0.35 danish 20 sort 42 33 5 0.79 icelandic 21 svartur 2 0 1 0.00 german 20 schwarz 4 0 1 0.00 norwegian 20 svart 13 0 4 0.00 table 2 the naming pattern of the black stimuli across fourteen languages 43 cultura e scienza del colore color culture and science | 09 | 2018 | 39 44 glossy black is not actually ‘black’: evidence from psycholinguistic colour-naming studies in 14 european languages issn 2384-9568 dark-cool categories. in table 2, we notice that the area of variation as measured by the number of stimuli was rather similar to group i data. as black had almost no dominance in the experiments using munsell stimuli (group ii), other colour terms occupied the area that could be expected to be called ‘black’. n2, the blackest stimulus of the data gathered with munsell stimuli, usually co-existed with grey. the modifier ‘dark’ was often added to ‘grey’ forming a morphologically complex expression ‘dark grey’. here, as implied before, we used raw data as gathered from our participants. many participants labelled the stimulus n2 with the following expressions instead of naming it ‘black’. for example, the estonian participants used hall ‘grey’ and tumehall ‘dark grey’; the swedish participants used mörkgrå ‘dark grey’; the english ones ‘grey’; the german ones dunkelgrau ‘dark grey’; the icelandic interviewees dökkgrár ‘dark grey’, etc. we were also interested in which other stimuli were called ‘black’ instead of munsell n2, and were able to notice that ‘black’ was extended to such stimuli as, for example, 5y 2/2 or 10y 2/2. however, ‘black’ was not the most commonly used colour term for either of them. the most dominant names given to 5y 2/2 were the estonian pruun ‘brown’ and tumepruun ‘dark brown’; the swedish brun ‘brown’ and mörkgrön ‘dark green’; the swiss german bruun ‘brown’ and dunku bruun ‘dark brown’; the danish brun ‘brown’, etc. intriguingly, the stimulus 10y 2/2, which veers towards the green area of the colour spectrum, was often named ‘dark green’, but also ‘dark brown’, e.g. swedish mörkgrön ‘dark green’, swiss german dunku grüen ‘dark green’ and dunku bruun ‘dark brown’, norwegian brun ‘brown’ and mørkebrun ‘dark brown’, and estonian tumeroheline ‘dark green’ and tumepruun ‘dark brown’. above we have shown the very narrow and consensual variation of black in color-aid studies (group i) and the blurry co-variation of black, (dark) brown and dark green in the munsell group studies (group ii). comparing munsell n2 and color-aid black (see table 2), we noticed that black was the conventionally established hue named as ‘black’. however, n2 was probably perceived differently by the participants due to its glossy surface, resulting in unexpected naming results. we therefore argue that glossiness is a feature that influences colour perception and contributes towards difficulties naming the colour stimuli in the darker regions of the colour body. this feature can be further illustrated by the example of car colours, as cars are often painted glossy: it is easier to detect and label the colour of lighter cars than the darker ones (anishchanka, 2013). 5. conclusion as shown by the empirical data analysis, we consider the semantic meaning of black to be extended to attributes such as the appearance of a surface. on the one hand, our study demonstrated that besides the black hue, the surface of the stimulus seems to play a certain role in seeing black tiles as black and labelling them with a colour term ‘black’ accordingly or, if the stimulus was glossy, participants had problems with naming it ‘black’. on the other hand, the speakers of many languages seemed to expand the colour term ‘black’ to encode darker colours in general (dark brown, dark grey, and even dark green or dark purple), perhaps with an etymological or analogical connotation with dirt or impurity, deriving historically from the distinction of latin ater vs niger ‘shiny black’. however, this hypothesis requires further indepth analysis. as seen from the results, the semantic meaning of black is quite restricted to rather matte colours. quite opposite results are obtained if glossy tiles are presented, providing much wider possibilities for interpretation. we therefore call on field linguists to carefully select their stimuli kits in anticipation of a probable bias in gathered results. nevertheless, it must be emphasised that the present study only focuses on black and some darker colours. there is no conclusive evidence to claim that the phenomenon could be extended to other colours. funding the research was partially supported by the estonian science foundation grant no. 8168 provided to mari uusküla between the years 2010–2013. conflict of interest the authors declare that there is no conflict of interest with other people or organizations. acknowledgements triin kalda collected partial estonian data using color-aid stimuli. liina kivimets replicated the eoss estonian part in 2015. kelly parker and simona pranaytitė collected castilian spanish and lithuanian data, respectively. we are thankful to our colleagues susanne vejdemo, linnaea stockall, martina zimmermann, carsten levisen, matthew whelpton, thorhalla beck, cornelia van scherpenberg and aashild naess for permission to analyse their data gathered for the eoss project. we would also like to acknowledge two anonymous reviewers for their helpful comments. 44 cultura e scienza del colore color culture and science | 09 | 2018 | 39 44 uusküla m. and eessalu m. issn 2384-9568 doi: 10.23738/ccsj.i92018.04 bibliography anishchanka, a..(2013)’seeing it in color: a usage-based perspective on color naming in advertising’, phd thesis, university of leuven. berlin, b. and kay, p. (1696/1991) basic color terms. their universality and evolution, berkeley. biggam, c. p. (2012) ‘the semantics of colour: a historical approach. new york: cambridge university press, 1–6. conklin, h. (1955) ’hanonoo color categories’ southwestern journal of anthropology, 11, 441–446. davies, i., corbett, g. (1994) ‘the basic colour terms of russian’, linguistics 32, 65-89. davies, i., corbett, g. (1995) ‘a practical field method for identifying basic colour terms’, languages of the world, 9, pp. 25-36. kay, paul, & maffi, luisa (1999). ‘color appearance and the emergence and evolution of basic color lexicons’. american anthropologist, 86, 65-79. majid, a., jordan, f. and dunn, m. (2015), ‘semantic systems in closely related languages’, language sciences, 49, pp. 1–18. majid, a. and levinson, s. c. (2007) ‘the language of vision i: color, field manual, 10. 90 color culture and science journal vol. 11 (1) review: two books that describe pigments and dyes, in a different and complementary way. renata pompas la fabbrica dei colori, pigmenti e coloranti nella pittura e nella tintoria. (the factory of colors, pigments and dyes in painting and dyeing). il bagatto, roma, 1986. (pages 578) this book, which was published with the cnr contribution, is the result of a group work, coordinated by the professors corrado maltese (chair of history of modern art) and franco salvetti (chair of general and inorganic chemistry), from the “la sapienza” university, of rome. it is a rich and complex text, divided into eight sections entrusted to different authors, who analysed pigments and dyes, described the materials, the production techniques, their history and application in painting and in textile dyeing. (including numerous examples of overdyes, or mixing of dyeing colors, to obtain the desired gradation, which debunk the myth of only-one dye substance used at a time). the sections  whites and blacks, by simona rinaldi, is divided in four sub-chapters. 1. from prehistoric times to the middle ages, the whites made from calcium carbonate. 2. rise and fall of lead white, from the classical age to the xix century. 3. the alternatives to lead white, from 1750 to today. 4. the black pigments in the history of painting. among the about thirty whites taken into consideration from the medieval ones, obtained from the shell of oysters and eggs, or marble, bones, etc..., to those of the xix century – we can also find their presence in some very famous paintings. of the black colors analysed it is described theirs processing technique starting from the prehistoric black carbon products.  reds, by giuliana quartullo, is divided into three sub-chapters. 1. the origin, manufacture and use of the red colour, from its appearance in history, to the first half of the xvi century. 2. the red color processing technique in the 15501700 period. 3. the red colour synthesized in the laboratory and in the painter's palettes, during the industrial age. the various reds colours and pigments are well described in their differences, including the best known, cited in various painting and dyeing treaties, such as: cinnabar, realgar, reds lands from madder, turkish red (much envied by napoleon), and kermes, also known as venetian scarlet.  browns and oranges, by annamaria milaneschi, is divided into three sub-chapters. 1. brown and orange pigments known since the antiquity. https://dictionary.cambridge.org/it/dizionario/inglese-italiano/the#_blank https://dictionary.cambridge.org/it/dizionario/inglese-italiano/the#_blank 91 color culture and science journal vol. 11 (1) 2. brown and orange pigments introduced between the xv and xviii centuries. 3. brown and orange pigments of industrial age. among the about twenty colors described, there are also: the ochre lands of prehistoric times, the tannins from roots barks leaves and different fruits, the bitumen processing, the "mummy” pigment, the orange of chromium, cadmium and antimony, up to the dyes of synthesis. in the part dedicated to the application of these products to painting, the author describes the damages suffered by some french paintings of the xix century, in which bitumen altered their surface with cracks, similar to sores.  yellows, by rita pietropaoli and annamaria milaneschi, analyses about twenty colors, included in three sub-chapters. 1. the origin, processing technique and use of yellow, starting from its presence in history, to the greeks and romans times. 2. the yellow in the middle age and renaissance age. 3. yellow after 1700, synthesized in laboratory and present in the industrial age palette. among the curiosities is interesting the history of the saffron and curcuma use, not just as fabric dyes, but also as pigments for miniatures and watercolours. a sub-chapter is dedicated to gold, both as precious mineral reduced in thin laminae or powder, as well as artificial inorganic pigment used in mosaic, called "purpurine, porporin or purpureus colour", perhaps because in the illuminated pages it was painted on a purple background.  greens, by susanna occorsio, is divided into three sub-chapters. 1. the origin, processing technique and use of green, from its appearance in history, to the first half of the xvi century. 2. the green processing technique during the 15501700 period. 3. the green synthesized in laboratory and present in the industrial age palette. among the about thirty greens analysed, many of them are included in the “verdigris” term; in addiction it is interesting to know that a green of synthesis was already produced in ancient mesopotamia and egypt.  ultramarine blue, by federica costantini scala. 1. the natural ultramarine blue. 2. the artificial ultramarine blue. among the curiosities the news that the “società di sviluppo per l'industria nazionale” (company of development for the national industry) in 1824 offered 6000 francs to those who were able to develop an industrial system to produce the artificial ultramarine blue, at a cost not exceeding 300 francs per kilo.  blue, by gabriella minunno, is divided into two subchapters. 1. from the origins to xviii century. the grinding of azurite, so much used by painters, is at the origin of different changes of shades of its hue: it darkens or veers towards the green, transforming itself into malachite, as it happened in so many medieval frescoes and oil paintings. the same problem occurred in with the "enamel blue", composed by a potassium glass grounded and mixed with oil, which was produced in venice with the name of "sapphire blue"; also this colour presents today important discolourations. a paragraph is dedicated to the "egyptian blue" and an other to the "maya blue". among the several names with which the woad dye was indicated, are mentioned recalled “vitrum, glastum, uvatum, guadum, guaro, pastello, falso indaco”. 2. pigments and dyes of the industrial age. many are also the names with which the "prussian blue" appeared on the market.  purple, by cinzia virno, is divided into five subchapters. this name is used to indicate a wide range of shades, from pink violet, to blue violet, including all intermediate passages. 1. the purple of the ancients. the paragraph analyses the extraction process from the different types of murex, and the falsifications obtained by the use of many colouring substances. 2. the purple among the classical age, the byzantines and the renaissance age. 3. other substances producing purple dyes. 4. the purple of the central america indians. of this sub-chapter is interesting the description of cotton hank dyeing process, respecting molluscs which weren't destroyed. 5. the modern purple. in addiction the book provides a rich documentation: each color is described with the different chemical compositions, terminologies and applications, and each chapter is concluded with a list of paintings, in which the colors analysed are present. 92 color culture and science journal vol. 11 (1) kassia st clair, the secret lives of colour. john murray / pinguin books, 2017. (pages 320). of this book i happened to buy first the original version, and then his translation into italian: atlante sentimentale dei colori. da amaranto a zafferano 75 storie straordinarie. (utet – dea planeta libri s.r.l., milano, 2018). the first surprise was when i compared the first three pages of the colours (the pantone color wheels) of the two editions: they are dull and flat in the italian edition, intense and three-dimensional in the english one, with obvious differences (see for example the brown). the translator – claudia durasanti – writes in the note that she had to solve the problem of the cultural and linguistic differences in the names of colours, like for example the term “purple”, that – she writes – for english people is a violet shade, but for italians is “red” (n.d.r.? red the definition: jakubmarian.com/difference-betweenviolet-and-purple “purple occupies the space between red and blu more closer to red, instead violet is more closer to blue”). she also mentions the case of the whitby's “jet black” used in english jewellery, that in italian she translates as “gaietto”: a term now in disuse. but let's come back to the book: the author describes 75 colors , corresponding to 75 headings monthly written by the author for the elle decoration magazine, in each of which the author describes a colour nuance. in addition to six introductory chapters: perceptionas we see the colours. an arithmetic matter – the light. the palette – artists and their pigments. vintage colours – a map to the nuances. chromophilia, chromophobia – the colour is political. colour in reality – does the language create the nuances that we see? the choice of the colors made by the author, seems to depend on their name, sometimes of scientific derivation (alizarin, cobalt, crocus sativus, etc...), sometimes of industrial derivation (prussian blue, fuchsia, etc...), other times historical (isabel, shocking pink, dutch orange, flea, etc...), or according to the name of the different materials (ivory, chalk, woad, etc...), or even imaginary name as italian name “buio” (n.d.r.?) in english “dark”. this is a book that has been very successful, it has been translated into 12 languages, including: spanish, german, chinese, russian, korean, dutch and romanian. it is treated also as a pleasant editorial "object", rich in anecdotes, curiosities and historical references, written in a fluid and pleasant way, that left me... a little confused. 64 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140108 modern methods for the visualization of lenticular film colors david pfluger1, lutz garmsen1, giorgio trumpy1, 2 1 department of film studies – university of zurich. david.pfluger@saeure.ch, info@oscilux.de 2 norwegian colour and visual computing laboratory – ntnu. giorgio@trumpy.eu corresponding author: giorgio trumpy (giorgio@trumpy.eu) abstract some of the first home movies shot in color used a 16mm lenticular film produced by kodak from 1928 to the late 1930s. this very special film stock called kodacolor is embossed with an array of hundreds of vertical cylindrical lenses that allowed recording color scenes on a black-and-white panchromatic silver emulsion. there are multiple possible methods to extract the color information from the film images. scanning the silver emulsion in high-resolution and letting a software extract the encoded color information represents an efficient method to obtain digital color images from these historical motion pictures. in this context, a new approach based on artificial intelligence has demonstrated to be more efficient for the localization of the lenticular screen than other previous methods. an alternative solution consists in digitizing the color images while these are created with the original optical method. while this last approach has the advantage of better representing the original historical appearance, it requires specific equipment and skilled operators. keywords lenticular film, kodacolor, color reconstruction, deep learning, film digitization received 31/10/2021; revised 04/01/2022; accepted 19/02/2022 modern methods for the visualization of lenticular film colors 65 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140108 1. introduction this paper presents and compares two novel approaches for reconstructing the color content of 16mm kodacolor lenticular film. the first approach uses artificial intelligence to localize the color information in the digitized silver emulsion and provides a new modern tool to access lenticular films in color. the second approach reconstructs the color with an optical method, separating the color components by means of a moving slit that sections the entrance pupil of the imaging system used for the digitization. the close analogy with the original projection setup allows to consider the latter optical reconstruction a positive color reference. 2. historical context of lenticular film since the birth of cinema in the mid 1890s, inventors and researchers set out to apply techniques of color photography to motion pictures. however, decades had to pass before a practical solution to record color information on motion pictures was developed. in the 1920s the industrial exploitation of ‘autonomous colors’ such as tinting and toning was at its climax (yumibe 2012), but at the same time a series of two and three-color photographic processes were trying to improve their results and finally enter the market. color processes based on temporal synthesis reunite color separations on the screen by displaying them in the same rapid succession as they have been recorded. the primary colors were added to the black and white separations either by filtering the projected light with a spinning filter wheel, as in kinemacolor (kindem, 1981), or by tinting the individual film frames, as in friesegreene (bedding, 1909). since the color separation images were taken at slightly different times, the reproduction suffered from pronounced color fringes around moving objects. the lenticular film process, on the other hand, produced three color separations taken at the same time, and recorded them in a single film frame. kodak was the only company that successfully produced lenticular film at an industrial scale. the film was marketed from 1928 under the name kodacolor. however, most of the inventions behind the process have been made before the company acquired the rights to exploit the technique (capstaff and seymour, 1928). the fundamental ideas behind the lenticular process for the photographic reproduction of colors can be found in the work done by liesegang before the turn of the century (ahriman, 1896) and by lippmann a few years later (lippmann, 1908). liesegang envisioned a ‘pixelated’ spatial encoding of colors with a perforated screen, while lippmann described in detail the structure of a lenticular film that would allow a better representation of reality. in the early 1900s berthon combined the two concepts and started endeavoring the application of the lenticular color process to moving pictures (berthon, 1910). in 1909 he patented a set-up including a tripartite red-green-blue filter as part of the imaging lens combined with a lenticular structure in front of the light sensitive panchromatic black-and-white film. the realization of this optical design had some major challenges. for instance, the lenticular structure engraved on the celluloid base defines the resolution of the image, so the lenticules had to be minuscule. for the technical implementation on an industrial scale, berton found the assistance of albert keller-dorian, who was the director of a company with expertise in engraving techniques (jacquet-loew, 1923). berton intended to produce a film with minuscule lenticules either in a honeycomb-like shape (fig. 1) or as a linear array (berthon, 1910). the keller-dorian-berthon process was patented in 1915 (keller-dorian and berthon, 1914) but the first world war delayed the development. the cooperation continued until the death of keller-dorian in 1924, resulting in no more than some short experimental shots. in 1926 a short film was successfully produced (ede, 2013). however, the scarce success of the financial investment forced berthon to sell the patents to kodak, who instead managed to develop the kodacolor film product in a comparably short time. fig. 1. a 35mm frame of a keller-dorian sample with a ‘beehive’ lenticular screen, visible in the underlying enlarged details. modern methods for the visualization of lenticular film colors 66 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140108 fig. 2. kodacolor lenticular film system – left: diagram describing the three stages of the lenticular color reproduction—shooting/processing/projection—for an ‘object’ represented by a red dot. right: front view of the processed photo-emulsion with superimposed stripes that indicate the location of the color separations. the result was a 16mm reversal film with a linear vertical lenticular screen, aimed at amateurs, which was released in 1928. agfa was working on a very similar product, called agfacolor, which was ready to hit the market in 1932 (eggert, 1932). however, no trace of any actual footage shot by amateurs could be found by the authors so far. the process was likely abandoned before its release. a widespread market success was necessary for a novel color technique to survive for a sufficient time and have a significant impact on the landscape of cinema. if a new color process allowed to use existent hardware for film recording and projection, it had more chances of success (jacquet-loew, 1923), while additional costs of specific equipment—that could become obsolete in a short period of time—would likely dissuade exhibitors and amateurs alike to adopt novel processes. also, the possibility of producing copies for distribution was an essential requisite for the success of a film technique (mitchell, 1951). kodacolor did not have these requirements, and it also had limitations in (i) image brightness—typical of all additive color processes—(ii) image detail and (iii) color gamut. after some success in amateur filmmaking, these limitations determined a quite sudden decline when a superior product was introduced by the same company. the introduction of chromogenic colors in the form of kodachrome was a game changer for the film industry, and all other existing color processes on the amateur market rapidly disappeared. a wide color gamut could be reproduced by kodachrome with subtractive synthesis, producing images with high level of detail using standard recording or projection equipment. therefore, lenticular film rapidly lost appeal and kodacolor disappeared from the market towards the end of the 1930s. 2. characteristics of kodacolor film the lenticular system is based on the possibility to partition the entrance pupil of the lens into three separate parts, given the fact that the whole area of the entrance pupil uniformly contributes to the image formation. additive primary colors (red, green, and blue) are assigned to each part using a tripartite color filter (fig. 2left). the camera lens focuses the image on the film and the color components are recombined, but their light arrives at the focal point from different directions. the tiny cylindrical lenticules focus the tripartite exit pupil of the camera lens on the film emulsion, so the color components expose separated areas of the film emulsion. in the 10 mm wide image area of the 16mm kodacolor film there are around 230 vertical lenticules. the motion picture was captured with the red-green-blue filter in front of the camera lens. the lenticules’ focal length corresponds to the film thickness. a camera equipped with a 15 mm lens and a f/2 aperture allowed the color components to expose the photographic emulsion separately (capstaff, miller and wilder, 1937). after exposure, reversal processing created positive silverbased images with spatially encoded color information: modern methods for the visualization of lenticular film colors 67 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140108 the silver densities associated to the red, green, and blue components lie side-by-side underneath each lenticule (fig. 2-right). the value of the color component is inversely correlated to the local amount of light-absorbing silver. fig. 3. kodacolor ad suggesting a setting for the appreciation of the films (movie makers magazine, 1928). in the original procedure, the colors of lenticular film were displayed with a regular 16mm projector equipped with a tripartite filter similar to the one used during shooting. the projection was rather dim, and it could be only shown to a few people in a small projection setting (fig. 3). nowadays, the original filter attachments for cameras and projectors are hard to find, and analog projection is a threat to the unique reversal originals due to shrinkage and fragility of the film material. it is therefore difficult to display these films with the original procedure. 4. numerical color reconstruction the transformation of the image content into digital form enables a viable way to make these movies available to the public, while at the same time it preserves the image content that is otherwise subject to decay due to the aging of the film material. an efficient approach to obtain digital color images from lenticular film is to scan the film in high-resolution—with the emulsion facing the imaging system—and let a software extract the encoded color information. in 2013 two independent works were presented in different fora (reuteler, fornaro and gschwind, 2013; aschenbach, 2013), the first of which was conducted in the framework of the snf project dolce at the university of basel. the software reconstructs the color accomplishing two main tasks: (1) the localization of the lenticular screen, and (2) the conversion of the side-by-side silver densities into rgb values. 4.1. localization of lenticules’ boundaries the lenticular screen is quite clearly discernible as a regular vertical pattern overlaying the photographic image (fig. 4-a). the numerical localization of the dark lines that mark the boundaries of the lenticules (fig. 4-b) is essential to find and allocate the color information from a monochrome emulsion scan. the automatic localization with signal processing is sometimes complicated. the lines are not necessarily perfectly vertical and straight already from the film fabrication or became damaged and warped due to aging. geometric distortions and defocusing might occur during scanning due to film misplacement or optical aberrations of the imaging system. in addition, the silver particles constituting the photographic image obscure the lenticular pattern in all dense areas of the image. the dolce software positively localizes the lenticular borders and efficiently reconstructs the colors in certain cases (reuteler and gschwind, 2014). however, when the above-mentioned complications are relevant, the proper localization of the lenticular screen is error-prone and often fails. fig. 4. the color reconstruction process – a: the input image. b: the lenticules’ boundaries. c: the position of the color components. d: the final color image. modern methods for the visualization of lenticular film colors 68 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140108 instead of seeking to improve the success rate by introducing additional parameters to the existing software and making it more flexible, it was found convenient to adopt a completely different approach. a database of successful reconstructions carried out by dolce was used to train a new computer algorithm called deepdolce (trumpy et al., 2021; d’aronco et al., under revision). the dataset of successful dolce reconstructions was treated with techniques of data augmentation, so the training makes deep-dolce able to handle the typical situations in which dolce failed. 4.2. from grayscale to rgb once the lenticular boundaries have been accurately localized, the gray levels of the monochrome image (fig. 4-a) have to be converted into color. this conversion is performed with a series of convolutions and pixel wise operations based on the spatial locations of the three color components (fig. 4-c). the proper location of the color components with respect to the lenticule boundaries have been determined by recreating the original optical setup for projection and shining white light “backwards” inside the projection lens. in this experimental setup, the macro digital image reported in fig. 4-c was captured from the emulsion side of the lenticular film. the extracted rgb values are assigned to all the pixels localized within the lenticule in the specific row (fig. 4-d), resulting in a pattern with horizontal stripes. the same ‘stripy’ pattern is also found in the images resulting from the optical color reconstruction. 5. optical color reconstruction an alternative approach to obtain the colors of lenticular film in digital form is to use an optical setup equivalent to the historical assembly. to perform the digitization directly, however, the color images must be focused on a much smaller area—corresponding to the image sensor—than the projection screen. the image structure of the color image captured in this configuration has the advantage of bearing a closer resemblance to the original projected image than the digital color reconstruction described in sec. 4. nevertheless, the significant differences between the modern and the historical setups must be considered. the historical setup requires a wide-open lens aperture (f/2), otherwise the light intensities of the lateral red and blue components get attenuated in comparison to the central green. the large aperture was also an advantage for the lenticular process both in recording—due to the limited film speed—and in projection—due to the limited image brightness. in the modern setup for digitization, a macro lens with a wide-open aperture may produce a significant longitudinal chromatic aberration, such that it becomes impossible to find a common focus for all colors. the problem caused by the chromatic aberration is solved with an approach that reconstructs the color by optical means, but it extracts the color components as separate images with the same spectral composition. instead of replicating the original process with the tripartite color filter and a digital color sensor—as depicted in fig. 5-a—a slit is used in front of the imaging lens, exploiting the fact that the color components of lenticular film are all black-and-white. the slit lets the light expose the sensor for one color component at a time, while the area corresponding to the other colors is covered. three monochrome images are captured in succession with the slit in the three different positions, as depicted in figs. 5-b. the digital images are assigned to their respective color channels (b1 to r, b2 to g, and b3 to b), so correct color images are obtained. there is no focal mismatch between the color channels, and the longitudinal chromatic aberration is excluded by using a narrow band light source. in addition, the described method has the advantage that the exposure of the three images can be optimized independently. however, the digitization speed is reduced compared to the classical approach (fig. 5-a), as three consecutive images have to be taken for each film frame. while carrying out the described scanning operation, an accidental property of the information recorded by the lenticular system was made evident. in line with early lippmann’s idea (lippmann, 1908), the horizontal difference in position between the blue and the red color channel produces a shift in perspective of the recorded image content. when the monochrome color separations are reproduced by assigning them to the left and the right eye respectively, the perceived image receives a moderate but clear stereoscopic effect. the lenticular process involuntarily records depth information which can be made visible today with stereoscopic visualization. modern methods for the visualization of lenticular film colors 69 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140108 fig. 5. representation (not in scale) of the digitization process of the optically reconstructed lenticular color. a: single image capture with a color image sensor and the tripartite color filter. b: triple image capture with a monochrome image sensor and a moving slit. 6. color correction in order to obtain digital colors that properly represent the original analog projection of kodacolor lenticular film, the images resulting from the digitization must be assigned to the proper rgb space. it is thus necessary to define the “kodacolor1928” rgb space, which is calculated from the transmittances of the original color filter for projection. transmission spectra were measured with a doublebeam spectrophotometer (shimadzu uv-1800) and colorimetric calculations (cie, 2005) were performed considering the 1931 cie 2° standard observer (cie, 2019) and the irradiance spectrum of a typical film projector (kinoton fp38), which was measured with a spectroradiometer (konica minolta cs-2000). the resulting cie xy chromaticity values of kodacolor1928 are r = [0.6991, 0.2900], g = [0.2569, 0.6687], b = [0.1399, 0.0704], and w = [0.2997, 0.3025]. the diagram in fig. 6 displays the cie 1976 ucs values (hunt and pointer, 2011) of kodacolor1928 in comparison with dcip3 (smpte, 2011), which is commonly used in digital cinema projection. in order to generate image files that convey the proper color information, the color values in the kodacolor1928 space are converted to a standard rgb space for correct visualization. the whitepoint of the lenticular rgb space (xyz = [0.991, 1, 1.315]) does not correspond to any standard whitepoint, therefore a chromatic adaptation transform (cat) is necessary (moroney et al., 2002). fig. 6. top: chromaticity values of kodacolor1928 space derived from the transmittances of the filter for projection (reported in the plot) in comparison with dci-p3. bottom: the five-step process for the color correction of digitized lenticular films. modern methods for the visualization of lenticular film colors 70 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140108 in view of the linear von kries model (brill, 1995), the adaptation scaling must be performed at the cone response level (lms), and therefore the color space conversion requires five steps, which are reported at the bottom of fig. 6. the colorimetric specifications of kodacolor1928 define the first 3-by-3 matrix, which provides the xyz values of the rgb input image (stepa). the conversion from tristimulus to cone response and back (step-b and step-d) are the 3-by-3 matrices of the ciecam02 color appearance model (moroney et al., 2002). the chromatic adaptation consists of the scaling factors resulting from the ratios between the lms values of the destination and provenance whitepoints (step-c). in the present work we chose dci-p3 as destination space, whose colorimetric specifications define the last 3by-3 matrix (step-e) (smpte, 2011). 7. results the results of the methods described in the previous sections are reported in fig. 7. fig. 7. digital images of a lenticular film frame with inset enlargement. 1: black-and-white scan of the film emulsion. 2: slit scan. 3a: output of deep-dolce. 3b: output of deep-dolce after color correction. 3c: merge of luminance from 1 and chrominance from 3b. the scan of the film emulsion (fig. 7-1) has an image structure that is characterized by the silver-based film grain and by the regular vertical pattern of the lenticules. in the color image resulting from the slit scan described in sec. 5 (fig. 7-2), the film grain is not visible, but the pattern of the lenticular screen is still evident. the image has a limited sharpness and the readability of the magazine title “die auslese” is reduced. the color image resulting from the digital reconstruction with deep-dolce described in sec. 4 (fig. 7-3a) has a very good readability, thanks to the effective interpolation approach developed by d’aronco (d’aronco et al., under revision) and to the attenuation of the lenticular screen pattern. the color correction described in sec. 6 (fig. 7-3b) enhances the reds, owing to the prominence of the kodacolor1928 space in the red region (fig. 6top). image 3b of fig. 7 has a high level of image detail and accurate colors, but it lacks the image structure given by the film grain and the lenticular pattern. this situation suggests applying a method to transfer the image structure of the black-and-white scan to the color image. the method can be borrowed from video technology, separating the luminance and the chrominance using the ycrcb color space (poynton, 2003). the extracted color information is converted to ycbcr, and the luminance channel y is replaced with the black-andwhite emulsion scan. this operation provides a ‘robust’ image structure to the image (fig. 7-3c) that can be found appealing when the image is visualized on a big screen. 8. conclusion the projection of lenticular film with the original historical equipment is nowadays difficult to implement. regardless of the approach adopted, the digitization of kodacolor deliver a result that necessarily deviate from the original modern methods for the visualization of lenticular film colors 71 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140108 viewing experience. a bright, sharp image can raise concerns in terms of restoration ethics (trumpy et al., 2018), but it must be considered that the original screenings of lenticular film were always of poor quality and the new digital version can trigger a rediscovery of precious amatorial footage. the close analogy between the original projection setup and the optical reconstruction described in sec. 5 allows to consider the colors resulting from the optical reconstruction a positive reference (fig. 7-2). deepdolce provides a new modern tool to access the color of lenticular films and the resulting colors are sufficiently close to the reference (figs. 7-3). the software is robust, successfully localizes the lenticular screen and provides convincing colors. as soon as the testing phase will be completed with more lenticular films, and the computational pipeline for final look of the reconstructed image is finalized, the software will be made available as an open-source project on publicly accessible repositories. 9. conflict of interest declaration no financial/personal interests have affected the authors' objectivity and potential conflicts do not exist. 10. funding source declaration the research is supported by the hasler foundation, which promotes information and communications technology for the well-being and benefit of switzerland as an intellectual and industrial center. 11. acknowledgment the present work leverages the fundamental concepts developed by rudolf gschwind and joakim reuteler, who initiated the dolce project. stefano d’aronco and jan dirk wegner offered their computer science knowledge to develop deepdolce. the research would not be possible without the trust and support from barbara flueckiger. special thanks go to the institutions and private collectors who provided the films used in the experiments: agentur karl höffkes, stiftung deutsche kinemathek, cinémathèque suisse, lichtspiel / kinemathek bern, ralf klee, haus des dokumentarfilms stuttgart. 12. short biography of the authors david pfluger holds a phd in physical chemistry. after working in cinema post-production, he entered the field of time-based media preservation. he has been part of several projects in the field of film and video conservation. in the current scan2screen research project he is part of the technical team developing a multispectral film scanner specifically aimed at the challenges of color film preservation. lutz garmsen filmmaker, media artist, designer, and lecturer for experimental and animated film. with a strong background in analog film and optical printing, since 2003 lutz started working on experimental film digitizers. since 2019 he collaborates with prof. barbara flueckiger to design, test and improve a versatile multispectral scanner. giorgio trumpy imaging scientist with solid experience in bridging the gap between art and science. his fields of expertise span from optics to spectroscopy, from colorimetry to image processing, from heritage conservation to visual arts. currently associate professor at ntnu and research scientist at the university of zurich. references ahriman (1896) ‘von der zukünftigen photographie. ein neues prinzip der farbenphotographie.’, photographisches archiv, 37, pp. 249–251. aschenbach, t. 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(2014) ‘die farben des riffelfilms. digitale farbrekonstruktion von linsenrasterfilm’, rundbrief fotografie, 21(1/2, 81,82), pp. 37–41. smpte (2011) ‘rp 431-2:2011 smpte recommended practice dcinema quality — reference projector and environment’, rp 4312:2011, pp. 1–14. trumpy, g. et al. (2018) ‘cyber-digitization. pushing the borders of film restoration’s ethics’, electronic media & visual arts, conference proceedings, 2018, pp. 190–195. trumpy, g. et al. (2021) ‘deep-dolce. a deep learning approach for the color reconstruction of digitized lenticular film’, in colour photography and film conference proceedings. colour photography and film: sharing knowledge of analysis, preservation, conservation, migration of analogue and digital materials, florence: associazione italiana colore, pp. 82–88. yumibe, joshua. moving color: early film, mass culture, modernism. rutgers university press, 2012. http://cie.co.at/publications/colorimetry-part-1-cie-standard-colorimetric-observers http://cie.co.at/publications/colorimetry-part-1-cie-standard-colorimetric-observers microsoft word 150109 69 color culture and science journal vol. 15 (1) doi: 10.23738/ccsj.150109 “perpetual plum”: colour naming strategies in maybelline’s lip products isabel espinosa-zaragoza1 1 english department, university of alicante, alicante, spain. isabel.espinosa@ua.es corresponding author: isabel espinosa-zaragoza (isabel.espinosa@ua.es) abstract this study deals with the particularities of “constructed nameables” (wyler, 2007, p. 117), that is, colour terminology in the context of cosmetic products, more specifically, of lipstick colour names by the cosmetic company maybelline. how these nameables are created (i.e. word formation processes) and the imagery exploited (i.e. themes) in order to be memorable in a competitive market are the focus of this study. for this purpose, a sample of four lipstick collections with a total of seventy-six shades is manually collected from their official webpage (www.maybelline.com). the analysis reveals the predominance of two nomenclatures: morphosyntactic and semantic. the former is intended to capture the consumer’s attention by deviating from the expected. this is carried out by means of both hyphenated expressions, such as pink-for-me, mauve-forme or plum-for-me, and with the use of the determiner more and secondary colour terms, like in more taupe, more magenta or more truffle, among others. the latter aims at seducing the customer by exploiting theme consistency based either on romance and compulsion (e.g. magenta affair, pink fetish) or on colour longevity (e.g. everlasting wine, eternal cherry). in some cases, these are also combined with alliteration (e.g. timeless toffee, continuous coral, perpetual plum) and assonance (e.g. steady red-y) to further appeal to the potential buyer. the results and conclusions point to the paramount importance of colour terminology in cosmetic verbal identity (allen and simmons, 2003). these colour names contribute to a coherent and homogeneous lip product range organisation that is highly memorable and attention-grabbing. keywords esp, colour terminology, verbal identity, naming, lipstick, cosmetics received 17/03/22; revised 03/10/22; accepted 31/10/22 “perpetual plum”: colour naming strategies in maybelline’s lip products 70 color culture and science journal vol. 15 (1) doi: 10.23738/ccsj.150109 1. introduction the cosmetic industry is known to resort to eye-catching verbal identities and, especially, evocative colour terminology, to differentiate quasi-identical products in an ever-increasing competitive market. the fact that both cosmetic products and brands are constantly created forces for the invention of impactful and memorable colour names to boost the appeal of the products offered. these colour terms are “constructed nameables” and, thus, “there is no reason not to use any lexeme as a colour designation, especially with cosmetics” (wyler, 2007, p.142). consequently, this colour terminology deserves close attention to determine which trends constitute the current verbal identity (allen and simmons, 2003) of, in our case, maybelline, and the potential intention behind such linguistic strategies. 2. the cosmetic industry: an overview the cosmetic industry is an extremely competitive market that has thrived even through global economic crisis both during the 20th and the 21st century (see merskin, 2007; hill et al., 2012; netchaeva and rees, 2016). in merskin’s (2007, p. 592) words, “lipstick sales have an inverse relationship with economic downturns and national calamity”. as a matter of fact, there is an economic indicator, what is known as “the lipstick effect”, which is described as the tendency to acquire relatively inexpensive beauty items or “affordable luxury” (see euromonitor international, 2013) during troublesome economic times due to psychological motives. namely, an instant gratification feeling after purchase, an improvement in consumer’s mood and an appearance enhancement that leads to an increase in positive selfesteem and social expression. according to kestenbaum (2017, para. 13), there is a generalised growth in beauty items expenditure, regardless of the product category. in fact, this economic sector is expected to grow in spite of the setbacks produced by the covid-19 crisis, with a shift towards hair dyes, skin care, nail care and others, that are ideal for at home pamper routines (see sedlmayr, 2022; mckinsey & company, 2021). regarding the different types of cosmetic brands, these could be organised according to their ceo or creator, like celebrity make-up brands and multinational corporations; their price point, such as drugstore, high-end or luxury brands (see espinosa-zaragoza, 2022); or depending on whether or not they are solely digital, like “digital brands” or digitally native vertical brands (dnvb), as opposed to those with traditional physical stores. the wide variety of brands currently available increases the competitiveness in the market and any detail like, for instance, the shade name in coloured products, is of paramount importance. these companies offer lipsticks in different formulas, finishes, colour ranges, prices, packaging and others. this has resulted in the production of countless similar lip products offering almost identical results and whose only difference may be the name given to the colour. concerning the name elements in cosmetics, these have their particular structure and consist of different constituent elements or parts. following tuna and freitas (2015, p. 136), cosmetic names are often made of three constituent elements: (1) the brand name, that identifies the company; (2) the product line, also called range or collection; (3) and the generic product name or function expressed by means of a description. for example, the “maybelline super stay 24® 2-step liquid lipstick makeup”, consists of the brand name (e.g. maybelline), the product line (e.g. super stay 24) and the generic name (e.g. liquid lipstick) also indicating its dual application stages (e.g. 2-step). to this structure or these already mentioned parts, others could be added, like the (4) colour name and the (5) descriptions (see espinosa-zaragoza, 2022). more specifically, the name given to identify the shade within the collection (and the brand), which is precisely the object of this study, and the optional description provided by the company in case the name is semantically opaque (e.g. milan, natalie) or if the brand wants to provide more information about an already transparent colour name (e.g. pink, berry). 3. colour terminology and verbal identity colour terminology may be divided into basic colour terms, henceforth bcts, (see berlin and kay, 1969) and secondary colour terms (see casson, 1994). on the one hand, bcts —black, white, red, green, yellow, blue, brown, purple, pink, orange and grey in english— are not usually resorted to in cosmetic colour terminology owing to their basic nature and lack of attention-grabbing properties (see wyler 2007, p. 116-117). these are, therefore, normally accompanied by diverse linguistic information referring to and describing its dimensions, like saturation and lightness (e.g. light, dark, deep), yielding compositional non-basic colour terminology (see anishchanka, speelman and geeraerts, 2014). on the other hand, secondary colour terms (see casson, 1994), also known as “non-compositional non-basic names” (see anishchanka, speelman and geeraerts, 2014) or “logical terms” (see biggam, 2012, p. 50), are denominations where the “entity stands for entity’s color”. like in, for instance, chocolate to name a brown shade that resembles chocolate. these are very prevalent in marketing, although they could be felt as insufficient to stand out among the myriad of alternatives in this highly competitive market. as a consequence, more linguistic “perpetual plum”: colour naming strategies in maybelline’s lip products 71 color culture and science journal vol. 15 (1) doi: 10.23738/ccsj.150109 information is often included to produce original evocative terms (biggam, 2012, p. 50). additionally, different “nominal architectures” (see martín, 2009, p. 283; wheeler, 2009, p. 22), that is, the identifiable patterns and relations in the naming of products, subproducts and services in a company, are applied to devise not only a coherent and homogeneous in-brand colour range organisation but also to increase the company’s appeal power as a means to stand out from the rest of competitors. thus, the creation of a brand identity helps in differentiating similar products. this advertising language is in search for attention value, readability, memorability and selling power which may be reached through a carefully considered verbal identity, more exactly, by the ideation of thought-out collections. among the different nomenclatures put forward by martín (2009), the most important for our purpose are the semantic and syntactic ones. in addition, phonetic-phonological aspects like alliteration and assonance, linguistic devices very much used in both poetry and marketing (see vasiloaia, 2009), are often applied rigorously, and, in turn, could be considered as another type of nomenclature (see espinosa-zaragoza, 2022). accordingly, a consistent and homogeneous brand image is apparent in the selected maybelline ranges, which contributes to memorability, both in terms of retention and recall power as well as in product differentiation (see skorupa and dubovičienė, 2015). 4. objectives and methodology this paper focuses on the verbal identity selected for the lipstick shade names by the cosmetic brand maybelline, paying attention to how these names are formed (i.e. wordformation processes), their themes and imagery exploited to appeal the consumer and other phonetic-phonological aspects present in them. consequently, the main objective is to identify and describe the different verbal identity traits in maybelline’s lip product lines. collection nomenclature n color sensational® made for all lipstick syntactic 7 color sensational ultimatte, slim lipstick makeup syntactic 10 super stay 24® 2-step liquid lipstick makeup semantic 44 color sensational® shine compulsion lipstick makeup semantic 15 total 76 table 1. sample information for our purpose, a sample of seventy-six colour names by the cosmetic brand maybelline (www.maybelline.com) was manually collected during march 2021. these shades belong to the four collections specified in table 1. it must be pointed out that no additional colour description was provided by maybelline at the time of the compilation, only a visual colour representation (i.e. picture and colour swatch). 5. analysis and discussion the analysis reveals the homogeneous utilisation of nomenclatures across collections based on (1) structure repetition which replicates patterns (i.e. morphosyntactic nomenclature) and (2) a consistent theme or topic in which every colour is part of a semantic field belonging to either colour longevity or romance (i.e. sematic nomenclature). moreover, some phonetic-phonological aspects are also intentionally exploited (i.e. assonance and consonance) so as to further appeal to the consumer with fancy sounding colour names. 5.1. morphosyntactic nomenclature concerning structure repetition in colour naming, two different word formation processes are consistently applied in two of maybelline’s lip colour ranges. on the one hand, in the “color sensational made for all lipstick” collection (1), hyphenated expressions are selected to reinforce the collection’s claim made in the collection name (i.e. made for all) and the general appropriateness of this particular colour for the customer (e.g. red-for-me, pinkfor-me; mauve-for-me, fuchsia-for-me; plum-for-me, spicefor-me; ruby-for-me). in this way, the colour name is addressing the person, indicating that this specific colour is perfect, appropriate and suitable for the consumer. this structural pattern (i.e. “colour term-for-me”) is a compound phrase with a colour term as head and a prepositional phrase complement (see bauer and renouf, 2001, p. 103). not only does this work as a mantra in each product application by stressing that this particular colour belongs to the consumer, but it also links and identifies those shades as part of the “made for all” collection. (1) color sensational® made for all lipstick: a) pink-for-me b) red-for-me c) ruby-for-me d) mauve-for-me e) fuchsia-for-me f) spice-for-me g) plum-for-me “perpetual plum”: colour naming strategies in maybelline’s lip products 72 color culture and science journal vol. 15 (1) doi: 10.23738/ccsj.150109 (2) color sensational ultimatte, slim lipstick makeup a) more berry b) more ruby c) more scarlet d) more magenta e) more blush f) more mauve g) more buff h) more taupe i) more rust j) more truffle on the other hand, the “color sensational ultimatte, slim lipstick makeup” collection (2) utilises a determiner (e.g. more) and a secondary colour term to convey that there is more of something, in this case, a secondary colour term (i.e. “entity stands for entity’s colour”). the secondary colour terms preceded by more belong to different semantic fields like flowers and plants (e.g. more mauve), food and beverages (e.g. more berry, more truffle), minerals and pigments (e.g. more ruby, more rust, more scarlet, more magenta) and animals and its fur, skin or feathers (e.g. more taupe, more buff, more blush). 5.2. semantic nomenclature according to martín (2009), a semantic nomenclature entails thematic consistency, in other words, following an identifiable conceptual pattern across all the products or services in a brand or, in our case, the colour names in a lipstick collection. there are two collections that follow a semantic nomenclature in our sample. firstly, the “super stay 24® 2-step liquid lipstick makeup” collection (3) heavily exploits the concept of product longevity: not only is it mentioned in the collection name (i.e. super stay 24), which claims to last up to 24 hours, but also in the colour name of the products. this is done in order to emphasise the long-lasting nature of these liquid lipsticks intended to stay on your lips for hours. to yield nameables including this homogeneous and constant reference to longevity across all shades, the structural pattern usually consists of either adjectives (e.g. everlasting, eternal, endless, infinite, unlimited, boundless, constant), adverbs (e.g. all day, 24/7, all night, forever) and a colour term, either basic (e.g. pink, red) or secondary (e.g. wine, cherry, chestnut and others). some examples are gathered in (3) below. in addition, there are some instances of sentences, like pink goes on or keep up the flame, that also indicate that the shade is long-lasting and even one instance of “colour term + noun”, merlot armour. in the latter, the colour is presented as a firm and enduring shield. as can be seen from the examples provided below, the notion of colour durability is maintained throughout all the collection shade names by using different adjectives and adverbs which highlight the high staying power of these lip products. (3) super stay 24® 2-step liquid lipstick makeup: a) never ending pearl b) absolute taupe c) constant toast d) all night apricot e) frosted mauve f) infinite petal g) always heather h) forever chestnut i) blush on j) crisp magenta k) frozen rose l) 24/7 fuschia m) all day cherry n) eternal cherry o) everlasting wine p) optic ruby q) unlimited raisin r) all day plum s) boundless ruby t) endless expresso u) pink goes on v) on and on orchid w) keep up the flame x) keep it red y) merlot armour (4) color sensational® shine compulsion lipstick makeup: a) baddest beige b) undressed pink c) secret blush d) spicy sangria e) spicy mauve f) risky berry g) steamy orchid h) arousing orange i) pink fetish j) taupe seduction k) chocolate lust l) scarlet flame m) magenta affair n) berry blackmail o) plum oasis secondly, the “color sensational® shine compulsion lipstick makeup” collection (4) focuses on love and romance (see merskin, 2007; radzi and musa, 2017; espinosa-zaragoza, 2022), especially on compulsion which is mentioned in the collection name. thus, this theme is resorted to with a two-fold aim: seducing the consumer so as to purchase these colours and, in turn, s/he also becoming the object of seduction. “perpetual plum”: colour naming strategies in maybelline’s lip products 73 color culture and science journal vol. 15 (1) doi: 10.23738/ccsj.150109 on the one hand, the semantic nomenclature is mainly carried out via compound adjectives (4a-4h) whose head is a colour term, either basic or secondary, and the modifier is an adjective related to sex and romance. thus, the sex-related information is conveyed with the left element in the compound, such as in, undressed pink, spicy sangria, spicy mauve, steamy orchid, risky berry, baddest beige, arousing orange and secret blush. on the other hand, it is also done by means of a colour term as a modifier in a compound noun (4i-4o) whose head carries the meanings related to passion, desire and a risky and forbidden love. examples of these types of shade names are pink fetish, taupe seduction, scarlet flame, chocolate lust, magenta affair, berry blackmail and plum oasis, as shown above in (4). 5.3. phonetic-phonological aspects apart from the previously mentioned consistent and homogeneous nomenclatures, there are some apparent phonetic-phonological aspects in these ranges, although not in every single shade name. therefore, it is not a nomenclature in this particular case, even though it could be considered another type of nomenclature as posed in espinosa-zaragoza (2022). these phonetic-phonological aspects are found in the “super stay 24® 2-step liquid lipstick makeup” collection (5) which, apart from being based on the notion of colour endurance, is also combined with consonantal alliteration in almost 40% of the collection. the objective here is boosting the attractiveness of this product, where the initial consonant sounds in both elements of the compound coincide. this can be observed in the repetition of consonantal sounds (5a-5m), especially of the voiceless plosive stops such as /p/ in so pearly pink and perpetual plum, /t/ in timeless toffee and /k/ in committed coral, constant cocoa and continuous coral or in the voiced plosive stop /b/ boundless-berry. the different approximants consonantal sounds are also repeated in compounds, like the voiced alveolar approximant /l/ in loaded latte and lasting lilac, the voiced post-alveolar approximant /r/ in reliable raspberry and relentless ruby and the voiced bilabial velar /w/ in wear on wildberry. lastly, the voiced bilabial nasal /m/ is also repeated in more & more mocha, as well as the voiceless alveolar fricative /s/ in stay scarlet. (5) super stay 24® 2-step liquid lipstick makeup: a) so pearly pink b) perpetual plum c) timeless toffee d) committed coral e) constant cocoa f) continuous coral g) boundless-berry h) loaded late i) lasting lilac j) reliable raspberry k) wear on wildberry l) more & more mocha m) stay scarlet n) extreme aubergine o) non-stop orange p) steady red-y q) very cranberry nevertheless, this initial sound repetition in the elements of the compounds, although mainly employed through consonantal sounds, is not exclusively relegated to them. in fact, there are also some instances of vowel sound reiteration (5n-5q), in other words, assonance, with repetition of /i:/ in extreme aubergine (/ɪkˈstriːm ˈəʊbərʒiːn/) or /ɒ/ in non-stop orange (/ˌnɒnˈstɒp ˈɒrɪndʒ/). furthermore, longer sound clusters like /ɛdi/ in steady redy (/ˈstɛdi ˈrɛdi/) and /ri/ very cranberry (/ˈvɛri ˈkrænbəri/) include the repetition of several consonantal and vowel sounds. it must be noted that the wordplay red-y coincides with the homophone “ready” but yielding a colour at the same time. 6. conclusions and final remarks this study highlights the importance of colour terminology in the cosmetic industry as part of the verbal identity of a company. thus, cosmetic colour names in general, but specially in lipsticks, do much more than simply describe or designate hues: these “constructed nameables” instil lip products with a distinctive touch that helps relating them to their brand and also serve as an organising tool where all the colours in a collection are named in a coherent and homogeneous way in hopes of capturing customer attention. these cutting-edge linguistic trends that currently dominate cosmetic colour denomination are worth analysing so as to know what has already been done and the possibilities still available for captivating and original colour terminology curation. on the one hand, with a repetition of structure patterns, the intention behind this verbal identity is to surprise the consumer by diverting customer expectations of finding a selection of conventional monolexemic colour terminology —either bcts (berlin and kay, 1969) or secondary colour terms (casson, 1994)—. in this way, eye-catching syntactic structures are searched for, which further contribute to collection memorability and homogenisation. on the other hand, the thematic consistency across ranges (e.g. longevity or romance) reinforces information that is already stated in the collection name. “perpetual plum”: colour naming strategies in maybelline’s lip products 74 color culture and science journal vol. 15 (1) doi: 10.23738/ccsj.150109 in this way, everything is connected and information which might influence a purchase is reinforced. on the subject of the use of romance as a theme in cosmetic colour names (see espinosa-zaragoza, 2002), there is a patent ambivalence with the customer both seducing and being seduced. that is, it is utilised with a two-fold intention: (1) the consumer is captivated by the colour range and, thus, seduced and/or enamoured by it and/or (2) the person that wears the shade is able to seduce others owing to the application of that particular colour to their lips. additionally, and in sum, alliterative compound colour names add to this experience as they are pleasing to the ear. some phonetic-phonological aspects, namely consonance and assonance, are also found in the sample. these are helpful rhetorical devices in an advertising context due to their fancy-sounding qualities and ability to increase memorability (see skorupa and dubovičienė, 2015) and also, in some cases, even constitute nomenclatures (see espinosa-zaragoza, 2022). this analysis further complements and expands on previous cosmetic advertising studies and on the language of cosmetics (see merskin 2007; ringrow 2016; radzi and musa 2017). these results are based on a reduced selection that does not capture the wide variety of colour naming strategies used in the cosmetic industry. this could be counteracted by adding other maybelline collections and even other brands to enlarge the colour name sample. nonetheless, the results and conclusions point to the crucial importance of verbal identity in cosmetic companies. the ideation of marketing-driven colour terminology is part of the verbal identity of a brand, which combined with other advertising elements, like pr packaging design, colour palette selection, brand ambassadors and social media (re)presentation and interaction, create an entire personality that differentiates the company from its competitors. we actively encourage the continuation of studies focused on colour terminology in advertising, not only in the cosmetic industry but also in other industries and economic sectors. 7. conflict of interest declaration the author of this piece of research declares no known conflict of interest with other people and/or organisations. 8. funding source declaration the author of this paper is the beneficiary of a grant from the vicerrectorado de investigación y transferencia de conocimiento/vice president for research and knowledge transfer of the university of alicante for predoctoral training (from 01/01/2019 to 04/05/2022). this research has been carried out with the financing obtained in the context of this grant. 9. acknowledgments i would like to thank the vicerrectorado de investigación y transferencia de conocimiento/vice president for research and knowledge transfer of the university of alicante for the pre-doctoral training without whom this research would not have been possible. 10. short biography isabel espinosa-zaragoza – holds a phd in linguistic studies from the university of alicante. her main research interests lie primarily in the field of colour names in marketing, paying attention to their (non)transparency and potential effects on consumers. she has participated in different national and international conferences (e.g. pics 2022, aic 2021) and published articles mainly covering the naming of colour in cosmetics. licensing terms articles published in the “cultura e scienza del colore -color culture and science" journal are open access articles, distributed under the terms and conditions of the creative commons attribution license (cc by). you are free to share (copy and redistribute the material in any medium or format) and adapt (remix, transform, and build upon the material for any purpose, even commercially, under the following terms: you must give appropriate credit to authors, provide a link to the license, and indicate if changes were made. you may do so in any reasonable manner, but not in any way that suggests the licensor endorses you or your use, you may not apply legal terms or technological measures that legally restrict othersfrom doing anything the license permits. copyright: the authors keep the rights to further publish their contents where they want and can archive pre-print and post-print (submitted version and accepted version) and the published version of the pdf of their article with no embargo period. references allen, t. and simmons, j. 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(eds) speaking of colors and odors. amsterdam/philadelphia: john benjamins, pp. 113–128. doi: 10.1075/celcr.8.06wyl cultura e scienza del colore color culture and science 75 cultura e scienza del colore color culture and science | 07 | 2017 | riccardo falcinelli “cromorama. how color changed our gaze” issn 2384-9568 renata pompas l’argomento colore conosce ultimamente un grande interesse da parte del pubblico, sollecitato da numerosi articoli (si pensi alla rubrica “sfumature” pubblicata settimanalmente dal quotidiano la repubblica) pubblicazioni varie e libri. riccardo falcinelli, visual designer e professore di psicologia della percezione presso la facoltà isia di roma, ha scritto illustrato e impaginato in otto anni di lavoro un libro originale nel contenuto e nella confezione: il testo è accompagnato nella banda verticale dai richiami bibliografici, le nota sono a piè di pagina, l’apparato figurativo si presenta sotto forma di composizioni di dettagli di immagini diverse, accostate per suggerire confronti e assonanze. il corposo testo (470 pagine) è suddiviso in quattro parti i cui titoli sono poetici, piuttosto che sistematici. • “parte prima sguardi”, introduce l’argomento cardine del libro su come il nostro sguardo sul colore cambi nel tempo in relazione alla società. comprende tre sottocapitoli: “giallo industriale. la società del design”. “rosso unito. l’occhio del xxi secolo”. “nero articolato. possibilità del colore industriale” i cui argomenti variano dalla moderna normalizzazione e serializzazione industriale del colore in opposizione agli effetti dinamici del colore preindustriale, dalle tecniche grafiche di sovrastampa usate nell’illustrazione, alla costruzione dell’immaginario cromatico dei consumatori. • “parte seconda storie”, comprende otto sottocapitoli. “azzurro costoso. coloranti e pigmenti prima review riccardo falcinelli, cromorama. how color changed our gaze. einaudi stile libero extra, torino, 2017. the topic of color recently evokes great public interest, prompted by several articles (as the weekly column “shades” of the newspaper la repubblica) various publications and books. riccardo riccardo falcinelli, visual designer and professor of psychology of perception at isia university in rome, after eight years of work, wrote, illustrated and made the layout of his book, original in its content and packaging: the bibliography is displayed in a vertical band along with the text, the footnotes are in the footers, 76 cultura e scienza del colore color culture and science | 07 | 2017 | pompas r. issn 2384-9568 della modernità” illustra la storia di alcuni pigmenti e degli artisti che ne facevano uso. “porpora simbolico. idee e miti del mondo antico” parla di ricettari e relazione tra la materia colorante e il suo simbolismo. “indaco spettrale. l’epoca delle rivoluzioni” ricorda i diagrammi di colore, l’opposizione tra le teorie fisiche di newton e quelle fenomenologiche di goethe, la fortuna del libro di chevreul e le applicazioni che ne fecero i pittori dell’epoca. “blu bovary. vestirsi per amare e per significare” indaga sul significato recondito del blu in letteratura. “malva modernità. la nascita del consumo e del divismo” narra la diffusione della moda del viola e del lilla e la commercializzazione dei colori a olio in tubetto rivolgono l’attenzione all’influenza delle mode sui comportamenti e i consumi. “verde illegale. la favola dei primari” descrive le differenti mescolanze di colori che nel tempo, concludendo che “non esistono i primari in sé, giacché non si tratta di valori naturali, ma di una mera convenzione tecnologica e culturale”. “ciano litografico. breve storia delle tecnologie cromatiche” mostra come l’evoluzione della tecnologia della stampa, della fotografia e delle pellicole filmiche a colori, abbiamo mutato lo sguardo sui colori del pubblico. “grigio armonico. grandi ideali per la vita quotidiana” confronta le teorie sull’armonia cromatica che ritiene rifiutino indirettamente il relativismo culturale del pensiero moderno. • “parte terza artefatti”, comprende anch’essa otto sottocapitoli. the figurative apparatus takes the form of compositions of different image details, matched to suggest comparisons and assonances. the full text (470 pages) is divided into four parts whose titles are poetic, rather than systematic. • “part one looks” introduces the book’s key topic as how our view of color changes over time in relation to society. it includes three subchapters: “industrial yellow. the society of design”. “solid red. the eye of the 21st century”. “articulated black. possibility of the industrial color” whose subjects range from modern normalization and industrial color serialization in contrast to the dynamic effects of pre-industrial color, the overprinting graphic techniques used in the illustration, and the construction of the consumer’s chromatic imagination. • “part two stories”, includes eight subchapters. “expensive blue. dyes and pigments before modernity” illustrates the history of some pigments and the artists who used them. “symbolic purple. ideas and myths of the ancient world” tells about recipes and relationship between color matter and its symbolism. “spectral indigo. the era of revolutions” recalls the color diagrams, the opposition between newton’s physical theories and goethe’s phenomenological ones, the luck of chevreul’s book and the applications made by painters at that time. “blue bovary. wearing to love and to signify” investigates the hidden meaning of blue in literature. “mauve modernity. the birth of consumption and stardoms worship” tells the spread of purple and lilac trend and the oil painting tubes marketing, focused on how trends influence behaviours and consumption. “illegal green. the fable of the primary colors” describes the different color mixing over time, concluding that “there are no primary colors in themselves, because they are not natural values but a mere technological and cultural conventions”. “marrone neuronale. come il cervello costruisce il colore” si focalizza sulle scienze cognitive e l’elaborazione psicologica del colore. “viola spezzato. la luminosità e le tinte” distingue la luce come “qualità dello spazio” dalla luce come “qualità delle tinte” nelle arti visive, le teorie della prospettiva cromatica e della luminosità delle ombreggiature. 77 cultura e scienza del colore color culture and science | 07 | 2017 | riccardo falcinelli “cromorama. how color changed our gaze” issn 2384-9568 “lithographic cyan. brief history of chromatic technologies” shows how the evolution of printing technology, photography and color motion picture film, have changed the way people look and see the colors. “harmonic gray. great ideals for daily life” compares the theories on chromatic harmony that, according to him, indirectly reject the cultural relativism of modern thought. • “part three artifacts” also consists of eight subchapters. “neuronal brown. how the brain builds color” focuses on cognitive sciences and the psychological processing of color. “broken violet. brightness and hues” distinguishes light as “space quality” from light as “hues quality” in visual arts, the theories of the chromatic perspective and the brightness of the shadows. “simultaneous sky blue. the fundamental chromatic contrasts” recalls the seven color contrasts of itten, theorizing and proposes to gave them two more names: “chromaticity contrast” (between a single color and black and white) and “pair contrast” (between two solid hues, flat and homogenous colors that contend the field with equal dignity). “significant red. the colors of things” analyzes the narrative aspects of color by distinguishing the function of “role” (the position within a system) and of “symbol”. “sour green. the to drink and to eat colors” denies the universal properties of synesthesia whose semantics is, first of all, activated through memories and analogies. “colonial beige. and other marketing issues” analyzes the color function of making a brand memorable and acting as product customization. “moral white. today’s myths, born yesterday” tells the contrast of color and non-color in cinema, photography, and television. “green vertigo. the woman who lived twice” analyzes the meaning of the narrative contrast of ruby red and emerald green in hitchcock’s movie. “celeste simultaneo. i contrasti cromatici fondamentali” riprende i sette contrasti di itten e ne aggiunge altri due che propone di chiamare: “contrasto di cromaticità” (tra un singolo colore e il bianco e nero) e “contrasto di coppia” (tra due tinte unite, piatte e omogenee che si contendono il campo con pari dignità). “rosso significante. i colori delle cose” analizza gli aspetti narrativi del colore distinguendo la funzione di “ruolo” (la posizione all’interno di un sistema) e quella di “simbolo”. “verde aspro. colori da bere e da mangiare” smentisce l’universalità delle proprietà sinestetiche dei la cui semantica funziona innanzitutto per ricordi e analogie. “beige coloniale. e altri problemi di marketing” analizza la funzione del colore di rendere memorabile una marca e agire come personalizzazione dei prodotti. “bianco morale. miti d’oggi, nati ieri” racconta la contrapposizione del colore al noncolore nel cinema, nella fotografia, nella televisione. in “verde vertigine. la donna che visse due volte” analizza con cura il significato della contrapposizione narrativa di rosso rubino e verde smeraldo nel film di hitchcock. • “parte quarta percezioni”, comprende 5 sottocapitoli più l’epilogo. “arancio bollente. vedere la temperatura” partendo dall’analisi cromatica di alcuni famosi film, ne analizza la temperatura cromatica e quella emotiva. “turchese registrato. il copyright sulle percezioni” affronta il nuovo problema del possesso di alcune sostanze coloranti, tramite brevetto. “rosa pesca. il problema dell’incarnato” analizza il conflitto tra “colore articolato” (composto da più gradazioni e tridimensionale) e tinta unita a cui l’industria cerca di sopperire con le finiture. “blé omerico. un’ipotesi per la percezione” partendo da quanto scritto da gladsone sull’assenza del blu in omero, conduce una riflessione sulla possibilità di 78 cultura e scienza del colore color culture and science | 07 | 2017 | pompas r. issn 2384-9568 •“part four perceptions”, includes 5 subchapters plus the epilogue. “boiling orange. see the temperature”, starting from the chromatic analysis of some famous movies, analyzes chromatic and emotional temperature. “registered turquoise. the copyright on perceptions” faces the new problem of possessing certain coloring substances, by patent. “peach pink. the problem of the incarnate” analyzes the conflict between “structured color” (with several gradations and threedimensional) and solid color to which the industry tries to compensate with finish. “homeric blé. a hypothesis of perception”, starting from what gladsone noticed about the lack of the color blue in homer, leads to reflection on the possibility of naming the colors. “yellow judah. technology and look” associates the colors with the material they are conveyed by and up to the bright colors, deep and shiny of the screen we are daily in touch with. the “epilogue”, lastly, summarizes the thesis of the whole book: if modernity has tried to standardize colors, on the other hand, it is not possible to standardize the gaze, which depends on the time and place, history and society. at this last part follow two appendices, which deal with “scientific concepts” and “principal chromatic models”. the iconographic note, the iconographic list, the bibliography. falcinelli writes about his own work: “this is not a historical essay but a narrative (...) the history story of our modern gaze, and how it is formed.” i think that falcinelli (1973) has published a full text written and illustrated with a fluid narrative flow and with the typical “back and forth” style, son of the digital revolution. nominare i colori. “giallo giuda. la tecnologia e lo sguardo” associa i colori al materiale con cui sono veicolati, e sino ai colori luminosi, carichi e brillantissimi degli schermi con cui siamo quotidianamente in contatto. “epilogo” infine riassume l’assunto di tutto il libro: se la contemporaneità ha cercato di standardizzare i colori non è invece possibile standardizzare lo sguardo, che dipende dal momento e dal luogo, dalla storia e dalla società. a questa ultima parte seguono due appendici, che riguardano “i concetti scientifici” e i “principali modelli cromatici”. la nota iconografica, l’elenco iconografico, la bibliografia. falcinelli scrive di questo suo lavoro: “questo non è un saggio storico ma un racconto (…) la storia del nostro sguardo moderno, e di come si è formato”. io penso che falcinelli (1973) abbia edito un testo corposo scritto e illustrato con un flusso narrativo ininterrotto e con un andamento back and forth figlio della rivoluzione digitale. cultura e scienza del colore color culture and science 80 cultura e scienza del colore color culture and science | 06 | 2016 | pompas r. issn 2384-9568 food, colour and art while the presence of the five colours (red, green, yellow, white, black) and of the five tastes (bitter, sweet, salty, sour, spicy) in a meal is a sign of a balanced and healthy diet in eastern cuisine, there is no equivalent tradition in the western world. however, the general public and many artists too have recently focused more and more on the colours of food. in 1997, french artist sophie calle was inspired by a text by writer paul auster for her work known as “le régime chromatique” (“the chromatic diet”), consisting of six photographs of monochromatic meals she ate for six days. each photo portrayed a monochromatic table setting with food of the same colour, along with the relevant menu caption: monday orange, tuesday red, wednesday white, thursday green, friday yellow, and saturday pink. the seventh photograph depicted all these colourful meals on a black background. two recent books categorise food by colour. renata pompas la cucina dei colori (“the kitchen of colors”. tecniche nuove, milano, 2011. “the kitchen of colors”) results from the cooperation of four authors: daliah giacoma sottile for the texts, nicola michieletto for the recipes, federica bottoli for the photographs, and arianna marchetti for food styling. it includes accurate and sophisticate images that form a sort of visual hypertext. the idea to design a chromatic diet came when daliah giacoma sottile studied the texts of french doctor jean valnet, who is considered the father of contemporary phythotherapy and aromatherapy, and the studies on colours by wolfgang goethe and rudolf steiner. as she was interested in chromotherapy, daliah giacoma sottile came to believe that food too should follow chromatic rules and designed eighty recipes with chef nicola michieletto in order to explore a variety of vegetable ingredients classified into five colours: black, white, yellow, green, and red. these are further divided into bright tones to be used from morning to lunchtime, versus dull tones to be used in the second half of the day. for instance, watermelons, strawberries, tomatoes and peppers are ‘bight red’, whereas beetroots, pomegranates, and beans are ‘dull red’. review 81 cultura e scienza del colore color culture and science | 06 | 2016 | review. food, colour and art issn 2384-9568 coloribo. colori da mangiare e cibo multisensoriale (“coloribo. colors to eat and multisensory food”. mario adda editore, bari, 2012) is the work of artist bice perrini, who transformed the natural ingredients of apulia, her homeland, into colourful sauces to be used to “paint” food with a brush in “multi-sensory food-painting” workshops. ‘coloribo’ is a combination of the italian words ‘colore’ (colour) and ‘cibo’ (food). originally it was the name of a performance by bice perrini at the galleria bluorg in bari, it has now become a brand known for its tagline ‘eating with eyes’, dealing with food production and sale, catering, food tasting, workshops, and art events. bice perrini wrote: ‘the inputs of colours, smells, tastes, and sounds are the gateways that allow the universe to come into us and to make us feel precious emotions’ and she invited us to ‘experience food as a work of art’. ‘coloribo sauces’ are served with bushes and come in seven colours: yellow, green, red, orange, violet, white, and black. the book also suggests some flavours to be used on a specific day of the week: white and blue on monday to start off, yellow on tuesday to step up, orange on wednesday to keep up, violet on thursday to reflect and go on, green on friday to be more confident and hopeful, red on saturday to get ready for action, and pink on sunday to relax. this blend of food, colours and art shows eastern and western cultural influences. microsoft word 150106 42 color culture and science journal vol. 15 (1) doi: 10.23738/ccsj.150106 an experimentation on children’s colour preferences in generic terms and applied to a school context camilla giani1, cristina boeri1 1 color lab, department of design, politecnico di milano, italy. milly.giani@hotmail.it, cristina.boeri@polimi.it corresponding author: camilla giani (milly.giani@hotmail.it) abstract the aim of the paper is to present an ongoing study on the evaluation of children’s colour preferences in the school context. in particular, two experiments have been planned and partially conducted in order to evaluate both the differences that may be found between colour preferences expressed in generic terms and contextualized in a school environment, and the differences that may be found between digital simulations displayed on the computer and experimented using the cave technology. the paper presents the methods of the two experiments and the results of the first experimentation conducted on children between the ages of 6 and 10 using an online questionnaire that showed children both digital colour samples and digital colour simulations of the same colours applied to a classroom environment. keywords colour design, colour preference, school design, children colour preference received 30/03/22; revised 30/12/22; accepted 30/12/22 an experimentation on children’s colour preferences in generic terms and applied to a school context 43 color culture and science journal vol. 15 (1) doi: 10.23738/ccsj.150106 1. introduction several authors have highlighted the importance of colour in school environments in relation to both functional and emotional values, also offering indications regarding the colours and schemes to be adopted (birren 1969, mankhe 1998, grube 2014, engelbrecht, 2003). in the framework of the studies about the evaluation of the emotional response to colour in children, and therefore on children’s colour preferences and associations, some experiments were conducted by circumscribing these evaluations to specific contexts. in these studies, simulations of differently coloured interior environments are subjected to the evaluation of children instead of generic or abstract colour samples. in particular, the studies by read and upington (2009) and dalirnaghadeh (2016) assessed children's colour associations and preferences in preschool interiors using the image of a school environment manipulated to create different colour alternatives. in the study by park (2014), the correlations between colour attributes and children’s colour preferences for interior room colours were analysed using scale-models. these studies contribute to the discussion regarding the role of the context in which the emotional response to colour is evaluated and therefore the possible design implications related to the study of colour preferences and associations in children. on the other hand, the limits linked to the simulation of reality and its simplification, even in monochromatic terms, raise the need for more circumstantial studies and research to concretely guide the design choices (boeri, 2019). in this framework two experiments have been planned and partially conducted in order to evaluate both the differences that may be found between the colour preferences expressed in generic terms and contextualized in a school environment, and the differences that may be found between digital simulations displayed on the computer and experimented using the cave technology. 2. methods the study focused on the design of two experiments for the evaluation of children’s colour preferences in a general and contextualised situations using digital simulations of a primary classroom environment. both the experiments were designed to involve children (age 6-10) in the evaluation of a selection of 26 colours firstly showed just as digital colour samples and then applied to digital simulations of the same classroom using a 3d model to be experienced in monitor for the first experimentation and in a cave for the second one. cave technology will allow the display of a 360 ° image of the classroom created as a 3d model. the model used for the simulation consist in a traditional classroom of 25 children set up with desks, chairs, wardrobe and shelves. the furnishings used have a graycoloured metal structure and natural coloured beech wood seats, backrests and shelves (figure 1). fig. 1. the classroom view used in the study. different colours were applied exclusively to the walls in a monochromatic solution of the classroom environment, which means all the walls were coloured with the same colour. this solution has been used in several studies both to verify the psycho-physiological effects of single colours (hettiarachchi and nayanathara 2017; kwallek et al. 1996; kwallek and lewis 1990), and to probe colour preferences related to a specific environment (read and upington, 2009; dalirnaghadeh, 2016). the colours selected were decided on the base of their recurrence in the literature addressing the children’s colour preferences taking into consideration the belonging to the same age group (6-10 years), and the adoption of material coloured sample for the methodology of investigation (child et al., 1968; boyatzis and varghese, 1994; terwogt and hoeksma, 1995; hettiarachchi and nayanathara, 2017). these colours are: red, blue, green, yellow, purple, pink, orange, and as achromatic colours white, black and gray. as specific colour notations relating to the colour samples adopted in the previous studies considered were not always available, the selection of the samples was carried out using ncs natural colour system. the chromatic colours, except pink, were chosen with maximum chromaticness, i.e. the sample closest to the apex of the ncs colour triangle. in addition, for each hue two additional samples were selected in order to obtain a lighter and darker colours option. even for the gray colour two more samples were selected with different blackness. an experimentation on children’s colour preferences in generic terms and applied to a school context 44 color culture and science journal vol. 15 (1) doi: 10.23738/ccsj.150106 thus, the total number of samples selected for the study was 26 (figure 2). fig. 2. the 26 ncs standard colours identified for the experimentations. at the top the high chromaticness colours followed by the lighter and darker colour options. once the colours were identified, the walls of the classroom image were modified using photoshop software, in order to obtain one classroom chromatic configuration for each colour, and then 26 different colour configurations of the same classroom to be evaluated. 3.1. experimentation i the first experimentation aimed to collect and evaluate preliminary data on abstract and contextualized children’s colour preferences using digital colour samples and digital colour simulations of classroom environments to be compared with each other and with the reference studies. the experimentation consisted in the administration of an online questionnaire to school-age children, between the ages of 6 and 10, of both sexes. the questionnaire was designed to be easy for the child to understand and to fill out quickly. one of the main advantages of using the online questionnaire is the ease in reaching a large number of subjects in a short time. on the other hand, the supervision of children delegated only to parents and not done by an expert, may either not be sufficient, or on the contrary, be too intrusive, affecting the children's responses (punch, 2002). the questionnaire was divided into two main macro sections, and preceded by the request to complete some general information about the children age and gender. the first section of the questionnaire focused on the investigation of abstract colour preferences. in the first question children were asked to specify the preferred colour among those shown: yellow, orange, red, purple, blue, green, pink, white, black and gray. the options to choose from for this question are presented all together, but in a random order, automatically generated by the google form. the participant was given the opportunity to provide only one answer to the question. despite the awareness that colours displayed on unknown and different devices would be different from those identified in the preliminary phase, the form presented visual reference of all colour samples, together with a corresponding colour name, to create a subsequent comparison with the same colour applied in the classroom environment. in the second question of this section, children were asked to assign a grade for each colour (from 1 to 4, where 1 is the lowest and 4 the highest), in order to create a ranking of preference. this method allows to gather more information on the same subject regarding not only the preferred colour, but also to all the other samples (guilfort and smith, 1959). in the third question children were asked to further express their preference on the colour they already chosen as the favourite in comparison with two more samples of the same hue and different blackness and chromaticness that would appear lighter and darker. the second section of the questionnaire was about colour preferences applied to classroom images. the structure of this section was the same as the previous one. children were asked firstly to choose their preferred coloured classroom among those shown, then to assignee a grade for each coloured classroom image (from 1 to 4), and finally automatically directed to the question that involved the coloured classroom they already chosen as the favourite in comparison with two more variants that would appear lighter and darker. the period in which data were collected was from april 2020 to may 2020. thanks to the collaboration of the teachers, the answers were given by children attending five different primary schools of lombardia region in italy. specifically, the number of children who participated in this experiment was 101, of which 53 were females and 48 were males. the children’s average age participating in the survey was 8.5 years. 3.2. experimentation ii the second experimentation, not yet conducted, involves the use of cave technology to simulate both abstract colours and the context of colour preferences. the colours and the 3d representation of the classroom used in this experimentation are the same as those illustrated previously for the first experimentation (figure 3). the cave (automatic virtual environment) of the ed-me lab laboratory for environmental design and multisensory experiences, of the politecnico di milano, is used for the experimentation. the simulation of this cave an experimentation on children’s colour preferences in generic terms and applied to a school context 45 color culture and science journal vol. 15 (1) doi: 10.23738/ccsj.150106 is semi-immersive, through the use of three synchronized projection screens. the projected images are not stereoscopic. the screens on which the image is projected are touch and therefore allow an interaction between the image and the viewer in the cave. furthermore, it is also possible to reproduce sounds and interact vocally with the cave system. the structure of the questions addressed to children is the same as the first experimentation. the differences are in the physical presence of the children participating in the trial and in the smaller number of children involved. the results obtained from this second experimentation will be compared with those of the first experimentation in order to evaluate the different degrees of control over the accuracy in digital colour reproduction as well as to estimate the effects of children’s involvement. fig. 3. the cave (automatic virtual environment) of the edme lab, politecnico di milano, used for the experimentation. 4. results the results of the first experimentation allow us both to understand if the colour preferences expressed by children in abstract terms using digital colour simulations are consistent with the results of the reference literature, and to understand if the preferences for the abstract colour are consistent with those expressed for the digital simulation of the class. with regard to colour preferences expressed in generic terms, the answers to the questionnaires were analysed both as a whole and on the basis of the age and gender of the participants. the most preferred colour was blue. this result appears consistent with child et al. (1968) and terwogt and hoeksma (1995). the colours with the lowest preference scores were orange, black and gray, that was also found in boyatzis and varghese (1994) and hettiarachchi and nayanathara (2017). no child has chosen white as their favourite colour. the percentages of preferences attributed to each colour with respect to the entire sample of children (101) were: blue 20.8; red 17.8; purple 13.9; yellow 13.9; pink 10.9; green 9.9; black 5.9; orange 5.9; gray 1. the analysis of the responses on the basis of the number of females and males who participated in the experimentation (53 females and 48 males) showed, as already emerged in other studies (ellis and ficek, 2001; hurlbert and ling, 2007), a gender difference in colour preferences (figure 4). the preferred colour for females was purple, while for males blue, as it was found in boyatzis and varghese (1994). fig. 4. abstract colour preferences referring to the number of females and males who participated in the experiment (53 females and 48 males). the analysis of the responses on the basis of the children’s age who participated in the experiment, highlighted, as already emerged in other studies (garth and porter, 1934; boyatzis and varghese, 1994; terwogt and hoeksma, 1995; zentner, 2001) a greater number of preferences for warm colours in children of 6-7 years compared to other age groups where more marked preferences for cold colours emerged. the preliminary results of this first part of the experiment, aimed at evaluating colour preferences in generic terms using digital colour visualizations, show consistencies with respect to the studies taken into consideration that used material colour samples (child et al., 1968; boyatzis and varghese, 1994; terwogt and hoeksma, 1995; hettiarachchi and nayanathara, 2017). moreover, the results of the first experiment allow us to understand whether the colour preferences expressed by children in general have been confirmed or not once applied to the classroom context. the percentage of children who expressed a different colour preference in an experimentation on children’s colour preferences in generic terms and applied to a school context 46 color culture and science journal vol. 15 (1) doi: 10.23738/ccsj.150106 relation to the differently coloured classroom displays was 54 percent (of which 58% were males and 52% were females). comparing the preferences given for each colour in the two situations (abstract and applied to the class image) in relation to gender (figure 5), we can observe an increase in preference for pink in males and an increase in preference for blue in females. furthermore, white appears more appreciated in both males and females when contextualised. even preferences for black are increased when contextualised compared to preferences for the abstract colour. fig. 5. preferred abstract and contextualised colours for females and males. a further comparison with respect to the lightness parameter given for each colour (figure 6), shows how in the contextualized situation there is an increase in appreciation for the lighter variation of the colour chosen as the favourite. therefore, we can say that preferences for the contextualized colours appear both different and more diversified compared to abstract colour preferences. fig. 6. preferred abstract and contextualised light-dark options of the favourite colour for females and males. 5. conclusion the aim of the study is the evaluation of children’s colour preferences in general and contextualised situations using digital simulations. the two experiments had the common purpose of probing the children's colour preferences, both abstract and contextualized, and to identify any differences among the two. although it is clear the difference between the digital simulation of an environment and the experience of a real environment, there are many advantages offered by the possibility of using the digital simulation to understand if and how the colour preferences in children can be affected by the contextualization in specific and different contexts. therefore, this study aims to use digital simulation with varying degrees of control over accuracy in colour reproduction as well as varying degrees of realistic feeling of environment and children’s involvement, in order to contribute to explore the design implications of colour preferences and associations. 6. conflict of interest declaration the authors declare no conflict of interest related to this publication. 7. funding source declaration this research did not receive any specific grant from funding agencies in the public, commercial, or not-forprofit sector. 8. acknowledgment the study presented in this article was the subject of a master thesis in interior and spatial design, school of design, politecnico di milano, by camilla giani — entitled the experimentation of children’s colour preferences in a school context — under the supervision of professors mario bisson and cristina boeri. 9. short biography of the authors cristina boeri architect, phd, she deals with the perceptual and design aspects of color, combining design, research and educational activities. since 2001 she has been carrying out and coordinating teaching and research activities at the color laboratory, department of design, politecnico di milano. since 2013 she has been adjunct professor of color and perception at the school of design, politecnico di milano. she is co-founders and current president of the color placemaking association. an experimentation on children’s colour preferences in generic terms and applied to a school context 47 color culture and science journal vol. 15 (1) doi: 10.23738/ccsj.150106 camilla giani graduated in interior and spatial design at the politecnico di milano in 2020 with a master's thesis the experimentation of children’s colour preferences in a school context under the supervision of professors mario bisson and cristina boeri. since 2020 she has collaborated with the color laboratory of the politecnico di milano for the development and advancement of her work started with her thesis. licensing terms articles published in the “cultura e scienza del colore -color culture and science" journal are open access articles, distributed under the terms and conditions of the creative commons attribution license (cc by). you are free to share (copy and redistribute the material in any medium or format) and adapt (remix, transform, and build upon the material for any purpose, even commercially, under the following terms: you must give appropriate credit to authors, provide a link to the license, and indicate if changes were made. you may do so in any reasonable manner, but not in any way that suggests the licensor endorses you or your use, you may not apply legal terms or technological measures that legally restrict othersfrom doing anything the license permits. copyright: the authors keep the rights to further publish their contents where they want 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(2001), ‘preferences for colours and colour emotion combinations in early childhood’, developmental science, 4(4), pp.389398. available at: https://doi.org/10.1111/1467-7687.00180 (accessed 18 january 2022). cultura e scienza del colore color culture and science 06 16 riv is ta s em es tr al e | h al fye ar ly jo ur na l | d o i: 10 .2 37 38 /c c sj .0 0 rivista dell’associazione italiana colore www.gruppodelcolore.it doi: 10.23738/ccsj.i62016.00 cultura e scienza del colore color culture and science http://www.gruppodelcolore.it 06numero 06 novembre 2016 number 06 november 2016cultura e scienza del colorecolor culture and science rivista semestrale dell’associazione italiana colore http://jcolore.gruppodelcolore.it/ issn 2384-9568 doi: 10.23738/ccsj.00 direttore responsabile | editor-in-chief maurizio rossi (politecnico di milano, it) redazione | associate editors aldo bottoli (b&b colordesign, it) daria casciani (politecnico di milano, it) davide gadia | deputy editor (università degli studi di milano, it) marco gaiani (università di bologna, it) veronica marchiafava (associazione italiana colore, it) silvia piardi (politecnico di milano, it) alessandro rizzi (università degli studi di milano, it) francesca valan (studio valan, it) editorial board members john barbur (city university london, uk) berit bergstrom (ncs colour ab, se) giulio bertagna (b&b colordesign, it) janet best (natific, uk) aldo bottoli (b&b colordesign, it) patrick callet (école centrale paris, fr) jean-luc capron (université catholique de louvain, be) daria casciani (politecnico di milano, it) osvaldo da pos (università degli studi di padova, it) bepi de mario (crasmi, it) hélène declermont-gallernade (chanel parfum beauté, fr) reiner eschbach (xerox, usa) alessandro farini (ino-cnr, it) christine fernandez-maloigne (university of poitiers, fr) renato figini (konica-minolta, eu) davide gadia (università degli studi di milano, it) marco gaiani (università di bologna, it) robert hirschler (serviço nacional de aprendizagem industrial, br) sandra krasovec (fashion institute of technology, usa) francisco imai (canon, usa) lia luzzatto (color and colors, it) kevin mansfield (ucl, uk) veronica marchiafava (associazione italiana colore, it) gabriel marcu (apple, usa) anna marotta (politecnico di torino, it) cultura e scienza del colore color culture and science rivista dell’associazione italiana colore registrazione presso il tribunale di milano al n. 233 del 24.06.2014 manuel melgosa (universidad de granada, es) anna grazia mignani (ifac-cnr, it) annie mollard-desfour (cnrs, fr) maria luisa musso (universidad de buenos aires, ra) claudio oleari (università degli studi di parma, it) galina paramei (liverpool hope university, uk) laurence pauliac (historienne de l’art et de l’architecture, paris, fr) silvia piardi (politecnico di milano, it) marcello picollo (ifac-cnr, it) renata pompas (afol milano-moda, it) boris pretzel (victoria & albert museum, uk) noel richard (university of poitiers, fr) katia ripamonti (cambridge research system, uk) alessandro rizzi (università degli studi di milano, it) maurizio rossi (politecnico di milano, it) jodi l. sandford (università di perugia, it) raimondo schettini (università degli studi di milano bicocca, it) gabriele simone (st microelectronics, it) andrea siniscalco (politecnico di milano, it) ferenc szabó (university of pannonia, hu) mari uusküla (tallinn university, ee) francesca valan (studio valan, it) ralf weber (technische universität dresden, de) alexander wilkie (charles university in prague, cz) peer review process tutti gli articoli inviati alla rivista “cultura e scienza del colore color culture and science” sono sottoposti ad un processo di revisione secondo la seguente procedura: prima revisione gli associate editors valutano ogni articolo per determinare se il tema e il contenuto sono di interesse per la rivista “cultura e scienza del colore color culture and science”. una volta valutati gli articoli, gli associate editors selezionano una serie di revisori scegliendoli scegliendoli nell’editorial board in base all’esperienza degli stessi in un particolare settore disciplinare o tema. seconda revisione ogni articolo è revisionato da due revisori in un processo in cui essi stessi e gli autori sono mantenuti anonimi. ai revisori è chiesto di valutare l’articolo considerando la sua originalità, la metodologia applicata e l’impatto sulla ricerca o sulla pratica professionale. dopo aver raccolto i commenti dei revisori, gli associate editors elaborano ed inviano al direttore responsabile un giudizio riassuntivo sull’accettazione o meno dell’articolo. collaboratori | contributors valeria biasi, letizia bollini, paolo bonaiuto, alessio cardaci, tiziana cavaleri, isabelle clonier, fabio colonnese, paola croveri, osvaldo da pos, annamaria giovagnoli, chiara gregoris, michela lecca, giulia pellegri, anna piccirillo, renata pompas, antonella versaci editore | publisher gruppo del colore – associazione italiana colore www.gruppodelcolore.it sede legale: piazza carlo caneva, 4 20154 milano (italia) all articles submitted to “cultura e scienza del colore color culture and science” journal are peer-reviewed according to the following procedure: first review the associate editors evaluates each article in order to define if the topic and content is suitable for consideration by the “cultura e scienza del colore color culture and science” journal. once the article passes the initial review, the associate editors select several referees in the editorial board based on their expertise in the particular field or topic second review each article is reviewed by two or three referees under a double-blind peer review process where the authors and the reviewers are kept anonymous. referees are asked to evaluate the manuscript based on its originality, methodology and impact to research and relevance to the professional practice. after collecting the referees’ reports, the associate editors makes a recommendation on the acceptability of the article to the editor in chief. doi: 10.23738/ccsj.i62016.00 gruppo del colore associazione italiana colore http://www.gruppodelcolore.it sommario | summary english | italian review 06 5 7 23 37 47 53 61 71 80 82 editorial by maurizio rossi chromatic gradation as a symbolic and spatial device in the european context: piero bottoni’s cromatismi architettonici la gradazione cromatica come dispositivo simbolico e volumetrico nel contesto europeo: i cromatismi architettonici di piero bottoni by fabio colonnese the restoration of color in the french historic cities: approaches, methods and experiences il restauro del colore delle città storiche francesi: approcci, metodi ed esperienze by antonella versaci, alessio cardaci colour and light in communication of fabric façades il colore e la luce nella comunicazione delle facciate tessili by chiara gregoris emotional qualities of colours added to humorous illustrations by valeria biasi and paolo bonaiuto topos vs. iris. colour design in web 3.0 mobile app and os: a critical review by letizia bollini chromatic and decorative planning choices: geometry, knowledge and survey by giulia pellegri colorimetric and spectrophotometric analyses for an ecoinnovative application of natural dyeing in textile conservation by tiziana cavaleri, isabelle clonier, paola croveri, annamaria giovagnoli, anna piccirillo food, colour and art by renata pompas communications and comments by michela lecca and osvaldo da pos coloumn english 4 cultura e scienza del colore color culture and science | 06 | 2016 issn 2384-9568 this page has been intentionally left white 5 cultura e scienza del colore color culture and science | 06 | 2016 issn 2384-9568 la rivista cultura e scienza del colore, edita dalla associazione italiana colore, è giunta al suo terzo anno di vita con la pubblicazione di questo numero sei. tre anni è un traguardo importante. già dallo scorso anno il comitato di redazione ha deciso di modificare progressivamente la modalità editoriale, che è presentata sul sito della rivista e nel colophon, con l’obiettivo di arrivare in futuro ad ottenere l’accreditamento scientifico a livello internazionale. questo processo avanza per passi successivi al fine di adeguarsi agli standard richiesti senza stravolgere la natura multidisciplinare della rivista e le motivazioni per cui è nata in seno alla associazione italiana colore. in una prima fase la rivista raccoglieva solo articoli, rieditati, di autori che partecipano alla conferenza del colore. però, negli ultimi tre numeri vi è stato un crescendo di altre ricerche proposte da autori stranieri. anche il livello di selezione degli articoli è migliorato grazie al lavoro attento che viene fatto in modalità doppio cieco dai membri del nostro board editorial internazionale. in questo numero abbiamo un chiaro esempio di integrazione multidisciplinare di temi inerenti il colore. fabio colonnese ci presenta un saggio su un caso studio molto interessante nel contesto del colore per l’ambiente costruito: gli studi del 1926 di piero bottoni sui cromatismi architettonici e una proposta di rielaborazione digitale per uno di questi studi. antonella versaci e alessio cardaci propongono una ricerca sui diversi metodi e le esperienze di restauro del colore nel contesto urbano francese tramite l’analisi di casi studio emblematici e significativi. il tema relativamente innovativo della comunicazione tramite l’utilizzo della luce e del colore sulle facciate degli edifici viene approfondito da chiara gregoris analizzando alcune delle possibili modalità ed evidenziando come, queste installazioni, stiano sempre più diventando punti di riferimento per il territorio. valeria biasi e marino bonaiuto presentano una ricerca nel contesto del colore e psicologia dedicata a dimostrare il fatto che il colore influenza la percezione emozionale delle vignette umoristiche. nel contesto del colore digitale viene presentata un’analisi di letizia bollini che pone chiaramente in evidenza una sorta di regresso progettuale nella liberalizzazione dell’uso del colore nelle interfacce del web3.0. giulia pellegri, organizzatrice della conferenza editorial the journal color culture and science, published by associazione italiana colore, is now in its third year of life with the publication of this number six. three years is an important milestone. since last year, the editorial board decided to gradually change the publishing mode, which is presented on the journal’s website and in the colophon, with the aim to arrive in the future to get a international scientific accreditation. this process advance by successive steps in order to comply with the standards required, without upsetting the multidisciplinary nature of the magazine and the reasons for which it was born within the associazione italiana colore. in a first phase the magazine collected only articles, reissued, by the authors participating in the italian conferenza del colore. however, in the last three numbers, there has been a crescendo of other researches proposed by foreign authors. also the level of selection of articles is improved thanks to the careful work that is done in doubleblind mode by members of our international editorial board. in this issue there is a clear example of multidisciplinary integration of topics related to color. fabio colonnese presents an essay on a very interesting case study in the color context for the built environment: the 1926 studies by piero bottoni on architectural colors and a proposal for a digital representation of one of these studies. antonella versaci and alessio cardaci propose a research about the different methods and color restoration experiences in the french urban context through the analysis of emblematic and significant case studies. the relatively innovative theme of communication through the use of light and color on the facades of buildings is deepened by chiara gregoris analyzing some of the possible ways and highlighting how, these installations, are increasingly becoming reference points for the territory. valeria biasi and marino bonaiuto present a research in the context of color and psychology dedicated to prove the fact that color affects the emotional perception of humorous illustration. in the context of digital color it is presented an analysis of letizia bollini that puts clearly in evidence some sort of regression design in the liberalization of the use of color in interfaces of web 3.0. giulia pellegri, organizer of conferenza del colore 2014, within themes of analytical drawing and representation, 6 cultura e scienza del colore color culture and science | 06 | 2016 issn 2384-9568 del colore 2014, nell’ambito delle tematiche analitiche del disegno e rappresentazione, propone un’attenta analisi della pianificazione delle attività di conservazione, manutenzione e restauro, delle facciate di edifici storici. infine tiziana cavaleri, isabelle clonier, paola croveri, annamaria giovagnoli e anna piccirillo presentano un’analisi colorimetrica di coloranti naturali nell’intervento conservativo su alcuni arazzi storici della reggia di venaria reale in piemonte. nella rubriche, renata pompas presenta le recensioni di due libri dedicati al tema del colore nel cibo e michela lecca con osvaldo da pos presentano una sintesi dei lavori del workshop “what is the color for me?” realizzato durante la conferenza del colore di genova per favorire lo scambio multidisciplinare di idee tra i membri della associazione italiana colore. editor in chief maurizio rossi proposes a detailed analysis of the planning of activities for the conservation, maintenance and restoration of historic buildings facades. finally tiziana cavaleri, isabelle clonier, paola croveri, annamaria giovagnoli and anna piccirillo have a colorimetric analysis of natural dyes in the conservation work on some historical tapestries of the royal palace of venaria in piedmont. in the columns, renata pompas presents the reviews of two books dedicated to the subject of color in food and michela lecca with osvaldo da pos present a summary of the proceedings of the workshop “what is the color for me?” made during the color conference of genoa to encourage the multidisciplinary exchange of ideas between members of the associazione italiana colore. editor in chief maurizio rossi 22 color culture and science journal vol. 14 (2) doi: 10.23738/ccsj.140203 pixar’s colorscripts: chromatic analyses of four films using sens|org|int model paula csillag 1 , amanda sabao 2 1 department of design, espm college and associação procor, são paulo, brazil. pcsillag@espm.br 2 department of design, espm college, são paulo, brazil. amandasabao@hotmail.com corresponding author: paula csillag (pcsillag@espm.br) abstract the objective of this study is to make chromatic analyses of the colorscripts of four pixar films using sens|org|int model. these analyses are intended to understand the use of color and their communicative intentions, as well as discuss communicative relationships between emotion and plot through the use of colors, identifying which aspects of chromatic perception are objective (physiological) and which aspects of chromatic perception are subjective or interpretive. the empirical research was conducted creating first an instrument of analyses for the colorscripts, based on the theoretical review. results of the analyses indicate not only that pixar uses color very coherently and effectively in terms of physiological visual perception, but also show which color uses and contrasts are mostly used and with which communication intentions. also, the analyses convey a broad scope of color associations in films that could be useful for future chromatic projects. keywords colorscripts, emotional associations to color, animation, cinema, color communication received 28/01/2022; revised 22/04/2022; accepted 31/07/2022 pixar’s colorscripts: chromatic analyses of four films using sens|org|int model 23 color culture and science journal vol. 14 (2) doi: 10.23738/ccsj.140203 1. introduction the concept of colorscript (figure 1) is a filming tool used in the production of some movies, mainly in animations. it allows us to see the full emotional mood that color brings to a film in a single glance, by arranging scenes side by side in a single plate. this process aims to plan and refine the visual and emotional rhythm of a film, so that it supports its story. (amidi, 2011) according to amidi (2011), the term colorscript was only recently adopted due to the great amplification, mainly by pixar, of its role in the film creation processes. there is some ambiguity about what constitutes a colorscript or at what stage in pre-production it should be done, there are several versions of the process, just as there are several artists to create them. in this research, the objective was to analyze the associations of colors and emotions present in animation colorscripts, mapping objective (physiological) and subjective (interpretative) factors used for these associations. fig. 1. colorscript of the film “finding nemo” source: the art of pixar (2011) 2. color in cinema to review the origin of color in cinema, the following authors were used: barbosa (2007); misek (2010); costa (2005); neale (1985); reis (2016); bordwell, staiger, thompson (1985); sagen (2015); braga (2000, 2011) and hercules (2012), referring to the painting methods used, companies that stood out and the importance of color in narratives. the methods used include the nonphotographic ones — hand painting, stencils, dyes, turnings and the handschiegl process — and the photographic ones — kinemacolor, kinekrom, gaumontchronochrome, cinecolorgraph, kodachrome, prizmacolor, lumicolor, dufaycolor, gasparcolor and technicolor. 2.1. colorscript this topic addresses the origin of the color-to-emotion mapping method used today by pixar's animated films. its origins date back more than seventy years, and its first versions began as soon as color made its presence felt in the cinematographic world. according to amidi (2011), in the mid-1930s, an initial colorscript process was created and employed in hollywood live-action films by natalie kalmus, supervisor of technicolor's color control department. soon, the concept of colorscript came to disney animated films in the 40s. the idea of presenting the colors of an entire animated film, in a single piece of art, as they are done today, didn't fully materialize until the films made by united productions of america, founded in the 1940s. inspired in disney's processes and with a team of artists who had already worked there, the upa created “continuous color sketches” for their films in the mid-40s. (amidi, 2011) the modern resurgence of colorscript was brought on by disney, more specifically, by artist richard vander wende who painted scenes from the entire aladdin movie. (amidi, 2011) according to amidi (2011), the term colorscript was only recently adopted due to the great amplification, mainly by pixar, of its role in the film creation processes. 3. sens|org|int model sens|org|int model (csillag, 2013; 2015) differentiates three processes that occur in human perception: sensory impressions, organizing processes, and interpretive processes of visual perception. the model was devised in an attempt to differentiate which principles of design tend to be common to all human beings with normal eyesight from the concepts that don’t. those that are not common therefore are learned or otherwise acquired. therefore, this model unites the synthetic approach (hering, 1964[1878]; gibson, 1979), and the analytical approaches (berkeley, 1709; helmholtz, 1925; bruce, green & georgeson, 2003), neuroscientific explanations (chalupa & werner, 2004; knoblauch & shevell, 2004; pinna & spillman, 2001; shimojo, kamitani & nishida, 2001; spillman & levine, 1971; zeki, 2000) on how the brain works, and relates them to design principles. with this framework, we are then able to tell, from the classical design “laws,” which ones can truly be considered a principle that tend to be valid for all human beings from those that don’t. pixar’s colorscripts: chromatic analyses of four films using sens|org|int model 24 color culture and science journal vol. 14 (2) doi: 10.23738/ccsj.140203 sens variable (sensory impressions) is related to the sensory information received through the pupil in our visual sensory organ. this aspect of perception is a phenomenon that occurs in the eye only, still in the form of light, before it becomes neural signs in the retina. org variable (organizing processes) is related to organizing aspects of perception that occur starting in the retina, including what is considered the primary visual cortex, mostly in area v1 of the striate cortex. org is related to the bottom-up approaches of visual perception in psychology. the phenomena of perception that occur as org are what tend to be considered as principles of design. int variable (interpretive processes) refers to the elaboration of org in the extrastriate visual cortex, including approximately areas v2, v3, v4 and v5 of the brain, and moving on to other areas of the brain. this variable refers to the top-down approaches to visual perception in psychology. it is in this moment of perception, that neural cascades occur, which undergo the interference of motivation, emotion, personality, culture, knowledge, etc. this aspect of perception causes variation and interpretation in design and in the proposed model, is called interpretive processes. figure 2 illustrates sens|org|int mode with the three variables. fig. 2. illutration of sens|org|int model 4. methodology and empirical research the empirical research consisted primarily on the analyses of colorscripts, based on sens|org|int model. thus, four pixar films were selected: finding nemo, up, cars and wall-e. these were specifically selected as they represent some of the studio's early films and feature a wide variety of color usage. following sens|org|int model, each colorscript was analyzed, in terms of objective percepts (org) and subjective percepts (int). due to space limitations, in this paper, only one example is illustrated below. an important scene of the film “finding nemo”, its colorscript indicates the moment when the character marlin finds the only survivor egg after a shark attack to his nest full of eggs. the colors used in the real film feature a very important characteristic, observed using sens|org|int model. in terms of org variable (objective percepts), it is noted that the contrast of the egg color and its surroundings is a contrast that indicates a more saturated and thus brighter orange for the egg. and marlin, when holding the egg on his fin, is featured with a desaturated orange (mixed with grey), indicating an orange with less brightness. fig. 3. colors used in the egg scene of “finding nemo”. figure 3 illustrates this use of color. marlin’s fin was featured in the film with a desaturated orange, the same color as the background of figure 3. the egg, which is the only survivor, and will become nemo, is featured in saturated orange, as the circle in figure 3. analyzing this scene in terms of int variable, it is noted that the usage of a desaturated orange for the father is associated with his stressful feeling at this moment, and the saturated orange used in the egg is associated with brightness, life and hope. the real image of the film is not featured here due to copyright permissions. so, in terms of org, the perception of brightness of the orange is used for the egg, featuring vibrancy. this use of color only could connote several emotions, but here sens||org|int model helps understanding the use of color, thus in terms of int, the symbolism the pure hue connotes joviality, hope, and llfe. the desaturated fin, in terms of org, is pixar’s colorscripts: chromatic analyses of four films using sens|org|int model 25 color culture and science journal vol. 14 (2) doi: 10.23738/ccsj.140203 perceived as less vibrant, and in terms of int, the symbolism of the desaturated fin relates to how the father is stressed and living a terrible moment. 5. results and final considerations through the analysis made in the colorscripts of some pixar films, it was possible to draw conclusions about their uses of color. first, in a general context, there is a very precise use of both objective and subjective factors in pixar cinematographic works. the studio knows and uses its knowledge in order to always add meaning to its productions from the initial stage (colorscript) to the film. in the analyses, in relation to objective factors (org variable), it was possible to observe a greater use of communication of spatiality through hot and cold or light and dark contrast. then comes the communication of smoothness through contrasting pastels and saturation. both stimulation and calm communication through hot and cold contrast and high vibration communication through complementarity contrast were equally used. next, there is the communication of vibration through contrast of pure hues, and finally there is the communication of chromatic mutation through simultaneous contrast. the greater occurrence of objective spatiality communication factors is due to the fact that the studio prioritizes, for the most part, highlights of the character or object in relation to its background or vice versa to attract the attention of the audience. in finding nemo, it is possible to observe a constant use of communication to highlight the fish in relation to the bottom. in the other films, however, there is a rotation, some scenes prioritize the characters while others, the setting. this power of choice between what should attract the most attention shows that pixar knows what it's doing and explores what best contributes to the understanding of its scene. there is also a higher occurrence of smoothness communication through saturation contrast than through pastel tones. this choice shows a preference of the studio to bring softness, but also to create focuses of attention, which occurs in the saturation contrast, since in places where pure hue was used, these focuses are created. in the analysis of the film wall-e, there was a choice to predominantly use the saturation contrast, while in the other productions the two cases happened saturation contrast and pastel tones -, again showing that the studio has the knowledge to recognize which case is ideal for each type of communication. in the communication of stimulation and calmness, it is possible to observe that in the films nemo and wall-e the intention of calmness is very present due to the existence of cooler tones in the analyzed scenes. in the films cars and up – altas aventuras there was a greater balance, in some cases there is a communication of calmness through the contrast between cool colors and in others communication of stimulation through the contrast between warm colors. this choice is mainly in line with the intention that the studio wants to convey at a certain point in the film. the communication of chromatic mutation occurred once, in cars, and is a little more complex as it requires the artist who creates the colorscripts to have knowledge of the change in the color of an image due to the color used in the neighboring image. this factor was very well explored in the film, with sunlight interfering with the color of the truck's shadow. high vibration communication through complementarity contrast occurs in all analyzed films, as well as vibration communication through pure hue contrast. vibration plays an important role in animations as it attracts the eye and generates vibration and dynamism, suitable for a child audience. as for the subjective factors, it is observed that, based on the authors analyzed, pixar knew how to use colors well in the context of communication, allowing interpretations that enrich its plots. subjective communication was widely used to confirm, mainly, the feelings of the characters in the scenes, which occurs in all the investigated films, in addition to also giving evidence of personality, which was again used in all productions. the subjective factors of colors were also used to accompany decision-making, as analyzed in the scenes of up – high adventures and cars, in moments when the colorscript color is aligned with a certain decision that determines the direction of the film. finally, subjective communication (int) is applied to reaffirm the role of a place or a character, as it happens in nemo, carros and wall-e, in moments such as when there is a feeling of danger with jellyfish (nemo movie), the trophy that must be overshadowed (movie cars) and the planet earth that must represent neglect (film wall-e). these and more examples show how subjective communication has been very well studied and constructed to allow a wide variety of emotions to enrich the film's plots. the analyses carried out on the objective (org) and subjective (int) factors only show how pixar masters the language of colors and methodically uses them to enhance its characters and stories with emotions, creating layers of interpretations and perceptions for its films. pixar’s colorscripts: chromatic analyses of four films using sens|org|int model 26 color culture and science journal vol. 14 (2) doi: 10.23738/ccsj.140203 in addition to mastering the objective factors, they also explore the subjective part of color well by contextualizing it in colorscript and film scenes in a way that enhances the communication of the story. it is hoped with this research that these studies and analyses can contribute to those interested in the area of film and animation production or even to other trainings such as design, serving as a guide for a conscious and expressive use of color. 6. conflict of interest declaration the authors declare that there is no conflict of interest regarding the publication of this paper. 7. funding source declaration this research was financially supported by espm college, by the iniciação científica program (pic). the financial support allowed full study dedication. 8. short biography of the author(s) paula csillag – professor doctor at espm college, since 1999, lecturing in the design department. research interests are related to color communication, visual language, color perception and color trends. amanda saibão – graduate in design at espm college. licensing terms articles published in the “cultura e scienza del colore color culture and science" journal are open access articles, distributed under the terms and conditions of the creative commons attribution license (cc by). you are free to share (copy and redistribute the material in any medium or format) and adapt (remix, transform, and build upon the material for any purpose, even commercially, under the following terms: you must give appropriate credit to authors, provide a link to the license, and indicate if changes were made. you may do so in any reasonable manner, but not in any way that suggests the licensor endorses you or your use, you may not apply legal terms or technological measures that legally restrict others from doing anything the license permits. the authors keep the rights to further publish their contents where they want and can archive pre-print and post-print (submitted version and accepted version) and the published version of the pdf of their article with no embargo period. references amidi, a. 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(2000). ‘the architecture of the colour centre in the human visual brain: new results and a review’. european journal of neuroscience 12 (1), 172-193. 33 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140104 prokudin-gorskii’s technique of colour photography: colour separation, additive projection and pigment printing nadezhda stanulevich1, 2 1 the laboratory of museum technologies, peter the great museum of anthropology and ethnography (the kunstkamera), saint petersburg, russia. nstanulevich@gmail.com 2 national research university 'higher school of economics', saint petersburg, russia. nstanulevich@hse.ru abstract russian scientist and photographer sergei prokudin-gorskii studied the additive method of colour photography at adolf miethe’s laboratory in berlin at the beginning of the twentieth century. in december 1902, prokudin-gorskii gave the first colour presentation at the photography section of the imperial russian technical society. prokudin-gorskii photographed the russian empire between 1905 and 1915. based on colour separation, he had successful optical colour projection and produced different types of colour prints. the library of congress purchased the main part of the negatives and reference print albums from his sons in 1948. details of his technique contain in patents, articles and reports. keywords colour photography, colour separation, additive projection, pigment printing, prokudin-gorskii, additive technology received 08/12/2021; revised 18/01/2022; accepted 28/01/2022 prokudin-gorskii’s technique of colour photography: colour separation, additive projection and pigment printing 34 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140104 1. introduction to record the word in colour was a mimetic dream shared by russian photographer sergei prokudin-gorskii (18631944). prokudin-gorskii’s technique for producing colour images was an additive colour screen process. he took more than 3500 colour photographs and most of the colour separate glass negative preserved by the library of congress during his activity. thanks to new digital technologies, prokudin-gorskii’s photographic legacy is becoming known worldwide. the photo historian sergei morozov (1955) was one of the first soviet researchers who mentioned the activities of prokudin-gorskii as a practical photographer. an important place in the study of the photographic heritage of prokudin-gorskii belongs to the works of the candidate of pedagogical sciences, professor svetlana garanina. in her first paper about the photographer (garanina, 1970), she told about the details of shooting the anniversary portrait of leo tolstoi in iasnaia poliana in may 1908 and prokudin-gorskii’s note about the technique of colour photography. professor garanina published about ten articles with biographic details and descriptions of prokudin-gorskii’s photographs. the authors of the first foreign publications about prokudin-gorskii (wall, 1925; friedman, 1945) gave characteristics of the contribution of scientists from different countries to the development of colour photography, indicating the patents, including the information about prokudin-gorskii. the albums with the colour images printed by prokudin-gorskii’s negatives from the library of congress collection describing the photographer’s biography and career are the primary publication type on a historical topic. one of the first english albums (allshouse, 1980) also presented the research on the history of the development of colour photographic processes and, in particular, the additive method (goldsmith, 1980). some new facts from scientific biography photographer and analysis of his practical publications were published by professor william brumfield's cooperation research and library of congress staff (brumfield, 1990). the library of congress annual newsletter describes the state of conservation of the collection, including glass negatives (robb, 2001). a recital of various publications and projects that appeared after the digitization of prokudin-gorskii's collection can be found in the article (leich, 2017). still, most researches focused on the sampler of russia’s past in colour, not on the details of the photographic process. this is mainly because most sources exist only in russian and have not been previously translated. in this paper, the photographic articles, different reports and patents are analysed from the point of view of the scientific biography of the photographer and technical details of the additive colour process and further uncovered the history of the photographic heritage of sergei prokudin-gorskii. 2. prokudin-gorskii science biography scientist, inventor, entrepreneur, and colour photographer sergei prokudin-gorskii was born into a noble russian family on 18 (30) august 1863 in vladimirskaia province (stanulevich, 2019). in october 1886, prokudin-gorskii enrolled as an irregular student at saint petersburg university. in the first semester, he listened to chemistry lectures by dimitri mendeleyev, inventor of the periodic table (prokudin-gorskii, 1886). mendeleyev influenced the young prokudin-gorskii’s interest in chemistry. also, prokudin-gorskii attended a class in analytical chemistry in autumn 1887, and the following autumn, he stopped his education at university (prokudin-gorskii, 1888). two months early, he started to be an irregular student at the imperial medical army college. in the fall semester of 1889, he also stopped his education at college (certificate, 1890). he did not complete the cycle of higher education, but the knowledge gained formed his main interests and skills: chemistry and photography. in 1890 prokudin-gorskii married anna lavrova, daughter of an industrialist alexander lavrov, an active member of the imperial russian technical society (irts). lavrov appointed his son-in-law director of the executive board of his steelworks, located in gatchina near saint petersburg. in 1896 prokudin-gorskii started to be a member of the chemistry section of the irts. two years later, he was a member of its photography section, presented an illustration report on photographing meteor showers. in the same year, he was one of the exhibitors at the 5th photographic exhibition at the irts with 23 gold and platinum-toned celloidin prints. for this exhibition, he used isochromatic and panchromatic plates by ilford and lumière to make photographs of oil paintings from a private collection of i. zabel’skogo (index for the 5th photographic exhibition organized by 5th department of irts, 1898). prokudin-gorskii maybe took his first photographs near summer 1892. he mentioned photographing in yalta in one of his first photo articles (prokudin-gorskii, 1897). this could be due to professional interest and an increased interest in photography in everyday life. in addition, the birth of children in the family of sergei prokudin-gorskii could serve as an appeal to photography the eldest son dmitry was born on 22nd january 1892 (korlyakov, 2009). since 1898, sergei prokudin-gorskii wrote reviews to international photographic news for the irts. i supposed prokudin-gorskii’s technique of colour photography: colour separation, additive projection and pigment printing 35 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140104 that he concentrated his attention on colour photography by these researches. on 30th october 1898, he had a report at the irts about new ives’ magic lantern for the projection from three colour-separated slides. prokudingorskii emphasized the merits of colour reproduction, indicated the considerable labour input in production and long exposure that embarrassed the photographing animate objects (prokudin-gorskii, 1899). he mentioned more than twenty years later in the british journal of photography pages (prokoudine gorsky, 1920): “certainly, such an arrangement, i.e., exact superposing on one and all of three pictures through three coloured screens is a slow process, but if it is done at once it series continually, and therefore the most advantageous condition for such projection is a permanent hall where the apparatus is fixed and will not be moved. with such an optical apparatus colour projection was shown for the first time by mr. f. e. ives. this apparatus was modified by myself, and from the point of view of rapidity of arrangements and quality it gave better results, and, having shown my pictures in different parts of russia by means of this apparatus. i had absolutely no competitors, not even autochrome, which made its appearance long ago, and which remains within close limits of private circles. more than a hundred projections shown by myself playing convinced me of the great interest of audience, regardless of their composition. it is only necessary that the show be accompanied by verbal explanation; no lecture is essential, but just a simple explanation of what it being shown.” on 29th january 1899, prokudin-gorskii demonstrated john joly’s colour photography of a parrot to irts’ members. interestingly, this type of bird was a favourite subject for photographing by all scientists who created colour photography. for example, alexandre-edmond becquerel (1820-1891) exhibited at the international exhibition in paris in 1855 one of his photographic plates depicting a parrot (pénichon, 2013). one of the leading figures in three-colour photographic processes louis ducos du hauron (1837-1920) demonstrated at the conservatoire national des arts et métiers in 1881 héliochrome depicting a parrot and a rooster, made in 1879 (lécuyer, 1945). the photographers’ choice for the shooting of the parrot was probably caused by the multicoloured plumage, which made it possible to demonstrate success in obtaining colour images and the reliability of colour reproduction of one or another photographic method. two months later, on 19th march 1899, sergei prokudingorskii showed at irts a stereoscopic photochromoscope by lumière (the photography section of the irts meeting journal on 19th march 1899, 1899). 3. colour separation, additive projection and pigment printing in the early 1900s, prokudin-gorskii opened in saint petersburg a photographic laboratory called “prokudingorskii’s art photomechanical studio”. at the first time, it produced photocopies from artworks, and then colour postcards and slides usually based on prokudin-gorskii’s separate negatives. also, studio specialised in making photolithography and microphotography. at the beginning of the twentieth century, he studied an additive method of colour photography intensely from adolf miethe in berlin. by analysing the dates, titles, and lists of participants of the irts’ meetings, we understand that prokudingorskii’s education in berlin ended in december 1902. as mentioned in some articles, documents about his travel to europe in the late 1880s (adamson, 2002, p. 108; allshouse, 1980, p. x) were not found during ten-year research. maybe, he had some travels to berlin in the late 1880s, but for the management of his father-in-law foundry, for the chemical and technical educational reasons. as adolf miethe, prokudin-gorskii created his photographs using a camera that exposed one oblong glass negative plate three times in rapid succession through three colour filters. prokudin-gorskii photographed with shutter by thornton-pickard and different objectives by steinheil or voigtländer (prokudingorskii, 1906c) because the usage of colour filters extended the exposition time and demanded high lens speed. in 1903 prokudin-gorskii published his results in booklet form, isochromatic photography with instant hand cameras and recommended using isochromatic plates by otto perutz’s factory-like a “perchromo” and “perorto platen” (prokudin-gorskii, 1903). the emulsion of these plates was made with the guidance of adolf miethe. as an analogue of perutz’s plates, prokudin-gorskii mentioned isochromatic products of different companies, for example, aktien gesellschaft fur anilin fabrikation, edward’s, lumière, and ilford. his first known lecture on three-colour photography was delivered on 13th december 1902, reported on colour slides by adolf miethe (adamson and zinkham, 2002). prokudin-gorskii ordered the projector in a german factory. later, this apparatus was destroyed after his leaving russia in 1918 (anon., 1932). a screen for projection was painted in white colour without blue pigment and then mounted to a black frame. a black dropdown curtain was lifted and closed for the projection of each image (the photography section of the irts meeting journal on 4th february 1905, 1905). prokudin-gorskii was one of the photographers who lectured about the regions prokudin-gorskii’s technique of colour photography: colour separation, additive projection and pigment printing 36 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140104 he travelled, using the colour slides he had produced. his son dmitry (1892-1963) often operated the lantern (anon, 1910). sergei prokudin-gorskii always had chosen a unique series of pictures that served the purpose of an action to viewers. it can be, for example, photographs of flowers (fig. 1), which have an excellent appeal for empress alexandra in may 1909. fig. 1. apricot flowers (dried apricots). samarkand. 19051915. sergei prokudin-gorskii. digital colour rendering from digital files from glass negatives. prokudin-gorskiĭ collection (library of congress). lc-dig-ppem-02155. at the first shows, prokudin-gorskii, probably, used a magic lantern with three lenses with attached colour filters that matched the red-green-blue separations on the glass slide. they formed a single, full-colour image when projected on a white screen in perfect registration. later he tried to create a system with one beam and multilayer transparencies. as he mentioned in the british journal of photography publication (prokoudine gorsky, 1920): the methods for the producing of transparency for the projection colour images existing at present can be divided into three groups: 1. autochrome and other similar methods [...] 2. different methods of gluing together films to films or to a glass […] 3. colouring of the diapositives, even if made sometimes with very transparent colours [...] after 1904 prokudin-gorskii began to develop a coloursensitive photographic plates. he had perfected a new method that gave equal sensitivity throughout the spectrum within a year. commenting on his colour images published in the journal fotograf-liubitel’, prokudin-gorskii mentioned that he processed a special emulsion that hypersensitised the ilford “red label” plates (prokudin-gorskii, 1906c). we found the same information (evdokimov, 1914) on paper about trichromatic prints by alexander evdokimov, prokudin-gorskii’s partner, between 1902 and 1914. prokudin-gorskii described drying the plates after sensitisation in his report at vi international congress of pure and applied chemistry in rome in 1906 (prokudingorskii, 1906a) and one of the articles on colour photography (prokudin-gorskii, 1906b). the patent for the process of sensitisation of the emulsion was not detected in different databases and archives. sergei prokudin-gorskii started to obtain patents in great britain, the usa, france and russia before the first world war for production of coloured slides, improvements in and relating to optical systems for the photographic camera, making multiple copies of colour slides etc. some of them are mentioned in books like history of three-color photography (wall, 1925) and history of colour photography (friedman, 1945). from the russian patent (patent #27542 was issued on 30th october 1914, 1914), we can derive that he started to use colour separate negatives exposed through red, green and blue filters for printing two autotype clichés (for magenta and yellow inks) instead of making a glass slide like a “sandwich”. through gelatin solution, magenta and yellow images were transferred from paper support to one glass plate. the third part was a cyan slide printed from a halftone negative that had been exposed through a red filter. the last step was mounting both-glass slides the magenta and yellow on one and the cyan slide on the other – together so that its result is one lantern slide. sergei prokudin-gorskii wrote that the slides looked like a pigment colour image in projection. the process of making clichés for colour printing described by alexander evdokimov in the first decade of the twentieth century contained the following steps: colour separation by the photographed through the three colour filters; contact printing of transparencies from each separated negatives; shooting from the scales; printing autotype negatives and then making clichés on copper or zinc (evdokimov, 1914). in 1905 and 1906, prokudin-gorskii mentioned that frankenstein-london company dyes were used in his studio in saint petersburg. for the best results, masters printed on paper four colours (yellow, red, blue and black) one after with a difference like 24 hours (fig. 2, 3). prokudingorskii started repeating the halftone process for each subtractive colour to make postcards with his colourseparated negatives since the same year. prokudin-gorskii’s technique of colour photography: colour separation, additive projection and pigment printing 37 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140104 fig. 2. yellow, red, blue and yellow plus red parts of colour prints. prokudin-gorskii, s. (1905) photomechanical work. saint petersburg: printing house “public benefit”. fig. 3. no title. postcard from oil painting. 1903-1905. photographer sergei prokudin-gorskii. nadezhda stanulevich private collection. the prokudin-gorskii’s studio was a typical printing enterprise before showing colour slides for emperor nicolas ii in may 1909. after the audience, the number of government orders increased. for example, prokudingorskii photographed the different objects for the government to publish historical albums for the centenary of the patriotic war 1812 and the three hundred anniversary of the house of romanov in 1913. he would also like to shoot the emperor’s ceremonial exits during the last celebration to colour cinematography. sergei prokudingorskii began to develop different technological stages of producing colour cinematography in 1910. continuing his scientific activity, sergei prokudin-gorskii participated in creating the higher institute of photography and photo technique in petrograd after the october revolution. realising the position of russian industry by the end of the first world war, he decided to do business abroad. in august 1918, he left petrograd for production colour cinema in norway. he moved to england in 1919 and then france in 1921. prokudin-gorskii, with his sons, dmitry and mikhail, founded a company, “societé de photochimie elka” named sergei prokudin-gorskii’s youngest daughter helena (later a company renamed to “gorsky frères”) in nice in 1924. prokudin-gorskii’s technique of colour photography: colour separation, additive projection and pigment printing 38 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140104 prokudin-gorskii’s photographs were demonstrated at the lectures russia in images in the different parisian organisations in the 1930s. all pictures were black and white because an additive magic lantern had been left in russia (stanulevich, 2020). since the second part of the 1920s, the photographer started to use film in his processes. prokudin-gorskii mentioned that fact in his notebooks. copy of these notes from the family collection in paris was presented by svetlana garanina, the first russian biographer of sergei prokudin-gorskii, to the polytechnic museum in moscow in 1995 (danilina, 1995). these documents show the history of prokudin-gorskii’s patent usage, describing his photographic processes’ modifications during the 1920s. on 18th december 1926, prokudin-gorskii had a report at the french photography society about making naturalcolour prints on paper. in the photographer's opinion, the photomechanical property of the elka paper was the possibility of the image being transferred to any desired surface. the image was transferred to a metallic surface and developed in hot water to remove all soluble gelatin at describing a process. the metallic silver of the films transformed into halide salt. finally, the plates are rinsed very briefly, merely to remove the excess of the solution, and each is immersed in a dye solution, orange-red, yellow and blue. when the three dyed images have thus been produced, all that remains is transferring one of the prints to the final support and superposing the other two upon it (colour photography on paper, 1926). in addition, notes contributed information about the contract between prokudin-gorskii and lumière’s label for the making film with prokudin-gorskii’s label – elka. despite the active popularisation of his photographic paper, prokudingorskii mentioned that he preferred to experiment with kodak transferotype paper for making slides since 1927 (prokudin-gorskii, no date, p. 16). kodak produced this paper to make enlarged negatives, glass positives or lanternslides, and prints upon opal glass, wood, metal tinted or other drawing paper, silk, satin, sateen, and other suitable support. in his notes, prokudin-gorskii explained the transition to kodak paper because elka paper, made at the lumière factory by 1927, was not the best quality. the disadvantages were uneven emulsion, dirt, excessive paper relief (prokudin-gorskii, no date, p. 12). before the 1950s, “gorsky frères” specialized in commercial printing for nestlé, fléchet, l’illustration and figaro. also, they partly realised an idea of creating a collection of french ethnographic types (one copy of prints was preserved by mikhail’s son serge procoudine gorsky (1932-2005) in paris). the colour prints with french views by “gorsky frères” are sometimes found on the delcampe website [1]. 4. heritage of sergei prokudin-gorskii the library of congress purchased prokudin-gorskii’s collection the photographer’s sons in 1948, after his death in 1944. the entire collection of glass negatives and albums with sepia-tone prints was digitised in 1999 and is available worldwide on the internet. in a 1995 interview, anna béraud (1930-1996), the granddaughter of prokudin-gorskii, said that the collection was kept in the basement (two or three square meters for each apartment) of a house at 69 rue de la tomb issoire, where the family lived since 1938. they were all afraid that the photographs would be spoiled without special preservation conditions (minachin, 2003). the library of congress collection includes 1902 black and white glass negatives and more than 3100 sepia-tone prints (fig. 4) without any colour or black and white slides. the size of the glass negatives is 9 x 24 cm. the dimensions of each image frame are 8.5 cm. wide and from 7.5 cm. to 8 cm. tall. prokudin-gorskii mentioned in his emigrant memoirs that he printed copies of images and collected them to the album after shooting. in this way, the albums from the library of congress collection were made. the author's numbering and titling were photographic prints from red filter glass negatives. although sometimes prokudin-gorskii wrote this information from memory and made mistakes, researchers determine now. the sepia-tone prints with size 8 x 8 cm. mounted on fourteen albums (usually six photos on each page of the album). not all materials of prokudin-gorskii are kept in the library of congress and other officially declared collections. it is known from archival documents that as of 1913, the photographer shot 3350 negatives and made 1000 slides (anon, 1913). in the case of the same subject, the library of congress collection may contain a set ‘negative and sepia-tone print’, or images are represented by only one type of material. and in the case of only having a sepiatone print, we can see the colour image only thanks to the finds of colour prints from various publications, for example, early twentieth-century books published in cooperation with prokudin-gorskii’s studio (fig. 4, 5). fifteen black and white slides of leo tolstoi’s estate in iasnaia poliana with the size of 8 x 8 cm are preserved at the institute of russian literature collection. twenty-four colour slides made in the 1930s on film are part of a private collection of prokudin-gorskii’s grandson, michelle soussaline. colour postcards, posters, illustrations for publications printed by prokudin-gorskii based on his separated negatives are part of the collections of archives and libraries in different countries. prokudin-gorskii’s technique of colour photography: colour separation, additive projection and pigment printing 39 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140104 fig. 4. vyborg castle. 1904. sergei prokudin-gorskii. photographic print. prokudin-gorskiĭ collection (library of congress). lot 10333, no. 91. fig. 5. vyborg castle. example of colour printing. prokudin-gorskii, s. (1905) photomechanucal work. saint petersburg: printing house “public benefit”. prokudin-gorskii’s technique of colour photography: colour separation, additive projection and pigment printing 40 color culture and science journal vol. 14 (1) doi: 10.23738/ccsj.140104 5. conclusion sergei prokudin-gorskii was a talented inventor who used his scientific background. the main interest of the additive process is that a black and white image is used directly as the base of the colour image. prokudin-gorskii wrote in emigration (prokoudine gorsky, 1920) that having been occupied with the problem of colour cinematograph since 1912; he concluded that the principle of three separate negatives was the most advantageous because it allowed large amplitude in the ratio of exposures. moreover, in his opinion, these negatives can be utilised for another very useful purpose: optical colour projection and producing colour prints typographically. in my opinion, the main contribution of prokudin-gorskii to the development of the additive method is the refinement of the emulsion for the plates, development of technology for creating colour slides with a transition to attempts to develop colour cinematography. also, he selected shooting parameters for various weather conditions on the territory of the russian empire, created a series of surveys that included at least 3500 negatives, arranged the use of colour-separated negatives for printing colour illustrations and trained masters in his studio. 6. conflict of interest declaration the author declares that nothing affected their objectivity or independence and original work. therefore, no conflict of interest exists. 7. funding source declaration this research did not receive any specific grant from funding agencies in the public, commercial, or not-forprofit sectors. 8. short biography of the author nadezhda stanulevich is a photo historian. she defended her candidate of science dissertation entitled sergei prokudin-gorskii and his contribution to the development of colour photography in 2019. most of her peer-reviewed articles focus on the history of photographic techniques or museums collections. since september 2019, she has been a researcher at peter the great museum of anthropology and ethnography (the kunstkamera). notes [1] https://www.delcampe.net/en_us/collectibles/engravings/lot-de-3tableaux-province-de-france-sous-verre-45-x-54-cm-photos-gorsky1947-1948-voir-7-photos-159030833.html references adamson, j. and zinkham, h. 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(1925) the history of three-color photography. boston: american photographic publish company. 19 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110102 color emotion as a feasible tool in a participatory project for a primary school cristina boeri 1 1 color lab, department of design, politecnico di milano, cristina.boeri@polimi.it corresponding author: cristina boeri (cristina.boeri@polimi.it) abstract the experimentation conducted during a participatory pilot research project in a primary school in milan, explored the use of emotional associations of color through the identification of evocative terms, or “emotion words”, together with color combinations and images of projects in specific contexts, as a basis for comparison, discussion and verification, and, to conclude, for development of project hypotheses. even if we cannot, on a numerical level, consider significant the reference sample used within the participatory process, both in the preliminary and in the verification phase of the methodological assumptions, the results of the experimentation led us to assume that the design methodology we identified and adopted proved to be functional in order to facilitate comparison and verification within the participatory process and subsequently develop design hypotheses based on the same comparison and verification. keywords color emotion, color design, color preference, color in educational environments received 16 may 2019; revised 04 june 2019; accepted 20 june 2019 citation: boeri, c. (2019). color emotion as a feasible tool in a participatory project for a primary school. color culture and science journal, 11(1), 19–27. https://doi.org/10.23738/ccsj.110102 color emotion as a feasible tool in a participatory project for a primary school 20 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110102 1. introduction the evaluation of the emotional response to color, or “color emotion”, has been the focus of a great number of researches, and can be divided into two broad categories, as noted by gao and xin (2006): one related to the aesthetic experimentation of color, or color preference, which addresses the color evaluative dimensions, and the other related to the color descriptive dimensions, linked to connotations like warm or cool, light or dark, heavy or light, etc. a few of these studies evaluated emotional color preferences and associations in children (boyatzis and varghese 1994; burkitt et al. 2003; pope et al. 2012). these studies suggested that the positive or negative emotions associated to color depended on the individual child’s personal experience (boyatzis and varghese 1994). children tended to associate their favorite colors with the positive characters of a drawing and the least preferred to the negative characters of a drawing (burkitt et al. 2003) and also to associate their preferred colors with positive feelings (pope et al. 2012). in particular, the study of boyatzis and varghese (1994) investigated the color preferences in children aged 4-5 and 6-7 years, compared to nine different colors and the emotional reactions they had to each of these colors, expressed verbally. the study showed that the emotional associations elicited in the children by the selected colors were mostly positive. the percentage of positive emotional responses was higher for the bright colors (pink, red, yellow, green, purple, and blue) than for the dark colors (black, brown, and gray). the positive emotions mentioned by the children were codified as happiness, strength, and excitement and the negative ones as sadness, anger, and boredom (boyatzis and varghese 1994, p. 80). some of these studies focused on children preferences in pre-school indoor environments using, for this purpose, the image of a digitally manipulated school space to create different color alternatives (read and upington 2009; dalirnaghadeh 2016). in the study by read and upington (2009) the colors of the photographic image of an interior corner of a child development center were modified using the following colors: purple, blue, green, yellow, orange, red, and gray, of which, however, the various manipulation results were not provided, nor a more precise coding on the adopted lightness and saturation levels. the study showed that the red image was the most selected as a first choice, followed by the purple one, which was the favorite of the girls. the gray image was mostly selected as the last choice. in the study by dalirnaghadeh (2016), only the walls of the photographic image of the environment were modified using a high and low saturated red, a high and low saturated blue, and a high and low saturated gray (but since they were achromatic grays it would be more correct to say a light and a dark gray), and a white. the study showed that the high saturated blue was the most preferred and was associated with the positive emotion of happyness and the high saturated red the least preferred and associated with the negative emotions of anger (dalirnaghadeh 2016, p. 80). as for the achromatic schemes, the results suggested that the most preferred classroom was the one with the white, which was associated with happiness, while the one with the high saturated gray was the least preferred, and associated with anger (dalirnaghadeh 2016, p. 82). among the aims of these studies, we may also see the opportunity for discussion, with respect to the value of the context in which the preferences of color are expressed, and hence on the possible design implications related to this research area. in the study by park (2014), the correlations between color attributes and color preferences in children were analyzed using scale models of rooms. as stated by the same park, compared to the numerous studies on color preferences that made use of small color samples, his study focused on the environmental effects of color through physical simulation models in order to investigate the color preferences in a real context. as noted by küller (1981), with regard to the studies conducted on color preferences, one of the most critical issues is linked to the fact that most of these studies are without contextualization, and the other to the fact that most of these studies focus on preference or meaning of single colors rather than color combinations. this is the background to the experimentation we conducted during a participatory pilot project in a primary school in milan, which explored the possibility of using emotional color associations, through the identification of connotative terms or “emotion words” to be associated with color schemes, and images of projects in specific contexts, as a basis for comparison, discussion and verification, and, as a final point, to develop of design hypotheses. 2. the pilot project “let’s design the school together” the pilot project “let’s design the school together”, concerning the participatory planning of the school environments of a primary school belonging to the color emotion as a feasible tool in a participatory project for a primary school 21 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110102 “istituto comprensivo luigi cadorna” in milan, had as a main goal the identification of innovative criteria for the design and redevelopment of schools. the two-year long project was completed in 2018. the salient points of the design method adopted focused on a participatory planning with children, teachers and parents and a design by a multidisciplinary team of architects, designers and engineers [1]. the participatory project was carried out through design workshops with children and questionnaires addressed to children and adults [2]. the analysis of the state of the art and the results of the participatory methods produced a number of “design responses”, regarding both the architectural works and the space refitting, and the qualitative interventions related to furnishing solutions, materials, light and color. the latter were developed for each individual area of expertise, and in working groups interspersed with moments of comparison and sharing [3]. each work group was provided with a summary of the outcomes of the design workshops made with children and the project questionnaires, as a basis to create the design concepts that would later be submitted to the school community and, following discussion and verification, become project proposals. briefly, the school was built in 1932, and houses today a primary school and a preschool, which are part of the “istituto comprensivo luigi cadorna”, plus a municipal micro-nursery. about 500 pupils attend the school, including primary and preschool. the building consists of three floors above ground and a basement. the access is from a raised ground floor where the office block and the meeting rooms, the kindergarten, the micro-nursery and one of the two gyms are located. on the first floor there are the classrooms of the primary school, the second gym, the laboratories and the library. on the second floor are the remaining classrooms of the primary, other laboratories, the literacy classrooms, a large multipurpose hall and the school of italian for mothers. in the basement there are the refectory and the technical and storage rooms, a small gym and a multifunctional space used for exhibitions, workshops, meetings, gatherings, parties, etc. the school is also equipped with outdoor spaces. 3. the color project and the design methodology adopted in the participatory process the operative methodology explored within the participatory pilot project for the cadorna primary school was based on the need, on the one hand, to translate the desires expressed or that could possibly be expressed during the participatory process and, on the other, to build a basis for comparison, discussion and verification on which to develop the design hypotheses. within the various questionnaires given to each work group in the form of a summary of the results, specific questions on color were provided. in particular, in the questionnaire relating to “my class” the children in a third grade class of an average age of 8 years, were asked to answer the question “do you like colors?” and all the fourteen answers were positive. another of the questions asked the children “what color would you like in your class?” and of the fourteen answers given, most expressed a preference for two colors (10), followed by a preference for single colors (3) and then for four colors (1). the overall results showed how the most mentioned color was light blue (table 1). 6 5 5 4 3 2 1 1 light blue yellow white red green blue purple black table 1 – the color named by the children sample in answer to the question “what color would you like in your class?”. (multiple color choices are reported). other specific questions about color were addressed to the children of the same class, within the section of the questionnaire “how is your school when you enter the building?” one of the questions asked, “what color would you like to have in the corridors and throughout your school?” from the fifteen answers given, we observed that most children responded with a polychromatic meaning by repeatedly using the term “rainbow” (6) in addition to one answer that read “all” (1). the overall results showed that most children responded “rainbow” (6), followed by red (2 red, 1 dark red, 1 fiery red), sea green (1), blue and purple (1) (table 2). 6 4 1 1 1 1 2 rainbow red purple blue sea green all colors other table 2 – the color named by the children sample in answer to the question “what color would you like to have in the corridors and throughout your school?”. (multiple color choices are reported). within the section “what would i like to do at school?” there were other specific questions about color directed to the association between colors and particular activities such as studying, resting and playing (table 3). therefore, the analysis of the questionnaire summaries offered us the possibility of assessing the children’s color emotion as a feasible tool in a participatory project for a primary school 22 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110102 responses not only in terms of preferences accorded to a single color, but also in presence of recurring multiple choices of colors as well as of choices of multiple color combinations. to study (16 responses) 8 7 3 2 3 rainbow | all colors | multicolor red light blue green other to relax (17 responses) 8 4 3 2 2 light blue green blue yellow other to play (17 responses) 6 6 4 3 2 green red blue light blue other table 3 – the color named by the children sample in answer to the questions “what color would you like to have in your school to study?”, “the color to relax?”, “the color to play?”. (multiple color choices are reported). this datum, together with the partiality of the rather small sample offered by the results of the questionnaires, inspired us to identify and explore a methodology that would allow us to base the design hypotheses not so much on the individual and specific color preferences detected and detectable but on the possibility of translating and summarizing the desires and suggestions expressed, specifically by children, through keywords associated to multiple color combinations. 3.1. method and materials the method we identified, consists (a) in the possibility to analyze and synthesize the recurring descriptions and suggestions given by the children in the questionnaires to express how they would like their school spaces to be in evocative terms or “emotion words”; (b) to associate the identified “emotion words” with 4-colors palette examples, suggesting possible application scenarios through the use of illustrative and contextualised images; and, finally, (c) to subject them to verification and discussion. the analyses of the descriptions and suggestions most used by children in the questionnaires to express how they would like their school spaces were summarized in the “emotion words” soft, natural, warm and rainbow (fig. 1). the first two referred to “the school i want” and hence they summarized the wishes expressed by the children about how they would like the spaces of their school to be. instead, the word “warm” referred to “the school as it is” and thus summarized a positive connotation used to describe how the school was perceived. finally the term “rainbow”, in the double meaning of polychromatic and transformable, referred directly to the color preferences expressed by the children and to a recurring description they used to describe how they would like their school spaces to be. each of these “emotion words” was associated with an exemplifying 4-colors palette, and a specification of the hue, lightness and saturation attributes that eventually characterized the palette, using the visual representation of the ncs, natural colour system, color circle and color triangle. the palette was developed using as a reference source the literature and experimental research that addresses the synesthetic and emotional associations of color (kobayashi 1991; mahnke 1996; tornquist 1999; riccò 2005, 2008; da pos 2007; boeri 2019). for each “emotion word”, we suggested some possible combinations with materials, shapes and finishes (fig. 2) and, in a additional table, we associated illustrative images, related to school environments, and selected for their affinities with the color palettes and the sensory characteristics described (fig. 3). figure 1 – the “emotion words” that were identified to summarize the recurring descriptions and suggestions used by the children to describe the school spaces and how they would like them to be. the illustrative tables prepared in this way were object of comparison, discussion and verification during a round table with students, teachers and parents and open to the territory [4]. in this phase of discussion and verification, new questionnaires were also prepared, and each work group was given the opportunity to formulate specific questions consistent with the different design approaches and methods adopted. in the case of color, the questions formulated were directed to verify the methodological assumptions and the design objectives and, therefore, color emotion as a feasible tool in a participatory project for a primary school 23 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110102 above all the selected “emotion words” and the proposed associations with the color [5]. soft children (5 responses) 2 1 1 1 white red blue light blue soft adults (10 responses) 4 3 1 1 1 light blue pink white blue yellow natural children (5 responses) 3 2 green light blue natural adults (10 responses) 7 1 1 1 1 green light blue blue beige brow n warm children (5 responses) 3 2 yellow red warm adults (10 responses) 5 4 4 yellow red orange table 4 – the color named by the children and adults sample in answer to the questions related to the color associations with the selected keywords. (multiple color choices are reported). in particular, the participants were asked what color they associated with the “emotion words” soft, warm and natural. the questionnaire was completed by 5 children (belonging to the same third grade class who had participated in the previous questionnaires), and 10 adults (mainly parents of children attending the school). from the answers to the questionnaires filled in by the children, we could observe a congruence between the colors associated with the warm and natural “emotion words” and the suggested palette – for the warm, the most mentioned colors were respectively yellow and red and for the natural, green and light blue – while the association of color with the soft appeared to be more heterogeneous and there was no congruence with the suggested palette (table 4). from the answers of the questionnaires completed by the adults, we observed an analogous congruence between the colors associated with the warm and natural “emotion words” and the suggested palette – for the warm, the most mentioned colors were yellow, red and orange, and for the natural, green – and a certain congruence with the suggested palette for the soft, as regards the parameter of lightness and saturation (table 4). although the number of participants in this questionnaire should be considered rather small, we decided to proceed with the formulation of the design hypotheses, consolidating the identified “emotion words”, and possibly rereading the related chromatic-sensorial scenarios, seen as flexible matrices on which we could develop the emotional identity of the environments and then combine this identity with other design implications related to the functionality of color in school environments. 3.2. design hypotheses the proposed design hypotheses dealt with logic of recognition of the different functional distributions in which the school plans are organized, and of the different sections in which the school plan is divided. each section was characterized by the presence of a dominant color that made it recognizable among the others. that dominant, for the two floors housing the primary school classrooms, was identified in the conjugation of the two “emotion words” warm and rainbow, defining the following 4 colors to differentiate the four sections: yellow, orange, red, purple, while the basement was identified also by the “emotion word” natural, in addition to the previous warm and rainbow, defining thus 4 other colors to differentiate the existing 4 sections: yellow, yellowgreen, green-yellow, green (figs. 4-5). within this logic, the design and illustrative hypotheses relating to the specific areas of the school were formulated. for example, within the standard classroom and relative relaxation area, it was foreseen that each dominant could be flexibly used according to different, potentially even alternative, distribution forms (fig. 6). the color palette developed for the classroom was based on the “emotion word” warm, while for the relaxation area there was a different color palette based on the two “emotion words” natural and soft, offering a different color saturation and lightness on the yellow-green and blue-green shades. color emotion as a feasible tool in a participatory project for a primary school 24 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110102 figures 2-3 – an example of the tables showing, for each “emotion word”, the associations with exemplifying 4-colors palettes, the possible associations with materials, shapes and finishes and image examples related to school environments. color emotion as a feasible tool in a participatory project for a primary school 25 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110102 figures 4-5 – the color concept developed for the cadorna primary school. color emotion as a feasible tool in a participatory project for a primary school 26 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110102 figure 6 – the design hypotheses for the standard classroom and the relative relaxation area. 4. results and discussion the experimentation conducted during the participatory pilot project for the cadorna primary school explored possible design applications in the area of research called “color emotion”, having as a main goal the possible implementation of polychromatic settings in school environments based on color preferences and emotional responses. to this purpose, the “emotion words” we selected to summarize the most recurrent descriptions and suggestions used by the children involved to describe how they would like their school environments to be, turned out to be an optimal tool to build associations of color combinations, related to possible chromaticsensory scenarios and illustrative images of real environments, as a basis for comparison, discussion and verification, and, therefore, for the development of design hypotheses. even if we cannot, on a numerical level, consider significant the reference sample used within the participatory process – both in the preliminary and in the verification phase of the methodological assumptions –, the results of the experimentation led us to assume that the methodology we identified and adopted proved to be functional in order to facilitate comparison and verification within the participatory process and subsequently develop design hypotheses based on the same comparison and verification. the design implications raised by the experimentation contributed to frame color preferences and emotional responses to color in terms of combinations of multiple colors, and also highlighted the need, for the purposes of the possible design applications in this area of research, for greater contextualization, as küller (1981) observed, also in reference to the preference accorded to the use of color combinations. a second aspect raised by the experimentation was related to the possibility of using color preferences in order to promote a greater, and desirable, participation by children, in the design and configuration of school environments (read and upington 2009; gaines and curry 2011). in this experimentation, the role of color within the participatory process was understood on the basis of the attribution and association possibilities that can be established between the “emotion words” and the color-sensory scenarios. thus attributing the function of conveying the visual, sensory and meaningful qualities upon which to build the emotional identity of school environments to color. color emotion as a feasible tool in a participatory project for a primary school 27 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110102 5. conflict of interest declaration the author declares no conflict of interest related to this publication. 6. funding source declaration this research did not receive any specific grant from funding agencies in the public, commercial, or not-forprofit sector. 7. short biography of the author(s) cristina boeri architect phd, her activity in the research, teaching and professional sectors, deals with aspects related to the color perception and design. since 2001, she carries out educational and research activities in the color lab of the department of design of the politecnico di milano. she is adjunct professor of color and perception at the school of design, politecnico di milano. notes [1] project team: arch. cristina boeri, arch. paola branduini, dr. daria casciani, landscape architect gwenaëlle charrier, dr. chiara iemmolo, arch. francesca lanz, eng. maria gabriella mulas, arch. ilaria oberti, landscape architect rosi sgaravatti, arch. linda poletti project leader. [2] the design workshops and questionnaires have been designed and edited by linda poletti. [3] working group for color: cristina boeri with the collaboration of chiara iemmolo. [4] round table “let’s design the school together”, december 5, 2017, aula delle culture, scuola cadorna, milan. [5] the development, collection and synthesis of the questionnaires was edited by linda poletti. references boeri, c. (2019) ‘an educational experience on the exploration and experimentation of colour associations and relationships’, journal of the international colour association, vol. 24, pp. 1-10. boyatzis, c. j. and varghese, r. (1994) ‘children’s emotional associations with colors’, the journal of genetic psychology, 155(1), pp. 77-85. burkitt, e., barrett, m. and davis, a. (2003) ‘children’s colour choices for completing drawings of affectively characterised topics’, journal of child psychology and psychiatry, 44(3), pp. 445–455. dalirnaghadeh, d. (2016) the effect of chromatic and achromatic color schemes on children’s emotions in a preschool classroom, master’s thesis, department of interior architecture and environmental design, i̇hsan doğramacı bilkent university, ankara. da pos, o. and valenti, v. (2007) ‘warm and cold colours’ in guanrong, y., haisong, x. (eds.), aic2007 color science for industry, proceedings of the aic 2007 midterm meeting, color association of china, hangzhou, pp. 41-44. gaines, k. s. and curry, z.d. (2011) ‘the inclusive classroom: the effects of color on learning and behavior’, journal of family & consumer sciences education, 29(1), pp. 46-57, available at: http://www.natefacs.org/jfcse/v29no1/v29no1gaines.pdf (accessed: 25 february 2019). gao, x-p. and xin, j. h. (2006) ‘investigation of human’s emotional responses on colors’, color research and application, 3(5), pp. 411417. kobayashi, s. (1991) color image scale. kodansha. küller r. 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(2005) ‘sinestesie del colore: fra ricerca e sperimentazione didattica per il design di comunicazione’, in prima conferenza nazionale del gruppo del colore, andrea raggi (ed.), colore e colorimetria: contributi multidisciplinari, pescara, 20-21 ottobre 2005, firenze: centro editoriale toscano, pp. 315-322. tornquist, j. (1999) colore e luce. teoria e pratica. milano: istituto del colore. color culture and science cultura e scienza del colore ccsj volume 14 number 1 2022 issn 2384-9568 color culture and science journal cultura e scienza del colore ccsj jcolore.gruppodelcolore.it issn 2384-9568 doi: 10.23738/ccsj.00 ance: e227716 registrazione tribunale di milano n. 233: 24/06/2014 anvur agenzia nazionale valutazione sistema universitario e ricerca apej academic publications ejournal base bielefeld academic search engine dbh database for statistikk om høyere utdanning doaj directory of open access journals ezb elektronische zeitschriftenbibliothek regensburg jurn search tool for open access content road directory of open access scholarly resources volume 14, number 1, april 2022 doi 10.23738/ccsj.140100 publisher gruppo del colore – associazione italiana colore www.gruppodelcolore.org registered office: piazza carlo caneva, 4 20154 milan (it) peer review process all articles submitted to the color culture and science journal are peer-reviewed according to the following procedure: first review level the associate editors evaluate each article to determine if the topic and content are of interest to the journal. once the article passes the initial review, the associate editors select several reviewers from the editorial board based on their expertise in a particular subject area or topic. second review level two or three experts review each article with a blind peer-review process where the reviewers are kept anonymous. reviewers are asked to evaluate the manuscript based on the following criteria: − originality − relevance to journal's aims and scope − technical merit and/or validity − soundness of methodology − completeness of the reported work − conclusions supported by the data − correct acknowledgment of the work of others through reference − effectiveness of the manuscript (organization and writing) − clarity of tables, graphs, and illustrations − importance to color researchers − relevance to color practices if the article is accepted with major revisions, the author(s) are asked to improve the article according to the reviewers' suggestions. the revised article will then be submitted for further review. after collecting the reviewers' reports, the associate editors recommend the acceptability of the article to the editor-in-chief. editor-in-chief maurizio rossi (politecnico di milano, it) deputy editor alice plutino (università degli studi di milano, it) associate editors josé luis caivano (universidad de buenos aires, ar) vien cheung (university of leeds, uk) marco gaiani (alma mater studiorum università di bologna, it) robert hirschler (serviço nacional de aprendizagem industrial, br) agata kwiatkowska-lubańska (academy of fine arts, kraków, pl) marcello picollo (ifac-cnr, it) verena m. schindler (chair aic s.g. environmental colour design, ch) renzo shamey (nc state university, usa) editorial board members the complete and updated list of the editorial board members involved in the peer review process is available on the ccsj website: http://jcolore.gruppodelcolore.it/ojs/index.php/ccsj/about/editorialteam topics the ccsj accept papers on a wide range of topics on color, including and not limited to the following: 1. color and measurement/instrumentation. colorimetry, photometry and color atlas: method, theory and instrumentation; quality control and food coloring, dyes, organic and sustainable color. 2. color and digital. reproduction, management, digital color correction, image processing, graphics, photography, film and video production, printmaking and 3d print, artificial vision, virtual reality, multispectral imaging, data visualization. light field imaging. multi-sensor fusion. color localization, recognition, hdr imaging, adas systems. 3. color and lighting. metamerism, color rendering, adaptation, color constancy, appearance, illusions, color memory and perception, color in extra-atmospheric environments, lighting design, lighting technologies, visual comfort. 4. color and physiology. mechanisms of vision in their experimental and theoretical aspects, color vision and color appearance, deficiencies, abnormalities, clinical and biological aspects, synesthesia, health, well-being. 5. color and psychology. phenomenology of colors, color harmonies, color & form, perceptive, emotional, aesthetic, and diagnostic aspects. 6. color and production. food and beverages, agriculture, textiles, plastic materials, ceramics, paints, gemology, color in the food industry. 7. color and restoration. archaeometry, painting materials, diagnostics, and conservation techniques, restoration, and enhancement of cultural heritage. 8. color and environment. representation and drawing, urban planning, the project of color, architecture, interior design, landscapes & horticulture, color and architectural syntax, territorial identities, biodiversity. 9. color and design. furniture, cmf design, fashion, textiles, textures, cosmetics, food design, museography. 10. color and culture. arts and crafts, history, philosophy, aesthetics, ethno-anthropology, graffiti, geology, sociology, lexicology, semantics, anthropology of vision, food culture and heritage, color naming. 11. color and education. pedagogy, didactics of color, aesthetic education, artistic education. 12. color and communication/marketing. graphics, communication, packaging, lettering, exposure, advertising. http://jcolore.gruppodelcolore.it/ojs/index.php/ccsj/about/editorialteam 3 color culture and science journal vol. 14 (1) issn 2384-9568 table of contents editorial 5 barbara cattaneo, marcello picollo the flexichrome: visual examination and scientific analysis of an overlooked color process. 7 nayla maaruf, sylvie pénichon, maria kokkori doi: 10.23738/ccsj.140101 the jos-pe process in the jacob merkelbach collection at the rijksmuseum in amsterdam 16 laura covarsí doi: 10.23738/ccsj.140102 the long-term development of three-color kodachrome. an odyssey from the additive to the subtractive method of color reproduction 24 nicolas le guern doi: 10.23738/ccsj.140103 prokudin-gorskii’s technique of colour photography: colour separation, additive projection and pigment printing 33 nadezhda stanulevich doi: 10.23738/ccsj.140104 two prizma color films, a curious finding in the mexican national film archive 42 paolo tosini doi: 10.23738/ccsj.140105 the start of the rainbow: possibilities of color motion photography for the amateur 47 louisa trott doi: 10.23738/ccsj.140106 digital struggles for film restoration: la battaglia dall’astico al piave 55 serena bellotti, simone venturini doi: 10.23738/ccsj.140107 4 color culture and science journal vol. 14 (1) issn 2384-9568 modern methods for the visualization of lenticular film colors 64 david pfluger, lutz garmsen, giorgio trumpy doi: 10.23738/ccsj.140108 fine arts on film: the hand-painted work of stan brakhage 73 sabrina negri doi: 10.23738/ccsj.140109 the relationship between photo retouching and color grading 79 ivan magrin-chagnolleau doi: 10.23738/ccsj.140110 what about discoloration in plastic artifacts? the use of fiber optic reflectance spectroscopy in the scope of conservation 87 eva mariasole angelin, costanza cucci, marcello picollo doi: 10.23738/ccsj.140111 is a house named “yellow” really yellow? survey on the perception and naming of the yellow color on building facades depending on its hue, lightness and saturation 94 justyna tarajko-kowalska doi: 10.23738/ccsj.140112 scientific basics in art from the theories of colour: authors, methods, rules, applications 101 anna marotta doi: 10.23738/ccsj.140113 about the influence of color perceived lightness on psychological functions 112 alessandro bortolotti, loreta cannito, stefano anzani, maurizio rossi, riccardo palumbo doi: 10.23738/ccsj.140114 colour measurement and documentation in historical buildings: the case study of the kirna manor house in estonia 123 claudia valge, sofia ceccarelli, silvia bertacchi, andres uueni, hilkka hiiop, anneli randla, fabrizio ivan apollonio doi: 10.23738/ccsj.140115 book review: light the color of desire 131 renata pompas 5 color culture and science journal vol. 14 (1) issn 2384-9568 editorial the gruppo del colore – associazione italiana del colore (color group – italian color association, https://gruppodelcolore.org/?lang=en), in collaboration with the istituto di fisica applicata “nello carrara” of the consiglio nazionale delle ricerche (ifac-cnr) and the opificio delle pietre dure (opd), organized the first edition of the international conference on “colour photography and film: sharing knowledge of analysis, preservation, conservation, migration of analogue and digital materials” on 29th and 30th march 2021. due to the pandemic, it was held online. the organization of the conference started in early 2020, while we were experiencing the lockdown because of covid-19. although the idea to launch a conference on the state of art of contemporary photography was born within the italian research project called memoria fotografica https://www.ifac.cnr.it/images/stories/libri/ar chivio/book/memoria-fotografica.pdf, which was active during 2018-19, a new situation emerged in 2020, therefore also a new involvement. the growing international interest in visual memory was a direct reaction to this change. issues related to photo and film material’s preservation, conservation, investigation, transmission and use became the topics of the conference. contributors were asked to share their recent research and experience on analogue and digital colour photographic and film materials. highlights on preservation, conservation, restoration, digital migration of colour photographs and film were encouraged, including on the following topics: a) historical and current technologies, materials, processes; b) preservation issues and sustainability; c) contemporary photography preservation issues; d) conservation treatments, experiences, case studies; e) emergency preparedness and recovery; f) digitization and digital recovery of photographic objects and film materials; g) research, technologies and new tools in film restoration. the scientific committee of the conference selected 30 oral presentations of 20 minutes each and 16 digital posters given as short presentations of 5 minutes. the conference counted around 140 attendees from 15 countries. the book colour photography and film: sharing knowledge of analysis, preservation, conservation, migration of analogue and digital materials – 2021: conference proceedings, published in august 2021, was a direct outcome of the convening. it came out as part of the open access research culture and science books (available here: https://www.rcasb.eu/index.php/rcasb/catalog/book/1). the scientific committee, whose contribution had a great impact on the success of the event, was then invited to select the most significant papers in order to publish a special issue of the colour culture and science journal (ccsj), where the extended contributions were submitted to a double blind peer reviewing process before their publication. the same process was applied to two additional papers, which were selected among the external submissions because they were found to be important to the advancement of the field. 6 color culture and science journal vol. 14 (1) issn 2384-9568 the present special issue of the journal covers the history of photographic process, their technicality and practise, nowadays nearly lost: nayla maaruf, maria kokkori, and sylvie pénichon investigated the principles of the flexichrome color process; laura covarsì the jos-pe collection found at the rijksmuseum of amsterdam; while nicholas le guern discussed the three colour kodachrome, one of the most iconic and widely missed process; nadezhda stanulevich deepened the knowledge on the versatile additive process created by prokudin-gorskii. the history of motion film processes was also investigated through the work of paolo tosini, who described and discussed the conservation of prizma color films found in the mexican national film archive; while louisa trott outlined the birth of the color motion photography for the amateurs. simone venturini and serena bellotti, as well as david pfluger, lutz garmsen and giorgio trumpy, presented two papers dedicated to the necessity of a wider view on the film and non-film material that are fundamental to achieve a philological restoration and the restoration and digital methods involved in the reconstruction of lenticular films, respectively. two extra conference papers were also admitted to the current special issue. they were by sabrina negri, who explored the conservation of the experimental hand painted films by stan brakhage, and ivan magrin-chagnolleau, who presented a pedagogical approach to photo retouching and colour grading. as editors of this special issue, we would like to remind you all that ccsj is a double diamond publication and that all the contributors and scholars involved in the peer reviewing process act as volunteers, in the present case, for the empowerment of the preservation, conservation, restoration and science of the photography and film community. barbara cattaneo opificio delle pietre dure via f. strozzi, 1 (fortezza da basso) 50129 firenze, italy barbara.cattaneo@beniculturali.it marcello picollo istituto di fisica applicata “nello carrara” del consiglio nazionale delle ricerche (ifac-cnr) via madonna del piano, 10 50019 sesto fiorentino, firenze, italy m.picollo@ifac.cnr.it 7 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110101 contemporary architecture and colour: final definitions for mapping intent marco borsotti 1 1 detp. of architecture and urban studies/dastu, politecnico di milano. marco.borsotti@polimi.it corresponding author: marco borsotti 1 (marco.borsotti@polimi.it) abstract the focus of this study is to define and map out design intent using occurrences of practice that are strongly representative of the adoption of chromatic devices intended as instruments capable of identifying and making legible (in previous contributions we talked about amplification of meaning) the conceptual principles that define the foundation of the design process of an architectural project, as well as to keep them explicit in their formal outcomes. keywords architecture, color, mapping intent received 16 october 2018; revised 15 february 2019; accepted 25 february 2019 citation: borsotti, m. (2019). contemporary architecture and colour: final definitions for mapping intent. color culture and science journal, 11(1), 7–18. https://doi.org/10.23738/ccsj.110101 contemporary architecture and colour: final definitions for mapping intent 8 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110101 1. introduction this text illustrates the third and final contribution – the first and second appeared in colour and colorimetry viii (borsotti in rossi, siniscalco, 2012) and colour and colorimetry x volumes (borsotti, in rossi, marchiafava, 2014) – on the reflection that, moving between identification of contemporary paradigmatic case studies and hypotheses of classification of their outcomes within defined areas referring to common attitudes, look at the use of colour as a true design tool; a real “material” for the realisation of an architectural program. the focus of this study is to define and map out design intent using occurrences of practice that are strongly representative of the adoption of chromatic devices intended as instruments capable of identifying and making legible (in previous contributions we talked about amplification of meaning) the conceptual principles that define the foundation of the design process of an architectural project, as well as to keep them explicit in their formal outcomes. this is an exploration which undoubtedly moves beyond the common concept that, in contemporary architectural production, the use of colour is a choice of pure and simple superficial finish, applicable, case by case, according to extemporaneous aesthetic matrices. the use of colour should, instead, be recognised as a fundamental tool for tracing, with regards to the recurrence of mutually assimilable solutions, the emergence of trends inscribed within precise design communication intentions. after retracing and defining a few potential scenarios such as iconic urban, spot colour, palette colour, differently residential colour, perspective colour, edge colour, immersive colour and translucent colour, here is an outline of the remaining possible categories. (borsotti in rossi, siniscalco, 2012) (borsotti, in rossi, marchiafava, 2014) first of all we must underline the necessary premise that the results of this study do not claim to define a definitive tool for the use of colour in architecture, since this remains, above all, an expression and representation that adheres to geographic and temporal socio-cultural and traditional phenomena, as well as the consequence of the availability of different materials and technologies and the direction of various cultural trends, inevitably linked to the make-up of each designer's personal aesthetic sensibility. the categories here illustrated, derive, rather, from an indepth reflection that seeks to outline the main profiles of the vast contemporary landscape of colour presence in architecture, a research field rarely defined within an overall critical vision and where, instead, homogeneous areas of design practice emerge that should brought back to clear and circumscribable backgrounds and precise intent. 2. container colour architects have always been fascinated by the concept of the container, attempting to grasp how much its characteristics, measurements and constructive structure and standardised volume can become a prefabricated cellular space, easily transportable and aggregable, how to preserve potentially decisive declinations for the definition of modular and serial habitable environments. then there is a further suggestion that comes from the quasi-urban image offered by the transit and storage piers, where the containers, are piled up in large quantities, drawing intricate paths made by large, compact masses. in the numerous and intriguing attempts to transform these visions into an applied architectural project, the presence of colour, already implicit in the original model, plays a fundamental role. on the one hand, the use of the “container icon” preserves the distinction of the basic module, establishing a communicative system of immediate and evident readability that leads back the inhabitable aggregation within its dimensional and structural components and, on the other, defines a clear recognisability of its modularity, which helps to make the architectural fronts more dynamic allowing for a very strong “personalisation” of the housing aggregates. a paradigmatic example of this architectural choice is the housing complex built in carabanchel (madrid, spain) by amann-canovas-maruri architects, where the entire building is designed according to overlapping linear sequences of environments created with metalworking structures, the colours of which have been chosen by the building users themselves. the alternating rhythm of empty and full, defined by the insertion of terraced spaces between one residential module and the other, is strongly emphasised by these chromatic sequences which, to better preserve their nature of compact coloured backgrounds, do not even suffer the interference of full-height windows. these, in fact, are cleverly integrated into the metal structure of the external cladding, while the intermediate string courses, dark and thick, define the linear syntax of a supporting grid on which the individual housing units, each one recognisable by its own colour, appear literally contemporary architecture and colour: final definitions for mapping intent 9 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110101 “supported”, within a sort of optical play on structural equilibrium. this principle affirms the architectural breakdown of the volumes into the summation of their constitutive industrial parts, revealing the desire to produce a habitable system according to the box-in-box principle, where colour is precisely the revealing tool of this choice. there are many illustrious examples prior to this. take for example the most apparent experiments of the so-called container city of trinity buoy wharf (2001) in london, as well as the sophisticated concepts in holland, mvrdv, such as silodam (2002) or the cancer centre (2005) both in amsterdam, which converge towards their great container city project, a potential “cargotecture” for rotterdam city, consisting of 3500 used containers. even when the base matrix of the container is more a conceptual and ideological reference than a direct structural reality, the iconic force of its presence remains fundamental and is explained precisely by the free chromatic assemblage that underlies it, as it happens, for example, in the box 298 office building designed by andrade morettin arquitetos associados in vila madalena (são paulo, brazil). here, indeed, the stated intent to improve the visual perception of the space and place where the building is located, adopts the container colour array to mark, according to a vertical “cascade” sequence (as in a threedimensional game of tetris), coloured surfaces made by corrugated sheet that saturate the full portions of the building, thus reinforcing the presence of the large glazed partitions, sometime left free to generate empty terraced spaces. 3. deep colour a chromatic insertion is often used, in the overall system of a building, as a planning tool to define its constituent rhythm. the presence of a colour, a fact that is inevitably evident and immediately readable, acts, indeed, as a real visual marker the task of which is to highlight and “bring out”, right on the surface of the building, the geometric rules which give shape to the construction of the conceptual design of the project. fig. 1. box 298 office building, vila madalena (são paulo, brasil, 2009). courtesy by andrade morettin arquitetos associados©, nelson kon photographer©. contemporary architecture and colour: final definitions for mapping intent 10 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110101 the chromatic intervention arises as an action that must be coordinated with the understandability of the design principles that drive the creation of the entire architectural structure and help to maintain its evidence. the opportunity offered by the chromatic definition of architectural elements (clearly attributable to the sequence of empty and full spaces that characterise the assembling phase of the geometrical elements, as well as of the structural components) therefore represents a powerful instrument of explicit representation of the linguistic rules that are at the heart of the project. a paradigmatic example is the realization of the new volume of the gymnasium of the middle school complex in riva san vitale (switzerland), designed by architects durisch and nolli. here we find a double-body building where the inner and self-supporting one, which houses classrooms and sports equipment, is completely included within an external casing, which assumes the task of designing a compact and homogeneous façade. the great formal clearness of this external body, a rectangular base prism with a double-height portion, is marked by a linear succession of thick, high and narrow slabs, which make the façade dynamic, making the constructive system clear, where once again the theme of the concrete pillar-lintel is proposed, taken from the existing middle school. the presence of this system is reproduced on the façade through the repetition of an identical module, which can be assembled to infinity, the rigorous consistency of which is underlined and modelled by the insertion of a lively chromatic palette applied just on the inner faces of pillars, to underline the vacuous portions. it is this continuity, immutable in its measurements, but vivaciously varied in its colours, that immediately makes the reading of the geometric coherence of the whole system apparent. a different model of composition characterises another municipal building for sporting activity, designed by gana arquitectura in vélez-málaga (spain), consisting of a compact and translucent space that takes the shape of from a homogeneous one with an alternation of prismatic bodies. . fig. 2. gymnasium of the middle school complex, riva san vitale (switzerland). courtesy by durisch and nolli architects©, tonatiuh ambrosetti photographer©. contemporary architecture and colour: final definitions for mapping intent 11 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110101 in this example as well, the rhythm generated and the reading of the full and empty spaces that distribute the mass of the building, otherwise marked by an almost impenetrable material-visual consistency (which also integrates the opening surfaces, of which only the frames are distinguishable) is affirmed by the use of a strong chromatic presence, realised by using bright ochre yellow, bringing out an effect of extreme dynamism of the volume’s depth and its luminous contrasts. emmanuelle moureaux, whose work is intrinsically linked to the use of colour as an essential part of her conceptual development process of the architectural idea, presents a research path that explores the emotional and perceptive potential of chromatic/architectural systems. in her work this system is defined by involving lines and surfaces to reach a more three-dimensional vision, where it is not simply the linear extension that is marked, but the volumetric depth of the building. in this way, the colour properly assumes the role of marker element capable of unveiling the geometric and rhythmic matrix of the alteration of an initial primary stereometric volume. “i use colours as three-dimensional elements, like layers, so as to create spaces, not as a final touch applied to surfaces ». (moureaux, n.d.) fig. 3. sugamo shinkin bank, tokiwadai (tokyo, japan, 2010). courtesy by emmanuelle moureaux architecture+design©. contemporary architecture and colour: final definitions for mapping intent 12 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110101 fig. 4. sugamo shinkin bank, nakaoki (kawaguchi, japan, 2014). courtesy by emmanuelle moureaux architecture+design©. the offices of the sugamo shinkin bank at tokiwadai (tokyo, 2010) and at nakaoki (kawaguchi, 2014) could be interpreted as the positive or negative of the same architectural reasoning: the thought of how to treat the volume, in the case of the first building an excavation and subtraction process of cubic and splayed portions of the volume while in the second an extrusion and addition of equally cubic jutting out elements, is revealed and emphasised by the use of colour. colour is used where the homogeneity of the basic stereometric matrix is undermined and it enhances the perceptive depth of a volumetric system that seeks a strong dynamic tension in space, involved and reshaped in its physical depth. 4. expressive colour colour is an essential part of a large number of artistic phenomena, thus, without delving too deep into field definitions that refer to other disciplines, we can reasonably state that colour marks and substantiates in itself the artistic presence as instrument and expression of relationships between nature and abstraction, between representation and suggestion. it is therefore particularly interesting to observe what happens when artists and architects meet each other in the field of architectural design, finding in the chromatic device a common field of comparison. it is also interesting to verify how often, in the variety of experiments and experiences, it is possible to find such a contemporary architecture and colour: final definitions for mapping intent 13 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110101 constant in the intense expressive use of the colour, aimed to the valorisation of cultural and territorial content. analyzing some of the numerous traceable case studies, in fact, it is possible to notice how the use of color (a natural act for an artist), when applied to architecture often takes on large scale connotations (both dimensional and social), activating as a "highlighter" that underlines and reveals the role of architecture, the built environment, even in its most urgent critical issues, integrating with it to generate new, unexpected and sometimes fascinating conditions of livability. particularly paradigmatic, not just for its expressive power, is the work by artist pipilotti rist and architect carlos martinez, both swiss, in the raiffeisen square in st. gallen (switzerland, 2003-2005), shaped as a place which, while remaining entirely an urban system integrated into the city, assumes the disruptive and poetic force of a permanent installation stretched across a vast scale, combining these two souls, apparently distant, precisely through the implementation of intense monochromatic intervention. a large red surface covers and defines a broad portion of the city, incorporating everything, from the road surface to urban furniture, to cars and fountains, creating uniformity between the more typical elements, often in disorder and dissonance, of the cityscape with those that are, instead, elements of a more interior domestic character, such as sofas, and tables. all these presences come together to form, finally, “soft” in their form and substance, thanks to the use of a rubbery material, composed of various layers of rubber granules, glue and particular colour choices. the result is a “different” urban space, strongly abstract, yet concretely linked to well-defined functions, explicitly cited with nomenclatures that refer to old and new attitudes of the public place: “reception”, “foyer”, “sculpture park” and “reading corner”. the large square and the streets nearby become a unifying vision, a different way of understanding the “urbanity”, imbued with a habitable comfortable interior and the colour is its most obvious statement: a poetic expression that also becomes a critical reflection on the daily reality of the conformation of the contemporary city. although included into a completely and dramatically different urban context, the intervention that the multidisciplinary collective boa mistura realised in 2012 at the favela vila brasilândia of são paulo (brazil), take form from a very similar conceptual assumption. conceived as a recognisable sign of the affirmation of a collective conscience, this urban artistic intervention subverts the apparent rules of a disadvantaged everyday life, replacing them with the deeper values of its daily experience, represented by the discovery of words chosen to represent the feelings that the inhabitants of the favela share. fig. 5. luz nas vielas (poesía), favela vila brasilândia, são paulo (brazil, 2012). courtesy by boa mistura©. in this way, an alternative model of humanity is opposed to an urban failure that transforms the architecture of living, (here uncertain, minimal and self-built), by introducing a poetic reaction. again, colour is the medium, powerful and immediate, used to initiate this reaction, a bearer of identity and territorial affirmation. luz nas vielas (light in the alleys) is a collective intervention that involved the inhabitants of the favela in all phases of its implementation. people are encouraged to paint alleys and streets with vivid and bright colours, applied by brush and roller directly on the improvised conglomerates that make up its houses, to redefine them, through large chromatic backgrounds from which emerge graphic signs that, by adopting the technique of contemporary architecture and colour: final definitions for mapping intent 14 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110101 anamorphism, in a single fleeting point of view, conquer form and legibility of words. «the project aims to respond to this characteristic spatial complexity [defined] by narrow, winding corridors that connect the upper and lower urban areas, known as “vielas”. flattening the perspective from one point (anamorphism), the words “beleza”, “firmeza”, “amore”, “doçura” and “orgulho” are read and framed by a flat colour, which covers all the building materials in the same way, democratising space. for us, these words are the best portrait of the favela». (boamistura, n.d.) the many works of urban re-interpreting boa mistura, almost always adopt the convergence of writing and colour in order to literally return the words themselves to places, transforming them from unfinished or forgotten landscapes into narrative spaces. the colour intervention is no mere application tool. it is a clear stance: its use, its presence, redefines the spaces by enveloping them in a renewed spatiality. in the intervention carried out for the restructuring of the mercado de la cebada, in madrid (spain, 2013) the two main façades and the six large concrete domes of the public building, built in 1958 and, at that age, in a state of serious architectural decay, have been transformed by the disruptive appearance of colour, which characterises each dome with a different shade, and by the appearance of the writing “llena la vida de color” (fill life with colour) and “colour”. the latter again takes shape on the domes thanks to the anamorphism. the artistic-architectural action expresses the intent to restore visibility to the building and thus reaffirm its social role, subverting the process of abandonment that had brought it to the brink of demolition and, instead, supporting the process of recovery. “we have changed the colour of each dome, thereby modifying the landscape of the area. colours show optimism and somehow highlight what is happening on the market.”. (boamistura, n.d.a) contemporary architecture and colour: final definitions for mapping intent 15 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110101 fig. 6. luz nas vielas (poesía), favela vila brasilândia, são paulo (brazil, 2012). courtesy by boa mistura©. fig. 7. luz nas vielas (orgulho), favela vila brasilândia, são paulo (brazil, 2012). courtesy by boa mistura©. colour, therefore, is a visual structure capable of activating narratives that intersect with the physical substance of the architecture, with its being a form that occupies and modifies space, but also a fragile trace of individual and collective histories, perpetually exposed to erosion of matter as well as multiple and often contradictory or insensitive interests (such as flows of economic interests). a chromatic intervention can disturb the rules of everyday life, it can destabilise the constructed landscape by transforming some of its consolidated components (often made invisible by a process of careless additions) into a vibrant presence, into truly evocative manifestos. this is why amanda williams, an african-american visual artist with an architect's background, works on old houses destined for demolition in the south side of chicago – an artistic action that takes the name of color (ed) theory series – repainting them completely, intervening on each one with a single bright colour, belonging to a signature palette of eight colours, to claim its existence and, in a way, to honour the buildings’ last moments. «i wanted to mark the final act of the end of the era of a black space (...) the architecture in some neighbourhoods is characterised by a process of removal, not addition». (sargent, 2015) these are artistic acts which do not intervene in the architectural project, but in the architectural reinterpretation of the existing signs, in order to clearly mark their imminent end and trace their historical significance within the urban landscape. at the same time these acts aim to generate questions about the dynamics that have progressively erased a “black” neighbourhood (today there are over five thousand lots stripped of human and architectural presence), whose final moments are celebrated by using colour, which elevates them to the temporary rank of works of art, for their value as fragments of the cultural memory of traditionally africanamerican spaces. “what colour is urban? what colour is gentrification? what colour is privilege? what colour is poverty? looking for answers, i painted abandoned houses in the south side of chicago using a monochromatic colour palette that is culturally coded (...) i am working on a system that imagines original ways to build new narratives for landscapes with zero value, which will allow them to free themselves from the identity of the victim and embrace the role of active protagonist». [7] 5. conclusions the three instances of this investigation into the use of colour in contemporary architecture (see note 1) have helped to circumscribe some common design methods, where chromatic intervention represents the foundation of the project’s intention and become a fundamental tool of its realisation. now, we can draw a number of overall conclusions that stem from the study as a whole. first of all, we can confirm that there is a close relationship between the foundational conceptual intent of some design processes and the identification of the use of colour as a programmatic choice deemed necessary in order to sustain and explain these intentions. colour, therefore, must be seen as an integral part of the idea of architecture, and not as a mere accessory. furthermore, we have seen some design process areas where colour finds a clear correspondence with its final 16 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110101 configuration in view of the overall architectural intervention realised and with the ideal objective with which they were conceived and realised, thus defining the research field itself. fig. 8. mercado de la cebada, madrid (spain, 2013). courtesy by boa mistura©. the many categorisations referred to, in fact, identify some of the main thematic areas in which they find obvious application: the urban iconic (colour as a concrete element of affirmation of recognisability within the urban fabric) and the immersive colour (colour as a prevalent and allencompassing component) represent two, sometimes overlapping, attitudes, where architecture defines its own evident role in the context through a predominant chromatic presence: here colour engages the whole building affirming its indisputable iconic presence. therefore, through colour, a principle of unequivocal and evident relationship is established between the architectural complex and its context. we can also say that the different residential colour (the intensive use of colour devices characterising the new concept of social housing) is a category that has the same intention of selfaffirmation, developed, not by chance, in a specialised typological field. here, in fact, colour (usually satisfying a need for personalisation and recognition relating to the individuality of a single complex inhabitant) is used, instead, to underline and unequivocally support the strongly experimental and innovative character of these new housing forms. the spot colour (colour as an architectural marker, that clearly defines the fundamental elements of a design) places the chromatic intervention at the heart of the visual-interpretative system of an architectural complex, recognising it as a mediator capable of underlining all the devices of the architectural composition and form, adopted in the definition of the building. it acts as a sort of “architectural-scale highlighter”, which underlines the project’s “key words”, according to an overall and omni-comprehensive process of which the perspective colour (colour as an exaltation of the threedimensional depth of the space), the edge colour (colour as a reinforcement of the margins) and the deep colour contemporary architecture and colour: final definitions for mapping intent 17 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110101 (color as a scan of empty and full spaces) are not so much sub-categories, rather they are more specifically adjectivisations, which consolidate and provide a better and more spontaneous understanding, precise ideological-conceptual choices. in these categories, therefore, colour seems to be a code that truly declares architectural principles. the palette colour (color as a “palletised” -colour communication system) and the container colour (colour that states the principle of the “box in a box”) represent the most multicolour and geometric outcomes of “coloured architecture”. in this case we are faced with an architecture punctuated by the adoption of modules (in the first case more related to the façade while more connected to compositional choices in the second case) the repetition of which is emphasised by the continuous combination of different colour shades. the resulting visual impact is expressed in the clear reading of the rhythmic scanning of a composition and in the perception of a potentially infinite tension of these chromatic sequences. these ones are also present in the assembly phase of their parts, thanks to the visibility of the margins defined by the geometric meshes adopted, which, in the case of the container colour, also often have a three-dimensional correspondence (hence “habitable”). the translucent colour, apparently unrelatable to the previous categories, is in the same conceptual framework that thinks about the material nature of colour and its density, exploring its inherent potential in the transition from compact texture (which delineates and delimits a surface) to a porous and “traversable” system (for light, reflections, images). here, there is an intentionality to delve deeper into the idea of spatiality, designed as a layering of layers, which, as on a computer screen, are distinguished and managed through the attribution of different colours. in brief, these are three categories that meditate on the visual and perceptual physicality of colour as “building material”. the expressive colour, finally, enters the “middle world” where architecture meets art, to see how urban and territorial redesign contexts, in the vastness of their experiences and situations, often find a place of convergence in the use of colour, which adheres to the construct following and formalising the intuitions of the artist. thus are triggered phenomena of reinterpretation of the constructed landscape, which amplify the artistic sensitivity to the definition and virtual (and sometimes real) change of its spatiality, thanks to the chromatic addition. this modifies the usual point of view, exposing its weaknesses and hypocrisies through the grafting of different narrative phenomena, sometimes innovative, but more often "dormant". colour as an affirmation, even a political one, of the architecture’s role. conflict of interest declaration all authors of the color culture and science journal (ccsj) are requested to disclose any actual or potential conflict of interest including financial, personal or other relationships with other people or organizations within three years of beginning the submitted work that could inappropriately influence, or be perceived to influence, their work. the conflict of interest declaration must be included in the paper and states if no financial/personal interests have affected the objectivity of the author(s), or if there are, the source and nature of the potential conflicts. authors must state explicitly whether potential conflicts do, or do not exist. funding source declaration this research did not receive any specific grant from funding agencies in the public, commercial, or not-forprofit sectors. notes [1] m. borsotti (2012). architetture contemporanee e colore: amplificazioni di senso. in: m. rossi, a. siniscalco. colore e colorimetria. contributi multidisciplinari vol. viii a. alma mater studiorum, università di bologna, facoltà di ingegneria, bologna, 13/09/2012 14/09/2012, p. 315-322, milano: maggioli editore, isbn: 8838761361 and borsotti, m. (2014). architetture contemporanee e colore: altre amplificazioni di senso. in rossi m., marchiafava v. (ed), colore e colorimetria. contributi multidisciplinari. vol. x a. atti della decima conferenza del colore. università degli studi di genova. (pp. 511518) santarcangelo di romagna (rn): maggioli. isbn 97888-9160437-8 [2] idem [3] emmanuelle moureaux, shikiri. dividing and creating space through colors. see: retrieved from: http://www.emmanuellemoureaux.com/shikiri/ (consulted 1/4 2016) [4] retrieved from: http://www.boamistura.com/luz_nas_vielas.html (consulted 1/4 2016) [5] retrieved from: http://www.boamistura.com/color.html (consulted 1/4 2016) [6] antwaun sargent, amanda williams' color theories. retrieved from: http://www.interviewmagazine.com/art/amanda-williams-color-theories/ (consulted 1/4 2016) [7] amanda williams, color(ed) theory series. retrieved from: http://awgallery.com/section/373029-color-ed-theory-series.html (consulted 1/4 2016) short biography marco borsotti is an architect and interior architecture & exhibit design ph.d. contemporary architecture and colour: final definitions for mapping intent 18 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110101 he is associate professor at department of architecture and urban studies (dastu), school of architecture urban planning construction engineering, politecnico di milan (italy). he takes part in national and international research projects and conferences on his main research field: interior & exhibit design, contemporary inhabiting and contemporary sacred spaces. articles, essays and projects have been published by specialized review. references boamistura (n.d.) "luz nas vielas" (light in the alleyways). available at: http://www.boamistura.com/#/project/luz-nas-vielas-2 (accessed: 10 october 2018) boamistura (n.d.a) llena la vida de color. the dome. available at: http://www.boamistura.com/color.html (accessed: 10 october 2018) borsotti, m. (2012) ‘architetture contemporanee e colore: amplificazioni di senso’, in: rossi m., siniscalco a. (ed.) colore e colorimetria. contributi multidisciplinari vol. viii, a. santarcangelo di romagna (rn): maggioli, p. 315-322. (isbn: 8838761361) borsotti, m. (2014) ‘architetture contemporanee e colore: altre amplificazioni di senso’, in rossi m., marchiafava v. (ed), colore e colorimetria. contributi multidisciplinari. vol. x a. atti della decima conferenza del colore. santarcangelo di romagna (rn): maggioli, pp. 511518. (isbn 978-88-9160437-8) moureaux e. (n.d.) concept. shikiri. dividing and creating space through colors. available at: http://www.emmanuellemoureaux.com/shikiri/ (accessed: 10 october 2018) sargent a. (2015), amanda williams' color theories. available at: http://www.interviewmagazine.com/art/amanda-williams-color-theories/ (accessed: 10 october 2018) williams a. (n.d.) work. color(ed) theory series. available at: https://awstudioart.com/section/373029-color-ed-theory-series.html (accessed: 10 october 2018) anderson feisner e., reed r. (2004), color studies. london: fairchild books albers j. (2013) interaction of color: 50th anniversary edition. yale: yale university press arnheim r. (2008) arte e percezione visiva. nuova versione. milano: feltrinelli birren f. (1961) color psychology and color therapy. a factual study of the influence of color on human life. seattle: university books brusatin m. (2000), a history of colors. torino: einaudi falzone p. (2008) colore architettura ambiente. roma: edizioni kappa glasner b., schmidt p. (eds.) (2009), chroma: design architecture & art in color. basel: birkhäuser. goethe von, j. w. (1987), la teoria dei colori: lineamenti di una teoria dei colori. milano: il saggiatore itten, j. (1961) the art of color: the subjective experience and objective rationale of color. new york: john wiley & sons komossa s., rouw k., hillen j. (2009). colour in contemporary architecture. amsterdam: sun publishers linton h. (1999) color in architecture: design methods for buildings, interiors, and urban spaces. new york: mcgraw-hill. porter t., mikellides b. (eds.) (2009). colour for architecture today. new york: taylor & francis rahim a. (2001) contemporary tecniques in architecture, new york: johnwiley & sons sandu cultural media (eds) (2012), color and space. berkley/hamburg: ginko press cultura e scienza del colore color culture and science 07 17 riv is ta s em es tr al e | h al fye ar ly jo ur na l | d o i: 10 .2 37 38 /c c sj .0 0 rivista dell’associazione italiana colore www.gruppodelcolore.it doi: 10.23738/ccsj.i72017.00 cultura e scienza del colore color culture and science 07numero 07 june 2017 number 07 june 2017cultura e scienza del colorecolor culture and science rivista semestrale dell’associazione italiana colore http://jcolore.gruppodelcolore.it/ issn 2384-9568 doi: 10.23738/ccsj.00 direttore responsabile | editor-in-chief maurizio rossi (politecnico di milano, it) redazione | associate editors aldo bottoli (b&b colordesign, it) daria casciani (politecnico di milano, it) davide gadia | deputy editor (università degli studi di milano, it) marco gaiani (università di bologna, it) veronica marchiafava (associazione italiana colore, it) silvia piardi (politecnico di milano, it) alessandro rizzi (università degli studi di milano, it) francesca valan (studio valan, it) editorial board members john barbur (city university london, uk) giovanni bartolozzi (ifaccnr, it) berit bergstrom (ncs colour ab, se) giulio bertagna (b&b colordesign, it) janet best (natific, uk) aldo bottoli (b&b colordesign, it) patrick callet (école centrale paris, fr) jean-luc capron (université catholique de louvain, be) daria casciani (politecnico di milano, it) osvaldo da pos (università degli studi di padova, it) bepi de mario (crasmi, it) hélène declermont-gallernade (chanel parfum beauté, fr) reiner eschbach (xerox, usa) alessandro farini (ino-cnr, it) christine fernandez-maloigne (university of poitiers, fr) renato figini (konica-minolta, eu) raffaella fontana (ino-cnr, it) davide gadia (università degli studi di milano, it) marco gaiani (università di bologna, it) robert hirschler (serviço nacional de aprendizagem industrial, br) sandra krasovec (fashion institute of technology, usa) francisco imai (canon, usa) matteo lanaro (università degli studi di milano, it) lia luzzatto (color and colors, it) kevin mansfield (ucl, uk) veronica marchiafava (associazione italiana colore, it) cultura e scienza del colore color culture and science rivista dell’associazione italiana colore registrazione presso il tribunale di milano al n. 233 del 24.06.2014 gabriel marcu (apple, usa) anna marotta (politecnico di torino, it) manuel melgosa (universidad de granada, es) anna grazia mignani (ifac-cnr, it) annie mollard-desfour (cnrs, fr) maria luisa musso (universidad de buenos aires, ra) claudio oleari (università degli studi di parma, it) galina paramei (liverpool hope university, uk) laurence pauliac (historienne de l’art et de l’architecture, paris, fr) silvia piardi (politecnico di milano, it) marcello picollo (ifac-cnr, it) renata pompas (afol milano-moda, it) boris pretzel (victoria & albert museum, uk) noel richard (university of poitiers, fr) katia ripamonti (cambridge research system, uk) alessandro rizzi (università degli studi di milano, it) maurizio rossi (politecnico di milano, it) jodi l. sandford (università di perugia, it) raimondo schettini (università degli studi di milano bicocca, it) gabriele simone (st microelectronics, it) andrea siniscalco (politecnico di milano, it) ferenc szabó (university of pannonia, hu) mari uusküla (tallinn university, ee) francesca valan (studio valan, it) ralf weber (technische universität dresden, de) alexander wilkie (charles university in prague, cz) peer review process tutti gli articoli inviati alla rivista “cultura e scienza del colore color culture and science” sono sottoposti ad un processo di revisione secondo la seguente procedura: prima revisione gli associate editors valutano ogni articolo per determinare se il tema e il contenuto sono di interesse per la rivista “cultura e scienza del colore color culture and science”. una volta valutati gli articoli, gli associate editors selezionano una serie di revisori scegliendoli scegliendoli nell’editorial board in base all’esperienza degli stessi in un particolare settore disciplinare o tema. seconda revisione ogni articolo è revisionato da due revisori in un processo in cui essi stessi e gli autori sono mantenuti anonimi. ai revisori è chiesto di valutare l’articolo considerando la sua originalità, la metodologia applicata e l’impatto sulla ricerca o sulla pratica professionale. dopo aver raccolto i commenti dei revisori, gli associate editors elaborano ed inviano al direttore responsabile un giudizio riassuntivo sull’accettazione o meno dell’articolo. collaboratori | contributors fabrizio apollonio, andrea ballabeni, osvaldo da pos, motonori doi, marco gaiani, akira kimachi,michela lecca, anna marotta, shogo nishi, renata pompas, jodi l. sandford, anna luana tallarita editore | publisher gruppo del colore – associazione italiana colore www.gruppodelcolore.it sede legale: piazza carlo caneva, 4 20154 milano (italia) all articles submitted to “cultura e scienza del colore color culture and science” journal are peer-reviewed according to the following procedure: first review the associate editors evaluates each article in order to define if the topic and content is suitable for consideration by the “cultura e scienza del colore color culture and science” journal. once the article passes the initial review, the associate editors select several referees in the editorial board based on their expertise in the particular field or topic second review each article is reviewed by two or three referees under a double-blind peer review process where the authors and the reviewers are kept anonymous. referees are asked to evaluate the manuscript based on its originality, methodology and impact to research and relevance to the professional practice. after collecting the referees’ reports, the associate editors makes a recommendation on the acceptability of the article to the editor in chief. doi: 10.23738/ccsj.i72017.00 gruppo del colore associazione italiana colore sommario | summary english | italian review 07 5 7 13 29 39 59 69 78 80 editorial by maurizio rossi red: the symbol in history rosso by anna luana tallarita art and colour in the requalification of urban areas and landscapes arte e colore nella riqualificazione della città e del paesaggio by anna marotta using color and local binary patterns for texture retrieval by michela lecca specular reflection removal in the context of sfm techniques for architectural heritage 3d models construction by fabrizio apollonio, andrea ballabeni, marco gaiani image registration for a multispectral imaging system using interference filters and application to digital archiving of art paintings by shogo nishi, akira kimachi, motonori doi color categorial perception and second language acquisition by jodi l. sandford michel pastoureau “rosso. storia di un colore” by renata pompas communications and comments by michela lecca and osvaldo da pos coloumn english 4 cultura e scienza del colore color culture and science | 07 | 2017 issn 2384-9568 this page has been intentionally left white 5 cultura e scienza del colore color culture and science | 07 | 2017 issn 2384-9568 la rivista cultura e scienza del colore, edita dalla associazione italiana colore, con questo numero 7 è approdata al quarto anno di pubblicazione. stiamo proseguendo con il processo di miglioramento qualitativo finalizzato ad ottenere l’accreditamento internazionale. la rivista è entrata a far parte del repertorio delle riviste open access road. inoltre dichiara dal 2015 sul suo sito internet il suo metodo di peer review e il suo codice etico. in questo numero proseguiamo con la nostra politica multidisciplinare sui temi inerenti il colore, la luce e la percezione visiva che sono fondativi dell’associazione italiana colore. anna luana tallarita ci presenta un saggio con una proposta di analisi storica originale sul colore rosso, partendo dall’etimologia della parola e arrivando ad una analisi della simbologia del rosso nelle religioni. anna marotta propone un’interessante ricerca sul tema del progetto colore per il recupero e la riqualificazione urbana con particolare attenzione alle periferie; la trattazione si sviluppa tra l’analisi di casi studio di luoghi e le esperienze di street art. il tema del riconoscimento dei materiali, tramite le tessiture, nelle immagini del mondo reale, a prescindere dalle condizioni di illuminazione, è al centro della ricerca scientifica presentata da chiara michela lecca; il metodo proposto, sperimentato su dati di pubblico dominio, conferma che l’utilizzo congiunto della informazione cromatica e delle caratteristiche della tessitura, migliora le capacità di riconoscimento dei materiali. fabrizio ivan apollonio, andrea ballabeni e marco gaiani presentano una ricerca nel contesto del rilievo fotogrammetrico, proponendo un metodo per la rimozione delle riflessioni speculari e degli highlight dalle immagini; la proposta è inserita nell’ambito di un metodo di lavoro finalizzato all’acquisizione di modelli 3d digitali del patrimonio architettonico. nel contesto dell’imaging multispettrale, applicato all’archiviazione digitale dei dipinti, shogo nishi, akira kimachi e motonori doiche presentano un metodo per la calibrazione di sistemi di acquisizione multispettrale, che utilizza filtri interferenziali, per la stima delle proprietà superficiali, come la riflettanza spettrale e le normali. infine jodi l. sandford, nell’area della ricerca sul color naming, presenta i risultati di una serie di esperimenti percettivi e linguistici finalizzati a verificare la percezione categoriale, nomenclatura e comprensione dei termini cromatici, nei bambini di madrelingua italiana editorial the journal color culture and science, published by associazione italiana colore, has just achieved with this issue its fourth year of publication. we are going on with the quality improvement process in order to obtain the international accreditation. we have already joined the index of open access journals road. furthermore, we have declared the peer review method and our ethic code on our website since 2015. in this issue we carry on our multidisciplinary approach on the topics about color, light and visual perception that is in the core of associazione italiana colore statute. anna luana tallarita presents a paper on a proposal for a new historical analysis regarding the red color starting from the word’s etymology and arriving at an analysis of the symbology of red among the religions. anna marotta proposes an interesting research on the subject of color’s design for urban recovery and requalification with particular attention to suburbs; the discussion develops between the analysis of case studies of places and experiences of street art. the topic of the recognition of materials, through textures, in the images of the real world, regardless of the conditions of lighting, is the core of the scientific research presented by chiara michela lecca; the proposed method, experimented on publicly available information, confirms that the combined use of chromatic information and characteristics of textures, improves the ability of recognition of the materials. fabrizio ivan apollonio, andrea ballabeni and marco gaiani present a research in the context of photogrammetric relief, suggesting a method for the removal of specular reflections and highlight from images; the proposal is included as part of a workflow aimed at the acquisition of 3d digital models of the architectural heritage. in the context of multispectral imaging, applied to digital archiving of art paintings, shogo nishi, akira kimachi and motonori doiche present a method for the calibration of systems of multispectral imaging acquisition, that uses interference filters to estimate the surface properties, such as spectral reflectance and normals. finally, jodi l. sandford, in the area of research on color naming presents the results of a series of perceptual and linguistic experiments directed to verify the categorial perception, naming, and comprehension of chromatic terms, for italian mother tongue children who also speak english as a second language. 6 cultura e scienza del colore color culture and science | 07 | 2017 issn 2384-9568 che parlano anche inglese come seconda lingua. nella rubriche, renata pompas presenta la recensione del libro di michel pastoureau “rosso. storia di un colore” mentre michela lecca con osvaldo da pos presentano vari argomenti sul tema “cibo e colore” nelle loro communications and comments. editor in chief maurizio rossi in the columns, renata pompas presents the review of the book of michel pastoureau “rosso. storia di un colore” and michela lecca with osvaldo da pos present various topics on the subject of “food and color” in their communications and comments. editor in chief maurizio rossi color culture and science cultura e scienza del colore ccsj volume 11 number 1 2019 issn 2384-9568 color culture and science (ccsj) cultura e scienza del colore jcolore.gruppodelcolore.it issn 2384-9568 doi: 10.23738/ccsj.00 ance e227716 road: the directory of open access scholarly resources registrazione presso il tribunale di milano n. 233: 24/06/2014 volume 11, number 1, july 2019, doi 10.23738/ccsj.110100 publisher gruppo del colore – associazione italiana colore www.gruppodelcolore.org registered office: piazza carlo caneva, 4 20154 milan (it) peer review process all articles submitted to the " color culture and science journal are peer-reviewed according to the following procedure: first review level the associate editors evaluate each article in order to determine if the topic and content are of interest to the journal. once the article passes the initial review, the associate editors select several referees in the editorial board based on their expertise in a particular subject area or topic. second review level each article is reviewed by two or three referees and submitted to a double-blind peer review process where both the authors and the reviewers are kept anonymous. referees are asked to evaluate the manuscript based on the following criteria:  originality  relevance to journal’s aims and scope  technical merit and/or validity  soundness of methodology  completeness of the reported work  conclusions supported by the data  correct acknowledgment of the work of others through reference  effectiveness of the manuscript (organization and writing)  clarity of tables, graphs, and illustrations  importance to color researchers  relevance to color practices if the article is accepted with major revisions by the referees, the author(s) are asked to improve the article according to the suggestions of the referees. the revised article will then be submitted to a further review. after collecting the referees' reports, the associate editors make a recommendation on the acceptability of the article to the editor-in-chief. editorial board members john barbur (city university london, uk) giovanni bartolozzi (ifac-cnr, it) laura bellia (università di napoli federico ii, it) berit bergstrom (ncs colour ab, se) giulio bertagna (b&b colordesign, it) janet best (natific, uk) aldo bottoli (b&b colordesign, it) josé luis caivano (universidad de buenos aires, ar) patrick callet (école centrale paris, fr) jean-luc capron (université catholique de louvain, be) daria casciani (politecnico di milano, it) vien cheung (university of leeds, uk) paula csillag (espm university, br) osvaldo da pos (università degli studi di padova, it) hélène declermont-gallernade (chanel parfum beauté, fr) reiner eschbach (xerox, usa) alessandro farini (ino-cnr, it) christine fernandez-maloigne (university of poitiers, fr) renato figini (konica-minolta sensing europe, eu) raffaella fontana (ino-cnr, it) davide gadia (università degli studi di milano, it) marco gaiani (alma mater studiorum università di bologna, it) robert hirschler (serviço nacional de aprendizagem industrial, br) takahiko horiuchi (chiba university, jp) sandra krasovec (fashion institute of technology, usa) francisco imai (canon, usa) lia luzzatto (color and colors, it) kevin mansfield (ucl, uk) veronica marchiafava (gdc-associazione italiana colore, it) gabriel marcu (apple, usa) anna marotta (politecnico di torino, it) manuel melgosa (universidad de granada, es) anna grazia mignani (ifac-cnr, it) annie mollard-desfour (cnrs, fr) maria luisa musso (universidad de buenos aires, ra) galina paramei (liverpool hope university, uk) laurence pauliac (historienne de l’art et de l’architecture, paris, fr) silvia piardi (politecnico di milano, it) marcello picollo (ifac-cnr, it) renata pompas (afol milano-moda, it) boris pretzel (victoria & albert museum, uk) noel richard (university of poitiers, fr) katia ripamonti (cambridge research system, uk) alessandro rizzi (università degli studi di milano, it) maurizio rossi (politecnico di milano, it) jodi l. sandford (università di perugia, it) raimondo schettini (università degli studi di milano bicocca, it) verena m. schindler (chair aic s.g. environmental colour design, ch) gabriele simone (renesas electronics europe gmbh, de) andrea siniscalco (politecnico di milano, it) ferenc szabó (university of pannonia, hu) mari uusküla (tallinn university, ee) francesca valan (studio valan, it) ralf weber (dresden university, de) stephen westland (university of leeds, uk) alexander wilkie (charles university in prague, cz) associate editors josé luis caivano (universidad de buenos aires, ar) vien cheung (university of leeds, uk) marco gaiani (alma mater studiorum università di bologna, it) robert hirschler (serviço nacional de aprendizagem industrial, br) marcello picollo (ifac-cnr, it) verena m. schindler (chair aic s.g. environmental colour design, ch) renzo shamey (nc state university, usa) francesca valan (studio valan, it) deputy editor alessandro rizzi (università degli studi di milano, it) editor-in-chief maurizio rossi (politecnico di milano, it) 3 color culture and science journal vol. 11 (1) issn 2384-9568 table of contents editorial 5 maurizio rossi contemporary architecture and colour: final definitions for mapping intent 7 marco borsotti doi: 10.23738/ccsj.110101 color emotion as a feasible tool in a participatory project for a primary school 19 cristina boeri doi: 10.23738/ccsj.110102 'khrôma' the first software for management of the color and decoration plan for small historic villages 28 filippo cherubini, andrea casini, costanza cucci, marcello picollo, lorenzo stefani doi: 10.23738/ccsj.110103 the tropical aquarium: a case of polychrome decoration in the architecture of the early 1900s 35 carlo giannattasio doi: 10.23738/ccsj.110104 evolution of colours in football shirts through colorimetric measurements: fiorentina's case. 41 alessandro farini, elisabetta baldanzi, marco raffaelli, francesco russo doi: 10.23738/ccsj.110105 painted or not painted? discovering color traces of ancient stones 47 susanna bracci, donata magrini, giovanni bartolozzi doi: 10.23738/ccsj.110106 industrial colour invention: a comparative analysis from the perspective of the colourist designer 57 lina perdomo doi: 10.23738/ccsj.110107 4 color culture and science journal vol. 11 (1) issn 2384-9568 how the colours of objects and light affect human emotions, performance and health. the need for a holistic approach to design indoor environment. 67 giuseppe barbato, laura bellia, alfonso morone doi: 10.23738/ccsj.110108 semantic resonance to light sources of different correlated colour temperature 74 pietro fiorentin, osvaldo da pos, elena pedrotti, ariella metellini doi: 10.23738/ccsj.110109 millennial pink: gender, feminism and marketing. a critical analysis of a color trend 82 kévin bideaux doi: 10.23738/ccsj.110110 coloumns review: two books that describe pigments and dyes, in a different and complementary way. 90 renata pompas 5 color culture and science journal vol. 11 (1) issn 2384-9568 editorial having reached the sixth year of life of the "color culture and science journal" (ccsj) it is important to recall the meaning of the concept of double open access underwhich our journal is managed and published: the magazine is completely free for both readers and authors. in a time in which, in order to make money, there are publishers who publish journal and organize conferences without making any control over scientific contents (bauer et al. 2018a, 2018b)(vite, 2018), it is important to emphasize that our policy is diametrically opposed and this is possible thanks to the scientific volunteer work that is guaranteed by some members of the associazione italiana colore, which is a charity. in the previous editorials i described the steps of the evolution process, for the scientific internationalization, which led the journal to be completely in english language and to apply the double blind peer review. the journal is continuing on this path, as the new online organization of papers of this issue shows only in part, such as the top of an iceberg. indeed, below the surface, we are migrating the online journal management system from joomla to ojs in order to better support the peer review process. this also to provide all the information regarding the papers published in the journal, in a more structured way, through compatibility with “open archives initiative protocol for metadata harvesting”. alongside this process, we renewed the board of the associate editors, involving a greater number of international experts for the scientific evaluation and management of the peer review process. the journal is published by a multidisciplinary association that has its points of reference in the themes of color, light and the linked technical-scientific, cultural and professional sectors. also this issue is an example of multidisciplinary integration. as the associazione italiana colore is a regular member of association internationale de la couleur (aic) we involved experts from the aic in the ccsj. the new associate editors are: josé luis caivano, former president of the aic, of the universidad de buenos aires (ar), for the topics in the context of color and culture: arts and crafts, history, philosophy, aesthetics, ethno-anthropology, graffiti, geology, sociology, lexicology, semantics, anthropology of vision, food culture and heritage. vien cheung, vice-president of the aic, of the university of leeds (uk), for the topics of color and digital: reproduction, management, digital color correction, image processing, graphics, photography, film and video production, printmaking and 3d print, artificial vision, virtual reality, multispectral imaging, data visualization. and also for the topics of color and design: furniture, cmf design, fashion, textiles, textures, cosmetics, food design, museography. marco gaiani, of the alma mater studiorum università di bologna (it), for the topics in the wide context of color and environment: representation and drawing, urban planning, project of color, architecture, interior design, landscapes & horticulture, color and architectural syntax, territorial identities, biodiversity. robert hirschler, chair of the aic study group on color education (br), for the topics on color and education: pedagogy, didactics of color, aesthetic education, artistic education, color naming. 6 color culture and science journal vol. 11 (1) issn 2384-9568 marcello picollo, president of the gdc-associazione italiana colore, of the institute of applied physic nello carrara-cnr (it), for the topics that deal with color and restoration: archaeometry, painting materials, diagnostics and techniques of conservation, restoration and enhancement of cultural heritage. verena m. schindler, chair of the aic study group on environmental color design (ch), for the topics regarding color and production: food and beverages, agriculture, textiles, plastic materials, ceramics, paints, gemology, color in the food industry. alessandro rizzi, former president of the gdc-associazione italiana colore, of the università degli studi di milano (it), deal with the topics on color and physiology: mechanisms of vision in their experimental and theoretical aspects, deficiencies, abnormalities, clinical and biological aspects, synesthesia, health, wellbeing. and also the topics on color and psychology: phenomenology of colors, color harmonies, color & form, perceptive, emotional, aesthetic and diagnostic aspects. maurizio rossi, former president of the gdc-associazione italiana colore, of the politecnico di milano (it), for the topics on color and lighting: metamerism, color rendering, adaptation, color constancy, appearance, illusions, color memory and perception, color in extra-atmospheric environments, lighting design, lighting technologies, visual comfort. renzo shamey, of the north carolina state university (usa), is the expert on the fundamental topics of color and measurement, instrumentation: colorimetry, photometry and color atlas: method, theory and instrumentation; quality control and food coloring, dyes, organic and sustainable color. francesca valan, color designer (it), for the topics of color and communication, marketing: graphics, communication, packaging, lettering, exposure, advertising. july, 2019 the editor-in-chief maurizio rossi references bauer, p., krause, t., kropshofer, k., langhans, k., & wagner, l. (2018). das schein-geschäft. angriff auf die wissenschaft. süddeutsche zeitung. retrieved from https://projekte.sueddeutsche.de/artikel/wissen/angriff-auf-die-wissenschaft-e398250/?reduced=true bauer, p., krause, t., kropshofer, k., langhans, k., & wagner, l. (2018, september 21). i predatori della scienza. internazionale, (1274). retrieved from https://www.internazionale.it/sommario/1274 vite, f. (2018, september 22). i predatori della scienza. retrieved 18 july 2019, from il sito di franco vite website: https://francovite.info/2018/09/22/i-predatori-della-scienza/ cultura e scienza del colore color culture and science 47 cultura e scienza del colore color culture and science | 06 | 2016 issn 2384-9568 1valeria biasi valeria.biasi@romascuola.net 2paolo bonaiuto paolo.bonaiuto@uniroma1.it 1department of education, “roma tre” university 2faculty of medicine and psychology emotional qualities of colours added to humorous illustrations abstract many humorous illustrations concerning office work and published in italy in national periodicals and specific books were firstly collected. three typical illustrations were selected and arranged in four versions: black and white; with alarming and serious colorations or reassuring and playful ones, or mixed hues, using acrylics. each version was evaluated individually and given a humour score from 0 (minimum) to 10 (maximum), by 116 university students or ministry employees of both genders. the hypothesis was that average humour scores would be significantly greater with the reassuring and playful colorations, lower with the alarming and serious hues, and intermediate with the mixed colourings or black and white versions. the colorations are based on indications from works by bonaiuto (1978), biasi & bonaiuto (2006), biasi, bonaiuto & giannini (2007), biasi, bonaiuto & levin (2014). the statistical analysis includes means and standard deviations, student t test and others. the results fully confirmed the working hypotheses. keywords emotional qualities, colours, humorous illustrations, reassuring and playful colours, alarming and serious colours citation: biasi v. and bonaiuto p. (2016) ‘emotional qualities of colours added to humorous illustrations’, cultura e scienza del colore color culture and science journal, 06, pp. 47-52, doi: 10.23738/ccsj.i62016.04 received 2 february 2015; revised 13 october 2015; accepted 21 october 2015 valeria biasi is professor of general psychology at the department of “education” of the “roma tre” university. she is member of the italian association of psychology (aip) and the education research society (sird). hes research interests include the study of psychological conflict, affective and cognitive processes, and, in particular, psychology of perception. prof. paolo bonaiuto is, from 1975, full professor of general psychology at “la sapienza” university of rome. he has made many scientific contributions on psychology of perception amd motivation. he has distinguished “alarming colours” and “reassuring colours”, conducting experiments on their functional effects. he has promoted studies of the psychology of visual arts, architecture, dance and humor. 48 cultura e scienza del colore color culture and science | 06 | 2016 | 47 52 biasi v. and bonaiuto p. issn 2384-9568 doi: 10.23738/ccsj.i62016.04 1. introduction some hundred humorous illustrations concerning office work and published in italy in national periodicals and specific books were firstly collected. these images were analysed by the research group through frequency analysis in order identify the most recurrent work themes. the next step was to extract three illustrations to be used for the study, which involved adding experimental colorations. a total of twelve experimental boards were thus arranged – three in black and white, three with “reassuring and playful” colorations, three with “alarming and serious” hues, and three with mixed or ambiguous colourings. these last are useful for comparison because they may generate intermediate effects. we should focus on contrasting groups of physiognomic properties placed in a configuration and on colours. these properties are those corresponding to adjectives like “reassuring”, “relaxing” and “protective” or, on the contrary, “alarming”, “worrying” and “threatening”. these adjectives are part of the group of terms that metzger [1] called “valences” or “bridging qualities”, taken to mean the quality of the relationship between the phenomenal ego and objects, events, persons or environments. moreover, meanings such as “playful”, “cheerful” or, on the contrary, “serious” or “sad”, belong to the category of emotional tonalities, for which configurations – and colours – appear to bring out coexisting feelings and emotions [2]. in addition, the terms “playful” and “serious” have common nuances with the area of intentional qualities in the sense that the corresponding images bring out apparent intentions. studies on this topic have been carried out by hippius [3] and especially by arnheim [4]; as well as by others. in relation to this, in the 1970s we set up a new test in order to evaluate expressive sensibility. the test was called “linear forms and coloured bands” by bonaiuto, [5], and consisted of 50 black-and-white boards and 50 full-colour boards concerning the relations between positive, neutral or “negative” affective meanings. after the early 1980s, experiments were carried out in rome on perceptual defence or facilitation processes triggered by using models of incongruent and paradoxical buildings, connected to simultaneous verbal or non-verbal messages that were either of the stressing or relaxing kind [6]. 2. hypothesis and procedure the hypothesis envisaged that the “alarming and serious” colorations would trigger certain perceptual defence mechanisms in the person, such to inhibit the humorous experience. the “reassuring and playful” hues would instead give rise to an effect of facilitating humour, for which the average scores obtained would be significantly higher compared to those of the other versions. we shall now describe the chosen illustrations. the first illustration (figure 1) shows a business meeting in which seven employees are sitting at the table and looking towards the manager, who is standing up and has extracted a note from the suggestion box at the end of the table; he says, “here is a really excellent one: it’s mine!” the figure 1 (on the left) the “black and white” board figure 2 – (on the right) the board with “alarming and serious” hues figure 3 (on the left) the board with “reassuring and playful” colorations figure 4 – (on the right) the board with “mixed or ambiguous” colourings. 49 cultura e scienza del colore color culture and science | 06 | 2016 | 47 52 emotional qualities of colours added to humorous illustrations issn 2384-9568 figure 5 (on the left) the “black and white” board figure 6 – (on the right) the board with “alarming and serious” hues scene contradicts the common expectation that in a meeting people have to discuss things in order to arrive at a joint decision. paradoxically, the meeting seems to be a pure formality: any suggestions made by the seven employees of the meeting are not taken into consideration at all. here are the four chromatic versions of this first board which we have called “suggestions” (figure 2-4). the second board (figure 5) shows five employees sitting at a meeting table. standing up at one end is the manager with a smoking pistol in his hand. one of the employees is slumped on the table and the manager says, “is there anybody else here who does not approve my idea?” the scene contradicts the normal expectation that a business meeting does not envisage physical violence. here are the four chromatic versions of this second board, which we have called “shot” (figure 6-8). the third board (figure 9) shows two people sitting on a park bench. the one on the right is smartly dressed while the one on the left has tattered clothes and a broken hat. the latter says,“… and so, when the manager said ‘correct me if i’m wrong’, i corrected him. that’s why i’m here”. the scene contradicts the expectation that a good natured conversation cannot have tragic figure 7 (on the left) the board with “reassuring and playful” hues figure 8 – (on the right) the board with “mixed or ambiguous” hues 50 cultura e scienza del colore color culture and science | 06 | 2016 | 47 52 biasi v. and bonaiuto p. issn 2384-9568 doi: 10.23738/ccsj.i62016.04 consequences. here are the four chromatic versions of this third board, which we have called “bench” (figure 10-12). the twelve tables were individually evaluated one at a time by a group of 116 adult participants of both genders (58 males and 58 females), figure 9 the “black and white” board figure 10 the board with “alarming and serious” hues figure 11 the board with “reassuring and playful” colorations figure 12 the board with “mixed or ambiguous” colourings 51 cultura e scienza del colore color culture and science | 06 | 2016 | 47 52 emotional qualities of colours added to humorous illustrations issn 2384-9568 aged 18-50 years. each participant evaluated each illustration in the different versions and colorations. the coloured boards were presented randomly after the black and white version. for each image, the participant gave a humour score on an 11-step scale from 0 (minimum level of humour) to 10 (maximum) (figure 13). for statistical analysis, the means, standard deviations (s.d.) and student t test were calculated for each situation. 3. results the results appear to confirm the research hypothesis. the mean humour scores vary as expected: systematically, the “alarming and serious” versions obtained lower humour scores compared to the “reassuring and playful” versions, thereby confirming the aforesaid hypothesis. there were no significant gender differences. here are the tables with the quantitative results obtained (tables 1, 2 and 3). there is a strong significant inhibiting influence of the “alarming and serious” colorations compared to the “reassuring and playful” ones for all the boards: “suggestion” (t 115= 9.36; p<0.001); “shot” (t 115= 12.37; p<0.001) and “bench” figure 13 reproduction of the self-evaluation scale for assessing humorous experience, from 0 (minimum) to 10 (maximum) (t 115= 2.25; p<0.02). the “alarming and serious” boards appear to significantly inhibit humour also in comparison with the black and white boards: “suggestion” (t 115= 4.84; p<0.001); “shot” (t 115= 7.74; p<0.001); “bench” (t 115= 2.92 ; p<0.01). the mean humour scores in the humorous illustrations with “reassuring and playful” colorations are significantly higher than those of the black and white version with regard to the boards “suggestion” (t 115= 4.86; p<0.001) and “shot” (t 115= 6.53; p<0.001). finally, there were no differences in mean humour scores between the black and white versions and mixed versions; the only significant difference was found in the board entitled “suggestion” (t 115= 3.81; p<0.001). 4. comments and conclusions the experimental study confirmed the starting hypothesis, demonstrating that the colorations with a strong emotional valence can significantly influence humour perception. two main ranges of hues were recognised: one which includes colorations defined as “reassuring and playful”, consisting of colours such as pink, orange, light green, pale yellow, sky blue and other pastel hues; while a second range defined as “alarming and serious” includes such colours as black, grey, olive green, purple, dark blue and possible red and yellow stripes [5] [7] [8]. it was hypothesised and then statistically confirmed that this influence moves in two opposite directions: “reassuring and playful” colorations have a “facilitating” effect on humour perception, i.e., they favour humorous experience. the “alarming and serious” colorations instead have an opposite effect on humour because they tend to hinder and inhibit humorous experience. in line with the reference contributions and with the working hypothesis that guided the research, we could thus confirm that the humorous effect is significantly greater when the illustrations are presented in the “reassuring and playful” colour versions rather than in the “alarming and serious” ones. this hypothesis was precisely confirmed in all three cases examined in the study by systematically obtaining higher means for humour with the “reassuring and playful” colorations in comparison with the “alarming and serious” ones. the mixed (or ambiguous) hues coherently gave rise to intermediate scores. this shift in humorous experience can be explained in terms of an increase or decrease in emotional conflict experienced by the ordinary beholder: the “reassuring and playful” colorations trigger positive emotions in the beholder and enable the feeling of reassurance which in average scores s.d. allarming and serious version 4.41 2.00 reassuring and playful version 5.75 2.23 mixed version 5.64 2.07 black and white version 5.16 2.48 table 1 mean scores and standard deviations of the 116 participants with regard to the board “suggestion” average scores s.d. allarming and serious version 4.74 2.17 reassuring and playful version 6.50 2.40 mixed version 5.83 2.21 black and white version 5.87 2.36 table 2 mean scores and standard deviations of the 116 participants with regard to the board “shot” average scores s.d. allarming and serious version 4.66 2.15 reassuring and playful version 5.00 2.09 mixed version 5.18 1.99 black and white version 5.09 2.44 table 3 mean scores and standard deviations of the 116 participants with regard to the board “bench” 52 cultura e scienza del colore color culture and science | 06 | 2016 | 47 52 biasi v. and bonaiuto p. issn 2384-9568 doi: 10.23738/ccsj.i62016.04 turn facilitates emotional detachment; these necessary components particularly facilitate humorous experience. on the other hand, “alarming and serious” colorations trigger negative emotions which stimulate the onset of psychic defences on the part of the beholder. these defence mechanisms increase conflict and therefore inhibit humorous experience. as explained in detail in the theoretical model by bonaiuto and giannini [9] cf. also bonaiuto [10]; biasi, bonaiuto and levin [11] [12], humour springs from the perception of an anomaly or a paradox, that is, something which strongly contradicts the beholder’s expectations. faced with such incongruent and bizarre images, the individual manages to smile and experience humour thanks to certain psychological ingredients. the main ones are emotional detachment with regard to the observed incongruity, and thus experiencing feelings of reassurance and protection, and feelings of superiority, which all enable the beholder to reprocess in a comic and humorous manner what is initially perceived as conflictual. this role of humour as a defence mechanism in the face of conflictual and partly frustrating situations has been amply dealt with by various authors, starting with freud [13], and has been recently discussed with experimental demonstrations by bartoli and bonaiuto [14] and by biasi [15]. funding this research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. conflict of interest i disclose any actual or potential conflicts of interest including financial, personal or other relationships with other people or organizations within three years of beginning the submitted work that could inappropriately influence, or be perceived to influence, the work. i declare explicitly that potential conflicts don’t exist. note dr. sara longo helped in finding original humorous illustrations in black and white and some of the participants of the experiment. bibliography [1] w. metzger, “psychologie”, steinkopf, darmstad, 1954. [2] p. lersch, “gesicht und seele. grundlineen einer minischen diagnostik”. munchen: reinhardt, 1931. [3] m.t. hippius, “graphischer ausdruct von gefuhlen”, zeitscrift für angewandte psychologie und charakterkunde, 51 (5-6), 257-336, 1936. [4] r. arnheim, the gestalt theory of expression. psychological review, 56, 156-171, 1949. [5] p. bonaiuto, “forme lineari e bande colorate. un reattivo per la valutazione delle capacità di percepire l’espressività visuale”, eur, rome, 1978. [6] a.m., giannini, v. biasi, p. bonaiuto, “un nuovo esperimento sui processi percettivi di attenuazione o risalto di anomalie strutturali, influenzati dal colore”, comunicazioni scient. psicologia generale, 13, 101-132, 1995. [7] v. biasi, p. bonaiuto, “the graphic-pictorial language of stress (conflict) and comfort (agreement) in fairy tale illustrations”. in h. gottesdiener & j.c. vilatte (eds), culture and communication, iaea, pp. 473-477, avignon, 2006. [8] v. biasi, p. bonaiuto, a.m. giannini, “emotional qualities and valences of colours: a review of experimental demonstrations”. in a. rizzi (ed.), colore e colorimetria: contributi multidisciplinari vol. iii, centro editoriale toscano, pp. 183-194, florence, 2007. [9] p. bonaiuto, a.m. giannini (eds), “selezione di contributi in tema di psicologia dello humour”, e.u.r, rome, 2003. [10] p. bonaiuto, “art, science and humour. the study of humorous experience at the intersection between psychology and the art world”, empirical studies of the arts, 24 (1, special issue), 3-41, 2006. [11] v. biasi, p. bonaiuto, j.m. levin. “the ‘colour family drawing test’: a comparison between children of ‘harmonious’ or ‘very conflictual families’”. psychology, 5, 2099-2108, 2014. http://dx.doi.org/10.4236/ psych.2014.519212 [12] v. biasi, p. bonaiuto, j.m. levin. “the “colour family drawing test”: assessing children’s perception of family relationships. studies on mental health and crosscultural comparisons. health, 7, 300-307, 2015. http:// dx.doi.org/10.4236/health.2015.73034 [13] s. freud, “der witz und seine beziehung zum unbewußten”, deuticke, leipzig, 1905. [14] g. bartoli, p. bonaiuto, “psicodinamica e sperimentazione”, n.s.c./carocci, rome, 1997. [15] v. biasi. “il conflitto psichico. analisi fenomenologiche e verifiche sperimentali”, monolite, rome, 2006. [18] f. pierotti, “the colour turn: l’impatto digitale sul colore cinematografico”, bianco e nero, lxxv(580), 26–34, carocci, rome, sept.–dec. 2014. 74 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110109 semantic resonance to light sources of different correlated colour temperature pietro fiorentin 1 , osvaldo da pos 2 , elena pedrotti 1 , ariella metellini 3 1 department of industrial engineering, university of padua. pietro.fiorentin@unipd.it, pedrotti.e@gmail.com 2 department of general psychology, university of padua. osvaldo.dapos@unipd.it 3 national institute of nuclear physics, padua. ariella.metellini@pd.infn.it corresponding author: osvaldo da pos (osvaldo.dapos@unipd.it) abstract new light sources are nowadays used as a consequence of energy saving problems and developments of illumination technology. their quality is evaluated in terms of their rendering capabilities and of people preferences. the research is focused on the psychological reaction of young participants to the environmental lighting of three rooms expressed by subjective measures of a list of associable qualities. we then describe how observers can distinguish different qualities of interior lightings. one room was lighted by a halogen lamp, and two other rooms by led lamps. walls were white and a rather large coloured mondrian was hung at a wall. a group of 370 high school students volunteered in the experiment. their task was to evaluate the quality of the three illuminations by using a semantic differential. evaluations were performed in small groups or individually, and data were collected for each participant. many students left the experiment after performing their task in one or two rooms only. therefore, data from 197 students who completed the task in all the three rooms were considered. an anova shows that the halogen lamp receives evaluations significantly different from the other two light sources. the two leds received equal evaluations in seven scales and significantly different in other three scale. a factorial analysis identifies three factors; in relation to all of them the halogen lamp significantly differs from the leds, while the two leds differ one from the other only in two factors. in conclusion naive young participants can consistently evaluate personal psychological reactions to lights and discern the qualitative features of the lightings; evaluations are not consistent with the differences in cct of the three sources but seem affected by other lighting characteristics; some evaluations seem to depend on participants’ psychological context. keywords led, cct, lighting quality, psychological reaction, semantic differential received 15 september 2018; revised 10 june 2019; accepted 27 june 2019 citation: fiorentin, p., da pos, o., pedrotti, e., & metellini, a. (2019). semantic resonance to light sources of different correlated colour temperature. color culture and science journal, 11(1), 74–81. https://doi.org/10.23738/ccsj.110109 semantic resonance to light sources of different correlated colour temperature 75 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110109 1. introduction we are today aware that on the one side energy resources are limited, and on the other side energy production goes with more or less detrimental alterations of the environment. the actual and universal problem is then how to prevent environmental damages by reducing energy consumption without worsening machinery performances. in the specific case of light production, we face the challenge of maintaining good quality of artificial light by developing new technologies to spare electricity consumption. if technological problems are to be solved inside engineer frames of reference, evaluation of the light quality involves psychological disciplines since the final user is the human observer. research in the field of illumination covers a very wide spectrum of topics, roughly divided between physical factors and psychological effects, many times both. the subjective aspects of illumination, that is the psychological reactions to the different variables characterising both indoor and outdoor llighting, become more and more relevant because the final users are human persons. some research works are addressed to general aspects of environmental illumination (cie 212:2014; sansoni, mercatelli, farini 2015), other research deal with diffuse vs accent illumination or their interaction (tantanatewin, inkarojrit 2016), interactions between surface colour and illumination, illumination for different purposes (jin et.al. 2015), cct and cri (farini 2015). a critical item in many researches is the use of simulation (scenes projected in a screen, tantanatewin, inkarojrit 2016) vs real environment (a small room in jin et al. 2015). we are also conscious that various illumination devices differently affect colour appearance and the problem of evaluating the perceived quality of the light sources arises not only in terms of their rendering capabilities but also of people preferences (thornton 1974; yildirim et al. 2011). this research aims to describe how observers can distinguish different interior lightings in terms of their own peculiarities and of the psychological effects they generate in people. 2. the experiment the experiment was performed in the frame of the cultural event “experiencing: an interactive scientific exhibition energy and life”, held in padua in 2015, inside the series of annual events “experiencing” which started in 2002 to promote science in higher grade schools. 2.1. participants about 10000 students attended the one month event and about 370 students, nearly half male and half female, from 15 to 19 years old, agreed to be accompanied by a guide and take part in the experiment. they could perform the experiment either singularly or in small groups of 10 people on the average. as many participants left the experiment before judging the lightning of all the three rooms, only data from the 197 participants who completed the experiment were used in the analysis. 2.1. material the experiment was carried out in three small rooms (about 2 x 3 m) with white walls (figure 1); in each room a coloured mondrian (50 x 50 cm) was hanging on one of the longer wall and a computer with a crt monitor was placed on a small white shelf fastened horizontally on a short wall. the monitor was used to show the items of a semantic differential and record the participants’ answers. the luminaires were placed above the door facing the other short wall. three kind of light sources were installed, one halogen lamp, one medium cct (davis and ginther, 1990) led lamp, and one higher cct led lamp with the characteristics shown in table 1. as usual, halogen source presents a more diffuse light, while leds are a bit more directional, even if in any case the light direction is controlled either by a reflector or by lenses. this fact is highlighted by the lowest illuminance value for the haloghen source. in the entrance room a commercial viewing booth with different light sources was placed on a table; a large poster was hanging on the wall above and showed the main characteristics of the cabinet sources and the ways of measuring them by appropriate instruments. fig. 1. the rooms where the experiment has been performed. semantic resonance to light sources of different correlated colour temperature 76 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110109 room source watt cct cri lm lx on the wall efficiency 1 halogen 150 3000k 98 3000 about 400 21 lm/w 2 led-a 35 3080k 80 3100 about 500 89 lm/w 3 led-b 35 3890k 80 3230 about 600 92 lm/w tab. 1. specifications of the three light sources. the evaluations of the lights illuminating the rooms were performed by using 10 verbal semantic scales (cie 212: 2014; osgood et al. 1957; snider and osgood 1969). four scales were referring to the observer feelings: 1) calm – agitated; 2) relaxed – tense; 3) speedy – slow; 4) passive – active (original italian scales: calmo – agitato; rilassato teso; veloce lento; passivo attivo). the other six scales were referring to the characteristics of the light: 5) interesting boring; 6) strong – weak; 7) warm – cold; 8) desirable – undesirable; 9) brilliant – dull; 10) violent – soft (original italian scales: interessante – noiosa; forte – debole; calda fredda; desiderabile – indesiderabile; brillante smorta; violenta – gentile). the items were presented in the monitor screen with an invitation to save the subjective evaluations. participants could move a slider in the position between the two extremes which expressed their choice in the scale continuum; their decision was therefore based only on the visual appreciation of the two distances of the slider from the extremes (figure 2). later that position was decoded as a measure of the distance from the two extremes (in the example the slider shows a choice of 80% calm vs 20% agitated). fig. 2. the display used to register the participants’ evaluations of the semantic differential. 2.3. procedure first, participants were led to the entrance of the experimental place and shown different kinds of illumination inside a viewing booth. then the guide taught them about the main features of those light sources, like the physics of the production of the light, the measure of its power in watt, its luminous flux in lumen, its correlated colour temperature in kelvin, and its luminous efficiency. lastly participants were instructed about their task which was to give a subjective evaluation of the quality of three different lights in three rooms, and that this evaluations would be structured in a series of bipolar scales of adjectives referring both to the quality of the light and to the feelings they would experience under that light. their answer had to be expressed by appropriately using the mouse. the three rooms were visited in random order and at the end they could leave their email address to receive the results of the research. 3. results 3.1. analysis of variance the three room illuminations (figure 3) were globally judged significantly different (f2,392 = 93,14, p < 0.00001). specifically, the halogen illumination was judged significantly different from the led-a (p < 0.00001) and from the led-b (p < 0.00001), while the led-a source did not appear significantly different from the led-b source (p > 0.421). of course, the scales were evaluated in a significantly very different way (f9,1764 = 18.53, p < 0.00001), but there was an important interaction between scales and sources (f18,3528 = 101,09 p < 0.00001), which is of great interest for the purpose of the experiment. fig. 3. global evaluation of the three illuminations. semantic resonance to light sources of different correlated colour temperature 77 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110109 fig. 4. mean evaluations given by the participants to the semantic scales as a function of the three light sources. blue circles: halogen lamp; green triangles: led-a; red squares: led-b. fig. 5. mean evaluations of the subjective effects elicited by the different light sources on the observers. error bars = confidence intervals (mostly hidden by symbols). stars = significantly different ( < 0.05). an overall view of the interactions between lights and semantic scales is presented in figure 4, where the halogen light is connoted in a very different way from the other two led sources, which on the other side show some differences one from the other. an analytical presentation of the results relative to the single scales is following to show how participants exhibit different reactions as a function of the different light sources. figure 5 shows the results of an analysis of variance (anova) relative to the psychological effects induced by the tested lights as they were evaluated by the participants. the data are derived from the answers to the question “how does this light make you feel?”. from the results it appears that the halogen illumination is perceived as inducing a state of more serenity (p < 0.00001), calmness (p < 0.00001), relax (p < 0.00001), passivity (p < 0.00001) in opposition to the led lights which are judged to elicit tension, excitement, swiftness, dynamism. on the other side both led lights are similar in these psychological effects. semantic resonance to light sources of different correlated colour temperature 78 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110109 fig. 6. mean evaluations given by participants relative to the characteristics of the different light sources. error bars = uncertainty intervals (mostly hidden by symbols). stars = significantly different ( < 0.05). braket= the significantly different pair. these results are in agreement with what can be expected in relation to the halogen light source, whose rather warm light is largely preferred by most people in interior environments, where it gives an intimate atmosphere, and favour convivial, comfortable, tender interpersonal relationships. the association with candle lights, flames in the fireplace, or sunset light is based on the similar psychological effects they initiate. on the other side cool light as that often emitted by leds is generally considered unfriendly, although stimulating and speeding up, and therefore considered positive in specific circumstances. it is worth to note, even if cct is a very important factor in driving people feeling, it is not the only cause. there are other factors to consider also in our experiment, one of them is the uniformity of the light. differences between the results related to the considered sources can be partially associated also to the more uniform and soft lighting provided by the halogen source, with respect to leds. figure 6 shows the results relative to the qualities which participants ascribed to the different lights. the data are derived from the answers to the question “how do you estimate this light?” followed by the corresponding semantic scales again the halogen illumination is perceived quite differently from the other led illuminations, but at their turn these are not always judged in the same way. the halogen illumination always appears significantly less interesting (p < 0.00001), weaker (p < 0.00001), warmer (p < 0.00001), less desirable (p < 0.00001), duller (p < 0.00001) and softer (p < 0.00001) than the other led lights. the led lights moreover significantly differ one from the other in interest (p < 0.00001) being the led-a (3080k) more interesting than led-b (3890k), in temperature (p < 0.00001) with the led-a (3080k) warmer than led-b (3890k), and in violence (p < 0.044) with the led-b (3890k) more violent than led-a (3080k). as before, results relative to the halogen source are in agreement with the common consideration of appearing warmer (p < 0.00001), weaker (p < 0.00001), and softer (p < 0.00001). on the other side the interesting (p < 0.00001) appearance of the led light may be justified in this context where young people are visiting a science exposition of their works, and therefore feel rather excited and inclined to arousing lights. worth of note the halogen light is only considered more desirable than the led-b semantic resonance to light sources of different correlated colour temperature 79 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110109 (p < 0.001), and the led-b appears significantly less interesting than the halogen (p < 0.00001), but cooler ((p < 0.00001) and more violent (p < 0.044) than the led-a. 3.2. factorial analysis a more synthetic view of the results is given by a factorial analysis, which has been performed on the row data. the principal component analysis, with varimax rotation and kaiser normalisation, was carried out on the raw data, and the resulting factor loadings (cumulative variance = 73. 3) are shown in table 2. scales c1 c2 c3 active-,658 -,402 -,306 boring-,049 ,878 ,208 slow,595 ,518 ,102 weak,573 ,649 -,143 tense-,745 -,108 ,280 agitated-,652 -,436 ,325 warm,853 ,014 ,037 desirable-,103 ,108 ,920 brilliant-,410 -,749 ,043 soft,769 ,308 -,200 tab. 2. the factor loadings of the three principal components of the factorial analysis. the three factors, shown in table 3, can be interpreted as: 1“arousal”; 2“vivacity”; 3“evaluation” based on the semantic scales which characterise each factor. tab. 3. the semantic scale characterising the three factors. the factorial structure seems quite coherent and wellfitting the characteristics of the lights as emerged in the previous analysis of variance. an arousal factor is quite common in this kind of research, with the peculiarity of including together the osgood’s [3,4] activity and potency factors which often are separate. moreover this factor includes semantic scales related to both the subjective psychological effects (relaxed – tense; calm – agitated; passive – active; slow – speedy) and the qualities attributed to the lights (cold – warm; violent – peaceful). the vivacity factor includes only scales which deal with the qualities of the lights (strong – weak; brilliant – dull; interesting – boring). the evaluation factor, which concerns the positivity of the light, is saturated by one scale only (desirable – undesirable) which again is related to the quality of the light. an analysis of variance on original data weighted by the factorial coefficients has been performed to see how participants judged each illumination on the basis of the criteria expressed by the three factors, and the results are plotted in figure 7. fig. 7. factorial scores relative to each factor plotted as a function of the rooms’ illumination. factor 1 arousal factor 2 vivacity factor 3 evaluation cold warm violent soft tense relaxed active passive agitated calm speedy slow speedy slow interesting boring brilliant dull strong weak strong weak desirable undesirable semantic resonance to light sources of different correlated colour temperature 80 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110109 all three illuminations appear significantly different one from the other when judged on the basis of factor 1, that is their arousal power evaluated by participants is different (p < 0.00001 in all the three cases); moreover the halogen lamp receives much lower evaluations in absolute value than the other two led lights. when the lights are evaluated on the basis of factor 2 the halogen light appears connoted significantly less vivid than the led-a (p < 0.00001) but not the led-b light (p < 0.44), and the absolute values of the three evaluations are very close. lastly on the basis of factor 3 the halogen light is significantly different from both the led-a (p < 0.0023) and the led-b (p < 0.00001), with its absolute value much lower, while the led-a and led-b do not significantly differ, in agreement with the anova results. 4. conclusions noteworthy is that the students are for the first time performing the task requested by the experiment, nevertheless they show great discriminative ability, and also a great consistency. in fact, the dispersion of the results is quite low (in the displayed diagrams confidence intervals are most often smaller than the size of the symbols), thus favoring a good statistical significance. the results demonstrate a clear ability of participants who are able: 1) to recognize and evaluate different personal, psychological reactions to lights; 2) to estimate different qualitative characteristics of the light sources. the research aimed to highlight how young naive people perceive, discriminate, and judge indoor illuminations produced by different light sources. the attention was focused on the halogen and led sources, because of the large difference in their spectral power distribution, and the widespread impression that the incandescent sources like the halogen ones are presently preferred by most people. the first result that emerges is that the three lights are well distinguishable, especially the first vs the other two. despite both the halogen and the led-a sources have an almost indistinguishable colour temperature (cct 3000k-3080k), the two illuminations are always significantly discriminated on all semantic scales, with consideraby different absolute values. obviously, the same discrimination also takes place between the first and the third illumination, justified by the fact that the sources differ both in type and in the corresponding colour temperature, although not by much (cct 3000k vs 3890k). the second and the third lighting are not confused, even if the sources are of the same type (led) and of different, although small, correlated colour temperature (cct 3080k vs. 3890k): the discrimination, however, occurs only on some semantic scales: interesting-boring, warm-cold, violent-soft. this result challenges the relevance of the cct in connoting the relevant characteristics of a light source as some subjective characteristics seem to be quite independent from cct. some significant quality of the light described by the spectral power distribution (spd) is probably lost when the cct is considered. this research has not investigated the colour rendering properties of the light sources. nevertheless, the concept of colour rendering was presented and the cri (colour rendering index, cie 13.3: 1995) of each source was analysed in the introductory step of the experiment. moreover, participants were shown three mondrian (one per room) with the same colours but in a different spatially organized way (always random, anyway) in order to compare the possible colour differences caused by different sources, even if unconsciously. these overall results agree quite well with the general impression that people have without scientific investigations, and the advantage of the experimentation is to supply a scientific confirmation the current conceptions, and to highlight unexpected aspects. in our case the desirability appears to be low for the light that gives calm, and high for that exciting: the hypothesis is that the situation makes desirable a light with characteristics appropriate to the circumstances. in particular, students who go together to see a show of scientific experiments, perhaps having presented their well accepted works, are not in a state of tranquillity, but rather activated, and therefore prefer an arousing lighting like that produced by leds, especially if in those moments they are sensation seeking. it is very likely that in other circumstances the desirability goes calming lights. to be verified. conflict of interest declaration the authors disclose any actual or potential conflicts of interest including financial, personal or other relationships with other people or organizations within three years of beginning the submitted work that could inappropriately influence, or be perceived to influence, their work. the authors state that financial/personal interest have not affected their objectivity. the authors state explicitly that potential conflicts don’t exist. funding source declaration semantic resonance to light sources of different correlated colour temperature 81 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110109 this research did not receive any specific grant from funding agencies in the public, commercial, or not-forprofit sectors. short biography pietro fiorentin is associated professor of “electrical measurements” and “light engineering and photometry” at the university of padova. he is responsible of the photometric laboratory dealing with external and internal lighting, with particular care to the colour rendering. he studies also the effect of artificial lighting on the night sky luminance, phenomenon known as “light pollution”. osvaldo da pos is senior scholar at the university of padua. graduated in biology, taught physiological psychology, general psychology, psychology of perception (for the degree in psychology), and at the psychology doctorate course. co-founder of the interdepartmental centre of colour and art, former national representative at cie and aic. his main research interest is in the field of colour pschology, especially in colour and illumination perception. elena pedrotti was born in 1980. graduated in electrical engineering in 2005 and phd in 2010 from the university of padua. she works as lighting designer by planning of lighting facilities for indoor or outdoor work places and is worked occasionally with the laboratory of photometry and lighting of the department of electrical engineering of the university of padua. ariella metellini was born near by treviso (i) in 1945. she got a degree in physics at padova university in 1970. from 1970 up to 2001 she had a stable position as a teacher of mathematics and phisics in un agronomical school. after retirement, at the end of 2001, she was responsible of the scientific interactive show "sperimentando" that is now at the 18th edition. references cie 13.3: 1995, ‘method of measuring and specifying colour rendering properties of light sources (e)’. isbn: 978 3 900734 57 2 cie 212:2014, ‘guidance towards best practice in psychophysical procedures used when measuring relative spatial brightness’. isbn 978-3-902842-51-0 davis, r.g. and ginther d.n. (1990) ‘correlated color temperature, illuminance level, and the kruithof curve’, journal of the illuminating engineering society, 9, 27:38. doi: 10.1080/00994480.1990.10747937 farini, a. (2015). color rendering of light sources. in sustainable indoor lighting (pp. 77-85). springer, london. jin, c., noguchi, h., qiu, j., wang, h., sun, y., & lin, y. (2015, november). the effect of color light combination on preference for living room. in solid state lighting (sslchina), 2015 12th china international forum on (pp. 139-142). ieee. sansoni, p., mercatelli, l., & farini, a. (2015). sustainable indoor lighting. london: springer. osgood, c.e., suci, g., tannenbaum, p. (1957). the measurement of meaning. urbana: il: university of illinois press. snider, j.g., osgood, c.e. (1969) semantic differential technique: a sourcebook. chicago: aldine. tantanatewin, w., & inkarojrit, v. (2016). effects of color and lighting on retail impression and identity. journal of environmental psychology, 46, 197-205. thornton wa (1974) a validation of the color-preference index. journal of the illumination engineering society 4:48–52 yildirim, k., hidayetoglu, m. l., & capanoglu, a. (2011). effects of interior colors on mood and preference: comparisons of two living rooms. perceptual and motor skills, 112(2), 1-16 color culture and science cultura e scienza del colore ccsj volume 14 number 2 2022 issn 2384-9568 color culture and science journal cultura e scienza del colore ccsj jcolore.gruppodelcolore.it issn 2384-9568 doi: 10.23738/ccsj.00 ance: e227716 registrazione tribunale di milano n. 233: 24/06/2014 anvur agenzia nazionale valutazione sistema universitario e ricerca apej academic publications ejournal base bielefeld academic search engine dbh database for statistikk om høyere utdanning doaj directory of open access journals ezb elektronische zeitschriftenbibliothek regensburg jurn search tool for open access content road directory of open access scholarly resources volume 14, number 2, october 2022 doi 10.23738/ccsj.140200 publisher gruppo del colore – associazione italiana colore www.gruppodelcolore.org registered office: piazza carlo caneva, 4 20154 milan (it) peer review process all articles submitted to the color culture and science journal are peer-reviewed according to the following procedure: first review level the associate editors evaluate each article to determine if the topic and content are of interest to the journal. once the article passes the initial review, the associate editors select several reviewers from the editorial board based on their expertise in a particular subject area or topic. second review level two or three experts review each article with a blind peer-review process where the reviewers are kept anonymous. reviewers are asked to evaluate the manuscript based on the following criteria:  originality  relevance to journal's aims and scope  technical merit and/or validity  soundness of methodology  completeness of the reported work  conclusions supported by the data  correct acknowledgment of the work of others through reference  effectiveness of the manuscript (organization and writing)  clarity of tables, graphs, and illustrations  importance to color researchers  relevance to color practices if the article is accepted with major revisions, the author(s) are asked to improve the article according to the reviewers' suggestions. the revised article will then be submitted for further review. after collecting the reviewers' reports, the associate editors recommend the acceptability of the article to the editor-in-chief. editor-in-chief maurizio rossi (politecnico di milano, it) deputy editor alice plutino (università degli studi di milano, it) associate editors josé luis caivano (universidad de buenos aires, ar) vien cheung (university of leeds, uk) marco gaiani (alma mater studiorum università di bologna, it) robert hirschler (serviço nacional de aprendizagem industrial, br) agata kwiatkowska-lubańska (academy of fine arts, kraków, pl) marcello picollo (ifac-cnr, it) verena m. schindler (chair aic s.g. environmental colour design, ch) renzo shamey (nc state university, usa) editorial board members the complete and updated list of the editorial board members involved in the peer review process is available on the ccsj website: http://jcolore.gruppodelcolore.it/ojs/index.php/ccsj/about/editorialteam topics the ccsj accept papers on a wide range of topics on color, including and not limited to the following: 1. color and measurement/instrumentation. colorimetry, photometry and color atlas: method, theory and instrumentation; quality control and food coloring, dyes, organic and sustainable color. 2. color and digital. reproduction, management, digital color correction, image processing, graphics, photography, film and video production, printmaking and 3d print, artificial vision, virtual reality, multispectral imaging, data visualization. light field imaging. multi-sensor fusion. color localization, recognition, hdr imaging, adas systems. 3. color and lighting. metamerism, color rendering, adaptation, color constancy, appearance, illusions, color memory and perception, color in extra-atmospheric environments, lighting design, lighting technologies, visual comfort. 4. color and physiology. mechanisms of vision in their experimental and theoretical aspects, color vision and color appearance, deficiencies, abnormalities, clinical and biological aspects, synesthesia, health, well-being. 5. color and psychology. phenomenology of colors, color harmonies, color & form, perceptive, emotional, aesthetic, and diagnostic aspects. 6. color and production. food and beverages, agriculture, textiles, plastic materials, ceramics, paints, gemology, color in the food industry. 7. color and restoration. archaeometry, painting materials, diagnostics, and conservation techniques, restoration, and enhancement of cultural heritage. 8. color and environment. representation and drawing, urban planning, the project of color, architecture, interior design, landscapes & horticulture, color and architectural syntax, territorial identities, biodiversity. 9. color and design. furniture, cmf design, fashion, textiles, textures, cosmetics, food design, museography. 10. color and culture. arts and crafts, history, philosophy, aesthetics, ethno-anthropology, graffiti, geology, sociology, lexicology, semantics, anthropology of vision, food culture and heritage, color naming. 11. color and education. pedagogy, didactics of color, aesthetic education, artistic education. 12. color and communication/marketing. graphics, communication, packaging, lettering, exposure, advertising. http://jcolore.gruppodelcolore.it/ojs/index.php/ccsj/about/editorialteam 3 color culture and science journal vol. 14 (2) issn 2384-9568 table of contents editorial 5 alice plutino, maurizio rossi colours, light and well-being: characterizeation of chromatic phenomena in collective housing 7 lorrain caumon, estelle guerry, georges zissis, céline caumon, elodie becheras, christelle infantes doi: 10.23738/ccsj.140201 colours of emotion, trust, and exclusivity: a cross-cultural study 14 peter broeder doi: 10.23738/ccsj.140202 pixar’s colorscripts: chromatic analyses of four films using sens|org|int model 22 paula csillag, amanda sabao doi: 10.23738/ccsj.140203 integrating knowledge about color within the stem/steam approach: some instructional procedural principles 28 berta martini, rossella d’ugo, monica tombolato doi: 10.23738/ccsj.140204 digital applications to train color ordering in three dimensions for architects and designers 38 juan serra, javier cortina maruenda, ana torres barchino, jorge llopis doi: 10.23738/ccsj.140205 more than a tube of color the emotion 45 lupe voss, sherman wong doi: 10.23738/ccsj.140206 4 color culture and science journal vol. 14 (2) issn 2384-9568 5 color culture and science journal vol. 14 (2) issn 2384-9568 editorial "the dog days are over the dog days are done can you hear the horses? 'cause here they come" [florence + the machines] dear readers, after different years of contributing to color culture and science journal (ccsj) as an author, i am proud to write this editorial as deputy editor together with the editor-in-chief. in recent years we assisted in the development, growth and resilience of the associazione italiana colore and this journal. in 2020 they organized the first online conference of the association, and in 2021 the association was able to organize, manage and handle the aic international 14 th congress, creating an event which connected people all over the world. in the same year, a new international conference was proposed, the "colour photography and film: sharing knowledge of analysis, preservation, conservation, migration of analogue and digital materials", held online in 2021, and in person in 2022, in its second edition. after so much work online, this year it has been a pleasure to meet all the colour experts, professionals, academics and passionate again in person during the "xvii color conference" in september. during the pandemic, the associazione italiana colore did not stop, but found new energy to develop, improve and complete regular and extraordinary tasks. and i am so glad to become part of this organization. this editorial is dedicated to all the volunteers supporting the associazione italiana colore, from the inside and outside. i want to thank all the backbones of this group, who contributed to building a stable and robust community, able to face all the encountered difficulties, and all the volunteers managing the website, the secretary, the promotion and the online environments during the conferences. an enormous thank you to the members who are no longer with us, who set the basement to the foundation of the associazione italiana colore. now that "the dog days are over", we are ready to restart full of energies, new ideas and projects to improve the associazione italiana colore and color culture and science journal. we invite you to publish and promote our journal, which is a blind, peer-reviewed, diamond open access, free for readers and authors. alice plutino dipartimento di informatica, università degli studi di milano maurizio rossi dipartimento di design, politecnico di milano 6 color culture and science journal vol. 14 (2) issn 2384-9568 cultura e scienza del colore color culture and science 78 cultura e scienza del colore color culture and science | 07 | 2017 | pompas r. issn 2384-9568 renata pompas michel pastoureau ha presentato, come aveva promesso, il quarto libro della serie dedicata alla storia dei colori nella società occidentale: “rosso. storia di un colore” (pubblicato in italia da ponte alle grazie, € 32,00). il libro è nel consueto formato (cm. 23 x 23), ha 216 pagine a colori e, come sempre, è completato da una ricca iconografia che permette una lettura parallela al testo; la stampa è accurata e le belle immagini sono ad alta definizione. i quattro capitoli descrivono il colore rosso da diversi punti di vista. “colore primo” illustra le materie coloranti. “il colore preferito” e “un colore contestato” analizzano alcuni significati simbolici tra i più pregnanti, nei diversi secoli. “un colore rischioso?” riguarda invece l’uso sociale del rosso nella vita mondana e negli emblemi politici. il rosso è il primo colore a essere riconosciuto, nominato e ad avere una ricchissima simbologia. pastoureau è anzitutto uno storico (insegna alla “école pratique des hautes études en sciences sociales“ della sorbona) e come tale affronta le diverse problematiche collegate al colore rosso dal punto di vista sociale. dice infatti lo studioso che “le questioni relative al colore hanno un carattere strettamente culturale (perciò) ogni storia del colore deve essere prima di tutto un storia sociale (…) che evidenzi come in qualunque società per quanto riguarda il colore la funzione primaria è la tassonomia: classificare, accostare, contrapporre, gerarchizzare”. nel capitolo “colore primo. dalle origini alla fine dell’antichità” pastoureau descrive le materie coloranti, i loro usi civili e review michel pastoureau “rosso. storia di un colore” michel pastoureau presented, as he had promised, the fourth book of his series dedicated to the colour’s history in western society: “red. history of a color” (published in italy by ponte alle grazie. € 32,00). the book is in the usual format (cm. 23 x 23), with 216 colour ed pages and, as always, it is completed by a rich iconography, that allows a parallel reading of the text, the printing of it is accurate, the images are beautiful and on high-definition. the four chapters describe the red color from different points of view. “first colour” illustrates the dyestuffs. “the favourite colour” and “a challenged colour” analyse some symbolic meanings among the most meaningful. “a risky colour?” concerns its social use in the worldly life and in the political emblems. red is the first color to be recognized, named and to have a rich symbolism. pastoureau is first of all an historian (he teaches at the “école pratique des hautes études en sciences sociales” of the sorbonne) and as such he addresses the various issues related to the red colour, from the social point of view. in fact, the author writes that “the issues of color have a strictly cultural nature (so) every color history have to be, first and foremost, a social history (…), that shows how in any society the primary function of colour is the taxonomy: to classify, juxtapose, contrast, prioritize”. in the chapter “color first. from the beginning to the end of antiquity” pastoureau describes the dyestuffs, its civil and religious customs and their dyeing applications, accompanied them with curious anecdotes; among them the fun 79 cultura e scienza del colore color culture and science | 07 | 2017 | michel pastoureau “rosso. storia di un colore” issn 2384-9568 religiosi e le loro applicazioni tintorie, accompagnandole da curiosi aneddoti; tra questi la divertente caricatura teatrale del barbaro germanico: “un uomo “gigantesco, obeso, riccio, rubicondo e rosso di capelli”. nel capitolo ”il colore preferito. vixiv secolo” il rosso è analizzato nella simbologia cristiana, dove ricopre il ruolo di fuoco ora purificatore e ora distruttore, di preziosissimo sangue di gesù, ma anche di sangue dell’impurità femminile. un rosso che connota imperatori, re e feudatari. simbolo dell’amore, della gloria e della bellezza, ma anche della lussuria e del peccato. non poteva mancare il rosso nell’araldica, campo di studi in cui pastoureau è specialista. nel capitolo “un colore contestato. xiv-xvii secolo” l’autore mostra la condanna sociale del rosso in quanto colore dei quattro vizi capitali, marchio d’infamia di prostitute e di reietti, abolito nei colori liturgici dal protestantesimo. il capitolo “un colore rischioso? xviiixxi secolo” inaspettatamente si apre con la storia della moda e diffusione del rosa come colore sostanza e nome -, prosegue con la tossicità delle sostanze cosmetiche del passato e si conclude con il significato politico del rosso e la sua presenza negli emblemi e nelle bandiere. pastoureau conclude scrivendo che, pur non essendo più in testa alle preferenze dell’occidente è il colore che: “rimane insuperato sul piano simbolico”. un libro ricco e stimolante in cui spesso gli argomenti si sovrappongono e distribuiscono nei vari capitoli con intricati rimandi. theatrical caricature of the germanic barbarian, a man: “huge, obese, curly, with red-faced and red hair.” in the chapter “the favorite color. vixiv century” the red colour is analysed in christian symbolism, where he held the role of fire sometimes purifier and sometimes destroyer, of the precious blood of jesus, but also that of female impurity blood. red connotes also emperors, kings and feudal lords. it is the symbol of love, glory and beauty, but also of lust and sin. the presence of red in heraldry could not missed, the field of studies in which pastoureau is a specialist. in the chapter “a disputed color . xiv-xvii century” the author shows the social condemnation of the red, because of the color of the four deadly sins, stigmatization of prostitutes and outcasts, that was abolished in the liturgical colors of protestantism. the chapter “a risky color? xviiixxi century” unexpectedly opens with the history of fashion and circulation of a pink like color, substance and name -, it continues with the toxicity of cosmetic substances of the past and ends with the political significance of the red and its presence in emblems and flags. pastoureau concludes writing that, although no longer topped the preferences of the west society, it is the color that “remains unsurpassed on the symbolic level.” a rich and stimulating book, in which the topics are often overlapped and distributed in the various chapters, with intricate cross references. microsoft word 150110 76 color culture and science journal vol. 15 (1) doi: 10.23738/ccsj.150110 the promise of color in marketing: use, applications, tips and neuromarketing alessandro bortolotti1,2, loreta cannito2,3, stefano anzani1,2 and riccardo palumbo1,2 1department of neuroscience, imaging and clinical sciences, university gabriele d’annunzio chietipescara. alessandro.bortolotti@uinich.it, stefano.anzani@uinich.it, riccardo.palumbo@unich.it. 2center for advanced studies and technology (cast), university “g. d’annunzio” of chieti-pescara. 3department of psychology, university of campania, 81100 caserta, italy. loreta.cannito@unicampania.it corresponding author: alessandro bortolotti (alessandro.bortolotti@uinich.it) abstract in our daily lives, we are constantly exposed to many stimuli, some of which influence our behavior without full awareness. one of these stimuli is color. in particular, our purchasing decisions are guided by individual color preferences. color preferences influence various daily tasks. for example, people make decisions within 90 s of their first interaction with products, and approximately 60-90% of the evaluation of a product is based solely on its color properties. however, these types of behavior often escape consumer awareness, so marketing may need the help of neuroscience. thus, it is necessary to place color preferences at the center of marketing strategies. however, few attempts have been made to unify the literature on the contribution of different color characteristics and the role of consumer characteristics. this article reviews scholarly articles that focus on the use of color in marketing, identifying salient features and highlighting limitations. practical implications and future directions for this area of research are outlined, with a particular interest in neuromarketing. the results obtained will be useful for both basic research and companies that want to operate consciously in the use of color. keywords color, marketing, psychology, context received 02/12/22; revised 07/02/23; accepted 20/02/23 the promise of color in marketing: use, applications, tips and neuromarketing 77 color culture and science journal vol. 15 (1) doi: 10.23738/ccsj.150110 1.introduction it is now known that people make decisions within 90 s of their first interaction with a product. approximately 6290% of the evaluation is based on color alone (singh, 2006); some of these decisions are emotion-driven and, therefore, escape consumer awareness (alsharif et al., 2021). in this particular case, one needs neuromarketing techniques, defined as the application of neuroscientific methods to analyze and understand human behavior in relation to markets and marketing exchanges (lee et al., 2007). optimizing the use of color in marketing is of paramount importance today, and several techniques have been employed to more accurately investigate the influence of color on consumer choices (shaw & bagozzi, 2018). to date, defining the term "color," giving it a definition acceptable to all stakeholders, is a very difficult challenge. over time, color has been defined in a myriad of ways, and it is fair to say that no universal and definitive definition has yet emerged (kuehni, 2012). to fully define or understand the phenomenon of color, it is important to distinguish two characteristics: the first relates to the physical nature of the stimulus encountered and the second relates to the response of the individual encountering the color (hunt, 1978). in the latter case, color can be described as a perceptual phenomenon present in everyday life, capable of influencing mood and behavior based on the emotions it arouses (babin et al., 2003; yildirim et al., 2011). at this point, the study of color preferences is crucial for the vast majority of "social subjects" (plack & shick, 1974). for example, the influence of color on purchasing behavior has been extensively studied (bellizzi & hite 1992). most research to date has focused on psychophysical descriptions, thus trying to describe how we perceive a given color by explaining its preference through wavelengths (camgöz et al., 2002). in addition, the lack of scientific publications on the use of color in marketing is related to the fact that research and results in this field have retained the preservation of individual companies to gain an economic advantage over competitors (bellizzi & hite, 1992). more recently, several studies have sought to investigate individual differences in color preferences based on gender (wilms & oberfeld, 2018) and context (palmer & schloss, 2010). therefore, it is of paramount importance to know the color variables well, because in marketing, an inappropriate choice of product or packaging color can lead to strategic failure (czinkota & ricks, 1983), in which context and target culture play an important role (elliot & mayer, 2012). however, to date, there have been mixed results on the contribution of color preference in marketing. the objective of this paper is to review the available literature and classify items according to color and consumer characteristics used as independent variables, as well as according to the area of application (e.g., branding, packaging, etc.). the goal of this study is to show how consumer color preference is a key factor in marketing strategies, as we believe it is one of the most influential variables to be considered in this field, showing how in discussions such as marketing alone as a survey tool is not enough to identify all kinds of purchase decisions, which is because neuromarketing has often been discussed recently. 2.theoretical background on color preference in the past, studies on color preference, or theories derived from them, have been described as confusing and contradictory (mcmanus et al., 1981). one of the first theories on the argument was proposed by humphrey (1976) who claimed that color preferences derive from signals that colors transmit to organisms in nature and that their preferences come from signals that we define as "approaching" (for example, the colors of a flower attracting pollinating insects) or "avoiding" (for example, the colors of a poisonous toad that discourages predators) (humphrey, 1976). then, color preference is expressed through the mechanism of "natural selection". hurlbert and ling (2007) reinterpreted the theory proposed by humphrey (1976), adding that color preference is based on innate behavioral adaptations (hurlbert & ling, 2007). they proposed an "innatistic" theory, suggesting that color preference is related to the human visual system as weightings on cone-opponent neural responses arising from evolutionary selection. according to the authors, the color vision system was adapted to improve performance on an evolutionarily important behavioral task, specifically highlighting gender differences in color preference (ling et al., 2006). ou et al. (2004) proposed an account based on the relationship between color and emotions, which they defined as "feelings evoked by both colors or color combinations’ (ou et al., 2004). color emotions can be causally linked to color preferences if colors are preferred to the extent that the visualization of colored objects produces emotions (positive or negative) in the observer. the proposed theory considers gender differences in color preferences. the so-called ecological valence theory (evt) is a coherent and complete theory of human color preferences (palmer & schloss, 2010). evt incorporates previously cited theories but with some differences. consistent with humphrey ’s (1976) and hurlbert and ling’s (2007) ideas, evt is based on the premise that human color preferences are fundamentally adaptive. this ecological heuristic is adaptable to the concept of survival, where the color provides a good/bad index of a given object, which makes the survival of the individual the promise of color in marketing: use, applications, tips and neuromarketing 78 color culture and science journal vol. 15 (1) doi: 10.23738/ccsj.150110 easier. while hurlbert and ling ( 2007) refer to an evolutionary timescale (where genetic adaptations are inherited through generations), evt seeks to incorporate the proposed theories, extending the range of potentially adaptive mechanisms to include individual organisms learning color preferences on an ontogenetic timescale. evt also connects to emotion-based theory (ou et al., 2004) by showing how environmental feedback is necessary for learning-based heuristics, and that color preferences are provided by the emotional results of color-relevant experiences throughout a person's life. evt implies that the average preference for any color on a representative sample of people should be largely determined by their average effective responses to their corresponding colored objects. the more enjoyment and positive the effect that an individual receives from experiences with objects of a given color, the more the person will tend to appreciate that color. therefore, people should be attracted by colors associated with salient objects that generally elicit positive emotional reactions, and should reject colors associated with salient objects that generally elicit negative reactions. to date, although different theories have been proposed to explain human color preferences, as well as the impact of a specific color on individual preferences and choices, existing controversies in the literature prevent the efficient application of knowledge about color preferences in marketing strategies (schloss & palmer, 2011). the controversies in this field of studies are mainly due to the complexity of two aspects: the color and its properties on one hand (bortolotti et al., 2022; cohen, 2004) and the characteristics of the human being (schloss 2015), such as demographic differences (gender and age) and cultural differences, little considered until a few years ago, on the other hand (madden et al., 2000). as previous reviews have shown (labrecque et al., 2010), for a long time, studies in this field have focused only on color hue, excluding other physical characteristics such as lightness. as seen in another review paper (elliot, 2015), there are different difficulties and limitations in studies on color and psychological functioning, especially for the manipulation of color stimuli. the objective of this review is to demonstrate the importance of color research in marketing and consumer behavior, providing a new perspective by integrating previous theories regarding color preference. as a starting point, the extant literature is reviewed to generate a better understanding of how consumers perceive color and its influence on decisionmaking. given many processes and the number of characteristics related to color, it is not difficult to believe that there is a huge variance in the types of experimental protocols and variables considered. to better understand how to use color in marketing it is necessary to consider different variables, both individual and color-related characteristics; these variables must be considered because they significantly influence the preference for a given color. the variables that influence this process are described in detail below. 2.1.physiology of color perception the perceptual process involves the subjective processing of a stimulus; in short, color exists only in the mind; that is, it is a highly subjective experience that creates strong individual differences (helm & tucker, 1962). this can be described as a perceptive, highly subjective response to light entering the eye directly from self-luminous light sources, or indirectly from light reflected by illuminated objects (brainard & maloney, 2011). without going into too much detail, color vision requires the presence of at least two types of photoreceptors (cones and rods) with different spectral sensitivities; more precisely, cones, which are photoreceptors that distinguish in three categories, s (short) cones that are particularly sensitive to short wavelengths, m (medium) cones that are particularly sensitive to wavelength averages, and l (long) cones, sensitive to long wavelengths. each color can be described in terms of three main attributes: hue, saturation, and lightness (wong 2010). hue is identified as the color family or name of the color (e.g., red, green, purple), which is a measure of a color's purity or the intensity or weakness of the color, and lightness is the tint (darkness) or hue (clarity) of a perceived color (jagnow, 2010). the perceptual process, in all its complexities, influences affect, cognition, and behavior, but the reverse is also true; that is, affective, cognitive, and behavioral states can influence the perception of color (elliot & maier, 2012). 2.2. color and culture one of the variables that strongly influences the preference for a given color, also modulating the meanings it carries, is culture of reference (taylor et al., 2013). culture is the foundation of our lives and lifestyles. the behavior of human beings has a direct impact and reflects their cultural aspects of human beings. asian, middle eastern, european, and american cultures have rich values that make people living in those counties unique to each other. these cultures retain their beliefs and associations with colors to show the value of each culture individually, which makes the preference for color a culture-dependent factor and not a universal factor (taylor et al., 2013), although there may be some similarities (yokosawa et al., 2016). in some cultures, religion plays a significant role as a factor influencing culture (soma and saito 1997). it can be concluded that, the promise of color in marketing: use, applications, tips and neuromarketing 79 color culture and science journal vol. 15 (1) doi: 10.23738/ccsj.150110 currently, the use of color in marketing is not universal because of the individual variables underlying culture and color preference. to better understand the cultural "macro-category" we should study in detail other individual characteristics, such as age and gender because within the same culture there are individual differences related to color preference and make it a highly subjective process. 2.2 color and gender in marketing, attention must be paid to gender differences in preferences for certain colors. in this regard, several studies have been carried out that have found empirical evidence, albeit with some differences between them (silver et al., 1988; ellis & ficek, 2001). in this field, one of the first major discoveries was that females showed a greater preference for warm colors (red, pink, yellow, etc.) than males, and males showed a greater preference for cold colors (blue, green, etc.) than females (helson & lansford, 1970). more recent works by hurlbert and ling (2007) showed that females prefer reddish shades and do not like greenish-yellow tones significantly more than males do. these gender differences in shade preference could be explained by cultural differences (al-rasheed 2015). a very relevant study has obtained differences related to the gender of the participants in their experiment, but more importantly, note that they tried to identify differences in color preference in sexual orientation, and did not find significant differences between heterosexual and homosexual/bisexual of both sexes. in other words, homosexual/bisexual males and females essentially showed the same color preference configuration as their heterosexual counterparts. these studies support the idea of ling and hurlbert’s (2007) claim of a universal sex difference, which means that women universally prefer redder shades than the background. however, today, there is still a long way to define a universal color preference and apply it to marketing without damaging the company. 2.3 color and age contextual factors significantly influence older consumers’ decision-making ( yoon et al., 2009). in this field, different studies have confirmed a change in color preference during aging (gaines & little, 1975). different results suggest that color preference changes during adulthood (dittmar, 2001). these changes seem to be a reversal of the trend reported in literature for children. the change in color preference in the elderly could be attributed to alterations in color discrimination and visual images, yellowing of the lens, and decreased function of the blue cone mechanism with aging. other results. jain et al. (2010) showed that the color preference of an older person is different from that a of younger person. the determinants of color preference were the attributes of chroma and lightness in the older and younger groups, respectively. in this field of study, marketing strategies should be targeted at a specific age, given the difference in color preferences throughout life. 2.4 color and context in this case "context" means the entire space, place, and combination with which the color is associated. what is interesting in the field of marketing is how to use the color in the most "universal" way possible to obtain a purchase, as it is well known that when the same color is used in different contexts, the perception of that color can change radically. this aspect has been studied very carefully by psychologists, as in the case of the "theory of color in context" (elliot, 2015; elliot & maier, 2014), which is designed to be a broad model of color and psychological functioning that can be used to explain and predict the relationships between color, cognition, and behavior (elliot & maier, 2007). the theory of color in context is based on six main assumptions: (1) color has a meaning, (2) color vision influences psychological functioning, (3) color effects are automatic, (4) color meanings (and related responses) have two sources: learning and biology, (5) the relationship between perception and color influences cognition and behavior that are reciprocally interrelated, and (6) color meanings and effects are context-specific. this is the most accredited and comprehensive theory that can be applied to marketing. 2.5 color association color and its association with products act on human bodies, minds, and emotions, influence mood and feelings, trigger deep and subtle responses at the subconscious level of the consumer, trigger both topdown and bottom-up attention processes, influence thinking, stimulate action, and provoke reactions (park & smith, 1989). color can irritate or soothe, increase blood flow pressure or suppress appetite, and suppress appetite. it has been found that satisfying consumers' color expectations are beneficial to brand quality by increasing processing fluidity and facilitating product category identification (labrecque & milne, 2012). this creates color-product expectations in the consumer's mind, which i would dare to index as "congruent category" and "incongruous category". the colors in packaging can conform to the intuitive meaning that color has for a given product category. according to the theory of categorization, individuals tend to organize their external environment based on their previous experiences (knapp & anderson, 1984; rehder, 1986). that is, based on knowledge accumulated within a given conceptual domain, people form cognitive categories the promise of color in marketing: use, applications, tips and neuromarketing 80 color culture and science journal vol. 15 (1) doi: 10.23738/ccsj.150110 over time or sets of expectations, which are then used to determine how future experiences will be learned (sujan & bettman, 1989). 2.6 color in marketing as we now know, color preference is an automatic mechanism (kareklas et al., 2014), even if it is very complex to explain, especially when all the variables involved are taken into account, or more simply when several colors are used in opposition to each other (deng et al., 2010). colors and their use seem to be very controversial and certainly not universal (elliot, 2015; taylor et al., 2013). on these points, various authors have tried to devise a theory, starting from newton and gothe, who were among the first to propose the "chromatic circle" (vendler, 1995). since then, chromatic circles have been used as a tool to understand chromatic relations and create harmonious combinations of colors. the chromatic circle, which has been the basis of various studies (camgöz et al., 2002), clearly shows the distinction between warm and cold colors, which are complementary and similar. this is useful nowadays in the world of marketing, as will both color preference and the color used in different fields of marketing applications. the lack of scientific results related to color in the context of marketing has given rise to several speculations, including the private use of results that are not disclosed by many companies (bellizzi & hite, 1992). there have been some advances in research, although from companies in the color consulting industry, although in recent years there has been an increase in research in this field. although the nature of the experiments is not entirely scientific, the results seem to be generally shared by marketing professionals, which makes them applicable. some applications of color in marketing have been reviewed according to the guidelines of the prisma model (page et al., 2020). different inclusion and exclusion criteria were used for article selection (figure 1). figure 1. inclusion and exclusion criteria the selection of the articles was made by google scholar, being the source with the most results obtained, the selected articles have passed three phases; the first phase "identification,” where the articles containing the keywords "color in marketing" are selected, a search that is refined by selecting the keywords in the title and narrowing the publication period from 1999 to 2021. the second phase of "screening,” provides for the selection of articles based on the relevance of the work to the proposed review, in two ways, first, by reading the abstract of the reviewed work, articles that do not meet these parameters or that are unclear are excluded, second, all articles that have passed the first phase are read and will be discussed later (table 1.); older articles that had a common result obtained from more recent work, articles with repetitions, or unclear were excluded. table 1. summary review of major "color in the marketing", literature organized by area. 2.7 color used in store for “color used in-store" refers to two categories of approaches related to marketing, the first is packaging and the second is the colors used in-store design. the color of packaging attracts consumers' attention, creates aesthetic experiences, and gives symbolic value to a the promise of color in marketing: use, applications, tips and neuromarketing 81 color culture and science journal vol. 15 (1) doi: 10.23738/ccsj.150110 brand (garber et al., 2000; kauppinen-räisänen & luomala, 2010; labrecque & milne, 2012). product packaging is an essential component for communicating the meaning of the brand to consumers. especially at the time of purchase, packaging has been identified as the most important vehicle for communication (underwood & klein, 2002; van rompay et al., 2014). many researchers in the field (veryzer & hutchinson, 1998) argue that color is an essential feature of packaging design and a prominent component of the visual identity of the product (garber et al., 2000; labrecque & milne, 2012). similarly, the literature indicates that consumer categories’ perceptions incorporate specific expectations about the color options that branded packages typically employ within a given category (bottomley & doyle, 2006; labrecque & milne, 2012). this trend towards categorization creates a norm for the use of color in packaging. for the use of colors in-store design several studies have examined the use of color in a store and identified how it can affect the customer's stay in the store and the purchase of products. babin et al. (2003) suggested that color and lighting are important factors in purchasing intention. they applied two colors, blue (450 nm) and orange (590 nm), and two light sources (soft and bright). a blue interior was associated with more favorable ratings and greater purchasing intentions, but the use of soft lights with an orange interior canceled out its negative effects, and perceived price equity was higher. changes in the physical characteristics of a store are related to consumers’ mood, perceptions, and buying time. crowley (1993) stated that color affects both the affectivity and excitement of consumers. there is a ushaped relationship between excitement and wavelength, where extreme wavelengths evoke greater excitement. barli and colleagues show how color influences the time spent in a store and influences purchasing behavior; for example, green color influences the time spent in the store and has positive effects on the purchase of the product (barli et al., 2012). we have just seen how color is widely used and studied these two aspects of "color used in-store,” but the use of color in marketing is not limited to this. 2.8 color and brand according to hsieh et al. (2004), a successful brand image allows consumers to identify the needs that the brand meets and differentiates the brand from its competitors, and consequently increases the likelihood that consumers will buy the brand". are important in the process of building a brand for the first time. companies use a brand to create an experience and association, and color allows consumers to identify their corporate identities. some companies now live off their colors; an important example is coca-cola, just thinking of cocacola and we immediately think of red, or the opposite, if we think of red and we have to associate it with a brand in an almost automatic way we associate it with the famous brand mentioned above; this is just an example of how color can leave a positive memory on a brand (caivano & lópez, 2007). 2.9 color and trend one of the most difficult aspects to predict for a company is certainly the fashion trend; it is often associated with colors that become boring or obsolete with the passage of time (blumer, 2017). predicting color preference for a specific product is crucial for companies dealing with trends or time-dependent consumer products. in this regard, different models have been proposed that attempt to anticipate a preference for a given color. the first model, "autoregressive integrated moving average" (arima), is a method based on the integration of selfregression and moving averages (makridakis & hibon, 1997). second, an artificial neural network (ann) model is a computational model. it imitates the structure and function of biological neural networks (gurney et al. 1997). each ann consists of an interconnected group of artificial neurons that can automatically adapt their structure and parameters to learn data such that the ann can model sophisticated data relationships by mapping the input data to the output data. the last one the extreme learning machine (elm) (huang et al., 2004) is a variation of ann. in a typical three-layer feed-forward backpropagation ann, the parameters in the structure are tuned in the learning process. this model (thanks to the creation of an algorithm) is believed to be much faster than ann. given the complexity and unpredictability of fashion trends in the preference for a given color, in this field, the data until now appear very confused. 3. concluding remarks the results obtained from various studies in this field are very controversial; some authors believe that human responses to colors are stable (amsteus et al., 2015). therefore, they are applicable to everyone, while in reality, several individual differences make the use of color in marketing a very delicate point and not to be underestimated, and the responses and preferences to colors vary depending on culture, gender, and age (elliot, 2015). the problem with research in the field of color in the context of marketing is that the results obtained from scientific work when applied in a more ecological and "real" context are often not confirmed or even denied. any company before launching a product, opening a store, and proposing a new brand should implement and conclude research related to the choice of colors and the promise of color in marketing: use, applications, tips and neuromarketing 82 color culture and science journal vol. 15 (1) doi: 10.23738/ccsj.150110 analyze the preferences of its consumers according to age, gender, and culture of interest; this should be done before launching a product because the wrong choice of color can have a negative and disastrous impact on the image of the product and the company. let us try to summarize all of these points in figure.2 to make graphically clear and simple reactions between the various aspects of color and the various marketing contexts proposed. figure 2. "hypothetical model” one could think of "universalization of color preferences" in global/international marketing strategies, in fact in the historical era in which we find ourselves with the reduction of territorial barriers and progress in communications, both through social networks and television programs, should facilitate the homogenization of the use of colors throughout the world; making it easier for companies to select the most effective color. this hypothesis could be a double-edged sword for companies by making color marketing strategies simpler globally on the one hand, but on the other hand, it would make all "competing" companies similar by depersonalizing them. as this is a hypothesis, the extent to which color can become standard for a given geographical point depends on how much companies are striving to adopt such strategies during this period, and to what extent. it is hoped that this general framework will clarify crucial points for future interventions in this field. 4. neuromarketing and future research direction having shown the weaknesses regarding the difficulty of using color as a stimulus (especially in research on color and psychological functioning) we can see how applying them to marketing and the choices made by a potential consumer depends on many variables, and makes the whole thing very complex. the development of new technologies in the production and delivery of color (e.g., increasing of colors, digital color screens, and lower production costs) have altered the role that color plays in our lives, thanks to the variety of subjects and researchers from various fields, such as physicists, psychologists, and economists (just to name a few) are going to meet a more global vision of "color", which for now is still in its infancy but sees before it a great margin of development; this is also thanks to neuroimaging techniques that are very useful for the understanding of human behavior. another interesting approach could be to use a multisensory approach, as shopping experiences are influenced by different senses in combination (elder & krishna, 2021). a "modern change" that must be examined with updated research. undoubtedly, color research is critical to the advancement of marketing and presents a promising area of growth for marketing practices. from an innovative marketing perspective, the use of color in marketing strategies can be significantly improved and optimized with the help of neuromarketing. neuromarketing is a relatively new and rapidly growing field of study that combines the disciplines of neuroscience, psychology, and marketing to understand how consumers process and respond to marketing stimuli. it uses various tools and techniques, such as functional magnetic resonance imaging (fmri), electroencephalography (eeg), eye-tracking, and skin conductance response (scr), to measure and analyze the neural and physiological responses of consumers to marketing messages. one of the key benefits of neuromarketing is that it provides insight into consumer behavior that goes beyond self-reported data and conscious responses, allowing marketers to gain a deeper understanding of the unconscious drivers of consumer behavior, such as emotions and motivations. this can help brands better understand the impact of color on consumer perception and decision-making, and make more informed decisions on color selection and placement in marketing campaigns. for example, neuromarketing research has shown that different colors can evoke different emotions and stimulate different parts of the brain, which can influence consumer perception and behavior. red, for example, has been shown to stimulate the brain's attention center and evoke feelings of excitement and energy, while blue is often associated with calmness and stability. by understanding the emotional impact of different colors, brands can select the most appropriate colors for their marketing campaigns to create the desired emotional response in consumers. in conclusion, neuromarketing offers a valuable tool for marketers looking to understand and optimize the impact of color in marketing. by utilizing the latest advancements in psychology and neuroscience, neuromarketing can provide a more comprehensive and in-depth understanding of consumer behavior, allowing brands to make informed decisions on color selection and placement, resulting in more effective and impactful marketing campaigns. the promise of color in marketing: use, applications, tips and neuromarketing 83 color culture and science journal vol. 15 (1) doi: 10.23738/ccsj.150110 5. conflict of interest declaration nothing to declare 6. funding source declaration nothing to declare 7. short biography of the authors alessandro bortolotti psychologist and phd student in business and behavioral sciences at the university of chieti-pescara, where he studies neuromarketing and emotion using behavioral and neurophysiological methods. loreta cannito psychologist and psychotherapist in training, she obtained her doctorate in business and behavioral sciences at the university of chieti-pescara, where she deals with decision making and neuroeconomics. stefano anzani psychologist, he obtained his doctorate in business and behavioral sciences at the university of chieti-pescara. riccardo palumbo is professor of business and behavioural economics and neuromarketing at the department of neuroscience imaging and clinical sciences of the university of chieti-pescara. coordinator of the section of behavioural economics and neuroeconomics and the phd in business and behavioural sciences. co-founder and ceo of umana analytics licensing terms articles published in the “cultura e scienza del colore -color culture and science" journal are open access articles, distributed under the terms and conditions of the creative commons attribution license (cc by). you are free to share (copy and redistribute the material in any medium or format) and adapt (remix, transform, and build upon the material for any purpose, even commercially, under the following terms: you must give appropriate credit to authors, provide a link to the license, and indicate if changes were made. you may do so in any reasonable manner, but not in any way that suggests the licensor endorses you or your use, you may not apply legal terms or technological measures that legally restrict othersfrom doing anything the license permits. copyright: the authors keep the rights to further publish their contents where they want and can archive pre-print and post-print (submitted version and accepted version) and the published version of the pdf of their article with no embargo period. references al-rasheed, a. s. 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(2009). consumer decision making and aging: current knowledge and future directions. journal of consumer psychology, 19(1), 2-16. https://doi.org/10.1016/j.jcps.2008.12.002. cultura e scienza del colore color culture and science 61 cultura e scienza del colore color culture and science | 06 | 2016 issn 2384-9568 1giulia pellegri pellegri@arch.unige.it 1department of architecture and design, university of the study of genoa, polytechnic school chromatic and decorative planning choices: geometry, knowledge and survey abstract this study wants to highlight the complex planning and technological/procedural choices in order to address all types of painted façades’ intervention: conservation, maintenance and restauration. the major difficulties in surveying the historical façades’ painted decoration, depend mainly on the conservation conditions of the same, on the building support, on the degree of legibility of compositional scheme, on the cultural sensitivity of the researcher and on the objective knowledge of the different types of plastics and painted ornaments of historical architecture. the methodology includes: study of historical treatises on the art of drawing of the architectural orders, study of historical treatises on geometry (study of shadows), study of the theories of color and the repercussions on the current methodology survey painted decorations with the direct method and computer graphics. so the complex research is to ensure through finding colors and decorative types of individual cases and of their building as a whole understanding the rules and the methods ‘ use of decorative repertories, of colors of materials and of the execution techniques of compatibility historical / figurative design. the planning choices regard principally the two components: • compositional structure and decorative façade • color values of all the elements of the façade. keywords survey, colour, decorations, geometry, planning, digital citation: pellegri g. (2016) ‘chromatic and decorative planning choices: geometry, knowledge and survey’, cultura e scienza del colore color culture and science journal, 06, pp. 61-69, doi: 10.23738/ccsj.i62016.06 received 5 february 2016; revised 22 september 2016; accepted 23 september 2016 giulia pellegri is associate professor in drawing scientific disciplinary sector, department of architecture and design -polytechnic school of genoa-italy , and member of the architecture and design graduate school. research interests: urban and environmental survey, drawing representation of analogic and digital techniques, geomatics aimed to the conservation and restoration and colour measurement systems. 62 cultura e scienza del colore color culture and science | 06 | 2016 | 61 69 pellegri g. issn 2384-9568 doi: 10.23738/ccsj.i62016.06 1. introduction this study wants to highlight the complex planning and technological/procedural choices in order to address all types of painted façades’ intervention: conservation, maintenance and restauration. the major difficulties in surveying the historical façades’ painted decoration, depend mainly on the conservation conditions of the same, on the building support, on the degree of legibility of compositional scheme, on the cultural sensitivity of the researcher and on the objective knowledge of the different types of plastics and painted ornaments of historical architecture. the painted decorations often follow exactly the compositional schemes of orders in architecture but, depending on the historical, economic and cultural period different types of decoration can be distinguished such as: architectural elements, ranging from the simple to the most complex structural and spatial moldings partitions; architectural elements intermingled with individual figures located in front of the prospective apparatus or in other cases inserted into them, in order to assume themselves the role of structures; figurative subjects inside large panes, historical or mythological scenes, allegorical figures or personification of the political and military power with their symbolic meanings.[1] the knowledge of the treatises, of the study of historical texts on the “ornaments” and of the notions of teaching about the possible compositions of the architectural decorations and their proportions with the study of shades, are fundamental for the purposes of painted decoration survey and conservation. on this basis this study analyzes the relationship between the color and the drawing in the context of external finishes of the historical façades, how much the drawing defines the color or vice versa how much color composes the drawing through the balance among color fields and combinations of hot and cold. it’s fundamental to highlight how the drawing and the color are related to the potential conditionings that may accentuate, mitigate, reduce or differentiate the individual elements, making a proportionate or perceptually distorted building, through the research about the drawing of the patterns and the visual perception of painted decoration. this research analyzes the drawing of the shadows through the study of the shape, of the depth and of the thickness, the painting technique of chiaroscuro and the proper use of color. is drawing color and/or is the color shape and so drawing? this question is often at the base of the problem of the study and of the revival of the façades’ painted decoration and it concerns many issues that arise as the fundamental approach to the problem. this paper proposes a methodology for the research aimed to investigate the relationship among drawing, color, plastic and painted façades’ decoration. the methodology includes: study of historical treatises on the art of drawing of the architectural orders, study of historical treatises on geometry (study of shadows), study of the theories of color and the repercussions on the current methodology survey painted decorations with the direct method and computer graphics. 2. drawing father of the arts: architecture, painting, sculpture che cosa sia disegno, e come si fanno e si conoscono le buone pitture et a che; e dell’invenzione delle storie. perché il disegno, padre delle tre arti nostre architettura, scultura e pittura, procedendo dall’intelletto cava di molte cose un giudizio universale simile a una forma overo idea di tutte le cose della natura, la quale è singolarissima nelle sue misure, di qui è che non solo nei corpi umani e degl’animali, ma nelle piante ancora e nelle fabriche e sculture e pitture, cognosce la proporzione che ha il tutto con le parti e che hanno le parti fra loro e col tutto insieme (g. vasari, le vite de’ più eccellenti pittori, scultori e architettori, vol.i della pittura, cap. xv, 1550,edizione giuntina) vasari sees the technique of the art all enclosed in drawing where we can find the values of ideation, introducing a first classification of the drawing techniques according to the degree of complexity. in his treaty, vasari clearly distinguishes sketches, intended as hint touches, from draws, intended as a defined section with profiles and contours essential for the architecture, sculpture and painting. [2] but even in the book of art, 1390, cennino cennini places the painting second only to the science: “the foundations of the art are drawing and colour”, highlighting a good amount of techniques and supports of the art. in the fifteenth century treaties pay more attention to the “linear drawing”, which allows a greater detachment from reality and therefore a greater focus on pure composition. the renaissance treatises emphasize the importance of drawing, seen as the main skill required for anyone who aspires to become an architect. sebastiano serlio tutte l’opere d’architettura, et prospectivae, 1538 was one of the most popular books during the sixteenth century; the beginning of book ii observed that 63 cultura e scienza del colore color culture and science | 06 | 2016 | 61 69 chromatic and decorative planning choices: geometry, knowledge and survey issn 2384-9568 “the perspective would be nothing without the architecture and the architect would be nothing without the perspective.” (figure.1) serlio pointed out how all the greatest architects of his time, bramante, raffaello, peruzzi and giulio romano, had started out as painters. in the new division of labor that took shape during the fifteenth and sixteenth centuries, what constituted a new genus of architects, regardless of the construction industry, was their mastery of drawing. this made it possible to separate their activities from construction and design, due to the link between the drawing and the geometry made possible by the new science of perspective. this period bound architecture to abstract thinking, guaranteeing the status of intellectual labor rather that manual. within the new division of labor, the drawing was the only part of the process of building production on which the architects maintained an absolute and exclusive control. leon battista alberti reinforces this idea by asserting that “it is possible to draw all forms in the mind without any recourse to the material.” on the one hand the drawing was entrusted with the vital responsibility to convey the idea from the mind of the architect to the created building , but on the other hand the drawing suffered from the disadvantage of being always considered inferior to the idea and, finally, to degrade it. in practice, this tension was resolved generally overestimating the accuracy of the orthogonal projection and exaggerating the falsity of perspective. alberti was the first to do this: “the difference between the drawings of the painter and of the architect is as follows: the first seeks to emphasize the importance of the objects in the painting through the light figure 1 s.serlio, tutte l’opere d’architettura, et prospectivae, venice, ed. 1600 and shade by thinning the lines and angles; the architect rejects the light and shade , but he gets its projections by the plan and, without altering the lines and keeping the actual angles, reveals the extent and shape of each prospect and of every side.” [2] a very interesting graphical approach is the book “perspectiva pictorum architectorum” by andrea pozzo, romae, 1693 with the attached tables of the prospective study from different points of view and the study of light and dark, particularly important for the technique of trompe l’oeil. a. pozzo doesn’t limit himself to writing a theoretical treatise, but he has the merit of teaching the way to put into perspective all the architectural drawings, to use both for painters and for architects, “the deception of the eye, can be achieved only through a knowledge and a thorough study of the perspective technique. this is the ambition of my book “(so a. pozzo writes in the dedication to the future habsburg emperor joseph i). the first part is about the basic canons of matter, the second part is about the operational procedures for drawing in perspective domes, altars, fountains, stairs and other architectural elements. the treaty is placed in the established tradition of architectural treatises such as palladio, serlio, vignola and scamozzi. the artist, however, differs from these illustrious names, elaborating a treaty that explores the art of perspective in all its variations and applications: architecture, painting, theater, ephemeral apparatus. the jesuit artist can without doubt be considered the supreme representative of the quadraturism representation . 64 cultura e scienza del colore color culture and science | 06 | 2016 | 61 69 pellegri g. issn 2384-9568 doi: 10.23738/ccsj.i62016.06 the quadrature’s painters, making use of knowledge about the geometric perspective and the techniques of pictorial representation on large wall surfaces, reproduce spectacular spatial effects through the drawing of architectural elements real or imaginary. in the fifteenth century the interest of painters, sculptors and architects focuses on the problems of linear perspective and in this context there are the first symptoms of the distinction between painting figures and architecture. the passage of the decorative painting, from ornamental architecture to connection with the depicted scenes and, later , to the development and completion of the building structure itself, is marked by the application of the principles of linear perspective to architectural frameworks and architectonic backgrounds . in the late seventeenth-century rome, pozzo represents the top of baroque visual culture that stems from a bold artistic experimentation exalting, with unpublished proceedings, the allusive power inherent in the image space. (figure 2) [3] with the drawings of the treaties of the eighteenth and nineteenth centuries, the study and the use of shadow confirm, unlike alberti, one of the foundational aspects of the drawing representation. the “draw” achieves the highest academic reputation in the nineteenth century, thanks to the lessons imparted by the academies in europe, where the watercolor technique was widely considered to be essential to give a more incisive and popular character to the performance, because, unlike the linear perspective, which presupposes an intellectual process in the understanding of the design, and the watercolor, and the use of shadows are an expression of easily understandable language forms. figure 2 pozzo andrea, perspectiva pictorum architectorum , romae, 1693 3. conclusion: survey drawing application for the methodological approach, the survey plays a vital role in reaching the historical/ critical and formal knowledge both quantity and quality aspects of the historical fronts’ finishes, ranging from those historical, figurative and perceptual to the technical ones reaching the valence of incontrovertible documentation of the state of art , and tool of guidance and control , in order to avoid arbitrary choices. the critical survey, beyond the measurements and related graphic representations through plans, sections and elevations, becomes fundamental to address the typological study of the urban fabric i.e the processes that characterize an urban organism in the succession of its evolutionary phases. it’s necessary to read the architecture as the result of a multiplicity of interventions in the realization of urban spaces highlighting the actual development through the basic building, the remelting and the superfluous . a fundamental study for the achievement of quality is the decorative historic structure, even in the simplest cases , always arises in interrelation with the overall architectural structure to prevent figurative distortion and ungrammatical remakes. so the architectural survey of the fronts with the overall decorative structure, must be articulated at different scales. the critical survey together with the graphic description a method of search about the fronts’ characters is the main cognitive tool of quality survey and secondly the dimensional proportionate scheme in order to distinguish and describe the decorations, the types and the materials, from the sketch to the development 65 cultura e scienza del colore color culture and science | 06 | 2016 | 61 69 chromatic and decorative planning choices: geometry, knowledge and survey issn 2384-9568 of the relationship between architecture and decorations (architectural order –color) . so the complex research is to ensure through finding colors and decorative types of individual cases and of their building as a whole understanding the rules and the methods ‘ use of decorative repertories, of colors of materials and of the execution techniques of compatibility historical /figurative design . the planning choices regard principally the two components: 1 compositional structure and decorative facade 2 color values of all the elements of the façade. the analyses have a sense and a consequence design with the study of the decorative color -treatment of the facade from the simplest monochrome to the most complex types with painted polychrome decorations extended to all part of the façade through direct and instrumental tools (measurement, photography, infographic photo rectifier with shields and processing of contrast..). the study of the painted decoration, as mentioned above, can’t be tackled without the depth and knowledge of the treaties, architectural orders, the study of descriptive geometry and the rules and applications of the drawing first and of the color then. particularly interesting for the purposes of restauration and/or the project of facades’ painted decoration, are: rules for drawing the several parts of architecture gibbs, james london, 1736: the city and country builder ‘s and workman ‘s treasury of designs or the art of drawing and working the ornamental parts of architecture figure 3 the city and country builder ‘s and workman ‘s treasury of designs: or, the art of drawing and working the ornamental parts of architecture langley, thomas london, 1740 langley, thomas london (figure 3), 1740 and the principles of architecture nicholson, peter london, 1795-1798 (figure 4), that are actual implementation of practical manuals about architectural decoration and composition of the façade. at first they follow the practical and organic characteristics; then process in an aesthetic sense without losing distinctive character, until in a final stage of stylistic development break down sharply from the element structure; to give a rhythm in architectural compositions, emphasizing the wealth of some areas and aesthetically changing relationships. the first type of decorative expression is inherent in the materials, the design is obtained by processing of surfaces flat, rustic ashlar, and imaginative forms of the renaissance. the aesthetic transfiguration of the architectural elements is due to two methods: geometric procedure and reproduction of the essential aspects of the nature both from the point of view of the design of that of color. the application of stucco depicting the elements of nature and the architectural orders in the renaissance has extensive use of decoration on the façade, while in the seventeenth and eighteenth centuries are used in order to free decoration from any constraint other than that of the general architectural framing. the first of these applications simulate the architectural elements of stone (frames, ashlars, shelves) or mimic, in the more strictly ornamental expressions, garlands, shells, drapes, or foliage. then they gradually assume fantastic character, which only remotely reminiscent of ancient models, in broken curves frames, twists, plaques, flourishes of any kind. the color was almost constantly used, sometimes 66 cultura e scienza del colore color culture and science | 06 | 2016 | 61 69 pellegri g. issn 2384-9568 doi: 10.23738/ccsj.i62016.06 as indispensable attribute of the form, or with overlay colors to construction elements, or with the coating of paint entire wall surface, or with the combination of different polychrome materials.[4] the first step is to define the decorative signs of the façade in proportional relationship to the study of the component parts, identifying, at the same time, the base color and then the ornaments’ color. for this reason, the composition of the façade, simple or complex, takes into account the primary structures of the building i.e. the vertical and horizontal ties. (figure 5) the approach exemplifying the types of decorative facades led to the identification of three basic types: monochrome bottom front and basement with simple decorative elements (frames) monochrome bottom front with monochrome base or ashlars with decorative elements or simple (and frames antheridia) and monochrome bottom front with base monochrome ashlars or complex with decorative elements (framesantheridia-pilasters-panels and other decorative elements). the use of bringing back in front the structural nature of the building and especially the highlighting of the main floor has caused in the visual-perceptual formal habit, that has conditioned the decorative design choices to the point of incorporating two floors in a decorative order so to donate luxuriousness that internally does not exist. figure 4 (1-2-3-4) the principles of architecture nicholson , peter london, 1795-1798, (5)panel of study at the academy of fine arts in genoa. on the right study on compositional decorative pattern for the color project in savona (italy) through infographic photo rectifier with shields and processing of contrast. figure 5 survey and drawing representation of the painted decoration of facades.historical centre of genoa. 67 cultura e scienza del colore color culture and science | 06 | 2016 | 61 69 chromatic and decorative planning choices: geometry, knowledge and survey issn 2384-9568 the decoration is also meant to recreate a harmony of “lost” proportion, adapting the decorative elements to spaces. the wide panorama of case studies, which emerged at the meeting in rome “coatings, colour, colouring of buildings and historic” in 1984, sponsored by the ministry of environmental, exceeds the two extreme positions of restauration all short , or restore an outright original color, which often no longer has any acknowledgment nor with the current reality, nor with more recent historical memory. [5] where overexposed theories do not find possibilities of application, to attain an appropriate harmonic relationship of the colors to be used, we should refer to the theory of colors applied to wall surfaces that receive the color. in this case, by referring to the color table, the design directions want to highlight a line of intervention in the choice of the chromatic colors of the facade in order to avoid that between the painting of two neighboring buildings there is a chromatic saturation deviation exceeding 15% and of more than 10% color brightness. [6] (figure 6) in the treatise grammar of ornament, o. jownes describes the use of colors connected to the plaster and painted architectonic decoration (proposition n. 14-15-16-17-18). [7] a right approach to the choice of colors in the painted decoration of the façades is in the awareness that it is influenced by the ratio of the proportion between the parties given by perception especially by the contrast of simultaneity [8]: definition of the decorative composition and identification of the different color fields, through the study of individual components and of the relationship between the color of light and shade. the planner, once identified the decorative “types” arises the problem of verifying the wanted prospective study perceptual in relation to the environment and to the visual quality of the façade. the restoration of the painted decoration is the result of an accurate survey of the historical traces in order to reproduce, as closely as possible, the spirit of the original work. the direct survey, the drawing from life, the investigation, also photographic, from the panoramic to the details are the early steps of analysis aimed to color plan of painted facades. the compositive architectural façade was created as an expression of the lexical composition of the aggregation highlighting the architectural building elements and their interconnections. from drawing to wire, the yield of shapes, surfaces, contours through tones and graphic textures, up to a constant enrichment of personal stock of signs and techniques, everything becomes essential to understand an architectural detail, the relationship between architecture and urban configuration or landscape. drawing from life is depiction, critic visualization, communication, but this figure 6 synthetic scheme of urban and environmental survey in the ambit of the research agreement: the ancient center of albenga, analysis, surveys and profiling aimed at recovering and restoring the color value. 20122013 scientific responsible g.pellegri 68 cultura e scienza del colore color culture and science | 06 | 2016 | 61 69 pellegri g. issn 2384-9568 doi: 10.23738/ccsj.i62016.06 obvious assertion is precisely the most difficult to achieve, because, after a long time, you have the powers of observation and execution and the readiness of reading the real meanings that allow you to translate the observed reality in an image rich in meaning and can convey to those who view the drawing, the relationship established between reality and draftsman. just as a subjective model of reality always different and changing, still-life drawing is the result of a complex set of shape analysis, for immediate application of geometric concepts, of tonal evaluation, of the characters’ selection, knowledge of graphic techniques and, of course, of critical consciousness. in practice drawing from life allows us to figure 7 1 – photograph of detail of a painted façade in genoa cornigliano; 2.infographic photo rectifier with shields and processing of contrast; 3. development by chromatic variation curves of contrast; 4. color correction automatically by algorithms, clipping colour channels to increase the contrast and correct colour casts; 5 a-b-c-. last steps with the addition of algorithmic processing aimed to find the bright and the dark to use as light and shadow figure 8 exercise of painting façades decorations at the academy of fine arts in genoa and the typological scheme of the color project section for the painted decorations of the ancient center of albenga 69 cultura e scienza del colore color culture and science | 06 | 2016 | 61 69 chromatic and decorative planning choices: geometry, knowledge and survey issn 2384-9568 observe how things change depending on the brightness, the distance from the point of view and proximity to other elements; it allows us to understand that the technique must not prevail on observation and transcription of meanings. this research highlights how the images acquired during the photographical survey are altered by computer graphics systems first with photorectifier and then with shields contrast, with the study of tone and of colorimetric curves in order to identify the different color tones. (figure 7) at academy of fine arts in genoa, the students approach to the decoration of façades through the application of the drawing and the color theories painting panels starting with sketches on paper and proceeding with the fresco technique. from drawing to wire it goes to dust and then to the pave of the color tests with the same procedure with which we apply the chiaroscuro on painted façade, starting with the drafting of the basic colors. in the first phase are applied the 1st dark, the 1st light and the first shadow on the bottom so as to make threedimensional drawing. then you apply the 2nd dark (for a darker tone) and the 3rd dark (still a darker tone), the relights (a lighter tone) and the second drop shadow. the final touch is given by a dark reddish-brown that is used to give more depth (figure 8). funding this work was supported by the search agreement made between the municipality of albenga, the industrial union of savona and the department of sciences for the architecture, university of genoa, italy, responsible scientific giulia pellegri. 2011-2012 color project of the historic center of albenga. conflict of interest potential conflicts don’t exist. bibliography [1] g. rotondi terminiello, “le facciate dipinte a genova: note per una metodologia di restauro”, ministero per i beni e le attività culturali bollettino d’arte, suppl. n.6, roma, 1984. [2] g. vasari, “le vite dei più eccellenti pittori, scultori e architetti”, edizione del 1568, firenze. [3] f. di stefano, “l’effimero e l’illusione in età barocca”, 2011, e-book per l’arte. [4] v. fasolo , la decorazione, enc, treccani, ed.1931 [5] p.falzone (a cura di), “colore, architettura, ambiente”, kappa ed., bologna, 2008. [6] g. pellegri, f.salvetti, “analisi, rilievi e schedature dei valori cromatici del centro antico di albenga. il progetto di conoscenza e le fasi operative”. alinea ed., firenze, 2012. [7] o. jones, “the grammar of ornament”, londra, beenard quaeitch, 1868. [8] j. itten, “arte del colore. esperienza soggettiva e conoscenza oggettiva come vie per l’arte”, milano, il saggiatore,1965. cultura e scienza del colore color culture and science 82 cultura e scienza del colore color culture and science | 06 | 2016 | lecca m. and da pos o. issn 2384-9568 1michela lecca lecca@fbk.eu 2osvaldo da pos osvaldo.dapos@unipd.it 1fondazione bruno kessler, center for information and communication technology, technologies of vision, trento, italia; 2università degli studi di padova, italia communications and comments this page originates to promote and stimulate the exchanges of ideas and comments among the members of the associazione italiana colore. in this framework, the page is inspired by the classic greek philosophy of socrates, which considered the dialog among respectful speakers as an important tool to achieve and enrich the human knowledge. in this number, we report the ideas and comments expressed by seven members of the gdc during a workshop, organized in september 2014 by prof. osvaldo da pos as a satellite event of the 10th color conference and hosted by università degli studi di genova (italy). the workshop, entitled “what is the color for me?”, aimed at collecting the viewpoints of the participants about color. the attenders were asked to define color, to explain how they use color in their work or in their day life, which are the characteristics and the functions of the color they consider important and why, how they deal with color, who is the people working with color. any other issue they felt relevant was welcome. the apparently trivial question of the title was addressed in different ways by the speakers. the final result was an interesting vision of the polymorphous entity “color”, directly derived from the individual experience of the participants. three definitions of colors have been provided during the workshop. the first one was given by osvaldo da pos, senior scientist and professor at the università degli studi di padova (italy). he defined the color as a mental tool that humans use to interact with the world. in this respect, color is not a physical property of the objects, rather it is an instrument of the perception mechanism. prof. da pos explained this idea by an example. let us consider a spaceship, which travels across the universe and suddenly stops under the influence of an unknown entity. the board scientists make experiments and collect data in order to develop a new technology allowing humans to interact with the unknown entity and to continue their trip. after many studies, the scientists represent some features of the field of forces by colors and develop a color based model, where a color variation corresponds to a variation of some characteristic of the mysterious object that stopped the spaceship. these colors, that are called pseudo-colors to be distinguished from the colors are physical radiations, help people to interact with the new body and thus to plan their further actions. the second definition was given by michela lecca, researcher at the research unit technologies of vision of the fondazione bruno kessler (trento, italy). she reported the mathematical formalism of color, as it is used in computer vision. in this framework, the color of a certain point in an observed scene, captured by a camera, is modeled by a mathematical equation, termed the “image formation equation”. this models the color response of a camera in imaging science and computer vision, where color plays a crucial role in many applications, e.g. object recognition/ tracking, and image retrieval. the third definition of color was shared by all the speakers: color is a powerful communication tool. michela lecca gave some examples of color as communication tool in science: colors τό διαλέγησθαι εστί τό μήγιστον αγαθόν the dialog is the highest good. [socrates] coloumn 83 cultura e scienza del colore color culture and science | 06 | 2016 | coloumn. communications and comments issn 2384-9568 are used to distinguish or highlight concepts in a text (e.g. a book or a scientific presentation); colors improve the understanding of data, collected in a table or plotted in a graph like a pie chart, where colors are employed as legend; they can be used also as unit measure, like in the case of the litmus test for quantifying quickly the ph of a chemical substance. renata pompas, specialist of color and textile design, described the content of a course she organized some years ago about inject printable surfaces. one part of this course was devoted to study how the choice of a certain palette of colors can be interpreted by an observer and what a color can communicate also from a symbolic point of view (this color is cold, warm, heavy). renata also addressed the verbal and visual communication of the color: the verbal communication consists in creating cromonyms, i.e. words that indicate an object through its color and vice-versa; the visual communication relates to the synesthesia, where colors are perceived not only by eyes but also from other senses. an example of color based synesthesia was reported also by francesca valan, industrial designer with strong competences on color. she described an event organized by the ricordi music school during the exposition van gogh alive in febuary 2014. one hundred children of the under 13 orchestra played some well known classic music pieces of mozart, verdi, bardok, piazzolla, hisahishi, shostakivoic, and naglieri. at the same time, other hundred children associated a color to each playing instrument, e.g. emerald to clarinet, black to oboe, cobalt blue to trumpet, cadmium yellow to violin. the synesthetic relationship between color and music was experienced also by vincent van gogh that compared his paintbrush to the fiddlestick. the definitions given above implicitly reveal two important functions of color: the interaction with the surrounding world and the communication of data and emotions. in her talk, michela lecca also mentioned the function of color as a powerful descriptor of the visual appearance of objects in daily life as well as in technology. anna marotta, professor at the department of architecture of the politecnico of torino (italy), explained the relationship of the color with other features relevant to architecture. her 84 cultura e scienza del colore color culture and science | 06 | 2016 | lecca m. and da pos o. issn 2384-9568 analysis showed that the choice of a certain color for an architecture project strongly depends on a number of different factors: among the others, the historical and cultural context, the geographic position and its topology, the global and local illuminant conditions, the physical and chemical characteristics of the materials, the perception of the users, the symbolic meaning of a color into a certain community, the final usage of the product. designing color is thus a complex procedure that investigates many issues and requires many different competences. there are artists, scientists, architects, designers working with color. to giulio bertagna, architect of b&b colordesign in genova (italy), all these professional figures are characterized by a large amount of creativity, that it is the raw material for solving problems, pushing innovation, and stimulating emotions. but they have very different cultural background, so that they approaches a same problem differently. to giulio, for example, an architect that proposes a certain project bases his work on a social, historical, almost philosophical analysis. he does not consider more technical issues, such as the physical properties of the materials that will be used to realize its project. these are questions for engineers and/or scientists. in this mosaic, a tessera is still missing: it is the work of the color designer, that chooses the colors in order to harmonize the project according to the neurophysiological principle of the human perception. color designing is not decorating, rather configuring a scene where color is perceived as an intrinsic property: “this is the difference between to paint a wall and to configure a scene”, as giulio told. to conclude, the talks presented at the workshop showed very different positions about color, that appeared as a complex, multi-facetted entity. cultura e scienza del colore color culture and science 08 17 riv is ta s em es tr al e | h al fye ar ly jo ur na l | d o i: 10 .2 37 38 /c c sj .0 0 rivista dell’associazione italiana colore www.gruppodelcolore.it doi: 10.23738/ccsj.i82017.00 cultura e scienza del colore color culture and science 08numero 08 dicembre 2017 number 08 december 2017 cultura e scienza del colore color culture and science rivista dell’associazione italiana colore registrazione presso il tribunale di milano al n. 233 del 24.06.2014 gabriel marcu (apple, usa) anna marotta (politecnico di torino, it) manuel melgosa (universidad de granada, es) anna grazia mignani (ifac-cnr, it) annie mollard-desfour (cnrs, fr) maria luisa musso (universidad de buenos aires, ra) claudio oleari (università degli studi di parma, it) galina paramei (liverpool hope university, uk) laurence pauliac (historienne de l’art et de l’architecture, paris, fr) silvia piardi (politecnico di milano, it) marcello picollo (ifac-cnr, it) renata pompas (afol milano-moda, it) boris pretzel (victoria & albert museum, uk) noel richard (university of poitiers, fr) katia ripamonti (cambridge research system, uk) alessandro rizzi (università degli studi di milano, it) maurizio rossi (politecnico di milano, it) jodi l. sandford (università di perugia, it) raimondo schettini (università degli studi di milano bicocca, it) gabriele simone (st microelectronics, it) andrea siniscalco (politecnico di milano, it) ferenc szabó (university of pannonia, hu) mari uusküla (tallinn university, ee) francesca valan (studio valan, it) ralf weber (technische universität dresden, de) alexander wilkie (charles university in prague, cz) cultura e scienza del colore color culture and science rivista semestrale dell’associazione italiana colore http://jcolore.gruppodelcolore.it/ issn 2384-9568 doi: 10.23738/ccsj.00 ance e227716 direttore responsabile | editor-in-chief maurizio rossi (politecnico di milano, it) redazione | associate editors aldo bottoli (b&b colordesign, it) daria casciani (politecnico di milano, it) davide gadia | deputy editor (università degli studi di milano, it) marco gaiani (università di bologna, it) silvia piardi (politecnico di milano, it) alessandro rizzi (università degli studi di milano, it) francesca valan (studio valan, it) editorial board members john barbur (city university london, uk) giovanni bartolozzi (ifaccnr, it) berit bergstrom (ncs colour ab, se) giulio bertagna (b&b colordesign, it) janet best (natific, uk) aldo bottoli (b&b colordesign, it) patrick callet (école centrale paris, fr) jean-luc capron (université catholique de louvain, be) daria casciani (politecnico di milano, it) osvaldo da pos (università degli studi di padova, it) bepi de mario (crasmi, it) hélène declermont-gallernade (chanel parfum beauté, fr) reiner eschbach (xerox, usa) alessandro farini (ino-cnr, it) christine fernandez-maloigne (university of poitiers, fr) renato figini (konica-minolta, eu) raffaella fontana (ino-cnr, it) davide gadia (università degli studi di milano, it) marco gaiani (università di bologna, it) robert hirschler (serviço nacional de aprendizagem industrial, br) sandra krasovec (fashion institute of technology, usa) francisco imai (canon, usa) matteo lanaro (università degli studi di milano, it) lia luzzatto (color and colors, it) kevin mansfield (ucl, uk) veronica marchiafava (associazione italiana colore, it) peer review process tutti gli articoli inviati alla rivista “cultura e scienza del colore color culture and science” sono sottoposti ad un processo di revisione secondo la seguente procedura: prima revisione gli associate editors valutano ogni articolo per determinare se il tema e il contenuto sono di interesse per la rivista “cultura e scienza del colore color culture and science”. una volta valutati gli articoli, gli associate editors selezionano una serie di revisori scegliendoli scegliendoli nell’editorial board in base all’esperienza degli stessi in un particolare settore disciplinare o tema. seconda revisione ogni articolo è revisionato da due revisori in un processo in cui essi stessi e gli autori sono mantenuti anonimi. ai revisori è chiesto di valutare l’articolo considerando la sua originalità, la metodologia applicata e l’impatto sulla ricerca o sulla pratica professionale. dopo aver raccolto i commenti dei revisori, gli associate editors elaborano ed inviano al direttore responsabile un giudizio riassuntivo sull’accettazione o meno dell’articolo. collaboratori | contributors lynne bartlett, daria casciani, osvaldo da pos, agapito di tommaso, ivano forte, vincenzo garro, anna maria gueli, maria pompeiana iarossi, agata kwiatkowska-lubanska, michela lecca, sabina martusciello, maria dolores morelli, giampiero mele, stefania pasquale, alessio pietrini, renata pompas, maurizio rossi, michela rossi, desirée sabatini, mauro sabatini, ilma schiavitti, anna luana tallarita editore | publisher gruppo del colore – associazione italiana colore www.gruppodelcolore.it sede legale: piazza carlo caneva, 4 20154 milano (italia) all articles submitted to “cultura e scienza del colore color culture and science” journal are peer-reviewed according to the following procedure: first review the associate editors evaluates each article in order to define if the topic and content is suitable for consideration by the “cultura e scienza del colore color culture and science” journal. once the article passes the initial review, the associate editors select several referees in the editorial board based on their expertise in the particular field or topic second review each article is reviewed by two or three referees under a double-blind peer review process where the authors and the reviewers are kept anonymous. referees are asked to evaluate the manuscript based on its originality, methodology and impact to research and relevance to the professional practice. after collecting the referees’ reports, the associate editors makes a recommendation on the acceptability of the article to the editor in chief. doi: 10.23738/ccsj.i82017.00 gruppo del colore associazione italiana colore sommario | summary english | italian review 08 5 7 23 35 47 53 59 65 75 79 editorial by maurizio rossi principles and applications. consistency and experimentation in the work of piero bottoni, from the “cromatismi” to sesto san giovanni principi e applicazioni. coerenza e sperimentazione nell’opera di piero bottoni, dai “cromatismi” a sesto san giovanni by michela rossi, maria pompeiana iarossi, giampiero mele colour quantity contrast in itten’s theory: spectrophotometry for verifying statements il contrasto di quantità nella teoria di itten: la spettrofotometria per la verifica degli enunciati by agapito di tommaso, vincenzo garro, anna maria gueli, sabina martusciello, maria dolores morelli, stefania pasquale the recovery of the original colour of the archive material: the digital colour correction of the ancient anti-semitic discourse of the duce in 1938 il recupero del colore originale dei materiali d’archivio: la correzione digitale del colore dello storico discorso antisemita del duce, nel 1938 by desirée sabatini, ivano forte, ilma schiavitti, mauro sabatini, alessio pietrini the meanings of the red le significazioni del rosso by anna luana tallarita an overview of the history of the use of colour in jewellery by lynne bartlett colour as a mass product. designing of the collection of interior paint colours for the polish market by agata kwiatkowska-lubanska exploring the relationship between leds lighting, urban materials chromaticity and people: measurements, design and evaluation by daria casciani, maurizio rossi riccardo falcinelli “cromorama. how color changed our gaze” by renata pompas communications and comments by michela lecca and osvaldo da pos coloumn english 4 cultura e scienza del colore color culture and science | 08 | 2017 issn 2384-9568 this page has been intentionally left white 5 cultura e scienza del colore color culture and science | 08 | 2017 issn 2384-9568 con la pubblicazione del n 8, la rivista “cultura e scienza del colore color culture and science” ha completato il suo quarto anno di vita. da due anni la rivista pubblica solo articoli in lingua inglese o bilingue. sul sito sono disponibili il codice etico, il processo di peer review e le istruzioni dettagliate per gli autori. ogni articolo è indicizzato da un codice doi e per ogni articolo pubblicato vengono dichiarate le date di ricezione, referaggio e accettazione, oltre alle eventuali fonti di finanziamento ed eventuali conflitti di interesse. tutti questi criteri, oltre ad altri già introdotti da tempo, ci consentiranno dal 2018 di avviare la procedura per richiedere di essere inseriti nei database di indicizzazione internazionali. la rivista è edita da una associazione multidisciplinare che vede nel tema del colore il suo punto di riferimento. anche in questo numero abbiamo un chiaro esempio di integrazione multidisciplinare. michela rossi, maria pompeiana iarossi e giampiero mele, nell’articolo “principi e applicazioni. coerenza e sperimentazione nell’opera di piero bottoni, dai cromatismi a sesto san giovanni” analizzano, tramite gli strumenti di indagine della rappresentazione, il lavoro dell’architetto piero bottoni, dai cromatismi presentati alla iii biennale di monza del 1927, al palazzo comunale di sesto san giovanni degli anni ’60. nell’articolo “il contrasto di quantità nella teoria di itten: la spettrofotometria per la verifica degli enunciati”, agapito di tommaso, vincenzo garro, anna maria gueli, sabina martusciello, maria dolores morelli e stefania pasquale, tramite un’analisi storica e metrologica, partendo dagli scritti di schopenhauer, trattano il tema della paternità del concetto di contrasto di quantità dei sei colori primari della teoria di itten. desirée sabatini, ivano forte, ilma schiavitti, mauro sabatini e alessio pietrini nella ricerca “il recupero del colore originale dei materiali d’archivio: la correzione digitale del colore dello storico discorso antisemita del duce, nel 1938” si occupano di colore digitale, illustrando i presupposti scientifici e metodologici che sono stati utilizzati nella digitalizzazione e restauro di un filmato del 1938 conservato presso l’archivio storico luce. nell’articolo “le significazioni del rosso” anna luana tallarita prosegue le sua ricerca storica sul colore rosso. lynne bartlett in “an overview of the history of the use of colour in jewellery” presenta un interessante analisi storica dei materiali e metodi di lavorazione utilizzati nella realizzazione dei gioielli dalla preistoria ai giorni nostri. nell’articolo “colour as a mass editorial with the publication of no. 8, the “cultura e scienza del colore color culture and science” journal has completed its fourth year of life. for two years the journal has published only articles in english or bilingual. the ethical code, the peer review process and the detailed instructions for authors are available on the website. each article is indexed by a doi code and for each published article the dates of reception, review and acceptance are declared, in addition to any sources of funding and any conflicts of interest. all of these criteria, with others already introduced for some time, will allow us in the 2018 to start the procedure to request to be included in international indexing databases. the journal is published by a multidisciplinary association that has in the topic of color its point of reference. also in this issue there is a clear example of multidisciplinary integration. michela rossi, maria pompeiana iarossi and giampiero mele, in their paper “ principles and applications. consistency and experimentation in the work of piero bottoni, from the cromatismi to sesto san giovanni”, analyze the work of the architect piero bottoni, through the tools of investigation of the representation, from the “cromatismi” presented at the iii biennial of monza in 1927, to the town hall of sesto san giovanni in the 60s. in the paper “colour quantity contrast in itten’s theory: spectrophotometry for verifying statements”, the authors agapito di tommaso, vincenzo garro, anna maria gueli, sabina martusciello, maria dolores morelli and stefania pasquale, elaborate on the paternity theme of the concept of color quantity contrast of the six primary colors of itten’s theory, through an historical and metrological analysis, starting from schopenhauer’s writings. desirée sabatini, ivano forte, ilma schiavitti, mauro sabatini and alessio pietrini in their research “the recovery of the original colour of the archive material: the digital colour correction of the ancient anti-semitic discourse of the duce in 1938” deal with digital color, illustrating the scientific and methodological assumptions that have been used in the digitalization and restoration of a 1938 film preserved at the archivio storico luce. in the paper “the meanings of the red” anna luana tallarita continues her historical research on red. lynne bartlett in “an overview of the history of the use of color in jewelery” presents an interesting historical analysis of the materials and processing methods used in the creation of jewels from prehistoric times to today. in the article “color as a mass product. designing of the 6 cultura e scienza del colore color culture and science | 08 | 2017 issn 2384-9568 product. designing of the collection of interior paint colours for the polish market”, agata kwiatkowskalubanska, presenta una ricerca sulle palette di colori proposte nel periodo 2011-2013 dai due principali produttori polacchi di vernici, vendute direttamente ai consumatori per il design di interni. infine daria casciani, fulvio musante e maurizio rossi presentano la ricerca “exploring the relationship between leds lighting, urban materials chromaticity and people: measurements, design and evaluation” nell’area del lighting design e metrologia, ponendo in relazione le nuove sorgenti led con i materiali urbani e la valutazione percettiva dei fruitori. nelle rubriche, renata pompas presenta la recensione del libro cromorama di riccardo falcinelli, mentre michela lecca con osvaldo da pos, nella rubrica communications and comments, presentano una dissertazione scientifico bibliografica sulla differenza tra la sensazione cromatica fisiologica e la percezione cromatica cognitiva. editor in chief maurizio rossi interior paint collection for the polish market“, agata kwiatkowska-lubanska, presents a research on the color palettes proposed in the period 20112013 by the two main polish paint producer, sold directly to the consumers for interior design. finally, daria casciani, fulvio musante and maurizio rossi present the research “exploring the relationship between leds lighting, urban materials chromaticity and people: measurements, design and evaluation” in the area of lighting design and metrology, linking the new leds sources with the urban materials and the perceptive evaluation of the users. in the columns, renata pompas presents the review of the book cromorama by riccardo falcinelli, while michela lecca with osvaldo da pos, in the communications and comments column, present a scientific bibliographic dissertation on the difference between the physiological color sensation and the cognitive color perception. editor in chief maurizio rossi cultura e scienza del colore color culture and science 79 cultura e scienza del colore color culture and science | 07 | 2017 | coloumn. communications and comments issn 2384-9568 1michela lecca lecca@fbk.eu 2osvaldo da pos osvaldo.dapos@unipd.it 1fondazione bruno kessler, center for information and communication technology, technologies of vision, trento, italia; 2università degli studi di padova, italia communications and comments in this column, we would like to propose a novel topic, which could be of interest for the wide community of color scholars: a joint analysis of the human color sensation and perception from the view-points of the phycologists, color scientists, literature scholars and artists. in this framework, many issues have to be addressed, first of all the definition of color sensation and color perception. in the following, we report some general considerations and observations that do not pretend to grasp the complex meaning of color sensation/perception, rather they would like to become a starting point of a more detailed discussion among the color scholars and in particular among the members of the gruppo del colore-associazione italiana colore. color sensation and perception are considered subsequent processes of human color vision. nevertheless, these terms are often used improperly, sometimes they are even erroneously employed as synonyms, creating ambiguities and misunderstanding. this confusion is well described by the words of the english philosopher john stuart mill (1806 – 1873), which wrote: “we have a name for the objects which produce in us a certain sensation: the word white. we have a name for the quality of those objects, to which we ascribe the sensation: the name whiteness. but when we speak of the sensation itself […], language, which adapts itself for the most part only to the common uses of life, has provided us with no single-worded or immediate designation” [1]. in 1953, the committee on colorimetry of the optical society of america proposes the following definitions [2]: color sensation is a “mode of mental functioning that is directly associated with stimulation of the organism”, while color perception is a “mode of mental functioning that includes the combination of different sensations and the utilization of past experience in recognizing the objects and facts from which the present stimulation arises.” more recently, in 1988, jonathan c. fish claims [3]: “physiologists have shown that light reflected from a dab of paint and entering the retina of the eye results in the discharge of electrical signals that are transmitted to certain regions of the brain causing the occurrence of colour sensations […]. these sensations are one meaning of the term colour. but since other meanings are commonly given to it, […] it is sometimes helpful to refer to the sensation of colour as psychological colour”. fish clearly states that the expression “color sensation” is often used to indicate both the sensorial stimulation (i.e. color sensation is the result of the propagation of an electrical signal from the eyes to the brain) and its psychophysiological interpretation (i.e. the so-called “psychological color”), dependent on aesthetic issues [4], involving subjective “carpet” by giuseppe ungaretti every color expands and lays on the other colors to be more alone if you look at it. coloumn “tappeto”, giuseppe ungaretti ogni colore si espande e si adagia negli altri colori per essere più solo se lo guardi. “l’allegria da ultime”, milano 1914/1915 80 cultura e scienza del colore color culture and science | 07 | 2017 | lecca m. and da pos o. issn 2384-9568 experience and cultural heritage. the conception that sensation and perception are two very distinct features of our sensory experience is very diffuse: generally, sensation is considered to be more peripheral, local, fragmented, while perception is more central, organized, and global. this idea has entered and is still popular in the anglo-saxon tradition based on helmholtz’s neuropsychological theories [5], stating that visual receptors are linked to the cortex by single neurons, isolated from each other, with the task of bringing peripheral, unmodified information to the cortex. according to helmholtz, the central neuron system would have the task of organizing and interpreting these data, based on past experiences, hypotheses to be verified, mathematical and statistical knowledge, or even on other sensorial information, e.g. tactile sensation. the conclusions are that in the sensory data, ‘local lnformation’ are poor and disorganized, and that perception – which is driven by brain activity is the full stage of organization where objects, events, meanings, etc. appear. a departure from this theory is proposed by gibson [6]: he considers the brain activity fundamental for perception, but he states that all the information needed to perception is already present in the stimulation. an alternative approach to this theory is that the organization responsible for the ‘last stage perception’ does not necessarily require cognitive additions, but derives from its own nervous system operations, dictated above all by genetic components aimed at creating a perceptive phenomenal world, sufficiently simple to make the resultant behaviour fitting the environment. for instance, following the work of hering [7] , color constrast would be a side-to-side inhibitory neural phenomenon instead of a scientific knowledge of colour blends, as proposed by helmholzt. obviously, no interaction between perceptual organization and higher-level cognitive activity is excluded, but these are not necessary [8]. a modern possibility of saving the distinction between sensation and perception is given by katz’s suggestion [9] of evaluating and comparing differently coloured areas by observing them in ‘reduction’ condition. reduced colours are seen through a hole made on a white (or black) screen: in this case, the term reduction means simplifying the context of each coloured area to make it as simple and uniform as possible so that any observed differences cannot depend on the context. since anything we observe always appears to be organized in a basic way according to the figure-background categories, even those that we call sensations appear to be somehow organized, and therefore should be called perceptions. the conclusion is that retaining the original distinction of sensation-perception would only make sense of wanting to insist on the original helmoholtzian theory, unless one understands sensation as a perception in a reduced context. the debate between anglo-saxon and american theories opens the problem to determine which features are captured and/or involved in color sensation and in color perception. retinex theory by edwin h. land and john j. mccann [10] , as well as many studies conducted by the artists of the pointillisme trend and the poetry by giuseppe ungaretti (1888-1970) opening this column, consider spatial information as an element highly relevant to color sensation (and thus to color perception). before retinex, the human color vision system was supposed to catch colors similarly to a camera, in the sense that the human color sensation derived by observing a point in the scene would correlate with the scene reflectances [11]. land and mccann conducted a series of experiments that strongly contradicted this belief, showing that human color vision is a spatial, local process, as illustrated by the simultaneous figure 1: a color chart of healthy fruits and vegetables, adapted from http:// www.rawayurveda.com/4974/eat-arainbow-food-color-chart/ 81 cultura e scienza del colore color culture and science | 07 | 2017 | coloumn. communications and comments issn 2384-9568 contrast (see figure 1). this spatial color interaction is well described by the poetry “tappeto” by ungaretti. he was one of the most important leaders of the literary movement hermeticism, characterized by a concise, piping style reflecting the prostration state of the human soul after the experience of the first world war and fascismus. in “tappeto”, ungaretti describes the color sensation derived by observing a carpet. carpets were for paul gaugin the objects most suitable to study color effects, as he wrote in some scattered notes: “you all, painters, searching for a color techniquelet analyze the carpets and find out all you need” [12]. in “tappeto”, the spatial element influencing the color sensation is the distance at which the single color composing the carpet is viewed: in line with retinex theory, the color sensation at a point changes by enlarging the field of view, thus by changing the locality of the observation with the possible inclusion of more colors. this issue is also at the basis of impressionism, pointillism, and divisionism: these are painting techniques where the objects composing an imaged scene are represented by small brush strokes, with no shading and no color gradient. in particular, pointillism, introduced in 1880s by the painters georges seurat (1859 – 1891) and paul signac (1863 –1935), depicts the observed scene as a set of patterns composed by many small, distinct dots of color. seurat and signac were strongly interested in color science, and their point-based painting technique grounds on the human capability of eyes and mind to blend spatially adjacent color spots, sensing novel tones and shades. on the contrary, anglo-saxon theory negates the presence of distance information in color sensation, and supposes that the depth information mainly comes from other sensorial experiences: brain adds more information from other sources, so that what is seen may appear very different upon the way it is observed. as matter as fact, the considerations reported in this column rely on studies carried out in the 19th and 20th centuries: did the technological novelties of the 21st century change the meaning of color sensation and perception? in case, how? could we still say, as fish, that “colour science and colour art are, for the most part, on separate paths”? what is the feeling of the gruppo del colore? how can its members contribute to clarify the concept of color sensation and perception and to detect the features more relevant to color vision? once again, we think that the complex world of color has been not yet fully investigated and more efforts should be done to achieve a better color understanding: now, we give the floor to the reader. figure 1 simultaneous contrast: the same dachshund looks differently colored when displayed on background with different grey-level intensity (on top). as matter as fact, the dachshund color is constant (on bottom). 82 cultura e scienza del colore color culture and science | 07 | 2017 | lecca m. and da pos o. issn 2384-9568 bibliography and notes [1] mill, john stuart, “a system of logic”, university press of the pacific, honolulu, 2002, isbn 1-4102-0252-6 [2] committee on colorimetry, optical society of america, “the science of color” (crowell, 1953). [3] fish, jonathan c. “colour as sensation in visual art and in science.” leonardo (1981), vol. 14, n. 2, pp. 89-98. [4] from its etymology aesthetics means sensation, from the greek αἴσθησῐς: 1. perception from the senses, feeling, hearing, seeing; 2. perception by the intellect as well as the senses; 3. that which is perceived: scent; 4. ability to perceive: discernment; 5. cognition or discernment of moral discernment in ethical matters (wiktionary.org). therefore there is no great distance between aesthetics and sensation. fish, as most people today, not only considers aesthetics as personal experience (sensation) but also exprression of cultural heritage. [5] pastore, nicholas. “selective history of theories of visual perception 1650–1950”. oxford university press, 1971. [6] gibson, james j. 1979. “the ecological approach to visual perception”. boston: houghton mifflin. [7] hering, ewald, (1888), “über die theorie des simultanen kontrastes von helmholtz”, 4. mitteilung, pflueger archiv, 43, 1-21. [8] dunker karl, “the influence of past experience upon perceptual properties.” american journal of psychology, 1939, 52, 255-265 [9] katz, david. 1911. “die erscheinungsweisen der farben und ihre beeinfluss durch die individuelle erfahrung. “leipzig: barth. [10] land, edwin h., and john j. mccann. “lightness and retinex theory.” josa 61, no. 1 (1971): 1-11. [11] “of course the eye behaves in a completely different way from a camera, as it must move continuously to perceive anything, while the camera can catch the light and form a sharp image only if it is steady, condition which eliminates all visual perception.” (a. l. yarbus, eye movements and vision. new york: plenum press, 1967. translated from russian by basil haigh. original russian edition published for the institute of information transmission of the academy of sciences of the ussr by nauka press in moscow in 1965). [12] gauguin, paul. “diverses choses (1896-1898)”, ouvres, paris 1974, p.178. cultura e scienza del colore color culture and science 09 18 riv is ta s em es tr al e | h al fye ar ly jo ur na l | d o i: 10 .2 37 38 /c c sj .0 0 rivista dell’associazione italiana colore www.gruppodelcolore.it doi: 10.23738/ccsj.i92018.00 cultura e scienza del colore color culture and science 09numero 09 maggio 2018 number 09 may 2018cultura e scienza del colorecolor culture and science rivista semestrale dell’associazione italiana colore http://jcolore.gruppodelcolore.it/ issn 2384-9568 doi: 10.23738/ccsj.00 ance e227716 direttore responsabile | editor-in-chief maurizio rossi (politecnico di milano, it) redazione | associate editors aldo bottoli (b&b colordesign, it) daria casciani (politecnico di milano, it) marco gaiani (università di bologna, it) silvia piardi (politecnico di milano, it) alessandro rizzi | deputy editor (università degli studi di milano, it) francesca valan (studio valan, it) editorial board members john barbur (city university london, uk) giovanni bartolozzi (ifaccnr, it) berit bergstrom (ncs colour ab, se) giulio bertagna (b&b colordesign, it) janet best (natific, uk) aldo bottoli (b&b colordesign, it) patrick callet (école centrale paris, fr) jean-luc capron (université catholique de louvain, be) daria casciani (politecnico di milano, it) osvaldo da pos (università degli studi di padova, it) hélène declermont-gallernade (chanel parfum beauté, fr) reiner eschbach (xerox, usa) alessandro farini (ino-cnr, it) christine fernandez-maloigne (university of poitiers, fr) renato figini (konica-minolta sensing europe, eu) raffaella fontana (ino-cnr, it) davide gadia (università degli studi di milano, it) marco gaiani (alma mater studiorum università di bologna, it) robert hirschler (serviço nacional de aprendizagem industrial, br) sandra krasovec (fashion institute of technology, usa) francisco imai (canon, usa) lia luzzatto (color and colors, it) kevin mansfield (ucl, uk) veronica marchiafava (gdc-associazione italiana colore, it) gabriel marcu (apple, usa) cultura e scienza del colore color culture and science rivista dell’associazione italiana colore registrazione presso il tribunale di milano al n. 233 del 24.06.2014 anna marotta (politecnico di torino, it) manuel melgosa (universidad de granada, es) anna grazia mignani (ifac-cnr, it) annie mollard-desfour (cnrs, fr) maria luisa musso (universidad de buenos aires, ra) galina paramei (liverpool hope university, uk) laurence pauliac (historienne de l’art et de l’architecture, paris, fr) silvia piardi (politecnico di milano, it) marcello picollo (ifac-cnr, it) renata pompas (afol milano-moda, it) boris pretzel (victoria & albert museum, uk) noel richard (university of poitiers, fr) katia ripamonti (cambridge research system, uk) alessandro rizzi (università degli studi di milano, it) maurizio rossi (politecnico di milano, it) jodi l. sandford (università di perugia, it) raimondo schettini (università degli studi di milano bicocca, it) verena m. schindler (chair aic s.g. environmental colour design) gabriele simone (renesas electronics europe gmbh, de) andrea siniscalco (politecnico di milano, it) ferenc szabó (university of pannonia, hu) mari uusküla (tallinn university, ee) francesca valan (studio valan, it) ralf weber (technische universität dresden, de) alexander wilkie (charles university in prague, cz) peer review process tutti gli articoli inviati alla rivista “cultura e scienza del colore color culture and science” sono sottoposti ad un processo di revisione secondo la seguente procedura: prima revisione gli associate editor valutano ogni articolo per determinare se il tema e il contenuto sono di interesse per la rivista. una volta valutati gli articoli, gli associate editor selezionano dei revisori scegliendoli nell’editorial board in base all’esperienza degli stessi in un particolare settore disciplinare o tematica. seconda revisione ogni articolo è revisionato da due o tre revisori in un processo in cui essi stessi e gli autori sono mantenuti anonimi. ai revisori è chiesto di valutare l’articolo considerando la sua originalità, la metodologia applicata e l’impatto sulla ricerca o sulla pratica professionale. dopo aver raccolto i commenti dei revisori, gli associate editor elaborano e inviano al direttore responsabile un giudizio riassuntivo sull’accettazione o meno dell’articolo. collaboratori | contributors ingrid calvo ivanovic, osvaldo da pos, martin eessalu, gabriele gianini, gianluca guarini, michela lecca, anna mazzanti, laurence pauliac, alessandro rizzi, maria elisabetta ruggiero, andrea siniscalco, mari uusküla editore | publisher gruppo del colore – associazione italiana colore www.gruppodelcolore.it sede legale: piazza carlo caneva, 4 20154 milano (italia) all articles submitted to “cultura e scienza del colore color culture and science” journal are peer-reviewed according to the following procedure: first review the associate editors evaluate each article in order to define if the topic and content is suitable for consideration by the journal. once the article passes the initial review, the associate editors select several referees in the editorial board based on their expertise in the particular field or topic. second review each article is reviewed by two or three referees under a double-blind peer review process where the authors and the reviewers are kept anonymous. referees are asked to evaluate the manuscript based on its originality, methodology and impact to research and relevance to the professional practice. after collecting the referees’ reports, the associate editors make a recommendation on the acceptability of the article to the editor in chief. doi: 10.23738/ccsj.i92018.00 gruppo del colore associazione italiana colore sommario | summary english | italian 09 5 7 17 29 39 45 55 65 74 79 editorial by maurizio rossi the colour in ships: communication and identity il colore nei mezzi navali: comunicazione ed identità by maria elisabetta ruggiero the contribution of colour in the artistic representation of the sacred. international symbolism between the nineteenth and twentieth centuries l’apporto del colore nella rappresentazione artistica del sacro. simbolismo internazionale fra otto e novecento by anna mazzanti restorations of the monumental polychromy of the gothic cathedrals undertaken by viollet-le-duc by laurence pauliac glossy black is not actually ‘black’: evidence from psycholinguistic colour-naming studies in 14 european languages by mari uusküla and martin eessalu digital visualization of a luminaire: from blueprint to photorealistic representation by andrea siniscalco and gianluca guarini review and comparison of random spray retinex and of its variants stress and qbrix by michela lecca, alessandro rizzi, gabriele gianini symbolic color associations in goethe’s farbenlehre and its application in the pictorial work of its early receptors by ingrid calvo ivanovic communications and comments by michela lecca and osvaldo da pos claudio oleari memorial by gruppo del colore – associazione italiana colore coloumn english 4 cultura e scienza del colore color culture and science | 09 | 2018 issn 2384-9568 this page has been intentionally left white 5 cultura e scienza del colore color culture and science | 09 | 2018 issn 2384-9568 con il n.9, la rivista “cultura e scienza del colore color culture and science” ha raggiunto il suo quinto anno di vita. al fine di internazionalizzarne la diffusione, dal 2015, la rivista pubblica solo articoli in lingua inglese o bilingue. abbiamo introdotto da tempo questi criteri perché nel febbraio 2018 abbiamo inviato a clarivate analytics la domanda per essere inseriti nell’emergins sources of citation index (esci) di web of science (wos). la rivista è edita da una associazione no profit che vede nel tema multidisciplinare del colore il suo punto di riferimento. al fine di consentirne una valorizzazione a livello internazionale di ampio respiro, nell’assemblea ordinaria del 19 aprile 2018, i soci hanno deciso che entro la fine di quest’anno la rivista sarà ceduta ad un ente o editore internazionale, con la condizione di mantenerne inalterati i contenuti scientifici e culturali, il titolo, l’issn e la maggior parte del board di redazione. in questo numero abbiamo come sempre contenuti multidisciplinari. maria elisabetta ruggiero, nell’articolo “il colore nei mezzi navali: comunicazione ed identità” analizza, tramite gli strumenti di indagine della rappresentazione, la funzione della componente cromatica nell’ambito delle livree navali e la rispettiva evoluzione storica. nell’articolo “l’apporto del colore nella rappresentazione artistica del sacro. simbolismo internazionale fra otto e novecento”, anna mazzanti, tramite un’approfondita analisi storica, approfondisce il tema del colore, che assume un valore simbolico, nell’ambito della pittura sacra a cavallo tra il diciannovesimo e il ventesimo secolo. laurence pauliac in “restorations of the monumental polychromy of the gothic cathedrals undertaken by viollet-leduc” , presenta un’interessante analisi critica, per i soli aspetti inerenti il colore, dell’attività di restauro condotta nel diciannovesimo secolo dall’architetto e restauratore francese eugène emmanuel viollet-le-duc nella cattedrale di notre-dame di parigi. in “glossy black is not actually ‘black’: evidence from psycholinguistic colour-naming studies in 14 european languages”, mari uusküla e martin eessalu, presentano una ricerca interculturale nell’area del color naming prendendo in considerazione non solo gli aspetti inerenti tinta, saturazione e chiarezza, ma anche la lucidità del campione di materiale considerato: in questo caso il nero. andrea siniscalco e gianluca guarini, nel saggio “digital visualization of a luminaire: editorial with the 9th issue, the “ cultura e scienza del colore color culture and science” journal reached its fifth year of life. in order to internationalize its dissemination, the magazine has been publishing only articles in english language or bilingual since 2015. we have established these criteria for three years because in february 2018 we sent the application to be included in the emergins sources of citation index (esci) of web of science (wos) to clarivate analytics. the journal is published by a nonprofit association that has its reference point in the multidisciplinary theme of color. in order to allow a wide-ranging international appreciation, in the ordinary meeting of april 19th 2018 the members of the association decided that by the end of this year the journal will be transfer to an international organization or publisher, with the condition to maintain unaltered its scientific and cultural content, its title, its issn and most of its editorial board. in this issue, as always, there are multidisciplinary contents. maria elisabetta ruggiero analyzes in the article “the colour in ships: communication and identity” the function of the chromatic component within the naval liveries and its historical evolution, through the tools of study of the representation. in the essay “the contribution of colour in the artistic representation of the sacred. international symbolism between the nineteenth and twentieth centuries”, through a historical analysis, anna mazzanti delves into the theme of color, that assumes a symbolic value, in the context of the sacred painting between the nineteenth and twentieth centuries. laurence pauliac in “restorations of the monumental polychromy of the gothic cathedrals undertaken by viollet-le-duc” presents an interesting critical analysis, only for the aspects concerning color, of the restoration activity carried out in the nineteenth century by the french architect and restorer eugène emmanuel viollet-le-duc in the cathedral of notre-dame in paris. in “glossy black is not actually ‘black’: evidence from psycholinguistic colour-naming studies in 14 european languages “, mari uusküla and martin eessalu present an intercultural research in the area of color naming taking into consideration not only the aspects relating to tint, saturation and clarity, but also the lucidity of the sample of the considered material: in this case the black color. andrea siniscalco and gianluca guarini, in the essay “digital visualization of a luminaire: from blueprint to photorealistic representation”, face 6 cultura e scienza del colore color culture and science | 09 | 2018 issn 2384-9568 from blueprint to photorealistic representation” affrontano un problema ben noto nell’ambito del lighting design: le tecniche di rappresentazione degli apparecchi di illuminazione nei rendering fotorealistici dei progetti di illuminazione. in “review and comparison of random spray retinex and of its variants stress and qbrix”, michela lecca, alessandro rizzi e gabriele gianini, nell’ambito del colore digitale, presentano una rassegna e confronto di tre algoritmi di retinex utilizzabili nell’ambito dell’equalizzazione cromatica delle immagini. infine ingrid calvo ivanovic, in “symbolic color associations in goethe’s farbenlehre and its application in the pictorial work of its early receptors”, presenta un’interessante analisi nell’ambito della cultura del colore, in merito ai contributi teorici di johann wolfgang goethe in relazione agli aspetti simbolici del colore nell’ambito della pratica pittorica. nella rubrica, communications and comments, michela lecca con osvaldo da pos proseguono la dissertazione scientifico bibliografica sulla sensazione cromatica fisiologica e la percezione cromatica cognitiva, introducendo anche gli aspetti culturali e sociali legati al colore dato che questi influenzano la percezione cognitiva. il direttore responsabile maurizio rossi a well-known problem in the field of lighting design: the representation techniques of lighting fixtures in the photorealistic renderings of lighting projects. in “review and comparison of random spray retinex and of its variants stress and qbrix”, michela lecca, alessandro rizzi and gabriele gianini, in the field of digital color, present a review and comparison of three retinex algorithms that can be used in the color equalization of the images. finally, ingrid calvo ivanovic, in “symbolic color associations in goethe’s farbenlehre and its application in the pictorial work of its early receptors”,presents an interesting analysis in the context of color culture, regarding the theoretical contributions of johann wolfgang goethe in relation to the symbolic aspects of color in the context of pictorial practice. in the column, communications and comments, michela lecca with osvaldo da pos continue the scientific bibliographic dissertation on the physiological chromatic sensation and on the cognitive chromatic perception, introducing also the cultural and social aspects related to color as these influence cognitive aspects. the editor in chief maurizio rossi cultura e scienza del colore color culture and science 23 cultura e scienza del colore color culture and science | 08 | 2017 issn 2384-9568 colour quantity contrast in itten’s theory: spectrophotometry for verifying statements abstract colour quantity contrast originates from the quantitative ratio of two or more colours and no color stands out more than another if such report is balanced. considering how the intensity parameter, defined as the brightness refers to a gray background of medium brightness, the values of the mutual relations between primary and secondary colours of subtractive synthesis: yellow: purple: blue: orange: red: green, reported by itten that are attributed to goethe are in order: 9:8:6:3:4:6. it is worth mentioning in this context that a detailed research on this matter leaves rather suppose that the authorship of these values is attributed to schopenhauer. he however did not base its considerations on the intensity but the amount of energy that reaches the retina of the viewer. the study had as main objective the verification of this statement concerning the relationship between the three primary and three secondary subtractive synthesis colours through the specification of the colour using the spectrophotometric method. the results have confirmed what was expected in terms of quality of performance values of mutual relations of the six colours but showed a quantitative difference than the sestina, 9:8:6:3:4:6, reported by itten. keywords colour, colour quantity contrast, colour contrast, itten, schopenhauer, complementary colours citation: di tommaso a., garro v., gueli a. m., martusciello s., morelli m. d., pasquale s. (2017) ‘colour quantity contrast in itten’s theory: spectrophotometry for verifying statements’, cultura e scienza del colore color culture and science journal, 08, pp. 23-34, doi: 10.23738/ccsj.i82017.02 received 7 july 2017; revised 20 october 2017; accepted 13 november 2017 agapito di tommaso was director of several european packaging printing industries. now he is colour consultant and his research activity includes a new bottom-up approach in colour matching methodology. vincenzo garro is a junior research fellow in applied physics at catania university. his research activity is aimed to the characterization of historical pigments pure and in mixtures through spectrophotometric and colorimetric analysis and using raman spectrometry. anna maria gueli is a professor in applied physics at the university of catania and the head of ph3dra (physics for dating diagnostics dosimetry research and applications) laboratories included in the european research infrastructure for heritage science through infn cultural heritage network (chnet). her research interests include interdisciplinary approaches to colour-difference evaluation and applied colorimetry starting from optical properties of materials. maria dolores morelli is a research professor of design, department of architecture and industrial design, university of campania “luigi vanvitelli”, italy. scientific director the project of applied research landesign® and the international master “landesign/ali-ment-azione/ diaeta mediterranea”; scientific member of “benecon scarl cultural heritage, economy, design”. eight international international awards received, including the mention premio adi compasso d’oro international awards 2015 “design for food and local heritage”. sabina martusciello is an associate professor of design, department of architecture and industrial design, university of campania “luigi vanvitelli”, italy.dean “design and comunication” degree course; scientific director the project of applied research landesign®; director the international master “landesign/ali-ment-azione/diaeta mediterranea”; board of directions “benecon scarl cultural heritage, economy, design”. eight international international awards received, including the mention premio adi compasso d’oro international awards 2015 “design for food and local heritage”. stefania pasquale is a research fellow in “diagnostics for characterisation and dating of archaeomaterials in cultural heritage and chnet iperion ch.it/e-rihs networks” at national institute for nuclear physics in catania. she received a master degree in sciences for conservation and restoration of cultural heritage from parma university in 2011. her research interests are colour science for polychrome works of art characterisation. 1agapito di tommaso info@persud.org 2vincenzo garro enzogarro89@gmail.com 2anna maria gueli agueli@unict.it 3sabina martusciello sabina.martusciello@ unicampania.it 3maria dolores morelli mariadolores.morelli@ unicampania.it 2stefania pasquale stefania.pasquale@ct.infn.it 1aps p.e.r.sud 2ph3dra labs (physics for dating diagnostics dosimetry research and applications), dipartimento di fisica e astronomia, università di catania & infn sez. catania 3laboratorio landesign®, dipartimento di architettura e disegno industriale, seconda università degli studi di napoli, benecon scarl sun, unina, unisa, unisannio italian translation provided: il contrasto di quantità nella teoria di itten: la spettrofotometria per la verifica degli enunciati 24 cultura e scienza del colore color culture and science | 08 | 2017 | 23 -34 di tommaso a. et al. issn 2384-9568 doi: 10.23738/ccsj.i82017.02 1. introduction the colour quantity contrast theory is born from the reciprocal quantitative relationship among two or more colours and it is generally attributed to goethe. itten himself fostered this idea attributing him the authorship. johannes itten, in his book “the art of color” (itten, 1997), described in detail the seven contrasts existing between colours. the last one was the quantity contrast that arose from the reciprocal quantitative relationship between two or more colours. according to itten, two factors determined the effect of a colour: its luminous intensity and the size of the colour field. because itten was not able to measure these two parameters, especially the first one, in the absence of appropriate instruments, the only way to evaluate them was to compare them to a neutral background of medium luminosity. referring to the studies carried out by goethe, itten reported a numerical scale of easy-touse light values. however, he admitted that the hypothesized values were only approximate, relying only on the observing eye, even if adequately trained. the values of the reciprocal relationships of colour brightness, according to itten, would have been the following: according to itten, “to translate the brightness values in harmonious values of quantity, the numeric ratio has to be inverted: so, yellow, for example, being three times brighter, should have a surface three times smaller than his complementary violet colour” (itten, 1997). from this perspective, the quantity relationships available for complementary colours are the following: and so the harmonious proportion of the primary and secondary colours are: the figure 1(a) shows itten’s chromatic reel with twelve colours, the figure 1(b) the same reel in which the surfaces of primary and secondary colours are illustrated with the respective harmonious quantity values; in figure 1(c) the yellow : orange : red : violet : blue : green 9 : 8 : 6 : 3 : 4 : 6 yellow : violet = 1/4 : 3/4 orange : blue = 1/3 : 2/3 red : green = 1/2 :1/2 yellow : orange : red : violet : blue : green 3 : 4 : 6 : 9 : 8 : 6 1. introduzione la teoria del contrasto di quantità nasce dal reciproco rapporto quantitativo tra due o più colori ed è generalmente attribuita a goethe. lo stesso itten ha alimentato questa idea, attribuendogliene la paternità. nel suo libro arte del colore johannes itten (itten, 1997) descriveva dettagliatamente i sette contrasti esistenti tra i colori. l’ultimo era, appunto, il contrasto di quantità che nasceva dal reciproco rapporto quantitativo tra due o più colori. secondo itten due fattori determinavano l’effetto di un colore: la sua intensità luminosa e le dimensioni del campo colorato. non potendo misurare i due parametri indicati, specialmente il primo, in assenza di strumentazioni idonee, l’unico modo per poterli valutare era quello di confrontarli tra loro su di uno sfondo neutro di media luminosità. riferendosi agli studi effettuati da goethe, itten riportava una scala numerica dei valori di luminosità di uso molto semplice, pur ammettendo che i valori ipotizzati erano solo approssimativi dovendo sempre affidarsi solo all’occhio dell’osservatore, quantunque adeguatamente educato. i valori dei rapporti reciproci della luminosità dei colori, secondo itten, sarebbero stati dunque, nell’ordine, i seguenti: secondo quanto sosteneva itten, “per tradurre i valori di luminosità in valori armonici di quantità, i rapporti numerici vanno invertiti: cioè, il giallo ad esempio essendo tre volte più luminoso dovrebbe occupare una superficie tre volte più piccola del suo complementare viola” (itten, 1997). in tale ottica, i rapporti di quantità validi per i complementari sono i seguenti: e pertanto le proporzioni armoniche dei colori primari e secondari sono: nella figura 1(a) è riportato la prima ruota cromatica di itten a dodici colori; nella figura 1(b) si osserva la stessa ruota in cui le superfici dei soli sei colori primari e secondari sono illustrati con i rispettivi valori armonici di quantità; in giallo : arancio : rosso : viola : blu : verde 9 : 8 : 6 : 3 : 4 : 6 giallo : viola = 1/4 : 3/4 arancio : blu = 1/3 : 2/3 rosso : verde = 1/2 :1/2 giallo : arancio : rosso : viola : blu : verde 3 : 4 : 6 : 9 : 8 : 6 25 cultura e scienza del colore color culture and science | 08 | 2017 | 23 -34 colour quantity contrast in itten’s theory: spectrophotometry for verifying statements issn 2384-9568 relationships between the harmonious values and the related complementary ones are presented. according to itten, once established the proportions illustrated in figure 1c, the harmonious quantity created an effect of stasis and quiet. this research starts from some studies conducted by schopenhauer in which he presented his theory concerning the relative relationships between colours. after a critical review of the itten hypothesis, the goal of this work is the experimental checking of the colour quantity contrast according to schopenhauer’s theory. the colour specification through spectrophotometric analysis simulates the visual perception of the human eye (actio retinae). for this reason, the measurements were carried out with this methodology on the samples prepared ad hoc. the samples were designed to calculate the harmonious quantity values of the six primary and secondary colours of the subtractive synthesis for performing the comparison with the values attributing to them both by itten and schopenhauer. in the following paragraphs, the research’s successive steps will be described. first, in paragraph 2, the statements representing figure 1 (a) itten’s chromatic disc; (b) itten’s disc with the harmonious quantity values; (c) relationships between the harmonious values and the related complementary ones. figura 1 (a) disco cromatico di itten; (b) disco di itten con i valori armonici di quantità; (c) rapporti tra i valori armonici dei complementari abbinati figura 1(c) sono indicati i rapporti tra i valori armonici esistenti dei complementari abbinati. itten affermava che i rapporti armonici, una volta stabilite le proporzioni illustrate in figura 1c , creavano un effetto di stasi e di quiete. il presente lavoro prende spunto da alcuni studi di schopenhauer dedicati al colore in cui è presente la teoria da questi formulata, in epoca precedente ad itten, sui rapporti relativi tra i colori. dopo aver valutato criticamente l’ipotesi di itten, obiettivo della ricerca è stato la verifica sperimentale del contrasto di quantità secondo la formulazione di schopenhauer. considerato che la specificazione del colore tramite il metodo spettrofotometrico a contatto simula il processo di percezione visiva dell’occhio (actio retinae), le misure sono state realizzate con questa metodologia su campioni appositamente preparati. tali campioni sono stati realizzati al fine di calcolare i valori armonici di quantità di sei colori primari e secondari della sintesi sottrattiva per poi eseguire il confronto con i valori loro attribuiti tanto da itten quanto da schopenhauer. i paragrafi che seguono descriveranno tutte le fasi del lavoro di ricerca. dapprima, nel paragrafo 2, verrà analizzato l’enunciato che rappresenta la base teorica del presente lavoro. successivamente, verrà presentato il modus operandi nella preparazione dei campioni b) c) a) 26 cultura e scienza del colore color culture and science | 08 | 2017 | 23 -34 di tommaso a. et al. issn 2384-9568 doi: 10.23738/ccsj.i82017.02 the theoretical basis of the work will be analysed. then, the sample preparation and the spectrophotometric method respectively will be presented in paragraphs 3.1 and 3.2. the results will be discussed in paragraph 4 while the conclusions and perspectives of the work will be summarized in paragraph 5. 2. the analysis of the statements without prejudice regarding the importance of itten’s theory on the seven colour contrasts, this study is focused on a hypothesis of authorship of the statement on the contrast of a quantity different to itten’s one. there is no evidence in goethe’s works about colour of the reciprocal relationships and the series attributed to him by itten. also goethe’s table, representing the colour reel with surfaces and parity ratios between them, confirms what has been highlighted so far (goethe, 1997). starting from the hypothesis that itten’s theory of quantity contrast could not be attributable to goethe, it is permissible to inquire into the authorship of the statement. the answer is, in our opinion, in the schopenhauer work. in fact, in the first edition, in latin, of his writings (schopenhauer, 1830), the young german philosopher, probably taking a cue from aristotle (giannantoni, 1973), describes in detail the relationships between the primary and the secondary colours as following: “…ruber igitur cum viridi colore illius actionis sunt exacte dimidiatae: ejiusdem vero duas tertias exhibit aurantiacus; coeruleus autem, utpote hujus complementum, tertiam duntaxat: flavus denique tres quartas, et proinde complementus ejus, violaceus color, quartam modo partem…”. in the edition of 1859 (schopenhauer, 2002) schopenhauer, sustaining his thesis, inserted a schema in which, in addition to black and white, corresponding respectively to the 0 and 1 values, the relationships among the hues were: an eminent confirmation of what has been observed can be found in rudolph arnheim (arnheim, 2005), who faithfully reports the schema, clearly attributing to schopenhauer the authorship of statement. also renato troncon, curator of the italian edition of the “theory of colours” of goethe (goethe, 1987) black 0 violet : yellow = 1/4 : 3/4 cyan : orange = 1/3 : 2/3 green : red = 1/2 :1/2 white 1 analizzati e quindi il metodo spettrofotometrico a contatto, rispettivamente nei paragrafi 3.1 e 3.2. i risultati verranno discussi nel paragrafo 4, mentre le conclusioni e le prospettive del lavoro verranno presentate nel paragrafo 5. 2. analisi degli enunciati fermo restando l’importanza della teoria di itten sui sette contrasti dei colori, questo studio riporta l’attenzione su un’ipotesi di paternità dell’enunciato sul contrasto di quantità diversa da quella formulata da itten. in nessuno degli scritti di goethe dedicati al colore si trova evidenza dei rapporti reciproci e della serie attribuitagli da itten. anche la tavola di goethe, rappresentativa della ruota dei colori a noi pervenuta con superfici e rapporti paritetici tra loro, conferma quanto fin qui evidenziato (goethe, 1997). partendo dall’ipotesi che la teoria di itten del contrasto di quantità possa non essere attribuibile a goethe, è lecito interrogarsi sulla paternità dell’enunciato. la risposta si trova, a nostro avviso, nell’opera di schopenhauer. infatti nella prima edizione in latino di alcuni suoi scritti (schopenhauer, 1830), il giovane filosofo tedesco prendendo probabilmente spunto da aristotele (giannantoni, 1973), descriveva dettagliatamente il rapporto esistente tra colori primari e secondari come segue: “…ruber igitur cum viridi colore illius actionis sunt exacte dimidiatae: ejiusdem vero duas tertias exhibit aurantiacus;coeruleus autem, utpote hujus complementum, tertiam duntaxat: flavus denique tres quartas, et proinde complementus ejus, violaceus color, quartam modo partem…”. nella seguente edizione del 1859 (schopenhauer, 2002), schopenhauer, a supporto della sua ipotesi, inseriva uno schema in cui, con l’aggiunta degli estremi del nero e del bianco, a cui faceva corrispondere rispettivamente i valori 0 ed 1, i rapporti tra le tinte erano: un’autorevole conferma di quanto fin qui osservato, la ritroviamo in rudolph arnheim (arnheim, 2005) che riporta fedelmente questo schema, attribuendo esplicitamente a schopenhauer la paternità dell’enunciato. d’altra parte, anche renato troncon, curatore dell’edizione italiana della “teoria dei colori” di nero 0 violetto : giallo = 1/4 : 3/4 azzurro : arancione = 1/3 : 2/3 verde : rosso = 1/2 :1/2 bianco 1 27 cultura e scienza del colore color culture and science | 08 | 2017 | 23 -34 colour quantity contrast in itten’s theory: spectrophotometry for verifying statements issn 2384-9568 said: “la concezione di itten presenta tuttavia un motivo che non è di origine goethiana ma va fatto risalire a schopenhauer”. after an accurate analysis of the schema previously exposed, a detail, not reported by itten, important for the experimental check of the colour quantity contrast, was found. in the schema, in fact, not only the six primary and secondary colours of subtractive synthesis are described but also the black and white not as colours but as “limits” (schopenhauer, 2002). furthermore, this schema compares the retinal action of each colour respect to its complementary one and with respect to black, supposing its zero value. schopenhauer (schopenhauer, 2002) himself stated that “the precision of the fractions discovered by me..is..intuitive; remains subject of immediate judgment, and it has to be assumed as evident in itself; it is in fact difficult and perhaps impossible, to demonstrate it”. schopenhauer, in fact, did not have the technical instrument suitable to make the measurements and he formulated his statement on visual observation of each colour. instead, today, we have the skills and the instruments allowing us to accurately study this field. therefore, in this research work, the goal is to experimentally verify the schema suggested by schopenhauer. 3. materials and methods 3.1 the analysed samples in order to check on a wide set of materials the effectiveness of our thesis, two different categories of samples of six primary (yellow, magenta, cyan) and secondary (orange, violet and green) hues of subtractive synthesis have been prepared. liquitex ink, lefranc&burgeois flasche and maimeri acrylic and van dyck ferrario and maimeri oil industrial products belong to the first category. they were painted on a hardbound support acrylic pad galeria of winsor &newton 300 g/m2. the only acrylic maimeri was diluted with 20% in weight of water, while both two oils (van dyck ferrario and maimeri) were diluted with 20% in weight of oil. each colour was painted with three coats with a brush of natural bristle directly on hardbound support without any preparation. with the same aim, the second category of goethe (goethe, 1987), afferma: “la concezione di itten presenta tuttavia un motivo che non è di origine goethiana ma va fatto risalire a schopenhauer”. in seguito ad un’accurata analisi dello schema precedente riportato, si è notato un particolare, non riferito da itten, di fondamentale importanza ai fini della verifica sperimentale del contrasto di quantità. nello schema, infatti, sono riportati non solo i sei colori primari e secondari della sintesi sottrattiva, ma anche il nero ed il bianco, non in quanto colori ma come paletti di confine (schopenhauer, 2002). tale schema, inoltre, mette a confronto l’azione sulla retina di ogni colore rispetto a al suo complementare e rispetto a quella del nero, ipotizzata di valore zero. lo stesso schopenhauer (schopenhauer, 2002) affermava che “l’esattezza delle frazioni da me scoperte...è...intuitiva; rimane oggetto del giudizio immediato e deve essere assunta come evidente di per sé; è infatti difficile, e forse impossibile, dimostrarla”. a quei tempi, infatti, non si disponeva degli strumenti tecnici idonei alla misurazione ed egli formulò il suo enunciato sulla base della sola osservazione visiva di ogni colore. oggi, invece, disponiamo di competenze e strumentazione che consentono di effettuare con precisione questa indagine. in questo studio proponiamo, pertanto, una procedura applicativa per verificare lo schema suggerito da schopenhauer. 3. materiali e metodi 3.1 i campioni analizzati ai fini di valutare su un ampio spettro di materiali la validità della tesi sostenuta, sono stati realizzati due differenti macrocategorie di campioni delle sei tinte primarie (giallo, magenta e ciano) e secondarie (arancio, viola e verde) della sintesi sottrattiva. tutti i secondari sono stati ottenuti dalla miscela in rapporto 50:50 in peso dei relativi primari. alla prima categoria appartengono i prodotti industriali acrilici, nello specifico, liquitex ink, lefranc&burgeois flasche e maimeri e i prodotti ad olio, in particolare, van dyck ferrario e maimeri. essi sono stati stesi su un supporto cartonato acrylic pad galeria della windsor &newton da 300 g/m2. l’acrilico maimeri è stato diluito con 20% in peso di acqua, mentre i due oli (van dyck ferrario e maimeri) con 20% in peso di olio. la stesura del colore è avvenuta mediante 28 cultura e scienza del colore color culture and science | 08 | 2017 | 23 -34 di tommaso a. et al. issn 2384-9568 doi: 10.23738/ccsj.i82017.02 samples was realized through powdered pigments. the primary pigments used by itten were: ultramarine blue (codex cts 0561), cinnabar (codex cts 0607) and zinc yellow (codex cts 0557) (cts site, 2017). in this type of samples, for blue ones, specific quantity of green pigment (emerald green), for yellow ones, of red pigment (cinnabar), was added. the pigments, after mixing with vehicle, in ratio 1:3 (pigment:vehicle) were painted on support prepared by zecchi (codex zecchi 4700) (zecchi site, 2017). the employed vehicle was the casein (matteini, 2004), a phosphoprotein obtained from milk in the form of colloidal dispersion, (codex zecchi 2050) (zecchi site, 2017). the goal was to obtain samples having, in terms of colour coordinates, the theoretical values of cielab hues (oleari, 2008). for example, the blue was obtained such as to have a* coordinate equal to zero and the value of b* negative as high as possible. in total, thirty-six samples were obtained: six yellow paintings, six orange, six violet, six cyan, six green respectively for three types of vehicles: acrylic, oil and casein. 3.2 the spectrophotometric analysis the spectrophotometric analysis was carried out in two laboratories: ph3dra (physics for dating diagnostics dosimetry research and applications) labs of the catania university and benecon labs of napoli university. in both laboratories, the analysis were performed by konica minolta spectrophotometer, cm 2600d model, with measurement geometry d/8°, selecting an area of 6 mm in diameter (sav, small average value) following a specific standard protocol (burrafato, 2005). the results are related to the d65 illuminant and the cie 1931 standard colorimetric observer (2° standard observer). it is normally used for the printing colour quality control. data were obtained from repeated measurements (5 different acquisitions) and the elaboration regarded spex/100 values (specular component excluded and uv included). the acquisition were made using software spectramagic® (konica minolta site, 2017) and the data were elaborated with the origin® software (originlab site, 2017). the scale adjustment represents a very important step (gueli, 2014) and it was performed using the white calibration plate (cm-a145) as a target for the maximum lightness and the device cm-a32 for the minimum lightness. the results were elaborated focusing the spectral reflectance factor (srf%) trend in the visible region and the colour cielab coordinates (oleari, 2008). the total uncertainty associated with each measurement was calculated according to the tre passaggi con pennello in setola naturale direttamente su cartoncino senza preparazione. la seconda categoria di campioni è stata realizzata mediante pigmenti in polvere sempre con lo stesso obiettivo. i pigmenti primari di itten utilizzati sono: blu oltremare (codice cts 0561), cinabro (codice cts 0607) e giallo di zinco (codice cts 0557) (cts site, 2017). questi, ad eccezione del rosso, sono stati corretti con quantità note di pigmento verde (verde smeraldo), per il blu e di pigmento rosso (cinabro), per il giallo. i pigmenti, mediante la miscelazione con il legante, in rapporto 1:3 (pigmento:legante) sono stati stesi su tele preparate con gesso (codice zecchi 4700) (zecchi site, 2017). il legante utilizzato è la caseina (matteini, 2004), una fosfoproteina ottenuta dal latte in forma di dispersione colloidale, usato fin dai tempi antichi (codice zecchi 2050) (zecchi site, 2017). il fine è quello di ottenere dei campioni che rispecchino, in coordinate cromatiche, i valori teorici delle singole tinte per il sistema cielab (oleari, 2008). il blu, ad esempio, è stato ottenuto in modo tale da avere coordinata a* nulla ed il più alto valore possibile di b* (negativo). in totale, sono stati ottenuti trentasei campioni: sei campiture gialle, sei arancioni, sei magenta, sei viola, sei ciano e sei verdi rispettivamente per i tre tipi di legante: acrilico, olio e caseina. 3.2 le misure spetrofotometriche le misure spettrofotometriche sono state eseguite presso due laboratori: i laboratori ph3dra (physics for dating diagnostics dosimetry research and applications) dell’università degli studi di catania e quelli della benecon dell’università degli studi di napoli. in entrambi i laboratori, le analisi sono state condotte tramite spettrofotometro konica minolta, modello cm2600d con geometria d/8°, selezionando un’area di misura di diametro 6 mm (maschera small average value, sav) e seguendo un preciso standard di laboratorio (burrafato, 2005). per l’esecuzione delle misure, è stato selezionato l’illuminante d65 e l’osservatore standard 2° del 1931 che è solitamente usato per la valutazione del colore nei controlli di qualità di stampa. per ogni campione sono state fatte cinque acquisizioni mediante il software spectramagic® (konica minolta site, 2017) e i dati sono stati elaborati con il software origin® (originlab site, 2017). le elaborazioni hanno riguardato i valori spex/100 (specular component excluded and uv included). l’adjustment della scala rappresenta uno step di fondamentale importanza (gueli, 2014) ed è stato realizzato usando lo standard white calibration plate (cm-a145) come target per il massimo di luminosità e il device cm-a32 per il 29 cultura e scienza del colore color culture and science | 08 | 2017 | 23 -34 colour quantity contrast in itten’s theory: spectrophotometry for verifying statements issn 2384-9568 table 1 average values and related errors of l* a* b* for all samples analyzed at catania university labs prepared with acrylic, oil and casein. tabella 1 valori medi e relativi errori di l*a*b*per tutti i campioni analizzati a unict stesi con acrilico, con olio e caseina. propagation uncertainty theory, as the square root of the squaring sum of standard deviation and instrumental error. this last contribution was estimated on the basis of cielab coordinates measured on white calibration plate. 4. results and discussion the thirty-six samples, prepared according to the procedure described in paragraph 3.2, were analysed by spectrophotometric measurements performed at catania and napoli universities. each sample was analysed with the same type of instrumentation and following the same experimental parameters illustrated in paragraph 3.2. tables 1 and 2 show the average values with related errors of colour coordinates for the six yellow (y), orange (o), magenta (m), violet (v), cyan (c) and green (g) samples prepared with acrylic, oil and casein vehicles, respectively in the two laboratories. as said in the introduction, this study is born from the hypothesis according to which the itten primary and secondary hues are in a specific relationship, as is illustrated with the values and the related sum in the first column of table 3. in order to compare the data of colour coordinates experimentally measured and those hypothesized in itten statement, the percentage ratio between each reciprocal values of brightness colours, reported by itten and intuited by schopenhauer, and the sum of values of brightness of the six colours are calculated and reported in the second column of table 3. furthermore, for each sample of tables 1 and 2, acrylic acrilico hue cromia liquitex ink lefranc maimeri l*±d a*±d b*±d l*±d a*±d b*±d l*±d a*±d b*±d y giallo 92,8±2,8 -15,1±0,5 87,0±3,4 89,2±2,7 -1,6±0,5 103,0±3,2 90,8±2,7 -7,5±0,9 101,7±3,0 o arancione 41,1±1,4 56,7±1,8 23,6±0,8 52,4±1,6 48,6±1,6 43,3±1,5 56,2±1,7 60,1±1,9 49,8±1,5 m magenta 43,4±1,8 62,6±2,3 4,0±2,2 43,8±1,3 66,0±2,0 -4,3±0,3 51,9±1,6 68,9±2,1 18,2±1,0 v viola 33,1±1,1 18,6±0,6 -24,8±0,8 36,4±1,3 11,0±0,4 -37,7±1,3 41,2±1,2 13,1±0,4 -21,8±0,7 c ciano 54,4±1,6 -17,7±0,6 -32,8±1,1 44,2±1,3 -24,5±0,8 -30,3±1,0 53,5±1,6 -12,6±0,4 -25,4±0,8 g verde 54,9±1,7 -46,3±1,4 9,6±0,4 47,2±1,4 -46,0±1,4 28,2±0,9 53,7±1,6 -33,9±1,6 22,2±0,8 oil olio hue cromia van dick ferrario maimeri l*±d a*±d b*±d l*±d a*±d b*±d y giallo 91,9±2,8 -14,2±0,6 91,6±2,8 88,3±2,7 -4,0±0,6 99,2±3,0 o arancione 56,1±1,8 60,1±2,0 41,1±1,2 46,4±1,5 62,3±1,9 37,4±1,2 m magenta 51,0±1,8 74,9±2,3 6,2±2,6 42,8±1,4 70,7±2,1 0,9± 1,2 v viola 29,2±2,2 18,9±1,6 -36,8±1,1 21,0±0,7 10,7±0,4 -21,8±1,4 c ciano 41,8±2,1 -5,6±2,1 -47,4±1,6 25,7±1,2 -6,1±1,0 -24,5±1,2 g verde 45,6±1,4 -56,1±1,8 6,6±0,5 32,8±1,1 -36,9±1,5 4,7±0,3 minimo di luminosità. sono stati elaborati degli spettri in cui è analizzato l’andamento del fattore di riflettanza spettrale (spectral reflectance factor, srf%) nella regione del visibile e le coordinate di colore nello spazio cielab 1976 (oleari, 2008). l’errore totale, associato ad ogni misura, è stato calcolato, secondo la teoria di propagazione dell’errore, come la radice quadrata della somma in quadratura della deviazione standard e dell’errore strumentale. quest’ultimo contributo è stato stimato sulla base delle coordinate cielab misurate sul white calibration plate. 4. risultati e discussione i trentasei campioni, preparati secondo le modalità descritte nel paragrafo 3.2, sono stati analizzati mediante misure di spettrofotometria a contatto eseguite presso i laboratori dell’università degli studi di catania (unict) e quelli dell’università degli studi di napoli (unina). ogni campione è stato analizzato con lo stesso tipo di strumentazione e utilizzando i medesimi parametri sperimentali descritti nel paragrafo 3.2. nelle tabelle 1 e 2 sono elencati i valori medi delle coordinate cromatiche con i relativi errori ottenuti per i sei campioni di colore giallo, arancione, magenta, viola, ciano e verde, stesi mediante legante acrilico, olio e caseina rispettivamente nei due laboratori coinvolti. come dettagliato nell’introduzione, il presente lavoro nasce dall’ipotesi che le tinte primarie e secondarie di itten stiano in un rapporto preciso descrivibile con le cifre riportate nella prima 30 cultura e scienza del colore color culture and science | 08 | 2017 | 23 -34 di tommaso a. et al. issn 2384-9568 doi: 10.23738/ccsj.i82017.02 hue cromia casein caseina l*±d a*±d b*±d y giallo 70,1±2,3 13,0±0,8 62,2±2,3 o arancione 53,1±1,6 33,7±1,0 38,4±1,2 m magenta 43,5±1,3 44,1±1,3 25,2±0,8 v viola 30,1±1,0 -0,3±0,1 -7,3±0,5 c ciano 33,1±1,1 0,3±0,1 -25,4±0,8 g verde 40,7±2,0 -21,8±0,7 8,5±0,6 acrylic acrilico hue cromia liquitex ink lefranc maimeri l*±d a*±d b*±d l*±d a*±d b*±d l*±d a*±d b*±d y giallo 90,4±2,7 -6,2±0,6 94,0±3,1 86,4±2,6 8,5±0,4 100,8±3,1 88,6±2,7 1,7±0,1 100,5±3,0 o arancione 40,9±1,3 51,4±1,6 21,9±0,7 52,6±1,7 45,3±1,4 43,2±1,5 55,3±1,8 56,1±1,7 47,9±1,7 m magenta 42,3±1,3 55,0±1,7 2,5±0,4 42,8±1,3 57,7±1,8 -6,8±0,3 50,9±1,5 64,5±1,9 14,2±0,6 v viola 33,8±1,0 14,3±0,4 -24,3±0,7 37,5±1,3 2,1±0,1 -33,6±1,3 42,0±1,3 9,6±0,3 -22,0±0,7 c ciano 57,2±1,7 -26,3±1,0 -27,7±0,9 47,0±1,5 -35,8±1,2 -23,6±0,7 55,0±1,7 -18,5±0,6 -21,8±0,7 g verde 55,1±1,7 -45,7±1,4 12,6±0,4 47,3±1,4 -39,3±1,3 28,6±0,9 53,8±1,6 -0,3±0,9 23,4±0,7 table 2 average values and related errors of l* a *b* for all samples analyzed at napoli university labs prepared with acrylic, with oil and casein tabella 2 valori medi e relativi errori di l*a*b*per tutti i campioni analizzati presso unina stesi con acrilici, con olio e caseina oil olio hue cromia van dick ferrario maimeri l*±d a*±d b*±d l*±d a*±d b*±d y giallo 90,2±2,7 -6,3±0,5 92,9±2,8 86,5±2,6 3,9±1,1 99,2±2,9 o arancione 55,8±2,1 53,0±2,0 39,3±1,2 48,2±1,6 54,8±1,8 37,6±1,1 m magenta 50,1±1,6 66,2±2,0 2,8±0,9 43,2±1,5 61,9±1,9 -2,1±1,2 v viola 29,5±1,3 13,0±0,6 -33,8±1,8 24,3±1,0 4,5±0,5 -23,5±1,5 c ciano 45,5±1,4 -20,9±0,8 -39,4±1,3 32,5±1,1 -24,6±1,1 -20,7±0,9 g verde 48,5±1,5 -56,7±1,8 11,5±0,3 36,4±1,4 -42,9±2,3 9,1±0,7 hue cromia casein caseina l*±d a*±d b*±d y giallo 68,4±2,1 12,7±0,5 60,6±1,9 o arancione 53,6±1,6 30,5±1,0 37,6±1,2 m magenta 43,9±1,3 40,8±1,2 23,6±0,7 v viola 34,8±1,3 4,7±0,1 -7,4±0,3 c ciano 36,6±1,1 -4,6±0,1 -23,8±0,7 g verde 33,6±1,1 -21,3±0,6 17,1±0,6 the de* value with respect to the device for black used in the scale adjustment was calculated. in the following text, the de* such obtained is called de* 0 . in particular, first of all, the de* 0 was calculated starting from the l*, a*, b* coordinates and then the percentage of each de* 0 with respect to the sum of de* 0 of the six colours. then, the value of de* 0 in thirty-sixths is reported. the obtained data are presented, with the related error, with the theoretical values, in tables 4 and 5 respectively for the laboratories at catania and colonna della tabella 3 la cui somma è 36. al fine di poter confrontare i dati delle coordinate cromatiche specificate sperimentalmente e quelli ipotizzati nell’enunciato di itten, si è calcolato il rapporto percentuale tra ognuno dei valori reciproci di “luminosità” dei colori riportati da itten e intuiti da schopenhauer e la somma dei valori di “luminosità” dei sei colori (seconda colonna della tabella 3). per ciascuno dei campioni delle tabelle 1 e 2, inoltre, è stato calcolato in trentaseiesimi il valore di de* rispetto al nero di calibrazione. considerato che quest’ultimo rappresenta lo zero in termini di luminosità, nel testo seguente 31 cultura e scienza del colore color culture and science | 08 | 2017 | 23 -34 colour quantity contrast in itten’s theory: spectrophotometry for verifying statements issn 2384-9568 hue cromia absolute reciprocal value of itten brightness (in thirty-sixths) valori reciproci assoluti di luminosità itten (in trentaseiesimi) relative reciprocal value of brightness (in %) valori reciproci relativi di luminosità (in %) y giallo 9 25 o arancione 8 22 m magenta 6 17 v viola 3 8 c ciano 4 11 g verde 6 17 total totale 36 100 napoli universities. the data illustrated in tables 4 and 5 were also elaborated as a histogram (figure 2) realized starting from the values, obtained in the two laboratories and then averaged, of the thirty-six samples prepared with the different vehicles. in the same histogram, the theoretical values of itten/schopenhauer were listed. hue cromia theoretical values valori teorici liquitex ink inchiostri liquitex lefranc acrylic lefranc acrilici maimeri acrylic maimeri acrilici van dick oil van dick olio maimeri oil maimeri olio casein paintings stesure pittoriche con caseina y giallo 9 10,0±0,3 10,1±0,3 9,9±0,3 9,4±0,3 11,4±0,3 9,6±0,3 o arancione 8 5,8±0,2 6,2±0,2 7,0±0,2 6,6±0,2 7,4±0,2 7,5±0,2 m magenta 6 5,9±0,2 5,9±0,2 6,4±0,2 6,5±0,2 7,1±0,2 6,8±0,2 v viola 3 3,5±0,1 4,0±0,1 3,5±0,1 3,6±0,1 2,8±0,1 3,1±0,1 cciano 4 5,1±0,2 4,4±0,1 4,4±0,1 4,6±0,1 3,1±0,1 4,2±0,1 g verde 6 5,6±0,2 5,3±0,2 4,9±0,1 5,2±0,2 4,3±0,1 4,8±0,1 table 3 reciprocal values absolute and relative of itten brightness tabella 3 valori reciproci assoluti e relativi di luminosità itten table 4 de* 0 in thirty-sixths and the related errors calculated for all samples analysed at napoli university tabella 4 coefficienti reciproci de* 0 in 36mi con i relativi errori calcolati per tutti i campioni analizzati presso unina hue cromia theoretical values valori teorici liquitex ink inchiostri liquitex lefranc acrylic lefranc acrilici maimeri acrylic maimeri acrilici van dick oil van dick olio maimeri oil maimeri olio casein paintings stesure pittoriche con caseina y giallo 9 10,3±0,3 10,2±0,3 9,9 ±0,3 9,9±0,3 9,9±0,3 9,14±0,3 o arancione 8 5,5±0,2 6,3±0,2 6,8±0,2 6,6±0,2 6,6±0,2 7,4±0,2 m magenta 6 5,5±0,2 5,5±0,2 6,2±0,2 6,4±0,2 6,4±0,2 6,6±0,2 v viola 3 3,5±0,1 3,9±0,1 3,6±0,1 2,5±0,1 2,5±0,1 3,7±0,1 cciano 4 5,4±0,2 4,9±0,1 4,6±0,1 4,9±0,1 4,9±0,1 4,5±0,1 g verde 6 5,8±0,2 5,2±0,2 4,9±0,1 5,8±0,2 5,8±0,2 4,4±0,1 from figure 2, it is possible to highlight that the yellow measured is always greater than expected, while the orange and the green measured are always less than expected. a further elaboration of the results was made in the figure 3. it is evident that the sum of three pairs of complementary colours is not always constant, as supposed by itten and schopenhauer. the sum of the complementary yellow + violet, also, is always greater than the other two hypothesized. table 5 de* 0 in thirty-sixths and the related errors calculated for all samples analysed at catania university tabella 5 coefficienti reciproci de* 0 in 36mi con i relativi errori calcolati per tutti i campioni analizzati presso unict il de* così ottenuto è denominato de* 0 . nello specifico, è stato dapprima calcolato il de* 0 a partire da ogni terna l*,a*,b* e poi la percentuale di ogni de* 0 rispetto alla somma dei de* 0 dei sei colori. il valore di de* 0 così ottenuto è stato poi espresso in trentaseiesimi. i dati ottenuti sono presentati, con il relativo errore, insieme ai valori teorici, nelle tabelle 4 e 5 rispettivamente per i laboratori dell’università degli studi di napoli e di catania. i dati riportati nelle tabelle 4 e 5 sono stati ulteriormente elaborati in una rappresentazione grafica ad istogramma (figura 2) realizzata a partire dai valori, ottenuti nei due laboratori e mediati, dei trentasei campioni preparati con i diversi leganti. nel medesimo istogramma, inoltre, sono riportati anche i valori teorici di itten/schopenhauer. dalla figura 2 si evince che il giallo misurato è sempre maggiore di quello ipotizzato, mentre 32 cultura e scienza del colore color culture and science | 08 | 2017 | 23 -34 di tommaso a. et al. issn 2384-9568 doi: 10.23738/ccsj.i82017.02 5. conclusions on the basis of which said until now, the authorship of the statement, regarding the relationship of quantity of the six primary and secondary colours of subtractive synthesis of itten, in his book “the art of colour”, is not attributable to goethe but to schopenhauer. the research work, based on colour specification measurements on samples ad hoc prepared, in two different laboratories, allow us to obtain two important results. on the one hand, the study confirms as expected in terms of the qualitative trend of values of reciprocal relationships of the six colours. on the other hand, it puts in evidence a quantitative difference, respect to the six colours theorized by itten, in the quantity contrast. because the importance of the results obtained and foreseeable fallout in several fields, the present research work needs to be explored more deeply by increasing the number of colours and supports samples, improving the preparation steps, and optimizing and standardising the figure 2 histogram obtained with averaged de* 0 in thirty-sixths values of catania and napoli universities in comparison with theoretical ones. figura 2 istogramma dei de* 0 in 36mi mediati misurati da unict e unina confrontati con i rapporti teorici di itten/schopenhauer figure 3 comparison between the averaged sum of complementary coefficients de* 0 measured and the relative theorized by itten/ schopenhauer. figura 3 confronto tra le somme dei coefficienti medi misurati de* 0 in 36mi dei complementari e quelle teoriche di itten/schopenhauer. l’arancio e il verde misurati sono sempre inferiori a quelli ipotizzati. un’ulteriore elaborazione dei risultati è stata fatta nella figura 3 in cui è evidenziato come la somma delle tre coppie di complementari non è sempre costante come ipotizzato da itten e schopenhauer. la somma dei complementari giallo + viola, inoltre, è sempre maggiore rispetto alle altre due ipotizzate. 4. conclusioni sulla scia di quanto argomentato in questo articolo, la paternità dell’enunciato, riguardante il rapporto di quantità dei sei colori costituenti i primari e i secondari della sintesi sottrattiva riferita da itten nel suo libro “arte del colore”, non andrebbe attribuita a goethe ma piuttosto a schopenhauer. il lavoro realizzato, basato su misure di specificazione del colore di provini appositamente preparati, in due differenti laboratori di ricerca, ha permesso di ottenere due importanti risultati. da un lato lo studio ha, infatti, confermato quanto ipotizzato in termini 33 cultura e scienza del colore color culture and science | 08 | 2017 | 23 -34 colour quantity contrast in itten’s theory: spectrophotometry for verifying statements issn 2384-9568 colour coating method in order to achieve a quality surface and homogeneity better than the one obtained. funding this research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. conflict of interest the authors disclose any actual or potential conflicts of interest including financial, personal or other relationships with other people or organizations within three years of beginning the submitted work that could inappropriately influence, or be perceived to influence, their work. bibliography arnheim, r. (traduzione di g. dorfles). (2005) ‘arte e percezione visiva’. milano: feltrinelli, pp. 271-275. burrafato, g., troja, s.o., gueli, a.m., stella, g., zuccarello, a.r. (2005) “misure colorimetriche su stesure pittoriche: messa a punto di un protocollo di misura”, colore e colorimetria contributi multidisciplinari, quaderni di ottica e fotonica, 13, pp. 211-218. giannantoni, g. (a cura di). (1973) ‘aristotele opere. della generazione e della corruzione’. dell’anima. piccoli trattati di storia naturale. roma: laterza, p. 206. goethe, j.w. (a cura di r. troncon). (1987) ‘la teoria dei colori. lineamenti di una teoria dei colori’. milano: il saggiatore, p.252. goethe, j.w. (a cura di r. troncon). (1997) ‘la storia dei colori’. milano: luni editrice, p. 481. gueli, a.m., fontana, d., gallo, s., pasquale, s., stella, g., troja, s.o. (2014) “dal colore alla caratterizzazione ottica di pigmenti antichi: la validità del metodo spettrofotometrico e la teoria di itten”, colore e colorimetria, contributi multidisciplinari, vol. xa, pp. 237-245. itten, j. (traduzione di a. monferini e m. bignami). (1997) ‘arte del colore. esperienza soggettiva e conoscenza oggettiva come vie per l’arte’. milano: est, p. 59. matteini, m., moles, a. (2004). ‘la chimica nel restauro. i materiali dell’arte pittorica’, firenze: nardini, p. 73. official site cts (2017), available at: www.ctseurope.com (accessed: 28 november 2017). official site konica minolta (2017), available at: www. konicaminolta.com, (accessed: 28 november 2017). official site originlab (2017), available at: www.originlab. com, (accessed: 28 november 2017). official site zecchi (2017), available at: www.zecchi.it, (accessed: 28 november 2017). oleari, c. (a cura di) (2008). ‘misurare il colore’, milano: hoepli, pp. 139-244. di andamento qualitativo dei valori dei rapporti reciproci dei sei colori, dall’altro ha evidenziato una differenza quantitativa, rispetto alla sestina definita da itten, nel contrasto di quantità. data l’importanza dei risultati a cui si è giunti e delle prevedibili ricadute in molti ambiti, il presente lavoro richiede di essere approfondito mediante un aumento del numero di campioni di colori e di supporti, migliorando la loro preparazione, ottimizzando e standardizzando il metodo di stesura dei colori al fine di ottenere una maggiore omogeneità superficiale che la manualità della tecnica utilizzata non ha assicurato. 34 cultura e scienza del colore color culture and science | 08 | 2017 | 23 -34 di tommaso a. et al. issn 2384-9568 doi: 10.23738/ccsj.i82017.02 schopenhauer, a. (1830) ‘scriptores ophthalmologici minores. theoriam colorum physiologicam’. lipsiae: hustus radius ed., pp. 22-23. schopenhauer, a. (a cura di m. montinari). (2002) ‘la vista e i colori e carteggio con goethe’. milano: abscondita, pp. 50-53. cultura e scienza del colore color culture and science cultura e scienza del colore color culture and science | special issue on food color | 05 | 2016 7 issn 2384-9568 a comparison of color schemes and images in the package design of sweets in the us and japan 1kyoko hidaka 1faculty of art and design, tama art university abstract this study compares the color schemes and design of packages of sweets in the us and japan from the viewpoint of the cultural history of color. to visualize this comparison, color charts representing typical japanese and american sweets packages are presented. the central aim of the comparison is to clarify cultural differences in color that characterize appetizing sweets, between the us and japan. the research method was as follows: i purchased a total of 120 items, 20 items each of hard candy, chocolate, and chewing gum sold nationally, both in the us and japan in 2013-14. using colormunki design of x-rite, i measured the color scheme of these packages and listed the data in the form of color charts. these data are significant in revealing the fundamental cultural differences in the package design in these nations, a valuable insight for the field of international marketing and graphic/package design. generally, there is a strong tendency for japanese sweets packages to use a warm and light color scheme, whereas american ones apply a vivid multicolor scheme. japanese sweets manufacturers produce various novelty items that promote seasonal and regional marketing, whereas american mass-produced sweets and its coloring are generally aimed at children and their dreams. therefore, the color scheme of and the images on packages of us sweets resemble american comics. keywords color scheme, sweets, packaging, color culture citation: hidaka k. (2016) ‘a comparison of color schemes and images in the package design of sweets in the us and japan’, cultura e scienza del colore color culture and science journal, special issue on food and colour, 05, pp. 07-14, doi: 10.23738/ccsj.i52016.01 received 09 june 2015; revised 14 january 2016; accepted 08 february 2016 cultura e scienza del colore color culture and science | special issue on food color | 05 | 2016 | 0714 8 hidaka k. issn 2384-9568 doi: 10.23738/ccsj.i52016.01 1. introduction this paper compares the color schemes of the package design of sweets in the us and japan from the the cultural studies of color perception and representationa. to visualize this comparison, color charts representing typical japanese and american sweets packages are presented. the main objective of this paper is to clarify the cultural differences in color that characterize appetizing sweets between the us and japan. hues in the color scheme of these package designs are primarily examined. sugita reported that colors that infants see everyday largely influence the human color perceptionb. considering sugita’s biological experimental result [1], i hypothesized that the color scheme of the packaging of sweets can be a root cause of forming color culture since human beings habitually see packages of sweets from childhood. the result of this comparison can expose the cultural distinction in the color perspective and will be valuable in international marketing when exporting japanese sweets. as precedence research, birren published a series of books on color and consumer psychology [2]. kawasome presented a paper examining the relation between food color and human appetite. iyenger, in her book, “art of choosing”, wrote on the issue of how people choose color [3]. 2. method the research method was as follows. i purchased 120 items: 20 items each of hard candy, chocolate, and chewing gum sold nationally, both in the us and japan in 2013-14. the names of stores were wegmans, acme, and hudson news in new york and new jersey; and 100 lawson, aeon, and okashi-no-machioka in tokyo and kanagawa. both in the us and japan, retail stores displayed an average of 18-30 competing products on the same shelves. (figure 1 and 2) using color munki design of x-rite, i measured the color scheme of these packages and listed the data in the form of color charts. from 20 items i selected 3 representative colorsc each: background, main subject motif, product name logotype. figures 3-8 represent the hues of hard candy, chocolate, and chewing gums, which are frequently used. for reference, i compare the typical colors of the sweets packages in the us and japan in munsell notations and rgb variables (figure 9 and tables 1-3). moreover, as an example of the cultural image influencing color, i mention american comics (figure 10). 3. color schemes 3.1 hard candy figure 3 shows that japanese hard candy packages tend to use warm hues, such as red to yellow and light gray; however, they use less green to purple. the use of warm hues and grayish colors gives bright and soft impression overall. furthermore, the japanese data show middle ranges of value and chroma. figure 4 shows the similarity with the japanese data, which also use warm hues. however, there are two differences: first, there is no use of gray, and second, there is frequent use of green. the tendency of not using gray in the us hard candy packages makes it look very colorful and vivid. the us hard candy uses low value (brightness) and high chroma (vividness). 3.2 chocolate figure 5 shows that the colors frequently used in japanese chocolate packages are red, brown (orange and red-purple low in value and chroma), black, and light gray. moreover, they use gold frequently for product logos. in the data, gold appears as yellow and silver appears as gray since rgb colorimetric device does not consider metallic surface. red, brown, black, and gold are four hues that seem to be typical colors for japanese chocolate. in japan, black reminds bitterness and red reminds sweetness. additionally, brown is in between red and black; to make brown hue, people mix these two colors. typical products such as glico’s pocky and lotte’s ghana milk chocolate also use red packages. the bitterer taste and more cacao ingredients the products have, the darker are the hues of the package from brown to black. in contrast, figure 6 displays the frequent color scheme in the us. they use brown, dark gray, yellow-green, and blue. the hershey chocolate currently uses brown in red-purple hue and silver gray. american traditional chocolate snacks, such as milky way and reese, use orange and green, which are not found in the japanese color scheme. 3.2 chewing gums both japanese and us chewing gums frequently use yellow-green to blue-purple and silver (gray) for their packages. these hues represent cool, refreshing sensation of menthol flavor. on the contrary, they scarcely apply orange and brown for their overall background. figure 7 shows that the most frequent hue in japan is silver (gray). japanese chewing gums use metallic colors and do not apply many hues to give an impression of a cool, sharp feeling. black is also often used to express a sharp stimulus. moreover, japanese have an image of healthiness in green color. a unique japanese chewing gum flavor is a this paper is based on the presentation in aic 2015 tokyo: hidaka, k. “a comparison of color schemes and images in the package design of sweets in the us and japan”, poster presentation with the proceedings, aic 2015 tokyo, 2015, p. 426-431. however, in this paper i have redone the color analysis, revised the text and added some figures based on the reviewers’ comments. b sugita experimented color perception of four monkeys by exposing them under various colored light for extensive period of time, and then he proved lighting and experience during infancy considerably change their color perception. c there are also some cases that only 2 colors can be seen in the design. cultura e scienza del colore color culture and science | special issue on food color | 05 | 2016 | 07 14 9a comparison of color schemes and images in the package design of sweets in the us and japan issn 2384-9568 japanese plum, and its red packaging reminds one of ripe plum. american chewing gums use more blue-green than those of japanese. in terms of value, japanese chewing gums use high to medium range of colors, whereas the american package applies low range of colors. furthermore, figure 8 shows that the use of orange in the us is more frequent than in japan. 4. blue colored sweets and package quoting the article from birren, kawasome reported that blue food reduces appetite [4]. it seems that previous research papers have spread such stereotype to the public, especially package designers and food manufacturers. therefore, food packages in japan frequently use warm colors, such as red, which is confirmed in this study. however, in the us, even though “blue” and “fluorescent color” in food rarely exists naturally, this survey found that these colors are widely used in both the packaging and food. 5. results and discussion 5.1 the typical packaging colors of the us and japan this section compares the typical colors from the result of this survey and examines the cultural distinction. here the term “typical” means that these list of colors are happening in the usual way since these are selected as the most frequent colors each nation use. figure 9 illustrates a list figure 1 japanese sweets (left) figure 2 us sweets (right) of typical colors used in packages, sequenced from the first to fifth place. the left column is of the japanese hard candy, chocolate, and chewing gum, and the right column is of the us. comparing these three types of sweets, the divergence of hue is remarkable, particularly in chocolate. in japanese packages, the illustrative images of fruits, green tea, or milk are often used to inform and evoke these flavors. accordingly, the colors of these items reflect the color of the packages. in japan, the use of color in packages of long sellers, basic items versus seasonal, limited, or regional novelties are poles apart. the seasonal, limited ones use more drastic color schemes, whereas the long sellers do not often change the design and colors. american package design generally applies colors in high chroma and low value. unlike japanese, american sweets tend to use illustrative images of contents rather than ingredients. seasonal and limited novelties are also popular in the us, but it seems that these are rather event based, such as halloween, easter, and christmas with its symbolic colorsd. 5.2 american comics and sweets package the mass-produced snacks and sweets sold in american supermarkets and convenience stores are mostly for children, and its coloring is generally aimed at children and their dreams. professor story of university of minnesota pointed out a tendency to use toys and cartoon characters for food advertisement to make cultura e scienza del colore color culture and science | special issue on food color | 05 | 2016 | 0714 10 hidaka k. issn 2384-9568 doi: 10.23738/ccsj.i52016.01 figure 3 japanese hard candy (above) figure 4 us hard candy cultura e scienza del colore color culture and science | special issue on food color | 05 | 2016 | 07 14 11a comparison of color schemes and images in the package design of sweets in the us and japan issn 2384-9568 figure 5 japanese chocolate (above) figure 6 us chocolate cultura e scienza del colore color culture and science | special issue on food color | 05 | 2016 | 0714 12 hidaka k. issn 2384-9568 doi: 10.23738/ccsj.i52016.01 figure 7 japanese chewing gums (above) figure 8 us chewing gums cultura e scienza del colore color culture and science | special issue on food color | 05 | 2016 | 07 14 13a comparison of color schemes and images in the package design of sweets in the us and japan issn 2384-9568 d red & green for christmas, yellow & pink for easter, and orange & black for halloween. figure 9 typical colors in packages figure 10 “superman: silver age dailies vol. 1: 1959-1961” the library of american comics, 2013, superman tm and © dc comics, inc children recognize brands [5]. in particular, m&m, kellogg’s cereal, and oreo cookies use this marketing strategy [6]. thus, it is predictable that the color scheme of these snacks and sweets packages resemble toys and cartoons. in figure 10, superman’s color, which are blue, green, and red shows similarity to the one used in the us sweets. in japan too, children purchase sweets because of bonus toys and the popular anime cartoon characters that are seen on the package. yet, the colors of japanese toys and cartoons may not be as vivid as those of the us. cultura e scienza del colore color culture and science | special issue on food color | 05 | 2016 | 0714 14 hidaka k. issn 2384-9568 doi: 10.23738/ccsj.i52016.01 japan munsell (hvc) rgb usa munsell (hvc) rgb 1 6.6r 4/11 179: 57: 44 1 7.6r 4/12 195: 67: 45 2 4.9y 6/7 187: 158: 66 2 1.9g 4/6 72: 134: 82 3 3.5yr 5/9 213: 122: 57 3 9.2r 4/10 197: 83: 46 4 n 8.0 207: 205: 199 4 4y 7/9 234: 187: 65 5 1gy 6/7 153: 161: 60 5 1.2b 6/5 88: 161: 176 japan munsell (hvc) rgb usa munsell (hvc) rgb 1 6.2r 4/11 180: 57: 50 1 n7.0 180: 181: 159 2 8.6yr 5/5 173: 130: 72 2 0.2gy 6/7 164: 163: 59 3 6.7r 1/3 72: 35: 29 3 1yr 1/1 49: 38: 32 4 n8.0 207: 199: 195 4 7.6pb 3/8 65: 81: 142 5 n1.0 32: 28: 24 5 7.3yr 4/5 137: 96: 47 japan munsell (hvc) rgb usa munsell (hvc) rgb 1 5.1gy 7/1 176: 181: 168 1 9.2g 4/3 82: 129: 117 2 1.7pb 3/4 66: 96: 124 2 8gy 3/4 69: 98: 50 3 9.2gy 5/8 78: 140: 59 3 1.3p 2/2 56: 54: 74 4 3.3r 3/7 128: 50: 40 4 7.9rp 5/9 188: 93: 136 5 9gy 3/4 61: 92: 49 5 1.2gy 7/1 183: 185: 169 table 1 comparison of the typical colors of hard candy in japan and the us table 2 comparison of the typical colors of chocolate in japan and the us table 3 comparison of the typical colors of chewing gum in japan and the us acknowledgements i would like to express my heartfelt thanks to asahi group foundation for their support. bibliography [1] sugita, y. “experience in early infancy for color perception”, journal of the color science association of japan 34(2) 2010, p.164-167 [2] birren, f. “color psychology and color therapy”, university books, 1961 [3] iyengar, s. “the art of choosing”, grand central publishing, 2010 [4] okuda, h., tasaka, m., yui, a., and kawasome, s., “correlation between the image of food colors and the taste sense: the case of japanese twenties”, journal of cookery science of japan 35(1), 2002, p. 2-9 [5] story, m. and french, s. “food advertising and marketing directed at children and adolescents in the us”, international journal of behavioral nutrition and physical activity 2004, p. 1-3 [6] ibid. 6. conclusions the packages of long seller sweets can become the evidence of perception and representation of color in every country. in japan, warm and light colors are used in the basic long sellers, and color scheme variations are seen in seasonal, regional, and limited items. in the us, marketing to children and color scheme of american comics deeply influence the design and colors of sweets packages. humankind forms the color culture—perception and representation by looking at these items on a daily basis since childhood. 28 color culture and science journal vol. 14 (2) doi: 10.23738/ccsj.140204 integrating knowledge about color within the stem/steam approach: some instructional procedural principles berta martini 1 , rossella d’ugo 1 , monica tombolato 1 [1] 1 department of humanistic studies, university of urbino ‘carlo bo’, italy. berta.martini@uniurb.it, rossella.dugo@uniurb.it, monica.tombolato@uniurb.it. corresponding author: berta martini (berta.martini@uniurb.it) abstract this article aims to help define the stem/steam approach to color education. traditional science education seems to fail in addressing the stubborn misconceptions about color vision detected by empirical research. on the contrary, a knowledge integration approach like stem/steam could provide a well-suited educational perspective for dealing with interdisciplinary issues related to color teaching and learning. nowadays more and more schools welcome this educational paradigm as it seems to meet properly the needs of our modern knowledge society. however, this approach is somewhat ambiguous to the extent that a variety of teaching activities fall under the stem/steam label. our original contribution is to attempt to improve the conceptualization of the "stem/steam approach" by identifying some instructional procedural principles that may be useful in operationally defining what we mean by "integration". methodologically, our research consisted of three phases. in the first phase, we identified some shared features of activities classified as stem/steam that we defined as the “invariants” of the stem/steam approach. in the second phase, the invariants were described in terms of didactic variables drawn from the literature and some stem/steam teaching activities. in the third phase, some procedural principles to guide teachers' work were formulated and discussed with reference to color teaching situations. keywords (stem/steam education, color teaching and learning, didactic variables, epistemic variables, learning variables, procedural principles, didactic transposition of knowledge) received 31/01/2022; revised 18/7/2022; accepted 14/10/2022 mailto:berta.martini@uniurb.it integrating knowledge about color within the stem/steam approach: some instructional procedural principles 29 color culture and science journal vol. 14 (2) doi: 10.23738/ccsj.140204 1. some remarks on stem/steam education interdisciplinary topics such as color vision represent a fascinating but difficult challenge to deal with while planning educational curriculum. in a previous article (martini et al., 2019) we tried to make explicit the ambiguity and polysemy of the concept of color, which can take on different meanings in different contexts, imputing to this semantic complexity the multiple naïve conceptions detected by empirical research (e.g., feher, 1992; martinez-borreguero et al., 2013). traditional scientific teaching about color seems not to be very effective in tackling such pervasive and stubborn misconceptions because students often fail to coherently reconcile their experiences of color perception with scientific explanations based on idealized models (giere, 2004). this is the reason why our working hypothesis is that a knowledge integration approach like stem/steam (science, technology, engineering, arts, mathematics) – at least according to a certain interpretation of the acronym – can be a wellsuited educational perspective for dealing with issues related to color teaching and learning. if it is the case, it depends on how stem/steam activities are designed and performed. we begin by briefly clarifying what we mean by the stem paradigm to understand whether and under what conditions it can provide us with some appropriate recommendations for transforming expert knowledge about color vision into knowledge to be taught (chevallard, 1991; martini, 2018). the roots of the stem movement date back to president dwight d. eisenhower, and the formation of nasa and nsf in 1958 (chesky and wolfmeyer, 2015). in the field of science education, the acronym stem – whose first version was smet (sanders, 2009) – was proposed in 2001 by either judith ramaley (assistant director of education and human resources at nsf at the time) or peter faletra (then director of workforce development for teachers and scientists in the office of science at the department of energy) to refer to a group of disciplines (science, technology, engineering, mathematics) identified as fundamental to meet the challenges of the future. historically, the stem movement developed in parallel with the curriculum reform movement whose characteristic feature was a renewed interest in the content and purposes of education even by experts and academics. this phenomenon affected especially the sciences and resulted in the formulation of curricula that considered scientific and cultural advances and the problems that threatened the national security in the climate of the cold war (bruner, 1960). lately, the acronym steam has been introduced, where the addition of the letter "a" that stands for arts addresses the need to integrate creative thinking and applied arts into real-world situations. some scholars believe that the addition of “a” is unnecessary, and that the application of creativity and the arts is a natural premise of stem education. others (e.g., liao, 2016), however, believe it is important to highlight it, because advocating for the “a” might encourage relevant actionable pathways for transdisciplinary learning, allowing for an integration of all curricular disciplines, in line with the goals of school education (martini, 2019). although the instructional models and ideas put forth under the stem label are having a profound impact on the ongoing educational practices in schools all over the world, some educational researchers (e.g., mccomas and burgin, 2020; chesky and wolfmeyer, 2015) have started pointing out limits and contradictions of this potentially revolutionary approach. according to them, an uncritical and politically driven acceptance of stem is indeed occurring to the detriment of a thorough effort to empirically investigate the merits and drawbacks of this approach which appears to be neither unambiguous nor procedurally defined. while professional meetings and science education conferences are increasingly geared toward stem and new textbooks and websites are popping up to advise teachers on how to implement stem practices, stem curricula lack an awareness of what stem is and what stem programs should include. specially, two main and not particularly clear definitions of stem are at issue (mccomas and burgin, 2020). one definition of stem recognizes some degree of epistemic similarity among any of the four subjects that makes them potentially of interest to the same group of educators, but without any expectation that these subjects must be taught together to qualify for the stem label. in contrast, the second definition strongly recommends knowledge integration rather than a mere juxtaposition of different subject matter contents in order to achieve proper stem/steam goals (national science teaching association, 2020). this interdisciplinary approach is also encouraged in k12 education, although there is no universal consensus on how many of the four subjects should be blended and what level of integration should be pursued. in italy, stem/steam education is addressed through different approaches. currently, the recovery and resilience plan presented by italy envisages school reform interventions that enhance stem in response to the need both to increase students' scientific literacy and to identify approaches for teaching scientific disciplines that are more integrated and supported by digital integrating knowledge about color within the stem/steam approach: some instructional procedural principles 30 color culture and science journal vol. 14 (2) doi: 10.23738/ccsj.140204 technologies. great emphasis is placed on the search for connections between disciplines and between theoretical concepts and concrete reality. this perspective aims to bridge the so-called “skill gap” between the notions learned in school and university and the skills required by the world of work. for example, as reported by orizzonte scuola – a well-known news and information portal that is a useful online reference for school employees – stem must mirror real-life scenarios. because real-world jobs are interdisciplinary, children must be encouraged to learn how subjects fit together and work together. since education is no longer about memorizing random facts, but about learning how to think critically, evaluate information and solve problems, knowledge and skills must be taught in an applied way, that is, in a real problem context. although we acknowledge the potential fruitfulness of stem/steam education, we advocate nonetheless that integrating knowledge in real world contexts does not ensure success in learning. on the contrary, the very focus on experience in real contexts, where complex phenomena occur, requires a high control, both epistemic and didactic, over the learning situations. as mentioned above, idealized scientific models constructed to make color vision intelligible cannot be directly inferred from real world phenomena in which many variables interact simultaneously. on the contrary, these epistemic products are the correlate of disciplinary epistemic practices (sandoval, 2016) [2] students need to become acquainted with to make sense of the scientific discourse (tombolato, 2020). this implies that teachers need to clarify not only the conceptual content (e.g., the additive and subtractive color model) but also how that specific content can be related to students' perceptual experience. otherwise, students will continue to interpret scientific models based on ontological and epistemological assumptions about existing entities and the nature of knowledge that stem from intuition, common sense, or personal experiences. according to our perspective, which is characterized by an epistemic approach to didactic problems (martini, 2011; tombolato, 2020), a fruitful way to improve the conceptualization of the stem/steam approach is to identify some instructional procedural principles (stenhouse, 1977) that can be useful to operationally define different ways and levels of knowledge integration. these content-related procedural principles are meant as pragmatic patterns of behavior that can support teachers while performing didactic transposition of expert knowledge about color into school knowledge, enabling them to create specific didactic situations that allow students to develop interdisciplinary learning outcomes and a more sophisticated idea of how scientific knowledge is constructed and legitimated. 2. towards a clarification of the stem/steam approach through the definition of some invariant features methodologically, our research aimed at identifying such procedural principles consisted of three phases. in the first phase, we reviewed the scholarly literature-both theoretical attempts to conceptualize the educational paradigm at stake and the instructional activities labeled by the authors as stem/steam activities-in order to bring out some shared features. the analysis led us to identify four main hallmarks that we defined as the "invariants" of the stem/steam approach. a first characteristic concerns the “integration between disciplines” to overcome their separation and fragmentation. however, constructing interdisciplinary teaching situations implies distinguishing different degrees of integration that concern both the types and the in-depth level of disciplinary knowledge involved. a second characteristic relates to "the integration of theory and practice." often, in education curriculum, the former is treated separately from the latter without considering the relationship that exists in the process of knowledge construction between content and disciplinary epistemic practices. in addition, practice is usually referred exclusively to some kind of manual manipulative skills. in contrast, commenting on laboratory activities conducted in schools, vicentini and cutroni (1996, p. 167) observe that "acting with the hands must be always accompanied by acting with the mind, while acting with the mind can be accompanied by acting with the hands". from an educational perspective, for this invariant to be complied with, it is therefore necessary for disciplinary content to emerge as a result of expert practices in specific contexts. a third characteristic concerns the "integration of disciplinary knowledge into real world contexts". however, referring to real world contexts is not in itself sufficient to ensure successful students learning. the possibility for students to grasp the problem and properly act within the context depends on their prior knowledge and on their awareness of how scientific theorization refer to reality. from an educational perspective, this means controlling the repeated processes of decontextualization and recontextualization of knowledge (chevallard, 1991; martini, 2018). finally, a fourth characteristic concerns the "integration of technologies into teaching". however, making integrating knowledge about color within the stem/steam approach: some instructional procedural principles 31 color culture and science journal vol. 14 (2) doi: 10.23738/ccsj.140204 available and using technologies does not imply better learning, if one is not aware of how technological devices act on both the teaching content and the learner's mind. these features, which pinpoint four different ways of integrating knowledge to be taught and learned, are assumed to be "invariants" of the variety of situations that fall under the stem/steam label. from an educational perspective, the question at hand is how to ensure that these "invariants" are fulfilled. indeed, as they are formulated, these invariants are still too vague and abstract to provide teachers with some useful operational guidelines for designing effective teaching situations. to achieve our goal, we decided to manage the problem of constructing teaching situations consistent with the invariants by identifying for each of them some didactic variables. since teaching action affects the relationships that are built within the teacher-student-knowledge system (the so-called didactic triangle used to conceptualize teaching and learning), both epistemic and learning variables play a key role in this representation. if we agree to represent the problem in this way, then the compliance with the invariants will depend on the variables considered and their relationships. in schematic terms, we can interpret each of these invariants as a function of the relationship between some epistemic and learning variables. if we denote by iid the “integration between disciplines” invariant, by vex a certain epistemic variable x, and by vly a certain learning variable y, then we can write iid = f [r (vex, vly)] similarly, for the other invariants: iitp= f [r (vex, vly)] integration of theory and practice iidr= f [r (vex, vly)] integration of disciplinary knowledge into real world contexts iitt= f [r (vex, vly)] integration of technologies into teaching 3. operationalizing the invariants: the identification of the didactic variables this phase of the research consisted in identifying the didactic variables that allow us to consider both the aspects related to the object of learning and the aspects related to the subject of learning. once the didactic variables were identified, they were combined to give rise to some procedural principles that can provide teachers with some useful tips for designing teaching activities on light and color that are consistent with the four invariants characterizing the stem/steam approach. the didactic variables were drawn from the educational literature and from the analysis of some concrete teaching activities labeled as stem/steam and published in scientific journals or made public on dedicated web portals. here we refer, by way of example, to three experiences aimed at students at different school levels (koyunkaya et al., 2019; dark, 2019; www.stem.org.uk/resources/community/collection/286171 /colour) as they enabled us to evaluate the stem/steam approach to the teaching of content related to light and colors that differ in the degree of depth with which they are covered (simpler or more complex). we also examined the different types of activities and learning environments (e.g., whether they were more or less structured, whether they involved the use of some more or less advanced technological devices, etc.) designed under this approach. the analysis led to the identification of the didactic variables shown in tab. 1. we distinguished between epistemic variables, related to the object of teaching/learning, and learning variables, related to the subject who learns. the former identifies the factors that constrain the teacher's choices about the transposition of scholarly knowledge; the latter refer to the factors on which the learning of each student depends. the latter are therefore crosscutting to all the four invariants. 4. definig some procedural principles for designing color stem/steam activities in the last phase of our research, we formulated some instructional procedural principles based on epistemic and learning variables, which can provide operational guidance for fulfilling the "invariants" that characterize the stem/steam approach, according to our hypothesis. we point out that the invariants and consequently the procedural principles have been isolated from a strictly logical point of view. however, they are closely intertwined, which is why in teaching practice almost every activity exemplifies more than one. in the following, we provide examples of possible procedural principles that can be developed from the didactic variables shown in the table. each of them is discussed with reference to experiences in color education, to clarify the meaning of the four invariants and to support teachers with operational guidelines and practical examples for the design of color learning activities. integrating knowledge about color within the stem/steam approach: some instructional procedural principles 32 color culture and science journal vol. 14 (2) doi: 10.23738/ccsj.140204 stem/steam approach didactic variables invariants epistemic variables learning variables integration between disciplines (interdisciplinarity) disciplines involved (which and how many) level of depth and complexity of the teaching content involved” (basic/advanced) interplay between disciplines (curricular continuity/discontinuity) forms of disciplinary reasoning (analogy, induction, deduction, abduction, by trial and error, probabilistic, by falsification, by models, probabilistic, etc.) level of students' prior knowledge ability level skill level language mastery learning pace preferred learning modes (different sensitivity to didactic mediators) interest and motivation misconceptions ability to use technology integration of theory and practice (knowing and doing) types of knowledge to be integrated type of practical knowledge (expert practice and practice as teaching expedient) degree of formalization of knowledge integration of disciplinary knowledge into real world contexts. historical evolution of the discipline (problems and contexts of genesis and development of knowledge) degree of complexity of the problemsituations integration of technologies into teaching type of technologies (non-digital, analogical, and digital) used as a means to learn certain content technologies used to represent knowledge technologies used to construct knowledge tab. 1. the didactic variables referred to each invariant. 4.1. integration between disciplines 1.1 given equal individual learning factors, a teaching activity is consistent with the stem/steam approach, if it involves multiple disciplines whose different perspectives combined make a specific piece of instructional content more comprehensible than it would be when tackled by any one of them independently. 1.2. given equal individual learning factors, a teaching activity is consistent with the stem/steam approach, if the contribution of the disciplines involved is targeted to the specific teaching content. 1.3. a teaching activity is consistent with the stem/steam approach if the selected topics are covered at the same level of depth within each discipline and if such level of depth is appropriate to students’ prior knowledge. 1.4. a teaching activity is consistent with the stem/steam approach if it has different degrees of complexity that allow it to promote various forms of disciplinary reasoning in learners. a typical integration between disciplines involves science and art. this pairing, though potentially fruitful, requires precise control of the content and its relationships. for example, placing the explanation of the mechanisms of color vision alongside the explanation of pigment mixing without distinguishing the different perspectives from which color is approached is ineffective for both teaching and learning. on the one hand, the content of color integrating knowledge about color within the stem/steam approach: some instructional procedural principles 33 color culture and science journal vol. 14 (2) doi: 10.23738/ccsj.140204 teaching is not organized in a logically coherent way. on the other, learning is prone to generating cognitive conflicts that risk turning into stubborn misconceptions (martini et al., 2019). therefore, procedural principles (1.1. and 1.2) require us to examine whether and how science and art contribute to the understanding of different "descriptions" of color. in other words, we need to make explicit the difference between colored lights and chromatic pigments, as well as what we mean by primary colors, specifying whether we are referring to additive or subtractive synthesis processes, respectively. fig. 1. subtractive color mixing fig. 2. additive color mixing another example involves the integration of science and mathematics. the possibility of integrating these disciplines to promote meaningful learning in students requires controlling the levels of mastery of the knowledge involved (1.3 and 1.4). for example, additive and subtractive synthesis are usually represented through graphical diagrams, such as euler-venn diagrams, which students must be able to understand from a logical standpoint (e.g., koyunkaya et al., 2019, where shadows are represented with three sets and their intersections). if students are not comfortable enough with this type of set representation, they will fail to grasp the rules behind the processes of additive and subtractive color mixing. fig. 3. representing subtractive color mixing with sets (koyunkaya et al. 2019, p. 114). likewise in a teaching situation that proposes a diffraction experiment. to fully understand the quantitative relationship between perceived color and the wavelength of light, students must know the basic concepts of trigonometry and be able to work with them enough to calculate the wavelengths of individual light rays. in this regard, an example of good practice is the open lab on light and color described in dark (2019), where students grasp the relevance of trigonometry as they attempt to answer the challenging question "can light be modeled as a wave?". 4.2. integration of theory and practice 2.1 a teaching activity is consistent with the stem/steam approach if it consistently involves disciplinary content and student-performed practices. 2.2 a teaching activity is consistent with the stem/steam approach if it integrates the theoretical knowledge and practical experience of students in a suitable way to capture their interest and motivation. 2.3 a teaching activity is consistent with the stem/steam approach if it integrates the theoretical knowledge and practical experience of learners in a suitable way to their preferred mode of learning. integrating knowledge about color within the stem/steam approach: some instructional procedural principles 34 color culture and science journal vol. 14 (2) doi: 10.23738/ccsj.140204 2.4. a teaching activity is consistent with the stem/steam approach if the degree of formalization of knowledge is appropriate to students’ prior knowledge and if it considers their different sensitivity to the use of didactic mediators (active, iconic, symbolic mediators). regarding the integration of theory and practice, the procedural principles suggest that we should check for consistency between the theoretical content of instruction and the activities in which the teacher engages students to exemplify or represent that content (2.1, 2.2, 2.3, and 2.4). e.g., it is common for teachers to use newton's disk and colored reflectors to help students understand additive color mixing. we endorse these learning strategies because they are likely to capture students' attention and match their different preferred learning modes through the employment of various didactic mediators. however, if these hands-on activities are not consistent with the theoretical explanation, they can generate misconceptions and false beliefs. for this reason, it is necessary to make students aware of the epistemic goal of the teaching activity by providing them with the relevant knowledge to correctly interpret what they see. for example, in the case mentioned above, you need to make explicit the difference between emitted and reflected light and the different effect you obtain as a result. 4.3. integration of disciplinary knowledge into real world contexts 3.1. a teaching activity is consistent with the stem/steam approach if it involves real-world problem situations that allow students to make sense of disciplinary knowledge. 3.2. a teaching activity is consistent with the stem/steam approach if it involves monitoring the degree of “similarity” between the phenomenon reproduced during the activity and the target phenomenon. integrating disciplinary knowledge into real-world contexts requires strong disciplinary, epistemological and instructional expertise on the part of the teacher. a virtuous example of such integration is accomplished by dark (2019) in her physics and the arts course at spelman university. the connection between arts and science throughout history allows us to become aware of the real problems that scientists and artists had to solve and to grasp the complex relationship between perceived reality and scientific theorizing (3.1 and 3.2). e.g., in secondary and higher education, history can be deployed to help students understand how and to what extent the evolution of scientific understanding of light as a physical phenomenon changed painting techniques and, conversely, how art contributed to the advancement of physics (shlain, 2007). another example of this third type of integration could be the design of a lab in which students must find the best solutions to illuminate a picture with certain characteristics and located in a certain environment, providing theoretical and empirical evidence to justify their choices. fig. 4. children making newton's disk fig. 5 children experiencing additive color mixing with newton's disk 4.4. integration of technologies into teaching 4.1. a teaching activity is consistent with the stem/steam approach if it is supported by technology. 4.2. a teaching activity is consistent with the stem/steam approach if technologies are used by integrating knowledge about color within the stem/steam approach: some instructional procedural principles 35 color culture and science journal vol. 14 (2) doi: 10.23738/ccsj.140204 teachers to present knowledge content in a format that is engaging to students and that fosters their understanding. 4.3. a teaching activity is consistent with the stem/steam approach if technologies are used by students in knowledge-building practices. regarding the use of technologies in color education, some devices allow us to support the teaching practice in a way that ensures consistency with the logical organization of the theoretical content. for example, the representation of additive and subtractive synthesis processes, which usually generate multiple misconceptions due to the inadequacy of the devices employed, can be supported using monochromatic spotlights of adjustable intensity and high reflective screens. fig. 6. experimenting with rgb spotlights as an alternative to the pigment mixture usually proposed in classes, an example of subtractive synthesis can be obtained by illuminating an object from three monochromatic light sources (red, green, blue) simultaneously. the presence of the obstacle allows the formation of shadows that overlapping make available a dynamic representation of the static image usually used to represent the subtractive color mixing. specifically, the areas where the shadows intersect are black, while the areas surrounding the black shadow are colored shadows composed of primary and secondary colors (koyunkaya et al., 2019). in this case, the use of technological devices helps us to highlight the close relationship between the color of the light and the pigment color that many people fail to grasp. indeed, the different types of shadows that appear with the obstruction of light correspond to the absorption of the colors of the light according to the "rules" of pigment mixing. fig. 7. the shadow experiment (koyunkaya et al. 2019, p. 113). 5. conclusion in our contribution, we sought to better define the stem/steam approach to color education by providing teachers with some procedural principles for designing effective instructional activities about color. these principles, conceived as pragmatic patterns of behavior, were formulated by combining epistemic and learning variables that can be traced to the four invariant features of the stem/steam approach previously identified. the research is still ongoing and next goals include identifying more epistemic variables and formulating additional procedural principles to be discussed in relation to color stem/steam activities carried out at different school levels. 6. conflict of interest declaration the authors declare that nothing affected their objectivity or independence and original work. therefore, no conflict of interest exists. 7. funding source declaration this research did not receive any specific grant from founding agencies in the public or not-for profit sectors. integrating knowledge about color within the stem/steam approach: some instructional procedural principles 36 color culture and science journal vol. 14 (2) doi: 10.23738/ccsj.140204 8. short biography of the authors berta martini full professor and head of the dept. of humanistic studies at the university of urbino, where she teaches general didactic and didactic of knowledge. she is co-director of the online scientific journal pedagogia piu’ didattica, and she is a member of the scientific boards of peer review journals and publishing series. her main fields of research are her main areas of research are knowledge transmission processes and curriculum studies. rossella d’ugo researcher in experimental pedagogy at university of urbino – dept. of humanistic studies – where she teaches docimology and experimental pedagogy. her research is mainly oriented to the study of evaluation and self-evaluation tools and methods to ensure the quality of educational contexts as well as of the teaching practices of educators and teachers. monica tombolato phd in epistemology and didactics, she is a research fellow in general didactics at the university of urbino carlo bo, where she teaches didactics of symbolic languages and coordinates the physics laboratories of the degree course in primary education sciences. her current research concerns the contribution of epistemology to the transposition of expert knowledge into knowledge to be taught. notes [1] the paper was written by the authors jointly. specifically, b. martini wrote section 1; r. d’ugo wrote sections 2; m. tombolato wrote sections 3, 4 and 5. [2] by epistemic practices we mean those practices enacted by members of different scientific communities to construct, validate, evaluate, and justify knowledge within a specific field. licensing terms articles published in the “cultura e scienza del colore color culture and science" journal are open access articles, distributed under the terms and conditions of the creative commons attribution license (cc by). you are free to share (copy and redistribute the material in any medium or format) and adapt (remix, transform, and build upon the material for any purpose, even commercially, under the following terms: you must give appropriate credit to authors, provide a link to the license, and indicate if changes were made. you may do so in any reasonable manner, but not in any way that suggests the licensor endorses you or your use, you may not apply legal terms or technological measures that legally restrict others from doing anything the license permits. the authors keep the rights to further publish their contents where they want and can archive pre-print and post-print (submitted version and accepted version) and the published version of the pdf of their article with no embargo period. references bruner, j. 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(eds.) intentional conceptual change. london: lea, pp. 377-406. cultura e scienza del colore color culture and science 29 cultura e scienza del colore color culture and science | 09 | 2018 issn 2384-9568 laurence pauliac lpauliac@hotmail.comrestorations of the monumental polychromy of the gothic cathedrals undertaken by viollet-le-duc abstract the 19th century restoration campaigns of viollet-le-duc constitute the general framework of this study which is limited to the gothic cathedrals notre-dame de paris and treats only one aspect of its restoration: monumental polychromy. by monumental polychromy we refer to the medieval use of colour on the sculpture and on the architectural elements both inside and outside the building. the goal of this paper is to ascertain whether the restorations of the monumental polychromy of the gothic cathedrals undertaken by viollet-le-duc truly uphold the ideal proclaimed by the architect, namely, the restitution of the primitive aspect of the monuments. the first part resumes the concept of restoration according to viollet-le duc. the second part analyses the restoration of the internal polychromy of notre-dame de paris chapels taken by the architect, analysing his choices and the polychromatic system he created. the third part concerns external polychromies. keywords viollet-le-duc, middle ages, gothic, polychromy, colour and architecture, restorations, cathedrals. citation: pauliac l. (2018) ‘restorations of the monumental polychromy of the gothic cathedrals undertaken by viollet-le-duc’, cultura e scienza del colore color culture and science journal, 09, pp. 29-38, doi: 10.23738/ccsj.i92018.03 received 20 october 2017; revised 08 february 2018; accepted 24 april 2018 laurence pauliac, art historian specialist of gothic monumental polychromies and their restorations, is also co-administrator of «couleurs vagabondes». she regularly takes part in the scientific committees for congress and exhibitions about colour (in france and abroad) and publishes articles in connection with her research. 30 cultura e scienza del colore color culture and science | 09 | 2018 | 29 38 pauliac l. issn 2384-9568 doi: 10.23738/ccsj.i92018.03 1. introduction from the 1840’s onwards, viollet-le-duc was one of the principal, if not chief, protagonists in the establishment and execution of the conservation and restoration campaigns of historic architectural monuments in france. the number of building sites he directed in his career is impressive (more than 200) and we owe him the writing of numerous publications, among theoretical essays on the restoration and the famous dictionary of french architecture from 11th to 16th century in 10 volumes (viollet-le-duc, 1854-1868). in 1843 a competition launched to restore the cathedral notre-dame de paris, victim of the torments of time and of the vandalism of the french revolution. it was viollet-le-duc and lassus who wined this competition. through the example of the cathedral of paris, we will try to verify if the restorations of the monumental polychromy of the gothic cathedrals undertaken by viollet-le-duc really respect the ideal of restoration of the architect, namely a return to the primitive aspect of monuments. we will see how viollet-le-duc went against its own convictions. no restoration of the outside polychromy was envisaged, and several of the restorations of internal painted decorations seem to make a reference to personal theories on colour in architecture rather than to gothic chromatic conceptions. 2. restoration according to viollet-le-duc the innovations brought by the architect, real theoretical, technical and historic revolutions, totally transform the world of restoration and their influence is met nowadays too. let’s start our analysis with an extract of his now famous definition of restoration: «le mot et la chose sont modernes. restaurer un édifice, ce n’est pas l’entretenir, le réparer ou le refaire, c’est le rétablir dans un état complet qui peut n’avoir jamais existé à un moment donné » (“the word and the thing are modern. to restore a building, it is not to maintain it, to repair it or to redo it, it is to re-establish it in a complete state which can never have existed at a certain point”) (viollet-le-duc, 18541868). viollet-le-duc’s purpose was to restore entirely a building in a state of perfect historic, structural and stylistic coherence, such as it was, or it should have been once finished. the fact that this “complete state” did exist or not, doesn’t seem capital to him. the most important thing was to return life in the monument by restoring all the physical and material characteristics of a given period. his controversial restoration work was very much criticized over the years but this is not the purpose of this article. we kept three major points of the architect’s theories on restoration directly applicable to the restorations of the monumental polychromy: the return to an ideal state, the respect of the style and the respect of the primitive materials. by studying the attitude of viollet-le-duc as for polychromy and their possible restoration, we will be able to define if he applied to the latter the same principles as in the rest of its restorations. the external factors which have influenced viollet-le-duc will of course be a part of our analysis: financing problems of the restorations, needs and wills of the clergy, contemporary debate on the polychromy, recent reflections and scientific publications on colours and their perception. 3. internal polychromies: notre-dame de paris’s chapels 3.1 the choice of a partial restoration nobody can assert that, in the middle ages, a polychromatic decoration recovered completely the inside of notre-dame, but such decorations were an integral part of this period projects, and considering the importance of the building, the opposite would be very surprising. the objective of our analysis being to verify if the restorations of the monumental polychromy of the cathedral undertaken by viollet-le-duc respect his ideal of a return to the primitive aspect, it is suitable, at first, to study the primitive aspect of the inside of notre-dame, or, more exactly the opinion of the architect on this matter. when the restorations of notre-dame were undertaken, only some rare traces of its original medieval decoration remained. in its monograph on the colour setting of the cathedral chapels, viollet-le-duc recognizes unarguably the medieval will to conceive such polychromatic decorations. however, he supports that: «il est certain que les nefs des cathédrales de paris, de bourges, de reims, d’amiens, de rouen, de chartres, de sens, n’ont jamais reçu de peintures sur les parois de leurs piliers & de leurs voûtes » (“it is certain that the naves of the cathedrals of paris, bourges, reims, amiens, rouen, chartres, sense have never received paintings on the walls of their pillars and their vaults”) (viollet-le-duc and ouradou, 1876). 31 cultura e scienza del colore color culture and science | 09 | 2018 | 29 38 restorations of the monumental polychromy of the gothic cathedrals undertaken by viollet-le-duc issn 2384-9568 and adds: «a notre avis, le temps a manqué pour compléter les conceptions premières. quelques-uns de ces monuments reçurent seulement leur décoration translucide, les vitraux colorés, mais aucun d’eux ne se revêtit intérieurement des couleurs qui devaient contribuer à l’harmonie générale » (“in our opinion, they were short of time to complete the first design. some of these monuments received only their translucent decoration, the coloured stained-glass windows, but none of them put on inside colours which had to contribute to the general harmony”) (violletle-duc and ouradou, 1876). from his point of view if the project of these paintings undoubtedly existed, their execution was not thus able to be led to good port for lack of time (in 1985, the cleaning of the walls of the north and south arms of the transept allowed to discover not insignificant traces of medieval polychromy: the walls of the north arm were totally covered with a uniform coloured bottom stopping in the capitals which receive the fallout of gallery arches whereas blue, red and black colour settings underlined the reliefs of the architecture). further, viollet-le-duc specifies: «la cathédrale de paris […] n’a jamais été peinte à l’intérieur, bien que nous ne mettions pas en doute que l’édifice ait été conçu pour recevoir ce complément décoratif ; mais lorsque, vers le milieu du xiiie siècle, on établit des chapelles entre les contre-forts de sa grande nef, ces chapelles furent, en partie, décorées de peintures ; &, en effet, les murs latéraux de ces chapelles – qui n’étaient que les joues des gros contre-forts – laissaient voir, à l’intérieur, des surfaces froides et blafardes. il fallait nécessairement que ces surfaces fussent occupées par une décoration » (“paris cathedral […] was never painted inside, although we do not question that the building was designed to receive this ornamental complement; but when, by the middle of the 13th century, some chapels were established between the foothills of its big nave, these chapels were, partially, decorated with paintings; and, indeed, the side walls of these chapels which were nothing but the “cheeks” of the big foothills let show, inside, cold and pale surfaces. these surfaces had to be inevitably occupied by a decoration”) (viollet-le-duc, 1854-1868). this event explains the choice made by violletle-duc and lassus right from their first proposals of restoration: a restitution of polychromies in the arms of the transept, the side chapels and the chapels of the chorus only. let us note that this will to mask irregularities and architectural defects by polychromatic decorations corresponds perfectly to one of the missions of the medieval monumental paintings. our purpose is not to examine the accuracy of the restorer’s knowledge of the primitive aspect of the monument but his respect for what he conceived as such according to its own researches, his ideas, but also the historic knowledge of the period. we can thus consider that because viollet-le-duc thought that the inside of the cathedral had never completely received an entire painted decoration, the choice of a partial restoration of this decoration was justified and was corresponding actually to the logic of restoration maintained by the architect. 3.2 the ornamental program viollet-le-duc considered the medieval monumental polychromy as a mean to emphasize the architecture while glorifying it. the good integration of the paintings in the architecture was one of its main objectives. however far from subjecting themself to the architectural effect, the paintings had to take actively part in it. so he specifies: «la peinture décorative grandit ou rapetisse un édifice, le rend clair ou sombre, en altère proportions ou les fait valoir, éloigne ou rapproche, occupe d’une manière agréable ou fatigue, divise ou rassemble, dissimule les défauts ou les exagère. c’est une fée qui prodigue le bien ou le mal, mais qui ne demeure jamais indifférente » (“the ornamental painting increases or makes a building look smaller, makes it either clear or dark, distorts its proportions or asserts them, moves away or closer, occupies the space in a pleasant way or tires, divides or gathers, hides the defects or exaggerates them. it is a fairy who lavishes the good or the evil, but who never remains indifferent”) (viollet-leduc, 1854-1868). these ideas, which resume perfectly the medieval tendencies (to put into relief the existing structures and to create false volumes modulating the space), were however rather audacious for this period. viollet-le-duc contemporaries limited indeed the polychromy to a simple tool of architectural development. the principle set up for the decoration of notredame was based on a more or less identical general plan in all the chapels. their surface was systematically divided into three horizontal zones: 32 cultura e scienza del colore color culture and science | 09 | 2018 | 29 38 pauliac l. issn 2384-9568 doi: 10.23738/ccsj.i92018.03 zone 1: from the base up to approximately two meters off the ground (including the altar). this part of the walls was covered with dense motives in dark tones (figure 1). zone 2: down from the walls up to the vault. the motives decorating the top of the walls are less dense and are executed in clear tones (figure 1). zone 3: the vault and the nervures. a false starry sky covers vaults. the nervures were painted with plain colours or decorated with motives such as chevrons or foliage (figure 2). an ornamented horizontal frieze separates zone 1 and zone 2. vertical friezes also frame the left and right extremities of zone 2 often conferring figure 1 (a-left) cathedral notredame de paris, chapel saint germain, tracing of the paintings made by mr. ouradou. (b-right) explanatory plan of the division in zones of the decoration of the choir chapels. figure 2 cathedral notre-dame de paris, chapel st-georges, an example of vault with false starry sky and painted nervures. a wallpaper look to the set. this last detail is more important than it could seem: thanks to the industrialization, wallpapers knew a success and a phenomenal development in the 19th century. the most important chapels, such as the side chapels of the chorus, received a more developed treatment with narrative scenes illustrating the life of the saints to whom they are dedicated. these scenes are placed over the altar and thus constitute a kind of altarpiece. they are relatively simple compositions, in tint area and without perspective. we have already briefly mentioned that 33 cultura e scienza del colore color culture and science | 09 | 2018 | 29 38 restorations of the monumental polychromy of the gothic cathedrals undertaken by viollet-le-duc issn 2384-9568 when lassus and viollet-le-duc began the restorations of notre-dame its internal original medieval decoration had practically completely disappeared. the most important of the rare remaining vestiges was apparently a mural from the 14th century, which decorated the right wall of the axis chapel. this painting, a madonna with child surrounded with saint denis and with bishop matiffas of buci in prayer (his grave was formerly situated just below), was preserved but directly inserted within the new project of decoration into the same vein as the chapels with narrative scenes. 3.3 the polychromatic system the polychromatic system adopted by violletle-duc for the decor of notre-dame de paris’s chapels is a very good illustration of the architect’s idea regarding monumental painting. viollet-leduc claims to base his entire theories on the study of medieval examples, but their analysis denounces several contemporary influences such as the modern notions of chromatic circle, primary, secondary, complementary colours and the theories of chevreul on the perception of colours. always on the lookout for the last scientific researches and substitute professor of composition and ornament since 1834 in the art school of “rue de l’école-de-médecine”, violletle-duc could not ignore these theories. the catalogue of the books of its library (catalogue des livres composant la bibliothèque de feu m. viollet-le-duc, 1880) shows moreover, that he was himself in possession of a work of chevreul (chevreul, 1867). known for his studies on fat and his works on colours, michel eugène chevreul (17861889) published his essay de la loi du contraste simultané des couleurs (the principles of harmony and contrast of colours) in 1839. named, in 1824, director of the dye works at the gobelins manufactory in paris, he was interested in the theories on the colour within the framework of his functions which included the supervision of the manufacturing of colouring agents being in use to dye the wools of the famous factory. confronted with various problems, he thoughts the colouring agents had, sometimes, nothing to do with chemistry, but more with optics: when a tint did not produce the wished effect, it did not always come from the pigments in use, but from juxtaposed or nearby coloured tones. while developing its works, he discovered and analysed diverse phenomena in relation to the conditions of vision of colours and their simultaneous contrasts, which influenced numerous artistic movements particularly divisionism, impressionism and orphism. in order to understand better the influence of chevreul on viollet-le-duc, let us remind briefly his theory on simultaneous contrasts: two colours juxtaposed on the same surface modify themselves mutually in two manners: as intensity and as nuance. intensity: the clearest lighter seems clearer and the darkest darker. nuance: a colour gives to its neighbour a complementary nuance in the tone. therefore, an orange circle placed on a white bottom makes this one appear blue in its circumference whereas a white circle on a blue bottom seems, on the contrary, orangecoloured. in the case of an orange circle on blue bottom, both colours act mutually to deepen their tints and it is the same for two juxtaposed complementary colours (figure 3). on the contrary, two objects whose colours are close on the chromatic circle tend to throw complementary shadows one on other: yellow takes a purple nuance when placed near green. while opposite complementary get clearer and are mutually excited, non-complementary colours thus tend to damage themselves by mutually “getting dirty”. the harmonious balance according to viollet-le-duc the system established by viollet-le-duc is based on the harmonious balance of the values between muted colour and pure colour (to mute a hue means reducing its purity by adding to it a certain amount of its complementary colour or a grey created from the mixture of the three primary colours). he follows a law on the hierarchy of colours intensity deducted from the analysis of several medieval paintings. this law takes as a base the yellow colour whose value corresponds to 1. the two other primary, red and blue, correspond respectively to 2 and 3, and the secondary colours, orange, green and purple, 3, 4 and 5. according to these observations, in a yellow, red and blue decoration, the yellow has to occupy twice more surface than the red and three times more than the blue so that the harmonious relations between colours are figure 3 simultaneous contrasts of nuances according to the theories of chevreul. a colour gives to its neighbour a complementary nuance in the tone. so, an orange circle placed on a white bottom makes appear this one blue to its circumference, whereas a white circle on a blue bottom seems, on the contrary, orange-coloured. in the case of an orange circle on blue bottom, both colours act mutually to deepen their tints. 34 cultura e scienza del colore color culture and science | 09 | 2018 | 29 38 pauliac l. issn 2384-9568 doi: 10.23738/ccsj.i92018.03 preserved. an artist who chooses to use these three colours will thus obtain logically red and blue motives on yellow bottom (with the red dominating in quantity on the blue). whatever are the chosen tones, some muted hues, relatively neutral, always have to cover the biggest surfaces whereas the pure colour are limited to small parts thus accentuated. the coloured light emanating from the stained glasses, which enlightens the chapels is also at the origin of this harmonious rule which attaches a major importance to shades. according to the calculations of the architect, the coloured lights from stained glasses tend to break down the pure colours and to weigh them down. to fight this tendency, it is necessary to privilege modulated tones according to the colour of glasses: “thus, for example, if windows spread a slightly glazing lilac light and what we want to obtain is a tone of blue, it is necessary to turn the blue into a greenish hue” (viollet-le-duc and ouradou, 1876). the influence of chevreul’s writings is indisputable on this point. in addition, the value of colours to be applied must be chosen according to its intensity. if we take the above example of the ornament with red and blue motives on yellow bottom, the red and the blue have to be of different values, like a red brown and a light blue. viollet-le-duc lists three possibilities of harmony of tones used in the middle ages: • a binary harmony red / yellow with black and white (shade and light). • a tertiary harmony red / yellow / blue figure 3 cathedral notre-dame de paris, chapel saint-louis 35 cultura e scienza del colore color culture and science | 09 | 2018 | 29 38 restorations of the monumental polychromy of the gothic cathedrals undertaken by viollet-le-duc issn 2384-9568 with black and white or with only black. in order to balance the set, this harmony involves necessarily the joint use of green, purple and orange. • a harmony obtained by all the colours with black and gold, where gold is then substituted to white, occupies an essential place to complete or even restore the harmony. the necessity of coloured outlines the systematic use of a black line as colours outlines is not only a graphic game reminding stained-glass windows but it also makes a reference to the concepts of simultaneous contrasts. under the influence of the contrasts, we saw that colours tend to merge and mutually “get dirty”. black outlines prevent their direct confrontation and this fusion feeling. according to viollet-le-duc’s observations, brown-red tones and strong coloured oppositions do not require it. variation of colours according to the orientation of the chapels the choice of the range of colours decorating every chapel was dictated by their orientation and the light’s quality entering in each one of them. starting from observing that half of facing south chapels receives a much more lively and warmly coloured light than the half facing north, viollet-le-duc chooses to keep this difference to protect the harmonious balance. consequently, the north chapels were provided with stainedglass windows in cold and pearly tones whereas south chapels’ received windows in warm tones. in order to keep the general harmony, the pallet of the paintings of every chapel matches the colours of stained-glass windows (figure 4). 3.4 technical and material characteristics concerning the restorations materials and realization’s techniques, viollet-le-duc favoured the use of materials similar to the primitive ones, but, if the latter revealed themselves to be of poor quality, he then used more solid modern substitutes. the execution technique of notre-dame paintings is very badly documented. the only apparently existing information is in peintures murales des chapelles de notre-dame de paris (viollet-le-duc and ouradou, 1876), where viollet-le-duc specifies: «le procédé de peinture employé est dû à m. courtin; nous avons pu reconnaître les qualités de ce procédé, qui réunit une solidité au moins égale à celle de la peinture à la cire la transparence & la fraîcheur de tons que donne la détrempe» (“the painting process here in use is due to m. courtin; we were able to recognize the qualities of this process, which combines a solidity at least equal to that of wax painting and a transparency and freshness of tones like the one given by tempera”) (viollet-le-duc and ouradou, 1876). in spite of in-depth researches, we did not find any document concerning this “courtin process” so praised by viollet-le-duc and its exact composition remains a mystery. maybe the techniques and materials used by the medieval painters of notre-dame seemed too fragile to viollet-le-duc and he preferred a modern process of better quality. however, perhaps the “courtin process” indicates a method similar to old recipes. the importance that viollet-leduc attached to the hard and solid character of the process, close to the final aspect of wax paintings, is not indeed fortuitous. a very wide-spread theory in the 19th century wanted that murals recently found in pompeii were realized with wax polish, which would explain their technical qualities (hardness, resistance in time) and artistic (depth, smooth finished close to some polite marble) – further in-depth studies of these paintings proved that they are realized in fresco. 4. outside polychromies all the previously studied points demonstrate a real motivation of viollet-le-duc to restore notre-dame de paris’s internal polychromatic decorations. the outside paintings did not have the same treatment, neither in notre-dame de paris nor in the other construction sites managed for by the architect and his decision was never questioned. viollet-le-duc described many times notredame de paris’s outside polychromy, in particular in the article “painting” of his dictionary (viollet-le-duc, 1854-1868): «ainsi, à notre-dame de paris, les trois portes, avec leurs voussures et leurs tympans, étaient entièrement peintes et dorées, les quatre niches reliant ces portes, et contenant quatre statues colossales, étaient également peintes. au-dessus, la galerie des rois formait une large litre toute colorée et dorée. la peinture, au-dessus de cette litre, ne s’attachait plus qu’aux deux grandes arcades avec fenêtres, sous les tours, et la rose centrale, qui étincelait de dorures». (“thus, in notre-dame, the three doors, with their arches and their tympanums, were completely painted and gilded, four niches connecting these doors, and containing four colossal statues, were also painted. above, the kings’ gallery shaped a wide coloured 36 cultura e scienza del colore color culture and science | 09 | 2018 | 29 38 pauliac l. issn 2384-9568 doi: 10.23738/ccsj.i92018.03 and gilded border. the paint, over this border, did attach to no more than two big arches with windows, under the towers, and the central rose window, which glistened with gilts”). despite the numerous restorations executed on the facade of notre-dame, it was nevertheless never questioned to restore the polychromy nor to colour the replaced statues. this idea is not even suggested in the form of a possible future project in the report of the restoration project (lassus and viollet-le-duc, 1843), and we did not find any trace of such an intention somewhere else. in the middle ages however, no difference was apparently made between internal paintings and outside paintings and nobody would have been able to imagine a religious monument with walls, architectonic decorations and sculptures were left with a stone appearance: it would have been understood as unfinished, unthinkably incomplete. this analysis allows us to underline and notice that, asking about the attitude of the architect toward the polychromies’s restorations of the gothic cathedrals does not come down to estimate the coherence of its method with its theories. the question actually opens up the way to a problem more profoundly anchored in the ideologies of this time: a taste then almost universal for the purity of bare materials. these monochrome limits, nearly achromes, imposed to architecture and sculpture since the reformation were so rooted in that time mentalities that the rediscovery of antique polychromy by quatremère de quincy in 1814 (quatremère, 1815), far from easing the prejudices, actually re-launched the monumental polychromy debate between opponents and defenders. the architect’s differences of behaviour toward interior and exterior colour setting are completely part of this historic context. mural interior paintings, narrative or not, were appreciated in the 19th century. ornament was fashionable and the decorative aspect of interior paintings certainly had a positive influence. none of the detractors of polychromies “of reliefs” (sculptures and architectonic elements) would have thought of criticizing the internal polychromies. unlike in the middle age, in the 19th century, these two practices did not belong to the same artistic categories (this concept is always true nowadays). in this context, it is very interesting to notice the ambiguity of the architect’s attitude facing monumental exterior colour setting. in spite of its numerous positions against the then used principles, viollet-le-duc had to compose with the prejudices of his contemporaries and external factors such as coal pollution, then very present, and the cost of the possible restorations. in the article “painting” of its dictionary (viollet-leduc, 1854-1868), viollet-le-duc admits that “ornamental painting […] played an important role outside of buildings”. the totality of the paragraph dedicated to exterior monumental polychromy is written in a positive tone leaving no doubt about the architect’s favourable feelings for the object of his study. some passages clarify his opinion even more clearly. and so, he notices: «pourquoi nous privons-nous de toutes ces ressources fournies par l’art? pourquoi l’école dite classique prétend-elle que la froideur et la monotonie sont les compagnes inséparables de la beauté, quand les grecs, que l’on nous présente comme les artistes par excellence, ont toujours coloré leurs édifices à l’intérieur comme à l’extérieur, non pas timidement, mais à l’aide de couleurs d’une extrême vivacité » (“ why do we deprive ourselves of all these resources provided by art? why does the so called classic school claims that coolness and monotony are inseparable partners of beauty, when ancient greeks, introduced to us as the ultimate artists, have always coloured their buildings inside as outside, not in a bashful way, but with extremely bright colours “). however, passages from the article sculpture, in the same dictionary (viollet-le-duc, 18541868), suggest that viollet-le-duc had a more finely shaded opinion. rather than to analyse sculptures in a global way, he separates the formal analysis and the analysis of the possible polychromies. the descriptions that he makes of notre-dame portal sculptures are thus very detailed, but strictly colour free. in addition, pictures illustrating the text are precise and meticulous line drawings, but without colour. it is only at the end of the article, after some long descriptions and formal studies of medieval sculptures, that some passages tackle the issue of colour. the architect’s tone is then very careful, as if soaked by all the quarrels on monumental polychromy, which interested the majority of artists, architects and other intellectuals of this time: «les artistes qui ont fait les admirables vitraux des xiie et xiiie siècles avaient une connaissance trop parfaite de l’harmonie des couleurs pour ne pas appliquer cette connaissance à la coloration de la sculpture. et, à vrai dire, cela n’est point aussi facile qu’on le pourrait croire tout d’abord. les tentatives en ce genre qu’on a faites de notre temps, prouvent que la difficulté en 37 cultura e scienza del colore color culture and science | 09 | 2018 | 29 38 restorations of the monumental polychromy of the gothic cathedrals undertaken by viollet-le-duc issn 2384-9568 pareil cas est grande, au contraire, quant on veut conserver à la sculpture sa gravité, son modèle, qu’on prétend obtenir autre chose que des poupées habillées […] il faut reconnaître que la peinture appliquée à la sculpture lui donne une valeur singulière, mais à la condition que cette application soit faite avec intelligence et par des artistes qui ont acquis l’expérience des effets de la couleur sur des objets modelés » (“the artists who made admirable stained-glass windows of the 12th and 13th centuries had a too good knowledge of colour’s harmony for not applying this knowledge to sculpture colouring. and, in truth, it is not as easy as we could believe it at first. attempts which have been made in our time, prove that the difficulty in such a case is big, on the contrary, when we want to preserve in a sculpture its gravity and its model, we claim to obtain something else rather than dressed dolls […] it is necessary to recognize that paint applied to sculpture gives it a singular value, but provided that this application be made with intelligence and by artists specialized on the effects of colour on relief objects”). viollet-le-duc warns against the effect of “dressed dolls” which apparently characterizes the polychromatic sculptures of his time, but he does not go further than this report and does not suggest trying to restore the polychromies “decently”. when talking about interior decoration, the architect criticized some of the works of his contemporaries but proposed and carried out his own conception of things, concerning the exterior polychromies. he does not go farther than written remarks. these comments have much less eloquence and confidence than many of his writings and only prove the ambiguity of his opinion on the issue. however, can we assume that viollet-le-duc’s personal opinion on polychromy is the only explanation in the fact that he did not restore them? we would be tempted to answer positively. many other components could, indeed, be considered: the financial aspect, a possible agreement (or disagreement) of the church or some other authorities able to wreck such a project. but there is a problem: no trace of project. nowhere in the papers of the architect is mentioned a plan, or, at least the will, to restore exterior paintings. if pecuniary or “diplomatic” motivations had delayed or cancelled the architect’s desires, he would have expressed loud and clear his dissatisfaction and would have made every effort to find new solutions… as an historian and archaeologist, viollet-le-duc had to recognize and, in a way, appreciate the existence of gothic monumental polychromy. but as a restorer, and especially as a man of the 19th century, his opinion on sculpture was soaked by his contemporaries colour free, pure and idealized view. 5. conclusion the only choice to restore a single aspect of this immense entity that we name monumental polychromy contradicts viollet-le-duc’s own principle to give back the monument restored to its primitive state. this “no restoration” of exterior polychromies would be enough by itself to move forward a negative answer to the question that we chose to answer at the beginning of this study. renovations of interior paintings only confirm this answer. the peculiarity of their realization (only in the choir chapels) and the flagrant use of modern theories on colour are as many “compromising” elements. notre-dame de paris’s chapels paintings certainly show a very ingenious use of chevreul’s scientific theories. however, these principles do not correspond to medieval realities and their use contradicts the architect’s restoration ideal. regarding exterior polychromies viollet-le-duc finally never grows away from his colleagues’ ideas, which explains the absence of restoration attempts. it is of course impossible for us to judge the architect’s attitude, it is inscribed in a totally different context from ours and, even today, no restorer ventured to restore a whole cathedral exterior polychromies. despite many incoherencies, the architect’s initiative was so innovative that we can only keep positive aspects for the medieval heritage protection and for monumental paintings restoration science advancement. paintings that we hardly start to really study, more than a hundred years after viollet-le-duc. it would be moreover very interesting to examine the correctness, the accuracy and the relevance of any study on sculpture or medieval architecture that does not take into account polychromy. funding this research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sector. conflict of interest the author disclose any actual or potential conflicts of interest including financial, personal or other relationship with other people or organisations within three years of beginning the submitted work that could inappropriately influence, or be perceived to influence, her work. 38 cultura e scienza del colore color culture and science | 09 | 2018 | 29 38 pauliac l. issn 2384-9568 doi: 10.23738/ccsj.i92018.03 bibliography catalogue des livres composant la bibliothèque de feu m. viollet-le-duc, hôtel des commissaires-priseurs, rue drouot. vente du mardi 18 au lundi 31 mai 1880 (1880). paris: a. labitte. projet de restauration de notre-dame de paris par mm. lassus et viollet-le-duc. rapport adressé à m. le ministre de la justice et des cultes, annexé au projet de restauration, remis le 31 janvier 1843. paris: imprimerie de mme de lacombe. baridon, l. (1996) l’imaginaire scientifique de viollet-leduc. paris:l’harmattan. chevreul, e. (1867) ‘no 580 of the catalogue’, des arts qui parlent aux yeux au moyen de solides colorés d’une étendue sensible et en particulier des arts du tapissier des gobelins et du tapissier de la savonnerie. paris: imprimerie impériale. pauliac, l. (2005) viollet-le-duc et la restauration de la polychromie des cathédrales gothiques, chantal hardy director. montréal: université de montréal. quatremère, a-c. so called quatremère de quincy (1815) le jupiter olympien, ou l’art de la sculpture antique considéré sous un nouveau point de vue, ouvrage qui comprend un essai sur le goût de la sculpture polychrome, l’analyse explicative de la toreutique et l’histoire de la statuaire en or et en ivoire, chez les grecs et les romains. paris: de bure frères. viollet-le-duc, e-e. (1854-1868), dictionnaire raisonné de l’architecture française du xie au xvie siècle, 10 volumes. paris: b. bance et a. morel. viollet-le-duc, e-e. and ouradou, m. (1876) peintures murales des chapelles de notre-dame de paris. paris: a. morel. 14 color culture and science journal vol. 14 (2) doi: 10.23738/ccsj.140202 colours of emotion, trust, and exclusivity: a cross-cultural study peter broeder department of communication and cognition, tilburg university, tilburg, the netherlands. peter@broeder.com abstract colours influence the way people feel, think, and behave. the globalising (internet) economy induces traditions and beliefs to be transferred from one society to another. nevertheless, although people may now act more globally, they also still act locally within their cultural groups. this points to the possibility of continuous change in universal and culturally specific colour associations. therefore, this study aims to investigate variations in colour associations across cultures. to get a better grip on the global impact on the cultural dynamics, cultural groups are distinguished through self-identified membership, instead of through country and nationality demographics. specifically, a comparison is made with the colours for trust, emotion, and exclusivity between 1,218 individuals from four cultural (ethnic) groups: dutch; french; greek; and russian. participating in an online survey, they indicated their associations for colour variations of blue, red, yellow, and black. the results confirm general, universal colour associations. some distinctive independent cultural specifics through varying colour brightness may possibly render the association more or less strong for the colour–attitude relationships of red for emotion and blue for trust. pure yellow was a noticeable colour associated with emotion by the russian group. keywords colour, culture, emotion, trust, exclusivity received 09/12/2021; revised 27/04/2022; accepted 25/07/2022 colors of emotion, trust, and exclusivity: a cross-cultural study 15 color culture and science journal vol. 14 (2) doi: 10.23738/ccsj.140202 1. introduction colours are everywhere and influence people’s attitudes and behaviour. the ongoing process of a globalising (internet) economy causes traditions and beliefs to be transferred from one society to another. however, although people are now acting more globally, they also still act locally within their cultural groups. this points to the possibility of (continuous) change in universal and culturally specific colour associations. several overview studies have noted that colour meanings, as well individuals’ preferences, are moderated by their cultural backgrounds (lee and lee, 2021; yi and shamey, 2015). recently, mohr et al. (2018) noted that prior colour studies have provided too heterogenous findings that were dependent on the context (such as the appropriate colour for interior spaces, logos, websites, etc.). they emphasised that empirical evidence-based investigations are needed to unravel the universal and culturally specific association patterns. in a similar vein, witzel (2019) highlighted misconceptions about colour categories that should be considered. subsequently, colour-specific findings would advance, more generally, the exploration of the biological, ecological, and cultural influences of human functioning. remarkably, crosscultural studies on colour have mostly identified groups by nationality or country. these constructs have provided a rather imprecise identification; it has been increasingly found that comparing national cultures or countries does not reflect reality. a better way of categorising cultures is through (ethnic) selfidentification. this information is more indicative of the cultural identity and considers the dynamics in societies (for further references, see broeder, 2022). the present study addresses this gap in prior cross-cultural colour investigations. members of cultures are identified through their ethnic self-identification. hence, this study aims to unravel colour associations across cultures. new empirical data are presented for four cultural groups in europe. this paper is structured as follows. first, the core dimensions of colour are clarified. additionally, colour variations are related to their impacts on people. specifically, some recent findings are discussed regarding the attitudes and purchase intentions of consumers online. to this end, the findings are detailed regarding the colour association for emotion, trust, and exclusivity, differentiated by the dutch, french, greek, and russian cultural groups. 1.1. colour differentiations colours vary on multiple attributes. the basic dimensions are hue, lightness, and chroma (elliot and maier, 2012; fraser and banks, 2004). hue refers to the wavelength of a colour. human eyes absorb light on different wavelengths, after which our brain converts it into the colours we see. hues are the specific colour variations perceived by human beings (such as in a rainbow). the second colour dimension specified is lightness (or brightness). this is basically the white-toblack attribute of a colour, i.e., the presence of grey (tone), white (tint), or black (shade). finally, the chroma attribute refers to colourfulness. this is basically the vividness of a colour. blue and red are the most investigated and compared colours, detailed overviews for which are provided by labrecque et al. (2013), labrecque (2020), and roschk et al. (2017). traditionally, and in general, some colours are perceived as more attractive than others. according to kodžoman et al. (2022), blue is the most attractive colour, followed by red and green. the least preferred colour is yellow. recently, cross-country investigations by jonauskaite et al. (2016) have supported that, in general, the most preferred hue is green-blue (cyan) and the least preferred hue is yellow. prior studies have discovered that colour variations have different physiological, attitudinal, and behavioural influences (elliot and maier, 2014). physiologically, different colours have been investigated for their influence on heart rate, respiratory rate, blood pressure, and skin-conductance response. saturated and bright colours evoke higher arousal; specifically, red elicits higher arousal than blue (wilms and oberfeld, 2018) and green (kuzinas et al., 2016). several extant studies have found attitudinal effects of interior surface colours, such as the wall colour of a classroom (yildirim et al., 2016), the (paper) background colour of a restaurant menu (magnini and kim 2016), or a luxury hotel room (kim et al., 2020). generally, warm colours are more arousing, exciting, and distracting than cool colours. in particular, the warm colour red is linked to excitement, activity, strength, and stimulation. it stimulates human feelings and activates people (al-ayash et al., 2016; chou et al., 2020; gorn et al., 2004). cool colours are more satisfying than warm ones. these colours, especially the colour blue, are generally perceived as comfortable, relaxing, peaceful, and calming. additionally, they have the potential to decrease anxiety levels (clarke and costall, 2008; song et al., 2020). warm colours have a negative association in terms of evoking pleasure. conversely, cool colours make one feel good, joyful, happy, or satisfied (mazaheri et al., 2011). specifically, in a retail context, cool colours increase (online) shopping intentions (roschk et al., 2017; seckler et al., 2015). colors of emotion, trust, and exclusivity: a cross-cultural study 16 color culture and science journal vol. 14 (2) doi: 10.23738/ccsj.140202 in a general sense, high value colours produce greater feelings of relaxation and greater liking for the brand or product. specifically, for pleasure, light shades of red are recommended (gorn et al., 1997). across 55 countries, jonauskaite et al. (2019) explored the influence of the physical environment on colour associations. they found that people living further away from the equator, in less sunny and more rainy countries, were more likely associate the colour yellow with the emotion of joy. for evoking trust, the most prominent colour is blue, especially compared to the distrust associated with red (su et al., 2019). darker shades, particularly black and purple, express exclusivity and sophistication (labrecque and milne, 2012). for behavioural intentions in online shopping contexts, several studies have confirmed that colours contribute to the web store’s ‘motivational power’ (arousal and emotion) and ‘likeability’ (pleasure) (poels and de witte, 2008). colours have a specific impact on shopping behaviour, such as unplanned purchase, time spent on the web site, and overall satisfaction (choi et al., 2020; koo and ju, 2010; mummalaneni, 2005). specifically, lee and lee (2006) found that a lighter red colour toned down the associations of aggression and active feelings, in comparison to a darker shade of red. 1.2. cultural differentiations adams and osgood (1973) provided a good example of a classic study on cultural colour differentiations. they investigated the affective meaning of eight distinct colour concepts (reported by male high school student groups from 20 countries representing 23 cultures). through a semantic differential consisting of opposite adjective pairs, the culturally diverse group rated colours for the following factors: valuation (good/bad); potency (strong/weak); and activity (active/passive). this threedimensional construct was stable across cultures. for the evaluation factor, the colour blue scored the highest (i.e., most cultures preferred this colour). the most potent colours were black and red; the most active colour was red; black was the most consistently agreed upon colour; and blue was ranked as the most familiar one. follow-up cross-cultural studies on colour meanings have revealed that people of different cultures have a wide variety of types of meanings and attitudes. empirical investigations support the existence of universal and culture-specific patterns for colour meanings. the overall favourite colours have been ordered as follows: blue; red or green; and then yellow (aslam, 2006; bakker et al., 2015; cyr et al., 2010; madden et al., 2000). ou et al.’s (2018) quantitative modelling techniques based on empirical data from 12 regions worldwide presented consistent, culture-independent patterns for colour emotions (regarding warm/cool, heavy/light, active/passive). elaborating on this, witzel et al. (2019) noted that the perception of purer (saturated) red, yellow, green, and blue colours exhibited more cross-cultural stability than other colours. from on (online) marketing communication perspective, broeder and scherp (2017) initiated a series of crosscultural investigations on the influence of colour on online purchasing intention in a mock-up web shop. pure yellow was the most evocative colour where persuasion was concerned. in their study, the colour made western consumers score higher on purchase intention than the pure colours red and blue. a similar, more or less evocative impact of a specific colour could not be found for asian consumers. some recent investigations, following on from broeder and scherp (2017), have indicated that colours contribute to the web store’s motivational power and likeability, consequently enhancing the possibility that the intended behaviour (purchase, booking) is actually performed. in this regard, the colour variations compared in these follow-up studies are presented in figure 1. light values dark values blue trust red emotion figure 1. colour variations compared for blue trust (broeder and snijder, 2019) and red emotion (broeder and wildeman, 2020). broeder and snijder (2019) found that both dutch and chinese consumer groups preferred the use of very dark blue [hsl (208, 50, 20)] over very soft light blue [hsl (209, 50, 70)] in online shopping environments for creating trust. similarly, in broeder and wildeman’s (2020) study, red as the most emotion-inducing colour was investigated among dutch and vietnamese groups: very light red [hsl (0, 100, 75)] was found to be more evocative for purchase intention than dark red [hsl (0, 100, 24)]. 2. method 2.1. objective the present study specifically aims to examine: (1) the associations for emotion, trust, and exclusivity for six colours; and (2) the moderation of cultural background. new empirical insights are presented by differentiating colors of emotion, trust, and exclusivity: a cross-cultural study 17 color culture and science journal vol. 14 (2) doi: 10.23738/ccsj.140202 cultural groups through individual (ethnic) selfidentification. 2.2. participants between 2017 and 2019, an online questionnaire was completed by 1,218 participants from four different cultural groups [the netherlands (n = 567), france (n = 158), greece (n = 298), and russia (n = 195)]. they were selected through non-probabilistic convenience sampling and their cultural background was ascertained through self-identification (‘to what ethnic group do you belong?’). this did not necessarily match their birthcountry or their country-of-living. there were 539 (44%) male and 679 (56%) female participants, and the mean age was 30 years (age range, 15–65 years). the education level was predominantly middle/higher education or university. 2.3. questionnaire the respondents filled in an online questionnaire through qualtrics. the questions were asked in english, which was not the native language of the participants. colour associations were assessed with three questions (‘the colour i associate the most with trust/emotion/exclusivity is …’). for each question, they had to select from six coloured squares: pure blue, dark blue, pure yellow, pure red, light red, and black. the rgb (red, green, blue) and hsl (hue, saturation, lightness) codes of the colours are detailed in table 1; the name labels and codes are derived from www.colorhexa.com. some of these colour variations have been investigated in earlier research by broeder and scherp (2017), broeder and snijder (2019), and broeder and wildeman (2020). table 1. characteristics of the colours used in this study. 3. results 3.1. colour and emotion the colour–emotion profiles for the four groups are presented in figure 2. red, specifically pure red, was associated the most with emotion, whereas dark blue and black were associated with it the least. the proportion of emotion association with pure red reported by the dutch (62%) and greek (57%) respondents was higher compared to that of the french (46%) and russian (39%) ones. notably, yellow emerged as the second colour of emotion as reported by 33% of the russian group (much higher than the other groups). separate chi-square tests confirmed that there was a significant relationship between cultural groups and the emotion–colour profile: χ 2 (15) = 134,998, p < 0.001, phi = 0.192. the colour associations for emotion were independent of gender: χ 2 (5) = 8,20; p = 0.145. figure 2. colour associations for emotion. 3.2. colour and trust for all four groups, blue, specifically pure blue, was associated the most with trust. in comparison, pure red and pure yellow were associated with it the least. figure 3 depicts the trust–colour profiles for the culturally different groups in the present study. figure 3. colour associations for trust. for trust, the proportion of associations with pure blue reported by the dutch (42%) and french (41%) respondents was higher compared to the proportion of russian (35%) and greek (34%) ones. dark blue emerged as the second colour for trust in all four groups. 0% 20% 40% 60% 80% 100% dutch french greek russian emotion pure blue dark blue pure yellow pure red light red black 0% 20% 40% 60% 80% 100% dutch french greek russian trust pure blue dark blue pure yellow pure red light red black http://www.colorhexa.com/ colors of emotion, trust, and exclusivity: a cross-cultural study 18 color culture and science journal vol. 14 (2) doi: 10.23738/ccsj.140202 there was a statistically significant relationship between cultural groups and the trust–colour profile: χ 2 (15) = 34,623; p = 0.003; phi = 0.097. a chi-square test for independence indicated a significant relationship between colour associations for trust and gender: χ 2 (5) = 21,645; p = 0.001; phi = 0.133. notably, the proportion of female respondents who associated pure blue with trust (52%) was comparable to the proportion of male respondents (49%). however, a gender difference was evident for the light red associations. a higher proportion of female respondents (69%) associated trust with light red compared to the male respondents (31%). 3.3. colour and exclusivity figure 4 displays the colour–exclusivity profiles per group. black and dark blue were associated more with exclusivity, while pure blue and light red had the opposite association. figure 4. colour associations and exclusivity. the proportion of exclusivity associations with black reported by the french respondents (15%) was remarkably lower compared to the proportion in the other three cultural groups: dutch (33%); russian (33%); and greek (30%). once again, separate chi-square tests were performed. there was a statistically significant relationship between cultural groups and the exclusivity– colour profile: χ 2 (15) = 119,208; p < 0.001; phi = 0.181. no significant relation was found between gender and colour for exclusivity: χ 2 (5) = 3.94; p = 0.558. 4. discussion this study has investigated universal and culturally specific patterns of colour associations, examining their impact on emotion, trust, and exclusivity as pertaining to dutch, french, greek, and russian cultures. gender differentiations could only be pinpointed for the colour light red; women associated relatively more trust with light red compared to men. across these four cultural groups, the following global similarities in colour associations were found:  red was the colour of emotion; specifically, pure red was associated more with emotion compared with a lighter variation of the colour.  blue was the colour related to trust, whereby pure blue was associated more with trust than a darker variation of blue.  the most exclusive colour was black, followed by dark blue. some local culturally specific associations were reflected in that pure red was associated relatively more with emotion by the dutch and greek cultural groups (vs. french and russian). in addition, pure blue was associated more with trust by the dutch and french cultural groups (vs. greek and russian). pure yellow was a noticeable colour associated with emotion by the russian group. with respect to the colour yellow, a prior cross-country investigation by jonauskaite et al. (2016) found that the least preferred hue is yellow. in contrast, a prior cross-cultural investigation by broeder and scherp (2017) found that yellow is the most persuasive colour for online use in e-commerce. recently, griber et al. (2021) provided an intergenerational linguistic analysis of the russian colour-vocabulary, including the russian terms for referring to the colour yellow. they noted that historic changes in the sociocultural (soviet/russian) reality affected the colour-vocabulary and colour-naming patterns. it can be anticipated that the colour yellow has negative emotional association for russians. this assumption needs to be explored further. this study has limitations that give rise to some suggestions for further research. first, the colour patches were presented in an online questionnaire with the participants asked to select one patch from the series of six coloured pictures. factors such as the lighting of the (computer monitor) environment were not considered. this might have created a confounding variable. in this respect, jonauskaite et al. (2020) found that colour– emotion associations differed between elicitations with colour terms or colour patches in their experiments. there existed high similarity patterns between the two elicitation types for a set of colours including red, blue, and yellow, but not for the (exclusive) colours black and purple. the colour term black elicited more negative associations compared with the colour patch black. second, and further elaborating on the previous limitation, the participants in this study reported basic unipolar colour associations, i.e., the valence aspect 0% 20% 40% 60% 80% 100% dutch french greek russian exclusivity pure blue dark blue pure yellow pure red light red black colors of emotion, trust, and exclusivity: a cross-cultural study 19 color culture and science journal vol. 14 (2) doi: 10.23738/ccsj.140202 (positive or negative) of each concept was not considered. further, cross-cultural investigations might explore the bipolarity of colour associations for the three concepts focused on in the present study. for instance, the emotional valence of red is more likely negative (danger, warning) in western cultures and positive (good fortune, prosperity) in chinese cultures. specifically, in contrast to western stock exchange markets, red represents up-markets whereas green represents downmarkets (jiang et al., 2021). in addition, the strength of specific colour associations might be related to other culturally specific values, such as uncertainty avoidance. for instance, based on recent empirical cross-cultural investigations by broeder (2022), it is a reasonable conjecture that the influence of blue on trust will be stronger in higher uncertainty-avoidance cultures (such as greece and france) compared to lower uncertaintyavoidance cultures (such as russia and the netherlands). in a similar vein, based on the degree of culturally specific individualism (hofstede, 2022), it can be assumed that the exclusivity of black and dark blue will be more prominent in collectivistic cultures (such as greece and russia) compared to individualistic cultures (such as the netherlands and france). third, it is important to keep in mind that in this study, the colours were presented isolated from context. specifically, martinez et al. (2021) noted that, in a retail environment, product and store colours cannot be considered standalone variables. for example, they observed that, in a mock-up blue retail environment, chocolate with a red package was considered more attractive and had higher purchase intentions, compared to blue and beige packaged colours. in contrast, in an orange retail environment, orange packaged chocolate was preferred. in a similar vein, bakker et al. (2015) found different colour preferences among the dutch: white was preferred in residential and office environments; however, black was mentioned as the favourite colour for clothing (more by females than males). 5. conclusion in general, the findings of this study suggest colour variations that are specifically associated with emotion (red), trust (blue), and exclusivity (black). in addition, some specific differentiations relate to the brightness dimension affecting the potential of a colour association. in this study pure red (vs. light red) was reported to be associated relatively more with emotion. pure blue (vs. dark blue) was reported to be associated more with trust. these differentiations seem to be culturally independent from the colour–attitude combinations (red–emotion and blue–trust) that were explored in the current study. further cross-cultural investigations of colours-in-context (elliot and maier, 2012) might reveal the underlying determinants from which colour associations and preferences originate (for references, see gedron, 2017; macdonald et al., 2018; witzel, 2019). 6. declaration of funding sources this research was carried out at tilburg university, the netherlands, and did not receive any specific grant from funding agencies in the public, commercial, or non-forprofit sectors. 7. declaration of conflict of interest the author has declared that no competing interests exist. 8. acknowledgements the author would like to thank the anonymous reviewers for their constructive comments throughout the review process. their insightful and detailed suggestions significantly improved the quality of the final version of this article. 9. short author biography peter broeder (www.broeder.com) is affiliated with the department of communication and cognition at tilburg university, the netherlands. he investigates sociopsycholinguistic aspects of intercultural online marketing communications and consumer behaviour. http://orcid.org/0000-0001-6274-2040 licensing terms articles published in the “cultura e scienza del colore color culture and science" journal are open access articles, distributed under the terms and conditions of the creative commons attribution license (cc by). you are free to share (copy and redistribute the material in any medium or format) and adapt (remix, transform, and build upon the material for any purpose, even commercially, under the following terms: you must give appropriate credit to authors, provide a link to the license, and indicate if changes were made. you may do so in any reasonable manner, but not in any way that suggests the licensor endorses you or your use, you may not apply legal terms or technological measures that legally restrict others from doing anything the license permits. the authors keep the rights to further publish their contents where they want and can archive pre-print and post-print (submitted version and accepted version) and the published version of the pdf of their article with no embargo period. http://www.broeder.com/ http://orcid.org/0000-0001-6274-2040 colors of emotion, trust, and exclusivity: a cross-cultural study 20 color culture and science journal vol. 14 (2) doi: 10.23738/ccsj.140202 references adams, f. m. and osgood, c. e. 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(2015) ‘effect of wall colour on the perception of classrooms’. indoor and built environment, 24 (5), pp. 607–616. doi: 10.1177/1420326x14526214. cultura e scienza del colore color culture and science 69 cultura e scienza del colore color culture and science | 07 | 2017 issn 2384-9568 jodi l. sandford jodi.sandford@unipg.it university of perugia color categorial perception and second language acquisition abstract this paper illustrates results of perceptual and linguistic experiments conducted to verify “categorial perception”, naming, and comprehension of color terms in italian as mother tongue and in english as a second language. i employed franklin, clifford, williamson, and davies’ [2005] experimental procedure to see if young italian children, 3to 5-year-olds would confirm their results of categorial perception in 2 to 4-year-olds. i followed their procedure with the objective of being able to compare the results across the different language groups. franklin et al. found that categorial perception emerges “irrespective of naming and was not stronger in those children with more developed color term knowledge”, and maintain that “color term knowledge does not modify categorial perception, at least during the early stages of childhood”. this research, differently than the original research, argues that linguistic categorization amplifies the category effect: those showing a correct linguist boundary and a betweencategory facilitation scored high in focal naming/comprehension, and in the 2-afc naming score. the tested group demonstrated a good progressive general knowledge of color terms and color fluency, and an apparent interference from second language acquisition showing slightly different linguistic color categories (i.e. blue blu, azzurro, celeste). this is in keeping with the perceptual reorganization model, which postulates an innate predisposition for category boundaries in the color space, and that language learning modifies the location and extent of categorial perception, and may reorganize the representation of perceptual color space. keywords color categorial perception, category boundaries, linguistic color perception, second language acquisition citation: sandford j. l., (2017) ‘color categorial perception and second language acquisition’, cultura e scienza del colore color culture and science journal, 07, pp. 69-76, doi: 10.23738/ ccsj.i72017.06 received 03 february 2016; revised 6 june 2017; accepted 10 june 2016 jodi l. sandford is university researcher and adjunct professor in english language and linguistics at the university of perugia. her specific research interests are in cognitive linguistics, color semantics, embodiment, conceptual metaphor theory, and translation. she has published widely on color semantics and manner of speaking verbs in english, concentrating on empirical studies regarding entrenchment, conceptualization, categorization, implicit attitudes, and fictive motion. 70 cultura e scienza del colore color culture and science | 07 | 2017 | 69 76 sandford j.l. issn 2384-9568 doi: 10.23738/ccsj.i72017.06 1. introduction this paper illustrates results of perceptual and linguistic experiments conducted to verify “categoriala perception”, naming, and comprehension of color terms in italian as mother tongue and in english as a second language. i employed franklin, clifford, williamson, and davies’ [1] experimental procedure to see if young italian children, 3to 5-year-olds would confirm their results of categorial perception in 2to 4-year-olds (the age range considered for the onset of color term establishment reliability acquired of the first focal colors by 3 years and brown and grey 6-9 months later [2]). i followed their procedure with the objective of being able to compare the results across the different language groups. franklin et al. found that categorial perception emerges “irrespective of naming and was not stronger in those children with more developed color term knowledge”, and sustain that “color term knowledge does not modify categorial perception, at least during the early stages of childhood” [1]. the further objective was to verify if there is any variation or interference in categorial perception during the acquisition of a second language that has slightly different linguistic color categories (i.e. blue blu, azzurro, celeste). we understand the color spectrum as a continuum and identify colors through distinct categories. basic or focal colors are easily identified and agreed upon, though the boundaries of these categories are difficult to agree on and tend to vary according to context —when blue is no longer blue and becomes green. a category contains those members that are similar. the more a single item is different from another the more likely it be identified as belonging to a separate category. recognizing that two items belong to separate categories is known as “categori(c)al perception” [3], [4]. categorial perception of color is understood to be activated when colors from the same category are discriminated less easily than colors that cross a category boundary. i tested categorial effect in groups of 3, 4, and 5-year-olds through: ‘two-alternative forced-choice tasks’ (henceforth 2-afcs), a naming test (for the stimuli of the three different 2-afc sets), a comprehension and a naming test of the eleven focal colors. the 3 and 4-year-olds did the training and the tasks in italian, and the 5-year-olds did the training and tasks in english as a second language and repeated the naming and comprehension tasks again in italian. the results of this series of tasks should support one of the three theories of the origins of categorial perception: 1) categorial perception is “hardwired” into the visual system —the universal point of view; 2) categories are constructed by language —the relativist stance; or, 3) categorial perception is a matter of “perceptual reorganization”, somewhere in-between linguistic universalism and relativism. the third option “postulates that there is an innate predisposition for category boundaries at certain points in the color space, but that language learning modifies the location and extent of categorical perception, reorganizing the representation of perceptual space” [1]. the cognitive linguistic approach would explain perceptual reorganization as stemming from our embodied projection of the world, which becomes specialized according to the linguistic construal of the single language-culture-context and the cognitive models thereby developed (e.g. [5]). hence, categorial perception may expand or recede if the category boundary is not specifically reconfirmed by the language(s) acquired or learned. this type of refining mechanism has been found in research on language acquisition [6] and in reference to universal grammar, i.e. principles and parameters [7]. the issues taken into consideration are: will color categorial perception be found in young italian children? what is the impact of language learning on the extent of categorial perception? do children who linguistically mark the boundaries show categorial perception, or is categorial perception greater if children linguistically mark the boundaries [1]? does knowledge of a second language alter accuracy in categorial perception? 2. experiment overview to test for categorial perception, the first task involved the 2-afcs, which is the same test used with adults, though adapted for young children. the methodology is explained in the next paragraph. as illustrated in fig. 1., adapted from franklin et al. [1], categorial perception tests stimuli grouped into a set of three: a1, a2, and b. they are equidistant in the color space. two stimuli, a1 and a2 belong to the same linguistic category (e.g. green), and b belongs to a different linguistic category (e.g. blue) adjacent in the color space. categorial perception is evinced when the participant identifies the stimulus pair a2-b more accurately than the stimulus pair a1-a2. researchers have verified categorial perception in same-different judgment, recognition memory, and 2-afcs [1], [8], [9], [10], [11]. both franklin and davies [12] and franklin et al. [1] have shown that young children demonstrate categorial color perception across the greenblue, blue-purple hue boundaries, and across the red-pink lightness and saturation boundaries. this experiment calqued the previous studies using the same color boundary groups. i prepared three sets of stimuli, (1) green: 71 cultura e scienza del colore color culture and science | 07 | 2017 | 69 76 color categorial perception and second language acquisition issn 2384-9568 green, blue-green, blue, (2) blue: blue, purpleblue, purple, and (3) red: red, pink-red, pink. i investigated the size and effect of each category by judging the accuracy of identification in the task between the foil and the target pairs. i used the naming tasks of the stimuli sets to reveal the presence of a linguistic category boundary. i grouped the naming patterns of the test stimuli as belonging to the group of: no linguistic boundary, a correct linguistic boundary, and a reversed linguistic boundary. as franklin et al. [1] state: “if the linguistic categorization creates the category effect (linguistic relativity model), then (a) those children with no linguistic boundary should show no category effect, (b) those children with a correct linguistic boundary should show between-category facilitation, and (c) those children with a reversed linguistic boundary should show within-category facilitation. if linguistic categorization amplifies the category effect (perceptual reorganization model), then (a) those children with no linguistic boundary should show weaker category effect than those children with a boundary, (b) those children with a correct linguist boundary should show between-category facilitation; and (c) those children with a reversed linguistic boundary should show within-category facilitation. if linguistic categorization has no impact on the category effect (universalistic model), then all children would respond categorially to the same extent, irrespective of their pattern of naming” (p.122). the further comprehension and naming tasks were administered to verify the general linguistic knowledge of the 3-5-year-olds (henceforth yos) figure 1 illustration of categorial perception between two categories: a and b. each box represents a stimulus that is spaced equidistantly from the other. the dashed line represents the category boundary of the 11 focal colors and to record the general fluency. i hypothesized that the children’s general knowledge of color terms may be linked to categorial perception if a correlation between language knowledge and categorial perception emerges. i further hypothesized that language may affect the children’s clarity of categorial perception when learning a second language, especially when the two languages mark the boundaries differently. in this case the second language, english, may affect the boundaries of the tested categories, i.e. blue. english categorizes the macro area blue, including the italian subordinate categories of blu and azzurro, and possibly celeste [12]. furthermore, requiring the informants to identify half tones of blue-green, purple-blue, or pink red as a different tone than the focal color could stimulate a linguistic accessing of something other than the terms green, blue, or red. this could give rise to naming frequent italian terms that cross these color category boundaries. 2.1. methodology participants: a total of 56 native italian speakers (28 males and 28 females) between the ages of 3 and 5, agreed to participate in the experiments. the scuola dell’infanzia “lucina” in perugia was very cooperative in allowing anna testi to come to the school and work with the children in their own environment. the groups that were tested only in italian were comprised of: 19 3yos (8 males and 11 females) and 18 4yos (10 males and 8 figure 2 bear figures in medium grey pantone color (left) figure 3 focal stimuli paper sweaters (right) 72 cultura e scienza del colore color culture and science | 07 | 2017 | 69 76 sandford j.l. issn 2384-9568 doi: 10.23738/ccsj.i72017.06 females). the group tested in italian and english consisted of 19 5yos (10 males and 9 females). the 5yos had already participated in over 22 hours of english activities aimed at learning various english expressions (conventional greetings, holiday terminology, colors, family members, farm, forest, and jungle animals, and fruits and vegetables). the native english teacher conducted the matching and memory games using objects and flash cards, through one hour a week activities, working both on comprehension and performance. stimuli and design: for the 2-afcs we made two bears on plasticized medium grey heavy paper, pantone 403c, which had smiling faces drawn in black ink. the colored sweater stimuli were made of the same printed-paper and plasticized to withstand the practice and task usage of 56 children. each paper sweater was the same size and shape. to allow for easy application to the bear, a velcro strip was glued on the bears’ tummy and on the back of the paper sweaters, so when the child had selected and applied the chosen sweater it would stay in place. focal stimuli: different than the original test [1] we used pantone coordinates to make sure that the colors were constant, measurable, and reproducible. the pantone colors corresponded to the original munsell colors as indicated in franklin et al. [1], and were measured for compatibility by a typographer. the colors included: white (bianco), black (426c), red (1797c), green (361c), yellow (107c), blue (p072m), brown (7518c), pink (1767c), purple (ppurple), orange (1585c), and grey (430c). two sweaters per color were made for the 11 focal colors, in keeping with the basic color terms in english [13]. test stimuli: we used the pantone coordinates that corresponded to the colors established in, and confirmed by, adult naming and similarity judgments [10]. the test stimuli were made according to these three sets and were broken down in the following manner according to the pantone code that corresponded to the munsell code. the green set is: green (361c = 7.5g 5/10), blue-green (562c = 5bg 5/10), and blue (p072 = 2.5b 5/10) (with 7.5bg indicated as the boundary). the blue set is: blue (p072 = 10b 3/10), purple-blue (pviolet = 7.5pb 3/10), and purple (ppurple = 5p 3/10) (with 10pb indicated as the boundary). the red set is: red (1797c = 5r6/10), pink-red (1787c = 5r5/12), pink (1767c = 5r4/14). figure 4 shows the approximate hue of the color patches; some variation in color due to the phases of print or online versions should be kept in mind. the first two columns in fig. 4 (green and blue-green, blue and purple-blue, and red and pink-red) comprised the “within category” couples and the middle and last columns (blue-green and blue, bluepurple and purple, pink-red and pink) comprised the “between category” couples. (see also franklin et al [1] original diagram of within and between category differences in appendix). the procedure was conducted in a nonstandardized lighting condition, though the situation was the same for all of the participants. we tested each child individually in the wellknown environment of their school library with natural mid-day sunlight that penetrated on three sides of the room; in relation to the child’s right, front, and left. no artificial light or shadow interfered with the representation of the experimental stimuli. we chose the place that the children were used to, with the precise aim of verifying how they would normally respond to linguistic identification of color in both performance and comprehension. procedure: all children completed the 2-afc task, naming, and comprehension tasks after a training session. the training session consisted in familiarizing them with the task using the focal colors (fig. 3). we showed them how when one bear wore a colored sweater, the other bear should wear the same color sweater, and that figure 4 test stimuli color sets: green, blue, red 73 cultura e scienza del colore color culture and science | 07 | 2017 | 69 76 color categorial perception and second language acquisition issn 2384-9568 they could pick it out of the sweaters on the table and put it on the other bear. we placed the two bears and the two sets of sweaters on the table in front of the child, a color was randomly selected from set a and placed on bear a, the child was asked to pick out the corresponding sweater for bear b from set b. we went through this process three times with different colors, before proceeding with the more complex task. bear b and its set of sweaters was covered with a white piece of paper while the test stimulus –bear a and an a sweater– was uncovered for 5 second exposure. then bear a was covered for another 5 seconds, before uncovering bear b and the b sweater set. after the child had made his/her selection and placed it on bear b, we uncovered bear a to allow the child to evaluate his/her choice. the child was praised with a matching choice and encouraged to modify it, if not. each child carried out this task successfully three times before proceeding to the 2-afc task experiment. each child was tested on only one of the color sets. in the 2-afc task we used only the test stimuli (fig.4), and the procedure was the same as the second part of the training. this randomized task limited the choice between two sweaters: the correct choice (the target) was the exact color of bear a’s sweater, and the incorrect choice (the foil) was either a between or within category color sweater. the categorial relationship –between and within– was poised twice to each child, for a total of four judgments. we then showed the stimuli sweaters to the child and asked what color they would call the sweater. comprehension and naming: after completing the 2-afc tasks, we laid out the focal color sweaters and asked the child to put, for example, the “red” sweater on the bear. each color was tested and the child’s response recorded. after this, the focal stimuli sweaters were put out on the table and the child was asked to name the colors. 3. results three category boundaries: on the whole category effect was manifested. we calculated the number of correct judgments for between category and within category for each participant. accuracy resulted in 86.25% target-foil choices of the between category compared to a 76.34% target-foil choices of the within category. considering each set separately, an unusual result emerged: the green set accuracy was higher for within category 94.74% compared to 86.84% between category accuracy. in keeping with [1] the blue set accuracy was higher for between 78.94% than within 52.63%. and the red set accuracy was higher for between 94.44% than within 69.44%. even though the within category was higher for green, the between category accuracy for green was higher than the blue set between accuracy, and close to the red set between accuracy. our results, sandford (s), were higher for overall accuracy per set than franklin et al. (f) for green 93.42% (s) 60.62% (f) and red 80.55% (s) 56.87% (f), and slightly lower in the blue 72.37% (s) 77.50% (f). the higher percentages of accuracy are most likely due to maturation, since we included the 5yos to test second language acquisition. the average of correct 2-afc answers grew with age: 3-yo mean 3.1, 4-yo mean 3.2, and 5-yo mean 3.6, out of 4 possible. categorial perception emerged according to accuracy for all three sets. naming accuracy and comprehension: the majority of the color names given for the three 2-afc sets were accurate. the accuracy ranged in the green set: green 100%, blue-green 74%, blue (blu) 95%; in the blue set: blue 85% (+5% celeste), purple-blue 49% (+ 5% azzurro), purple 54% (+ 31% fucsia); and in the red set: red 100%, pink-red 67% (+17% fucsia), pink 90%. following are the names given in italian, in order of high to low percentage, with an asterisk marking those considered erroneous. the green set names were: green (verde), blue-green (verde scuro, verde acqua, *blu, *azzurro), and blue (blu, viola). the blue set names were: blue (blu, celeste, *bianco, *arancione), purple-blue (viola, viola scuro, *blu, *azzurro, *celeste, *rosa, *bianco), purple (viola, *rosa, *fucsia, *rosso). the red set names were: red (red), pink-red (rosso, *rosa, *fucsia, *arancione), pink (rosa, *viola, *fucsia). the method used to calculate the linguistic boundaries followed [1], though our results showed no child without a boundary, and some children with three distinct boundaries. a total of the naming task results show a majority, 62.50%, manifested a correct between category linguistic boundary, by assigning two names to the three stimuli (3yos 23.21%; 4yos 17.86%; 5yos 21.43%). another 17.86% gave three different color names for each set of three (3yos 7.14%; 4yos 7.14%; 5yos 3.57%), demonstrating an advanced linguistic awareness that each color tone may have a different label; though 12.5% gave accurate labels (e.g. fucsia for pink or purple; azzurro for blue halftones), the other 5.36% were more approximate (e.g. celeste for blue, blue-purple; arancione for pinkred). 3.57% gave wrong labels, but recognized a difference. considering the 3-label children with the other between linguistic boundaries, 80.36% total demonstrated linguistic boundaries. the other 19.64% showed a reversed boundary. no children showed no linguistic boundary in italian. color term comprehension and naming: all of the children scored mean 92.05% of comprehension of the focal color terms, and 91.07% named the focal color sweaters correctly. the mean accuracy score on comprehension and naming 74 cultura e scienza del colore color culture and science | 07 | 2017 | 69 76 sandford j.l. issn 2384-9568 doi: 10.23738/ccsj.i72017.06 categorization amplified the category effect along with maturation of the individual. the three different age groups emerged each with gradually higher average scores on the 2-afc task (17 errors for 3yos, 15 for 4yos, and 8 for 5yos; see §3). they also had progressively higher scores on naming 2-afc stimuli accuracy: 3yos 2.37, 4yos 2.67, 5yos 2.68. the subordinate color terms that the children were stimulated to access in the 2-afc naming task included azzurro, celeste, and fucsia. in a previous study by sandford [14] azzurro [blue/light blue], rosa [pink/ rose], celeste [blue/sky blue], and fucsia [fuchsia/ magenta] ranked close to and above some of the 11 focal color terms in cognitive salience. each subordinate term in italian is translatable into more than one term in english and could result in the naming a half-tone: azzurro in blue, green, or purple; celeste in blue and possibly green; and fucsia in purple or pink. the focal color naming/ comprehension tasks showed a high degree of accuracy, with a slightly lower percentage for the 5yos. this most likely was due to the english interference in the training and task experience and the general process of second language acquisition. the 2-afc halftone purple-blue and pink-red stimuli, and full tone purple naming accuracy were lowest. difficulty in naming accuracy for the “blues” seems relevant to the restriction of linguistic category in english. or as suggested by a referee of this paper, the discrimination capacity of minimal differences in color hue is highest in the colors around green and yellow, but decreases dramatically toward blue and red; which could be reflected in these results. 5. conclusions this research, differently than [1], argues that linguistic categorization amplifies the category effect: those showing a correct linguist boundary and a between-category facilitation scored mean 20.30 in focal naming/comprehension, and mean 3.48 on the 2-afc naming score. those few showing a reversed linguistic boundary and within-category facilitation scored mean 19.54 in focal naming/comprehension, and mean 3.4 on the 2-afc. no children in this study showed no linguistic boundary in italian, yet 23.32% of the 5yos did in english. the group demonstrates a good progressive general knowledge of color terms and color fluency, which is in keeping with the perceptual reorganization model. the model as described in [1] postulates an innate predisposition for category boundaries in the color space, and that language learning modifies the location and extent of categorial perception, and may reorganize the representation of perceptual color space. athanasopoulos et al. [15] also confirmed respectively is: 3yos 84.21% and 78.94%; 4yos 97.50% and 98.00%; 5yos 93.79% and 96.16%. the 4yos did best in comprehension and naming. the 3yos did better on comprehension than naming, and both the 4yos and 5yos did slightly better on naming than comprehension, which [1] affirms as expected. we calculated a general term fluency index, explained in [1], by averaging the mean number of colors named and the mean number of colors identified: a result of 20.14 out of 22 focal colors. a categorial effect index was calculated by subtracting the within-category score from the between-category score (on the 2-afc task) for each child. a score higher than 0 indicates a categorial effect; that is, between-category accuracy is greater than within-category accuracy. a score of 0 indicates no categorial effect. a score lower than 0 indicates a reversed categorial effect, within-category being higher that between-category accuracy. the categorial effect was 0.71 indicating a general result of between-category boundary. 3.1. second language results there are several things to consider in the 5yo group: their accuracy scores were not as high as the 4yos, which i would argue has to do with interference from second language acquisition. often there is a period during second language acquisition where there is a set back in linguistic performance, before a general advancement [6]. naming and comprehension: the actual performance and competence in english was tested three times. naming the 2-afc stimuli: the mean accuracy was 1.47 out of 3 in english (2.68 in italian). the linguistic boundary for the 5yos emerged as between category for 47.37%, no linguistic category for 26.32%, and reversed for 26.32% in english (between category for 68.42% and reversed for 31.58% in italian). the between category children in both languages were the same, though fewer in english due to lack of color term production. naming of the 11 focal colors averaged 6.21 in english, and 10.57 in italian. comprehension of the 11 focal colors averaged 8.1 in english, and 10.32 in italian. the average of naming and comprehension was 65.09% in english, and 94.95% in italian. 4 discussion the group responded accurately to all three boundaries with an average of 86.25%. though the category effect was evident for the blue (0.68) and red boundaries (0.55), the green boundary showed a slight within category effect (-0.15). the distant boundary ratio a1-b was the most accurate of the between category tasks. considering the effect of naming on the size of the category effect, it seems that the linguistic 75 cultura e scienza del colore color culture and science | 07 | 2017 | 69 76 color categorial perception and second language acquisition issn 2384-9568 this model with electrophysiological evidence. the increased error in color naming in italian by the 5yos, who were in the process of acquiring a second language, would seem to further confirm this model and reflect language interference. nonetheless, the high degree of accuracy makes it difficult to tease out the variation of perceptual category effect, and at the same time there was greater general accuracy in categorial perception than in linguistic ability to mark the boundary. this, and the higher mean number of 3yos in establishing a between boundary in naming, allows us to evince that categorial perception is independent of color naming. [1] states that “infant color categorial perception has been found in british and american infants, but no such tests have been made on infants from other language groups”, this research evinces that young italian children also demonstrate categorial perception. aknowledgments i would like to thank anna testi for carrying out the experiments conducted for this study. some of this data was used for her ma thesis: what color is this? young children’s linguistic color categorization a case study, università degli studi di perugia, 2012-2013. funding this research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. conflict of interest to my knowledge no potential conflicts of interest exist, i have quoted franklin, clifford, williamson, and davies’ [2005], and show the original category boundary indications of the color couples tested. notes a since the topic of discussion is “categorization”, i opt to use “categorial” i.e. of or relating to a category, rather than “categorical” i.e. definite, uncompromising, unconditional, to thus disambiguate between the two lexemes, even though in this literature “categorical” tends to be used. bibliography [1] franklin, a., a. clifford, e. williamson & i.r. davies, color term knowledge does not affect categorical perception of color in toddlers. journal of experimental child psychology 90, 114–141, 2005. [2] pitchford, n.j. & k.t. mullen, is the acquisition of basiccolor terms in young children constrained? prception, 31, 1349-1379, 2002. [3] hanard, s. psychophysical and cognitive aspects of categorical perception: a critical overview. in s. harnard (ed.), categorical perception: the groundwork of cognition. new york: cambridge university press, 287-301, 1987. [4] taylor, j.r., linguistic categorization, oxford: oxford university press, 2003. [5] lakoff, g. women, fire and dangerous things, what categories reveal about the mind. chicago: the university of chicago press, 1987. [6] saville-troike, m., introducing second language acquisition. cambridge: cambridge university press, 2012. [7] chomsky, n., lectures on government and binding: the pisa lecture, mouton de gruyter. berlin. 1981/1993. [8] bornstein, m.h. & n. korda, discrimination and matching within and between hues measured by reaction times: some implications for categorical perception and levels of information processing. psychological research, 46, 1-22, 1984. [9] pilling, m., a. wigget, e. özgen & i.r. davies, is color “categorical perception” really perceptual? memory & cognition, 31, 538-551, 2003. [10] roberson, d., & j. davidoff, the categorial perception of colors and facial expressions: the effect of verbal interference. memory & cognition, 28, 977-986, 2000. [11] uchikawa, k. & h. shinoda, influence of basic color categories on color memory discrimination. color research and application, 21, 430-439, 1996. [12] franklin, a. & i.r. davies, new evidence for infant color categories. british journal of developmental psychology, 22, 349-378, 2004. [13] kay, p., b. berlin, l. maffi, w. merrifield & r. cook, the world color study. csli center for the study of language and information, standford, california, 2009. [14] sandford, jodi l. “a cognitive linguistic usage perspective: what is italian blu, azzurro, celeste do english speakers agree on blue semantics?”, selected papers cultura e scienza del colore color culture and science, 4, 2230, 2015. [15] athanasopoulos, p., a. wiggett, b. dering, j. r. kuipers & g. thierry, the whorfian mind: electrophysiological evidence that language shapes perception. communicative & integrative biology, 2, 1-3, 2009 76 cultura e scienza del colore color culture and science | 07 | 2017 | 69 76 sandford j.l. issn 2384-9568 doi: 10.23738/ccsj.i72017.06 appendix taken from franklin et al. [1] page 124, their figure 2 – munsell codes, categorial status, and munsell distances of the stimuli of the experimental pairs used. the categorial relationships (within or between) of the experimental pairs are shown for blue-purple (a), blue-green, and hue boundaries and a pinkred lightness saturation boundary (c). in panel a, chroma = 3 and value = 10. in panel b, chroma = 5 and value = 10. in panel c, hue =5r. this page has been intentionally left white 47 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110106 painted or not painted? discovering color traces of ancient stones susanna bracci 1 , donata magrini 1 , giovanni bartolozzi 2 1 icvbc-cnr, florence, italy, bracci@icvbc.cnr.it, d.magrini@icvbc.cnr.it 2 ifac-cnr, florence, italy, g.bartolozzi@ifac.cnr.it corresponding author: susanna bracci (bracci@icvbc.cnr.it) abstract although many ancient civilizations are known to have made use of polychromy on sculptures and in general on stone artifacts, today much of these colours went lost. for this reason, in the minds of a very large majority, the original stones have remained un-coloured until today. the small amount of these traces lead to a new approach for their characterization in order to limit sampling and hopefully, avoiding it. the non-invasive approach permits the examination of a very large number of artworks with a virtually limitless number of analytical acquisitions allowing to perform measurements in situ. already during the measurement process, this approach leads to a fundamental exchange of views among scientists, archaeologist, conservators and art hystorians. the application of protocols based on imaging techniques (i.e. uv fluorescence, visible induced luminescence-vil) integrated with data obtained from single spot techniques such as x-ray fluorescence (xrf), fibre optic reflectance spectroscopy (fors) and total reflection infrared spectroscopy (tr ftir), provides high-quality information. in this paper some examples of analyses conducted in different contexts from museums to archaeological sites will be presented. these analyses are included in a wider research project aimed to enlighten the use of colours on the sculptures in ancient time and to better define materials used in the past . keywords ancient stone, polychromy, integrated protocols, archeometry received 08 april 2019; revised 21 may 2019; accepted 06 june 2019 citation: bracci, s., magrini, d., & bartolozzi, g. (2019). painted or not painted? discovering color traces of ancient stones. color culture and science journal, 11(1), 47–56. https://doi.org/10.23738/ccsj.110106 painted or not painted? discovering color traces of ancient stones 48 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110106 1. introduction in recent years, a strong interest about the residual polychromy on marble statuary emerged. although many ancient civilizations used polychromy on stone sculptures and architectural elements, today only a few, almost invisible, traces of these colours survive. as a result of these losses, in the minds of a very large majority of people, sculpture and monuments are considered not to have been coloured since their creation. understanding ancient polychromy is indeed a crucial issue since the lack of attention to this theme leads to a significant misunderstanding of both the artwork itself and of the artistic culture it represents. a correct reading of the original aspect of an artwork is often difficult due to the small amount and condition of the colour remainings. this is linked to the vicissitudes the sculptures underwent over the centuries, such as exposure to harsh environment or burial. in some cases, the polychromy did survive over the centuries, only to be extensively removed after hasty archaeological excavations, in order to reveal the neoclassical white «pure form» of the sculpture. the debate on the polychromy of ancient sculpture was already active in the nineteenth and early twentieth century, but only in 1982 it did a breakthrough in the studies with the research project initiated by von graeve on the polychromy of ancient sculptures (von graeve 1985). from then on, the issue of colour received a growing interest. in archaeology, a rising importance was given to the role of colour in understanding ancient cultures. furthermore, the technological development of noninvasive or micro-invasive tools supported these emerging archaeological ideas with archaeometric studies. these new studies and collaborations were particularly evident starting from the travelling exhibition bunte götter, munich (2003-2004); i colori del bianco, rome (2004); classicolor, copenhagen (2004). this exhibition was born by the collaboration among v. brinkmann, j. østergaard and p. liverani (brinkmann and wünsche 2004), pioneering scholars in this field. this high-profile exhibition of painted greek and roman casts, carefully studied and reconstructed by experts from across europe, attracted extensive media attention and turned out a renewed interest in sculptural polychromy in both popular and academic circles. this international initiative set the scene for a number of important projects, leading to a very noticeable increase in documentation and publications (giachi et al. 2007, liverani 2009, liverani and santamaria 2014). 2. methodological approach the archaeometric studies allow gathering information about the material composition and the state of conservation of polychrome marble artworks. the small amount of these coloured traces lead to a new approach for their characterization. in addition, since traces of polychromy are rare and fragile survivals, non-invasive methods are always preferable. in this way, the residues of polychromy remain intact for future generations. fig. 1: visible (left) and vil (right) images of marble mock-ups painted with different pigments (tempera): m=malachite; c=cobalt blue; .a=azurite; s=smalt; hb= han blue; l=lapis lazuli; hp= han purple; i=indigo; m=maya blue; b= egyptian blue. painted or not painted? discovering color traces of ancient stones 49 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110106 a non-invasive approach permits the examination of a very large number of artworks with a virtually limitless number of analytical acquisitions allowing to perform measurements in situ. already during the measurement process, this approach leads to a fundamental exchange of views among scientists, archaeologists, conservators and art hystorians. the non-invasive scientific protocol proposed, is characterized by the combination of complementary analytical techniques. the procedure strarted with a preliminary documentation of the surfaces by means of multiband imaging. this survey is based on photographic techniques using different radiations (fischer and kakoulli 2006, dyer and sotiropoulou 2017, dyer et al. 2013, cosentino 2014). uv fluorescence (uvf) (or more correctly, ultraviolet-induced visible luminescence (uvl) was used to spatially characterize the presence of organic and inorganic materials. visible induced infrared luminescence (vil) was used to locate and identify the blue pigment egyptian blue. vil is a photographic technique developed at the british museum in 2009 that can detect the egyptian blue which is a calcium-copper based pigment (cacusi4o10) (accorsi et al. 2009, verri 2009). egyptian blue is often preserved in extremely small quantities in the porous surfaces of ancient objects, which makes it hard – if not impossible – to identify the pigment even with a microscope. the pigment has, however, the unique property of absorbing visible light and emitting it as infrared radiation. the luminescence emitted by the pigment grains can be recorded with an infrared camera. the technique thus exploits the powerful emission identifying single particles of egyptian blue, which would be otherwise undetectable (verri 2010). the luminescence phenomenon is illustrated in figure 1 where the image in visible light and the vil image of marble mock-ups painted with different blue/green pigments are compared. the white glow represents egyptian blue (b) and two chinese pigments (han blue and han purple) while the others pigments almost disappeared. the efficacy of a multi-analytical approach is evident in figure 2 in which an area of a decoration on a sarcophagus with tiny trace of polychromy is investigated under different wavelengths and filters combinations (iannaccone et al. 2015). addressed by the imaging results, analyses by x-ray fluorescence spectroscopy (xrf) (karidas et al. 2006, shugar 2012 ), uv-vis reflectance spectroscopy (fors) (bacci 2000) and total reflection infrared spectroscopy (tr-ftir) (miliani et al. 2012) are performed in order to gain molecular and elemental information on a wide range of inorganic and organic painting materials, including most pigments, colorants and binders (iannaccone et al. 2015, liverani et al. 2017). today, despite important results achieved within the last few years, research on ancient polychromy is still at an early stage and shows some obvious limitations pertaining to the transferability of methodologies or findings (gasanova 2018). some interdisciplinary teams already integrate analytical and archaeological competences. one example is the work done at the ny carlsberg glyptotek in copenhagen, within the framework of the tracking colour project (østergaard 2010). in the published reports (ny carlsberg glyptotek 2013), a multidisciplinary approach to study a large group of materials is highlighted. the same approach, a collaboration with archaeometric competencies and the archaeological ones, drove our researches in the last years (iannaccone et al. 2015, liverani et al. 2017, noferi 2017). in this paper some examples of findings in different contexts from museums to archaeological sites will be presented. fig. 2: example of application of imaging technique on a polychrome marble sarcophagus. a) visible image; b) uv image where the fluorescence of red lake is visible; c) vil image where egyptian blue particles (not visible at naked eye) are instead clearly visible. painted or not painted? discovering color traces of ancient stones 50 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110106 2.1 technical information multiband imaging (uv and vil) for the investigation two camera were used: a canon eos 7d with a resolution of 18 megapixel and a modified canon eos 400d with a resolution of 10.10 megapixel. both cameras mounted a canon efs 18-135 mm f/3,55,6 is lens with different filters on varying of every photographic technique applied. different filters were applied also on the two flashes quantum qflash t5dr thus providing the proper radiation. fiber optics reflectance spectroscopy (fors) fors spectra were acquired in the range 350-900 nm using an ocean optics (mod. usb2000) instrument, equipped with optic fibers and a tungsten lamp as source. all the measurements were performed with 2x45°/0° configuration, allowing to work in diffuse reflectance by collecting the light scattered at 45° with respect to the incident light (avoiding specular reflected light) from an area of 2 mm in diameter. each acquired spectrum is the average of 30 acquisitions. a spectralon © tag was used as reference. fourier transform total reflection infrared spectroscopy (tr ft-ir) infrared measurements were carried out by means of a portable bruker optics alpha ft-ir spectrometer equipped with sic globar source and a dtgs detector. all spectra were acquired in total reflection mode, collecting 128 scans, with a resolution of 4 cm -1 on the 7500-375 cm -1 range and a measuring spot of 5 mm in diameter. the collected ir spectra were processed using opus 7.0.122 software. x-ray fluorescence (xrf) for x-ray fluorescence measurements, a portable xrf spectrometer (bruker, tracer iii sd) with micro x-ray tube with rhodium anode was used. the analysis was performed in the following conditions: 40 kev 12 µa. the irradiated area was about 12 mm 2 . the spectrometer was equipped with an sdd detector (fwhm < 145 ev at 100.000 cps) cooled with a peltier cell. acquisition time for each spectrum was 60 s. 3.examples of colour traces studies 3.1. catacombs the first case-study here presented is a sarcophagus with strigilated lateral parts and a central scene depicting two figures (a male and a female and several other objects and animals). it is preserved in the catacomb of st. pamphilus, on the via salaria vetus, at the deepest level. fig. 3: visible (left) and uv fluorescence (right) images of red lake on olimpus antistianus and irene. painted or not painted? discovering color traces of ancient stones 51 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110106 fig. 4: visible (a,c) and vil (b,d) images of some details of the antistianus sarcophagus in the slab showing the dextrarum iunctio between olympus antistianus and his wife octavia irene, the surface revealed traces of red and blue colours, slightly visible to the naked eye, especially on the robes and the altar. all the red traces showed a characteristic ultraviolet pink-orange fluorescence (fig. 3) that it is usually associated with red lake pigments such as madder lake enabling to hypothesize the use of a red lake for creating the red details. analyses using the vil technique revealed the presence of egyptian blue in some specific part of the bas relief such as the basin or the pillar of the flame (fig. 4). data acquired with other spot techniques (xrf, fors) confirmed the findings and the hypothesis drawn by observing uvf (data not shown) and vil images. in this case, micro-climatic conditions of the catacombs are suitable for the preservation of colours on stone. painted or not painted? discovering color traces of ancient stones 52 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110106 temperature and humidity are constant and the lighting is limited to the duration of either visits or inspections. these conditions facilitate the conservation of polychromy, allowing deep investigations that can highlight important details about the technique used by the old master painters. 3.2. outdoor and indoor statuary etruscan gens statlane’s sarcophagi, are part of the florence national archaeological museum collection, currently preserved in the courtyard of villa corsini, located close to sesto fiorentino. these sarcophagi are dated back to the first half of the third century bc. the group consists of ten sarcophagi. among all the sarcophagi, only the vil survey performed on sarcophagus of vel statlane (fig. 5) highlighted an interesting residue of egyptian blue on the lower part otherwise not visible at naked eye. conversely, the sarcophagus belonging to ramtha ziltna (fig.6), is the only one, among those analysed, showing the presence of red lake. the characteristic red/pinkish fluorescence, under uv light, appears on the belt and the ribbon of the woman portrayed on the lid. fors spectra acquired on this area confirmed this hypothesis. fig. 5: sarcophagus of vel statlane, son of sethi, 275-250 bc, villa corsini, florence (left) and vil image of a detail of the lower slab (right). fig. 6: tomb ii, female sarcophagus of ramtha ziltna, 260-50 bc, villa corsini, florence (a), visible (b) and uv fluorescence (c) images of the detail of the ribbon. painted or not painted? discovering color traces of ancient stones 53 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110106 fig. 7: headless cuirassed emperor (a) at the archaeological museum of grosseto, macro image of residual gold (b) and vil detail of the cuirass (c). on other sarcophagi belonging to this group also traces of red and yellow ochres were identified (data not shown). the rare traces, almost invisible, discovered during the study did not allow us to establish with certainty the extent of polychromy, but for sure the sarcophagi were painted. this is also confirmed by the documentation of the excavation and by the observations painted or not painted? discovering color traces of ancient stones 54 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110106 of scholars shortly after the excavation. the sarcophagi were always described as polychrome artifacts. the poor conservation of polychromy may be correlated to the lithotype used (nenfro stone, tuff), that is coarse and prone to disaggregation but also to the stressful conservative history. indeed, after the excavation, at the beginning of 20 th century, the sarcophagi were displayed in the courtyard of the museum, exposed to light and rain for more than 50 years, where in 1966 they also suffered the dreadful event of the flooding in florence. 3.3. excavated statuary an interesting example of residual polychromy is represented by the headless cuirassed emperor (fig. 7a), belonging to early imperial cycle from the augusteum of rusellae (roselle, grosseto) exposed in the archaeological museum of grosseto. tiny traces of gold have been discovered on the drapery (fig. 7b), and traces of egyptian blue survived on the cuirass (fig. 7c). also in this case few traces of colour/decoration were identified but they were enough to confirm the practice of painted and coloured statues. even in this case the poor conservation of polychromy, apart from other reasons, is surely closely related to conservative history. from documents found during the study it emerged that after the excavation (in the 1950s) the statues were cleaned by immersing them in tanks with sodium hypochlorite and "heavily brushed" to remove the excavation earth. 4. virtual reconstruction of the ancient colour digital reconstruction of ancient polychromy is a relatively recent issue in the history of archaeological and architectural heritage documentation. it emerged as a result of new interest in the experimental archaeology and the technological development of computer graphic tools. the standard research activity has been recently supported by the development of experimental approaches, often based on digital technologies to propose and assess reconstruction hypotheses. those hypothetical reconstructions of the original colours and decorations, previously exemplified on physical replicas of objects, are now moving to the digital media. they are usually reproduced on digital photorealistic threedimensional models, obtained with scanning technologies (siotto et al. 2014). the colour reconstructions, based on the results of scientific analysis and archaeological data, allow the visualization of the original appearance of the artwork helping scholars to understand how and why colour was used to decorate or finish the artworks. anyway, the reconstruction of the original polychromy is not yet a consolidated subject of research; a lot of work still has to be done to improve our knowledge of the methods and techniques of colour application on polychrome artworks (østergaard 2010). in addition, the virtual reconstruction becomes more difficult in the context of ancient polychromy, because just tiny and deteriorated samples are usually found. today, meshlab software (meshlab 2019) was used to support the polychrome reconstruction stage and blender (blender python api 2019) (or, rather, a combination of meshlab and blender) was used to achieve a more sophisticated visual presentation of the current and reconstruction ancient colour (siotto et al. 2015). previous projects tried to realistically simulate the original colour of the works of art. an interesting example was the one supervised by prof. paolo liverani, which returned a 3d model of the augusto di prima porta at vatican museum, complete with its decorative apparatus (liverani 2004). in 2002, the stone restoration laboratory of the vatican museums started a careful and painstaking cleaning which has brought back to light many traces of colour that were no longer visible. to understand the nature and the composition of the pigments, they were subjected to a scientific examination by analytical techniques. the results of these investigations showed that colours were applied on the clothing, on details of the armour, on the hair and on details of the eyes but not on the skin or on the ground of the armour. on the basis of these evidences, a complete reconstruction of the colours was prepared on a plaster cast. the surviving traces are sufficient to permit the colours to be reconstructed over most of the surface. the missing parts were supplemented in a hypothetical manner based on the logic of the use of colours on the statue and on comparisons with roughly contemporary portraits (liverani 2011). 5. conclusions the detailed knowledge of an artwork or archaeological artefact, in terms of its composition, is a prerequisite condition for any research in art history or archaeology as well as for any conservation-restoration procedure. the scientific approach here presented represents a strategic tool for achieving a complete awareness of the residual polychromy on ancient statuary; it will open up new understanding of original polychromy, supporting more painted or not painted? discovering color traces of ancient stones 55 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110106 correct and conscious restoration procedures (e.g. in the case of the archaeological excavations or programmatic operations in the museum collections). the aim is to develop a broader awareness of residual polychromy to be shared with the research groups active in this field on the national and international scene, with the museums and institutions involved in conservation of cultural heritage and for educational purposes with non-specialist public. the technical examination is based on the use of several non-invasive methods. in this way, a very large number of artworks with a virtually limitless number of analytical acquisitions can be analysed. this approach leads also both to the reduction of the sampling activity and to a fundamental exchange of views among scientists, archaeologist, conservators and art hystorians already during the measurement process. one still open issue is represented by the assessment of the reliability of the digital colour reconstructions. until now it has not been possible to create realistic renderings that take into account the effect of colour with the material (marble or other supports) and light. further improvement could be dedicated to testing the actual system to assess the effectiveness and limitations to recreate a hypothesis of the original colour (on the digital reconstruction). very often the extent of the surviving pigments/colour is too small to allow a satisfactory reconstruction of original appearance. the latter is a combination of several parameters, such as pigments but also binders, thickness, preparation layers, etc.) that are not always known. so the reconstruction is something very risky that can easily turn into a modern reinterpretation. 6. conflict of interest declaration all authors states that there is no conflict of interest. 7. funding source declaration the authors declare that no funding was received neither in the course of the study nor during the assembly of the manuscript. 8. acknowledgments the authors would like to acknowledge paolo liverani for the collaboration on the cuirassed emperor and the olimpo antistianus sarcophagus. for the latter we thanks barbara mazzei responsible of the commission of sacred archeology of the vatican for the access to catacombs. claudia noferi, carlotta cianferoni of the national archeological museum in florence for the access to the etruscan sarcophagy. 9. short biography of the authors susanna bracci she is senior researcher at icvbccnr. she is leading the icvbc mobile laboratory for the in-situ diagnostics of works of art including paintings, frescoes and glasses (mosaics and stained glass windows). in this framework special attention is devoted to the color traces on statues and architecture. donata magrini she is a conservation scientist at icvbc-cnr. her research activity is mainly aimed at investigating methodologies for diagnosis and monitoring the state of conservation of cultural heritage, with special attention to paintings, frescoes and stones. in this context, she is involved in the application of non-invasive techniques (uv-vis-nir spectroscopy, xrf, ft-ir and imaging) to study residuals of original polychromy on stone. giovanni bartolozzi he is a conservation scientist at ifac-cnr. his research activity is focused on the diagnostic for cultural heritage (wall paintings, easel and canvas paintings, contemporary artworks). he is expert in both non invasive and invasive spectroscopic techniques (fors, uv-vis-nir, ft-ir). references accorsi, g. verri, g. bolognesi, m. armaroli, n. clementi, c. miliani, c. romani, a. 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(2015), ‘ancient polychromy: study and virtual reconstruction using open source tools’ in acm journal on computing and cultural heritage (jocch) 8, 3, 16: pp. 1-20. verri g. (2009) ‘the spatial resolved characterization of egyptian blue, han blue and han purple by photo-induced luminescence digital imaging’, analytical and bioanalytical chemistry 394(4), pp. 1011-1021. verri g., (2010), ‘the ‘treu head’: a case study in roman sculptural polychromy’, the british museum technical research bulletin, 4, pp. 39-54. von graeve, v., (1985) ‘marmobilder aus herculaneum und pompeji’, in ricerche di pittura ellenistica, quaderni dei dialoghi di archeologia 149, rome, pp. 227-251. cultura e scienza del colore color culture and science 10 18 riv is ta s em es tr al e | h al fye ar ly jo ur na l | d o i: 10 .2 37 38 /c c sj .0 0 rivista dell’associazione italiana colore www.gruppodelcolore.it doi: 10.23738/ccsj.i102018.00 cultura e scienza del colore color culture and science 10numero 10 dicembre 2018 number 10 december 2018cultura e scienza del colorecolor culture and science rivista semestrale dell’associazione italiana colore http://jcolore.gruppodelcolore.it/ issn 2384-9568 doi: 10.23738/ccsj.00 ance e227716 direttore responsabile | editor-in-chief maurizio rossi (politecnico di milano, it) redazione | associate editors aldo bottoli (b&b colordesign, it) daria casciani (politecnico di milano, it) marco gaiani (università di bologna, it) silvia piardi (politecnico di milano, it) alessandro rizzi | deputy editor (università degli studi di milano, it) francesca valan (studio valan, it) vien cheung (university of leeds, uk) editorial board members john barbur (city university london, uk) giovanni bartolozzi (ifaccnr, it) berit bergstrom (ncs colour ab, se) giulio bertagna (b&b colordesign, it) janet best (natific, uk) aldo bottoli (b&b colordesign, it) patrick callet (école centrale paris, fr) jean-luc capron (université catholique de louvain, be) daria casciani (politecnico di milano, it) vien cheung (university of leeds, uk) paula csillag (espm university, br) osvaldo da pos (università degli studi di padova, it) hélène declermont-gallernade (chanel parfum beauté, fr) reiner eschbach (xerox, usa) alessandro farini (ino-cnr, it) christine fernandez-maloigne (university of poitiers, fr) renato figini (konica-minolta sensing europe, eu) raffaella fontana (ino-cnr, it) davide gadia (università degli studi di milano, it) marco gaiani (alma mater studiorum università di bologna, it) robert hirschler (serviço nacional de aprendizagem industrial, br) takahiko horiuchi (chiba university, jp) sandra krasovec (fashion institute of technology, usa) francisco imai (canon, usa) lia luzzatto (color and colors, it) kevin mansfield (ucl, uk) veronica marchiafava (gdc-associazione italiana colore, it) cultura e scienza del colore color culture and science rivista dell’associazione italiana colore registrazione presso il tribunale di milano al n. 233 del 24.06.2014 gabriel marcu (apple, usa) anna marotta (politecnico di torino, it) manuel melgosa (universidad de granada, es) anna grazia mignani (ifac-cnr, it) annie mollard-desfour (cnrs, fr) maria luisa musso (universidad de buenos aires, ra) galina paramei (liverpool hope university, uk) laurence pauliac (historienne de l’art et de l’architecture, paris, fr) silvia piardi (politecnico di milano, it) marcello picollo (ifac-cnr, it) renata pompas (afol milano-moda, it) boris pretzel (victoria & albert museum, uk) noel richard (university of poitiers, fr) katia ripamonti (cambridge research system, uk) alessandro rizzi (università degli studi di milano, it) maurizio rossi (politecnico di milano, it) jodi l. sandford (università di perugia, it) raimondo schettini (università degli studi di milano bicocca, it) verena m. schindler (chair aic s.g. environmental colour design) gabriele simone (renesas electronics europe gmbh, de) andrea siniscalco (politecnico di milano, it) ferenc szabó (university of pannonia, hu) mari uusküla (tallinn university, ee) francesca valan (studio valan, it) ralf weber (technische universität dresden, de) stephen westland (university of leeds, uk) alexander wilkie (charles university in prague, cz) peer review process tutti gli articoli inviati alla rivista “cultura e scienza del colore color culture and science” sono sottoposti ad un processo di revisione secondo la seguente procedura: prima revisione gli associate editor valutano ogni articolo per determinare se il tema e il contenuto sono di interesse per la rivista. una volta valutati gli articoli, gli associate editor selezionano dei revisori scegliendoli nell’editorial board in base all’esperienza degli stessi in un particolare settore disciplinare o tematica. seconda revisione ogni articolo è revisionato da due o tre revisori in un processo in cui essi stessi e gli autori sono mantenuti anonimi. ai revisori è chiesto di valutare l’articolo considerando la sua originalità, la metodologia applicata e l’impatto sulla ricerca o sulla pratica professionale. dopo aver raccolto i commenti dei revisori, gli associate editor elaborano e inviano al direttore responsabile un giudizio riassuntivo sull’accettazione o meno dell’articolo. collaboratori | contributors laura bellia, meriem benkhedda, giulio bertagna, ute besenecker, barbara blinbarrois, aldo bottoli, john bullough, giorgio buratti, guihua cui, osvaldo da pos, hélène de clermont-gallerande, julie deydier, chiara donzella, patrick doucet, eszter dudás, francesca fragliasso, robert gerlach, min huang, ted krueger, michela lecca, changjun li, ming ronnier luo, maria martone, annamaria mauro, anna mazzanti, manuel melgosa, maria kirk mikkelsen, claudio oleari, massimo osanna, pietro paglierani, floriana papa, pedro j. pardo, zachary pearson, renata pompas, nicolas rolland, michela rossi, gennaro spada, emanuela stefanizzi, kheira tabet aoul, justyna tarajko-kowalska, francesca valan, anne varichon, ágnes urbin editore | publisher gruppo del colore – associazione italiana colore www.gruppodelcolore.it sede legale: piazza carlo caneva, 4 20154 milano (italia) all articles submitted to “cultura e scienza del colore color culture and science” journal are peer-reviewed according to the following procedure: first review the associate editors evaluate each article in order to define if the topic and content is suitable for consideration by the journal. once the article passes the initial review, the associate editors select several referees in the editorial board based on their expertise in the particular field or topic. second review each article is reviewed by two or three referees under a double-blind peer review process where the authors and the reviewers are kept anonymous. referees are asked to evaluate the manuscript based on its originality, methodology and impact to research and relevance to the professional practice. after collecting the referees’ reports, the associate editors make a recommendation on the acceptability of the article to the editor in chief. doi: 10.23738/ccsj.i102018.00 gruppo del colore associazione italiana colore sommario | summary10 5 7 13 21 31 43 49 59 67 77 87 93 editorial by maurizio rossi color on ceramics in the medieval architecture of tlemcen, algeria: light, ambiance and symbolism by meriem benkhedda and kheira tabet aoul the experience of equivalent luminous colors at architectural scale by ute besenecker, ted krueger, john bullough, zachary pearson, robert gerlach the changing colour of chanel’s lipstick ranges from 1960 to 2015 by hélène de clermont-gallerande, nicolas rolland, patrick doucet, julie deydier, anne varichon, barbara blin-barrois light and colors in the “villa dei misteri” by laura bellia, massimo osanna, gennaro spada, annamaria mauro, chiara donzella, francesca fragliasso, emanuela stefanizzi a colour palette methodology by maria kirk mikkelsen blue color traditions in polish wooden architecture – valuable cultural heritage and a source of inspiration by justyna tarajko-kowalska is it possible to improve the weighting function for lightness in the ciede2000 color-difference formula? by manuel melgosa, guihua cui, claudio oleari, pedro j. pardo, min huang, changjun li, ming ronnier luo from decoration to industrial design: gio ponti and color in architectural innovation by michela rossi and giorgio buratti the contribution of colour in the artistic representation of the sacred. italian innovations from the end of xix century to the first part of the xx century by anna mazzanti improvement of a lamp construction with a highly reflective material by eszter dudás and ágnes urbin a digital framework for color design and education by pietro paglierani and francesca valan colors, lights and shapes in the naples underground. the “art stations” of line 1 colori, luci e forme nell’underground napoletano. le “stazioni dell’arte” della linea 1 by maria martone and floriana papa colours for slancio. project of the scene for a service and care facility in monza colori per slancio. progetto della scena per una struttura di assistenza e cura a monza by giulio bertagna and aldo bottoli review by renata pompas communications and comments by michela lecca and osvaldo da pos sommario | summary10 103 119 129 132 columns 5 cultura e scienza del colore color culture and science | 10 | 2018 issn 2384-9568 editorial by publishing the n. 10 the “color culture and science journal” has reached its fifth year of life. after a process that lasted almost two years, the magazine was recognized as “scientific” by the anvur for the area 08 “civil engineering and architecture” and the area 10 “sciences of antiquity, philological-literary and historical-artistic”. for three years the magazine has been publishing only articles in english or bilingual. the ethical code, the peer review process and the detailed instructions for authors are available on the website. each article is indexed by a doi code and the dates of reception, review and acceptance of each published article are declared, in addition to any sources of funding and any conflicts of interest. all of these criteria were applied for the journal to be included in the emerging sources citation index (esci) of web of science (wos) for which we applied at the beginning of 2018 and we are awaiting a response. the journal is published by a multidisciplinary association that has its points of reference in the themes of color, light and the linked technicalscientific, cultural and professional sectors. also in this issue there is a clear example of multidisciplinary integration. in the paper “color on ceramics in the medieval architecture of tlemcen, algeria: light, ambiance and symbolism“, the authors meriem benkhedda and kheira tabet aoul explore through a cultural and historical analysis the ancestral know-how and demonstrate that this architectural heritage has a colorful atmosphere, whose evolution is linked to the relationship between shapes, lights, materials and colors as well as its sociocultural context. in the article “the experience of equivalent luminous colors at architectural scale”, ute besenecker, ted krueger, john bullough, zachary pearson and robert gerlach present a research in the context of lighting and perception, through several experiments at architectural scale to explore whether visual stimuli closely matched for chromaticity and light level would produce recognizable differences in perceived and intuitive qualities. the topic of color in cosmetics, in the ncs color space defining hue, blackness and chromaticness of lipsticks, is the core of the scientific research “the changing colour of chanel’s lipstick ranges from 1960 to 2015” presented by hélène de clermont-gallerande, nicolas rolland, patrick doucet, julie deydier, anne varichon and barbara blin-barrois. laura bellia, massimo osanna, gennaro spada, annamaria mauro, chiara donzella, francesca fragliasso and emanuela stefanizzi, in their research “light and colors in the villa dei misteri”, analyze the lighting conditions and performed a metrological survey of the fresco’s colors in the triclinium of this ancient roman villa in pompeii. in the paper “a colour palette methodology”, maria kirk mikkelsen presents a method in design teaching for the creation of color palette called color combination cards which is divided into four categories: plan, create, adjust and review. justyna tarajko-kowalska presents a study “blue color traditions in polish wooden architecture – valuable cultural heritage and a source of inspiration” about the use of the blue color in the traditional polish wooden architecture, considering its symbolic, functional and decorative aspects. manuel melgosa, guihua cui, claudio oleari, pedro j. pardo, min huang, changjun li, and ming ronnier luo, in the metrological research “is it possible to improve the weighting function for lightness in the ciede2000 color-difference formula?”, compare the performance of the δe 00 colordifference formula with three modified formulas, applying the recommendations of the cie 217:2016. using the methods of investigation of the representation, michela rossi and giorgio buratti in their article “from decoration to industrial design: gio ponti and colour in architectural innovation”, focus on the role of color in ponti’s design works: ceramics, furnishing accessories, domestic interior and building elements in the period 1940-59. in the essay “the contribution of colour in the artistic representation of the sacred. italian innovations from the end of xix century to the first part of the xx century”, through a historical analysis, anna mazzanti delves into the theme of color, that assumes a symbolic value, in the context of the sacred painting between the nineteenth and twentieth centuries in italy. eszter dudás and ágnes urbin in the paper “improvement of a lamp construction with a highly reflective material” present a case study of lighting product design of a car indoor lamp focusing on the efficiency and the homogeneous light distribution of the product. in the paper “a digital framework for color design and education” pietro paglierani and francesca valan present an interesting set of digital functions, named “colortools”, collected in a single framework written in python, implementing the most popular color-theory libraries to match the needs of color designers. maria martone and floriana papa, in their paper “colors, lights and shapes in the naples underground. the art stations of line 1”, analyze and document the chromatic 6 cultura e scienza del colore color culture and science | 10 | 2018 issn 2384-9568 aspects of some of the main art stations, through the tools of investigation of the representation, defining an underground color sampling guide of spaces without natural light. finally, giulio bertagna and aldo bottoli in their article “colours for slancio project of the scene for a service and care facility in monza” present the interesting results of a color design research on the perceptual configuration of the new facility for vegetative states, minimal consciousness, coma and als of the san pietro di monza centre. in the columns, renata pompas presents the review of the book of andrea dall’asta “la luce splendore del vero. percorsi tra arte, architettura e teologia. percorsi dall’età paleocristiana al barocco the light splendour of truth. paths among art, architecture and theology from early christian to baroque”. michela lecca with osvaldo da pos in their communications and comments report some considerations from the talk that prof. da pos gave during the munsell 2018 international congress, about various topics on the subject of “food and color”. the editor in chief maurizio rossi 35 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110104 the tropical aquarium: a case of polychrome decoration in the architecture of the early 1900s carlo giannattasio 1 1 department of civil, architectural and environmental engineering, university of naples federico ii, naples, italy. carlo.giannattasio@unina.it. corresponding author: carlo giannattasio 1 (carlo.giannattasio@unina.it) abstract the study involved the analysis of the polychrome ceramic decoration of the tropical aquarium, a building located inside the mostra d’oltremare in naples. the ornamentation was created by the majolica factory ceramica di posillipo, and specifically by paolo ricci, an eclectic artist of the 1900s. the use of stereoscopic photogrammetry allowed to survey the work as a whole, identifying the main colours used while also preserving the three-dimensionality of the relief figures. the study focused on the definition of the work's stylistic and chromatic features, aiming at the preservation of its decorative setup. keywords ornament, ceramic tiles, mostra d’oltremare received 30 march 2019; revised 04 may 2019; accepted 18 june 2019 citation: giannattasio, c. (2019). the tropical aquarium: a case of polychrome decoration in the architecture of the early 1900s. color culture and science journal, 11(1), 35–40. https://doi.org/10.23738/ccsj.110104 the tropical aquarium: a case of polychrome decoration in the architecture of the early 1900s 36 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110104 1. introduction colour has always been a characterizing and fundamental element in architecture, be it used for decoration or for different purposes. however, at the beginning of the 20th century, with the rationalist movement, the purity of shapes and geometries was preferred to the use of colour and decorations. in many cases, in fact, these assume a more marginal role, sometimes going so far as to be completely excluded from architecture. such a style also caught on in italy, where its canons sometimes underwent different influences, linked to the cultural and traditional context. in naples, for example, at the mostra d’oltremare exhibition center, polychrome ceramic wall tiles are used, both indoors and outdoors. the study focused on the analysis of the decoration on the vestibule of one of the exhibition buildings, i.e. the tropical aquarium. its design was entrusted to architect carlo cocchia, while the polychrome majolica decoration was created by paolo ricci of the ceramica di posillipo factory. the threedimensional decoration was reconstructed using stereoscopic digital photogrammetry and subsequently analyzed in order to define the main hues and stylistic features typical of the abovementioned building. 2. a look into the life of paolo ricci an eclectic author of apulian origin, paolo ricci was born in barletta in 1908 and moved to naples to study in 1918. here, in addition to developing a marxist, antifascist view, he came into contact with the thriving neapolitan artistic scene of the time, meeting vincenzo gemito first in 1923, and then luigi crisconio in 1927. in 1929, he approached the circumvisionist group, without becoming directly involved in it. here, he met carlo cocchia, with whom he collaborated on the mostra di oltremare e del lavoro italiano nel mondo for the creation of the work at hand. also in 1929, along with guglielmo peirce and carlo bernari, he wrote the manifesto of the unione distruttivisti attivisti (uda), thus coming into contact with the avantgardes. between 1930 and 1931, during a period in paris, he delved into themes and connections with contemporary artists such as pablo picasso, piet mondrian, ossip zadkine, le corbusier and others. over the years, he exhibited at the first rome quadriennale (1931) in many editions of the sindacali campane. in 1938, he began working with the majolica factory ceramiche di posillipo, founded the previous year by patron giuseppina de feo, engineer paolo marone and sculptor antonio de val. the factory became a meeting point for neapolitan artists of the time such as carlo cocchia, edoardo giordano, aniello antonio mascolo and others. also noteworthy is ricci's communist and anti-fascist political ideology, which led him to be arrested on two different occasions (1932, 1943), and his relationship with contemporary intellectuals who used to gather at villa lucia, including benedetto croce, alfonso gatto and many others. foreign artists and authors of international caliber were also frequently hosted in the villa, such as david alfaro siqueiros, nicolás guillén, pablo neruda and others. at the end of the second world war, ricci began writing for several newspapers, including la voce and l'unità, and took part in several international exhibitions: the venice biennale (1948, 1950, 1952), the rome quadriennale (1948, 1951,1955, 1959, 1965); he also exhibited in prague in 1949 and in berlin in 1951. in the post-war period, he further collaborated with architects carlo cocchia and luigi cosenza. ricci died in 1986, after a long and artistic career and a copious critical and literary production. 3. the mostra d’oltremare: birth and decline commissioned by mussolini in 1936 and provided for in the 1936-39 general urban development plan (prg) written by luigi piccinato, the fairground of the mostra delle terre italiane di oltremare was born in 1937 to host the esposizione tematica universale. in particular, the first triennial exhibition revolved on the celebration of the regime's colonial policy. contemporary to the neapolitan fairgrounds is the parco dell'esposizione universale di roma, later named eur, in whose project piccinato himself was involved. over a million square meters were planned for the creation of the naples compound and construction was completed in just sixteen months. part of the surface allotted in the prg remains unused, but was nevertheless reserved for future developments. in fact, the area was supposed to host the exhibition lavoro fig. 1. view of the main front of tropical aquarium. the building currently hosts the boccioni art school. the tropical aquarium: a case of polychrome decoration in the architecture of the early 1900s 37 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110104 degli italiani d'oltremare. various architects of the naples region participated in the design of the pavilions, including carlo cocchia, who oversaw the restaurantpool complex and the well-known fontana dell'esedra, in addition to the building under examination. the exhibition was inaugurated in 1940 and closed after only one month following italy's entry into the war. the damage caused by the bombing was considerable and a rebuilding of the compound was necessary in the early 1950s. in 1952, the first mostra triennale del lavoro italiano nel mondo was inaugurated and the mostra d'oltremare had a new image that united two souls, one more rationalist and one more traditional. it is currently in a state of total neglect. 4. analysis of the work the present study focuses on the analysis of the decoration placed on the vestibule of the tropical aquarium. designed by carlo cocchia, the facility was built in 1938 as a complement to the villa comunale's aquarium. the volume is regular and square, in line with the dictates of the rationalist movement. the anonymity of the building is interrupted by a polychrome representation in ceramic tiles placed on the main elevation (8.10m high and 10.75m wide). the covering was manufactured by the ceramiche di posillipo factory, but the design and construction were carried out by paolo ricci, a friend and colleague of carlo cocchia. the composition depicts a marine scene, portraying real and fantastic figures, including seahorses, fishes, mermaids and tritons. these representations are typical of ceramiche di posillipo in particular, and of the campanian tradition in general. 4.1. working methodology in order to best define the formal and stylistic peculiarities of the work in question, a photogrammetric survey was carried out. the digital stereoscopic photogrammetry process has allowed us to obtain a three-dimensional result, both in terms of point cloud and structured mesh, and to keep the colourimetric information intact. the 3d model was used to build orthophotos, so that the metric information of the complex could also be preserved. thus, it was possible to best define the colours used and stylistic features. 4.2. colourimetric features the dynamism of the scene is created by the alternation between flat drawings and three-dimensional figures realized through the mezzotondo technique. however, the most important aspect of the work is undoubtedly the use of colour. in fact, while the building appears as a white polyhedron, the vestibule is completely detached from the rest by way of its polychromy. at a first analysis of the work, it can be seen that five colours were used: blue, yellow and red, white and copper green. if the choice of the first four shades of color may depend on an influence that ricci had during a contact with the authors of de stijl, the green copper is a distinctive sign of ceramiche di posillipo, as can be seen in other works by the same factory, and of campanian tradition in general. it should be added, however, that the color shades used are many, unlike neoplasticism where the use of color was limited to a single shade. fig. 2. colourimetric features. on the left, the orthophoto of the façade, obtained by digital photogrammetry. on the right, the main color tones used within the composition. 4.3. composition of the work the composition in its entirety is depicted on 25 x 25 cm tiles forming an orthogonal grid. leaving out the threedimensional figures, the grid thus formed makes it possible to detect the prevalent colours and their function in the scene: while white mainly functions as foundation on which the other colours rest or mix, copper green is used to define the work's outline. the three-dimensional figures do not respect such regularity in the single tile, as the figures' plasticity does not allow the definition of all the tropical aquarium: a case of polychrome decoration in the architecture of the early 1900s 38 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110104 fig. 3. composition of the work. on the top, the orthophoto of the façade without the three-dimensional figures; on the center, the orthophoto of the façade only with the three-dimensional figures. on the bottom, the orthophoto of the façade of the building. the pieces within the predetermined measure. if, however, the figures are added to the pre-established study grid, it can be seen that a good number of them are in copper green. this color is not therefore relegated to being the mere frame of the work, but has the function of expressing the dynamism and complexity of the whole facade. one should also dwell on ricci's stylistic choice. the style of the flat tiles is typical of the ceramiche di posillipo factory, while the three-dimensional figures conform to the modern movements and artistic groups of the time. during his trip to paris, ricci was probably influenced by contemporary authors such as pablo picasso or ossip zadkine (think, for example, of the stylized figures reminding of a cubist and abstract fashion). finally, one must consider the importance of naples as a cultural and innovative center in the first half of the 1900s. among the artists who visited the city in the first half of the century is also david alfaro siqueiros, who was a guest at villa lucia. siqueiros was an exponent of mexican muralism, a movement within which some analogies with the work in question can be found. these include the use of primary colours, main figures in relief, compact walls without openings. consider for example the mural "el pueblo a la universidad, la universidad al pueblo" (1952 1956) by siquieros himself, on the facade of the rectorate of the universidad nacional autónoma de méxico in mexico city: the building was declared "artistic monument of the nation" in 2005. fig. 4. view of the work of david alfaro siqueiros "el pueblo a la universidad, la universidad al pueblo" (1952 1956) (source: wikimedia commons). the tropical aquarium: a case of polychrome decoration in the architecture of the early 1900s 39 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110104 5. conclusions paolo ricci's tropical aquarium is a masterpiece in its complexity and originality. first of all, the work intends to detach itself from the rationalist movement: the ornament is not superfluous but an integral part of the building, being a representation of the function of the building itself. secondly, the complex loses its anonymity through the juxtaposition of a polychrome ceramic decoration, typical of the campanian tradition, on the vestibule. such a design choice infused new life to the material: from captive and recluse within the walls, it breaks out free and becomes the center of the work itself. this solution was also used later by paolo solieri in vietri sul mare for the design of the solimene factory: the front of it is in fact covered with circular modular elements in orange and copper green, as used by ricci in the tropical aquarium. the artist designed a work of extraordinary beauty using polychrome ceramics, creating a decorated prospectus that at the same time breaks with the traditional stylistic canons for the representation of two-dimensional and three-dimensional figures. the tropical aquarium's current state of conservation of is precarious, as can be seen from the loss of material and the discontinuities in the composition. due to its uniqueness and peculiarity, paolo ricci's work should be safeguarded, protected and valorized before it is irreversibly lost. conflict of interest declaration the author declares that there is no actual or potential conflict of interest including financial, personal or other relationships with other people or organizations within three years of beginning the submitted work that could inappropriately influence or be perceived to influence his work. funding source declaration the author declares that he is a phd student with a fellowship at university of naples federico ii. short biography of the author carlo giannattasio phd student with a fellowship at university of naples federico ii. he graduated in architectural engineering at university of salerno, italy, and in architecture at universidad nacional de córdoba, argentina. fig. 5. view of the main front of the solimene factory in vietri sul mare, designed by paolo solieri. the tropical aquarium: a case of polychrome decoration in the architecture of the early 1900s 40 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110104 references napolitano g. (2003) ‘la ceramica di posillipo, 1937-1947: un viaggio nell'immaginario e nella memoria della città di napoli nella prima metà del novecento, salerno: provincia’, assessorato ai beni culturali, turismo e spettacolo; raito, vietri sul mare: centro studi salernitani raffaele guariglia, pp 39 89. giordano p. (1994) ‘napoli guide di architettura moderna’, roma: officina edizioni, xxvii xxx, pp. 42 45, 54 57. ricci p. (1987) ‘paolo ricci: opere dal 1926 al 1974’, napoli: electa. franco m., ricci d. (2008), "paolo ricci", napoli: electa. siola u. (1990) ‘la mostra d'oltremare e fuorigrotta", roma: electa, 1990. stenti s., cappiello v. (1998) ‘napoli guida: 14 itinerari di architettura moderna’, napoli: clean, 1998, pp 116 129. fratta a. (2004) ‘il patrimonio architettonico dell'ateneo fridericiano’, napoli: arte tipografica. vv.aa. (1941) ‘architettura i mostra delle terre italiane d'oltremare fascicolo monografico’, n 1/2, milano. mollo l. (2011) ‘note su architettura e tecnica della mostra delle terre italiane d'oltremare a napoli’, aversa, capri: atti del ix forum internazionale le vie del mercante s.a.v.e. heritage. caterina g., nunziata m. (1987) ‘carlo cocchia cinquant’anni di architettura 1937-1987’ genova: sagep editrice. carpiceci m. (2012) ‘fotografia digitale e architettura’, roma: aracne. giordano m., barba s. (2012) ‘le geometrie del decoro architettonico’, fisciano: cues, pp 79-146. https://www.storiacity.it/guide/707-acquario-tropicale-di-fuorigrotta-anapoli http://www.napoliontheroad.com/pesacanepadiglioni3.htm https://upload.wikimedia.org/wikipedia/commons/6/69/el_pueblo_a_la_ universidad%2c_la_universidad_al_pueblo.jpg cultura e scienza del colore color culture and science 05 16 riv is ta s em es tr al e | h al fye ar ly jo ur na l | d o i: 10 .2 37 38 /c c sj .0 0 rivista dell’associazione italiana colore www.gruppodelcolore.it doi: 10.23738/ccsj.i52016.00 cultura e scienza del colore color culture and science special issue on food colour editor: anna grazia mignani alessandro farini http://www.gruppodelcolore.it 05numero 05 febbraio 2016 number 05 february 2016 collaboratori | contributors daria casciani, paul chambers, trevor cox, kyoko hidaka, lucie ling, marina mastropietro von rautenkrantz, fulvio musante, maria luisa musso, marianne patera, anna poli, maurizio rossi editore | publisher gruppo del colore – associazione italiana colore www.gruppodelcolore.it sede legale: piazza carlo caneva, 4 20154 milano (italia) doi: 10.23738/ccsj.i52016.00 gruppo del colore associazione italiana colore cultura e scienza del colore color culture and science rivista dell’associazione italiana colore registrazione presso il tribunale di milano al n. 233 del 24.06.2014 peer review process tutti gli articoli inviati alla rivista “cultura e scienza del colore color culture and science” sono sottoposti ad un processo di revisione secondo la seguente procedura: prima revisione gli associate editors valutano ogni articolo per determinare se il tema e il contenuto sono di interesse per la rivista “cultura e scienza del colore color culture and science”. una volta valutati gli articoli, gli associate editors selezionano una serie di revisori scegliendoli scegliendoli nell’editorial board in base all’esperienza degli stessi in un particolare settore disciplinare o tema. seconda revisione ogni articolo è revisionato da due revisori in un processo in cui essi stessi e gli autori sono mantenuti anonimi. ai revisori è chiesto di valutare l’articolo considerando la sua originalità, la metodologia applicata e l’impatto sulla ricerca o sulla pratica professionale. dopo aver raccolto i commenti dei revisori, gli associate editors elaborano ed inviano al direttore responsabile un giudizio riassuntivo sull’accettazione o meno dell’articolo. all articles submitted to “cultura e scienza del colore color culture and science” journal are peer-reviewed according to the following procedure: first review the associate editors evaluates each article in order to define if the topic and content is suitable for consideration by the “cultura e scienza del colore color culture and science” journal. once the article passes the initial review, the associate editors select several referees in the editorial board based on their expertise in the particular field or topic second review each article is reviewed by two or three referees under a double-blind peer review process where the authors and the reviewers are kept anonymous. referees are asked to evaluate the manuscript based on its originality, methodology and impact to research and relevance to the professional practice. after collecting the referees’ reports, the associate editors makes a recommendation on the acceptability of the article to the editor in chief. cultura e scienza del colore color culture and science rivista semestrale dell’associazione italiana colore http://jcolore.gruppodelcolore.it/ issn 2384-9568 doi: 10.23738/ccsj.00 direttore responsabile | editor-in-chief maurizio rossi (politecnico di milano, it) redazione | associate editors aldo bottoli (b&b colordesign, it) daria casciani (politecnico di milano, it) alessandro farini (inoa-cnr, it) davide gadia | deputy editor (università degli studi di milano, it) marco gaiani (università di bologna, it) editorial board members john barbur (city university london, uk) berit bergstrom (ncs colour ab, se) giulio bertagna (b&b colordesign, it) janet best (natific, uk) aldo bottoli (b&b colordesign, it) patrick callet (école centrale paris, fr) jean-luc capron (université catholique de louvain, be) daria casciani (politecnico di milano, it) osvaldo da pos (università degli studi di padova, it) bepi de mario (crasmi, it) hélène declermont-gallernade (chanel parfum beauté, fr) reiner eschbach (xerox, usa) alessandro farini (ino-cnr, it) christine fernandez-maloigne (university of poitiers, fr) renato figini (konica-minolta, eu) davide gadia (università degli studi di milano, it) marco gaiani (università di bologna, it) robert hirschler (serviço nacional de aprendizagem industrial, br) sandra krasovec (fashion institute of technology, usa) francisco imai (canon, usa) lia luzzatto (color and colors, it) kevin mansfield (ucl, uk) veronica marchiafava (associazione italiana colore, it) gabriel marcu (apple, usa) anna marotta (politecnico di torino, it) manuel melgosa (universidad de granada, es) anna grazia mignani (ifac-cnr, it) annie mollard-desfour (cnrs, fr) maria luisa musso (universidad de buenos aires, ra) claudio oleari (università degli studi di parma, it) galina paramei (liverpool hope university, uk) laurence pauliac (historienne de l’art et de l’architecture, paris, fr) silvia piardi (politecnico di milano, it) marcello picollo (ifac-cnr, it) renata pompas (afol milano-moda, it) boris pretzel (victoria & albert museum, uk) noel richard (university of poitiers, fr) katia ripamonti (cambridge research system, uk) alessandro rizzi (università degli studi di milano, it) maurizio rossi (politecnico di milano, it) jodi l. sandford (università di perugia, it) raimondo schettini (università degli studi di milano bicocca, it) gabriele simone (st microelectronics, it) andrea siniscalco (politecnico di milano, it) ferenc szabó (university of pannonia, hu) mari uusküla (tallinn university, ee) francesca valan (studio valan, it) ralf weber (technische universität dresden, de) alexander wilkie (charles university in prague, cz) veronica marchiafava (associazione italiana colore, it) anna grazia mignani (ifac-cnr, it) silvia piardi (politecnico di milano, it) alessandro rizzi (università degli studi di milano, it) francesca valan (studio valan, it) http://www.gruppodelcolore.it sommario | summary05 5 7 15 21 31 41 49 55 numero 05 febbraio 2016 number 05 february 2016 editorial by alessandro farini and anna grazia mignani a comparison of color schemes and images in the package design of sweets in the us and japan by kyoko hidaka colour as a code in food packaging: an argentine case by maria luisa musso colour in food packaging strategies and rules by marina mastropietro von rautenkrantz domestic horticultural centric lighting design by daria casciani, fulvio musante, maurizio rossi tea versus celadon: some chromatic interactions by lucie ling a look into cross-modal associations between taste, color and music by paul chambers, marianne patera, trevor cox food perception without colors by anna poli cultura e scienza del colore color culture and science | special issue on food color | 05 | 2016 4 issn 2384-9568 this page has been intentionally left white cultura e scienza del colore color culture and science | special issue on food color | 05 | 2016 5 issn 2384-9568 editorial 2015 was a very important year for food culture because in milan took place the universal exposition expo 2015. expo 2015 was held under the theme feeding the planet, energy for life. it was very natural, for an international journal based in italy to dedicate a special issue to the relationship between food and colour. as editors of this special issue, we took into consideration the statement of the famous gastronome savarin: “tell me what you eat, and i’ll tell you who you are”, since the many color hues related to food are indeed an expression of culture, in addition to being nutritional and health aspects. we could imagine that food is a huge topic, and obviously we know very well that colour is also an interdisciplinary topic. what we could not forecast is the incredible extent of the subjects belonging to the overlap between food and colour. in this special issue, only to give same examples, you can find papers about tea, packaging, lighting, music. finding referees for so many different topics was not easy, because we need in a referee the same overlap in expertise present in the papers. for this reason, the preparation of this special issue was not fast as we would have liked and we want to apologize with all the authors. we want also to thank maurizio rossi, editor in chief of this journal, for his proposal to us to be editors of this special issue, and veronica marchiafava, journal secretariat, for her patience, continuous commitment, and great help. without veronica this special issue would not exist. and now enjoy the read, or, probably better for this special issue, “bon appetit”! editor alessandro farini (inoa-cnr, it) anna grazia mignani (ifac-cnr, it) special issue on food colour cultura e scienza del colore color culture and science 47 cultura e scienza del colore color culture and science | 08 | 2017 issn 2384-9568 anna luana tallarita info@annaluanatallarita.com utad/iade/grupo de geociancias the meanings of the red abstract femininity is strongly linked to the symbolism of red as a color tied to fertility and blood that is poured into life for conception and not for death. symbol to the feminine world, one thinks of the many heroines of rosamunda’s fairy tales in snow white, from the lovely sleeping to little red riding hood, all have the red color symbol.the red symbol of the fire of the holy spirit also inspiresand infuses knowledge of the apostles, the color of fire is a symbol of knowledge, think of the myth of prometheús that brings the fire to the men and the apple of the tree of knowledge in ‘eden that is red as red is the god of genesis called: lord of fire. red is linked to war because it is the color that metal takes when it is placed in the furnace, in fact the choice to identify with the name of mars the red-colored planet is due to iron oxides prevalent on its surface. keywords femininity, red, symbol, knowledge citation: tallarita a. l. (2017) ‘the meanings of the red’, cultura e scienza del colore color culture and science journal, 08, pp. 47-52, doi: 10.23738/ccsj.i82017.04 received 20 june 2016; revised 30 may 2017; accepted 31 may 2017 italian translation provided: ‘le significazioni del rosso’ anna luana tallarita jazz singer, composer, anthropologist and creative artist working in different forms to express a colored complex intercultural reality. published writing, disks, videos, plasticworks, and worked throughout europe and south america and lives between lisbon and milan. in 1999-2017 (2015 phd) she studied at the italy france e portugal. member: utad-iade-geoscience group. 48 cultura e scienza del colore color culture and science | 08 | 2017 | 47 52 tallarita a.l. issn 2384-9568 doi: 10.23738/ccsj.i82017.04 1. the feminine and the red red is linked to war because it is the color that metal takes when it is placed in the furnace, in fact the choice to identify with the name of mars the red-colored planet is due to iron oxides prevalent on its surface. in the alchemical symbolism one of the phases of the alchemical process is red: rubedo, so called for the high temperatures during this time. it represents sulfur and with the white color symbolizing mercury forms a pair of opposites whose union is called: alchemical weddings (foschi, 2000). in the myths inherent in the creation of the world, red is present, for example, in genesis where the individual is molded with red clay (gen.1, 26; 2,7), in fact, adam means the soil, reddish ground: adamah with the semitic root ‘dm be red. the myths are followed by historical epochs and different cultures by assuming the vital and mortal connotations of this archetypal color. symbolism is sung in the myths of every corner where humanity is present, in terms of color and, in particular, red. in the mesothotic myth of tiamat, the goddess is cut off because blood can make the earth fertile for animal creations. in the red-blooded hodiod theogony, giants were born, within a symbology where blood spill was conceived only through ritual actions. femininity is strongly linked to the symbolism of red as a color tied to fertility and blood that is poured into life for conception and not for death. until the 19th century. the wedding dress was red [1], where the female red is a symbol of the cave, the uterus. red is the carnation symbol of diana, the goddess of hunting, loved by a young pastor before seduced him and then abandoned him to despair and from those tears flowers originated precisely carnations characterized by a spicy and sensual aroma. even the christian tradition links the tears of mary at the foot of the cross the birth of red carnations. in irish myths is linked to the symbol of red water, the banshee [2], a legendary creature with eyes always red because of tears. it is noted that red is very related to the feminine world, one thinks of the many heroines of rosamunda’s fairy tales in snow white, from the lovely sleeping to little red riding hood, all have the red color symbol. the symbology associated with red apple, a true manifestation of pomegranate, for example in snow white’s story, is the transition to the fertility stage of the woman and the appearance of the red blood. as the myth of persephone staying in the kingdom of the dead is the representation of the woman who becomes fertile, in the myth the pomegranate [3] will be the symbol that will force her to stay in the kingdom of the dead. but medusa’s myth is aimed at the appearance of fertility, where red is in that case a symbol of life, fertility and rebirth. 1. il femmineo e il rosso il rosso è legato alla guerra perché è il colore che il metallo assume quando è posto nella fornace, infatti la scelta di identificare con il nome di marte il pianeta dal colore rosso è dovuto agli ossidi di ferro prevalenti sulla sua superficie. nel simbolismo alchemico una delle fasi del processo alchemico è del colore rosso: la rubedo, così chiamata per le alte temperature durante questo raggiunte. rappresenta lo zolfo e con il colore bianco che simboleggia il mercurio forma una coppia di opposti la cui unione viene denominata: nozze alchemiche (foschi, 2000). nei miti inerenti la creazione del mondo il rosso è presente ad esempio nella genesi dove l’individuo è plasmato con argilla rossa (gen.1, 26;2,7), infatti adamo significa del suolo, terra rossastra: adamah con la radice semitica ‘dm essere rosso. i miti si susseguono per epoche storiche e culture diverse assumendo le connotazioni vitali e mortali di questo colore-archetipo. la simbologia si sussegue tramandata nei miti di ogni angolo dove l’umanità sia presente, per quello che riguarda il colore e in particolare il rosso. nel mito mesopotamico di tiamat la dea si fa tagliare la testa perchè il sangue possa rendere fertile la terra per la creazioni degli animali. nella teogonia di esiodo dal sangue rosso nacquero i giganti, entro una simbologia dove il versamento del sangue è concepito solo attraverso azioni rituali. la femminilità è fortemente connessa alla simbologia del rosso, in quanto colore legato alla fertilità e al sangue che si versa per la vita per il concepimento e non per la morte. fino al xix sec. l’abito da sposa era rosso [1], dove il rosso femminile è simbolo della caverna, dell’utero. rosso è il garofano simbolo di diana dea della caccia, che amata da un giovane pastore prima lo seduce e poi lo abbandona alla disperazione e dalle cui lacrime nacquero dei fiori appunto i garofani caratterizzati da un aroma speziato e sensuale. anche la tradizione cristiana collega alle lacrime di maria ai piedi della croce la nascita dei garofani rossi. nei miti irlandesi è legata al simbolo dell’acqua rossa la banshee [2], leggendaria creatura dagli occhi sempre rossi per via delle continue lacrime. si nota come il rosso sia molto legato al mondo femminile, si pensi alle tante eroine delle fiabe da rosamunda a biancaneve, dalla bella addormentata a cappuccetto rosso tutte hanno come simbolo il colore rosso. la simbologia legata alla mela rossa [3], manifesto in vero del melograno, presente ad esempio nella storia di biancaneve rappresenta il passaggio alla fase della fertilità per la donna e la comparsa del mestruo che è rosso-sangue appunto. come il mito di persefone che soggiorna nel regno dei morti è la rappresentazione della donna che diventa fertile, nel mito sarà il melograno 49 cultura e scienza del colore color culture and science | 08 | 2017 | 47 52 the meanings of the red issn 2384-9568 2. from phoenix to shamanic rituals: meaning red the red symbol of the fire of the holy spirit also inspires and infuses knowledge of the apostles, the color of fire is a symbol of knowledge, think of the myth of prometheús [4] that brings the fire to the men and the apple of the tree of knowledge in ‘eden that is red as red is the god of genesis called: lord of fire. moses will see him as an ardent tree of a red and perpetual fire [5]. red is the color that strongly characterizes china and is largely present in its mythology. huo-pu’s, the minister of fire, has red hair and beard, which is nevertheless represented by the arab phoenix [6] rising from the ashes of its red fire, whose precept is post fata resurgo [7] that after death comes back to rise. one of the greek names to say red is, in fact, φοινικοῦς, -ῆ, -οῦν foinikus, a symbol of the followers of the sun god which it represents. the phoenix [8] has a beautiful plumage made of red feathers in the body and rosy pens to cover a part of the blue tail, wings are purple and gold as the neck in its iconic representation in the imagination of the myth that characterizes it [9]. the arabian phoenix [10], symbol of death and resurrection is also associated with osiris, the figure of jesus christ and the holy spirit, which is fire and light symbolized by red as the ceremonial color present in many religions [11]. the poet and writer dante alighieri will describe it as follows: [...] that the phoenix more and more resurfaces, when at the fifteenth appressed grass drifts in its life does not pass, but incense salt of tears and amomo, and nard and myrrh are the last bands. (hell xxiv, 107-111). the magical-religious shamanic rituals of many cultures have in their foundations the presence of red color; shamanic is defined as a series of ritual complexes present in different cultural contexts, by chronology and geographical position, characterized by a series of specific rituals and symbolic common traits (mastromattei, 1995). in these rituals, blood plays a role of considerable importance, either physically used or with substitute elements that represent it through its red color, resulting in the use of red ocher [12]. various shamanic traditions have contact with blood as a triggering of initiatory illness that comes as a result of symptoms and phenomena that reveals itself in an individual’s life without warning, making him a shaman. initiations and rites of passage are everywhere associated with isolation and suffering, symbol of death and ritual rebirth. the shaman inviting spirits to nourish his body and blood leads back to the bond he establishes il simbolo che la costringerà al soggiorno nel regno dei morti. ma il mito di medusa si rivolge alla comparsa della fertilità, dove il rosso in tal caso è simbolo di vita, di fertilità e di rinascita. 2. dalla fenice ai rituali sciamanici il rosso-simbolo del fuoco dello spirito santo inspira altresì il sapere e infonde la conoscenza sugli apostoli, il colore del fuoco è simbolo della conoscenza, si pensi al mito di prometheús [4] che porta il fuoco agli uomini e alla mela dell’albero della conoscenza nell’eden che è rossa come rosso è il dio della genesi denominato: signore del fuoco. mosè lo vedrà come un albero ardente di un fuoco rosso e perpetuo [5]. il rosso è il colore che fortemente caratterizza la cina e ampiamente presente nella sua mitologia. huo-pu dai capelli e la barba rossi è il ministro del fuoco, questo è nondimeno rappresentato dall’araba fenice [6] che rinasce dalle ceneri del proprio fuoco rosso, il cui precetto è post fata resurgo dopo la morte torno ad alzarmi [7]. uno dei nomi greci per dire rosso infatti è φοινικοῦς, -ῆ, -οῦν foinikus, simbolo dei seguaci del dio sole che appunto rappresenta [8]. la fenice ha uno splendido piumaggio fatto da piume rosse nel corpo e penne rosee a ricoprire una parte della coda azzurra, le ali sono di porpora e oro come il collo nella sua rappresentazione iconica nell’immaginario del mito che la caratterizza [9]. l’araba fenice simbolo della morte e risurrezione [10] è associata altresì ad osiride, alla figura di gesù cristo e allo spirito santo che è fuoco e luce simboleggiata dal rosso quale colore cerimoniale presente in numerose religioni [11]. il poeta e scrittore dante alighieri così la descriverà: [...] che la fenice more e poi rinasce, quando al cinquecentesimo appressa erba ne biada in sua vita non pasce, ma sol d’incenso lacrima e d’amomo, e nardo e mirra son l’ultime fasce. (inferno xxiv, 107-111). i rituali sciamanici magico-religiosi di molte culture hanno come fondamento la presenza del colore rosso; sono definiti sciamanici una serie di complessi rituali presenti in contesti culturali differenti tra loro, per cronologia e posizione geografica, caratterizzati una serie di tratti specifici rituali e simbolici comuni (mastromattei, 1995). in questi rituali il sangue ricopre un ruolo di notevole importanza, adoperato materialmente o con elementi sostitutivi che lo rappresentino attraverso ll suo colore che è rosso, riconducendo all’uso dell’ocra rossa [12]. diverse tradizioni sciamaniche, presentano il contatto con il sangue come scatenante della 50 cultura e scienza del colore color culture and science | 08 | 2017 | 47 52 tallarita a.l. issn 2384-9568 doi: 10.23738/ccsj.i82017.04 with them at the time of initiation. the concept of pure and impure is vital in this initial trauma of the initiatory process and subsequent shamanic profession, where blood and its representation through red is one of the magic substances for excellence (propp, 1976). this color tied to the shamans is found manifest in some southsiberian (marrazzi, 1984) turkish songs, the blood often recurs, reciting a few lines: black lake formed by the tears of the eyes, red lake formed by the blood of the chest [13]. according to rong culture, for example, the demon that infects the house is urged to move away inviting him to drink red blood and eat red meat to leave and leave the house free. in nepal, between the tamang, at the end of a ritual in honor of the spirits of the clan, a dough of rice, the flesh and blood of a red cock sacrificed for the occasion was offered to the spirits of the dead. for dharmaphala in magical rituals, a blood supply is symbolically performed with a cup filled with a colored red liquid that represents it (de nebeskj-wojkowitz, 1975). funding this research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. conflict of interest i don’t have actual or potential conflicts of interest, including financial, personal or other relationships with other persons or organizations within three years after the commencement of the work submitted, which may unduly influence or be perceived to influence the work. notes [1] the queen victoria at his wetsuit for the white with the orange holes. white in india is the habit of widows in many parts of africa is the color of mourning, the twentieth malattia iniziatica che si presenta a seguito di sintomi e fenomeni che svelandosi nella vita di un individuo senza alcun preavviso, ne fanno uno sciamano. iniziazioni e riti di passaggio sono ovunque associati a isolamento e sofferenza, simbolo di morte e rinascita rituale. lo sciamano che invita gli spiriti a nutrirsi del suo corpo e del suo sangue riconduce al legame che egli instaura con questi al momento dell’iniziazione. il concetto di puro ed impuro è vitale in questo trauma iniziale del processo iniziatico e della successiva professione sciamanica, dove il sangue e la sua rappresentazione attraverso il colore rosso è una delle sostanze magiche per eccellenza (propp, 1976). questo colore legato agli sciamani lo si ritrova manifesto in alcuni canti turchi sud-siberiani (marrazzi, 1984) il sangue ricorre sovente, recitano alcuni versi: nero lago formato dalle lacrime degli occhi, rosso lago formato dal sangue del petto [13]. in base alla cultura rong ad esempio il demone che infesta la casa è pregato ad allontanarsi invitandolo a bere il sangue rosso e mangiare la carne rossa per andar via e lasciar la casa libera. in nepal tra i tamang al termine di un rito in onore degli spiriti del clan un impasto di riso, carne e sangue di un gallo rosso sacrificato per l’occasione veniva offerto agli spiriti dei morti. per i dharmaphala nei rituali magici si esegue simbolicamente una offerta di sangue con una coppa riempita di un liquido colorato di rosso che lo rappresenta (de nebeskj-wojkowitz, 1975). note [1] la regina vittoria alle sue muta per il bianco con i fori d’arancio. quello bianco in india è l’abito delle vedove in molte parti dell’africa è il colore del lutto, il ventesimo sec lo impone caduto il costume della verginità. [2] la banshee più famosa si chiamava aibhill e proteggeva gli òbrien. stando alla leggenda, nel 1014 il re brian boru si gettò nella battaglia di clontarf pur sapendo di andare incontro a morte certa, dal momento che la notte precedente aibhill gli era apparsa mentre lavava i panni dei soldati finché l’acqua non si tingeva completamente figure 1 oil and acrylic paint on canvas and various materials:from left to right la donna and le maschere. al.tallarita 2014. figura 1 pitture olio e acrilici su tela e vari materiali. da sinistra a destra la donna e le maschere. al.tallarita 2014. 51 cultura e scienza del colore color culture and science | 08 | 2017 | 47 52 the meanings of the red issn 2384-9568 century imposes the fall of the costume of virginity. [2] the most famous banshee was called aibhill and protected òbrien. according to the legend, in 1014 king brian boru threw himself into the battle of clontarf, knowing that he was going to meet certain death, since the previous night aibhill had appeared to him as he was washing the soldiers until the water was completely dyed of blood vermilion color [3] the symbolism of the apple is related to pomegranate. domain symbolism on the world sometimes takes on an erotic value. among the most noteworthy symbols are the apple eaten by adam and eve but with controversial explanations the boss of discord that would give rise to the war of troy after the judgment of paris the pies of the elders guarded by a dragon in a garden at the confines of the world , the mystical apples that give the name to avalon island of apples, the poisoned apple offered by the stepmother in snow white and the one put by william tell on her son’s head. remember the boss of mystery discord in which the apple engraved to the most beautiful, thrown by eris, goddess of discord, on the table of the wedding banquet of peleo and teti, the cause of the dispute between era, aphrodite and athena. zeus resigned to parid prince of troy, who voted for aphrodite, who had promised elena’s love, and that was the cause of the war that had arisen. also golden apple is an element that appears in some myths and legends as well as in the stories of nordic literature. in the painting on the theme of the artist edward burne-jones (1833-1898), the garden of the hesperides 1869-1873 painted the esperides dressed in red. [4] prometheús friend of men, devised a stratagem to drive the gods the privilege of the fire. he challenged the inevitable revenge of the gods to shine the darkness of humanity. he was punished by zeus, but not tamed in his emotional intent, though he was punished hard on the cliff and devoured by the birds of prey. [5] moses in the old testament. chapter iii of the exodus, god calls mose on mount oreb, from the middle of a bush burning alive, but without consuming he hears the voice of god who tells him the job of saving the jews from slavery in egypt. on that occasion, god confides to moses his name: i am he who am (exodus 3. 14). [6] the ancient egyptians were the first to speak of bennu, who then became greek in the greek legends. in egypt it was usually depicted with the atef crown or with the solar disk emblem. for the egyptians it was a sparrow, for the first dynasties or a herd of herons, nor did it resurface from the flames but from the waters. [7] in greek myths but not only was a fabulous sacred bird, it looked like a real eagle the ancients identified it with the golden pheasant and the bible, with ibis or peacock. others, with the pink heron or cinereo heron. the volatile to represent it is the garzetta which is similar to heron. as a symbol of the rising and setting sun, the phoenix was presiding over the royal jubilee. collies that re-emerged for the first time, was associated with the planet venus star of the morning, a manifestation of the resurrected ishiris. [8] this represented ba’s soul of the sun god ra, of which he was the hieroglyphic emblem. [9] a long tapered beak, long paws, two long feathers, a rose and a blue sliding softly down the head or erect on the top of the head and three long feathers hanging from the tail pierced a rose, a blue and a red-fire. [10] every morning at dawn he bathed in the water and sang such a wonderful song that the sun god stole his boat or his chariot in greek mythology to hear it. every 500 del colore vermiglio del sangue. [3] la simbologia della mela è legata al melograno. simbolo del dominio sul mondo, assume talvolta una valenza erotica. tra le simbologie più note si ricordano la mela mangiata da adamo ed eva ma con spiegazioni controverse il pomo della discordia che avrebbe dato origine alla guerra di troia dopo il giudizio di paride i pomi delle esperidi custodite da un drago in un giardino ai confini del mondo, le mele mistiche che danno il nome ad avalon isola delle mele, la mela avvelenata offerta dalla matrigna a biancaneve e quella posta da guglielmo tell sulla testa del proprio figlio. si ricordi il pomo della discordia mito in cui la mela incisa alla più bella, lanciata da eris, dea della discordia, sul tavolo del banchetto di matrimonio di peleo e teti, causa della lite fra era, afrodite e atena. zeus si astenne fu chiesto a paride principe di troia, che votà per afrodite che le aveva promesso l’amore di elena, e cio fu causa della guerra che si scatenò. inoltre la mela d’oro è un elemento che appare in alcuni miti e leggende come anche nei racconti della letteratura nordica. nel quadro sul tema l’artista edward burne-jones (1833–1898) the garden of the hesperides 1869-1873 dipinge le esperidi vestite di rosso. [4] prometheús amico degli uomini, escogitò uno stratagemma per carpire agli dèi il privilegio del fuoco. egli sfidò l’inevitabile vendetta degli dèi per rischiarare le tenebre dell’umanità. fu punito da zeus, ma no domati nel suo intento emotivo, se pur duramente punito sulla rupe e divorato dai rapaci. [5] mosè nel vecchio testamento. iii capitolo dell’esodo, dio chiama mose sul monte oreb, dal mezzo di un cespuglio che bruciava a fuoco vivo, ma senza consumarsi egli ode la voce di dio che gli comunica l’incarico di salvare gli ebrei dalla schiavitù in egitto. in quella occasione dio confida a mose il suo nome: io sono colui che sono (esodo 3. 14). [6] gli antichi egizi furono i primi a parlare del bennu, che poi nelle leggende greche divenne la fenice. in egitto era solitamente raffigurata con la corona atef o con l’emblema del disco solare. per gli egizi era un passero, per le prime dinastie o ad un airone cenerino, inoltre non risorgeva dalle fiamme ma dalle acque. [7] nei miti greci ma non solo era un uccello sacro favoloso, aveva l’aspetto di un’aquila reale gli antichi la identificavano col fagiano dorato e nella bibbia, con l’ibis o col pavone. altri, con l’airone rosato o l’airone cinereo. il volatile idoneo a rappresentarla è la garzetta che è simile all’airone. quale simbolo del sole che sorge e tramonta, la fenice presiedeva al giubileo regale. colei che ri-sorge per prima, venne associata al pianeta venere stella del mattino, manifestazione dell’osiride risorto. [8] questa rappresentava l’anima ba del dio del sole ra, di cui era l’emblema in geroglifico. [9] un lungo becco affusolato, lunghe zampe due lunghe piume una rosa ed una azzurra che le scivolano morbidamente giù dal capo o erette sulla sommità del capo e tre lunghe piume che pendono dalla coda piumata una rosea, una azzurra e una color rosso-fuoco. [10] ogni mattina all’alba faceva il bagno nell’acqua e cantava una canzone così meravigliosa che il dio del sole arrestava la sua barca o il suo carro, nella mitologia greca, per ascoltarla. ogni 500 anni, la fenice sentiva sopraggiungere la sua morte si ritirava in un luogo appartato e costruiva un nido sulla cima di una quercia o di una palma. qui accatastava le più pregiate piante balsamiche con le quali intrecciava un nido a forma di uovo, grande quanto era in grado di trasportarlo (cosa che stabiliva per prove ed errori) . infine vi si adagiava, 52 cultura e scienza del colore color culture and science | 08 | 2017 | 47 52 tallarita a.l. issn 2384-9568 doi: 10.23738/ccsj.i82017.04 years, the phoenix felt his death come to a secluded place and built a nest on the top of an oak or palm tree. here she packed the most valuable balsamic plants with which she had an egg-shaped nest, as large as she was able to carry it (which she established for tests and mistakes). finally he lay down, let the rays of the sun burn him, and let himself be consumed by his own flames. because of the cinnamon and myrrh that burns, the death of a phoenix is often accompanied by a pleasing fragrance. a small larvae (or an egg) emerged from the cumulus of ash, which the sun’s rays grew rapidly until transformed into the new phoenix in three days, after which the young and powerful phoenix flared to eliopoli and lay above it ‘sacred tree, it is also said that from the throat of the phoenix came the breath of life as reported by cheremone stoic philosopher initiated in egyptian mysteries or by orapollo lived under zenone. phenicism is one of the manifestations of the sun as interpreted by sordon, bearing a late handwriting of the name osiris consisting of an eye and a scepter. [11] it tells the myth of creation that phoenix was the vital force that originated from the aquatic chaos on the primordial hill at the origin of times. it is said that the bennu created himself from the fire that burned on the summit of the sacred willow of heliopolis. just as the sun is always the same and rises only after the previous sun has gone down, fenice always had one copy at a time. hence the appellativo sempre eradem: always the same. [12] the ocher: these are clay silica blends and iron oxides and / or hydroxides. from the geological point of view, ochers are secondary deposits formed by erosion from rocks of various kinds, enriched with ferrous base particles. while the simple use of color can be dated at least 400,000 years ago. the paintings dating back to at least 30,000 years ago, think of rock paintings in the caves of lascaux (southern france). around 80,000 years ago, finds at the blombos cave in two pieces of red ocher decorated with geometric motifs. beyond the blombos graffiti, the first and most important artistic expressions are undoubtedly considered the rock paintings created in the same caves. [13] quoted in the representation of the progeny of arlik qan, where the eldest arka solton, brings the smallpox and dwells in a lake. marazzi, u. testi dello sciamanismo, torino, utet, p.115 bibliography a.v. (2008). ‘esodo, bibbia’. roma, cei edizione. de nebeskj-wojkowitz, r. (1975) ‘oracles and demons of tibet: the cult and iconography of the tibetan protective deities’. gratz, akademische druck, pp. 343-344 foschi, v. (2000) ‘il simbolismo del colore rosso. titolo: centro studi la runa archivio di storia, tradizione, letteratura, filosofia’.[online], available: https://www.centrostudilaruna.it/simbolismodelrosso. html [accessed 31.05.2013]. marazzi, u. (1984) ‘testi dello sciamanismo’. turin, utet, p. 114 mastromattei, r. (1995) ‘tremore e potere roma’. franco angeli, pp. 27-28. propp, w. j. (1976) ‘le radici storiche dei racconti di magia’. roma, newton compton lasciava che i raggi del sole l’incendiassero, e si lasciava consumare dalle sue stesse fiamme. per via della cannella e della mirra che bruciano, la morte di una fenice è spesso accompagnata da un gradevole profumo. dal cumulo di cenere emergeva poi una piccola larva (o un uovo) , che i raggi solari facevano crescere rapidamente fino a trasformarla nella nuova fenice nell’arco di tre giorni, dopodiché la nuova fenice giovane e potente volava ad eliopoli e si posava sopra l’albero sacro, per altro si dice anche che dalla gola della fenice giunse il soffio della vita (il suono divino, la musica) che animò il dio. ma nella antica tradizione riportata da erodoto, la fenice risorge ogni 500 anni, come riportato da cheremone filosofo stoico iniziato ai misteri egizi o da orapollo vissuto sotto zenone. la fenice è una delle manifestazioni del sole come interpretato da sbordone che riporta una grafia tarda del nome di osiride costituita da un occhio e uno scettro. [11] narra il mito della creazione che la fenice fu la forza vitale che all’origine dei tempi sorse dal caos acquatico sulla collina primordiale. si dice infatti che il bennu abbia creato sé stesso dal fuoco che ardeva sulla sommità del sacro salice di eliopoli. proprio come il sole che è sempre lo stesso e risorge solo dopo che il sole precedente è tramontato, di fenice ne esisteva sempre un unico esemplare per volta. da qui l’appellativo semper eradem: sempre la medesima. [12] le ocre. si tratta di miscele di silice argilla e ossidi e/o idrossidi di ferro. dal punto di vista geologico le ocre sono depositi secondari formatisi per erosione da rocce di vario tipo, arricchiti di particelle a base ferrosa. mentre il semplice impiego del colore è databile ad almeno 400. 000 anni fa. le pitture risalenti ad almeno 30. 000 anni fa, si pensi alle pitture rupestri nelle grotte di lascaux (francia meridionale). a circa 80.000 anni fa risalgono i ritrovamenti presso la caverna di blombos in di due pezzi di ocra rossa decorati con motivi geometrici. al di là dei graffiti di blombos, le prime e più importanti espressioni artistiche sono senza dubbio da considerare le pitture rupestri, create nelle stesse grotte. [13] citato nella rappresentazione della progenie di arlik qan, dove il primogenito arka solton, porta il vaiolo e dimora in un lago. marazzi, u. testi dello sciamanismo, torino, utet,p.115 bibliografia a.v. (2008). ‘esodo, bibbia’. roma, cei edizione. de nebesky-wojkowitz, r. (1975) ‘oracles and demons of tibet: the cult and iconography of the tibetan protective deities’. graz,akademische druck-u verlagsanstalt. pp. 343-344 foschi v. (2000) ‘il simbolismo del colore rosso. titolo: centro studi la runa archivio di storia, tradizione, letteratura, filosofia’.[online], available: https://www.centrostudilaruna.it/simbolismodelrosso. html [accessed 31.05.2013]. marazzi, u. (1984) ‘testi dello sciamanismo’. torino, utet. p.114 mastromattei, r. (1995) ‘tremore e potere roma’. franco angeli. pp. 27-28. propp, w. j. (1976). ‘le radici storiche dei racconti di magia’, roma, newton compton. 53 cultura e scienza del colore color culture and science | 08 | 2017 issn 2384-9568 lynne bartlett lynnebartlettoriginals@ btinternet.com jewellery designer/maker an overview of the history of the use of colour in jewellery abstract from ancient times rare and beautiful coloured materials have been prized and worn as adornment and/or indications of status. in early societies these materials would have been ‘found’ objects such as shells and feathers but as technologies advanced metals were used extensively. for thousands of years jewellers created beautiful objects using a range of metals with limited colours: yellow, red and white. whether the yellow was high purity gold or bronze, or the white was silver, platinum or a base metal alloy, the visual impact was essentially the same. other materials were needed to expand the palette to colours such as blue, purple and green. this paper outlines the materials and methods that were used from the earliest known examples to recent decades. historically gemstones and vitreous enamels provided jewellers with a wide range of colours. the ancient egyptians used turquoise, lapis and coral with gold to produce vibrant multi-coloured jewellery. the romans had a particular fondness for emeralds, sapphires and pearls while the anglo-saxons produced amazing jewellery featuring red garnets and blue enamel. magnificent mediaeval jewels, mostly royal status symbols, incorporated rubies, emeralds, sapphires and diamonds with fine enamels. by the eighteenth century new sources of gemstones, particularly from s america, made jewellery more affordable and subject to changes in fashion. over the ensuing decades fashionable jewellery veered from almost monochrome, diamond-set designs to multi-coloured, multi-gemstone pieces. the victorians used an amazing array of gemstones, with rare and unusual species particularly prized. the mid-twentieth century saw the introduction of metals that could be coloured such as anodised aluminium and a new metal, titanium, which enabled jewellers to produce multi-coloured pieces without the use of gemstones or enamel. keywords colour, jewellery, gemstones, titanium, aluminium citation: bartlett l. (2017) ‘an overview of the history of the use of colour in jewellery’, cultura e scienza del colore color culture and science journal, 08, pp. 53-58, doi: 10.23738/ccsj.i82017.05 received 12 january 2017; revised 6 november 2017; accepted 15 november 2017 lynne bartlett is a jewellery designer/maker. having originally studied chemistry and worked for many years in the chemical industry, jewellery is her second career. the use of colour in jewellery has been a dominant theme in her work and she currently uses titanium and dyed anodised aluminium. her doctoral thesis at the university of the arts london (2010) studied the surface of coloured titanium. 54 cultura e scienza del colore color culture and science | 08 | 2017 | 53 58 bartlett l. issn 2384-9568 doi: 10.23738/ccsj.i82017.05 1. introduction from ancient times rare and beautiful coloured materials have been prized and worn as personal adornment, indication of status and/ or for supposed protective or amuletic purposes. this paper outlines the ways in which colour has been incorporated into jewellery from the earliest times to recent decades. consideration is given to the colours of the most commonly used metals, gemstones in various forms, vitreous enamel, anodised aluminium and, finally, the interference colours of titanium. however as an overview it is not possible to include information about the cultural significance of the colours used, the sources of the gemstones or more modern coloured materials such as plastic. of all the elemental metals only two, gold (yellow) and copper (red) are intrinsically coloured. all the others such as silver, iron, nickel, etc. are white or rather various shades of grey. regardless of the workability, strength or cost, the aesthetic appearance is equivalent. whether the yellow was high purity gold or bronze, or the white was silver, platinum or a base metal alloy, the visual impact was essentially the same. gold may be manipulated by alloying to produce a range of colours namely white, yellow, red and green but the variations are subtle. vibrant colours can only be introduced by the incorporation of other materials in a piece of jewellery and it is the range and use of these coloured materials such as gemstones and enamels that are the focus of this paper. but to cover such a vast subject means that only a glimpse of the methods and materials that have been used can be provided. examples have also been limited to europe and the ancient civilisation of the middle east that have most influenced the development of european jewellery. 2. early adornment in early societies ‘found’ objects such as shells, seeds and coloured stones were used as adornment and examples have been found in graves dating back to 30,000 bc (phillips, 1996). necklaces from ancient cities in what is now iraq illustrate how the materials were fashioned and drilled so that they could be worn. in later periods found objects were augmented by beads fabricated from ceramic and glass. coloured beads with varying degrees of shaping have continued to be a significant jewellery item over the centuries. with technological advances metals began to be used extensively. gold was particularly prized for its colour, immutability and the relative ease with which it could be worked. highly sophisticated gold jewellery has been excavated from sumerian tombs dating from 2500 bc in ancient iraq. this jewellery also incorporates coloured gemstones such as lapis lazuli, garnet, turquoise and cornelian, which were fashioned into both simple and complex shapes as shown in figure 1. for example from 3000 bc turquoise beads were combined with garnets and gold. typically beads were fashioned into biconical shapes but there are also examples of more elaborate gem cutting from ur where gemstones were cut and polished to set as inlay into metal brooches (tait, 2006) the gemstones were mostly opaque and surely prized for their intense colours. the ancient egyptians used turquoise, lapis and coral to produce vibrant multi-coloured jewellery and also created beads with similar appearance from glazed composition and faience, figure 2. as glass became more available in the egyptian new kingdom (ca 1567-1085 bc) it was used to imitate natural stones as well as in fine inlay, which could be argued as the precursor to true enamel. jack ogden (ogden, 1982) gives a good overview of ancient sources of metals and gemstones and how they were worked. 3. greek and roman jewellery gold working spread around the eastern mediterranean and examples of fine gold work are known from crete, mycenae and etruria. the emphasis in this work was in the many sophisticated techniques that were used to embellish the gold surfaces. gemstones are relatively rare but examples of an early type of dark blue enamel have been found in mycenean tombs in cyprus dating from the thirteenth century bc (tait, 2006). greek jewellery, drawing on this legacy of fine workmanship, is characterised by the use of gold. only in the hellenistic period (from 325 bc) is there an increased use of coloured gemstones with fine quality cabochon cut garnets and transparent gems such as amethyst and emerald (higgins, 2006). the roman conquest of the hellenistic world and establishment of the empire (27 bc) resulted in jewellery in a similar style with the accent on gold work. but this developed into a much more polychrome style. the romans had a particular fondness for emeralds (in crystal form), sapphires and pearls as shown in figure 3. mummy portraits show how these items were worn. almost all the forms of jewellery that are worn in the twenty-first century had their origin in the roman period. romano-british jewellery reflects a merging of the ‘standard’ roman jewellery with the added influence from the strong celtic metalworking traditions. in particular colour was incorporated 55 cultura e scienza del colore color culture and science | 08 | 2017 | 53 58 an overview of the history of the use of colour in jewellery issn 2384-9568 not only from the example of roman gemstone use but also from the celtic technique of enamelling on bronze, figure 4. 4. anglo-saxon and byzantine jewellery the colour palette changed over the centuries and between different cultures. as shown in figure 5, the anglo-saxons produced amazing jewellery featuring red garnets and blue enamel (care evans, 1989). the technique of inlaying thin slices of garnet into cells of gold, backed with textured gold foils, is thought to have its origins in southern russia around 300 ad and to have spread with migration of the gothic tribes throughout western and northern europe (kidd & webster, 2006). these jewels show a great sophistication in gem cutting and gold working. in northern europe during the ninth and tenth centuries there is an increasing use of silver but in the eastern mediterranean the rise of a particular byzantine style of highly coloured jewels featured gold cloisonné enamelled work, figure 6. 5. medieval jewellery in the early thirteenth century gold was used to set polished gemstones of different colours in simple brooch forms, which also had a practical purpose. subsequently goldsmiths demonstrated their skill by creating intricate high-relief gold work which was covered in enamel and enhanced with gemstones. these highly decorative jewels were particularly figure 1 carved lapis and gold beads from ur, 2500 bc. figure 2 collar of glazed composition beads from egypt, 2020 bc. figure 3 gold bracelet with emeralds and pearls from roman egypt, 1st century ad. figure 4 copper alloy brooch with red and blue enamel faversham,uk, 1st-2nd century ad. figure 5 gold shoulder clasp with garnet inlay and blue enamel sutton hoo treasure england 7th century ad. figure 6 gold reliquary cross with cloisonne enamel constantinople, 11th century ad. all images in figs 1-7 courtesy of the british museum, london (1) (6) (3) (5) (2) (3) 56 cultura e scienza del colore color culture and science | 08 | 2017 | 53 58 bartlett l. issn 2384-9568 doi: 10.23738/ccsj.i82017.05 important as hat badges worn by men, figure 7. such magnificent mediaeval jewels were mostly royal status symbols, indications of piety or princely gifts (somers, 1980). the allegorical scenes depicted in the chased and engraved gold were embellished with rubies, emeralds, sapphires and diamonds and with fine enamels. even pendants that incorporated imitation (7) (12) (9) (11) (8) (10) figure 7 enamelled gold hat badge with rubies and diamonds spain or italy 1526-75. figure 8 enamelled gold pendant with baroque pearl, pearl drop and emerald europe late 16th century. figure 9 brooch with diamonds set in silver and hessonite garnets set in gold europe ca 1700. figure 10 base metal earrings with blue creeper bird heads england 1872. figure 11 anodised and dyed aluminium earrings jane adam ca 1995. figure 12 heat-coloured titanium neckpiece lynne bartlett 2013. all images in figs 8-10 courtesy of the v&a museum, london 57 cultura e scienza del colore color culture and science | 08 | 2017 | 53 58 an overview of the history of the use of colour in jewellery issn 2384-9568 gemstones are finely enamelled on the reverse. unusual materials and large gems were particular prized and baroque pearls (philips, 2000) were often used as the bodies of animals figure 8. in the early fourteenth century gem cutting became more elaborate and faceted stones started to be used extensively. there are examples of other styles of gem cutting such as amethyst and agate cameos. much more information from the fifteenth century onwards can be gleaned from the portraits of the period. many artists were also jewellery designers and faithfully represented the jewels worn by their sitters. in london we have a fine collection of jewellery from the late sixteenth and early seventeenth centuries in the cheapside hoard (forsyth, 2013). the hoard includes many finished pieces incorporating enamelled gold chains set with sapphires, emeralds, garnets and diamonds, carved amethysts and emerald earrings and gold rings set with rubies and other gemstones. it also contains many unset gemstones with a particularly large number of cabochon garnets. the range of materials used shows how extensive the trade in coloured gems had become and indicates the popularity of multicoloured jewellery in the period. 6. eighteenth and nineteenth century by the eighteenth century new sources of gemstones, particularly diamonds, emeralds and topazes from s america, were extensively used as in figure 9. the increased availability and hence reduced price of these gemstones made jewellery more affordable, especially for the growing affluent middle class, and designs and materials became much more subject to changes in fashion. over the ensuing decades fashionable jewellery veered from almost monochrome, diamond-set designs to multicoloured, multi-gemstone pieces and this cycling of styles has continued through the twentieth century. the victorians used an amazing array of gemstones, enamels and other materials, with rare and unusual species particularly prized figure 10. in the late nineteenth century new metals such as platinum and aluminium were increasingly used but both were essentially white metals. the strength of platinum made it an ideal material for ‘invisible’ settings in which the gemstones played the major role in the design of the piece. initially the whiteness of the metal and its relative lack of tarnish meant that it was used as a setting for diamonds replacing the mixed gold and silver settings of early diamond-set jewels but designers at the prestige fine jewellery houses such as cartier increasingly used multi coloured gemstones. aluminium, when it was first produced in the mid-nineteenth century, was treated as a novel material set in gold mounts. the isolation of the pure metal was very difficult and small ingots of the purified metal were shown at the paris exposition in 1855. it is perhaps not surprising that the modernising nephew of napoleon bonaparte, napoleon iii, ordered the fabrication of aluminium utensils and is reported to have eaten from an aluminium plate in preference to a gold one (venetski, 1969). other special uses for aluminium included the cap on the top of the washington monument which was cast from aluminium in 1884 because of its whiteness and resistance to tarnish (dix, 1934). the statue of eros at piccadilly circus was cast in aluminium in 1893. as new processes for aluminium production were developed, the metal became readily available and was used for general construction and the growing aeronautical industry in the twentieth century. 7. twentieth century metals that could be coloured were introduced in the twentieth century. in 1923 anodising of aluminium was developed to provide protection from corrosion of seaplane parts. the process thickened the natural aluminium oxide layer on the surface to provide a durable hard layer. when first created the thin porous oxide layer on the surface of the metal is very receptive to dyes and a wide range of patterning techniques can be used to produce what is effectively a coloured metal surface. dyed anodised aluminium jewellery was probably first produced in the usa but of particular note is the work of the uk jeweller, jane adam an example of which is shown in figure 11. colours may be bright or subtle and, as the pigments are fixed in the thin adherent oxide layer on the surface of the metal, they are very durable. the lightweight of aluminium and the broad range of decorative possibilities have made it a significant material for the twentieth century jeweller. an area of colour that has not been covered so far is patination. examples exist from antiquity of metal sculptures that have been coloured in this way and historic armour used ‘bluing’ to provide multicoloured surface decoration (tellez, 2011). however, as much historic jewellery has been buried, it is often not possible, even if the underlying metal has survived, to be sure if the whole surface was coloured. the twentieth century saw the introduction of a new metal, titanium, whose colour could be said to be produced by a form of patination, i.e. 58 cultura e scienza del colore color culture and science | 08 | 2017 | 53 58 bartlett l. issn 2384-9568 doi: 10.23738/ccsj.i82017.05 oxidation. industry values titanium for its unique combination of high strength and low weight, and although this has been exploited by a few designer/makers, it is titanium’s colour potential that most attracted jewellers to the material and led to its expanding usage through the 1970s and 1980s. the thin oxide layer produced on the surface of the metal by heat or anodising resulted in a wide range of interference colours. various ways of preventing oxygen reaching the surface by masking were used to produce stunning optical effects. research has established (bartlett, 2009) that the use of titanium for designed jewellery was a technical innovation, pioneered in the uk and instigated by the titanium metal producers. early users of titanium tended to use coloured pieces in a similar way to gemstones by setting them in silver frames or fixing them with silver pins. however the strength of titanium meant that very thin sections could be cut as integral pins. its biocompatibility also meant that integral ear wires could be produced without the problems that have been associated with the use of nonprecious metals for such a purpose. one of the pioneer jewellers who first used titanium at birmingham (1965-1968) was ann marie shillito. the first identifiable piece of designed titanium jewellery is a belt buckle. another artist of note in the early decorative use of titanium was pietro pedeferri, a university researcher in electrochemistry in milan, he was inspired by the colour possibilities of the metal to produce wonderful compositions on titanium. in this case he used flat sheets of titanium as a canvas. by the early 1970s titanium had become a regular product used in jewellery courses. however its popularity peaked in the late 1980s and it is only in recent years that its use has been revived, figure 12. 8. conclusion this rapid survey has provided an outline of various materials and methods that have been used to incorporate colour into jewellery over many centuries. jewellers have been shown to readily incorporate new materials and exploit new sources of valued gemstones as they become available while building on the legacy from previous periods. precious metals and gemstones continue to provide the most desired raw materials for the manufacture of jewellery but whatever the material, colour continues to be a major factor in jewellery design and new coloured materials are eagerly adopted. funding this research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. conflict of interest the authors declare that there is no conflict of interest. bibliography bartlett, l, (2009) ‘variability in coloured titanium surfaces for jewellery’, phd thesis, central saint martin’s college of art and design, university of the arts london, london. care evans, a. (1989) ‘the sutton hoo ship burial’, british museum publications, london. dix, jr. e.h. (1934) ‘aluminum cap piece on washington monument’ metal progress (cleveland, oh: american society for metals, december). forsyth, h., (2013) ‘london’s lost jewels’, philips wilson publishers, london. higgins, r. (2006) ‘the greek and roman world, 7000 years of jewellery’, british museum press, london, p.84. kidd, d, & webster, l, (2006) ‘7000 years of jewellery’, british museum press, london, p.101. ogden, j. (1982) ‘jewellery of the ancient world’,trefoil books ltd., london. phillips, c (1996). ‘jewelry from antiquity to the present’, thames and hudson ltd., london, philips, c. (2000) ‘jewels and jewellery’, v&a publications, london. somers cocks, a g, (1980) ‘princely magnificence court jewels of the renaissance, 1500-1630’, debrett’s peerage ltd., london. tellez, h et al (2011), ‘multi-analytical study of patination methods on steel substrates: a full insight into surface chemistry and morphology’, anal bioanal chem, doi 10, 1007/s00216-011-5473-6, oct. 2011. tait, h. (2006) ed. ‘7000 years of jewellery’, british museum press, london. venetski, s. (1969). “”silver” from clay”. metallurgist. 13 (7): 451–453. (7) cultura e scienza del colore color culture and science 23 cultura e scienza del colore color culture and science | 06 | 2016 issn 2384-9568 1antonella versaci antonella.versaci@unikore.it 2alessio cardaci alessio.cardaci@unibg.it 1faculty of engineering and architecture, university of enna “kore” 2department of engineering, university of bergamo the restoration of color in the french historic cities: approaches, methods and experiences abstract in the years following the second world war, the french historical centers appeared marked by the absence of colors as well as by a globally sad image. however, with the onset of the cultural heritage safeguarding policies at urban scale developed since the ‘60s, this trend has been progressively subverted. today, the color is considered as a necessary condition for the understanding and characterization of urban spaces and to improve the people’s quality of life. for these reasons it is therefore subject to special care. inside protected areas – abords de monuments historiques, secteurs sauvegardés, zones de protection du patrimoine architectural, urbain et paysager e/o aires de valorization de l’architecture et du patrimoine specific devices govern the use of the colors. nevertheless, such requirements or “color plans” have given conflicting results. if in several cases, they have determined a kind of homologation many historic centers look similar to each other due to colors considered “pleasant” but not necessarily forming part of the historical tradition and of the urban and architectural lexicon of those places -, in other occasions, better reasoned interventions ruled by architects, urban planners or associations more sensitive to the preservation of color heritage, have given surprising outcomes. from the “opération couleur” carried out in the villages of the ain department to the restoration programs of the nice facades made by bruno goyeneche and the diagonal association, numerous are the examples of interesting safeguarding of the colors of towns and regions of france that this essay intends to analyze. the objective is to highlight peculiarities, strengths, limits and shortcomings of a regulation which seems globally confirm the hypothesis of an effectivity, closely tied to the quality of its actuators. keywords france, historical centers, secteurs sauvegardés, zones de protection du patrimoine architectural, color plans. citation: versaci a. and cardaci a. (2016) ‘the restoration of color in the french historic cities: approaches, methods and experiences’, cultura e scienza del colore color culture and science journal, 06, pp. 23-36, doi:10.23738/ccsj.i62016.02 received 5 february 2016; revised 21 june 2016; accepted 28 september 2016 antonella versaci: fixed terms researcher/ assistant professor in restoration (icar/19) and head of the laboratory of restoration of architectural and cultural heritage at the faculty of engineering and architecture, university kore of enna. she is also associates researcher at ipraus, université de paris-belleville. her research interests focus on the issues of protection, conservation and recovery of historical and architectural heritage. alessio cardaci: assistant professor of drawing and architectural survey (icar/17) and head of the laboratory sabe (survey & analysis of buildings and environment) at the university of bergamo, department of engineering. his research interests are related to the topics of survey, 3d modeling and representation of architecture and cultural heritage. italian translation provided: ‘il restauro del colore delle città storiche francesi: approcci, metodi ed esperienze’ 24 cultura e scienza del colore color culture and science | 06 | 2016 | 23 36 versaci a. and cardaci a. issn 2384-9568 doi:10.23738/ccsj.i62016.02 1. introduction in the years after world war ii, the french historical centers were characterized by the absence of color, faded colors and a globally ‘sad’ image. after the war, in the period of great economic prosperity called the trente glorieuses, the colorfulness will be, in fact, reserved exclusively to the social housing concentrated in the grands ensembles, almost in an attempt to revive an architecture which tends to be monotonous, dominated by the standardization of the components and the prefabrication of the elements (figure 1). with the abandonment of the rénovation urbaine policies and the simultaneous beginning of reflections made at an international level about the problem of color and street furniture in the historic centers, france too began to consider the question of the restauration du patrimoine coloré. while in italy giovanni brino elaborates an innovative the city of color plan for the city of turin (1978), aimed at the reintroduction of the original color by means of restoration works of the facades based on archival documents and other iconographic and literary sources [1], on the other side of the alps jean-philippe lenclos introduces the concept of ‘color geography’, according to which each country, region, city and / or village expresses its own colors (figure 2). in fact, every place has its own unique, traditional ‘color vocabulary’: a knowledge element indispensable for an urban development respectful of the local figure 1 dossier on the grands ensembles published in 1953 on issue no. 46 of architecture d’aujourd’hui magazine. figura 1 dossier sui grands ensembles pubblicato nel 1953 sul n. 46 della rivista architecture d’aujourd’hui. 1. introduzione negli anni successivi al secondo conflitto mondiale, i centri storici francesi apparivano contraddistinti dall’assenza di colore, da tinte sbiadite e da un’immagine globalmente ‘triste’. dopo la guerra, nel periodo di grande prosperità economica denominato le trente glorieuses, la policromia sarà in effetti riservata esclusivamente agli alloggi sociali concentrati nei grands ensembles, quasi nel tentativo di ravvivare un’architettura dal carattere tendenzialmente monotono, dominato dalla standardizzazione dei componenti e dalla prefabbricazione degli elementi (figura 1). con l’abbandono delle politiche di rénovation urbaine e parallelamente all’avvio di riflessioni compiute a livello internazionale sul problema del colore e dell’arredo urbano nei centri storici, anche la francia inizia a prendere in considerazione la questione della restauration du patrimoine coloré. mentre in italia giovanni brino elabora un innovativo piano del colore della città di torino (1978) finalizzato alla reintroduzione della colorazione originaria per mezzo di operazioni di restauro delle facciate basate su documenti d’archivio e altre fonti iconografiche e letterarie [1], oltralpe jean-philippe lenclos introduce il concetto di ‘geografia del colore’ secondo il quale ogni paese, regione, città e/o villaggio esprime dei colori propri (figura 2). ogni luogo presenta infatti un suo specifico e tradizionale 25 cultura e scienza del colore color culture and science | 06 | 2016 | 23 36 the restoration of color in the french historic cities: approaches, methods and experiences issn 2384-9568 characters, conscious and sustainable [2]. over time, with the rise of the awareness about the architectural, environmental and landscape heritage of the historic cities, the establishment of policies for the protection of sites and espaces protégés, increasingly ductile and attentive to the evolutionary aspects and the identity of those portions of the territory and characterized by a democratic and participatory vision, the theme of the historical architecture color has achieved increasingly important dimensions, especially in the perception that the citizens have of it (and of its social role). today, the color is therefore regarded as a necessary condition for the understanding, the characterization and the recognition of the urban space and for the improvement of the quality of life of the inhabitants. for these reasons, it is the subject of a certain care and attention, according to the analytical/operating mode, yet limited and regulated, not always adequately assessed and met in the execution phase. in fact, the experiments conducted have yielded conflicting outcomes. in many cases, they led to a certain homologation many ancient centers seem similar because of the colorings, considered pleasing but not necessarily forming part of the historical tradition and of the architectural and urban vocabulary of those places – but on other occasions, better planned interventions, ruled by technicians or associations more attentive to the safeguard of the color heritage, have had much more consistent results. from the opération couleur of the villages of the ain department to the restoration programs of the facades of nice and marseille, there are many examples of recovery of the typical shades in towns and regions of france; this essay aims to trace them. the goal is to highlight the characteristics, strengths, limitations and shortcomings of an experiment that seems to globally confirm the hypothesis of an effectiveness tightly bound to figure 2 the studies of jeanphilippe and dominique lenclos, looking for chromatic peculiarities in terms of geography, history and traditions of the places, follow an original approach that made history worldwide figura 2 gli studi di jean-philippe e dominique lenclos alla ricerca delle particolarità cromatiche in termini geografici, storici e delle tradizioni dei luoghi, seguono un approccio originale che ha fatto scuola a livello mondiale. ‘vocabolario cromatico’: elemento di conoscenza indispensabile per uno sviluppo urbano rispettoso del carattere locale, consapevole e sostenibile [2]. nel corso del tempo, con l’accrescersi della sensibilità nei confronti del patrimonio architettonico, ambientale e paesaggistico delle città storiche, l’instaurarsi di politiche di protezione dei siti e degli espaces protegés sempre più duttili, attente agli aspetti evolutivi e identitari di tali porzioni di territorio e contraddistinte da una visione democratica e partecipativa, il tema del colore dell’architettura storica ha assunto dimensioni sempre più importanti, soprattutto nella percezione che di essa (e del suo ruolo sociale) hanno i cittadini. oggi, il colore è dunque considerato quale condizione necessaria per la comprensione, la caratterizzazione e la riconoscibilità dello spazio urbano e il miglioramento della qualità di vita degli abitanti. per tali ragioni, è oggetto di una certa cura e attenzione, secondo modalità analitico/operative tuttavia limitatamente regolamentate, non sempre sufficientemente vagliate e rispettate in fase esecutiva. di fatto, le esperienze condotte hanno dato risultati contrastanti. se in parecchi casi, hanno determinato una certa omologazione molti antichi centri sembrano simili grazie a coloriture ritenute gradevoli ma non necessariamente facenti parti della tradizione storica e del vocabolario architettonico e urbano di quei luoghi -in altre occasioni, interventi meglio ragionati, governati da tecnici o associazioni più sensibili alla salvaguardia del patrimonio cromatico, hanno avuto esiti molto più coerenti. dalle opération couleur dei villaggi del dipartimento dell’ain ai programmi di restauro delle facciate di nizza e marsiglia, numerosi sono gli esempi di recupero delle tonalità caratteristiche di cittadine e regioni della francia, che questo saggio si propone di ripercorrere. l’obiettivo è quello di mettere in evidenza le peculiarità, i 26 cultura e scienza del colore color culture and science | 06 | 2016 | 23 36 versaci a. and cardaci a. issn 2384-9568 doi:10.23738/ccsj.i62016.02 the quality of its actuators. 2. color restoration between perception and chromatic identity a pioneer in the field of restoration of the chromatic heritage of the historical centers is the work accomplished by jean-philippe lenclos, the first french designercolorist. since the late 60s, after an inspiring journey to japan, he developed a systematic methodology, funded by the french government, aimed at compiling an actual color atlas related to every region of the nation. next to the objective study of minerals, soil, paints and building materials, he put the attention on some subjective aspects related to the changes in color depending on the light, air, humidity of rain, drought, etc. [3]. this concept starts from the idea that a building may reflect the same set of colors of its physical surroundings, yet its color is never static but, on the contrary, in continuous evolution. gradually perfected over time, the procedure proposed by lenclos is based on simple yet precise gestures and is divided into three phases. the first concerns the survey of samples of ‘permanent’ colors (that is, related to the materials belonging to the constructed landscape) and of color components objectively not detectable and changing (such as the sky, localized shadows, vegetation) belonging to the natural environment, as well as the set of signs that refer to the societies that produce them and the way in which cultures and communities express them. from the sampled material will be identified later, with colored pencils or watercolors, the colors that make up the whole result. the second stage consists in the cataloguing figure 3 files of plans drawn up by the atelier 3d couleur for the vieux nîmes and the secteur sauvegardé of salers (http://www.atelier3dcouleur. c o m / f r / a r c h i t e c t u r e / p a t r i m o i n e secteurs-proteges). figura 3 schede di sintesi di progetti elaborati dall’atelier 3d couleur per il vieux nîmes e il secteur sauvegardé di salers (http://www.atelier3dcouleur. c o m / f r / a r c h i t e c t u r e / p a t r i m o i n e secteurs-proteges) pregi, i limiti e le carenze di una sperimentazione che sembra globalmente confermare l’ipotesi di una efficacia strettamente vincolata alle qualità dei suoi attuatori. 2. il restauro del colore tra percezione e identità cromatica pioniera in materia di restauro del patrimonio cromatico dei centri storici, è l’opera compiuta da jean-philippe lenclos, il primo designercolorista francese. sin dalla fine degli anni ’60, in seguito a un viaggio ispiratore compiuto in giappone, egli ha messo a punto una metodologia sistematica, finanziata dal governo francese, finalizzata alla compilazione di un vero e proprio atlante cromatico relativo a ogni regione della nazione. accanto allo studio obiettivo dei minerali, del suolo, delle pitture e dei materiali per l’edilizia utilizzati, egli ha posto l’attenzione anche su alcuni aspetti soggettivi legati al variare dei colori in funzione della luce, dell’aria, dell’umidità della pioggia, della siccità, ecc. [3]. la sua riflessione prende le mosse dall’idea che per quanto un edificio possa riflettere lo stesso insieme di colori del suo intorno fisico, il suo colore non è mai statico ma, al contrario, in continua evoluzione. via via perfezionata nel corso del tempo, la procedura proposta da lenclos si fonda su gesti semplici benché precisi e si struttura in tre fasi. la prima riguarda la ricognizione di campioni di colori ‘permanenti’ (cioè riferibili a materiali appartenenti al paesaggio costruito) e delle componenti cromatiche non obiettivamente rilevabili e mutevoli (quali il cielo, le ombre localizzate, la vegetazione) appartenenti all’ambiente naturale, nonché di quell’insieme di segni che si rifanno alle trame delle società 27 cultura e scienza del colore color culture and science | 06 | 2016 | 23 36 the restoration of color in the french historic cities: approaches, methods and experiences issn 2384-9568 and classification of the information collected through the ncs color system natural colour system®© and later in developing a repertoire of colors (planches de synthèse). the latter is divided into a general palette, from the most delicate shades, constituted by the colors destined to the surfaces of greater extension (walls, roofs, horizontal surfaces) and in a color points palette, from the most intense shades, to be used for the finishes (doors, windows, shutters, wainscots) (figure 3). the studies performed by lenclos with his wife dominique have resulted in numerous publications in france and abroad [4,5,6]. more than just manuals, these are real testimonies of cultures and traditions, structural and formal characterizations, threatened by an increasingly standardized engineering practice which occurs with the use of artificial production materials, often cheaper but with no real relationship with the socio-cultural and environmental context. this methodological approach has highlighted the importance of proceeding to a knowledge of the area centered on the objective observation of the color phenomena and on the use of perception. the latter is seen in multi-sensorial, environmental and material terms, as a tool to grasp the relationship with memory and history, architecture and color, extremely strong in the past and of creative value. on this track, jacques fillacier devotes many years of study to psychometrics, focusing on the link between physical measurements of the color element and the human perception of color. through psychometrics, it is possible to identify the harmony composed by perceptually equidistant colors, yet able to elicit different feelings in human beings: “the union of the various colors on a surface presents a number of more or less considerable combinations. the choice of these colors and their arrangement can result in more or less conscious psychological reactions in the viewer, ranging from pleasure to aversion (sensory level), from clarity to incoherence (mental level). the color is at the same time ‘show’ and ‘speech’, rarely only one or the other “[7]. color is given an important social function; it therefore becomes an essential element for the creation of a calm and balanced living environment [8]. with the contribution of andré and monique lemonnier, georges patrix and bernard lassus, the idea of a new profession at the crossroads between architecture and design of the products is proposed: the colorisme-conseil [9]. these color consultants perform their first experiments on industrial che li producono e al modo in cui le culture e le comunità le esprimono. dal materiale prelevato si individueranno in seguito, con matite colorate o acquarelli, le tinte che compongono l’insieme cromatico. la seconda fase consiste nella catalogazione e classificazione delle informazioni raccolte tramite il sistema cromatico ncs natural colour system®© e successivamente nell’elaborazione di un repertorio dei colori (planches de synthèse). quest’ultimo si suddivide in una tavolozza generale, dalle tonalità più tenui, costituita dai colori destinati alle superfici di maggiore estensione (muri, tetti, superfici orizzontali) e in una tavolozza dei punti di colore, dalle tonalità più intense, da utilizzare per le finiture (porte, finestre, imposte, zoccolature) (figura 3). le campagne di studio portate avanti da lenclos insieme alla moglie dominique hanno dato luogo a numerose pubblicazioni in francia e a livello internazionale [4,5,6]. più che semplici manuali, queste rappresentano delle vere e proprie testimonianze su culture e tradizioni, caratterizzazioni strutturali e formali, minacciate da una prassi costruttiva sempre più standardizzata e omologata, che ricorre all’utilizzo di materiali di produzione artificiale, spesso più economici benché privi di un reale rapporto con il contesto socio-culturale e ambientale. tale approccio metodologico ha messo in risalto l’importanza di procedere a una conoscenza dei luoghi imperniata sull’osservazione oggettiva dei fenomeni cromatici e sull’uso della percezione. quest’ultima è vista in chiave multisensoriale, ambientale e materica, come strumento atto a cogliere quel legame con memoria e storia, architettura e colore, estremamente forte in passato e dalla valenza creatrice. su questa scia, jacques fillacier dedica numerosi anni di studio alla psicometria, soffermandosi sul legame tra le misure fisiche dell’elemento cromatico e la percezione umana del colore. e’ proprio mediante la psicometria che è possibile identificare armonie composte da colori percettivamente equidistanti ma capaci di suscitare nell’uomo sentimenti diversi: “l’assemblaggio dei vari colori su una superficie presenta un numero di combinazioni più o meno considerevole. la scelta di questi colori e la loro disposizione può determinare nello spettatore reazioni psicologiche più o meno consapevoli che vanno dal piacere all’avversione (livello sensoriale), dalla lucidità all’incoerenza (livello mentale). il colore è al contempo ‘spettacolo’ e ‘discorso’, raramente solo uno o l’altro” [7]. al colore viene assegnata un’importante funzione sociale; esso diviene pertanto un 28 cultura e scienza del colore color culture and science | 06 | 2016 | 23 36 versaci a. and cardaci a. issn 2384-9568 doi:10.23738/ccsj.i62016.02 sites, where the introduction of chromaticism becomes a tool for both improving the quality of life of workers, and for the construction of an identity of the production sites. at the same time, they develop their own indexing system of colors and conceive some nuancier for the paints manufacturers. france and michel cler specialize in the production of études cromo-paysagères; chromium-études paysagères: studies devoted to the definition of both local micro-projects on residential sites and urbanization projects on a large scale in which it is necessary to take into account the relationship with the natural habitat [10]. their work is expressed through the concept of chromatic environments for urban spaces. essential aspects of these color studies later defined chromatictownscape carried out with the help of the natural colour system®©, are the analysis of the sites’ spatial and specific characteristics, the evaluation of mineral and vegetal elements and the determination of light quality, a synthesis of all the colors found and, finally, any relevant information for the understanding of the architecture and of the local culture [11, 12]. initially used for the new urbanizations (lille-est, 1969; saint-quentinen-yvelines, 1975; cergy-pontoise e marne-lavallée, 1977; melun-sénart, 1981), these plans have had a major impact on other types of urban and architectural situations, such as ancient towns and rural villages, because of their focus on the improvement of environmental quality and, therefore, certainly connected with the need for protection of the constructed landscape and the development of the architectural and historical heritage (figure 4) [13]. 3. the color of the urban fronts: regulatory requirements and application outcomes since the late 80’s the spread of polychrome in french cities was taking place: the most spectacular in both the number of colored facades and in terms of chromatic power are found in the alsatian towns but the phenomenon is present in almost all the regions of the country [14]. these are mostly isolated cases, yet increasingly they are the result of true campaigns held by the local administrations in order to give coherence, rehabilitate or even renew the image of the city and in particular the coeur of towns and villages through the color. these activities were in general motivated by a clear desire for ‘beautification’ by the administrations and supported by the idea to resume ties with tradition through the rediscovery / re-proposal of the nuances of the past; however, the results were often disappointing. from a regulatory point of view, according elemento essenziale per la costituzione di un ambiente di vita sereno ed equilibrato [8]. con il contributo di andré e monique lemonnier, georges patrix e bernard lassus viene portata avanti l’idea di una nuova professione situata al crocevia tra l’architettura e il design dei prodotti: il colorisme-conseil [9]. questi consulenti del colore compiono le prime sperimentazioni sui siti industriali, dove l’introduzione del cromatismo diventa sia uno strumento per il miglioramento della qualità della vita dei lavoratori, sia di costruzione dell’identità dei luoghi della produzione. contemporaneamente, essi sviluppano un proprio sistema di indicizzazione dei colori e concepiscono dei nuancier per le case produttrici di pitture. michel e france cler si specializzano nella realizzazione di études cromo-paysagères; studi votati tanto alla definizione di progetti locali su micro siti residenziali quanto a progetti di urbanizzazione su larga scala in cui è necessario tenere conto della relazione con l’habitat naturale [10]. il loro lavoro si esprime attraverso la concezione di ambienti cromatici per gli spazi urbani. aspetti essenziali di tali studi del colore più tardi definiti chromatictownscape effettuati con l’ausilio del natural colour system®©, sono l’analisi delle caratteristiche spaziali e specifiche dei siti, la valutazione degli elementi minerali e vegetali presenti nonché la determinazione della qualità della luce, una sintesi di tutti i colori ritrovati e, infine, ogni elemento utile alla comprensione dell’architettura e della cultura locale [11, 12]. inizialmente utilizzati per le nuove urbanizzazioni (lille-est, 1969; saint-quentinen-yvelines, 1975; cergy-pontoise e marne-lavallée, 1977; melun-sénart, 1981), questi piani hanno avuto un impatto importante anche su altri tipi di realtà urbanistiche e architettoniche, ad esempio centri antichi e villaggi rurali, poiché finalizzati al miglioramento della qualità ambientale e, pertanto, certamente connessi con le necessità di tutela del paesaggio costruito e di valorizzazione del patrimonio architettonico e storico (figure 4) [13]. 3. il colore dei fronti urbani: presupposti regolamentari e esiti applicativi dalla fine degli anni ’80 si assiste al dilagare della policromia nelle città francesi: gli effetti più spettacolari sia nel numero di facciate colorate che in termini di potenza cromatica si riscontrano nelle città alsaziane ma il fenomeno si ripete quasi in tutte le regioni del paese [14]. si tratta di casi per lo più isolati ma sempre più frequentemente, è il risultato di vere e proprie campagne indette dalle amministrazioni locali al fine di ridare coerenza, riabilitare o ancora rinnovare l’immagine delle città e in particolare 29 cultura e scienza del colore color culture and science | 06 | 2016 | 23 36 the restoration of color in the french historic cities: approaches, methods and experiences issn 2384-9568 to the local plan d’urbanisme (plu) the local planning tool every rebuilding or modification of facades needs for a déclaration de travaux (art. l422-2 of the code de l’urbanisme). in contrast, within the protected zones abords de monuments historiques, secteurs favorites had, zones de protection du patrimoine architecturale, urbain et paysager (zzpaup) and / or the more recent aires de mise en valeur de l’architecture et du patrimoine (avap) -, specific devices and the clearance by the architect of french buildings (abf), govern the use of colors as well as of the materials and the finishes of the facades, of the frames and of all the other external architectural elements (e.g. shops signs, etc.). often, the development of a ‘color map’ by an architecte-conseil chosen by the municipality in order to maintain the global harmony of the sites and avoid aesthetic disorders is accompanied by such urban planning / heritage instruments, completing the figure 4 france and michel cler, color reference chart of the romaniquette of istres, 1985 (© fonds national d’art contemporain, centre pompidou, paris) figura 4 france e michel cler, schema di riferimento cromatico dell’area della romaniquette a istres, 1985 (©fonds national d’art contemporain, centre pompidou, parigi) del coeur di paesi e villaggi, tramite il colore. attività in generale motivate da una chiara volontà di ‘abbellimento’ da parte delle amministrazioni e supportate dall’idea di riannodare i legami con la tradizione, attraverso la riscoperta/riproposta delle sfumature appartenenti al passato, ma dagli esiti spesso deludenti. dal punto di vista regolamentare, secondo il plan local d’urbanisme (plu) lo strumento di pianificazione a scala locale ogni rifacimento o modifica delle facciate necessità di una déclaration de travaux (art. l422-2 del code de l’urbanisme). diversamente, all’interno delle zone protette – abords de monuments historiques, secteurs sauvegardés, zones de protection du patrimoine architecturale, urbain et paysager (zzpaup) e/o le più recenti aires de mise en valeur de l’architecture et du patrimoine (avap) –, specifici dispositivi nonché il nulla osta dell’architetto degli edifici di francia (abf), regolano l’utilizzo dei colori oltre che i materiali e le finiture delle facciate, degli infissi 30 cultura e scienza del colore color culture and science | 06 | 2016 | 23 36 versaci a. and cardaci a. issn 2384-9568 doi:10.23738/ccsj.i62016.02 requirements (figure 5). as part of an increasing number of initiatives, more and more engaging, developed at a municipal or inter-communal level, almost in some kind of competition, specific financial incentives are made available to the citizens to proceed with the renovation of the facades and so to regain the splendor of the past: opérations façades, réaménagement haut en couleur, combattre la grisaille are just some of the slogans that promote such programs (figure 6). the accompanying actions that the atelier cler performs in the department of ain [15] since 1977, on the mandate of the conseil d’architecture, d’urbanisme et de l’environnement (caue), are highly participatory and with media impact. the elaboration of color cards, in this case, concerns not a city but a large geographical area. a ground-breaking job by the atelier cler, in concert with the abf, which followed a large number of communities and institutions engaged in the search for their distinctive and characterizing points, detecting the chromatic atmosphere of their towns and providing useful elements for the construction of a global harmonization, not bound by preestablished and permanent codes but, on the contrary, in constant evolution (figure 7 8). the activity carried out in the provence-alpescôte-d’azur region by bruno goyeneche and by the diagonal association is equally substantial. the urban renewal operation, launched in 1975 in the historic center of nice under the programme d’aménagement du territoire concerte urbain (pact) is a model for other cities which, from that experience, launched their own global figure 5 example of charte de couleur attached to the plu of the city of puteaux figura 5 esempio di charte de couleur allegata al plu della città di puteaux figure 6 some posters related to the couleur/façades operations figura 6 alcune locandine relative a operazioni couleur/façades e di tutti gli altri elementi architettonici esterni (ad esempio le insegne delle botteghe, ecc.). sovente, l’elaborazione di una ‘carta cromatica’ da parte di un architecte-conseil scelto dal comune al fine di mantenere l’armonia globale dei siti ed evitare disordini estetici si accompagna a tali strumenti urbanistico/patrimoniali, completando le prescrizioni in materia (figura 5). nell’ambito di iniziative sempre più numerose ed accattivanti sviluppate a livello comunale o inter-comunale, quasi in una sorta di competizione, sono inoltre messi a disposizione dei cittadini degli specifici incentivi economici per procedere al rifacimento delle facciate e ritrovare così lo splendore del passato: opérations façades, réaménagement haut en couleur, combattre la grisaille, sono solo alcuni degli slogan che promuovono tali programmi (figura 6). di grande impatto partecipativo e mediatico, sono le azioni di accompagnamento che sin dal 1977, l’atelier cler svolge nel dipartimento dell’ain [15], su mandato del relativo conseil d’architecture, d’urbanisme et de l’environnement (caue). l’elaborazione di carte cromatiche riguarda nel caso specifico non una città ma un’area geografica vasta. un lavoro precursore con il quale l’atelier cler, in accordo con l’abf, ha seguito un elevato numero di collettività ed istituzioni impegnate nella ricerca dei propri tratti distintivi e caratterizzanti, rilevando l’atmosfera cromatica dei loro centri abitati e fornendo elementi utili alla costruzione di un’armonizzazione globale, non vincolata da codici precostituiti e permanenti ma, al contrario, in costante evoluzione (fig. 7 e 8). altrettanto corposa è l’attività svolta nella regione provence-alpes-côte-d’azur da bruno goyeneche e dall’associazione diagonal. l’operazione di restauro urbano avviata nel 1975 nel centro storico di nizza nell’ambito del programme d’aménagement concerté du territoire urbain (pact) rappresenta un modello per altre città che, a partire da quell’esperienza, hanno avviato a loro volta processi globali di rivitalizzazione (vence, grasse, menton, gourdon, levens, drap, ecc.) [16]. il metodo di 31 cultura e scienza del colore color culture and science | 06 | 2016 | 23 36 the restoration of color in the french historic cities: approaches, methods and experiences issn 2384-9568 revitalization processes (vence, grasse, menton, gourdon, levens, drap, etc.) [16]. the goyeneche method, based on rigorous research of local history and the use of traditional techniques and materials, is to propose a kind of interpretation grid for the return of the polychrome decoration of the buildings [17]. his work is mainly carried out in three stages. the first is related to the relief of the actual state of the facades and their classification on three levels: satisfactory, mediocre and bad. the second concerns the establishment of a list of architectural rules and the definition of a color sample for each property and for each different element of the prospectus. as for nice, three palettes were defined in relation to the present architectural styles: niçois (xixearly xx century), eclectic of the years 1880 to 1914 (art nouveau) or art déco (1918-1939). nice consists, in fact, if two distinct areas: the old town, polychrome and of italian inspiration, and the new english city, white and of british and russian inspiration. the color plans proposed by the architect define the order of the restoration operations aimed at the protection figure 7 map of the opérations couleur carried out in the ain department by the conseil d’architecture, d’urbanisme et de l’environnement (© caue de l’ain). figura 7 mappa delle opérations couleur realizzate nel dipartimento dell’ain dal conseil d’architecture, d’urbanisme et de l’environnement (©caue de l’ain). goyeneche, basato su rigorose ricerche della storia locale e sull’utilizzo di tecniche e materiali tradizionali, consiste nel proporre una sorta di griglia d’interpretazione per la restituzione della policromia e del decoro degli edifici [17]. il suo lavoro si svolge essenzialmente in tre tappe. la prima è relativa al rilievo dello stato di fatto delle facciate e alla loro classificazione su tre livelli: soddisfacente, mediocre e cattivo. la seconda riguarda la costituzione di un elenco di regole architettoniche e la definizione di un campionario dei colori per ogni immobile e per ogni differente elemento del prospetto. per quanto riguarda nizza, sono state definite tre palettes in relazione agli stili architettonici presenti: niçois (xix-inizio xx secolo), eclettico degli anni 1880-1914 (art nouveau) o art déco (1918-1939). nizza si compone, in effetti, di due zone ben distinte: la città vecchia, policroma e d’ispirazione italiana e la città nuova inglese, bianca e d’ispirazione britannica e russa. i piani del colore proposti dall’architetto definiscono l’ordine secondo il quale dovranno svolgersi le operazioni di restauro finalizzate alla tutela 32 cultura e scienza del colore color culture and science | 06 | 2016 | 23 36 versaci a. and cardaci a. issn 2384-9568 doi:10.23738/ccsj.i62016.02 and enhancement of the color and architectural qualities of the historic buildings. the main goal is to harmonize the various parts of the fronts, while respecting the unity if style. the suggested color ranges also concern the street furniture and all the essential elements of the urban landscape, including the ground. the last stage consists in assisting a number of building sites. finally, the association deals with the storage of the information obtained during the detection phase, the restoration projects, the photographs and graphic simulations relating to the application of the colors on the buildings proposed foe the object of the intervention (figure 9). in marseille instead, giovanni brino, after his heroic experience in turin, realizes a color and materials database, as the municipality consultant from 1987 to 2005. in this case, however, in order to recognize the specific local colors, given the shortage of archival material, the architect uses specific profiling to conduct systematic surveys [18] in urban neighborhoods and coastal villages now part of the city yet differentiated from each other by geography and by the history of the material and of its inhabitants. this path had been dictated by a municipal ordinance of 1990 which brought to light an old provision of the last century, requiring the inhabitants to restore the facades of their buildings every ten years. as a result, the survey was thoroughly performed in order to provide the residents with the information needed for the proper restoration of the façades – which were until then in a state of advanced figure 8 an example of opération couleur in coligny (© caue de l’ain) figura 8 un esempio di opération couleur a coligny (©caue de l’ain). figure 9 two examples of facade restoration in nice made by bruno goyeneche figura 9 due esempi di restauro di facciate a nizza realizzate da bruno goyeneche e valorizzazione delle qualità cromatiche e architettoniche degli edifici storici. l’obiettivo principale è di armonizzare le diverse parti dei fronti, nel rispetto dell’unità di stile. le gamme cromatiche suggerite riguardano, inoltre, anche l’arredo urbano e tutti gli elementi essenziali del paesaggio urbano, tra cui il suolo. l’ultima fase consiste nell’assistenza a un certo numero di cantieri. infine, l’associazione si occupa dell’archiviazione su base informatica delle informazioni acquisite in fase di rilevamento, dei progetti di restauro, di fotografie e di simulazioni grafiche relative all’applicazione delle tinte proposte sui fabbricati oggetto d’intervento (figura 9). a marsiglia invece, giovanni brino, forte dell’eroica esperienza torinese, realizza, in qualità di consulente della municipalità dal 1987-2005, una banca dati dei colori e dei materiali. in questo caso però, al fine di poter riconoscere le specifiche cromie locali, data la forte carenza di materiale d’archivio, l’architetto si serve di schedature specifiche per realizzare rilievi sistematici [18] nei quartieri urbani e i villaggi costieri ormai parte della città, tuttavia tra loro differenziati sia per carattere geografico, sia per la storia dei materiali e dei suoi abitanti. tale percorso era stato dettato da una ordinanza comunale del 1990 che, riportando alla luce una vecchia disposizione del secolo precedente, imponeva agli abitanti di restaurare ogni dieci anni le facciate dei propri palazzi. di conseguenza, l’indagine veniva applicata a tappeto, per poter dotare gli abitanti delle informazioni necessarie per procedere al restauro corretto delle facciate, 33 cultura e scienza del colore color culture and science | 06 | 2016 | 23 36 the restoration of color in the french historic cities: approaches, methods and experiences issn 2384-9568 decay and summarily repainted with acrylic paints that inevitably led to the loss of colors and of the original décor. [19] since 1997, the euroméditerranée project allowed to deepen the experience in the old town districts of marseille (jolette, porte d’aix and belle de mai) and subsequently within the ancient bastides: the vast agricultural properties placed on the hills immediately above the heart of the city. alongside the survey regarding the colors and the materials of the city fronts, a further analysis is developed on the types that characterize the different neighborhoods: the stone facades or with plaster and lime coloring, the faux stone or the bricks, etc. these data were included in a number of publications produced by the atelier du patrimoine de la ville de marseille, but mostly they allowed the experiences of professional training aimed at local artisans, through the organization of façades à l’ancienne internships: schoolsconstruction sites aimed to demonstrate the feasibility of restorations properly carried out using the original materials. other organizations, like terres et couleurs, operate with similar goals: since 2006 it has launched more than 20 operations and 500 construction sites, aimed at benevolently supporting the population of city centers and villages to regain the couleurs locales, using natural paints and, specifically, ochre-based pigments (figure 10). 4. conclusions the analysis of the interventions observed in france shows that the last twenty years witnessed a sort of increasing frenzy toward finding a color consistency as an indicative factor of a specific local identity and tradition. despite the important theoretical contributions retraced above, in general, the practical decisions appear to have been based on the myth of the recovery of alleged specific characters of each city, but they do not always seem the result of extensive and relevant studies on the history, urban morphology and architecture of places. figure 10 activities of the association terres et couleurs in the secteurs sauvegardés of dijon and richelieu figura 10 attività dell’associazione terres et couleurs nei secteurs sauvegardés di dijon e richelieu sino a quel momento in stato di avanzato degrado e ridipinte sommariamente con vernici acriliche che inevitabilmente conducevano alla perdita dei colori e dei decori originali [19]. dal 1997, il progetto euroméditerranée ha permesso di approfondire l’esperienza nei quartieri del centro storico di marsiglia (jolette, porte d’aix e belle de mai) e successivamente in seno alle antiche bastides: le vaste proprietà agricole poste sulle colline immediatamente sovrastanti il cuore della città. accanto all’indagine riguardanti i colori e i materiali dei fronti cittadini, viene sviluppata una ulteriore riflessione sulle tipologie caratterizzanti i vari quartieri: le facciate in pietra o con intonaco e coloritura a calce, quelle in finta pietra o ancora in mattoni a vista, ecc. questi dati sono confluiti in numerose pubblicazioni realizzate dall’atelier du patrimoine de la ville de marseille ma soprattutto hanno permesso delle esperienze di formazione professionale rivolte agli artigiani locali, per mezzo dell’organizzazione di stage de façades à l’ancienne: cantieri-scuola volti a dimostrare la fattibilità di restauri eseguiti impiegando correttamente i materiali originari. con simili obiettivi, operano anche altre associazioni quali terres et couleurs che dal 2006 ha lanciato più di 20 operazioni e 500 cantieri, finalizzate ad aiutare in maniera benevola la popolazione di centri storici e villaggi a ritrovare i couleurs locales, utilizzando pitture naturali e, in particolare, pigmenti a base di ocra (figura 10). 4. conclusioni dall’analisi degli interventi osservati in francia si evidenzia come nell’ultimo ventennio si sia assistito a una sorta di frenesia crescente verso la ricerca di una coerenza cromatica quale elemento indicativo di una specifica identità e tradizione locale. malgrado gli importanti apporti teorici sopra ripercorsi, in generale, le scelte operative sembrano essere state fondate sul mito del recupero di presunti caratteri specifici di ogni città, ma non sempre appaiono il risultato di studi approfonditi e pertinenti sulla storia, la 34 cultura e scienza del colore color culture and science | 06 | 2016 | 23 36 versaci a. and cardaci a. issn 2384-9568 doi:10.23738/ccsj.i62016.02 the result is a flattening of the territorial differences and a preference towards a culture of appearance, that aims to achieve an atmosphere dominated by a pictoresque agréable considered promising in terms of tourism development [20]. without any doubt, many old town centers resemble each other: almost anywhere in france the ocher tints dominate, more or less rosy, independently from the sands and the other local materials. or the provençalflavored polychrome, even where cities had a gray appearance because they were built with the local basalt, like puy-en-velay (figure 11). as for the typical maisons à-colombages, often the wooden beams are exposed even when originally made for the sole structural purpose and not to be left in view – and, moreover, painted in colorful colors, like in troyes (figure 12). these are operations with a sometimes excessive character, dictated more by the desire to promote a suggestive image of the city than to really identify with the urban heritage [21]. besides a few special cases, the issue of colorings in historical centers seems free from concerns related to the theme of restoration and, more than the protection and conservation of certain colors associated with historicized data environments and related historical layers, the main interest seems to be in the planning of new colors to be assigned to the fronts of old buildings and the accompanying constructions. figure 11 on the left the city of puy-en-velay and on the right the city of mulhouse, both characterized by bright polychrome colorings which do not actually belong to the tradition of the place figura 11 a sinistra la città di puy-en-velay e a destra la città di mulhouse entrambe caratterizzate da accese coloriture policrome in realtà non appartenenti alla tradizione del luogo figure 12 on the left, uniform coloring white painted walls and green shutters – of the ile de ré, the result of a deliberate aesthetic choice by the local administration. on the right, maisons à colombages with visible wooden structure, painted in bright colors in the city of troyes, with a typical alsatian taste figura 12 a sinistra la coloritura uniforme – muri dipinti in bianco e persiane in verde dell’ile de ré, frutto di una scelta estetica intenzionale da parte dell’amministrazione locale. a destra, maisons à colombages con la struttura lignea a vista e verniciata a tinte forti nella città di troyes, dal tipico sapore alsaziano. funding this work was supported by the universities of enna kore and bergamo morfologia urbana e l’architettura dei luoghi. ne risulta un appiattimento delle differenze territoriali e una preferenza nei confronti di una cultura delle apparenze che si pone l’obiettivo di raggiungere un’atmosfera dominata da un certo pittoresque agrèable considerato promettente in termini di sviluppo turistico [20]. è indubbio che molti centri storici si somiglino: praticamente ovunque in francia dominano le tinte giallo ocra più o meno rosate e ciò indipendentemente dalle sabbie e dagli altri materiali locali. o ancora le policromie dal sapore provenzale, anche lì dove le città erano nate con un aspetto grigio perché costruite con il basalto locale, come a puy-envelay (figura 11). per quanto riguarda le tipiche maisons à colombages, spesso le intelaiature lignee a traliccio sono messe a nudo anche quando originariamente realizzate ai soli fini strutturali e non per essere lasciate a vista – e in più verniciate in colori variopinti come a troyes (figura 12). si tratta di operazioni dal carattere a volte eccessivo dettate più dalla volontà di promuovere un’immagine suggestiva della città che di identificarsi davvero nel suo patrimonio urbano [21]. al di là di alcuni casi particolari, il tema delle coloriture nei centri storici sembra svincolato dalle altre preoccupazioni inerenti la tematica del restauro e più che alla tutela e alla conservazione di determinate tinte legate a dati ambienti storicizzati e alle connesse stratificazioni storiche, sembra predominare l’interesse verso la pianificazione di nuove cromie da attribuire ai fronti degli antichi edifici e all’edilizia di accompagnamento. 35 cultura e scienza del colore color culture and science | 06 | 2016 | 23 36 the restoration of color in the french historic cities: approaches, methods and experiences issn 2384-9568 conflict of interest the authors affirm that no interest in personal and/or financial influenced have affected their objectivity. the paper was written without conflicts, real or potential, with persons or organizations. bibliography [1] e. maccurdy (editor), the notebooks by leonardo da vinci, new york, george braziller, 1955, p. 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[1] g. brino, f. rosso, “colore e città. il piano del colore di torino: 1800-1850”, idea books, 1980. [2] c. boeri, “a perceptual approach to the urban colour reading”, colour&light in architecture_first international conference 2010_proceeedings, venezia, 2010. [3] j. p. lenclos, d. lenclos, “les couleurs de la france: maisons et paysages”, éditions le moniteur, 1982. [4] j. p. lenclos, d. lenclos, “couleurs du monde: géographie de la couleur”, éditions le moniteur, 1990. [5] j. p. lenclos, d. lenclos, “couleurs de l’europe: géographie de la couleur”, éditions le moniteur, 1995. [6] j. p. lenclos, d. lenclos, “maisons du monde: couleurs et décors de l’habitat traditionnel”, éditions le moniteur, 2007. [7] j. fillacier, “la pratique de la couleur”, dunod, 1986. [8] j. fillacier, b. lassus, b. urbanowicz, z. szydlowska, “recherche et application de la couleur dans ses rapports avec l’homme, panstwowe wydawnictwo naukowe, 1969. [9] g. gradenigo, “le laboratoire de la couleur. andré lemonnier”, payot, 2011. [10] v. m. schindler, “environnement polychromes au centre pompidou, exposition présentant notamment des œuvres de france et michel cler”, primaires ‘couleurs sensibles 173, 2ème édition, sous la direction de annie mollard-desfour et laurence pauliac, centre français de la couleur, pp. 40–43, paris, 2013. [11] chromatictownscape and colour words”, book of abstracts, ninth congress of the aic, 24-29 june 2001, pp. 103-104, rochester ny, usa, 2001. [12] m. cler, f. cler, v. m. schindler, “chromatictownscape: a manifesto. colour communication and cultural identity in urban planning and architecture”, proceedings of colour 2005, tenth congress of the aic, 8-13 may 2005, granada, spain, edited by j. l. nieves and j. hernándesandrés, 2 vols., pp. 405-408 granada, 2005. [13] m. cler, f. cler, v. m. schindler, “chromatictownscape. colour policy in the french ain region: colourstudies for towns, villages and valleys”, proceedings of colour 2005, tenth congress of the aic, 8-13 may 2005, granada, spain, edited by j. l. nieves and j. hernándes-andrés, 2 vols., pp. 1581-1584, granada, 2005. [14] d. steinmetz, “la coloration des façades. individualisme triomphant ou enjeu d’une « solidarité esthétique »?”, revue des sciences sociales, 2001, 28, pp. 103-109. 36 cultura e scienza del colore color culture and science | 06 | 2016 | 23 36 versaci a. and cardaci a. issn 2384-9568 doi:10.23738/ccsj.i62016.02 [15] aa. vv., “couleurs, lumières, matières: ambiances et cadres de vie”, caue de l’ain, 2011. [16] b. goyeneche, “les couleurs de nice et la restauration du paysage urbain”, éditions diagonal, 1993. [17] c. noury, “la colour dans la ville”, paris, éditions le moniteur, 2007. [18] d. brino, g. brino, “marseille et ses quartiers. couleurs et traditions en architecture”, edisud, 2001 [19] g. brino, “i colori e i materiali delle facciate di marsiglia”, colore e colorimetria. contributi multidisciplinari. genova, 11-12 settembre 2014, maggioli, vol. x a, pp. 249-260. [20] p. pinon, “de la ressemblance des secteurs sauvegardés entre eux”, sites et monuments, 2012, 219, pp. 27-32. [21] t. su, “le patrimoine urbain entre sauvegarde et pastiche: le cas de la ville de troyes”, habiter le patrimoine: enjeux, approches, vécu [online], presses universitaire de rennes, 2005. 28 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110103 'khrôma' the first software for management of the color and decoration plan for small historic villages filippo cherubini 1 , andrea casini 1 , costanza cucci 1 , marcello picollo 1 , lorenzo stefani 1 1 istituto di fisica applicata nello carrara del consiglio nazionale delle ricerche (ifac-cnr), via madonna del piano 10, 50019 sesto fiorentino (fi) corresponding author: filippo cherubini (f.cherubini@ifac.cnr.it) abstract the 'khrôma' project is aimed at creating the first software for the management of the color and decoration plan that can be applied to small historic villages. as is well known, italy is made up of many small historic villages that are described as "minor historical towns". they have been suffering for decades from a state of abandonment. the total lack of awareness of the importance of buildings within a wider historical-artistic context has generated the development of a methodology that can guide the qualitative and cultural appearances of the construction sites: namely, the color plan. however, the drafting of the color plan always requires competent professionals who are able to read and interpret the indications provided by the plan: this is the most important critical issue that makes the color plan an ineffective tool in the hands of nonexperts. an integral management on a digital platform would enable the application of the color plan for small historic villages, and would thus permit improved accessibility to the application of the plan as compared with the methodology currently in use. the proposed ‘khrôma’ software has the possibility to customize the functions and the database adjusting them to a territorial application on a specific area in question; its features include simple and intuitive graphical interface, independent functioning and accessibility that does not depende on any digital device. thanks to ‘khrôma’ software, it will be possible then to introduce a simplification in any given technicalbureaucratic procedure that can then be communicated to citizens as information regarding the upgrading process to their territory. keywords color, plan, digitization, architecture, khrôma, software received 19 april 2019; revised 05 may 2019; accepted 24 may 2019 citation: cherubini, f., cherubini, a., cucci, c., picollo, m., & stefani, l. (2019). ‘khrôma’ the first software for management of the color and decoration plan for small historic villages. color culture and science journal, 11(1), 28 – 34. https://doi.org/10.23738/ccsj.110103 mailto:f.cherubini@ifac.cnr.it 'khrôma' the first software for management of the color and decoration plan for small historic villages 29 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110103 1. introduction italian cities have been in crisis for decades because the resident communities have not been able to express the real potential that has been recognized for centuries in urban areas and that is linked to the value of local identity. the ancient cities were required to represent the power of those who governed both them and the social (and therefore economic) level of the inhabitants: the image of a rich, lively and powerful city corresponded to high levels of care and exploitation of the urban fabric, and the role of cities in extensive areas was declared by means of urban quality. in the modern cities, this awareness for the collective heritage has re-proposed ancient meanings of belonging and identity for all citizens, who find in the safeguarding of their traditions and in the promotion of their specificities an effective response to the banalization processes of the global market. for several decades, however, there has been a gradual loss of these types of knowledge in all parts of italy and also in many parts of europe: industrial processes have proposed materials and techniques that have simplified traditional local regulations, thus changing the appearance of buildings, which have gradually been stripped of their “skin” and consequently made them more commonplace; this inevitably leads to the cancellation of the ancient language of architecture. it then seems evident that the authentic appearance of the complex and varied language of architecture will be respected only if the original techniques and materials that are still present and testified to are re-appropriated. the protection of these values was already identified and well described in the 1987 washington charter [1], which complemented the 1964 venetian "international charter on the conservation and restoration of monuments and sites" [2].. therefore, it is of fundamental importance to preserve the authentic aspect of the complex and varied language of architecture that is respected only if the original techniques and materials, still present and witnessed in the historical centers, are reappropriated. a "preventive maintenance program" is necessary in order to safeguard the entire heritage of knowledge and languages and to determine a qualitative outcome for the restoration of every single building. at present, the complete lack of awareness concerning the importance of buildings within a wider historicalartistic context has generated the development of a methodology that can guide the qualitative and cultural appearances of the construction sites: namely, the color plan. the 'color plan' recognizes the historic rules of "doing" by re-approaching the material culture and a respect for traditions and for experiences handed down for centuries but abruptly interrupted starting from the post-war years in the name of a "modernity" that, from this point of view, has only impoverished us in cultural and qualitative terms. moreover, as also recommended by unesco in its guideline, 'the historic urban landscape,' implimented on 10 november 2011 [3], it is not only a question of protecting the intrinsic aspect of a single building or a small village / complex of houses but in a more general sense preserve that historical / urban aspect that characterizes italian landscape. the color plan is still the most suitable instrument for developing the valorization and promotion policies of historical architecture [4]. 2. the color plan the drafting of a color plan, whether it be for a very small village or for a large city, involves levels of knowledge of the place, the (overall) buildings and the materials that can only be attributed to an expert technician. these re-qualification plans develop issues that concern the maintenance status of the historic center, indicating critical points and unexpressed potentials. it will thus be necessary and essential to define how a color plan is drawn up and implemented. in addition to a knowledge of the place in historical-artistic and architectural terms, the research involved generally collects also traditional models of reference in order to reconstruct rules for the maintenance of the historical urban background. these elements can be briefly summarized as follows: • an abacus of materials and techniques • an abacus of the ornamentation elements • an abacus of the elements of urban decoration • a color abacus • a technical report • etc. this classification, which may seem reductive, actually makes it possible for a room, a space or even a single building to be correctly coded. if we take into consideration the color plans for the smaller historical centers (both those under unesco’s protection and those that are not), where the number of variables is less than that of large urban cities where elements of other cultures have always been incorporated, it is possible to think up a digital 'khrôma' the first software for management of the color and decoration plan for small historic villages 30 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110103 transposition of the color plan. the software in question, i.e. the subject of this project, is known as 'kroma'. it is important to remember that in italy the number of small, inhabited centers is extremely high (about 6000 villages have less than 5000 inhabitants) and these small hamlets often are not protected by any specific legislation, although the distinguishing characteristics of the builiding type and urban specificities to be protected may be recognized. 2.1. the color plan: critical issues color plans count on graphic tables, reports and rules, for a correct application of these methodologies. these may “range” from rough indications to specific ones. however, it is obvious that the critical aspects of this approach are indeed inherent in this system. in fact, the drafting of the color plan requires competent professionals who are able to read and interpret the indications provided by the plan. in addition, the application phase of the plan itself requires various meetings with the municipal administration in order to identify and find a point of agreement between the 'request' of the citizens/ technicians and the 'requirements' of the indications indicated in the plan. one of the most important critical issues of the color plan is based on this last step. this 'necessary' step with the local administration often slows down the procedures, and at times discourages citizens from participating in an improvement to the place in which they live. 3 objectives of the khrôma software the mission of the 'khrôma' project is to make the application of the color plan accessible to non-experts as well as professionals (in a first moment exclusively for the smaller historical centers, where the number of variables is lower). by digitally fixing the constraints indicated by the color plan, the goal is to enable accessibility to this plan by maintaining an active participation of the citizens involved. thus, even in the absence of qualified experts, individual citizens could become active participants in the redevelopment process, by going to operate independently but at the same time guided, on a digital platform. 4. description of the project managing the final results of the analyses of the graphic tables, of the relationship between the color plan, of the abacus of the elements and of the colors, is often quite difficult for those who are not qualified experts. the 'khrôma' project aims to achieve the 'participation' objective through a flexible, but controlled, interaction between the citizens and the program itself. in any case, the software needs an existing color plan that can indicate the general or specific constraints on the territory and the types of architecture submitted to analysis. this is necessary because the indications regarding colors, façades, type of materials, the various abacuses of the elements, and the decorative elements need to be previously analyzed and selected by the experts. therefore, it would be necessary to interpolate these elements, link them together, and then transfer them to a digital platform. the goal is to design a ‘digital’ container (not content) that would incorporate the analytic which can and must pertain only to a professional in charge of drawing up the color plan; it is the task of the professional to dictate criteria and rules with relative variations that the plan imposes and the program accepts. the program is structured within three macro areas. the first macro area is characterized by the identification and collection of data, by means of the compilation of a questionnaire, of the citizen / professional worker / company who assumes responsibility for the entire work process (fig. 1). the process takes place by means of digital procedures that by now already exist in most of the so-called digital administrations (digital signature, etc.). the second phase, the most important one, consists of identifying the building that is the object of the construction works, and of loading the graphic interface by means of which the user can manage the guided design process (fig. 2). at a subsequent stage, however, it would be necessary to develop a rigorous integration with the gis software, which already contains the most common operations related to geographical analysis, including a direct connection to the khroma software. this would allow the gathering of all data concerning the color plans loaded on the platform and would provide the graphic interface necessary for the users’ participation in the redevelopment process. some examples of interaction between gis and color plans aleady exist (particularly interesting is the project for the municipality of priverno in lazio [11]) but none of the programs include a study concerning the interaction with users by means of a graphical interface such as the khroma. 'khrôma' the first software for management of the color and decoration plan for small historic villages 31 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110103 fig. 1. first screenshot 'khrôma' the first software: data collection and responsibility assumption. fig. 2. preload of graphic interface with iron wire visualization and selection of elements to be modified. 'khrôma' the first software for management of the color and decoration plan for small historic villages 32 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110103 fig. 3. preloading elements of the color plan. fig. 4. facade unit diagram and related technical report. 'khrôma' the first software for management of the color and decoration plan for small historic villages 33 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110103 once the building has been identified, the program automatically uploads a schematic diagram of the façade so the user can immediately receive graphic correspondence on a screen. the following step provides the possibility of selecting only the elements that need to be modified in such a way that the program can automatically preload all possible permitted variants (colors, decorations, etc.) only for that façade. it is also possible, by means of the drag and drop system, to choose from among this series of elements, thus providing the user with a guided procedure that is already pre-authorized by the local administration (fig. 2 and fig. 3). the third and last step makes it possible to summaries data by printing a diagram of the façade and the design indications to be followed during the execution phase (fig. 4). the printing of the final report is very important, because it contains all the technical data necessary for performing a perfect job. the color codes and the relative coding system, materials and application techniques, any attentions to be taken into account during the work phases, etc., will be indicated in the said report. the main idea is, in fact, to provide a complete package with which, by printing both the façade color scheme and the technical report, the user can provide any operational-type company with all the details necessary for carrying out the work. it seems evident that more than the color printing of the facade, which serves merely as an example, it is the technical relationship that is of fundamental importance. it entails all the details that range from the colorimetric indications to materials to be used in the intervention to those that guide how the work should correctly be realized. it is worth remembering that the program would be implemented in small villages with mostly significant technical-administrative inadequacies. moreover, since these small villages are not directly under the protection of specific regulations, unlike, for instance, the historic center of florence safeguarded by unesco, they risk losing their distinctive features due to bureaucratic inertia. it then becomes the task of the professionals in charge of specific projects, together with the municipal administration, to control that the work performed corresponds to the requirements indicated in the technical plan. moreover, the software application has the following characteristics: • the possibility of customizing the functions and the database based on the territorial application area in question (the possibility of introducing any element of an abacus, color, single elevations and multiple façade units, etc.) • independent functioning (cloud software available 24/7) • accessibility from any digital device • simple and intuitive graphical interface 5. conclusions the 'khrôma' project is aimed at creating the first software for management of the color and decoration plan, i.e. one that can be applied to all small historic villages. as we have seen, starting from an analysis of the territory, it has been verified that the smaller historic villages have common characteristics that depend on the location of the place (for purposes of colors, abacus, materials, etc.). these characteristics, which are easily identifiable and classifiable only for these particular types of small towns, would enable an integral management on a digital platform and thus permit improved accessibility to the application of the plan as compared with the methodology currently in use. thanks to this software, it will be possible to introduce a simplification in a given technical-bureaucratic procedure that can then be communicated to citizens as information regarding the upgrading process to their territory. 6. conflict of interest declaration all authors declare that they do not have any conflict of interest realated to this paper. 7. funding source declaration all authors declare that they have no grant was received related to the activity published in this paper. 8. short biography of the author(s) filippo cherubini is a technician at the “nello carrara” institute of applied physics, national research council, italy. he has a bachelor of science degree in architecture and two postgraduate course at the university of florence. his interests include environmental restoration and architectural color studies. andrea casini msc in physics in 1968, has been a researcher at ifac-cnr from 1972 to 2010. expert in signal and image processing, for many years he has been developing imaging spectroscopic methodologies for the study of works of art in the "integrated spectroscopic methods for the diagnostics and monitoring of cultural and environmental heritage" project, with which he continues to collaborate as associate researcher. costanza cucci got her physics “laurea” and ph.d. in conservation science at the florence university. 'khrôma' the first software for management of the color and decoration plan for small historic villages 34 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110103 currently she is a researcher at ifac-cnr. her research focus is on spectroscopic techniques and dataprocessing algorithms applied to the fields of cultural heritage, environmental monitoring, and safety food controls. marcello picollo ph.d., is a researcher at ifac-cnr. his interests include color measurement, vis-nir hyperspectral imaging, and spot size uv-vis-ir spectroscopic investigations of 2d polychrome objects. lorenzo stefani is a technician in telecommunications at ifac-cnr. he is in charge of the development of hardware and software for computer-controlled instrumentation for the non-invasive and in situ study of artworks. references [1] https://www.icomos.org/en/what-we-do/focus/179-articlesenfrancais/ressources/charters-and-standards/159-charter-for-theconservation-of-historic-towns-and-urban-areas [2] https://www.icomos.org/charters/venice_e.pdf [3] https://whc.unesco.org/en/hul/ [4] casolari massimo, biasutti giulia, parma città che cambia tra identità e innovazione, maggioli editore s.p.a., 2006 [pag. 161-166] [5] centauro a.g., chiesi d., grandin n.c., caselli g., tazioli r., bassi s., opus studiorum/1, tecnologie e conservazione degli apparati pittorici e del colore nell’edilizia storica, firenze, lalli editore, 2008 [6] centauro a. g., chiesi d, grandin n. c., opus studiorum/5, centro storico di firenze metodologie ed applicazioni di restauro nella manutenzione dei fronti edilizi urbani, firenze, lalli editore, 2011 [7] centauro a. g., grandin n. c., restauro del colore in architettura dal piano al progetto, firenze, pacini editore, 2013 [8] rossi m., marchiafava v., colore e colorimetria contributi multidisciplinari vol. xi a, gruppo del colore – associazione italiana colore, 2015 [pag. 201-2 e pag. 299-308] [9] marchiafava v., colore e colorimetria contributi multidisciplinari vol. xii a, gruppo del colore – associazione italiana colore, 2016 [pag. 221-223] [10] raggi a., colore e colorimetria contributi multidisciplinari, 2005 [pag. 303] [11] http://priverno.risviel.it/ [12] bianchietti f., la facciata nell’edilizia storica: il piano del colore di verbania, materiali e superfici di recupero della città storica, milano, vangelista, 1993 [13] di campli a., di toro g., normativa tecnica d’attuazione del piano del colore del centro storico di sant’eusanio del sangro, sant’eusanio del sangro, 2006 [14] erario p., regolamento del colore della città di manduria, taranto, 2007 [15] piemontese l., progetto piano del colore: i piani del colore della provincia di latina, roma, gangemi, 2006 https://www.icomos.org/en/what-we-do/focus/179-articlesen-francais/ressources/charters-and-standards/159-charter-for-the-conservation-of-historic-towns-and-urban-areas https://www.icomos.org/en/what-we-do/focus/179-articlesen-francais/ressources/charters-and-standards/159-charter-for-the-conservation-of-historic-towns-and-urban-areas https://www.icomos.org/en/what-we-do/focus/179-articlesen-francais/ressources/charters-and-standards/159-charter-for-the-conservation-of-historic-towns-and-urban-areas cultura e scienza del colore color culture and science cultura e scienza del colore color culture and science | special issue on food color | 05 | 2016 21 issn 2384-9568 marina mastropietro von rautenkrantz marina.mastropietro@ progettocolore.com info@progettocolore.com colour in food packaging strategies and rules abstract originally made to prevent diseases due to poor sanitary conditions, food packaging is much more than this. it protects and communicates information not only about the food type (organoleptic properties for consumption), but also about the company and its corporate strategy. factories abide by strict packaging standards, focusing part of their resources to the packaging look, through psychology, marketing and budget based analysis. for a packaging to work, it has to safeguard the product, induce shopping, being read. on the sale shelf, the product has to be first seen, then chosen and finally purchased among many competitors. products has to catch the attention of the consumers in a small timeframe. moreover, since the consumer buys 75% by impetus and only 25% by programming, therefore it’s clear that purchasing means getting emotional. succeeding in selling means being able to give rise to emotions. colour in packaging is a wonderful salesman. it evokes emotions and is a quick, efficient and silent messenger. its “language” is ubiquitous, fully understandable and cheap. it is a powerful tool of nonverbal communication, able to strongly influence the mechanism for impulse buying. colour can attract attention in a very short time, transmitting product specific messages and creating strong brand identity. colour per se cannot meet all needs: the degree of saturation, brilliance and combinations between different colours change from time to time the end result. the creation of a seductive and attractive packaging is highly dependent on hue and hue combinations, context, the type of graphics and print format. the chromatic effect of a final package also depends on the material and texture. finally every colour evokes a different emotion and every colour evokes a different food (e.g. white for milk products). the language of colour, with its rules, requires a process of research and investigation that is difficult to fully understand, nevertheless, all food companies use colour in packaging with the strategy to increase their sales. keywords colour, emotion, food, packaging, strategy, sales, salesman citation: mastropietro von rautenkrantz m. (2016) ‘colour in food packaging strategies and rules’, cultura e scienza del colore color culture and science journal, special issue on food and colour, 05, pp. 21-30, doi: 10.23738/ccsj.i52016.03 received 07 july 2015; revised 22 february 2016; accepted 02 march 2016 cultura e scienza del colore color culture and science | special issue on food color | 05 | 2016 | 21 30 22 mastropietro von rautenkrantz m. issn 2384-9568 doi: 10.23738/ccsj.i52016.03 1. food packaging originally conceived to prevent diseases deriving from poor sanitary conditions, food packaging means more than a mere food package. a package both protects and communicates. upon inspection, consumers get information not only about the food type, its organoleptic properties, its beneficial properties, but also about the company and its corporate strategy. factories abide by strict packaging standards, focusing part of their resources to the packaging look, thus creating an analysis current, perching between psychology and marketing. the final aim consists in finding the best appropriate package for food, a compromise between budget requirements and the goal to stimulate the customer to purchase. 2. today’s market analysis and large scale retail store to understand the issues related to food packaging, it is necessary to examine the point of sale, the place where the product is displayed – among its many competitors. the attention of the consumer must be caught – the product must be sold. no serious company, wanting to loyalize its customers and sell its products would do it without knowing the weak and strong points of its point of sale [16]. if we consider a point of sale, putting aside the place, decor, design and colours, two are the fundamentals: • the precise location where the product is displayed (i.e. counter, shelving units, showcase) • the light source in a grocery store, food products are arranged following a marketing rationale. brand products and market leaders are placed on the upper shelves: these are popular brands, known by consumers because of ads, whereby price and quality are high. purchasing them is not easy: one has to look up to see them, and consequently raise one’s arm. private labels are placed on shelves at eye level, i.e. the lsrs brand. they represent a good quality/price compromise. they stand in the most favorable position for purchasing, because they are both at eye and hand level. in the lowest shelves: best price products, unknown brands, with a low quality standard and low price. purchasing them is uncomfortable: one has to bend down. whilst the brand and leader products have to launch an advertising campaign to keep their market share, private label and best price products do not advertise. moreover, to get the better strategical position, localization at eye level on the shelves (approximately 135 cm high, i.e. the average height of an italian woman), a company has to invest a lot of money [16, 20]. food companies have to compete in a overstocked market with very tight margins, where products are surrounded by all their competitors. these difficulties are even worsened by the trend of consumers to shopping quickly and with less and less time of consumers to spend inside a point of sale. for a brand product, there is a difficulty in being first seen, then chosen and finally purchased. moreover, the food company has to take into account that • every food product satisfies not only a functional need (hunger, thirst), that is primary need, but also a symbolic one, which is secondary: i eat in search of gratification, i eat because of my social position, i drink to have more energies etc. • the first and foremost driving force of purchase is emotional [16]. the consumer, in fact, buys something by impetus or by programming. all research institutes agree about the data that out of four products bought, three are bought by impetus and only one by programming [16, 17]. these figures, 75% by impetus and only 25% by programming, vary slightly depending on the point of sale , but it is clear that purchasing means getting emotional. at the mall, one does not read the label, but looks at the package! succeeding in selling means being able to give rise to emotions. 3. packaging: from mere package to real communicator efficient packaging and winning packaging for a packaging to work, it has to include three features [20]. these are: • it must adequately safeguard the product • it must induce shopping • it must be read. these features, skillfully combined by creative and advertising agencies may lead to successful result. if we consider only the graphical aspect, in applying this rule we simply represent the product by way of a picture or a sketch on the box containing the product (i.e. putting an orange on an orange juice tetra-brick). this kind of packaging has a limit, though: it satisfies cultura e scienza del colore color culture and science | special issue on food color | 05 | 2016 | 21 30 23colour in food packaging strategies and rules issn 2384-9568 only the primary need of the consumer, (hunger, thirst) but not his secondary needs [15, 19]. to satisfy all the requirements, the packaging has to stimulate not only the eye, but also other senses [1, 2, 3]. multisensorial messages evoke emotions, beneficial and pleasurable feelings during food consumption. moreover, it has to stand out among all competitors, express a strong personality and a special plus: appeal [7,13]. a fourth feature is then necessary, that is being seducting and charming: it must be “catching”! 3.1. the barilla case one of the first food companies to understand the need to use the term appetite as an ad on its box has been barilla, the italian pasta leader and popular brand name all over the world. in 1969, barilla started a re-styling operation of its packaging, known as “appetizing in the box”. the pasta box of 1956, a square shaped cardboard box chosen by the company, resulted in a market survey as being felt masculine, cold, industrial and dull, unable to provoke emotions, too outdated in a world of communications. the restyling was committed to lippincott&margulies, an international company specialised in visual communications. barilla decided to keep the colour blue, perceived as the company colour, which had been chosen by pietro barilla, founder of barilla in 1877, who started with his first pasta shop in parma, since the colour reminded of the so called “sugar paper” once used to wrap up the loose spaghetti. the 1956 box, light blue with a bulk of spaghetti on it, was hence restyled. the new feature consisted in reminding the appetite, showing pasta at the moment of its cooking process [7]. the barilla package, as displayed nowadays in a point of sale, has undergone another restyling around how the product is presented, which is shown at the very moment of its consumption, and not, as it was before, during the cooking, so to further evoke its appetizing properties. the light blue becomes a dark blue, a more refined and exquisite colour. pasta has been therefore “refined” from a large consumption italian main course to an exclusive and refined food product. figure 1 shelves layout in large scale retail with brands, market leaders, private labels and best prices figure 2 a winning packaging has to be “catching” cultura e scienza del colore color culture and science | special issue on food color | 05 | 2016 | 21 30 24 mastropietro von rautenkrantz m. issn 2384-9568 doi: 10.23738/ccsj.i52016.03 this new message has been supported by a massive advertising campaign all over the world. at the time, many famous testimonials like alberto tomba and steffi graf appeared in the ads, sitting in a luxury restaurant and ordering a nice barilla maccheroni dish instead of exclusive courses like caviar [7, 18, 19]. although minor changes have been introduced from time to time in the pasta packaging, according to the outcome of periodic marketing surveys [21], the barilla food company has always relied on two traditional features of its brand: • the blue chromatic code • the cardboard box moreover, barilla has never substantially modified the traditional image of the fork with a spaghetti knot, originally launched in 1985. in this picture pasta appears already deeped in sauce, ready to be tasted. the addition of a plastic window to the main side of the pasta package, originally used only in the foreign markets to provide a visual definition of the pasta type (not always known), is consistent with the food packaging strategy currently dominating in western countries: to show the content for its immediate identification and emphasize the manufacturer transparency and corporate integrity. one may observe: • barilla is the market leader and owns the colour code. • the best strategy for consumer goods mass market goods is appetite recall – displaying the scope on the package [15, 19]. colour: inspiring and preempting flavour several studies prove the great power of colours on consumers, inspiring and preempting the perceived flavor [812]. ernest dichter’s test (1964) envisages the following steps: • the same coffee poured into 4 cups • behind every cup were standing 4 different tin cans, in four different colours: brown, red, blue, yellow • a considerable sample of people were asked to depict the perceived flavour of all cups 3.2. market leader/premium product the lavazza/pellini case in 1964, the dichter’s test was made. in 1970 lavazza comes out with the qualità rossa which soon becomes the most sold coffee [13, 14]. lavazza’s choice is red, the colour conveying at best a rich and full flavour to consumers, adding the image of a hot coffee cup on the packaging. usually, a company wanting to launch a brand and acquire a market share from a competitor, figure 3 barilla cardboard box of 1956 showing the product, center: 1969 picture of pasta while cooking, right: 1985 pasta readyto –eat figure 4 a 2016 barilla typical spaghetti package cultura e scienza del colore color culture and science | special issue on food color | 05 | 2016 | 21 30 25colour in food packaging strategies and rules issn 2384-9568 • no vacuum-sealed package: instead, a cylindrical tin can labeled: 100% arabic – to highlight the value of the product (a tin can is definitely more valuable than a bag). this packaging has made possible pellini’s market repositioning so to address a different market segment, a “niche”, and increasing thus its sale price [13]. from consumer good, pellini became a premium product, an exclusive and high quality brand, supported by a polished image. illy had a similar approach with its elegant silver tin can [18]. 4. colour in packaging colour: a quick, efficient and silent messenger. moreover its “language” is ubiquitous, fully understandable and cheap! because of these features it is a powerful and extraordinary tool of non-verbal communication, able to strongly influence the mechanism for impulse buying. colour could be defined as “the has to differentiate itself. in this particular case, two were the options: • getting rid of the image recalling the function which will be only sensed or • breaking with the habits and use a completely unusual colour. lavazza and pellini coffee brands are the best example of different strategies to gain market shares and increase sales [19]. pellini’s packaging choice was almost imposed by the fact that they were obliged to design a new package opposed to that of lavazza [18]. to differentiate itself, pellini broke with the habits launching its product on the market (100%) arabic) with a new packaging, following three innovative rules: • no drawings of a cup • colour code change: red has been changed by dark brown, almost black (a “noble” colour which recalls the colour of a roasted coffee bean) tin can colour brown red blue yellow answer percentage and taster comment too strong note richer note lighter note too sweet note figure 5 pellini comes out on the market employing the breaking strategy cultura e scienza del colore color culture and science | special issue on food color | 05 | 2016 | 21 30 26 mastropietro von rautenkrantz m. issn 2384-9568 doi: 10.23738/ccsj.i52016.03 silent salesman” for its ability to attract attention in a very short time, transmitting product specific messages and creating strong brand identity [9]. if colour can “conquer” the eye in a second, the reaction that everyone has towards a specific colour is based on sensorial, emotional and cultural perceptions. it’s important to understand that a colour per se cannot meet all needs: the degree of saturation, brilliance and combinations between different colours change from time to time the end result. the creation of a seductive and attractive packaging is highly dependent on hue and the selection of its combinations, its context, the type of graphics and print format. the chromatic effect of a final package will also depend on the material, its nature and texture [13]. understanding the language of colour requires a process of research and investigation that is difficult to fully complete. 4.1 first assumption: all colours are allowed in nutritional packaging in this area wrong colours do not exist. it sounds surprising but this is due to the extremely broad number of competitors active in the market and faster and faster and emotions-based selecting criteria. it’s very hard to obtain and hold market shares and any tools and means are allowed [19]. 4.2 second assumption: any hue is useful provided that it’s properly utilized notwithstanding the unique features of an item (texture, shape etc.), its printing and graphic format and its marketing characteristics (target, end user, purchasing mechanism etc.), it’s important to remember that the message conveyed by a colour depends on individual, social and cultural values. many studies have been carried out on this topic: some have shown that people with light eyes and hair are attracted by packaging with light and soft hues while those with a darker complexion prefer darker and more intense colour shades [19]. indeed, johannes itten was the first to observe that people tend to select colour shades similar to their face hues while studying individual reactions to “armocromia” (colour harmony) at the weimar bauhaus [4]. in this respect, food industry has to implement different strategies based on the specific market they work in. changes and adaptations of product packaging, shape and colour are common to meet country specific expectation. minor modifications are often sufficient (i.e.: barilla has introduced in its pasta packages a small window to show its figure 6 from a study of j. itten: people with light coloured face prefer light and soft colours and the same is true for people with dark shades who prefer darker and strong colour contrasts cultura e scienza del colore color culture and science | special issue on food color | 05 | 2016 | 21 30 27colour in food packaging strategies and rules issn 2384-9568 content) or, sometimes, it’s necessary to change recipes or ingredients (salts, spices, sugar etc.). since 1941, we know that in western countries adults prefer blue (universal colour score, hans eysenk,1941) [6, 10] while in japan white is the favourite colour [15]. 5. how to identify a packaging colour to facilitate the choice of a colour code some criteria exist that help identifying the hue more appropriate for a given food. in a situation where any colour is allowed, two rules are more relevant: 5.1. the rule of coherence based on intuition and common sense, the “coherence” rule is similar to the criterion used to strengthen a food/beverage colour. the “coherence” rule is reliable because it doesn’t depend on social and cultural values. since the early sixties, its applications has enable the manufacturing of easy to interpret and sell items. at present, it represents a good starting point but it’s not sufficient (18). according to this rule the consumer is immediately informed and at the same time reassured on the food content. 5.2. the rule of colour induced messaging colours may stimulate perceptions and convey messages based on people experiences, models, social-cultural values and living environment. table 2 shows the main colours and food they are associated to. although this rule helps in developing packages, it needs, as in the case of the coherence criterion, additional approaches. on the basis of his studies on nutritional advertising (1949), max lüscher states that food which has to be perceived as natural and fresh requires red, yellow or warm hues to be seen as “living”[5]. using these rules, manufacturers try to offer consumers a product capable also to induce emotions. 5.3. the rules of market leadership as mentioned, the choice of a colour for a food package is based on corporate strategies that take into account market characteristics, competitors, target, positioning and market leaders. in the food industry sector, the colour selected by the leader set the rule and a colour code. the “barilla blues” is a typical example. when a food company plans to launch a product already introduced by the market leader, it has two options: -to align (me too) -to react (break the rule) in the first case it will attempt to imitate the leader packaging colour and graphic, this would look appropriate but would lack attractiveness and originality. the “me too” strategy is typical of private labels [15, 19]. the second options requires the development of tactics based on totally different products features, including colours so as to induce new visual identity (i.e.: red vs blue, white vs black). coca cola, the unchallenged market leader, has chosen red as its colour code. in this case the colour has multiple meaning: indeed ice blue would have been more appropriate for a figure 7this graph describes western adults favourite colours among the six major ones food food colour packaging colour milk e dairy products (yogurt, etc) white white water transparent, colourless transparent, colourless bakery products/pasta light yellow shades warm light yellow eggs and eggs derived products/egg powder strong yellow yellow egg pasta/egg noodle yellow bright yellow grain products light brown shades light brown, yellow cake, yellow/orange mozzarella/ fresh cheese white white coffee dark brown dark brown/ black fresh vegetables (salad) green green, warm green, yellow-green table 1“the rule of coherence”. the colour of the packaging is reminiscent of content cultura e scienza del colore color culture and science | special issue on food color | 05 | 2016 | 21 30 28 mastropietro von rautenkrantz m. issn 2384-9568 doi: 10.23738/ccsj.i52016.03 colour message conveyed to consumer food blue in its lighter shades: light blue, sky blue reassuring, harmless fresh refreshing undemanding, light reminiscent of water, air, sky milk and dairy products fresh cheese water ice cream fish frozen food decaffeinated coffee products for children ( when purchase decision makers is the mother) yellow: warm and light shades, orange shade warm fragrant friable freshly baked reminiscent of grain, yolk bakery products breakfast products pasta egg noodles green fresh refreshing genuine no additives / preservatives reassuring reminiscent of nature fresh vegetables salads table 2the rule of colour induced messaging refreshing drink. however, coca cola contains caffeine to energize consumers likely to be young and dynamic. coca cola is not only a refreshing drink but, chromatically speaking, supports a “sparkling” and active life style. the product, its packaging and colour share the same message: they are coherent and thus believable. pepsi cola, its major competitor, has been forced to break the rule adopting the opposite blue colour [13, 20]. 6. the strategic utilization of colours 6.1. colour as a product differentiator based on its strong symbolic value, a colour code can better identify different types of products in the food industry [17]. colour is a food labeling tool (table 3). figure 8 according to “the rule of colour messaging” the packaging of decaffeinated coffee is often blue or light blue figure 9 the align strategy is usually used by private labels to imitate market leaders. here esselunga aligns to barilla figure 10 applying the breaking strategy pepsi cola enters the market using the blue colour 8 9 10 cultura e scienza del colore color culture and science | special issue on food color | 05 | 2016 | 21 30 29colour in food packaging strategies and rules issn 2384-9568 6.2. colour to identify different varieties of the same products a colour code, rather than specific shapes and/or graphics, serve to differentiate among variations of the same products, being more recognizable by consumers. hues are changed so as to represent chemical or physical features (taste etc.). some examples are reported on table 4 [19]. common people adopt highly represented colours as colour codes, as shown in specific food products: in the case of “owen” products, red means salty and blue bland while for sauces, spices and dressing red means tasty, hot vs blue which indicates mild, healthier. even for mineral water red and blue means strong or light sparkling [18]. table 3 colour as a food differentiator table 4 using colour to identify basic products and its extension line products type of product colour conveyed message premium products “noble” colours: golden, silver, black, dark green, dark blue, dark brown nobility and finesse best price products red, orange induce to stop, stimulate purchase and appetite bio products green freshness, genuinity, no additives light products same colour of the basic product but in its lighter shades the package colour, identical to the basic product, is only “lightened”: the product appears lighter and low-calorie food packaging colour evoked message basic product milk pasteurized whole milk pasteurized skimmed milk light blue light red freshness lightness basic product crackers salted crackers unsalted crackers flavored crackers whole grain crackers red blue green light brown tasty, flavourful healthier aromatic content high -fiber figure 11 colour codes acquired over time: red for salted/hot/sparkling and blue for unsalted/mild/still cultura e scienza del colore color culture and science | special issue on food color | 05 | 2016 | 21 30 30 mastropietro von rautenkrantz m. issn 2384-9568 doi: 10.23738/ccsj.i52016.03 bibliography [1] goethe, j.w. zur farbenlehre,1810 [2] ostwald, w. die farbenfibel, leipzig, 1916 [3] hickethier, a. farbenordnung hickethier, hannover, 1952 [4] itten, j. arte del colore, saggiatore, milano, 1965 [5] luescher, m. il test dei colori, astrolabio, roma, 1976 [6] porter, t. architectural color, new york, 1982 [7] ganapini, a.i. e gonizzi, g. barilla, cento anni di pubblicità e comunicazione, archivio storico barilla, parma, 1994 [8] tornquist, j. colore e luce, unicopli, 1999 [9] luzzatto, l. e pompas, r. il colore persuasivo, il castello, maggio 2001 [10] pastoureau, m. blu, storia di un colore , ponte alle grazie, 2002 [11] pawle, j. e delfaud, d. how does your cappuccino feel? using synaesthesia to create a visually interactive experience of flavour, esomar congress, istanbul, 21-25 september 2003 [12] luzzatto, l. comunicazione personale, accademia di comunicazione, milano, settembre 2006 [13] mancini, v. comunicazione personale, vittorio mancini&associati, 2007 [14] vittorio mancini&associati, data on file, milano, 2007 [15] ostidich, d. comunicazione personale, marketing&trades, milano, 2007 [16] ostidich, d. e meo, c. come acquistano gli italiani, il sole 24 ore libri, 2008 [17] mastropietro, m. e dioguardi, l. the colour as design instrument to increase the workers welfare in the ready-to-use fruits sector, xxxiii ciosta-cigr section, v conference and iufro workshop, reggio calabria, 17-19 june 2009 [18] mastropietro, m. il colore negli alimenti e nel packaging alimentare, seminario di konica minolta, stazione sperimentale per l’industria della conserve (ssica), parma, 21 giugno 2011 [19] mastropietro, m. le regole per colorare il food e beverage, settima conferenza nazionale del gruppo del colore, università la sapienza, roma, 15-16 settembre 2011 [20] mastropietro, m. uso del colore per migliorare l’efficienza e il comfort nei siti produttivi alimentari, tesi di dottorato, scuola di dottorato di ricerca innovazione tecnologica per le scienze agro-alimentari e ambientali, dipartimento di ingegneria agraria, università degli studi di milano, anno accademico 2010/2011 [21] pagliari, r. comunicazione personale, internal communication & corporate archive, archivio storico barilla, parma, 2016 microsoft word 1501ed color culture and science cultura e scienza del colore ccsj volume 15 number 1 2023 issn 2384-9568 color culture and science journal cultura e scienza del colore ccsj jcolore.gruppodelcolore.it issn 2384-9568 doi: 10.23738/ccsj.00 ance: e227716 registrazione tribunale di milano n. 233: 24/06/2014 anvur agenzia nazionale valutazione sistema universitario e ricerca apej academic publications ejournal base bielefeld academic search engine dbh database for statistikk om høyere utdanning doaj directory of open access journals ezb elektronische zeitschriftenbibliothek regensburg jurn search tool for open access content road directory of open access scholarly resources volume 15, number 1, march 2023 doi 10.23738/ccsj.150100 publisher gruppo del colore – associazione italiana colore www.gruppodelcolore.org registered office: piazza carlo caneva, 4 20154 milan (it) peer review process all articles submitted to the color culture and science journal are peer-reviewed according to the following procedure: first review level the associate editors evaluate each article to determine if the topic and content are of interest to the journal. once the article passes the initial review, the associate editors select several reviewers from the editorial board based on their expertise in a particular subject area or topic. second review level two or three experts review each article with a blind peer-review process where the reviewers are kept anonymous. reviewers are asked to evaluate the manuscript based on the following criteria:  originality  relevance to journal's aims and scope  technical merit and/or validity  soundness of methodology  completeness of the reported work  conclusions supported by the data  correct acknowledgment of the work of others through reference  effectiveness of the manuscript (organization and writing)  clarity of tables, graphs, and illustrations  importance to color researchers  relevance to color practices if the article is accepted with major revisions, the author(s) are asked to improve the article according to the reviewers' suggestions. the revised article will then be submitted for further review. after collecting the reviewers' reports, the associate editors recommend the acceptability of the article to the editor-in-chief. editor-in-chief maurizio rossi (politecnico di milano, it) deputy editor alice plutino (università degli studi di milano, it) associate editors josé luis caivano (universidad de buenos aires, ar) vien cheung (university of leeds, uk) marco gaiani (alma mater studiorum università di bologna, it) robert hirschler (serviço nacional de aprendizagem industrial, br) agata kwiatkowska-lubańska (academy of fine arts, kraków, pl) marcello picollo (ifac-cnr, it) verena m. schindler (chair aic s.g. environmental colour design, ch) renzo shamey (nc state university, usa) editorial board members the complete and updated list of the editorial board members involved in the peer review process is available on the ccsj website: http://jcolore.gruppodelcolore.it/ojs/index.php/ccsj/about/editorialteam topics the ccsj accept papers on a wide range of topics on color, including and not limited to the following: 1. color and measurement/instrumentation. colorimetry, photometry and color atlas: method, theory and instrumentation; quality control and food coloring, dyes, organic and sustainable color. 2. color and digital. reproduction, management, digital color correction, image processing, graphics, photography, film and video production, printmaking and 3d print, artificial vision, virtual reality, multispectral imaging, data visualization. light field imaging. multi-sensor fusion. color localization, recognition, hdr imaging, adas systems. 3. color and lighting. metamerism, color rendering, adaptation, color constancy, appearance, illusions, color memory and perception, color in extra-atmospheric environments, lighting design, lighting technologies, visual comfort. 4. color and physiology. mechanisms of vision in their experimental and theoretical aspects, color vision and color appearance, deficiencies, abnormalities, clinical and biological aspects, synesthesia, health, well-being. 5. color and psychology. phenomenology of colors, color harmonies, color & form, perceptive, emotional, aesthetic, and diagnostic aspects. 6. color and production. food and beverages, agriculture, textiles, plastic materials, ceramics, paints, gemology, color in the food industry. 7. color and restoration. archaeometry, painting materials, diagnostics, and conservation techniques, restoration, and enhancement of cultural heritage. 8. color and environment. representation and drawing, urban planning, the project of color, architecture, interior design, landscapes & horticulture, color and architectural syntax, territorial identities, biodiversity. 9. color and design. furniture, cmf design, fashion, textiles, textures, cosmetics, food design, museography. 10. color and culture. arts and crafts, history, philosophy, aesthetics, ethno-anthropology, graffiti, geology, sociology, lexicology, semantics, anthropology of vision, food culture and heritage, color naming. 11. color and education. pedagogy, didactics of color, aesthetic education, artistic education. 12. color and communication/marketing. graphics, communication, packaging, lettering, exposure, advertising. 3 color culture and science journal vol. 15 (1) issn 2384-9568 table of contents editorial 5 maurizio rossi a review based on oled lighting conditions and human circadian system 7 ayse nihan avci and saadet akbay doi: 10.23738/ccsj.150101 virtual interior environment: influence of colour on the sense of immersion 13 firdevs gökmenoğlu and saadet akbay doi: 10.23738/ccsj.150102 a comparative study of lipstick shades preferences by geographical areas 19 hélène de clermont-gallerande, emmanuelle mauger and nicolas rolland doi: 10.23738/ccsj.150103 colour, texture, and luminance: textile design methods for printing with electroluminescent inks 27 delia dumitrescu, marjan kooroshnia, erin lewis and kathryn walters doi: 10.23738/ccsj.150104 imaging colorimeters to evaluate camera monitor systems image quality 35 cristian bonanomi and kedar sathaye doi: 10.23738/ccsj.150105 an experimentation on children’s colour preferences in generic terms and applied to a school context 42 camilla giani and cristina boeri doi: 10.23738/ccsj.150106 an analysis of chromatic and luminous environment of healthcare establishment. 48 estelle guerry doi: 10.23738/ccsj.150107 4 color culture and science journal vol. 15 (1) issn 2384-9568 enquiry into the colours of the mogao murals at dunhuang from the sui dynasty, the tang dynasty and the five dynasties period 57 elza tantcheva-burdge, zhaohua lei and vien cheung doi: 10.23738/ccsj.150108 “perpetual plum”: colour naming strategies in maybelline’s lip products 69 isabel espinosa-zaragoza doi: 10.23738/ccsj.150109 the promise of color in marketing: use, applications, tips and neuromarketing 76 alessandro bortolotti, loreta cannito, stefano anzani and riccardo palumbo doi: 10.23738/ccsj.150110 book review: i colori sono di tutti? 22 domande curiose sul colore 86 marcello picollo 5 color culture and science journal vol. 15 (1) issn 2384-9568 editorial dear readers1, with volume 15, issue 2, we enter our journal's tenth year. since our start, we have published 14 volumes for 17 issues. i wish to remember that since 2019 the ccsj has been based on ojs for better indexing of the published articles through the oai-pmh protocol. in 2020 we refined our archiving policy to guarantee long-term access to our issues, making agreements with the biblioteca nazionale centrale di firenze. starting in 2015, we applied for the blind peer review, and in 2016 we used the doi system. as you can see on our home page, our journal is indexed and included in the databases of anvur, apej, base, dbh, doaj, ezb, and jurn. we are constantly working to improve this in the future. i remember we are a "diamond open access"; the journal is free for readers and authors. this result is possible thanks to the voluntary support of many people around the world: the reviewers of the editorial committee, the associate editors, the deputy editor alice plutino, andrea siniscalco, the vice-president of our publisher, associazione italiana colore, for the graphic support and last but not least clelia gotti for her work in the editorial office. as you can also read in this issue, our journal's peculiarity is to collect papers on color and related areas in a multidisciplinary way. in our complex peer review process, we have articles ranging from the science of colorimetry to the culture of color in art history. these papers have very different styles and ways of writing, as rich and multidisciplinary as the team of peer reviewers on our editorial board. we have three papers with studies regarding color and lighting indoor. ayse nihan avci and saadet akbay, in their paper a review based on oled lighting conditions and human circadian system, present a literature review on how oled lighting, instead of the more well know leds, can influence the human circadian system in terms of different characteristics of lighting in an indoor environment. in the article virtual interior environment: influence of colour on the sense of immersion, firdevs gökmenoğlu and saadet akbay investigate how the sense of immersion in virtual interior environments varies based on hue, saturation, and lightness and examine the extent to which color dimensions influence the sense of immersion in virtual environments. they present interesting findings regarding the effects of lightness variations. a study on children's color preferences, applied to a classroom environment, in generic terms and a school context, through an experiment in digital simulation with the cave and digital color samples, is presented by camilla giani and cristina boeri in their paper an experimentation on children's colour preferences in generic terms and applied to a school context. 1 colour (uk) or color (us)? in our jurnal, both terms are allowed as long as they are congruent within an article. the exception is given by this editorial in which i use color as on our website. still, sometimes colour could appear to respect the original title of a paper. 6 color culture and science journal vol. 15 (1) issn 2384-9568 the importance of color in manufacturing and marketing is presented in four articles ranging from the lipstick market to textile and neuromarketing. in the paper a comparative study of lipstick shades preferences by geographical areas, hélène de clermont-gallerande, emmanuelle mauger, and nicolas rolland present research, based on principal components analysis, regarding the 20 best-selling chanel lipsticks in france, italy, the uk, the usa, asia, and south america. they discovered that italy and france are the markets most representative of lipstick shades. isabel espinosa-zaragoza, in the article “perpetual plum": colour naming strategies in maybelline's lip products, presents a study dealing with the color terminology for lipstick color names by maybelline through the word formation processes and the imagery exploited. the analysis revealed the predominance of two nomenclatures: morphosyntactic and semantic, and the paramount importance of color terminology in cosmetic verbal identity. the article colour, texture, and luminance: textile design methods for printing with electroluminescent inks, written by delia dumitrescu, marjan kooroshnia, erin lewis, and kathryn walters, presents research exploring the properties and potential of three textile print methods for electroluminescent inks as smart colors for textiles, proposing a set of techniques to create various color mixtures and design complex patterns. we also have a review of scholarly articles focusing on the use of color in marketing, identifying main features and highlighting limitations. practical implications and future directions are outlined, with a particular interest in neuromarketing, presented in the paper the promise of color in marketing: use, applications, tips and neuromarketing by alessandro bortolotti, loreta cannito, stefano anzani, and riccardo palumbo. in the field of colorimetry, cristian bonanomi and kedar sathaye focus on the optical performance evaluation of a camera monitor system for (advanced driver-assistance systems (adas) in terms of the lighting system, test patterns, imaging colorimeter and software, with measurement according to standard iso16505:2019, in their article imaging colorimeters to evaluate camera monitor systems image quality. finally, an important historical study, enquiry into the colours of the mogao murals at dunhuang from the sui dynasty, the tang dynasty and the five dynasties period, is presented in the paper by elza tantchevaburdge, zhaohua lei and vien cheung. they have done historically enquires on the appearance of colors used in the representative system of the mogao murals at dunhuang, in three dynasties, to better understand these murals as emblematic of chinese civilization. enjoy the reading. march 2023 the editor-in-chief maurizio rossi full professor of design politecnico di milano 57 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110107 industrial colour invention: a comparative analysis from the perspective of the colourist designer lina perdomo 1 1 university toulouse jean jaurès, france. lina.perdomo@etu.univ-tlse2.fr corresponding author: lina perdomo (lina.perdomo@etu.univ-tlse2.fr) abstract in this article a comparative study of two different colour invention processes in the paint and coatings industry from the perspective of the colourist designer is presented. our research is based on a thorough analysis of colour communication tools and on empirical data from interviews with actors of two leading companies from latin america and europe. in both processes we find two distinct sets of expertise. in the first one we identified, the primary driving expertise is from the field of engineering and marketing. in the second one, we find the expertise of the colourist designer, from the field of applied arts, supported by marketing considerations in an iterative process. in our work we study how these different approaches impact the resulting colour palettes, that is, the product ranges reaching the market. our results point out an ongoing evolution in the invention of colours, strongly linked to the introduction of the artistic sensitivity of the colourist designer, in an industrial context. keywords colourist designer; paint and coatings industry; colour invention; colour communication tools; comparative analysis. received 26 july 2018; revised 20 october 2018; accepted 10 january 2019 citation: perdomo, l. (2019). industrial colour invention: a comparative analysis from the perspective of the colourist designer. color culture and science journal, 11(1), 57–66. https://doi.org/10.23738/ccsj.110107 mailto:lina.perdomo@etu.univ-tlse2.fr mailto:lina.perdomo@etu.univ-tlse2.fr industrial colour invention: a comparative analysis from the perspective of the colourist designer 58 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110107 1. introduction colour communication tools, known as fan decks in the industrial context, have an essential role to play for market success in the paint and coatings industry. in this article we present a comparative study of two different approaches to develop and communicate colours in the paint and coatings industry and the resulting colour communication tools from the perspective of the colourist designer. colour invention processes in this industry have to take into account a variety of considerations and constraints from vastly different domains and contexts. among these there is the field of marketing, corresponding to a mostly empirical, sales-oriented approach to colour, having received considerable attention from the scientific community (journal of international marketing, 1993 2012) over the last decades. on the other hand, approaches of chromatic design from the field of applied arts have not been studied in an industrial context from the perspective of poietics. this study aims to partially close this gap. our research is firmly based in the framework of action research in arts (liu, m., 1997 ; caumon, c., et al., 2016), based on interviews (ethnological approach, see copans, j., 2011) with the main actors involved in the design of these tools and their analysis from the perspective of poietics (passeron, r., 1989, 1996). the key actors and the colour palettes themselves will be our main object in this study that is based on data from two paint and coatings companies who are market leaders in their respective territories. we are going to designate the first one as company a (operating in latin america), and the second one company b (operating in europe). the fan deck as a colour communication tool of reference in every paint and coatings industry is designed to carry out a particular function, which is not only to simply communicate colours and to facilitate the act of selling them but to activate the imagination of a specific user. the analysis of these tools allows us to identify the main interests, questions and concerns involved in every phase of the creative processes, supported by interviews we conducted with the relevant creative actors. the key actors involved in these processes develop colour communication tools following their individual methods to optimally address the specifics of their market environment and its particular cultural traits. the interviews we conducted allowed us also to gain unique insights into how the results of market research impacts the individual creative process in each company and how it drives localised colour innovation processes adapted to the respective market environments. it is important to say that our interest is not only about cultural influences that we identify at the heart of the creation of each tool, or the strong impact of the sensible and differentiated perception of colour individual to each actor and her or his specific set of expertise. our main interest is, firstly, to investigate how an actor from an artistic background, the colourist designer, operates under the constraints of an industrial environment. secondly, how the very different background of another actor (engineering/marketing) in the equivalent position at another company influences his creative process. both creative settings have to the best of the author’s knowledge never before been investigated in the field of poietics. identifying the impact of two markedly different sets of expertise of the involved actors helps us to respond to our final interest, which is to identify the artistic complexity that is involved in the process of defining colour phenomena in this industry. the art of placing colours together will allow us to understand better how today’s key actors manipulate colour parameters, how they interpret them but especially how all of this will help us in our intention to evolve today’s creative process by implementing in the industry creative methods of the colourist designer’s scientific and practical expertise. questioning and analysing our own perspective and the professional experience from the field of engineering and marketing will lead us to new insights in a field still little explored from the perspective of poietics. 2. methodology we have conducted, in a first step, interviews with the key actors involved in the design of colour palettes and the corresponding fan decks as they are the most important colour communication tools in both companies. the detailed interviews allowed us to gain a deeper understanding of the terrain and have provided the data for a direct comparison of the actors’ expertise and the importance of their artistic approaches. in a second step, a detailed analysis of both companies’ main fan decks has allowed us to build hypotheses about how the act of creation and the individual perspective of the involved actors reflects their specific expertise as well as the cultural environment of the respective target markets. considering the complexity of the colour phenomenon (pogacar, v., 2012; ladnytska, o., et al., 2015), the analysis of colour communication tools in an industrial industrial colour invention: a comparative analysis from the perspective of the colourist designer 59 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110107 environment implies a significant reflection on categorisation and classification. the objective of our analysis has thus been to identify the main systematics employed: systems of classification (chromatic groups), a quantitative analysis of the colours present in the considered tools and the used approaches of nomination and codification (we base ourselves on the anthropologic work of (berlin & kay, 1969), always taking into consideration the whole creative process. as a reference and to determine the colorimetric limits specific to each chromatic group, we use the ncs (natural colour system). our chromatic data is translated using the ncs digital atlas and the ncs colour palette itself to identify where the chromatic groups (colours) are located in a standard color space. we take into account both the horizontal, which is identical to the chromatic circle, showing the hue, and the vertical section of the colour space, corresponding to the nuance. our general approach is expressed in the words of rené passeron (rené passeron, 1989) as, “a normative reflection on the act of creation” in the context of our research in between the realm of the arts and the industry. it is in this manner that the confrontation of the creative reflection we find in each terrain with our own creative process makes us consider the specific codification and classification of each terrain as a key factor in our analysis of how these different approaches impact the resulting colour palettes that reach the market. 3. results i analysis of the interrelation between creative process and communication tools in this section we give an overview of how company a and company b function when it comes to the development of their colour palettes and the design of their fan decks. communicating on all aspects of colour and identifying the most appropriate qualifiers and nuances that correspond to the specificities of a given market are the key principles when it comes to the operating modes (opus operandi (passeron, 1989)) playing an essential role in each reflection about colour. following our analysis of the conducted interviews, the actors involved in the creative process agree with regard to the analysed tool appearing in the industry as an essential element that has to help and guide every customer or professional to make a colour choice. however, it is interesting how, in the case of company b, we can identify an approach in which the fan deck is seen as a tool that is endowed with the power to bring a poetic aspect into people’s lives by proposing a unique system of nomination in combination with a simplified system of codification. in comparison, in the case of company a we find a tool of similar general characteristics that has, however, been designed from a point of view closer to the fields of engineering and marketing and in which, instead of proposing only one system of colour nomination, two different numeric systems of colour codification can be found, and furthermore a more poetic system of colour names. this particular choice has been made to appeal at once to the three major user groups of the tool. these two different methodologies, each one developed over a period of one year of analysis and practical experiments and corresponding to mostly marketing-oriented strategies bring up a variety of questions about the position of the poetic dimension in each creative process and its impact on the final result. paint & coatings industry company a (latin america) colour tool created in 2014 company b (europe) colour tool created in 2015 expertise of the creative actor engineering & marketing colour design & fine arts colour comm. tool classification 8 chromatic groups (pastels, reds, oranges, yellows, greens, blues, purples, neutrals-earthy) 8 chromatic groups (whites, reds, oranges, yellows, greens, blues, purples, neutrals) colour comm. tool nomination 3 different codes : 2 numerical codes + 1 descriptive code 1 numerical code table 1 analysed properties of industrial colour communication tool design processes industrial colour invention: a comparative analysis from the perspective of the colourist designer 60 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110107 anticipating the specific function of each of the tools helps the creative actors to define its performance, at the same time transforming a multitude of colours, taking into account either cultural particularities the dominating factor we identify in company a (creative actor expert in marketing/engineering) or taking a more scientific approach, such as we find in company b (creative actor expert in arts/colour design). it is understandable that marketing aims to respond to cultural particularities, since its principal objective is customer satisfaction (madden, t., et al., 2000), contrary to the artistic approach that aims for creative freedom. for a paint and coatings company, developing a unique colour tool including a proprietary codification and/or nomination system represents a significant investment, thus this step is taken typically only by companies that enjoy a solid market position. this is the case for both of the companies that are the object of our study. according to our interviews, the decision to create their own colour systems has been taken after long years of experience. for years, each of them worked with adopted systems and eventually with various suppliers from different parts of the world. the fan deck of company a was conceived in 2014 and it represents the first own tool developed by the company. this is the case as well for company b (first proprietary fan deck and colour classification system developed in 2015, described as an international colour system). in table 1 we identify the main characteristics that are the focus of our study and that we consider as the principal factors involved in the design of the considered colour communication tools. note that it is the very existence of these tools that renders accessible industrial colour universes to an objective analysis. as the author of (guy lecerf, 2014) puts it, “the activity of the industry [makes us] think colour as something objective. [...] colour [in the industry] becomes a phenomenon accessible to analysis, classification and reproduction”. however, being subject to methods of widespread mass market communication, it is inherently designed to appeal to a large number of individuals, for whom colour has to be perceived as something subjective that brings poetics into their everyday lives. it is in the presence of this tension between objectivity and subjectivity that the design process of colour palettes and the analysed tools takes place. note that the categorisation into chromatic groups as well as the system of nomination/codification are the company’s. to first better understand how colours are structured in the industry and to identify how international colour systems influence the classification of colours in each tool, we analysed every chromatic group (eight in total) among the 1407 colours of company a and the 1650 colours of company b (a total of 3057 colours). 3.1 fan deck company a (latin america) – 1407 colours (colour tool a) the colour tool a features a cover full of coloured flat geometric shapes, mostly triangular. the colours, mapped into the ncs colour space, have a saturation between 70% and 90%. the fan deck is of standard size of 4,7x26cm (in comparison with some other industry fan decks which measure 5x20,3cm, 5x22,8cm, 5,1x25,4cm, 5x26,5cm and 5x29,2cm) and starts off on the first pages with a succinct explanatory introduction to the basics of colour theory based on the chromatic circle, followed by an explanation of the colour codes employed throughout the tool. it is starting from the softness and delicacy of pastel colours that our chromatic voyage then begins. using the ncs colour system as a reference, we observe that the whole chromatic range of the corresponding colour family of the ncs colour circle (reds, oranges, yellows, greens, blues and violets) are covered in the same order as we find it in multiple cross-cultural investigations which have typically found a wide variation in color-naming systems (bornstein, 1973). every colour is situated at the top of the grey scale within the ncs colour triangle (which are the whites (w)), having less than 10% of black (s) and a saturation (c) between 2% and 10% for every colour. (see fig. 3) inside this group we also identify, in exactly the same order, the chromatic groups that constitute the corpus of the tool with the exception of the neutral-earthy colours group which appears at the end and represents the largest chromatic group. it should be noted that in the neutral-earthy colours group we also identify the entire chromatic range of the ncs colour circle. this time, in the ncs colour triangle we see that the lightness of every colour is situated between white (w) 10% and black (s) 100%). in contrast to that, the saturation value (c) falls between 2% and 20% for every colour, rendering this family of colours rather greyish and dark. as mentioned above, the development process of this tool is conducted by a creative actor whose formal expertise is based in engineering, complemented by professional experience in the colour industry in a marketing context. colour as an objective entity (guy lecerf, 2014) has to correspond to customer needs identified by market industrial colour invention: a comparative analysis from the perspective of the colourist designer 61 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110107 research conducted by the company a [1] . however, not only colours corresponding to these objective requirements can be identified in the analysed tool. the sensibility of its creator expresses itself by the choice of an at the same time rhythmic and linear ordering of colours inside every chromatic group. this approach appears to be very intuitive, as colours can be found without intricate knowledge of the underlying systematic. the overall ordering of colours clearly makes reference to the newtonian colour circle, a universe intuitively familiar to a large part of the population, irrespective of culture, religion or education. each page contains different samples with the same hue, from the lightest to the darkest. in this way pages with light colours (high lightness and medium saturation) and bright colours (high lightness and saturation) are confronted with pages with more vivid colours (medium lightness and high saturation) and dark and deep colours (low lightness and saturation), creating a colour symphony where far reaching delicate harmonies are enriched by more tonic and dominant notes. this is confirmed in our comparative analysis where chromatic groups proposed in the fan decks have been located in the ncs colour space as illustrated in our case study of the chromatic group of yellows (see section 4.1). the rhythm is always systematic, but the transitions from one group to the following are always smooth, giving the impression of a continuum of gradually shifting shades. another important point of the analysis, as we mentioned above, is the colour nomination. the chosen method is to confront descriptive codes with numerical codes. this multiple colour identity responds at once to the variety of potential users of the tool (numerical codes tend to dominate in professional environments, while in retail typically descriptive nominations are preferred) and reinforces each colour’s brand identity. 3.2 fan deck company b (europe) – 1650 colours (colour tool b) the second fan deck, also roughly following the standard size of this kind of tools (5,3x31cm) but a little larger than the colour tool a, exhibits distinctly different features in several aspects. even if both tools use geometric shapes mostly triangular for their cover, this one only shows different shades of blues, purples and reds, with a saturation (c) between 40% and 70%. these colours (more sophisticated than those of the fan deck a) are applied in a gradient fashion leading to a 3d effect pattern that is then expanded on the back page of the tool in green, yellow and orange shades. but even if they respond to the same demand and we see a similar physical appearance, a simple look at the tool reveals that we are exploring a very different colour universe. the first five pages present an introduction to the general spirit of the tool that includes an explanation of the system of classification used (how colour families are grouped, how the colours of each family are divided into different levels of saturation (from bright to shaded colours), how each page contains different samples with the same hue, from the lightest to the darkest, with exception of the whites the best selling group where the colour samples are bigger than the other ones in order to improve visualisation), and leaves the reader with the impression that we are inside a systematic classification that however tries to leave freedom and breathing space to the imagination of the user. the first chromatic group also begins with soft and delicate shades, this time named ‘whites’. in comparison with colour tool a, this first group does not introduce the whole range of colours that we find in the tool as it covers only five colour families of the ncs colour circle (-g80y, g90y, -y, -y50r, -r). as the pastel group of tool a, in the ncs colour triangle, they are all situated at the top of the grey scale (w), this time having less than 5% of black (s) and of saturation (c). this first group corresponds to what is designated in french as ‘blancs colorés’, i.e. we do not find pastels declined in different colour families here, but this first chromatic group is about the coloured lightness provided by the white, in a quite subtle way. then, in the next group, subtle reds appear, followed by oranges, yellows, greens, blues, purples, ending with the group of neutrals. as for the colour classification inside every chromatic group, each page contains, similar to the first fan deck different samples with the same hue, from the lightest, on top of the page to the darkest. the difference here is that each chromatic group is divided into different levels of saturation and lightness. from bright colours to rich (high saturation and lightness medium and high), light (medium saturation and high lightness), muted and shaded (low saturation and all levels of lightness) colours. as a consequence of this choice, the rhythm present in the transitions from one chromatic group to another is markedly less subtle and more abrupt. the gradually changing shades we find in the tool a in the transitions between groups can be found here in the ordering of colours inside each chromatic group. a colour symphony is also experienced in here, but the difference is that there are no tonic and dominant notes that disrupt the rhythm, leading to a harmonic, smooth and delicate composition in perfect accordance with consumer preferences. industrial colour invention: a comparative analysis from the perspective of the colourist designer 62 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110107 figure 1 number of colours per chromatic group, (company a (1407 colours) vs. company b (1650 colours)) 4. classifying colours in our study we could identify how the repartition of colours in the fan decks of both companies into eight chromatic groups exposes in a first regard repetitive standards in colour classification. however, in the further course of our analysis, we could identify more subtle differences that constitute a clear divergence in the way of classifying colours. while we find a common general pattern of classification in both tools that we designate “standard pattern” for the sake of this analysis, the colour fields within each chromatic group are of different sizes. 4.1 case study of the chromatic group of yellows from figure 1 we pick as an example the chromatic group of yellows. in our visible spectrum, from shortest to longest wavelength, yellow (with a predominant wavelength of roughly 560–590 nm) is the colour between green and orange. when the three parameters of the colour differ (hue saturation lightness, known as hsl), the shades of yellow show a chromatic group particularly fluctuating, which makes it transition into another chromatic group. we identify this situation in the ncs colour space where the yellow family is represented with the letter -y but it is also possible to identify a letter-number combination -gy and -yr. this means the yellow is also part of the green (g) and red (r) colour family (hue). in our experience as colourist designer, usually, when it comes to choosing a yellow in a colour palette, this chromatic group is typically the smallest one offered by the industry, probably due to yellow not being a very dominating colour, so that even moderate variations rapidly introduce ambiguous colours that tend to transition into other chromatic groups, e.g. we find a certain ambivalence between yellow-oranges and yellowgreens. rearranging shades of yellow from different chromatic groups, in both colour palettes we find multiple alternative classifications of yellows (see fig. 2). in the ncs colour circle, company a proposes a chromatic group composed of a range from -g70y (70% of yellow and 30% of green) to -y20r (colour with 80% of yellow and 20% of red), i.e. we find yellow colours that fluctuate between greens, and pure yellows up to oranges. company b, on the contrary, expands the spectrum and proposes a group ranging from -g40y (40% of yellow and 60% of green) to -y20r (80% of yellow and 20% of red). this example shows a significant reinterpretation by the creative actor of what we know as the traditional colour circle (see fig. 3). n u m b e r o f c o lo u rs p e r fa m il y 300 200 100 0 p a s te ls w h it e s re d s re d s o ra n g e s o ra n g e s y e ll o w s y e ll o w s g re e n s g re e n s b lu e s b lu e s p u rp le s p u rp le s n e u tr a ls -e a rt h y n e u tr a ls company a company b industrial colour invention: a comparative analysis from the perspective of the colourist designer 63 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110107 figure 2 detail of chromatic group of yellows (company a (140 yellow colours) vs. company b (259 yellow colours)) figure 3 detail of chromatic group of yellows from company a vs company b situated inside the ncs colour space the total difference in terms of quantity of colours between the two palettes to the other one is less than 250 colours (~17%). in the group of yellows from the fan deck of company a, we find a hundred and forty (140, ~10% of the total number of colours) colours and two hundred fifty-nine (259, ~16 % of the total number of colours) colours in the fan deck of company b, a significant difference both in total and with respect to the size of the respective fan deck. the way of classifying the colours of the yellow group in the fan deck of company a, exposes a research of the colour quality in a quite specific and what appears to be deliberately limited way. yellow tones (~52%) show only subtle variations towards the orange (~34%) and the green shades (~14%) and the dominant colours in the group are light and pale colours (high lightness and medium and low saturation). this classification appears to work in the market and provides also a basis to rationalise the selection of a particular set of colour choices. the way colours are thought here is completely objective. its attributes seem to be based on cultural considerations (madden, t., et al., 2000). we feel a strong relation between the territory and the need to simplify the parameters of the palette to render it as a whole more accessible and to simplify its communication. considering the fan deck of company b, we notice that, as a colour expert from the field of applied arts, the colourist designer explores every possibility that helps to enrich and explore every shade of the colour group. this becomes evident not only by the classification of colours company a company b ncs digi tal atlas 1950 ncs natural color system ® ©, the ncs ® © notat ions and ncs ® © products are the property of the scandinavian colour institut e ab, st ockholm ©sci 2007. dependi ng on limitations in the printing t echnique, di fferences can aris e between the pri nted result of the ncs di gital at las and the nearest ncs colour sample. for technical reasons, variations between the moni tor and ncs ori ginal colour samples can also occu r. when communicating colou r, always refer to the ncs notation and an ncs original colour sample to be certain to get the best colour accurac y. natura l color system ®© the international language of colour c ommunication™ 42 10 05 20 30 40 50 60 70 80 90 20 05 02 10 20 30 40 50 80 90 70 60 v y =0.9 l v y =0.8 l v y =0.7 l v y =0.6 l v y =0.5 l v y =0.4 l v y =0.3 l v y =0.2 l v y =0.1 l -g50y -g -b -r -y c w s s 0550-g 10ys 0550-g 50y s 0520-g 50y s 0530-g 50y s 0540-g 50y s 1050-g 50y s 2050-g 50y s 2040-g 50y s 3040-g 50y s 3050-g 50y s 4040-g 50y s 4050-g 50y s 1030-g 50y s 2030-g 50y s 1020-g 50y s 2020-g 50y s 2010-g 50y s 7020-g 50y s 101 0g50y s 0510g50 y s 3020-g 50y s 3030-g 50y s 3010-g 50y s 8010-g 50y s 4020-g 50y s 4030-g 50y s 5020-g 50y s 5030-g 50y s 5040-g 50y s 5540-g 50y s 6020-g 50y s 6030-g 50y s 6530-g 50y s 4550-g 50y s 1040-g 50y s 7010-g 50y s 6010-g 50y s 5010-g 50y s 4010-g 50y s 2060-g 50y s 3060-g 50y s 3560-g 50y s 1070-g 50y s 1075-g 50y s 2070-g 50y s 3065-g 50y s 1060-g 50y s 0560-g 50y s 0565-g 50y s 4005-g 50y s 5005-g 50y s 6005-g 50y s 7005-g 50y s 8005-g 50y s 3005-g 50y s 2005g50 y s 0505g50 y s 100 5g50 y s 050 2g5 0y s 150 2g5 0y s 100 2g50y s 200 2g5 0y ncs digi tal atlas 1950 ncs natural color system ® ©, the ncs ® © notations and ncs ® © products are the property of the scandinavian colour institute ab, stockholm ©sci 2007. depending on limitations in the printing technique, di fferences can arise between the printed result of the ncs digital atlas and the nearest ncs colour sample. for technical reasons, variations between the monitor and ncs original colour samples can also occu r. when communicating colou r, always refer to the ncs notation and an ncs original colour sample to be certain to get the best colour a ccurac y. natural color system ®© the international language of colour communication™ 7 10 05 20 30 40 50 60 70 80 90 20 05 02 10 20 30 40 50 80 90 70 60 v y =0.9 l v y =0.8 l v y =0.7 l v y =0.6 l v y =0.5 l v y =0.4 l v y =0.3 l v y =0.2 l v y =0.1 l -y -g -b -r -y c w s s 1510y s 0515-y s 1015-y s 1515-y s 0 5 0 7 y s 0520-y s 0530y s 0540-y s 1070y s 0570y s 0580-y s 1080-y s 2070y s 1060y s 0560y s 2060y s 3060y s 1050y s 0550y s 2050y s 2040-y s 3040-y s 3050y s 4040-y s 4050y s 4550y s 1030y s 2030y s 1020-y s 2020-y s 2010y s 7020-y s 2005y s 1505y s 101 0-y s 0510y s 3020-y s 3030y s 3010y s 4020-y s 4030y s 5020-y s 5030y s 5040-ys 6020-y s 6030y s 0505y s 100 5 -y s 3560y s 1040-y s 050 2-y s 150 2-y s 100 2-y s 200 2-y s 250 2-y s 350 2-y s 650 2-y s 550 2-y s 450 2-y s 750 2-y s 850 2-y ncs digi tal atlas 1950 ncs natural color system ®©, the ncs ®© notations and ncs ®© products are the property of the scandinavian colour institute ab, s tockholm ©sci 2007. depending on lim itations in the printing technique, di fferences can arise between the printed result of the ncs digital atlas and the nearest ncs colour sample. for technical reasons, variations between the monitor and ncs original colour samples can also occu r. when com municating colou r, always refer to the ncs notation and an ncs original colour sample to be certain to get the best colour accurac y. natural color system ®© the international language of colour communication™ 8 10 05 20 30 40 50 60 70 80 90 20 05 02 10 20 30 40 50 80 90 70 60 v y =0.9 l v y =0.8 l v y =0.7 l v y =0.6 l v y =0.5 l v y =0.4 l v y =0.3 l v y =0.2 l v y =0.1 l -y10r -g -b -r -y c w s s 1510y 10r s 0 8 0 4 y 1 0 r s 0515y 10r s 1015y 10 r s 1515y 10 r s 0 9 0 7 y 1 0 r s 0520-y 10r s 0530-y 10r s 0540-y 10r s 1070-y 10r s 2070-y 10r s 1060-y 10r s 2060-y 10r s 3060-y 10r s 1050-y 10r s 0550-y 10r s 2050-y 10r s 2040-y 10r s 3040-y 10r s 3050-y 10r s 4040-y 10r s 4050-y 10r s 4055-y 1 0r s 1030-y 10r s 2030-y 10r s 1020-y 10r s 2020-y 10r s 2010-y 10r s 7020-y 10r s 2005-y 10r s 1505-y 10r s 10 10y 10r s 0510y 10r s 3020-y 10r s 3030-y 10r s 3010-y 10r s 8010-y 10r s 4020-y 10r s 4030-y 10r s 5020-y 10r s 5030-y 10r s 5040-y 10rs 6020-y 10r s 6030-y 10r s 0505-y 10r s 10 05y10 r s 1040-y 10r s 7010-y 10r s 6010-y 10r s 5010-y 10r s 4010-y 10r s 0570-y 10r s 0580-y 10r s 0560-y 10r s 1080-y 10r ncs digi tal atlas 1950 ncs natural color system ®©, the ncs ®© notations and ncs ®© products are the property of the scandinavian colour institute ab, s tockholm ©sci 2007. depending on lim itations in the printing technique, di fferences can arise between the printed result of the ncs digital atlas and the nearest ncs colour sample. for technical reasons, variations between the monitor and ncs original colour samples can also occu r. when com municating colou r, always refer to the ncs notation and an ncs original colour sample to be certain to get the best colour accurac y. natural color system ®© the international language of colour communication™ 9 ncs digital atlas 1950 ncs natural color system ®©, the ncs ®© notations and ncs ®© products are the property of the scandinavian colour institute ab, stockholm ©sci 2007. natural color system ®© the international language of colour communication™ 6 c = 00 c = 02 -b -r-g -y g50y b50g r50b y50r s 0502 v y 8 7 = 0 .9 5 l v y = 0 .9 l 7 6 v y = 0 .8 5 l 6 7 v y = 0 .8 l 5 9 v y = 0 .7 5 l 5 2 v y = 0 .7 l 4 6 v y = 0 .6 5 l 4 0 v y = 0 .6 l 3 5 v y = 0 .5 5 l 3 0 v y = 0 .5 l 2 6 v = 0 .4 5 y l 2 3 v y = 0 .4 l 1 9 v y = 0 .3 5 l 1 6 v y = 0 .3 l 1 3 v y = 0 .2 5 l 1 1 v y = 0 .2 l 8 v y= 0 .1 5 l 6 v y = 0 .1 l 4 s 1002 s 1502 s 2002 s 2502 s 3502 s 4502 s 5502 s 6502 s 7502 s 8502 -y -y -y50r -r -r -r50b -b50g -g -g -g50y -n -b -b s 0 5 0 2 -b 5 0 g s 0 5 0 2 -g 5 0 y s 1 0 0 2 -g 5 0 y s 1 5 0 2 -g 5 0 y s 0 5 0 2 -b s 1 0 0 2 -b s 1 5 0 2 -b s 2 5 0 2 -b s 3 5 0 2 -b s 4 5 0 2 -b s 5 5 0 2 -b s 6 5 0 2 -b s 8 5 0 2 -b s 0 5 0 2 -r s 0 5 0 2 -y s 1 0 0 2 -y s 1 5 0 2 -y s 2 5 0 2 -y s 3 5 0 2 -y s 4 5 0 2 -y s 5 5 0 2 -y s 6 5 0 2 -y s 8 5 0 2 -y s 1 0 0 2 -r s 1 5 0 2 -r s 2 5 0 2 -r s 3 5 0 2 -r s 4 5 0 2 -r s 5 5 0 2 -r s 6 5 0 2 -r s 8 5 0 2 -r s 1 5 0 2 -g s 2 5 0 2 -g s 3 5 0 2 -g s 4 5 0 2 -g s 5 5 0 2 -g s 6 5 0 2 -g s 7 5 0 2 -g s 8 5 0 2 -g s 1 0 0 2 -g s 0 5 0 2 -g s 1 0 0 2 -b 5 0 g s 1 5 0 2 -b 5 0 g s 1 5 0 2 -r 5 0 b s 1 5 0 2 -y 5 0 r s 1 0 0 2 -y 5 0 r s 0 5 0 2 -y 5 0 r s 1 0 0 2 -r 5 0 b s 0 5 0 2 -r 5 0 b s 0500-n s 1000-n s 1500-n s 2000-n s 2500-n s 3500-n s 3000-n s 4500-n s 4000-n s 5500-n s 5000-n s 6500-n s 6000-n s 7500-n s 7000-n s 8500-n s 8000-n s 9000-n c=02 -n -y -y50r -r -r50b -b -b50g -g -g50y c=00 s 2 0 0 2 -y 5 0 r s 2 0 0 2 -r 5 0 b s 2 0 0 2 -b 5 0 g s 2 0 0 2 -g 5 0 y s 2 0 0 2 -y s 2 0 0 2 -r s 2 0 0 2 -b s 2 0 0 2 -g v y = 0 .9 7 l 9 1 s 0300-n s 7 5 0 2 -b s 7 5 0 2 -r s 7 5 0 2 -y depending on limitations in the printing technique, di fferences can arise between the printed result of the ncs digital atlas and the nearest ncs colour sample. for technical reasons, variations between the monitor and ncs original colour samples can also occu r. when communicating colou r, always refer to the ncs notation and an ncs original colour sample to be certain to ge t the best colour accurac y. ncs digi tal atlas 1950 ncs natural color system ®© , the ncs ®© notations and ncs ®© products are the property of the scandinavian colour institute ab, stockholm ©sci 2007. natural color system ®© the international language of colour communication™ 5 -b -g -y -r -b10g -b20g -b30g -b40g -b50g -b60g -b70g -b80g -b90g -g10y -g20y -g30y -g40y -g50y -g60y -g70y -g80y -g90y -y10r -y20r -y30r -y40r -y50r -y60r -y70r -y80r -y90r -r10b -r20b -r30b -r40b -r50b -r60b -r70b -r80b -r90b s 1 5 6 5 b s 1080r s 1575-r10 b s 2060 -r20b s 2060 -r30 b s 20 60 -r40b s 3055-r 50b s 3 5 5 5 -r60 b s 3 0 6 0 -r7 0 b s 2 5 6 5 -r 8 0 b s 2 0 6 5 -r 9 0 b s 0 5 8 0 -y s 0 5 8 0 -y 1 0 r s 0 5 8 0 -y 2 0 r s 0 5 8 0 -y 3 0 r s 0 5 80 -y 4 0 r s 0 58 0y 50 r s 05 80 -y6 0r s 0 58 0 y7 0r s 05 80 -y80 r s 058 0 -y90 r s 1565g s 1070 -g10y s 05 70-g20 y s 057 0 -g3 0y s 0570-g 40y s 0 565-g 50y s 0 5 70 -g 6 0 y s 0 5 7 0 -g 7 0 y s 0 5 7 0 -g 8 0 y s 0 5 7 5 g 9 0 y s 2 0 5 5 -b 1 0 g s 2 5 5 5 -b 2 0 g s 2 5 5 5 -b 3 0 g s 2 55 5 -b 4 0 g s 2 06 0 -b 5 0g s 25 55 -b 60 g s 2 06 0 b7 0 g s 25 55b80 g s 206 0b90 g depending on limitations in the printing technique, di fferences can ari se between the printed result of the ncs digital atlas and the nearest ncs colour sample. for technical reasons, variations between the monitor and ncs original colour samples can also occu r. when communicating colou r, always refer to the ncs notation and an ncs original colour sample to be certain to get the best colour accurac y. chromatic group no 4 -y, -y10r, -y20r -g50y, -g60y, -g70y, -g80y, -g90y ncs digi tal atlas 1950 ncs natural color system ® © , t he ncs ® © notat ions and ncs ® © products are the property of the scandinavian colour institute ab, st ockholm ©sci 2007. dependi ng on limitations in the printing t echnique, di fferences can aris e between the pri nted result of the ncs di gital atlas and the nearest ncs colour sample. for technical reasons, variations between the moni tor and ncs ori ginal colour samples can also occu r. when communicating colou r, always refer to t he ncs notation and an ncs original colour sample to be certain to get the best colour accurac y. natura l color system ®© the international language of colour c ommunication™ 43 10 05 20 30 40 50 60 70 80 90 20 05 02 10 20 30 40 50 80 90 70 60 v y =0.9 l v y =0.8 l v y =0.7 l v y =0.6 l v y =0.5 l v y =0.4 l v y =0.3 l v y =0.2 l v y =0.1 l -g60y -g -b -r -y c w s s 0515g60 y s 1015g60 y s 1515g60 y s 0520-g 60y s 0530-g 60y s 0540-g 60y s 1060-g 60y s 0560-g 60y s 2060-g 60y s 1070-g 60y s 0570-g 60y s 2070-g 60y s 1075-g 60y s 0575-g 60y s 3060-g 40y s 1050-g 60y s 0550-g 60y s 2050-g 60y s 2040-g 60y s 3040-g 60y s 3050-g 60y s 4040-g 60y s 4050-g 60y s 1030-g 60y s 2030-g 60y s 1020-g 60y s 2020-g 60y s 3020-g 60y s 3010-g 60y s 3030-g 60y s 5040-g 60y s 5540-g 60y s 3560-g 60y s 3065-g 60y s 4550-g 60y s 1040-g 60y s 2005-g 60y s 101 0g60 y s 0510g60 y s 0505-g 60y s 100 5g60 y s 1510g60 y s 2010g60 y s 0 8 0 4 g 6 0 y s 0 9 0 7 g 6 0 y ncs digi tal atlas 1950 ncs natural color system ® © , the ncs ® © notat ions and ncs ® © products are the property of the scandinavian colour institut e ab, st ockholm ©sci 2007. dependi ng on limitations in the printing t echnique, di fferences can aris e between the pri nted result of the ncs di gital atlas and the nearest ncs colour sample. for technical reasons, variations between the moni tor and ncs ori ginal colour samples can also occu r. when communicating colou r, always refer to t he ncs notation and an ncs original colour sample to be certain to get the best colour accurac y. natura l color system ®© the international language of colour c ommunication™ 44 10 05 20 30 40 50 60 70 80 90 20 05 02 10 20 30 40 50 80 90 70 60 v y =0.9 l v y =0.8 l v y =0.7 l v y =0.6 l v y =0.5 l v y =0.4 l v y =0.3 l v y =0.2 l v y =0.1 l -g70y -g -b -r -y c w s s 0550-g 10ys 0550-g 70y s 0520-g 70y s 0530-g 70y s 0540-g 70y s 1050-g 70y s 2050-g 70y s 2040-g 70y s 3040-g 70y s 3050-g 70y s 4040-g 70y s 4050-g 70y s 1030-g 70y s 2030-g 70y s 1020-g 70y s 2020-g 70y s 2010-g 70y s 7020-g 70y s 101 0g70 y s 0510g70y s 2005-g 70y s 100 5g70 y s 0505g70y s 3020-g 70y s 3030-g 70y s 3010-g 70y s 8010-g 70y s 4020-g 70y s 4030-g 70y s 5020-g 70y s 5030-g 70y s 5040-g 70y s 5540-g 70y s 6020-g 70y s 6030-g 70y s 4550-g 70y s 1040-g 70y s 7010-g 70y s 6010-g 70y s 5010-g 70y s 2060-g 70y s 3060-g 70y s 3560-g 70y s 1070-g 70y s 0570-g 70y s 0575-g 70y s 1075-g 70y s 2070-g 70y s 1060-g 70y s 0560-g 70y s 4010-g 70y ncs digi tal atlas 1950 ncs natural color system ® ©, t he ncs ® © notat ions and ncs ® © products are the property of the scandinavian colour institute ab, st ockholm ©sci 2007. dependi ng on limitations in the printing technique, di fferences can arise between the pri nted result of the ncs di gital atlas and the nearest ncs colour sample. for techni cal reasons, variations between the moni tor and ncs ori ginal colour sampl es can also occu r. when communicating colou r, always refer to the ncs notation and an ncs origi nal colour sample to be certain to get the best colour accurac y. natura l color system ®© the international language of colour c ommunication™ 4 5 05 02 10 20 30 40 50 80 90 70 60 v y =0.9 l v y =0.8 l v y =0.7 l v y =0.6 l v y =0.5 l v y =0.4 l v y =0.3 l v y =0.2 l v y =0.1 l -g80y -g -b -r -y c w s 10 05 20 30 40 50 60 70 80 90 s 2005-g 80y s 1505-g 80y s 101 0g80 y s 0510g80 y s 0515g80 y s 1015g80 y s 1515g80 y s 1510g80 y s 2010g80 y s 3010g80 y s 0520-g 80y s 0530-g 80y s 0540-g 80y s 1060-g 80y s 0560-g 80y s 2060-g 80y s 1070-g 80y s 0570-g 80y s 2070-g 80y s 1075-g 80y s 3060-g 80y s 1050-g 80y s 0550-g 80y s 2050-g 80y s 2040-g 80y s 3040-g 80y s 3050-g 80y s 4040-g 80y s 4050-g 80y s 1030-g 80y s 2030-g 80y s 1020-g 80y s 2020-g 80y s 3020-g 80y s 3030-g 80y s 5040-g 80y s 1040-g 80y s 0 6 0 3 g 8 0 y s 0 5 0 7 g 8 0 y s 0505-g 80y s 100 5g80 y s 4005-g 80y s 5005-g 80y s 6005-g 80y s 7005-g 80y s 8005-g 80y s 8505-g 80y s 3005-g 80y ncs digi tal atlas 1950 ncs natural color system ® © , the ncs ® © notat ions and ncs ® © products are the property of the scandinavian colour institute ab, st ockholm ©sci 2007. dependi ng on limitations in the printing t echnique, di fferences can aris e between the pri nted result of the ncs di gital atlas and the nearest ncs colour sample. for technical reasons, variations between the moni tor and ncs ori ginal colour samples can also occu r. when communicating colou r, always refer to t he ncs notation and an ncs original colour sample to be certain to get the best colour accurac y. natura l color system ®© the international language of colour c ommunication™ 46 10 05 20 3 0 40 50 60 70 80 90 20 05 02 10 20 30 40 50 80 90 70 60 v y =0.9 l v y =0.8 l v y =0.7 l v y =0.6 l v y =0.5 l v y =0.4 l v y =0.3 l v y =0.2 l v y =0.1 l -g90y -g -b -r -y c w s s 0515g90y s 1015g90 y s 1515g90 y s 0520-g 90y s 0530-g 90y s 0540-g 90y s 1060-g 90y s 0560-g 90y s 2060-g 90y s 1070-g 90y s 0570-g 90y s 2070-g 90y s 1075-g 90y s 0575-g 90y s 3060-g 90y s 1050-g 90y s 0550-g 90y s 2050-g 90y s 2040-g 90y s 3040-g 90y s 3050-g 90y s 4040-g 90y s 4050-g 90y s 1030-g 90y s 2030-g 90y s 1020-g 90y s 2020-g 90y s 3020-g 90y s 3010-g 90y s 3030-g 90y s 5040-g 90y s 1040-g 90y s 2005-g 90y s 1505-g 90y s 101 0g90y s 0510g90 y s 0505-g 90y s 100 5g90y s 1510g90 y s 2010g90 y s 0 8 0 4 g 9 0 y s 0 9 0 7 g 9 0 y s 7020-g 90y s 8010-g 90y s 4020-g 90y s 4030-g 90y s 5020-g 90y s 5030-g 90y s 6020-g 90y s 6030-g 90ys 7010-g 90y s 6010-g 90y s 5010-g 90y s 4010-g 90y the images used for this analysis are the property of ncs colour system ® ©. yellows company a yellows company b industrial colour invention: a comparative analysis from the perspective of the colourist designer 64 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110107 according to their standard parameters (hsl), but also by the visible impact of artistic sensitivity and imagination. yellow tones (~43%) in this group are more varied, alternating yellow greenish tones (~46%) and yellow orange tones (~11%), showing and further exploring the characteristic vivid, dynamic influence of yellow. however, colour as an objective entity, conceived to be part of an industrial system, plays an important role in the act of classifying colours from an artistic expertise. inside a normative sector, the sensible perspective of the colourist designer is nourished by a multitude of stories, dreams and experiences, always keeping in mind that the focus in an industrial context lies almost always on proposing a common model for everyone to render colour communication easier and neutral. the case study of the chromatic group of yellows exposes two of so many different existing possibilities of seeing and associating colours. this case study, however, is only a first step and is followed by an analysis of the process of naming and codifying every colour. 5. naming colours for the two analysed colour palettes, both companies have developed their own colour classification systems instead of adopting an existing standard proposed by companies specialised in the design of colour communication tools. the relationship between colours and language was important for both creative processes. this relationship has been questioned from different domains of research. for example, the anthropological method, basic colour terms (1969), where the authors brent berlin and paul kay (berlin, b., kay, p., 1999) state that there are 11 fundamental colour terms that exist in every culture: white, black, red, green, yellow, blue, brown, purple, pink, orange and grey. this model, formalised solely based on language, has generated a controversial debate in the colour research community. in our particular case, comparing the chromatic groups identified in our study with the eleven “basic colour terms”, we see a great deal of agreement, but also differences, providing an example of how a specific creative and cultural environment generates a specific narrative, expressed by a specific set of colour terms. the direction we have identified in the corpus of the two colour palettes analysed from a linguistic point of view (berlin, b., kay, p., 1999) reduces the 11 basic colour terms in the fan deck a to six basic colour terms (reds, oranges, yellows, greens, blues, purples) and in the second one (fan deck b) to seven basic colour terms (whites, reds, oranges, yellows, greens, blues, purples) (see fig.4). however, we could easily recognise the 11 basic colour terms inside every chromatic group of both fan decks. is this configuration of having only 8 chromatic groups specific to the terrain of the paint and coatings industry? would it be possible for the industry to create its own ‘universal’ classification without taking into account the culture of the consumer? figure 4 number of colours per chromatic group based on basic colour terms. n u m b e r o f c o lo u rs p e r fa m il y 300 200 100 0 p a s te ls w h it e s re d s re d s g re e n s g re e n s y e ll o w s y e ll o w s b ro w n s b ro w n s b lu e s b lu e s p u rp le s p u rp le s g ra y s g ra y s o ra n g e s o ra n g e s p in k s p in k s b la c k s b la c k s company a company b 65 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110107 company a (latin america) marketing expertise company b (europe) colour design expertise rayo de sol am005 – t 41n – 48 – 100t 01a5 oro azteca am006 – d 41n – 65 – 100d 01a6 hojas de oro am007 – d 45n – 75 – 100d 01a7 table 2 example of naming colours in the yellow group returning to our case study of the group of yellows, studying the colour codification helped us as well to identify how the same colour assumes different identities in different terrains. in tab. 2 we show three examples of very similar colours (mapped to the ncs) and their respective codes in both fan decks. for the company a, proposing three different codifications for each colour, answering to three different user groups, shows the diversity of the tool in terms of fulfilling its primary function. a strong, threefold colour identity is build, providing a guide to the imagination of the user. as such, it appears that colour is thought of as rather objective entity, even if a descriptive code is proposed, introducing poetic aspects. for company b, we are confronted with a numerical code system, structuring the tool in a rigorous, however easily accessible manner. colour is approached from a rather subjective perspective. we make the hypothesis that omitting a descriptive code implies putting fewer constraints on the imagination of the user of the tool. this is directly related to an aspect of great interest in the field of poietics, the possibility to free up the imaginary by artistic means in an industrial context, in contrast to marketing-centered approaches and their inherent tendency to strongly constrain the imaginary (lecerf, 2014). finally, questioning the organisation of colour in lexical terms involves thinking of the existence of multiple ways of conceiving colour. naming colours in the industry implies a reflection between linguistic norms and colour sensitivity so it can be applied to form chromatic groups. so, the question that remains open in relation to our own expertise is: can we propose new meaningful ways of classifying and naming colours that open up the imaginary? 6. discussion and further research the paint and coatings industry, according to the results of our analysis, offers a promising field of investigation for the colourist designer questioning creative processes in the invention of colour. based on the framework of action research in arts and adopting creative methods from the field of poietics, even if the results of this study indicates that further insights (such as comparing in a more measurable manner the speed or duration spent on determining each chromatic group of each fan deck which could help us to identify possible mistakes or miscommunications during the creative processes), could be gained by closer in-situ examination of the creative process of each actor. analysing two different sets of expertise and the colour communication tools resulting from their application has allowed us to gain a deeper understanding of the role our field of research as colourist designer can play in this context. we identified distinctly different creative approaches of the involved actors, intimately linked to their expertise and artistic priorities. without the necessity of judging the quality of a particular tool our work clearly exposes how the artistic sensibility of each actor permeates and becomes apparent in the details of a tool designed in both cases primarily for purely commercial purposes, widening our perspective as colourist designers. based on this analysis and our ongoing exchange with key actors, we can state that our study about colour classification and nomination inside the industry is a first industrial colour invention: a comparative analysis from the perspective of the colourist designer 66 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110107 approach towards a new definition of the meaning of a chromatic group in an industrial context today. as a further extension of our work, it would also be interesting to bring together the colour charts that both companies have produced over the last two decades. the gathering of these tools could allow us to identify the colours belonging to each chromatic group to be able to build a chromatic circle specific to the context of the decorative painting industry in the 21st century. the resulting circle could be used to make comparisons with the chromatic circles proposed in the past, but it could above all become a representative object not only of the considered industries but of the chromatic identities of the corresponding territories. according to a study by borstein (1973), in south america, 9 of the 12 indian cultures considered used one word for both green and blue. it would be interesting to perform a deeper analysis of the way in which company a develops colour names and codes, considering that with exception of the group of neutral-earthy colours, the greens are the largest group, covering colorimetric values from two different colour families according to ncs. furthermore, important structural questions remain open when it comes to colour invention in the industry. does more potential lie in proposing new methods for the creative individual, playing such a dominant role today? or does it lie in creating new models of interaction between key actors providing different sets of expertise to enrich and widen the diversity of the artistic process? these questions, among others, will guide our future research efforts. 7. conflict of interest declaration the author declares that nothing has affected her objectivity or independence in the production of this work. the author has no financial interest in the people, topics or companies mentioned this article. so, no conflict of interest exists. 8. funding source declaration the research was partially supported by the institut des amériques and the university toulouse jean jaurès (france). 9. acknowledgment the author would like to thank both companies who provided the invaluable and useful information that forms the basis of this research. 10. short biography of the author(s) lina perdomo is a colourist designer and phd candidate at the university toulouse jean jaurès in toulouse, france. her research is focused on creative colour development processes in an industrial context from the perspective of the colourist designer applying the approach of poietics and action research. notes [1] three main groups of customers have been identified: 1) the one who is afraid of too much colour and who therefore prefers to stay in the areas of light colours (pastels), 2) the one who has a favourite colour, so he must be guided in his specific chromatic group and finally 3) the one who likes colours but does not like taking risks so he prefers neutral-earthy colours. references berlin, b., kay, p. (1999) basic colour terms, their universality and evolution. stanford: csli publications. caumon, c., houssard, f., lecerf, g., ling, l., ollier, x. (2016) recherche action par la création artistique et design. saint-denis: connaissances et savoirs, pp. 21. copans, j., (2011) l’enquête ethnologique de terrain: l’enquête et ses méthodes. 3e édition, paris : armand colin ladnytska, o., tsurkan, m., (2015) linguistic aspects of colour in ian mcewan’s ‘atonement’. science and education a new dimension. philology, iii(16), issue: 70 lecerf, g., (2014) le coloris comme expérience poétique. paris: l’harmattan, pp. 71-72. liu, m., (1997) fondements et pratiques de la recherche-action, paris : éditions l’harmattan madden, t., hewett, k., roth, m., (2000) managing images in different cultures : a cross-national study of color meanings and preferences. journal of international marketing : vol 8, no 4, pp. 90 -107 passeron, r., (1989) pour une philosophie de la création. paris : klincksieck, pp. 21, 54. passeron, r., (1996) la naissance d’icare. éléments de poïétique générale. cachan (val de marne) : ae2cg éditions pogacar, v., (2012) periodic colour model. journal of the international colour association : 9, 5-19 cultura e scienza del colore color culture and science cultura e scienza del colore color culture and science | special issue on food color | 05 | 2016 49 issn 2384-9568 a look into cross-modal associations between taste, color and music 1paul chambers p.r. chambers@edu.salford.ac.uk 1marianne patera m.patera@salford.ac.uk 1trevor cox t.j.cox@salford.ac.uk 1computing, science and engineering, university of salford, uk abstract this paper explores how color and sound can alter taste perception and in particular whether there are any cross-modal associations between these three stimuli. it questions how information from stimuli outside the realms of gastronomy is combined in the brain to influence a person’s taste perception. this study tested how colored ambient lighting and piano music can influence people’s sweet taste; this is the first experiment to study the associations between all three stimuli. the experiment provided some interesting results; most significantly it was found that the color red and high pitch piano music both have a significant impact upon a person’s enjoyment of sweet taste. citation: chambers p., patera m., cox t. (2016) ‘a look into cross-modal associations between taste, color and music’, cultura e scienza del colore color culture and science journal, special issue on food and colour, 05, pp. 49-54, doi: 10.23738/ccsj.i52016.06 received 08 september 2015; revised 10 january 2016; accepted 08 february 2016 cultura e scienza del colore color culture and science | special issue on food color | 05 | 2016 | 49 54 50 chambers p. et al. issn 2384-9568 doi: 10.23738/ccsj.i52016.06 1. introduction the study sits firmly inside the realms of perceptual psychology and explores the theories of cross-modal associations (multisensory interactions) and aims to further understand how color and sound can influence non-synaesthetic people’s taste when consuming something sweet. it is known that color and sound can alter a person’s mood and feelings, therefore this investigation reviewed similar experiments conducted in controlled laboratory conditions as well as real world applications. the research attempts to show whether the combination of certain sounds/music and colored ambient lighting can have an impact on a person’s taste, even though the senses involved in perceiving these stimuli are not linked in any way. since this study investigated whether and to what extent taste is affected by color and pitch perception, we reviewed (in different sections) the literature on interactions between taste and color as well as between taste and auditory cues. as yet there has not been a study involving these three stimuli combined in non-synaesthetic people. 1.1 color and taste color can warn of danger and convey mood hence it is incredibly important in relation to food and cooking. color is important whilst cooking and is often the first point of sensory contact used to decide on taste opinions [1, 2]. colors and their meanings are built into a person’s culture and are therefore situational and dependent on learnt associations, which can be subject to change [3]. zampini et al. [4] created an experiment that taste tested different colored flavored and unflavored liquids and found that the participants’ flavor identification response was influenced by the color of the liquid. this shows that the visual information presented to them superseded any awareness or learnt associations they had about the particular color and flavor combination. in 2009, oberfeld et al. [5] conducted a tasting experiment where participants judged wine in different ambient lighting conditions. blue was found to be the most pleasant overall, which is in agreement with the average color preferences in western adults [6]. interestingly, in a red illuminated room, the 260 participants perceived the wine to be 50% sweeter than under the blue, green or white lights. these colors are often used in visual perception experiments and that is why they were chosen for the study presented in this paper. an explanation of these results could be that the differences in color affected the participants’ moods (subconsciously), which could have altered their taste as red is commonly associated with the sweet taste [7]. the participants’ mood and current state is a very important aspect in perception studies [8]. a taste testing experiment which involved administering randomly ordered, sucrose solutions of various sweetness (in a blind experiment situation), demonstrated that participants could successfully identify changes in sweetness in clear liquids, yet they could not identify a change when the liquid was red [9]. when only the color had been changed and not the sweetness, they wrongly noticed changes in sweetness when there were none. this is an adaptation of the “stroop effect” [10] and clearly shows that color can directly alter flavor perception. 1.2 sound and taste music and taste have been intrinsically linked for centuries; zarlino, an important musical theorist of the 16th century, described the minor consonances as “sweet” and “soft” [11]. music and taste descriptive words are often used together subconsciously and can affect a person’s decision making. the fat duck restaurant in bray, england serves a dish of seafood with an ipod hidden in a seashell; the ipod plays sounds of the sea through headphones. this sound apparently makes the flavors in the dish stronger and more appealing [12]. crisinel and spence [13] created an experiment where 12 different flavors, representing the five basic tastes, were presented to participants while a melody from a number of different instruments was simultaneously played; the audio samples increased in pitch from c2 to c6 (western scale). they found that the piano was the most pleasant and brass instruments the most unpleasant across all the flavors. the piano instrument was generally preferred in experiments involving the sweet taste and sound. another experiment involved taste testing different chocolates (milk, marzipan & dark) while listening to music played by varying instruments (piano, strings, woodwinds and brass) in various pitches (c2-c6 western scale) [14]. the piano instrument was most closely linked to high scores of pleasantness but a significant association between chocolate and pitch could not be established, yet a significant relationship between sweetness, pleasantness and the piano instrument was established. in contrast to other studies, simner et al. [15] matched the sweet taste to low pitch. however, the high pitch stimulus was described as ‘unpleasant’ by the participants, whilst the low pitch sound was a pleasant vowel noise. ‘hedonic matching’ is where two separate dimensions of a scale correspond, because both ends of the scale are either pleasant or unpleasant [15]. cultura e scienza del colore color culture and science | special issue on food color | 05 | 2016 | 49 54 51a look into cross-modal associations between taste, color and music issn 2384-9568 therefore the experiment generated correlated results because the sweet taste and low pitch were both perceived as being pleasant, which shows that sweetness is not necessarily linked to high pitch. it has been inferred that the sweet taste has a direct link to the feeling of happiness and pleasantness [14]. 2. hypothesis it was expected that color will have an impact on taste perception, as it is a strong modifier of taste as shown in previous studies. it was also hypothesised that red would be associated more with the sweet taste. hypothesis 1: higher pitches and warmer colors have a positive impact on likings of the sweet taste stimulus. hypothesis 2: music and color have a correlation to each other in affecting a person’s sweet taste perception. 3. experiment design the aim of the research was to gain a better understanding of how sound and color together can affect taste and in particular which colors and sounds, and in what combination can affect taste. this involved a deceptive administration experiment [16] as each person was told they will be handed ‘different samples’ of a sweetened clear liquid yet in reality all the samples were the same. the participants received 24 solutions made of sucrose solidified in water. the participants drunk the stimulus 24 times during the experiment under different colored ambient lighting (red, blue, green and white), while listening to three chords, at 2 different pitches. the experiment followed a repeated measures design and so every participant experienced all conditions. all the stimuli were delivered to the participant in a random and controlled manner. similar to zampini’s et al. [4] experiment, each participant faced a computer screen and wore noise cancelling headphones in a darkened room and remained facing forward throughout the study. once the oral instruction had been given, further instructions were provided on the screen; the experimenter left the room and the samples were passed through a hatch. this method was applied in order to reduce any external distractions, increase the engagement of the participants as well as remove the human element as much as possible in order to lessen the ‘observer effect’ [17]. each participant was asked the question “how sweet was that taste?” after consuming a sample drink (this was measured on a rating scale from 0 = not sweet to 10 = incredibly sweet). 3.1 taste stimulus the taste stimulus was delivered in clear plastic shot glasses so the light from the computer screen could illuminate through the liquid and give a greater amount of color influence. zampini et al. [4] used colored liquid, whereas in this experiment the color of the lighting and not the liquid color itself was tested. after the pilot trials it was decided that 80g of sugar solidified in 1l of water at room temperature (20 ± 2 ºc) gave varied results along the 10-point scale and was always deemed ‘pleasant’, even towards the end of the experiment. the volume of the liquid was set to 15ml as this seemed an adequate amount to properly taste the stimulus. the participants were asked to rinse their mouth with water before starting the test. 3.2 color stimulus this study used similar colors to oberfeld’s et al. [5] experiment as they have been proven to show cross-modal associations. red, blue and green represent a good proportion of the primary color wheel whereas white was used to simulate neutral lighting. the white light condition served as the control condition and is not expected to create a positive or negative correlation. the exact color attributes are shown in table 1. these parameters were chosen in order to give the most uniform lightness level across all colors. these were created as images which covered the whole computer screen that illuminated the room. the participants in hasenbeck’s et al. [18] experiment were shown pictures of bell peppers at varying luminance levels, and were asked to rate how appealing they were. yellow and blue peppers were enjoyed most at higher luminance levels and were enjoyed significantly less at lower levels. for this reason the luminance levels of all colors in this experiment remained consistent. the luminance level was measured at a distance of 0.5m for each color, which all fell between 150 and 200 lux, and the initial color temperature of the room was within the desired restaurant color temperature of 4,000k [19]. 3.3 sound stimulus the variables chosen for this test were note and pitch as they have been used as variables in previous perception experiments. pitch, in particular, has been proven to have a significant impact on cross-modal associations [20]. it was a b l blue 28.9 -95.4 71.8 green -65.9 68.6 72.3 red 78.5 54.9 71.2 white -1.6 -0.1 96 table 1 cielab color parameters cultura e scienza del colore color culture and science | special issue on food color | 05 | 2016 | 49 54 52 chambers p. et al. issn 2384-9568 doi: 10.23738/ccsj.i52016.06 decided to use a chord, rather than a melody, song or tone. using a melody could introduce personal preferences whereas using a single tone may not have been interesting enough or contain enough harmonic content to influence a person’s taste perception. a chord was chosen because they are not as complex as harmonies or melodies and are also easier to define and analyse in a quantitative manner. all of the notes used were in the major scale (chords c, d & e in major). these chords were chosen as they were in the middle of the chosen octaves, which started at c2 and went up to c4. the low pitch (c2) and high pitch (c4) variants were chosen respectively because they had featured in other studies [13, 14]. each audio sample was created using a piano emulation synthesizer; the samples had no effects or equalisation added. they had all exactly the same volume (60-70db), length (8s), velocity and envelope characteristics. 4. results the 19 participants who took part in this test were chosen at random and their ages varied between 18-35. none of the subjects reported being color blind or having hearing problems. the dependent variable in this experiment was the sweet taste perception of the 24 sucrose solutions which was measured on a rating scale from 0-10. the independent variables were the color (4 levels – red, green, blue and white), the pitch (2 levels – high and low) and the note (3 levels – c, d and e). the chosen method of analysis was a repeated measures withinsubject factor anova. a three-way anova was performed for all three factors (color, pitch and note) including all possible interactions. the significance value used in the analysis was p < 0.05. it was found that none of the factors violated mauchley’s test of sphericity, except for the note against color factor, which had a p value of 0.006; in this exception the greenhousegeisser correction was used, which did not exceed 0.05. figure 1 shows the total sweetness rating of the sucrose drink for each color, note and pitch for all participants. this graph exhibits that the sweetness rating of the stimulus increased when the higher pitched audio was used. the low pitch mean total was 5.15 and the high pitch mean total was 6.8. a 27% (+1.675) increase in sweetness level demonstrates that pitch has an effect on taste. pitch had a significant effect on taste perception (p<0.0005, f = (1, 18) = 34.086). a partial eta squared effect size calculation returned η2=0.545, which is seen as a large effect size. it was therefore demonstrated that the participants experienced an increase in perceived sweetness whilst listening to the higher pitched piano sample, as opposed to the low pitched piano sample. the anova found that the notes used in this experiment (c, d and e) did not have a significant effect on taste perception (f = (2, 36) = 0.249, p= 0.781). color was found to have a significant effect on taste perception with a significance value of p = 0.0005 (f= (3, 54) = 7.292), which also returned a partial eta squared effect size of η2= 0.757. figure 2 shows the total mean sweetness level scores for each color (full scale range 0-10). green and red resulted in the same mean score and so they occupy the high scoring group, whereas white (control condition) was lowest, with blue also occupying the low scoring group. a significant difference can be seen between the high group and the low group, in particular between red/green and blue. on average red and green provided the highest positive crossmodal association with the sweet taste stimulus (the sweet taste perception increased when these colors were used). however, none of the interactions between the three variables were significant (all p > 0.05). this means that no new cross-modal links between multisensory stimuli and taste perception could be established in this experiment. 5. discussion the results showed that high pitch piano music generated a clear increase in sweetness ratings which is in agreement with our hypothesis and results from previous studies [13, 21]. the use of taste words as metaphors has been happening for centuries (e.g. sweet melody), it is however unclear as to whether people match sweet tastes to what they perceive as sweet music, based on the correlation between the two ends of the positive or negative aspect of the medium (hedonic matching) or whether the two are matched together because of the “high-low” terminology used between the two modalities (semantic matching). this could be an area of further research, to try and prove which process humans use when creating subconscious crossmodal associations. the different musical chords used in the experiment did not show to have a significant effect on taste perception. this was not a surprising outcome, as different chords were mainly used to maintain the subjects’ engagement. furthermore, the small change in chord might have been masked by the large changes in pitch and/or the sample size was not big enough to exhibit a trend in the data. color showed a statistically significant effect on sweet taste perception, with red and green being linked to higher sweetness scores than blue or white. a probable reason why red and green influenced the level of perceived sweetness is that these colors were generally linked to higher cultura e scienza del colore color culture and science | special issue on food color | 05 | 2016 | 49 54 53a look into cross-modal associations between taste, color and music issn 2384-9568 sweetness than blue or white, as they are more commonly associated with sweets and sugar. the low scoring result of blue and the high scoring result of red and green demonstrate the notion of cross-modal interaction in this experiment. they show that the results were not based on general color preferences but were influenced by the experiment conditions. the process of ‘hedonic matching’ could also relate to the color variable as the words used to describe both high sweetness and high pitch, can also be used to describe colors that are higher in tonal range (lighter) and higher in color temperature (warmer), like red is as opposed to blue. this could be another theory that strengthens the synaesthetic bonds between senses since often similar describing words are used or borrowed to describe perceptions outside of that particular sense. nevertheless, this experiment has not found new significant associations between colors, piano chords and sweet taste perception. a possible reason for not reaching any correlations between all three stimuli could be that there is simply no correlation to be made. perhaps the sample size was not large enough to exhibit a trend in the data however previous experiments have managed to find associations between the senses in smaller sample sizes. parise and figure 1 the graph shows the mean totals for every condition for all participants. the y=axis is the taste perception ratings scale (full scale 0-10). the x-axis contains every single stimulus condition used in the experiment (e.g. ‘c1b’ is note c, pitch 1-low and color blue). figure 2 the y-axis depicts a scaled version of the taste perception ratings range (full scale 0-10). the x-axis depicts the different colors used in the experiment. the horizontal lines show the pairwise comparison significance values between the low and high scoring colors. spence [22] found synesthetic associations in a sample size as small as 12; this was however between traditional synaesthetic congruencies like pitch and visual size or brightness. these associations are built into our sensory systems from birth and so are formed more quickly and are present in more people [23]. in this study red had the strongest link to the sweet taste, however it was not proven that it has a connection to the sound variable (high pitch) that was also linked to the sweet taste. therefore even if two variables have shown associations separately with a certain taste group, there is no guarantee that they are compatible together. 6. future work in the future the test could be repeated by using tones instead of chords as they contain less complex timbres and so a more general understanding of the sound could have been formed, for non-musically trained participants. another idea of further research could be to involve a lighter shade color condition to go with the higher pitch level condition. this would provide two levels of each stimulus and a semantic correlation possibility. this could help to unify the perception and achieve a unified cultura e scienza del colore color culture and science | special issue on food color | 05 | 2016 | 49 54 54 chambers p. et al. issn 2384-9568 doi: 10.23738/ccsj.i52016.06 association of color and sound in relation to taste perception. also the experiment could be modified to include descriptive words of a taste instead of using an actual taste stimulus. this would keep the experiment in the realm of semantics and could provide new cross-modal associations between the words used. 7. conclusions the conclusions that can be drawn from the study are that warmer, brighter colors can increase the sweet taste perception of a sweet taste stimulus. it was also found that the sweet taste was enhanced more under the higher pitched (c4) piano music as opposed to the lower pitched music. it can therefore be concluded that the pitch of an audio sample can affect a person’s flavor perception. this shows that information from outside the traditional gastronomical senses can have an impact on a person’s taste response. however, the main conclusion is that a relationship between color, sound (pitch and note) and taste was not established in this experiment which could mean that there are no associations between the three stimuli used in this study but it could also entail that the particular stimuli choices may not have been compatible. 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[18] a. hasenbeck, s. cho, j. meullenet, t. tokar, f. yang, e. huddleston and h. seo, ‘color and illuminance level of lighting can modulate willingness to eat bell peppers’, journal of the science of food and agriculture, vol. 94, no. 10, pp. 2049-2056, 2014. cultura e scienza del colore color culture and science 45 cultura e scienza del colore color culture and science | 09 | 2018 issn 2384-9568 1andrea siniscalco andrea.siniscalco@polimi.it 2gianluca guarini info@gianlucaguarini.it 1department of design, politecnico di milano 2rendering per architettura digital visualization of a luminaire: from blueprint to photorealistic representation abstract in this article we will discuss how to closely digital represent the aspect of a luminaire and the photometric distribution of the light emitted by it. you will find a comparison of different modeling techniques used to obtain in a quick and efficient way a clean 3d model of a lighting fixture. a model that should also be, with minimum settings, scalable in terms of level of detail depending from the visual importance of the product in the scene. this will avoid too long rendering times and heavy geometry that could be difficult to manage. we will also investigate what could be an optimal procedure to couple the 3d model with photometric data taken from manufactures or measured in a laboratory. keywords light, color, luminaire, visualization, digital representation, 3d, photometry citation: siniscalco a. and guarini g. (2018) ‘digital visualization of a luminaire: from blueprint to photorealistic representation’, cultura e scienza del colore color culture and science journal, 09, pp. 45-54, doi: 10.23738/ccsj.i92018.05 received 07 july 2017; revised 15 november 2018; accepted 21 april 2018 andrea siniscalco, msc in industrial design in 2002. phd in design and methods of product development in 2007. vice director and teacher in the master in lighting design & led technology of politecnico di milano. teacher of digital modelling of space, lighting theory at the school of design. fields of interest are lighting design, visual perception and computer graphics applied to lighting. gianluca guarini, msc in construction engineering in 1999. freelance 3d artist, teacher of autocad and 3dsmax in private training companies. expert in 3d modeling and rendering. tutor of the master in lighting design and led technology of politecnico di milano. professor of politecnico di milano at the school of design. fields of interest are cad 2d design and computer graphics applied to design visualization. 46 cultura e scienza del colore color culture and science | 09 | 2018 | 45 54 siniscalco a. and guarini g. issn 2384-9568 doi: 10.23738/ccsj.i92018.05 1. introduction the continuous increase of the computational power of today’s computers and the possibility to get fast results, contributed to the diffusion of 3d representation software used by designers to produce the so-called photo realistic renderings. the goal of these images, usually, is to show what should be the final appearance of the project. very often, unfortunately, these representations are the result of empirical graphic representation based in the best cases, on the experience of the designer and his ability to achieve images that should be similar enough to what he plans to realize. however, when these forecast images are produced without a precise methodology in the management of virtual materials or the importing and integration of technical data of lighting products usually the resulting digital images, although their strong visual impact, do not match the final appearance of the project a once put in place. having a beautiful image to present to the clients may help the designer to get the job, but in the end, if the real scene, with all of its luminaires, finishes and materials, is too different from the virtual image presented, there can be problems with the clients. this article is part of a wider work on representation and is meant as a help for designers willing to apply modelling and representation techniques that are quick, efficient and that should better represent the appearance of selected lighting fixture. our aim is to describe some practical techniques of modeling and representation of lighting fixtures itself in virtual projects, rather than their impact in the whole space, while maintaining both photo-realism and photometric accuracy. to create a correct digital duplicate of the luminaire in terms of geometry, material, aspect and distribution of light is not a simple task. these procedures can be used in the most common 3d software for modeling and representation. 2. modeling the luminaires considering the fact that there are few studies often designers, in order to speed up the modeling process, makes use of 3d models available online from the manufacturer’s website or portal/libraries dedicated to 3d computer graphics. unfortunately, these models are not always optimized for the production of forecast images, for various reasons. some time they are conversion of models that have been created for the cnc (computer numerical control) of the objects, so with the purpose of the realization of a physical model; or maybe with a completely different set of features. this can result in the first case in a model with excessively many polygons and in the second, a model that can have “inverted normals”, that results in visible “holes” in the surfaces of the objects. if the model of the product found is not suitable, the better choice is to rebuild it, starting by defining the desired level of detail and therefore the modelling technique that allows the designer to obtain good results in an efficient way, always thinking to the final representation since early modelling. the level of detail of the geometries is fundamental in order to not to waste time, needed for modeling and for rendering. the designer should be aware of the visual importance of the geometries in the images that he wants to produce, whether the objects will be represented in the foreground, the background or in an intermediate situation. a good approach is that the modelling techniques used may allow changes in the resolution of the 3d mesh of the model, increasing the detail of the geometry in relation to the importance of the model in the scene, using for instance subdivision modelling techniques. the choice of the best modelling technique depends mainly from the geometry of the luminaire that can be made of one single piece or by multiple components. in this case it is possible to use more than one technique. if the model can be assimilated to basic geometries, it might be enough to use the csg (constructive solid geometry) modelling. the primitives available in most of the software, such as cubes, spheres, cylinders, cones, toroid, etc., are transformed with basic operations like move, rotate, scale, copy, etc. if the model turns out to be more complex, but still can be built with operations of addition, subtraction or intersection between two or more solids, it is possible to use the so-called boolean operations. these are very fast in order to obtain complex geometries even if they can cause two order of problems: visual continuity between the polygons that appear as unwanted shadows on the surfaces and issues in the organization of the polygonal structure of the model, the topology. the modelling based on 2d shapes is ideal in case of long, flat, thick objects, so extrusion or taper operations can be effective. many lighting fixtures can be assimilated to 2d profiles that can be revolved around a specific axis. the “lathe” command, present in most of the modeling software, may allow the designer to obtain these geometries quite easily. for parts such as cables, filaments, springs, it is possible to use modeling tools such as sweep or loft (d’agnano, 2008). sweep allows the creation of 3d geometries by 47 cultura e scienza del colore color culture and science | 09 | 2018 | 45 54 digital visualization of a luminaire: from blueprint to photorealistic representation issn 2384-9568 figure 1 sweep tool example of the use of the sweep tool. on the right, it is possible to see the circle that will act as profile running on the path (in this case a curve). on the left the resulting geometry making a profile, that can be generated by the user or sometimes available on a library, “run” along a curve path keeping its perpendicular aligned to the tangent of the path itself. the operation done by the loft tool is similar to the one of the sweep tool, but with more options. it is possible to change the profile, scale, rotate or twist it, along the path, modifying the resulting geometry. if no one of the previous tools can be used efficiently, the modelling technique that allow the designer to reproduce the most complex shape is the polygonal modelling (daniele, 2008). generally, the easiest approach is to start from flat surfaces mapped with a raster image of the technical drawings; the so called “blueprints” used as planes of projection. it is possible to begin from a primitive solid or even a single polygon and rebuild the entire object by moving and/or adding vertices and polygons. when possible it is good practice to begin by realizing a low-poly model and then increasing the complexity of the geometry at will, by using a “subdivision tool”. this procedure split up the interested polygons in four parts and allow the user to “relax” the adjacent polygons, also divided, creating a smoother appearance of the surfaces. the process can be repeated more times intervening on the number of iterations. it is necessary to pay attention to the number of iterations applied, because for each one, the number of polygon of geometry quadruplicates, increasing exponentially the weight of the 3d model and the time needed to calculate the renders. in order to decide how many iterations are needed for a model, as previously mentioned, the designer should know the importance of the object in the scene; for close objects, the number of iterations will be much greater than for objects in the background. 3. photometry once achieved the goal of a balanced 3d model in term of quality and weight, it is necessary to transform the obtained geometry into an actual light source that can be used to render the final scene. a desirable thing should be to use the software as a verification tool and not just to produce attractive images; for instance, how my project will look like if i choose one luminaire instead of another. in order to do so, it is necessary that the software in use comes with calculation algorithms that approximate in a plausible manner, the real light distribution in space. this is possible only when indirect light is actually calculated by the interaction of the emitted light and the surfaces of the scene, and not simulated with hypothetic parameters that modulate the amount of light diffused in the scene, such as ambient light, for example. in software used to do lighting verification, these calculations were once made by the algorithm of radiosity, which allowed the simulation of light evenly diffused by lambertian surfaces and soft shadows. the results, were integrated by ray tracing algorithms that were dedicated to calculate specular reflections and sharp, defined shadows. more recently, software specialized in figure 2 iterations example of increase in the number of polygons in relation to the number of iterations choices for the object 48 cultura e scienza del colore color culture and science | 09 | 2018 | 45 54 siniscalco a. and guarini g. issn 2384-9568 doi: 10.23738/ccsj.i92018.05 light calculations have been updated with more recent algorithms such as photon mapping or the rapidly diffusing physically based algorithms. that said it must be clear to the designer that it is not possible to get reliable results by using the “classic” light sources of computer graphics (such as opengl ambient, point, directional, spot). real luminaires, in most cases, have a spatial distribution of the lighting intensity more complex than those achievable through opengl lights. as an example, it is very easy to understand that the light distribution in space of a road luminaire has nothing to do with the one of a table lamp or a retail premise spotlight. each luminaire has a specific light intensity distribution, which is the result of interaction between the lamp and the optical system of the device, generally designed to meet specific project requirements. 3.1 photometric files the shape of light emission in luminaires, is generally measured by using a laboratory instrument called goniophotometer that performs an angular emission investigation and saves the results in ascii files containing, along with other parameters, a set of coordinates and values, that put in relation spatial angles with the light intensity emitted by the luminaire. these files are generally called photometric files or photometric webs. these shapes are eventually more complex than the basic opengl lights. the photometric files are generated in different formats (mostly in relation to the nation in which they are acquired/crated) such as eulumdat *.ldt europe (stockmar, 1999), iesna *.ies america (ansi/iesna, 2008), cibse tm14 *.cib united kingdom (cibse, 1988), ltli *.ltl denmark (uni en 13032-1, 2012). in addition to these standard files there are also several proprietary formats used by specific lighting design software, such as the format *.uld of dialux (dial gmbh, 2018), the format *.oxl of litestar (oxytech srl, 2018) or the format *.rolfz of relux (relux informatik ag, 2018), that are often integrated with a 3d model that is usually given by the luminaire manufacturer, and unfortunately, not always properly modelled. obviously these latter formats are read only by their software, whose main purpose is not really the photorealistic rendering, but rather the photometric verification, and cannot be opened with the most common software used for photorealistic renderings. the choice given to the designer is to import common photometric files such as eulumdat, or other open formats like iesna, cibse, ltli, which can simulate the actual light distribution of the luminaire, but still, not their physical appearance. in order to reproduce the appearance of a lighting fixture it is necessary to couple the geometric model to its corresponding photometric web that usually is available from the manufacturer or measured with a gonio-photometric relief in a laboratory. 3.2 pairing 3d models and photometric files after modelling the geometry of the luminaire with the methods suggested in paragraph 2, it is necessary to place a light source whose emission properties will be those of the photometric solid. the photometric files are related to a point in space that emits light with different intensities as vectors in space. in the physical reality, these intensities are the result of the interaction between the light emitted by sources like discharge in gas, burner or led and the optical system of the luminaire, for example: reflector, refractor, lenses, filters, etc. it is necessary to remember that the measured photometric file already considers these interactions. consequently, it is important that the threedimensional model of the luminaire, does not alter the emission of the photometric web, like for instance, by cutting her off. in many software, this is possible by editing the properties of the light source so that some objects do not interact with the light; specifically, by not casting any shadow. an example of object that may be set with these properties are those of the part of the luminaire that emits light, in which the photometric web will probably be placed. in order to complete this task correctly, the designer need to place the photometric web in a correct way according the modelled geometry. logic would suggest placing the photometric web in the same position where the light source is found in the real luminaire. in reality, the solution is not so simple. considering that photometric webs are considered to be points; where to place them when the light source is widespread? what is the correct placement position when inside of the luminaire there are multiple lights sources, such in the case of led lighting fixtures? figure 3 -light sources from left to right, different generic light sources commonly used in 3d software: point, spot, ambient and directional. the far right shows the photometric web of a real lighting fixture (mellow light iv by zumtobel) 49 cultura e scienza del colore color culture and science | 09 | 2018 | 45 54 digital visualization of a luminaire: from blueprint to photorealistic representation issn 2384-9568 figure 4 photometric center to the left (in blue) some guidelines for the identification of the photometric center (also called photometric zero), marked in red, as prescribed by the european standard uni en 13032-1. to the right (in green), some of the prescription provided by the american standard iesna lm-63-02. if the purpose is the photometric accuracy and the program allows you to exclude parts of the geometry from the lighting calculation, the correct position is that of the photometric center of the luminaire. the photometric center is defined as the point where the luminaire is aligned with the goniophotometer during the relief in which the photometric file is generated. the correct position of this point is described by the standards for the measurement of light fittings, which may vary from country to country (for instance america and europe) and result into the generation of different photometric files. it is possible to consider the photometric center as the locus from which the light is emitted, and therefore, it should be considered as the point of junction between the geometry of the 3d model and the photometric files. the operation of identification of the photometric center is easier for the categories described by the standard. nevertheless, for some luminaires with very complex shapes, it is necessary to use some simplifications and adjustments, but this happens for the gonio-photometric relief as well. for instance, a complex chandelier will hardly have a photometric file, but if the file exists, it will be hardly described in the standard. in this case, the designer should look at the shape of the photometric web, at the position of the light sources by looking to a catalogue or the brochure of the product, and deduce the position of the photometric center that in most cases, correspond to the center of the geometry of the light emitting part of the fixture. 4. color a fundamental problem in the representation of the luminaires and light in general, is related to the limits of the representation devices. the computer-generated images are mostly produced to be displayed on video; it can also happen that these images are printed, maybe with high resolution but still, the devices typically used for digital representation, are unable to compete with the dynamic of the physical reality and the human perception. this is true regarding both the luminance contrasts, and the spectral component of light. having to use a representation device as an example, a monitor, all of the colors usually are converted to rgb triplets. a simple mix of three components it is not enough to compose light in physical reality; an electromagnetic radiation composed by different wavelengths of which, our visual system can perceive only the portion between 380 and 780 nanometers: violet, indigo, blue, green, yellow, orange and red. given this, it is also necessary to specify that often the light sources commonly used in luminaires, have nonlinear emission spectra that might be incomplete or in bands that peaks in certain colors; very different form that of the sun. for this reason, some light sources are less effective in color render. under these light sources, some colors appear to be dull and grayish. the chromaticity of a computer generated light source, must necessarily be converted into an rgb triplet in order to be represented by common monitors, which are matrices of rgb leds. also, because the user have to decide the color of a light source within the modelling software, the most used method is still rgb. sometimes color presets are available in the software, for example relating to different sources or different color temperatures, but even if the chosen values recall the real physic in practice, the light is colored only by changing the rgb values and it is hardly able to represent different color rendering indexes. some rendering programs (randomcontrol slu, 2017) (fluid interactive inc, 2015) (glare technologies limited, 2018) (luxrender, 2018) (nvidia, 2015) (wenzel, 2010) (otoy inc, 2017) (solid iris technologies. 2012) (eclat-digital recherche, 2013) implement algorithms able to mimic the spectral behavior of light, displaying the color by simulating the spectral colors with a given spectral step, for example simulating the properties with steps of 10nm. there are many ways to implement these algorithms, but generally, although they allow higher accuracy in the calculation of color simulating more correctly phenomena such as the spectral dispersion or the lower colorrendering index of some light sources, this cost globally in terms of greater complexity and the 50 cultura e scienza del colore color culture and science | 09 | 2018 | 45 54 siniscalco a. and guarini g. issn 2384-9568 doi: 10.23738/ccsj.i92018.05 need of longer computational times. the same concepts are valid also for the materials applied in the scene, commonly called “shaders”, which by reflection, refraction and transmission, should affect the spectrum of light by dispersion or by reflecting or transmitting only certain wavelength and thus, changing the color of light. if the will of the designer is to remain faithful to the physics of real world, it is necessary (radziszewski et al., 2009) to use a software that calculates light and its interaction with materials with a full spectrum algorithm. 5. case studies five case studies of digital representation of real luminaires will be described below, but before starting, a little premise is necessary: the described techniques, both for modelling and for rendering, are not the only ones that can be used. the focus is to achieve models that are clean, efficient and with a level of detail that can be increased or decreased at will. the software used for these case studies purpose is 3d studio max 2016 by autodesk, but these techniques can be easily reproduced in any compatible modelling software. the choice fell on 3dsmax because it is one of the most diffuse modeling software for design visualization. it also offers a wide set of tools that allow the user to approach the modeling with different techniques. moreover, a lot of reference and tutorial can be easily found on the web in order to help the user to learn how to use it. other specific software such as dialux, relux, agi32 or litestar, specifically designed for lighting, are commonly used for the evaluation of the lighting project, but their modeling tools are very simplified and also, they usually have proprietary files that already implement the system 3d model – photometric file, as said in 3.1. the first case is a very simple luminaire, that can be modelled with csg, extrusion of spline and very simple polygonal modeling. the amount of detail is derived by the parameters embedded in the primitives the second case shows how an inner part of a luminaire can be simplified because not directly and totally seen. instead the numerous and external items are the most accurate and prepared for subdivision, done with a single instance of a sphere modified with poly modelling. the third one lends itself to the use of boolean operation, refined with few steps of poly modeling to obtain clean results. also the revolution tool (lathe) to curve primitives will be the best choice. it will be evident, that to prefer one technique more than another will be a decision driven by the shape of the object or of its main component. when possible an approximation with parametric primitives is to be preferred. when it is not, an analysis of the geometry will tell us how to proceed. if by combining or subtracting the geometry, extruding or revolving a curve, giving thickness to lines and curves. where all of this techniques cannot help, direct polygonal editing is the suggested approach to solve the problem. a clean topology obtained with this technique is also the best starting point to have a scalable 3d object in terms of level of detail. 5.1 evoluzione by disano illuminazione evoluzione is a very common luminaire that mount fluorescent linear lamp produced by disano illuminazione. the simple, straightforward design is also reflected on the simplicity of the modelling process. the luminaire can be replicated with five geometric shapes: a parallelepiped for the external shell, an extruded profile for the aluminum reflectors, cylinders for the lamps, other parallelepipeds for the lamp-holders and the side abutment. the external shell is obtained by a parallelepiped, where the lower face has been refined into a new smaller polygon that has been then removed. the thickness of the shell is obtained by using a command that create a series of polygons parallel to the existing ones for simulating the thickness of the element. usually this command is called “shell”. the profile of the reflector is extruded for the length of the luminaire, and closed at the sides, by the abutments, created by two parallelepipeds. these two elements are placed inside of the external shell. the fluorescent lamps are obtained with four cylinders. the use of the standard parametric primitive gives the possibility to easily increase or decrease the number of faces in the model. a polygonal modification of a parallelepiped, allow the designer to create the lamp holders. after the model is created, it is necessary to find the correct photometric file to couple with the model. as in most case, these files can be downloaded from the website of the manufacturer. to place the photometric web in the photometric center, the designer should look at the standard. in this case, both the american and european standards states that the photometric center is in the lower center of the luminaire. this means in the intersection of the median axes at the height of the lower face of the external shell. it is important not to modify the values of intensity inherited by the photometric file, even if the software allow the user to do so, because these are the actual measured values of the luminaire. a problem should be very visible at this point: 51 cultura e scienza del colore color culture and science | 09 | 2018 | 45 54 digital visualization of a luminaire: from blueprint to photorealistic representation issn 2384-9568 figure 5 evoluzione basic geometry basic geometric components for the 3d modelling of evoluzione by disano illuminazione. figure 6 evoluzione comparison from left to right: picture of the luminaire, geometric model of the luminaire (red sign indicates the photometric center) and production render of the luminaire. how it is possible to simulate the appearance of the four luminous tubes with just one photometric file that, in this case, emits only downwards. only by using the photometric file, this is impossible. the tubes appear dark, even if the luminaire is emitting light. to solve this, it is necessary to use a little trick. first, it is necessary to assign the correct materials to the geometry, paying attention to the energy balance of materials, because it is necessary to reproduce the right finishes and the right index of reflection/transmission/refraction of each part of the model. for evoluzione, the external shell is a highly diffusive painted white metal with a small reflective component, around 65% diffusive and 5% reflective. except the tubes, the other parts are made of brushed aluminum with 70% of specular reflection with glossiness lowered to 50%. to obtain the fluorescent tubes, it is necessary to use a self-illuminating material for the simulation of the light that comes out from the tubes. fortunately, most of the rendering engines include this kind of shader. two important elements must be considered while using such material: first, the self-illumination effect must be visible in the reflections of the other components and second, the light emitted by the self-illuminated material must be ignored in the global calculation of the scene. this because if the light of the self-illuminated material is computed, it will invalid the luminous emission of the photometric file, producing incorrect results. 5.2 caboche suspension by foscarini caboche is a quite complex suspension luminaire to model. it is composed by a structure made by arcs and circles, a central luminous body, many decorative refractive spheres, wires and cable and the ceiling strut. the lattice of arcs and circle can be simulated and simplified with the use of a standard torus primitive. once the center lower and upper faces of the toroid have been removed, the mesh topology can be converted in a wire cage with a thickness decided by the user. for example, in 3ds max this can be done with the use of the “lattice” modifier. in this command it is easy to fine tune the number of segments with a parametric value. the decorative spherical elements can be modeled with the standard sphere primitive, with the lower part modified with few step of polygonal modeling. as the refraction of light trough these spheres is the core aspect of this luminaire, it is indispensable that these elements are calculated as solid thick geometry. since these refractive sphere are present in large amount, it is a good idea to use a subdivision technique to the instanced elements, in order to reduce the weight of the model with one single parameter in case of shoots with the luminaire far from the camera. the luminous body is obtained with the lower part of a sphere primitive. also in this case the polygon modeling technique helps refining the upper part of the object. the same process defines the strut on the ceiling. the cuts in the geometry in which the electrical wires pass trough are done open chamfering a corresponding selected set of edges. 52 cultura e scienza del colore color culture and science | 09 | 2018 | 45 54 siniscalco a. and guarini g. issn 2384-9568 doi: 10.23738/ccsj.i92018.05 figure 7 caboche basic geometry basic geometric components for the 3d modelling of caboche by foscarini. figure 8 caboche comparison from left to right: picture of the luminaire, geometric model of the luminaire (red sign indicates the photometric center) and production render of the luminaire cables and suspension wires are created with linear lines and splines. it is possible to create these elements and then use a command to assign them a thickness of a given dimeter or, in alternative, using the “loft” tool. the materials for caboche are an opaline blown glass for the luminous body, pmma for the spheres, polycarbonate for the arches, stainless steel for the suspension cables and transparent electrical cable for the power supply. the crucial element of this product is the crown of spheres that refract light coming from the luminous element placed in the center. to achieve this effect, the spheres must be considered as solid geometry so it will be possible to put in evidence the refraction; the index for the pmma is around 1.49. other materials should not be difficult. the position of the photometric center, following the indications (figure 5, profile 10) of the european standard, is in the center of the suspended element and not inside of the luminous body as logic may suggest. it is also important to pay attention to the orientation of the photometric web. in this case, for example, the emission of the luminaire is both direct and indirect. the designer must identify the right orientation of the emission by looking at the polar diagrams of the luminaire on the catalogue or the manufacturer’s website. in this case, the higher intensities are pointing downwards, so the photometric web must be oriented accordingly. 5.3 aoy by flos this luminaire is made by one glass cylindrical main body, a goblet, a reflector and a light bulb. the glass cylinder can be obviously replicated with the corresponding standard primitive, paying attention to the amount of segments at the base circle section. being the main and bigger body of the luminaire, the circumference of the body should be obtained at least with 32 segments. this should be the minimum choice for a foreground / medium distance camera view. the arch at the base of the cylinder is obtained by subtracting with a boolean operation, a second cylinder primitive. in order to clean up the topology, the resulting object should be refined with polygonal modelling, removing the unnecessary polygons and vertices created by the subtraction. to create a more correct model, the opaline goblet inside of the cylinder need to have the same amount of segments. a fast and easy way to obtain this result is to extrude the upper part of the glass cylinder downward and then detaching it from the rest of the body. the upper reflector is created by revolving a curve along the vertical axis, this can be done with a “lathe” tool, taking care of setting the number of segments equal to the ones of the other parts of the luminaires. a revolution can be also used to create the two elements that form the light bulb. 53 cultura e scienza del colore color culture and science | 09 | 2018 | 45 54 digital visualization of a luminaire: from blueprint to photorealistic representation issn 2384-9568 this last object aside, the first three elements need to have a certain thickness, so the “shell” command must be used. also in this model, it is possible to use subdivisions in order to adapt the resolution of the polygonal mesh in relation to the position of the luminaire in the scene. the external body is made of clear glass and the internal diffuser and reflector are made of white, opaline glass. the light source is a bulb, with the upper half with a chrome finish that serves as anti-glare system. the position of the photometric web in this case is not in the center of the luminaire, but in correspondence of the light source. the european standard states that for luminaires with transparent sides or without side features, the photometric center corresponds to the lamp photometric center. another element to keep in consideration is that this fixture, in dark environments, creates a slight caustic effect at the base of the luminaire. in order to achieve so, the software used must have a render algorithm that is able to calculate caustics, and the effect has to be set up properly. the opaline diffuser and reflector may need a little improvement with a self-illuminated material. to achieve the caustic effect and for physical correctness, they also must be removed from the calculation of shadows together with the bulb. figure 9 aoy basic geometry basic geometric components for the 3d modelling of aoy by flos. figure 10 aoy comparison from left to right: picture of the luminaire, geometric model of the luminaire (red sign indicates the photometric center) and production render of the luminaire 6. conclusions the techniques described can change in relation to the software used and the shape of the luminaires as it can span from very simple to incredibly complicated. all the objects can be created in many ways, but the techniques described are efficient and allow the designer no to worry about the weight of the model, that can also directly affect the calculation time. in synthesis, the important steps are: • the study of the luminaire: geometry, photometry and materials, directly on the catalogues or manufacturer website. • what to represent; hidden components, for instance, should not be modelled. • select the most efficient technique to model all the visible parts. • scalability: trying to grant the possibility to change the resolution in relation to the importance of the luminaire in the scene. •correct position of the light sources when coupling the photometric data with the geometry. attention in placing the photometric web in the correct spot according with the standard in use. •creating the visual aspect of the object; materials and properties to set in order to respect the physics of the real world, and overcoming the limitations of the system geometry/photometry. 54 cultura e scienza del colore color culture and science | 09 | 2018 | 45 54 siniscalco a. and guarini g. issn 2384-9568 doi: 10.23738/ccsj.i92018.05 funding this research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. conflict of interest the author declares that nothing has affected his objectivity or independence in the production of this work. neither the author nor his immediate family member have any financial interest in the people, topics or companies involved by this article. neither the author nor his immediate family member had a professional relationship with the people and companies cited in this article. neither the author nor his immediate family member are involved in a legal dispute with the people and the companies cited in this article. no conflict of interest including financial, personal or other relationship with other people and organization within three years of beginning the submitted work that could inappropriately influence, or be perceived to influence, this work. bibliography d’agnano f. (2008), “3ds max per l’architettura” apogeo daniele t. (2008), “poly-modelling with 3ds max: thinking outside of the box” focal press stockmar a. (1999), eulumdat file format specification available at: http://www.helios32.com/eulumdat.htm (accessed: 18 april 2018) standard ansi/iesna lm-63-02 (r2008), “standard file format for electronic transfer of photometric data” cibse tm14 (1988), “standard file format for transfer of luminaire photometric data”, chartered institution of building services engineers uni en 13032-1 (2012), “luce e illuminazione misurazione e presentazione dei dati fotometrici di lampade e apparecchi di illuminazione parte 1: misurazione e formato di file” dial gmbh (2018). available at: https://www.dial.de (accessed: 18 april 2018) oxytech srl (2018). available at: http://www.oxytech.it/ (accessed: 18 april 2018) relux informatik ag (2018). available at: http://www.relux. biz/ (accessed: 18 april 2018) arion randomcontrol, slu (2017). available at: http:// www.randomcontrol.com/arion (accessed: 18 april 2018) fluid interactive inc. fluidray (2015). available at: http:// www.fluidray.com/features/technical-specs/#tab-id-3 (accessed: 18 april 2018) glare technologies limited indigo renderer (2018). available at: http://www.indigorenderer.com/features/ technical (accessed: 18 april 2018) luxrender (2018). available at: http://www.luxrender.net/ wiki/features#physically_based.2c_spectral_rendering (accessed: 19 april 2018) nvidia mental ray (2015). available at: http://docs. autodesk.com/mentalray/2014/chs/mental-ray-help/ files/manual/spectral.html (accessed: 19 april 2018) wenzel j. mitsuba renderer (2010). available at: http:// www.mitsuba-renderer.org/ (accessed: 19 april 2018) otoy inc. octane (2017). available at: https://home.otoy. com/render/octane-render/features/ (accessed: 19 april 2018) solid iris technologies thea renderer (2012). available at: https://www.thearender.com/site/index.php/features. html (accessed: 19 april 2018) eclat-digital recherche ocean (2013). available at: http:// www.eclat-digital.com/spectral-rendering/ (accessed: 19 april 2018) radziszewski m., boryczko k., alda w. (2009), “an improved technique for full spectral rendering” journal of wscg vol. 17, no. 1-3, václav skala union agency cultura e scienza del colore color culture and science 7 cultura e scienza del colore color culture and science | 07 | 2017 issn 2384-9568 anna luana tallarita info@annaluanatallarita.com utad/iade/grupo de geociancias red: the symbol in history abstract this article presents historical information and curiosities on the red. as a symbol, color present in human nature and its representation. color is an integral part of the perception of space and objects in which the person relies. from the etymological point of view, the word red comes from rubeum corradical rubeum. in latin it is indicated by the terms rutilus and ruber which conceptually represent the meaning of: blood and life. red is the symbol of body and matter. red is also the color of fire, heat, energy. fire is the basis of light that is dimensioned in that part of the day when human action takes place and for this reason represents action in general. red and shell were the first symbols used by the individual as personification of blood and water, representing how the symbol precedes the sign. red ocher has a primary importance in burial rites. red is linked to the inoculation of the dead and to rites of rebirth. keywords red, power, life, symbol, sign, death citation: tallarita a. l. (2017) ‘red: the symbol in history’, cultura e scienza del colore color culture and science journal, 07, pp. 07-11, doi: 10.23738/ccsj.i72017.01 received 20 june 2016; revised 30 may 2017; accepted 31 may 2017 italian translation provided: ‘arte e colore nella riqualificazione della città e del paesaggio red’ anna luana tallarita jazz singer, composer, anthropologist and creative artist working in different forms to express a colored complex intercultural reality. published writing, disks, videos, plasticworks, and worked throughout europe and south america and lives between lisbon and milan. in 1999-2017 (2015 phd) she studied at the italy france e portugal. member: utad-iade-geoscience group. 8 cultura e scienza del colore color culture and science | 07 | 2017 | 07 11 tallarita a.l. issn 2384-9568 doi: 10.23738/ccsj.i72017.01 1. red: the symbol in history color is an integral part of the perception of space and objects in which the person relies. from the etymological point of view, the word red comes from rubeum corradical rubeum. in latin it is indicated by the terms rutilus and ruber which conceptually represent the meaning of: blood and life. the word red in greek is ἐρυθρός, -ά, -όν erythros φοινικοῦς, -ῆ, -οῦν foinikus; adjective red; while φοινίκιος, -α, -ον foinikus; is purple red, locust. red is the symbol of body and matter. it opposes white and black, considered in their sense of light and darkness, and with which in the middle ages it formed a symbolic triad. a symbolism, that linked to the red that vertically and horizontally crosses the history of humanity from life to death. probably this substance represented the blood and the beginning and end of life, in fact, neanderthal [1] and cro-magnon peoples used red ocher [2] for funeral rites or fertility whose basic component is both a mineral and a color. fe2o3 hematite owes its name to the greek word hema which means just blood. red ocher has a primary importance in burial rites. the places where the bodies were buried, were carved with red ocher, which was used to color the skeletons. red is linked to the inoculation of the dead and to rites of rebirth. the meaning of colors in various places on earth has not always represented the same symbologies, in ancient egypt, for example, called kemet black earth, black color has no negative value as the color of the silt and the lender of life. while this happened, the red had it and was interpreted in its negative qualities by being tied to seth osiris’s killer with red eyes and hair. the representation of its red coloring could then assume the meaning of evil or victory depending on the context in which it is interpreted. the ancients used it to protect themselves from the fire and it was the color of isis, the goddess in fact depicted as a woman dressed in a long red tunic which is the symbol of the bride, and the protector of the sailors 2. symbology of red and religion red and shell were the first symbols used by the individual as personification of blood and water, representing how the symbol precedes the sign. its universality lives in the representation of reality, not translated from the sign into its mere representation. in early christian art the archangels and the seraphim were painted red, which was considered the color of earthly and spiritual love and also the color in the image of the sacred heart of jesus where we finds the rays symbols to suggest the light, and the light 1. rosso: il simbolo nella storia il colore è parte integrante della percezione dello spazio e degli oggetti con cui la persona si relaziona. dal punto di vista etimologico la parola rosso deriva da russum corradicale di rubeum. in latino è indicata con i termini rutilus e ruber che concettualmente rappresentano il significato di: sangue e vita. la parola rosso in greco è ἐρυθρός, -ά, -όν erythros φοινικοῦς, -ῆ, -οῦν foinikus; rosso aggettivo; mentre φοινίκιος, -α, -ον foinikus è il rosso porpora, locuzione. il rosso è il simbolo del corpo e della materia. si oppone al bianco e al nero considerati nella loro accezione di luce e oscurità e con cui nel medioevo ha formato una triade simbolica. una simbologia, quella legata al rosso che attraversa verticalmente e orizzontalmente la storia dell’umanità dalla vita alla morte. probabilmente questa sostanza rappresentava il sangue e l’inizio e la fine della vita, infatti i popoli di neanderthal [1] e di cro-magnon usarono l’ocra rossa [2] per riti funebri o di fertilità il cui componente base è sia un minerale che un colore. l’ematite fe2o3 deve il suo nome alla parola greca hema che significa appunto sangue [3]. l’ocra rossa è di primaria importanza nei riti sepolcrali. le fosse dove venivano seppelliti i cadaveri erano spalmate di ocra rossa, che veniva usata per colorare gli scheletri. il colore rosso è legato all’inumazione dei morti e ai riti della rinascita. il significato dei colori nei vari luoghi della terra non ha sempre rappresentato le medesime simbologie, nell’antico egitto ad esempio che è chiamato kemet terra nera, il colore nero non aveva valenze negative essendo il colore del limo e apportatore di vita. mentre era proprio il rosso ad averne e ad essere interpretato nelle sue valenze negative essendo legato a seth l’uccisore di osiride che aveva gli occhi e i capelli rossi. la rappresentazione della sua colorazione rossa potrebbe quindi assumere il significato di male o di vittoria a seconda del contesto in cui è interpretato. gli antichi lo usavano per proteggersi dal fuoco ed era il colore di iside [4], la dea infatti viene raffigurata come una donna vestita con una lunga tunica rossa che è il simbolo della sposa [5], e della madre protettrice dei naviganti. 2. simbologia del rosso e religione il rosso e la conchiglia sono stati i primi simboli usati dall’individuo in quanto personificazione del sangue e dell’acqua, rappresentazione di come il simbolo preceda il segno [6]. la sua universalità vive nella rappresentazione della realtà non tramutata dal segno in una sua mera rappresentazione. nell’arte paleocristiana si 9 cultura e scienza del colore color culture and science | 07 | 2017 | 07 11 red issn 2384-9568 flame suggests heat where red is the color of the heart. st. john will say: this is he who came with water and blood, jesus christ; not with water alone, but with water, and with blood. and it is the spirit that beareth witness, because the spirit is the truth. because three are the ones that bear witness: the spirit, the water and the blood, and these three are in agreement (1 jn 5: 6-8). the symbol in the manifestation made by st. john is that of celestial love but represents its opposite within a symbolic vision of the dialectical unity of the parts. in fact often the devil is represented in red and black colors within the symbols of western culture. in the liturgical colors used by the catholic church of the latin rite, red has various meanings, highlighted by liturgical dresses worn by ministers presiding over the functions and some furnishings present in the church. within the liturgical context they are represented by red: the passion of christ, the holy spirit, and the blood spilled by christ and the martyrs, making them manifest their true royalty that are called princes of the church. tied to carnal love, red in the revelation with purple and scarlet are the colors of the woman representing babylon the great. ...there i saw a woman sitting on a scarlet beast, covered with blasphemous names, with seven heads and ten horns. the woman was dressed in purple and scarlet, (...). on the forehead he wrote a mysterious name: babylon the great, the mother of the prostitutes and the abominations of the earth. then i realized that the woman was drunk with the blood of the people of god and the blood of those who died for faith in jesus (revelation 17: 1-6, cei version). red is also the color of fire, heat, energy, and light as it is in the writings of the apocalypse associated with redemption, in the same passage it will be later read: (...) the monster and the ten horns you saw will hate the prostitute, they will divide its flesh and destroy its remains with the fire. (revelation 17: 15-16, cei version). history attributes to red symbols of power, religion and war. for his ability to refer to the two primary elements that are the fire and the blood, called to be in christendom for example the symbol of the sacrifice of christ and of sins and of deep love and the fire of punishment. in the 13th and 14th centuries the pope, dressed in white, went dressed in red as well as the cardinals who through this color meant to be ready to sacrifice for christ. the paintings will dipingevano di rosso gli arcangeli e i serafini, con quello che era considerato il colore dell’amore terreno e spirituale e altresì il colore nell’immagine del sacro cuore di gesù dove ritroviamo i simboli dei raggi per suggerire la luce e della fiamma a suggerire il calore dove il rosso è il colore del cuore. s. giovanni dirà: questi è colui che è venuto con acqua e sangue, gesù cristo; non con acqua soltanto, ma con l’acqua, e con il sangue. ed è lo spirito che rende testimonianza, perché lo spirito è la verità. poiché tre sono quelli che rendono testimonianza: lo spirito, l’acqua e il sangue, e questi tre sono concordi (1 gv 5, 6-8). il simbolo presente nella manifestazione fatta da s. giovanni è quello dell’amore celeste ma rappresenta il suo opposto all’interno de una visiona simbolica dell’unità dialettica delle parti. infatti spesso il diavolo è rappresentato con i colori rosso e nero all’interno delle simbologie della cultura occidentale. nei colori liturgici utilizzati dalla chiesa cattolica di rito latino, il rosso possiede infatti vari significati, evidenziati dai paramenti liturgici indossati dai ministri che presiedono le funzioni e in alcune suppellettili presenti nella chiesa. all’interno del contesto liturgico sono rappresentati dal rosso: la passione di cristo, lo spirito santo e il sangue versato da cristo e dai martiri, fatto che palesa la loro regalità tant’è vero che vengono chiamati principi della chiesa. legato all’amore carnale, il rosso nell’apocalisse con la porpora e lo scarlatto sono i colori della donna che rappresenta babilonia la grande. …là vidi una donna seduta sopra una bestia scarlatta, coperta di nomi blasfemi, con sette teste e dieci corna. la donna era ammantata di porpora e di scarlatto, (…). sulla fronte aveva scritto un nome misterioso: babilonia la grande, la madre delle prostitute e degli abomini della terra. allora mi accorsi che la donna era ubriaca del sangue del popolo di dio e del sangue di quelli che sono morti per la fede in gesù. (apocalisse, 17: 1-6, versione cei).il rosso è anche il colore del fuoco, del calore, dell’energia e della luce è come tale negli scritti dell’apocalisse gli si associa la redenzione, nello stesso passo difatti successivamente si leggerà: (…) il mostro e le dieci corna che hai visto odieranno la prostituta, (…) divideranno la sua carne e distruggeranno i suoi resti con il fuoco. (apocalisse, 17: 15-16, versione cei). la storia attribuisce al rosso i simboli del potere, della religione e della guerra. per la sua facoltà 10 cultura e scienza del colore color culture and science | 07 | 2017 | 07 11 tallarita a.l. issn 2384-9568 doi: 10.23738/ccsj.i72017.01 feature the red devils as well as other heroes and knights wearing red clothes or accessories, often symbols of animated negative vales, overturning that positive symbolism that in the past represented the red painted angels. a precious color that in the sixteenth century was reserved for the power just as much so that ordinary men no longer sat in red, favoring that the color was reserved to symbolize the power of the popes, cardinals, kings and queens. men would begin to dress blue dresses that until then was a color reserved to women because they called the mantle of the mother of christ: our lady. in the theory of the four elements there are as many correspondences between color and element: fire is red, water is blue and air is white and earth is black. fire is the basis of light that is dimensioned in that part of the day when human action takes place and for this reason represents action in general and as such or as a symbol of the attack and conquest is complementary to the green that represents the color of conservation and defense and symbolizes the god mars, the god of war mars represents the red color in its negative aspect linked to force, violence and bloodshed. like in the christian rite to drink the blood of christ during the eucharistic ritual represented by red wine, along with his body, represented by the consecrated place. in some texts the tibetan magical precepts are mentioned with all kinds of human blood used for the various rites related to it. red is revealed to be in the light of what has so far been exposed in relation to blood as the primary symbol of life and often linked to other symbols such as shells, oysters or pearls, a sign of aquatic cosmology and sexual symbolism. the scholar elijah mircea writes that sexual symbolism indicated the second rebirth created by the initiatory or sepulchral ritual [7]. from anthropologist leroy gourhan also come countless examples of ritual burial made of red ocher and shells. by associating the symbolism of colors and red in particular with such an enormous mythological and social heritage that has come from the representation of the genetic and biological one, we come to understand some other aspects that connect the perceptions of colors to the resulting emotional reactions in the person. the results of these associations can be found in everyday life and are fundamental if they are included in some fields of study related to design, marketing and the economy in general. that is to say that material sphere in which human life is reflected in contemporary anthropological contexts, utilizing the negative and positive values of the colors to induce precise emotional states, for example, for commercial purposes. (al.tallarita-m.cautela) di rimandare ai due elementi primari che sono il fuoco e il sangue, chiamati a essere nella cristianità ad esempio il simbolo del sacrificio di cristo e dei peccati e dell’amore profondo e del fuoco del castigo. nei secoli xiii e xiv il papa, che vestiva di bianco passò a vestire di rosso così come i cardinali che attraverso questo colore volevano significare di essere pronti al sacrificio per cristo. i quadri presenteranno i diavoli rossi cosi come altri eroi e cavalieri ad indossare abiti o accessori rossi, molto spesso simboli animati da valenze negative, ribaltando quella simbologia positiva che anteriormente rappresentava gli angeli dipinti in rosso. un prezioso colore che nel xvi secolo venne riservato al potere vero e proprio tanto da fare sì che gli uomini comuni non vestissero più in rosso, favorendo che il colore fosse riservato a simboleggiare il potere dei papi, dei cardinali, dei re e delle regine. gli uomini inizieranno a vestire abiti di colore blu che fino ad allora era colore riservato alle donne poiché richiamava il manto della madre di cristo: la madonna. nella teoria dei quattro elementi sono presenti altrettante corrispondenze fra il colore e l’elemento: il fuoco è il rosso, l’acqua è il blu e l’aria è il bianco e la terra è il nero. il fuoco è la base della luce che si dimensiona in quella parte della giornata in cui si svolge l’azione umana e per tale ragione rappresenta l’azione in genere e come tale o come simbolo dell’attacco e della conquista è complementare al verde che rappresenta il colore della conservazione e della difesa e simboleggia il dio marte, il dio della guerra marte rappresenta il colore rosso nel suo aspetto negativo legato alla forza, alla violenza e allo spargimento di sangue. come nel rito cristiano di bere il sangue di cristo durante il rito eucaristico rappresentato dal vino rosso, insieme al suo corpo, rappresentato dall’ostia consacrata. in alcuni testi nei precetti magici tibetani sono menzionati tutti tipi di sangue umano utilizzato per i vari riti ad esso connessi. il rosso si rivela essere alla luce di quanto finora esposto in relazione col sangue simbolo primario di vita e legato spesso a altri simboli come le conchiglie, le ostriche o le perle segno della cosmologia acquatica e del simbolismo sessuale. lo studioso eliade mircea scrive in merito che il simbolismo sessuale indicava la seconda rinascita realizzata dal rito iniziatico o sepolcrale [7]. dall’antropologo leroy gourhan provengono altresì innumerevoli esempi di inumazione rituale realizzata con ocra rossa e conchiglie. associando la simbologia dei colori e del rosso in particolare, a un così vasto patrimonio storico mitologico e sociale, sopraggiunto dalla rappresentazione di quello genetico e biologico, si arriva a comprendere alcuni altri aspetti che collegano le percezioni dei colori alle conseguenti reazioni emotive presenti nella persona. i risultati di tali associazioni sono 11 cultura e scienza del colore color culture and science | 07 | 2017 | 07 11 red issn 2384-9568 funding this research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. conflict of interest i do not have conflicts of interest at this time. notes and bibliography [1] 400,000 years ago began the history of color, at a time that the first cultural use of color was made for the decoration of the body. [2] the use of ocher used as dye in wall paintings, movable works, body decorations in the paleolithic in europe, during the middle, gets remarkably intensified in the musterian burial rituals. during the upper paleolithic its use is linked to the color red, blood, life, death. [3] human beings that lived in the middle stone age have employed ritual pigments at least 400,000 years ago: this is the result of the excavations of prof. l. barham of the university of liverpool, who during the course of campaigns carried out at the end of the 90s by the twin rivers caves in zambia (central africa), has found fragments. [4] daughter of nut and geb, sister of nephite, seth and osiris, who she was also married with and father of her son horus. according to the myth, told in the texts of the pyramids and plutarch, tells that isis and osiris with the help of his sister nefti, assembled osiris’s body parts, bringing him back to life. for this reason it was considered a divinity associated with magic and extinction. [5] his name means asset, throne in his hieroglyphic, associated with royalty, heavenly goddess of motherhood and fertility in egyptian mythology. [6] the sign of the gabrielli editori 2004 s. p in cariano vr [7] mircea e. (1984), images and symbols jaca book milano pg 124-126 riscontrabili nella vita quotidiana e risultano essere fondamentali se inseriti in alcuni campi di studio legati al design, al marketing e all’economia in generale. vale a dire quella sfera materiale a cui si rifà la vita umana in contesti antropologici contemporanei, avvalendosi della valenza negativa quanto positiva dei colori per indurre stati emozionali precisi ad esempio ai fini commerciali. notes and bibliography [1] 400.000 di anni fa ha avuto inizio la storia del colore, a quel periodo si deve il primo uso culturale del colore avvenne per la decorazione del corpo. [2] l’uso dell’ocra utilizzata come colorante nelle pitture parietali, nelle opere mobiliari, nelle decorazioni corporali nel paleolitico in europa, durante il medio, si intensifica notevolmente in nei rituali sepolcrali del musteriano recente nel paleolitico superiore il suo uso è legato al colore rosso sangue vita, morte [3] esseri umani appartenenti all’età della pietra media abbiano impiegato pigmenti a scopo rituale almeno 400.000 anni fa: è quanto risulta dagli scavi del prof. l. barham dell’università di liverpool, che nel corso di campagne effettuate alla fine degli anni ’90 presso le caverne di twin rivers, nello zambia (africa centrale) , ha rinvenuto i frammenti. [4] figlia di nut e geb, sorella di nefti, seth ed osiride di cui fu anche sposa e dal quale ebbe horus. secondo il mito, raccontato nei testi delle piramidi e da plutarco nel suo iside ed osiride con l’aiuto della sorella nefti assemblò le parti del corpo di osiride riportandolo alla vita. per questo era considerata una divinità associata alla magia ed all’oltretomba. [5] il suo nome significa aset, trono nel suo geroglifico, associata alla regalità, dea celeste della maternità e della fertilità nella mitologia egizia. [6] il segno dei gabrielli editori 2004 s. p in cariano vr [7] mircea e. (1984) , immagini e simboli jaca book milano pg 124-126 cultura e scienza del colore color culture and science 13 cultura e scienza del colore color culture and science | 10 | 2018 issn 2384-9568 1ute besenecker ute@raumseele.com [corresponding author] 1ted krueger krueger@rpi.edu 2john d. bullough bulloj@rpi.edu 1zachary pearson pearsz@rpi.edu 3robert gerlach rob.gerlach@pantochrome.com 1school of architecture, rensselaer polytechnic institute 2lighting research center, rensselaer polytechnic institute 3pantochrome, gerlach consulting inc. the experience of equivalent luminous colors at architectural scale abstract luminous color used in architectural settings impacts our perception of space and ambiance. with light emitting diode, solid state lighting technology the possibilities of customizing light spectra are manifold, and colored light can be mixed and matched using a variety of different spectral compositions. we conducted several experiments at architectural scale to explore whether stimuli closely matched for chromaticity and light level would produce recognizable differences in visual and visceral qualities. study 1 used qualitative research methods; during the experiment, participants were free to walk from one illuminated space to another to compare conditions close-up and from afar. study 2 used quantitative research methods; participants were situated in a fixed viewing location and responded to a questionnaire that was designed based on the responses from study 1. in study 3 blood pressure was measured in response to all of the lighting conditions. overall, the results showed that subjects perceived differences in the visual qualities of the conditions. the results also showed significant differences in affective qualities and physiological responses between some of the conditions. keywords full-field vision, color perception, architectural-scale experiment, peripheral vision, brightness perception, metamers citation: besenecker u., krueger t., bullough j. d., pearson z. and gerlach r. (2018) ‘the experience of equivalent luminous colors at architectural scale’, cultura e scienza del colore color culture and science journal, 10, pp. 13 20, doi: 10.23738/ccsj.i102018.02 received 07 july 2017; revised 03 november 2018; accepted 03 august 2018 ute besenecker is the technical manager for lighting quality at the designlights consortium. prior work spans product management in led lighting, lighting and human factors research and design practice. she holds a ph.d. in architectural sciences from rensselaer polytechnic institute, as well as master’s degrees from the lighting research center, columbia university, leibnitz universität hannover, and polytechnico di milano. ted krueger is an associate professor of architecture at rensselaer polytechnic institute and a researcher in the center for cognition, communication and culture. he holds a ph.d. in architecture (by design) from rmit, and a professional master of architecture degree from columbia university following an eclectic undergraduate education in the social sciences and the arts at the university of wisconsin-madison. john d. bullough is the director of transportation and safety lighting programs and an adjunct faculty member at the lighting research center, rensselaer polytechnic institute. he is a fellow of the illuminating engineering society and member of the commission internationale de l’éclairage, transportation research board, and the society of automotive engineers. his research interests include human factors, visual performance, and glare. zachary pearson, a summa cum laude graduate of rensselaer polytechnic institute with a bachelor’s in architecture received the 2018 illuminating engineering society merit scholarship, and honorable mention in the international isarch competition. he recently debuted as an artist at the tang museum. an award-winning choreographer and competitive ballroom dancer, zachary will be completing his masters in lighting design in 2019. robert gerlach, president of daylight recovery works in both entertainment technology and addiction recovery. he is recognized as a leader and innovator in solid-state lighting, human color perception, and color management with a track record of business and technology developments. he has a master of business administration focused in entrepreneurial and small business operations from brigham young university. 14 cultura e scienza del colore color culture and science | 10 | 2018 | 13 20 besenecker u., krueger t., bullough j.d., pearson z. and gerlach r. issn 2384-9568 doi: 10.23738/ccsj.i102018.02 1. introduction the use of colored light in architectural design has increased significantly over the past two decades. bold colors, for example, are frequently integrated into lighting for façades and public spaces, and subtle tunable solutions are being tested for retail (e.g., color rendering) and health care (e.g., circadian effects). perceptual experiments suggest that metameric color stimuli, stimuli with the same chromaticity coordinates but different spectral power distributions (wyszecki and stiles, 1982), at the same luminance, might not be identical in perceived brightness (besenecker and bullough, 2016) or saturation (gerlach, 2003), especially when viewed in a full field-ofview including peripheral photoreceptive mechanisms. most color metrics used in practice and application are based upon the central visual field of view (boyce, 2003). in addition, light of different spectral compositions can vary in eliciting nonvisual physiological responses (choi et al., 2011; lockley et al., 2006). the authors of this paper are interested in the architectural relevance of nominally metameric colors when experienced in large-scale conditions with a fullfield of view including peripheral vision. lighting design for theater and music performance has developed a body of knowledge for the creation of sophisticated designs with colored light. in theaters and studios, sevencolor light emitting diode (led) systems are being used increasingly to replace traditional filtered tungsten sources. threeor four-color led sources, as used in many architectural color-changing fixtures, have been judged by design professionals as insufficient to produce the desired color range and quality for theatrical and other performance uses (taylor, 2016). the transition from filtered tungsten sources to multi-emitter led sources comes with the challenge to color match past projects that are being retrofitted (schwendinger, 2016; gerlach, 2016). it also comes with the opportunity to use metameric colors as a new design tool. the technology change also exposed shortcomings for the most common metrics used in industry to measure and match luminous color and light level. practitioners and manufacturers observe limitations in matches made via color and luminance meters, and are often left with developing color and brightness matches by eye (taylor, 2016; gerlach, 2016). in order to investigate the differences in the effects of large-scale colors matched for chromaticity and luminance, we designed dedicated experiments in the 15.25 m x 18.30 m x 10.65 m black box studio space of the experimental media and performing arts center (empac) at rensselaer polytechnic institute (rpi). semi-circular wall surfaces (denoted ‘tubicles’, 2.75 m diameter x 4.25 m height) were built and illuminated with nearly equivalent colors that were mixed using different methods: filtered tungsten, a three-color led system, and a seven-color led system, as well as a video projector. in addition, we closely matched the chromaticity of the colored light using paint pigments illuminated by white led and tungsten light sources. using this ‘apparatus’, we conducted a series of studies with two hue groups, amber and cyan, using hybrid research methods (besenecker and krueger, 2015): a qualitative study (study 1) with 17 participants, followed up by a quantitative protocol (study 2) with 12 participants. the participants experienced the conditions at different vantage points using their full fields of vision. in addition, most of the participants (n=28) also participated in separate sessions (study 3) dedicated to measure blood pressure in response to the lighting conditions. 2. study approach and set-up when viewing nominally equivalent colors with a full field of view, discrepancies in perceived brightness (besenecker and bullough, 2016) and saturation (gerlach, 2003) have been observed. to explore the perceived differences of equivalent colors in architectural-scale spatial settings, we conducted a series of studies. we built several semi-circular viewing chambers (tubicles) in a black-box studio and created seven nearly equivalent color conditions for amber and cyan respectively that were mixed using different methods. figure 1 shows the spatial layout in the planning stages the color conditions for the amber and cyan hue groups were created as follows (with the amber conditions mentioned first, the cyan conditions second): 1. at or ct: a tungsten source with an amber or cyan color filter on white matte paint 2. aled or cled: an amber or cyan led on white matte paint 3. arg or cbg: a red + green led mixture, or blue + green led mixture on white matte paint 4. arl or cir: a red + lime led mixture, or a red + indigo + cyan led mixture on white matte paint 5. ap or cp: a digital light processing (dlp) projector red + green mixture, or blue + green mixture 6. apled or cpled: a white led source on amber or cyan paint 7. apt or cpt: a tungsten source on amber or cyan paint 15 cultura e scienza del colore color culture and science | 10 | 2018 | 13 20 the experience of equivalent luminous colors at architectural scale issn 2384-9568 figure 1 semi-circular viewing chambers (tubicles), size: 2.75 m diameter x 4.25 m height, in a 15.25 m x 18.30 m x 10.56 m black box studio space figure 2 spectral power distributions of amber conditions 2-7 in relation to condition 1 (scaled for relative light level). figure 3 -spectral power distributions of cyan conditions 2-7 in relation to condition 1 (scaled for relative light level). figure 2 (amber) and figure 3 (cyan) show the different spectral power distributions (spds), scaled for relative light level, of conditions 2-7 in relation to condition 1 (filtered tungsten), which was used as a reference. figure 4 shows the chromaticity coordinates for all conditions plotted on the 1964 cie diagram for 10° vision. the cie 1964 color space was chosen as the most commonly used one that includes data for peripheral vision and not only a 2° field of view (e.g. theatre lighting color filter manufacturers often communicate data that way). due to the scale of the set-up and the equipment available, the conditions were not exact metamers; they did not match precisely in their chromaticity (see figure 4). but these are the conditions that 16 cultura e scienza del colore color culture and science | 10 | 2018 | 13 20 besenecker u., krueger t., bullough j.d., pearson z. and gerlach r. issn 2384-9568 doi: 10.23738/ccsj.i102018.02 are found in the field using currently available technologies and so have ecological validity for architecture and design. we were interested in how people would evaluate the conditions and whether consistent patterns in their responses could be observed. we were particularly interested in the following questions: • are there consistent patterns in participants’ comments on perceived differences among conditions? • are the differences consistent with or different from the metrics of chromaticity and luminance? • are there relationships between responses in different categories (e.g. visual and emotional or spatial qualities)? 3. procedures three studies were conducted. 3.1 study 1 study 1 was exploratory and qualitative. seventeen color-normal (ishihara, 1963) participants between the ages of 27 – 82 (mean 50 years) participated, ten males and seven females, with varying degrees of expertise in working with light and color. nine of them work professionally with either light or color: seven as designers and two as photographers. the participants were free to move around as desired; see figure 5. each participant was shown a timed sequence of 13 pairs of illuminated spaces, 2 minutes for each pair, with a 30 second break to reset adaptation of the eyes. they were asked to give any comments and comparisons in response to the color conditions. each participant conducted the study with both hue groups, amber and cyan, separately, one in the morning, one in the afternoon. the order of conditions and hue groups were varied for counterbalancing. figure 4 chromaticity coordinates (cie 1964) for the amber (left) and cyan (right) conditions figure 5 participants evaluating and comparing two amber conditions (left) and two cyan conditions (right) figure 6 participant sitting in the tubicle (left) using a questionnaire (right). 17 cultura e scienza del colore color culture and science | 10 | 2018 | 13 20 the experience of equivalent luminous colors at architectural scale issn 2384-9568 figure 7 participant sitting in the tubicle for blood pressure measurements, amber (left) and cyan (right). all comments, whether written or spoken, were recorded, transcribed and coded into categories: visual qualities (brightness, saturation), emotional qualities (aversion, attraction), and spatial qualities. the results were graphed and produced ranking orders for the different conditions (e.g., bright to dim, saturated to unsaturated). 3.2 study 2 based on the terms used by the participants in study 1 to describe the conditions, we conducted a follow-up study (study 2) two months later using the same lighting conditions. twelve colornormal (ishihara, 1963) participants between the ages of 24 – 65 (mean 43 years), eight males and four females, sat in a fixed location (see figure 6) and evaluated the conditions using a questionnaire. none of the participants had been part of study 1. they had varying degrees of expertise in working with light and color. six of them work professionally with either light or color: two as designers, four as scientific researchers. 3.2 study 3 study 3 was conducted with participants of study 1 and 2 in a separate session, sitting immersed in the condition as illustrated in figure 7. there were twenty-eight participants, all between the ages of 24 – 79 (mean 46 years), with eighteen males and ten females. blood pressure was measured using an arm cuff at the onset (base line) and for each condition (1.5 minutes of exposure). in between the conditions the participants were exposed to 30 seconds of darkness to reset adaptation 4. results study 1 produced a rich variety of comments, such as: “oh! that is very much more cheerful. i don’t know why. it doesn’t look that different, but it seems more cheerful. when you are in it, it feels more like it is difficult to balance. try to stand on one leg. hehehe. this is leathery. i could knit myself up in there though.” some comments revealed individual differences in perception and preference, depending on experience and personality. the below responses of two different participants to the same -exciting or upsettingcondition are an example: participant #16: “(laugh) oh, wow, now that gets me excited. on the right. oh my gosh. that’s a happy color! hah! oh my lord. nice contrast here.” participant #7: “that’s very bright and very light. almost translucent. it’s back to upsetting. a group that’s upsetting. unstringing. it makes me breathe hard.” while individual differences could be observed, there were also reliable average patterns in the study results. for studies 1 and 2, all results were organized in categories of visual qualities (brightness and saturation), emotional qualities (attraction), and spatial qualities (spaciousness). results from both experimental sessions, study 1 and study 2, suggested that people consistently were aware of qualitative differences of the conditions for both hue groups, amber as well as cyan. this held true not only when observers were seated in one location and instructed to fill out a questionnaire (study 2), but also when walking around comparing conditions from different locations (study 1). differences in perceived brightness were distinct and significant, and the brightness perception results were predicted slightly better using a provisional scene brightness model (besenecker and bullough, 2015) than luminance, the industry standard. also, while differences in chromaticity were small, especially for the amber conditions, the differences in perceived saturation were relatively large. focusing on the three led sources only (aled, arg, arl (amber) or cled, cbg, cir (cyan)) suggests that the perceived visual differences in brightness and saturation between the narrowband led condition (amber led (aled) or cyan led (cled) respectively) and the 3-color source led condition (red+green led (arg) or green+blue led (cbg) respectively) were reliable (p<0.05). however, the perceived differences in brightness and saturation between the 7-color source led condition (red+lime led (arl) or red+indigo+cyan led (cir) respectively) and 18 cultura e scienza del colore color culture and science | 10 | 2018 | 13 20 besenecker u., krueger t., bullough j.d., pearson z. and gerlach r. issn 2384-9568 doi: 10.23738/ccsj.i102018.02 the other two led conditions (aled and arg, or cled and cbg respectively) were not. this suggests that when matching luminous colors in spatial environments, options beyond narrowband rgb sources can provide closer perceptual matches. in addition, these can also offer a variety in color rendering properties which might be useful for design applications (taylor, 2016). further to exploring the differences between the luminous color conditions, the studies showed differences between luminous color and illuminated colored paint (illuminated color). the illuminated color conditions were evaluated as similar to the luminous color (colored light on white paint) when viewing them from farther away (study 1), without being immersed or covering the full-field of view. the participants did not notice that it was not the light that was colored. from closeup, immersed in the condition (study 1 and 2), there were, however, differences, as described in the quotes below: participant #10: “initially seems similar, but after looking at paper seems almost grey / more dull and memory of other wall impact is more vivid”. participant #16: “they both seem pretty similar, but the one on the right seems more saturated and luminous. and the one on the left, it feels more integrated with the fabric, and it appears less luminous. and… then when you get up close and it’s the only thing around you it feels pretty saturated. proximity changes some of the effect of the color. they’re quite the similar hue, and now i do realize that that’s actually painted.” the illuminated color retained saturation, while the luminous color conditions desaturated (likely due to chromatic adaptation (fairchild, 2013)). this was especially apparent in the results for the cyan hue group, because chromaticity predicted that the cyan paint condition would look less saturated than the cyan light conditions, which was not the case when being immersed. the above observation suggests that with the increasing use of colored light in architectural environments, more detailed perception studies into full-field chromatic adaptation would be useful to inform the appropriate use of colored light and colored paint in design applications. one of our objectives was to learn about possible relationships between the perceptions of visual, emotional and spatial qualities, and, as well, physiological measures (blood pressure). therefore, after coding all results into such categories and creating interval rankings, we correlated the results. the statistically significant correlations (p<0.05) are summarized in figure 8. as figure 8 shows, for this set of experiments, the perception of brightness was correlated with perceived spatial and emotional qualities for both hue groups, amber and cyan. for example, brighter looking conditions seemed preferred and appeared more spacious than dimmer looking ones. for the cyan condition brightness perception was also correlated with blood pressure (higher brightness was correlated with lower blood pressure). the correlations also suggested that for the amber conditions a higher perceived saturation was evaluated as more attractive and preferred (emotional quality). for the cyan conditions, however, the correlation was reversed: a less saturated appearance was preferred. perceived saturation was also correlated with blood pressure for both hue groups: higher perceived figure 8 correlation between the participant responses (coded into categories) for amber and cyan. 19 cultura e scienza del colore color culture and science | 10 | 2018 | 13 20 the experience of equivalent luminous colors at architectural scale issn 2384-9568 saturation coincided with a higher blood pressure. in addition, blood pressure was correlated with emotional quality (preference) for both, amber and cyan. for the cyan conditions, blood pressure was also correlated with how spacious a condition appeared. perceiving a cyan condition as more spaciousness coincided with a lower blood pressure and was correlated to higher preference (emotional quality). 5. summary for cyan and amber conditions that were matched closely for chromaticity and luminance, participants reported (reliable average trend); these differences were larger than predicted by the industry metrics in common use (luminance, chromaticity). participants also reported differences between the nominally similar conditions in emotional (preference) and spatial qualities (reliable average trend). in addition, there were correlations between visual qualities, spatial, emotional qualities and measured blood pressure. this confirms observations from field practice that the metrics and tools currently used to visually match luminous colors do not provide satisfying perceptual matches when used for large-scale set-ups. furthermore, the results suggest that participants can pick up subtle differences and evaluate nearly equivalent colors differently depending on spectral composition. this could inform design practice when choosing the technologies and tools to implement color into spatial designs. in addition to the average patterns, transcribed qualitative responses and associations substantiated the average trends while also adding information about individual variations between the different participants. ackownledgment the authors thank the experimental media and performing arts center (empac) and the jaffe student production competition, the hass fellowship fund, the light enabled systems and applications research center, the lighting research center and the school of architecture at rensselaer polytechnic institute for their support and contributions, and golden artist colors, etc lighting and controls and philips color kinetics for equipment and advice. we also would like to thank kenneth appleman, meeghan appleman, jonas braasch, tomie hahn, michael oatman, and alicia walf for their input and help, as well as everybody who participated in or helped with the interviews and perception experiments for their invaluable insights. funding this work was supported by the 2015 jaffe student production competition grant, the hass fellowship fund, and contributions by the light enabled systems and applications research center, the lighting research center and the school of architecture at rensselaer polytechnic institute, as well as golden artist colors, etc lighting and controls, and philips color kinetics. conflict of interest the authors state that no actual or potential conflicts of interest exist including financial, personal or other relationships with other people or organizations within three years of beginning the submitted work that could inappropriately influence, or be perceived to influence, their work. bibliography besenecker, u. c. and bullough, j. d. (2017) ‘investigating visual mechanisms underlying scene brightness’, lighting research and technology, 49(1), pp. 16-32. besenecker, u.c., and bullough, j. d. (2015) ‘progress in modelling scene brightness’, in proceedings of 28th cie session, manchester, pp. 1511-1520. besenecker, u.c., and krueger, t. (2015) ‘luminous color in architecture: exploring methodologies for design-relevant research’, enquiry, 12(1), pp. 35-46. boyce, p. (2003) human factors in lighting. second edition. london: taylor & francis. choi, c.-j., kim, k.-s., kim, c.-m., kim, s.-h., and choi, w.s. (2011) ‘reactivity of heart rate variability after exposure to colored lights in healthy adults with symptoms of anxiety and depression’, international journal of psychophysiology, 79(2), pp. 83-88. fairchild, m.d. (2013) color appearance models: john wiley & sons. gerlach, r. (2003) ‘leds to light the theatre’, theatre design and technology, 39(4), pp. 11-23. gerlach, r. (2016) ‘phone conversation with robert gerlach’, in besenecker, u.c. beyond appearances: the experience of luminous color in architecture. ph.d. dissertation. rensselaer polytechnic institute, pp. 180193. ishihara, s. (1963) tests for colour-blindness. 24 plates edition. tokyo: kanehara shuppan co ltd. lockley, s.w., evans, e. e., scheer, f. a. j. l., brainard, g. c., czeisler, c. a., and aeschbach, d. (2006) ‘short-wavelength sensitivity for the direct effects of light on alertness, vigilance, and the waking electroencephalogram in humans’, sleep, 29(2), pp. 161-168. schwendinger, l. (2016) ‘excerpts from a conversation with leni schwendinger’, in besenecker, u.c. beyond 20 cultura e scienza del colore color culture and science | 10 | 2018 | 13 20 besenecker u., krueger t., bullough j.d., pearson z. and gerlach r. issn 2384-9568 doi: 10.23738/ccsj.i102018.02 appearances: the experience of luminous color in architecture. ph.d. dissertation. rensselaer polytechnic institute, pp. 209-212. taylor, c. (2016) ‘phone conversation with clifton taylor’, in besenecker, u.c. beyond appearances: the experience of luminous color in architecture. ph.d. dissertation. rensselaer polytechnic institute, pp. 217-226. wyszecki, g. and stiles, w.s. (1982) color science. second edition. new york: wiley & sons, inc. cultura e scienza del colore color culture and science 53 cultura e scienza del colore color culture and science | 06 | 2016 issn 2384-9568 1letizia bollini letizia.bollini@unimib.it 1dip. di psicologia, università di milano-bicocca topos vs. iris. colour design in web 3.0 mobile app and os: a critical review abstract the it world – i.e. ibm or intel just to mention some of the most popular and elderly companies – seems to have always favoured some colour ranges identified – among all the possible palettes – in blue/cyan variants and grey scale, making of them a sort of chromatic commonplace. this choice apparently perpetuates itself and become even more recurrent in the web 2.0. virtually all brands and interfaces of social networks and sharing platforms first generation elected light blue not to be a differentiating element rather of similarity. from the facebook blue to the twitter or vimeo cyan, colour seems not to be part of the visual language aimed to distinguish the company corporate communication, on one hand, nor the user experience of these platforms, on the other. if the physical impairment of zuckerberg – that made him choose a specific light blue visible also to people with a partial colour blindness – has become almost a urban legend, is not so clear why other brands and entrepreneurs decided a similar chromatic approach, not to say mimetic and plagiarized. conversely, the mobile web 3.0 in its variations – for example ios7 – breaks this pattern opening up to a more wide variability of expression and connotation. but in this re-appropriation of a key component of the visual language does not apparently correspond consistent design awareness. however the lack of constraints – instead of being a challenging opportunity to experiment knowingly with new uses of chromatic codes and meanings – is letting forget the basics of the colour language even in its most basic and semiotic consolidated design guidelines. the paper suggests a critical review by the exemplification and comparison of the major players in the web 3.0 market referring both to the design of colour principles – as part of the graphic culture and the user experience – and to the web accessibility initiative guidelines and to w3c standards. keywords colour design, visual language of colour, colour in web 3.0, colour in social media, colour blindness accessibility citation: bollini l. (2016) ‘topos vs. iris. colour design in web 3.0 mobile app and os: a critical review’, cultura e scienza del colore color culture and science journal, 06, pp. 53-59, doi: 10.23738/ccsj.i62016.05 received 20 january 2015; revised 14 june 2016; accepted 01 july 2016 letizia bollini, artchitect. assistant professor at the department of psychology at the university of milano-bicocca. since 1995 she is dealing with multimodal, interface and interaction design, user experience, visual communication and spatial representation as a researcher, a professor and a pro designer (with her design company extrasmall.it) 54 cultura e scienza del colore color culture and science | 06 | 2016 | 53 59 bollini l. issn 2384-9568 doi: 10.23738/ccsj.i62016.05 1. introduction the it world —i.e. ibm or intel just to mention some of the most popular and elderly companies seems to have always favoured some colour ranges identified —among all the possible palettes— in the spectrum of blue to cyan and grey-scale variants, making of them a sort of chromatic commonplace. this choice apparently perpetuates itself and become even more recurrent in the web 2.0. virtually all brands and interfaces of the first-generation of social networks and sharing platforms elected light blue as tint dominant, using colours not as a differentiating asset, but rather as an element of similarity. from the facebook blue to the twitter or vimeo cyan, colour seems not to be part of the visual language aimed to distinguish the company corporate communication, nor the user experience of these platforms. if the physical impairment of zuckerberg —that made him choose a specific light blue visible also to people with a partial colour blindness— has become almost a urban legend (although confirmed in several interviews), is not so clear why other brands and entrepreneurs decided a similar chromatic approach, not to say mimetic and plagiarized. conversely, the mobile web 3.0 in its variations —for example ios7 or recent material design guideline for android or social platform such as pinterest— breaks this pattern opening up to a more wide variability of expression and connotation. but in this re-appropriation of a key component of the visual language does not apparently correspond consistent design awareness. however the lack of constraints —instead of being a challenging opportunity to experiment knowingly with new uses of chromatic codes and meanings— is letting forget the basics of the colour language even in its most fundamental and semiotic consolidated design guidelines. the paper suggests a critical review by the exemplification and comparison of the major players in the web 3.0 market referring both to the design of colour principles —as part of the graphic culture and the user experience— and to the web specific standards 2. from brand to web: a common chromatic path mainly due to the involvement of one of the most well-known us brand and graphic designer —paul rand— and is remarkable experience, ibm became one of the first companies to set a standard in brand iconography in it field bounding deeply in the corporate culture both the bold and strong slab font and the deep and charming blue. according to the most established attribution of meaning —at least in the western countries— blue represents one of the most serious tint to choose and to use from the colour palette. it has a connection with the concept of calm, relax, deepness, reliability, trust, solidity, security (for a deeper understanding of colours meaning see historical studies: albers [1] and itten [2]; in the field of digital design and internet application: zwick, schmitz and kuehl [3] and the experimental study conducted in 2007 by the author an greco [4]). ibm’s brand has become a milestone and a sort of benchmark in technologies field to look after. intel itself —just to mention the most remarkable entrepreneurship realities— has chosen a bold blue as primary identity colour and magenta as a secondary one to create a huge contrast. fostering from electronic to information technologies, that means growing on a scale of dematerialization, the windows operating system and its graphical user interface is linked to the duality of blue and grey. the same combination —although treated with a graceful balance among cyan, light grey and with— was used both in the web site and in part of the ios 7 action triggers and button [5]. this combination —in the variant of a bright blue tint and a dark neutral grey— was originally used also from the first generation of browsers’ html 1 visualization defaults, that means netscape and successively internet explorer. this widely diffused colour combination has become a common place in which many brands, design patterns, guis’ chromatic palette found a shared language. it seems to work consistently according to the mental model already well known by the users. although just referring to link visualization, jacob nielsen himself recently abandoned the thought that the chromatic pattern applied to the interactive textual elements —electric blue/link, red/active-link and purple/visited-link— should be used permanently as the only possible way to convey a correct affordance to people. a way to admit that colour meaning and mood, if correctly used to highlight or put elements in evidence, are stronger than standard —not designed— solutions inherited by the software culture. in the book web usability [6] he was still strongly recommending to use electric blue and underline to mean ‘interactive link’ in the visual grammar of web graphical interfaces. although other authors strongly disagree with this position —sofia postai [7] and luisa carrada [8] just to mention some of the italian specialists —the assertion of nielsen and the massive use of this design pattern —google abandoned it definitively no more than a month ago in its search engine pages results— tell us how it is still deeply embedded 55 cultura e scienza del colore color culture and science | 06 | 2016 | 53 59 topos vs. iris. colour design in web 3.0 mobile app and os: a critical review. issn 2384-9568 in the web user interface design. 3. the web 2.0 chromatic topos also the second generation of internet —that means the so-called web 2.0— renewed and consolidated this design chromatics topos. almost all the sharing services and social network identify both the brand primary colour and the user interface chromatic pattern in a not so wide range of blue tint. 3.1. facebook and the colour accessibility although facebook wasn’t the first social network established in the ‘00s it has fast become the referring experience in the field. with is undoubted leadership in term of users, power, services and innovation capabilities it is setting most of the standard of the social web, among them also the chromatic palette adopted as a reference for the other first generation of social media design and usability. the choice of the blue tint came out from a personal visual disability of the founder mark zuckerberg: taking an online test he realized that he was red-green colour-blind. blue is facebook’s dominant colour, because – as he said – “blue is the richest colour for me – i can see all of blue.” [9] this remains the leitmotiv of all the many evolution and revolution that facebook improved along the years: it has always been pretty monochromatic since from the beginning (2004) so that the site remains as simple as possible. at the time, a fairly plain site stood in stark contrast to myspace and other previously popular social networks, as remarked by amig agarwal. [10] it is also interesting to notice that facebook abandoned the classical duality of digital palette – a brand/default colour and a contrast one to stress and put evidence on links, buttons and action triggers – to play just with blue the most mute and transparent – according to bonsiepe definition [11] – of the social interfaces. 3.2. linkedin: the professional touch started in parallel with myspace, surpassed by facebook linkedin found its own position in the field of the vertical and specialized social network as the referring point of the professional community a sort of online referenced public curricula as preconized by siegel in the late ‘90s [12]. according to its positioning, vision and mission and to the other unwritten rules of business field, also linkedin has chosen a light blue surrounded by a wide with space and light grey for its brand and gui design. in this case we can interpret both from the mimetic point of view – to be seen serious and professional also in off line and formal work environment – and from the strategic benchmark in the field of social media becoming a neutral aggregator of the daily streaming produced in other platforms (twitter, blogs, etc.) by users. 3.3. vimeo: professional videos on the other hand vimeo made the return journey to the light blue corporate tint, consistently and widely used in the interface of the video channels. its main and heavier competitor is youtube the video streaming platform that represent the second biggest site – after google – in terms of traffic and views. vimeo positioned itself as and streaming aggregator where to present in a selected, well organized and userfriendly framework, professional videos. the bold, dynamic, young and energetic cyan link the platform to the other professional ones – i.e. linkedin – and differentiates it from the chaotic, not well chromatic identified language of youtube – which logo is red and black. the blue meaning is clearly reinforcing the brand declaring the professional vocation of the vlog platform. 3.4. twitter: micro, smart and cyan twitter is probably the most aggressive competitor of facebook, not in terms of users or diffusion – it remains a niche in the field of social networks, but represent the most specialised, innovative and active place where sophisticated digital users, influencers and gurus, meets, dialogs and share high valuable contents – but of language and user experience innovation. in this sense twitter adapts to the chromatic dominant topos, but at the same time is characterized itself by the use of saturated cyan. a colour that maintains the same values of the range of the blue already in the by the other social networks, but in a more dynamic, aggressive and fresh declination. the speed of communication in 140 characters of the microblogging platform is associated with a variation of stronger and sharper colour which makes the interface more vivid, fast and smart. as is clear shown in figure 1 – in which are presented only brand to identify the dominant hue of the entire graphical user interface and its chromatic palette – the dominant colour of the first generation of web 2.0 is blue in its maby various with rare exceptions. on the one hand in combination with cool colours i.e. the range of green as adopted by foursquare and the first version of stumble upon’s brand, on the other hand juxtapose to the magenta in flick’r. the only exception to this is apparently youtube, belonging to the galaxy of services offered by google with matching red and black. 56 cultura e scienza del colore color culture and science | 06 | 2016 | 53 59 bollini l. issn 2384-9568 doi: 10.23738/ccsj.i62016.05 4.the second generation of social media: forcing the colour palette the second generation of social media force explicitly the design patterns also unbalancing the previous blue dominant colour palette towards the warm colours like saturated, bold, hot red. the new ruling seems to express a freer and aggressive communication, on the one hand, but on the other it flattens even more on a unique hue. the chromatic revolution often proceeds in parallel with the re-branding of some services and their positioning and systematization in integrated communication ecosystem. it is the case of google+ that to differentiate itself both the from previous platform launched with little success from google and from the main competitor facebook. g+ opposes to the deep, calm blue a saturated red (100% yellow and magenta) designing a user interface that – in contrast to the neutral and transparent of facebook – is vivid, energetic and hard-hitting. a similar operation is carried out also by stumble upon that leaves behind the brand bichromatic cold and mute, for a one-color red logo more effective and impacting. 4.1. pinterest: red passion point of reference of this second generation is pinterest. it represents an evolution and a mix between flick’r and social interaction models in which many other platforms dynamics converge and merge together. so as facebook is completely played on blue and white to ensure a large neutrality regard to contents, pinterest also plays on the duality of the corporate colour and a secondary hue component. but the effect is significantly different. if the first is likely to result not only in fact monochrome but also mono-tonus, the second one –relying on the significant contrast figure 1 web 2.0 first generation of social media: brand and ui colour. from top to bottom: dominant colour; monochromatic version: blue; polychromatic; monochromatic: other between the red and the neutrality of the layout – plays its identity and user experience on a system where the chromatic contrast creates evidences, hierarchy and focus while ensuring harmony and difference, pleasure and usability. nevertheless the second generation of web 2.0 abandons the blue paradigm and the hegemony of the design patterns introduced by facebook it’s reduced to an even more stereotypical choice of colour. as figure 2 highlights the differences among the brand – not to mention the obvious plagiarism between path and pinterest iconography – are even more reduced. 4.2. the changing language of colour in interaction the experiment proposed by mark hemeon [13] on the buttons of the main social networks and web platforms reveals a deeper aspects of the chromatic language adopted in the interactive aspects of web 2.0. if the first generation of internet adopts a set of colours to indicate the different states of the interaction of a link or a button – i.e. link: blue, active link: red, visited link: purple – in web 2.0, the semantic of colour becomes more complex. the ui project still involves a triad of colours whose meaning is related to the hierarchy of operable actions. a primary colour is chosen to highlight the major action triggers according to the corporate palette and brand hue, another colour —often in contrast with the main one— is used for the sub-actions, important but not essential. the third one is often a neutral or mute one and cover a wider range of interactions both “negative” – for example undo an action – or occasional utilities – such as the settings, or profile customization etc. this tertiary colour is often also used for the effect off or when a link or a button is disabled because you cannot use the function on that page or because it corresponds to the page where you are located. 57 cultura e scienza del colore color culture and science | 06 | 2016 | 53 59 topos vs. iris. colour design in web 3.0 mobile app and os: a critical review. issn 2384-9568 as you can see in figure 3 the major players of the web 2.0 first generation are using the blue as the main colour – i.e. the primary hue of the corporate palette – a second contrasting colour often used as a secondary color in brand identity – the brand’s magenta in flick’r or a complementary yellow in twitter – and a light grey as a neutral identification of utilities. on the other hand, the second generation of social media seems to reduce to a couple of hue – highlight vs neutral – simplifying the chromatic grammar of the graphical interface. 5. mobile os: losing the chromatic grammar the third revolution in the web is represented by the introduction of mobile devices —this means with the debut of iphone in 2007 and of ipad in 2010— and the consequent shift between the world of desktop to the new mobile operating systems and applications. in the transition to mobile operating system apple has become the standard de facto —at least for the android world because windows is figure 2 web 2.0 second generation of social media: brand and ui colour. from top to bottom: dominant colour; monochromatic version: red; polychromatic; monochromatic: other figure 3 an extract of “the button test” conducted by mark hemeon on social media ui taking its own way— to refer to for developing single and commercial applications’ interfaces. the ios7 [4], in particular, is making a wide use of colour both with explicit labels or text explaining the effect of each buttons/action trigger in an interface language that abandoned definitively a mimetic approach to simulate the real world, that means skeuomorphism, 3d and shadows effects and a large use of iconographic symbols. the ios7 seems to use for every system section colour, so for example the calendar uses red, the cyan email and so on. on one hand, this implies to use a different hue for each one, and secondly, that the semiotics generally attributed to colours such as red or green cannot be consistently applied to this interfaces. also the typical triad of internet – blue, red and purple – or web 2.0 – seen in the in hemeon’s experiment – is abandoned in favour of a dual combination – for example red and cyan or red and green – but without applying a steady and consistent way. the result is a chromatic language ambiguous and confusing in several screens where the 58 cultura e scienza del colore color culture and science | 06 | 2016 | 53 59 bollini l. issn 2384-9568 doi: 10.23738/ccsj.i62016.05 same message is presented in different colours without constant reference to a clear and shared semiotics or meaning. so, for example, by comparing the screenshot shown in figures 4 and 5 we see the same button/message “undo” presented both in red – a warning message that i’m cancelling that means an irreversible action – in the first case and in cyan – a much more less alertive message just referring to the reverse action typical to empty a filled form instead of sending it or the abortion of a task – in the second one. at the same time, the button that should be off (figure 4: timer) and then according to the grammar of colours in which the internet has accustomed us to “off” and neutral stands evidenced by the use red applied to the timer icon. furthermore within the same screen (figure 4: set new alarm) 3 buttons with very different functions – cancel, save and delete – are all three red a very strong and alarming colour reserved to prohibitions, irreversible operations and permanent deletion of information. vice versa in figure 5 are the same colour is an action “active” – saving a draft – either “cancel” – a passive one – the operation that allows to continue editing the text. finally in figure 5: new email message you may notice that the button “undo” and “send” are both cyan. the colour design pattern contradicts the basics rules of usability and the mental model that the user already have – embedded in their experience reinforced in many field of figure 4 the use of colours in ios7: timer and alert setting figure 5 the use of colours in ios7: mail; create an email; delete an email 59 cultura e scienza del colore color culture and science | 06 | 2016 | 53 59 topos vs. iris. colour design in web 3.0 mobile app and os: a critical review. issn 2384-9568 experience, not only the web – that to opposite behaviour of an action trigger, generally corresponds also an opposite use of colours or, at least, of visual handling of each elements. 6. conclusions the evolution of the internet brought to encode and evolve a chromatic language that has its roots on the one hand in the classic visual grammar, the other in the specific dynamics of this medium of mass communication. abandone d the narrow range become a sort of a topos of the chromatic colour palette both corporate and for user interface the experiments of the second generation of web 2.0, however, it seems difficult to diversify and find chromatic identity more original. the search becomes even more uncertain and somewhat more confusing – a babel rather than a new found iris – the new frontiers opened by the worlds of the mobile web 3.0. user experience & interface design should probably go back to the deep roots of the language of colour to their culturally established use and to the encoded and conventionally attributed meanings. funding this research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. conflict of interest no financial or personal interest have affected my objectivity, there are no potential conflicts of interest including financial, personal or other relationships with other people or organizations within three years of beginning the submitted work that could inappropriately influence, or be perceived to influence my work. bibliography [1] j. alber, “interaction of color” (revised edition), yale university press, yale, 1975 [2] j. itten, “the art of color: the subjective experience and objective rationale of color”, john wiley & sons inc, 1993 [3] c. zwick, b. schmitz and k. kuehl, “digital colour for internet and other media”, ava, crans-près-céligny, 2003 [4] l. bollini and m. greco, “organizzare presentazioni efficaci”, hoepli, milano, 2008 [5] ios human interface guidelines d e v e l o p e r. a p p l e. c o m / l i b r a r y / i o s / d o c u m e n t a t i o n / userexperience/conceptual/mobilehig/index.html [6] j. nielsen, “designing web usability”, macmillan computer publishing, 2000 [7] s.postai, “siti che funzionano 2.0”, apogeo, milano, 2001 [8] l. carrada, “il mestiere di scrivere”, apogeo, milano, 2008 [9] a. vargas, “facebook co-founder mark zuckerberg opens up”, 20 september 2010, the new yorker www.newyorker.com/reporting/2010/09/20/100920fa_ fact_vargas?printable=true&currentpage=all [10] a. agarwal, “why is facebook so blue in color?”, 21 july 2012 www.labnol.org/internet/why-facebook-bluein-color/17811/ [11] g. bonsiepe, “il ruolo del design”, in g. anceschi (a cura di) “il progetto delle interfacce”, domus academy edizioni, milano, 1993 [12] d. siegel, “futurize your enterprise”, john wiley & sons, 1999 [13] m. hemeon: “the button test”, 10 february 2013 https://medium.com/design-ux/77eb4f9a439d 82 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110110 millennial pink: gender, feminism and marketing. a critical analysis of a color trend kévin bideaux 1 1 laboratoire d’études de genre et sexualité (legs, umr 8238), université paris 8, paris, france. centre français de la couleur, paris, france. bideaux.kevin@gmail.com corresponding author: kévin bideaux (bideaux.kevin@gmail.com) abstract the “millennial pink” refers to a specific range of pink shades which became widely popular towards the end of the year 2015. this trend stormed both the world of fashion and the world of design, and was widely spread through social networks and especially on instagram. the millennial pink was named after its users — a generation of young people born between 1980 and 2000 — the so-called “millennial generation,” whose main feature is their knowledge of new technology and their extensive use of the internet. pink but not really, millennial pink could be described as almost pink. since it is not one color but a wide range of pale pink, the most accurate description would be pinkish beige, or even salmon. above all, millennial pink pretends to bear a meaningful message: this color aims at disassociating itself from the feminine symbolism usually attached to the pink color, and pretending to be a “genderless color.” i intend to analyze this trend through the lens of gender studies, as it appears that millennial pink, far from being genderless, is actually a new form of gendered marketing. indeed, the use of feminist concepts (empowerment, body-positivism) and the use of a strategy based on the association of so-called masculine images with a so-called feminine color allows marketers to seduce the younger generation, seen as consumers sensitive to feminism as well as queer theories. keywords millennial pink, gender marketing, femvertising, queer marketing, color trend, color symbolism received 31 march 2019; revised 22 may 2019; accepted 02 july 2019 citation: bideaux, k. (2019). millennial pink: gender, feminism and marketing. a critical analysis of a color trend. color culture and science journal, 11(1), 82-89. https://doi.org/10.23738/ccsj.110110 millennial pink: gender, feminism and marketing. a critical analysis of a color trend 83 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110110 1. introduction the “millennial pink” refers to a specific range of pink shades which became widely popular towards the end of the year 2015. this color was named after its users, a generation of young people born between 1980 and 2000. the so-called “millenial generation” main feature is their knowledge of new technology and their extensive use of the internet. fashion journalist véronique hyland was the first to assign a name to this color in an article published on the cut website on august 2, 2016. in the article, she describes how this trend stormed both the world of fashion and the world of design, and was widely spread through social networks and especially on instagram (hyland, 2016). this trend first spread through fashion. major brands, from haute-couture (gucci, balenciaga, valentino, etc.) to ready-to-wear (adidas, converse, reebok, etc.) released pink designs. the trend then reached the design and architecture sphere, which was already influenced by the emerging “scandinavian pink” mostly through nordic furniture. surprisingly, the millennial pink became a trend in the gastronomy and cooking world. eventually, pink images of “fooding” got huge on social networks, with an ever-growing amount of rosé pictures and rosé cocktails, beetroots, strawberries, pitayas and other radish dishes. the millennial pink craze even reached tourism, and the australian pink lake since became a very attractive destination for millennials. the millennial pink definitely forms a new approach to pink, as it no longer refers to its popular gendered symbolic inherited from the twentieth century (paoletti, 2012). therefore, it is not a new pink, but it is a subcategory of pink grouping a set of hues, intended to dissociate itself from a so-called feminine archetype that embodies the princess pink, or the barbie pink. fashion journalists have difficulties trying to describe the millennial pink, mostly because it is actually not a color. it is a set of shades of pink, a color chart of pale pink, beige pink and salmon, that i tried to determine from a hundred images collected on the internet (fig. 1). more than a color, the millennial pink is above all an idea. french color historian michel pastoureau says that colors first are a concept, then an idea and finally an intellectual category (pastoureau, 2010). it is a non-feminine pink, a “not-pink pink” (mitchel, 2017), that is located in areas of the color spectrum where it is difficult to describe the hues. these pale hues are thus paired with so called gender-neutral colors, such as whites, beiges, oranges and grays. fig. 1. color chart of millennial pink obtained from the collection of one hundred images answering the keyword “millennial pink” on the internet (google images), september 2017 (© kévin bideaux). millennial pink: gender, feminism and marketing. a critical analysis of a color trend 84 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110110 2. the origins of the trend since millennial pink is more a zeitgeist than an actual object, its “history” is quite hard to map out. to achieve a global understanding, the study of this particular color in itself must be paired with a study of how this trend was formed, and more particularly in its relationship with fashion and design. the internet is the backbone of today’s development of musical and visual micro-trends. the mainstreaming of the « millennial pink » on the internet — and especially on the website tumblr (millennial pink also is sometimes called “tumblr pink”) — could be connected to the growth of the seapunk movement (stuhr-rommereim and mollichi, 2014) as well as the vaporwave (tanner, 2015). these two micro-genres of electronic music framed a visual aesthetic putting pink color as a driving element. but what seems to have definitely launched the millennial pink is its “color of the year” nomination by the most influential trend office: the pantone color institute. since 2000, pantone appoints a “color of the year” based on a multimodal trend analysis. obviously, the “pantone propaganda” bears a strong power over the growth of a trend (lo, 2016), and the nominated color always hits the worlds of fashion, design and graphics, whether immediately or a few months later. unexpectedly, the 2016 winner is not one, but two colors: pantone announced on december 3, 2015 that “rose quartz” and “serenity” (a shade of blue) were both elected colors of the year (fig. 2). fig. 2. “rose quartz” (pantone 13-1520) and “serenity” (pantone 15-3919), elected color of the year 2016 by pantone (© kévin bideaux). beyond their relaxing qualities and the visual contrast that is played between these two tones, it is the pair of colors traditionally gendered that we are dealing with: in the west world, the blue is for boys and the pink is for girls. however, the press release announcing the election of the duo serenity-rose quartz still claimed an overcoming of the sexual dichotomy by the appropriation of its chromatic symbols (pantone, 2015). it is common to believe that fashion is a reflection of societal advances (erner, 2008, p.52), therefore pantone’s pink and blue would echo the social movements towards gender equality, transgender people rights and same-sex marriage. accordingly, they would become the emblem of a younger generation supposedly less inclined to categorization and more opened to gender fluidity. then, rose quartz should be understood as subversive, since it shifted the popular view on pink by splitting with its feminine symbolism to make it the very color of feminism — which was traditionally the violet (habib, 1988) —, of sex equality, and even of the neutral. to do so and in order to achieve a renewal, its association with the world of little girls and princesses must be relinquished. 3. pink, feminism and marketing: when rihanna sells feminism from the very beginning, the millennial pink was associated with the feminine gender and it was very quickly presented as a feminist color that would celebrate the return of a strong femininity — asserted by a traditionally feminine color now presented as a positive value —. pink but not really pink, millennial pink would embody the color of compromise. it is aimed at women who do not want to choose between traditional femininity and radical feminism. the digital revolution has given feminism a worldwide visibility that disclosed phenomena such as street harassment (cochrane, 2013). called “cyber-feminists,” “feminists 2.0,” or “techno-feminists,” the internet campaigns of the youngest generations commonly wave pink as a rallying color. many artists also use pink as a color of femininity in a strong and positive way, like signe pierce, ambivalently yours, lora mathis, etc. it is no coincidence that millennial pink appeared at the same time as “pop feminism” which spread mainly through the singers beyoncé, miley cyrus or nicki minaj (djavadzadeh, 2017). several feminist movements of the 2000s also took up the pink as a symbol of political demands: the gulabi gang in india which campaigned against domestic violence towards women adopted pink sarees to be singled out as members (berthod, 2012) (fig. 3); or the “pussyhats,” an american movement of feminists who demonstrated against the presidential campaign of donald trump, and whose distinctive sign is a pink woolen hat in the form of cat ears (hestir, 2018). these feminist groups are creating a shift in the feminine millennial pink: gender, feminism and marketing. a critical analysis of a color trend 85 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110110 stereotype of pink from gentleness and passivity toward force and rebellion (fig. 4). fig. 3. some women activists of the gulabi gang in bundelkhand, a rural region of india, 2009 (© blindboys.org/flickr). fig. 4. feminist activists at the washington women march against the president donald trump, 2017 (© thirty two/wikimedia commons). the (re)politicization of pink goes hand in hand with the millennial pink trend, and many brands took advantage of the acknowledgment of pink as the color of feminism, even post-feminism. millennial pink is thus used in marketing strategies that since about 2014 have appropriated the feminist struggles to sell products to female consumers, vastly educated to feminist theories. these consumers also do not hesitate to denounce sexism in marketing, and particularly in advertisement. this new strategy is called “femvertising” (contraction of “feminism” and “advertising”), and consists in using feminism to sell, by exploiting the feminist concept of empowerment and body-positivism, by playing with gender stereotypes using a queer aesthetic, or by reclaiming the codes of girl power (milcent, 2017, p.20). therefore, rihanna, who holds strong feminist positions, does not hesitate to appear in pink. in september 2016, she collaborated with the sportswear brand puma for a ready-to-wear collection. almost exclusively pink, the collection “fenty x puma” was based on the millennial pink trend and took the codes of femvertising by offering outfits that combined sports activities with femininity inspired by rococo, using fabrics such as lace or chiffon. rihanna uses here the concept of empowerment developed by feminism to make a marketing surplus for her collection, and for the brand puma: one can be a feminine woman and have so-called male activities or characteristics. the pink initially used in gender marketing to provide a product in a line dedicated to women, becomes here a feminist marker, pushing women to choose the pink product because it is feminine, and no longer to select passively because the products for women are usually pink. however, it should be remembered that the goal of advertisers is to sell their products. it is to seduce consumers that marketers have to borrow the codes of feminism, in an “attention economy” that dominates in contemporary consumerism (franck, 2014). indeed, a societal commitment of a brand can capture this attention and be taken into account in a market strategy (benhamou and diaye, 2016), and pink is an effective communication tool to display such progressiveness. 4. can millennial pink be masculine? when apple released the “rose-gold” color of the iphone 6s in september 2015, this new color challenged the internet, because apple seemed to offer for the first time a smartphone to only one part of the population: women (fig. 5). since colorful objects are strongly associated with the feminine in the west, the men who dare to wear pink clothes or to have pink accessories are still few. this new color is considered too feminine and not manly enough, and very quickly, media and web forums asked themselves the question: can men have a pink iphone? (blanchard, 2015). medias even suggested to rename it “bros’ gold” to reassure the consumer that the purchased product is intended for him (chmielewski and deamicis, 2015). millennial pink: gender, feminism and marketing. a critical analysis of a color trend 86 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110110 fig. 5. iphone 7 “rose gold”, successor of the iphone 6s, 2016 (© macrepairdundee /wikimedia commons). the choice of color in marketing, whether in terms of product, packaging or communication, has a great influence on consumers (kacha, 2009). pink is massively used as a signifier of femininity and is applied on about every marketable product. by targeting a female audience, the pink product keeps, at the same time, the male clientele away. therefore, during the designing conception of the product, the customer’s gender is always addressed, and it is strongly recommended to ban pink if the target audience is a male clientele (bartow, 2008). the nazis used pink during the second world war and its re-appropriation by gay communities make also pink a color of ambiguity and homosexuality (mollard-desfour, 2002). indeed, by becoming the feminine color, pink has become an anti-masculine color, which, when associated with a man or a boy, may cause an alteration of his manhood and create a suspicion of homosexuality. it can also lead to homophobic reactions, sometimes violent (ben-zeev and dennehy, 2014). since the twenty-first century, the contrasts between men and women's clothing are fading, including the gender segmentation of pink for girls (guionnet and neveu, 2009, pp.44-45). according to the executive director of pantone color institute leatrice eisemann, the gender division tends to fade in fashion, which would coincide with the social movements that have been moving toward gender equality since the 1970s. because it splits with the feminine connotations usually associated with pink, the millennial pink is considered as the “new neutral” and perceived by several media as an androgynous color (landry, 2017; hoare, 2017). furthermore, if the media are not slow to take an interest in the appearance of drake with a pink jacket, justin bieber with a pink hoodie, or kanye west who often appears in pink, the extension of millennial pink to the male wardrobe is seen by some media as a feminization of men's fashion, a movement from feminine to masculine often at work when it comes to unisex fashion. it must also be added that we must not confuse sex and sexual wear of clothing, and there are always women's and men's cuts, in addition to unisex cuts (guionnet and neveu, 2009, p.46): if men wear more and more pink, it colors either costumes (fig. 6) or streetwear. 5. the color of the “buzz” it is by combining masculinity and pink that brands are best at attracting attention: the contrast between the association of a feminine color and masculine figures attracts the eye while conveying a queer message of displacement of the stereotypes. for example, german artists eva & adele have made pink the emblematic color of their gender subversion (wuerges, 2016) (fig. 7). this will always be a form of irony that plays on the contrast between the female color and the man who wears it, pink being “still a symbol of femininity and likely to remain so for time” (paoletti, 2012, p.99). this process is not new, and already in 2005 le stade français, the french rugby team, was noticed by choosing to wear pink jerseys. so, when the singer zayn malik appeared on his instagram account with pink hair, it is mainly because he intended to draw attention to him after the release a few days earlier of his new single. still, charli xcx's “boys” video might not have been as successful if it did not show men dressed in pink and doing so-called feminine activities such as washing dishes, participating in pajamas party, or cuddling a stuffed animal. millennial pink: gender, feminism and marketing. a critical analysis of a color trend 87 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110110 fig. 6. the young spanish film-maker eduardo casanova at premios goya, 2017 (© ruben ortega/wikimedia commons). fig. 7. the german artists eva & adele at the venice biennale, 2009 (© arben llapashtica/wikimedia commons). if the trend of the millennial pink took so much scale and evolved so quickly, it is because the idols of millennials, very active on social networks, play with this trend too. they drain around them a stream of media relaying their adherence to the fashion of the moment. any appearance of a star in pink is subject to “buzz,” that is to say, a viral media communication that focuses all the attention, especially on the internet, for a very short period of time. it is a vivid promotional tactic for the media. when they publish their articles, they get the number of views needed on their pages to be adequately paid by advertisements. in the meantime, artists draw attention to themselves and to the products they potentially need to sell. in addition, pink is generating interest in terms of communication: it attracts the eye as much as it arouses curiosity. pink tones attract more attention than more saturated shades or than blue or green shades (lindsey et al., 2010), and in the specific context of the internet, red, purple or pink images, seem to have a better chance of being propagated on pinterest social network (bakhshi and gilbert, 2015). the success of millennial pink lies in its ability to capture the consumer's attention aesthetically, symbolically and politically. a brand like acne was able to own the benefits by adopting a pink powdered visual identity in 2007, before the golden age of the trend color. when walking the street with a tote bag from acne, the customers catch the eye on them, and thus contribute to promote the brand. an increased phenomenon when it comes to male customers, since the chromatic contrast doubles as a symbolic contrast, which not only attracts attention but also spreads the values of a brand that seems to want to break the gender roles. 6. conclusion if pantone ranks colors behind the declared values of gender division, we must keep in mind that fashion has always made gender division a central concern (agacinski, 1998, p.20). it is a product of class division and is primarily intended for elites (simmel, 2013, pp.1013). moreover, if the millennials live in an era that legalized same sex marriage and brought lgbt characters to television (sense 8, transparent, etc.), it is also a generation that has seen the rise of conservatism and even extremism in several countries (usa, brasil, pakistan, etc.). furthermore, debates around gay marriage revealed that homophobia was rooted in different strata of society. pink can therefore also be used with blue by a conservative movement (la manif pour tous, #rosaeazul) to symbolize the importance of gender difference, heterosexuality and nuclear family model (fig. 8). millennial pink: gender, feminism and marketing. a critical analysis of a color trend 88 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110110 fig. 8. the activists of la manif pour tous campaigning against same-sex marriage in paris, 2014. they use the gendered code blue-for-boys/pink-for-girls to defend a traditional family model where parents are heterosexuals (© peter potrowl/wikimedia commons). the recovery of millennial pink and its so-called feminist values by brands is only the development of a new form of gender marketing called “femvertising,” which uses feminists’ concepts to generate profits, proceeding in the same time to the depoliticization of the color (erner, 2008, p.42). furthermore, if brands choose to focus the concept of "gender neutrality" around the only color so strongly associated with the feminine, it is to play precisely with this symbolic moreover, if they share a certain number of common traits, the generation y is in no way a homogeneous whole (dagnaud, 2013, p.8). by standardizing a generation under the same banner, pantone's trend erases the inequalities between individuals and presents gender equality as an achievement reached by all, which is not yet the case. conflict of interest declaration the author states that no actual or potential conflicts of interest exist including financial, personal or other relationships with other people or organizations within three years of beginning the submitted work that could inappropriately influence, or be perceived to influence, their work. funding source declaration this research did not receive any specific grant from funding agencies in the public, commercial, or not-forprofit sector. acknowledgment the author thanks olivier thuillier and marie-dominique gil for helping with the translation and correction of this article. short biography kévin bideaux is a phd candidate in gender studies and art at the university of paris 8, and a visual artist. he conducts research on the 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(2002). le rose : dictionnaire de la couleur, mots et expressions d’aujourd’hui, xxe-xxie siècle. paris: cnrs. pantone (2015). ‘pantone reveals color of the year for 2016: pantone 15-3919 serenity and pantone 13-1520 rose quartz’, pantone. available at: https://www.pantone.com/about/pressreleases/2015/color-of-the-year-2016 (accessed: 2 march 2019). pastoureau, m. (2010). les couleurs de nos souvenirs. paris: le seuil. paoletti, j. b. (2012). pink and blue: telling the boys from the girls in america. bloomington et indianapolis: indiana university press. simmel, g. (2013). philosophie de la mode. paris: allia, 2013. stuhr-rommereim, h. and mollichi, s. (2014). ‘limelight on the butterfly’s wing: seapunk and other structural colorations’, fungiculture. available at: http://www.fufufo.com/post/seapunk/ (accessed: 2 march 2019). tanner, g. (2015). babbling corpses. vaporwave and the commodification of ghosts. alresford: zero books. wuerges, m. (2016). ‘in the studio: eva & adele’, collectors agenda. available at: https://www.collectorsagenda.com/en/in-the-studio/evaadele (accessed: 2 march 2019). cultura e scienza del colore color culture and science 13 cultura e scienza del colore color culture and science | 07 | 2017 issn 2384-9568 anna marotta anna.marotta@polito.it department of architecture and design (dad),politecnico di torino art and colour in the requalification of urban areas and landscapes abstract for contemporary research, peripheral realities, urban voids or dismantled areas and structures represent important opportunities for urban regeneration and redevelopment. the color, through the “color design”, becomes an approach that can achieve remarkable and immediate results with low cost. it is capable of transforming the visual impact of a building, a road, an entire neighbourhood; it orientes and creates harmony through the visual rules and hierarchies, it can recover the identity and image of a place; it can highlights and enhances paths, obstacles, zones, functions, services, or informs through their universally recognizable codes. even today, bruno taut’s idea of improving the quality of life in popular neighborhoods with the creation of polychrome architectures is a reference: the color therefore constitutes the “accessible” decoration even for the most deprived areas. like color, art is a tool for social and urban upbringing. nowaday, art no longer needs to be confined in museums or galleries, but can be placed outdoors in an urban or landscape dimension, becoming public art (made of installations and large sculptures). the contribution, through the study of critically selected and analyzed case studies, tends to verify the validity of this thesis, confirming that art and color constitute both retraining tools and valuable media to promote the recognition of sites and services, attraction poles, urban presence, constituting a real urban communication strategy, without forgetting the role of social and cultural exchanges. of course, the great challenge will be to combine, if possible, the above approaches with the “ways of sustainability”. keywords urban regeneration, participatory design, street art, social sharing. citation: marotta a. (2017) ‘art and colour in the requalification of urban areas and landscapes’, cultura e scienza del colore color culture and science journal, 07, pp. 13-28, doi: 10.23738/ccsj. i72017.02 received 12 january 2017; revised 25 may 2017; accepted 31 may 2017 anna marotta. full professor at the department of architecture and design (dad) of politecnico di torino. she teaches disciplines related to drawing and representation fields, including visual communication, laboratory of drawing and architectural survey. she is part of the teaching staff of the 1st level master in interior, exhibit & retail design and part of the teaching staff of the phd in architectural and landscape heritage. member of uid (unione italiana disegno) scientific committee. since 2012 member of the scientific committee of the gruppo del colore and of the presidential committee of the associazione nazionale colore. italian translation provided: ‘arte e colore nella riqualificazione della città e del paesaggio 14 cultura e scienza del colore color culture and science | 07 | 2017 | 13 28 marotta a. issn 2384-9568 doi: 10.23738/ccsj.i72017.02 1. introduction current research on urban recovery and requalification increasingly deals with conditions found in peripheral areas, the outskirts which are characterised by a lack of elements attesting to the complex multitude of identities, cultures, communities and landscapes within them, and which also are marked by the process of abandonment of industrial areas and large buildings. in this sense, lives in outlying areas, urban empty spaces (or neglected areas and structures) offer an important opportunity for urban requalification, including through “colour planning”. colour is an approach with potentially significant, immediate results and relatively low costs, capable of transforming the visual impact of a building, a street or an entire district. it directs and creates harmony through visual hierarchies, which can be programmed and controlled, even applying different colour theories. this may help transform the identity and image of a place; it has the power to bring out and emphasise routes, obstacles, features and services. it can inform through its own universally recognised codes. although it may seem dated, the reference to bruno taut is still relevant and tangible. along with many of his contemporary architects, he saw the need to create polychrome architecture to improve the quality of life in public housing estates. in 1913, through the creation of facades in hues of red, olive green, blue and ochre, he promoted the idea that colour is an element of “accessible” decoration, even for the more impoverished sections of society: «we no longer want to build, nor see built, buildings lacking colour [which] isn’t as expensive as ornamentation, with its reliefs and cornices, but colour is joie de vivre and [...] for this reason, precisely in an era of distress such as ours [...] we have to fight for colour on all buildings»[1]. 2. physical and mental outskirts: why are there “ugly” quarters? in the collective thought and imagination, the outskirts have an inevitably negative connotation: «outskirts [...] become non-places, areas where the values of the city and public spaces have disappeared, where chances for meetings and friendships rarely or never appear, where there are no employment opportunities, where the presence of public services and the attention administrators pay to the residents’ quality of life is sparse» [2], 1. introduzione l’attuale ricerca sul recupero e sulla riqualificazione urbana affronta sempre più spesso le condizioni delle aree periferiche, caratterizzate dalla mancanza di elementi a testimonianza della complessa moltitudine di identità, culture, comunità e paesaggi al loro interno, e che al contempo rimangono segnate dal processo di dismissione delle aree industriali e dei grandi contenitori. in questo senso, le realtà periferiche, i vuoti urbani (o le aree e le strutture dismesse) rappresentano occasioni importanti di riqualificazione urbana: anche attraverso il “progetto cromatico”. il colore rappresenta un approccio in grado di ottenere risultati notevoli e immediati con costi che possono essere contenuti, capace di trasformare l’impatto visivo di un edificio, di una strada, di un intero quartiere: orienta e crea armonia attraverso gerarchie visive, che possono essere programmate e controllate, anche applicando le teorie del colore. questo può recuperare l’identità e l’immagine di un luogo; può evidenziare e valorizzare percorsi, ostacoli, zone, funzioni, servizi; può informare attraverso i propri codici universalmente riconoscibili. seppur apparentemente datato, appare ancora attuale il riferimento a bruno taut quando come numerosi architetti a lui contemporanei per migliorare la qualità della vita nei quartieri popolari, ritiene necessaria la realizzazione di architetture policrome: nel 1913 promuove, attraverso la realizzazione di facciate colorate di rosso, verde-oliva, blu e ocra, l’idea che il colore costituisca la decorazione “accessibile” anche per i ceti più indigenti: «non vogliamo più costruire, né vedere costruire, edifici privi di colore [che] non è costoso come l’ornamento, con i suoi rilievi e cornici, ma il colore è gioia di vivere e […] per questo, proprio in un’epoca di disagio come la nostra […] noi dobbiamo batterci per il colore in tutti gli edifici» [1]. 2. periferie fisiche e mentali: perchè esistono quartieri “brutti”? nel pensiero e nell’immaginario collettivo la periferia possiede una connotazione inevitabilmente negativa: «le periferie […] diventano i non luoghi, le aree dove sono spariti i valori della città e gli spazi pubblici, dove rare o nulle appaiono le occasioni di incontro e di amicizia, dove mancano le opportunità di lavoro, dove è scarsa la presenza di servizi pubblici e 15 cultura e scienza del colore color culture and science | 07 | 2017 | 13 28 art and colour in the requalification of urban areas and landscapes issn 2384-9568 and «the concept of outskirts is constantly associated to an image of decay, of the lack of infrastructure, of economic and cultural poverty. the picture which emerges is that of a highly problematic area of secondary importance with respect to central, more distinguished zones» [3]. the common connotation of outskirts as border lands or boundary areas is reinforced, at times being true spaces of transition between city and hinterland. it is thus essential to give them back their urban character, that is «to build both urbs and civitas, remembering that often in them, new cultures and new forms of gathering are expressed, quick to evolve and ready to deteriorate, and that more than being a problem for the city, they often are a potential resource» [4]. one of the main concerns regarding current urban policies is therefore the requalification of outskirts which have grown without any apparent criteria since wwii, progressively abandoned to neglect and ghetto-isation with problems of maintenance, road conditions, pollution, the need for a greater number of services, of figure 1 mario sironi, paesaggio urbano (periferia), 1921-22, oil on canvas, 60x77 cm. private collection. from: c. gian ferrari (editor), mario sironi, paesaggi urbani, mazzotta edizioni, milan 1998. nearly one hundred years later, the image is still an expression of the state of abandon which many urban outskirts have been left in. figura 1 1921-22, mario sironi, paesaggio urbano (periferia).olio su tela, cm 60x77. collezione privata. in: c. gian ferrari (a cura di), mario sironi, paesaggi urbani, mazzotta edizioni, milano 1998. a quasi cento anni di distanza, l’immagine vale ancora per esprimere lo stato di incuria in cui sono lasciate molte zone periferiche urbane. l’attenzione degli amministratori per la qualità di vita degli abitanti» [2]; e ancora «il concetto di periferia è comunemente associato ad una immagine di degrado, di mancanza di infrastrutture, di povertà economica e culturale. il quadro che ne emerge è quello di un’area fortemente problematica e di secondaria importanza rispetto alle zone centrali qualificate»[3]. si conferma la comune connotazione delle periferie come aree di bordo, terre di confine, costituendo talvolta veri spazi di transizione tra città e territorio; risulta dunque fondamentale ridare loro caratteristiche urbane, ovvero «costruire insieme urbs e civitas, tenendo conto del fatto che spesso in esse si esprimono nuove culture e nuove forme di aggregazione, rapide nell’evolversi e pronte a degenerare e che oltre ad essere un problema per le città, spesso ne sono una risorsa potenziale» [4]. tra le principali preoccupazioni riguardo le politiche urbane attuali vi è quindi la riqualificazione delle periferie cresciute senza 16 cultura e scienza del colore color culture and science | 07 | 2017 | 13 28 marotta a. issn 2384-9568 doi: 10.23738/ccsj.i72017.02 meeting places of suitable public spaces and greater local identity, which for so long have been overlooked in favour of a rebirth of historic city centres. renzo piano believes it is necessary to take action in the outskirts in order to salvage them, encouraging integration, stratification and the safeguarding of history, attested by these same areas which for no reason must be transformed radically and abruptly through mere demolition: «outskirts are ugly and lacking in quality overall because they weren’t built by the conditions of real lives being lived, which isn’t created just by houses and shops. you need to have everything else, starting from green areas, schools, sports facilities, book stores and gardens» [5]. the “objects” of architecture aren’t enough: it is clear that quality also comes from the social dignity of the inhabitants (the residents), who should be given the highest levels of attention. among the parameters well-suited for the relaunch of the outskirts, “vision”, including its chromatic connotations, is an essential tool in finding or uncovering the identity of a place: requalification is also a valuing of the image and the formal will through actions designed to pursue paradigms which relate to the concept of “sustainable vision” [6]. with respect to the guiding principles just mentioned, we can add others which were popular more recently, such as the removal of aesthetic prejudice in the evaluation of entire historic-artistic periods, or the reconsideration of the relationship between the good (the work of art) and its consumers. all this is complemented by a renewed awareness of the role played by perception (including visual perception) of the work, in relation to the complex vision and perception of its historical significance. according to more up-to-date and “aware” mentalities, works of art are thus no longer seen as a representation, but also an object which is used and perceived (at this point broadly understood), though obviously released from outdated, merely and purely visual positions [7]. defining the word “ugly” means tackling a complex problem: /ugly/ often refers to that which is considered “unpleasant or repulsive, something which creates discomfort; unsuitable, something which goes against morality” and which often, in the history of architecture and art, is associated to the concepts of new and contemporary. for example, just think that when renoir’s nude in the sun was presented in 1875, it was considered “ugly” in addition to offensive. today it is on display at the musée d’orsay. criteri apparenti a partire dal dopoguerra, progressivamente abbandonate al degrado, ghettizzate, con problemi di manutenzione, viabilità, inquinamento, necessità di un maggior numero di servizi, di luoghi di incontro, di spazi pubblici adeguati, di una maggiore identità locale, a lungo trascurate in favore della rinascita del centro storico. renzo piano ritiene necessario un intervento sulle periferie al fine di recuperarle alimentando l’integrazione, la stratificazione, la salvaguardia della storia, testimoniata dalle stesse zone, che per nessuna ragione devono essere trasformate radicalmente e repentinamente attraverso una mera demolizione: «le periferie sono brutte, senza qualità diffusa, perché non ci hanno costruito le condizioni della vera vita vissuta, che non si crea solo con case e negozi. ci vuole tutto il resto, a incominciare dal verde, dalle scuole, dagli impianti sportivi, dalle librerie, dai giardini» [5]. e non bastano solo gli “oggetti” di architettura: è evidente che la qualità è data anche dalla dignità sociale degli abitanti (dei residenti), ai quali va prestata la massima attenzione. fra i parametri atti al rilancio delle periferie la “visione”, compresa la sua connotazione cromatica, si conferma come strumento essenziale nel trovare o ritrovare l’identità dei luoghi: la riqualificazione vive anche come valorizzazione dell’immagine e della volontà formale, attraverso azioni volte a perseguire paradigmi legati al concetto di “visione sostenibile” [6]. rispetto ai principi informatori ora ricordati, possono aggiungersene altri di più recente tendenza, come la rimozione del pregiudizio estetico nella valutazione di interi periodi storico-artistici; o la riconsiderazione del rapporto fra il bene (l’opera d’arte) e i suoi fruitori. tutto ciò va completato dalla rinnovata consapevolezza del ruolo giocato dalla percezione (anche visiva) dell’opera, in relazione alla complessa visione e sensazione della sua storicità. secondo atteggiamenti mentali più aggiornati e consapevoli, l’opera d’arte è vista dunque non più solo come rappresentazione ma anche oggetto di fruizione e di percezione (a questo punto ampiamente intesa), sebbene – com’è ovvio – sganciata da superate posizioni meramente purovisibiliste [7]. definire la parola “brutto” equivale a confrontarsi con una problematica complessa: /brutto/ rimanda comunemente a ciò che viene definito “sgradevole, che non piace, che crea disagio, non adatto, che va contro la morale” spesso, nella storia dell’architettura come dell’arte, associato a concetti di nuovo e contemporaneo: a titolo esemplificativo, 17 cultura e scienza del colore color culture and science | 07 | 2017 | 13 28 art and colour in the requalification of urban areas and landscapes issn 2384-9568 likewise, the eiffel tower, one of the most famous symbols of architecture and engineering in france, and even in europe overall, at the time it was built (1887-1889) aroused intense controversy among the population and members of the parisian artistic-cultural elite. yet, if it’s true that the concept of “ugly” is conditioned by many factors (culture, customs, tradition, historical and environmental context, taste, etc) and if we consider that this possible definition is often associated to the word “discomfort”, then the adjective “ugly” can still be widely used (in architecture and urban planning specifically) without entering into subjective aesthetic judgements, but as objective facts, not due to the lack of information or of culture, but for explicit, real reasons linked to objective criteria of congruity [8]. if we then look to the urban sprawl which salvatore settis speaks of, the need to free the outskirts from the negative connotations which come with it takes on priority importance. «by now, nearly a quarter of the population and production activities are located in areas of urban sprawl, a new distressing form of the italian landscape [...] increasingly similar to a single, disorganised conurbation which grows by some sort of spontaneous propagation. it is thus increasingly true that the urbis form has burst. its indefinite expansion nullifies not only the borders, but also the centre. in the new suburban landscape, the space which remains between the clusters loses its character as a filter and takes on that of a no man’s land» [9]. so, do the outskirts have (or can they have) visual characteristics all of their own? if so, what are they? it seems evidently clear that one of the most relevant missions relates to the connection and interaction between the centre and the outskirts: there is only one city, composed of internal quarters, without any of them being the “best” or the “prettiest”. the disorder and the eyesore of modern neighbourhoods and the outskirts also have one sad characteristic: eternity. the clusters along the periphery leave their mark on the land for a long time, if not indefinitely. only recently has the possibility of demolishing the worst abominations been considered, and often only in the most highly prized panoramic areas. it thus has become urgent, even for the perceptive and psychological wellbeing of those who live in these areas, to think of their requalification, including aesthetically [10]. in reference to the requalification of visual qualities, a useful aid for their planning comes from the so-called “correspondence by analogy”, in which “knowledge” based on shared rules corresponds to the visual component. in this type of visual model, ricordiamo che nudo al sole di renoir quando fu realizzato nel 1875 fu considerato “brutto”, oltre che offensivo: oggi è una delle opere esposte al musée d’orsay; la tour eiffel, uno dei simboli architettonici e ingegneristici più celebri in francia, e più in generale in europa, all’epoca della sua realizzazione (1887-1889) suscitò forti polemiche tra la popolazione e tra i membri dell’élite artistico-culturale parigina. tuttavia, se è vero che il concetto di brutto risulta condizionato da molteplici fattori (cultura, abitudine, tradizione, contesto storico e ambientale, gusto o altri) se si considera che questa possibile definizione viene frequentemente associata alla parola “disagio”, allora l’aggettivo “brutto” può essere ancora largamente utilizzato (in architettura e urbanistica nello specifico), senza entrare in giudizi estetici di merito soggettivo, ma fatti oggettivi, non per mancanza di informazioni o cultura, ma per motivi espliciti e reali, legati a oggettivi criteri di congruenza [8]. se ci si riferisce allo urban sprawl di cui parla salvatore settis, l’esigenza di liberare la periferia dalle connotazioni negative che porta con sé assume una importanza prioritaria: «ormai circa un quarto della popolazione e delle attività produttive sono insediati in aree caratterizzate da urban sprawl, nuova desolante forma del paesaggio italiano […] sempre più simile a una sola, disordinata conurbazione che cresce per una sorta di propagazione spontanea. è dunque sempre più vero che la forma urbis è scoppiata. la sua espansione indefinita ne vanifica non solo i confini, ma anche il centro. nel nuovo paesaggio di suburbi, lo spazio restante tra gli agglomerati perde il carattere di filtro e assume quello di terra di nessuno» [9]. allora, la periferia ha (potrebbe avere) caratteri visivi suoi propri? e quali potrebbero essere? appare evidente che una delle mission più rilevanti riguarda la connessione e interazione fra centro e periferia: la città è una sola, composta al suo interno da quartieri, senza che debbano esisterne di migliori, o di più “belli”. il disordine e la bruttura dei moderni quartieri e delle periferie hanno inoltre una triste caratteristica: l’eternità. gli agglomerati periferici segneranno infatti il territorio per lungo tempo, se non indefinitamente. solo da poco si è considerata la possibilità di demolire i peggiori obbrobri, spesso soltanto nelle zone paesaggistiche di maggior pregio. è quindi diventato urgente, anche per il benessere percettivo e psicologico di chi abita in queste aree, pensare a una loro riqualificazione, anche visiva [10]. in riferimento alla riqualificazione dei caratteri visivi, un utile ausilio per la loro progettazione proviene dalle cosiddette “corrispondenze per analogia”, in cui 18 cultura e scienza del colore color culture and science | 07 | 2017 | 13 28 marotta a. issn 2384-9568 doi: 10.23738/ccsj.i72017.02 the communicative limit, as legrenzi indicates, is the level of knowledge of those who should know how to interpret the model itself, according to conventions which are established and shared as needed: «the secret is in the way the known is translated into the represented» [11]. in this sense, art and colour, operating by their own nature through analogies consolidated in the collective imagination are essential tools for effective communication aimed at requalifying that which exists. and that is true in specific knowledge, distilled even by comparative colour theories [13]. 3. art and colour: tools for urban requalification as pointed out in other fields [12], each time the topic of colour is discussed, phenomenological complexity is brought up again, both in physiological and psycho-sensory terms and in cultural and symbolical terms. similarly, a number of questions continue to arise: what are the criteria, the procedures of the phenomenon of chromatic expression for analysis and planning? and still, in the present, specific context, how can we not renew the same questions in regard to those in the context of the outskirts? and what are the possible ties with the theories (and related practices) which have arisen and matured up to this point? from the theory to the practice, it has been confirmed multiple times that “colour theory” boasts ancient roots which, starting from greek and roman antiquity reaches up to the present day, passing through still-relevant experiences such as the bauhaus and movements influenced by it [13]. today, research on urban recovery and requalification tackles the topic of the conditions in outlying areas which lack elements which can testify to the complex succession of identity, culture, community and landscape, and which recently have undergone the process of dismantling industrial areas. it is precisely in this sense that the outskirts, empty urban lots or decommissioned areas are important opportunities for urban requalification through “colour planning”. if used in an appropriate way, colour can be a tool for requalification, and also a means of recognising services, hubs of attraction, urban participation on various levels, such as a strategy for urban communication. colour is a way to easily give new meaning to architecture: polychromy becomes “decoration” (in every sense, meaning both “an honour” and “ornamentation”) and places the building in a special relationship with the context [14]. dealing with colour means tackling a difficult to manage complexity. it has been highlighted how alla componente visiva corrisponde un “sapere” basato su regole condivise. in questa tipologia di modelli visivi il limite comunicativo – come indica legrenzi – è costituito dal livello di conoscenza proprio di chi deve sapere interpretare il modello stesso, secondo convenzioni di volta in volta stabilite e condivise: «il segreto consiste nel modo di tradurre il conosciuto nel rappresentato» [11]. in questo senso l’arte e il colore, operando per loro stessa natura attraverso analogie consolidate nell’immaginario collettivo, rappresentano strumenti fondamentali per una comunicazione efficace e finalizzata alla riqualificazione dell’esistente. e ciò vale nel sapere specifico, distillato anche dalle teorie comparate del colore [13]. 3. arte e colore: strumenti per la riqualificazione della città come rilevato per altri ambiti [12], puntualmente, ogni volta che si riprende il tema del colore, se ne ripropone la complessità fenomenologica, vuoi in termini fisiologici e psicosensoriali, vuoi in quelli culturali e simbolici. così come si ripresenta la questione: quali i criteri, le procedure del fenomeno espressivo cromatico per l’analisi e il progetto? e ancora, nel presente, specifico contesto come non rinnovare le stesse istanze a proposito di quelle proprie nel contesto delle periferie? e quali i possibili legami con le teorie (e relative prassi) sinora nate e maturate? si è più volte confermato, dalla teoria alla prassi che il “pensiero cromatico” vanta radici antiche le quali, partendo dall’antichità greca e romana giungono fino a noi, passando da esperienze ancora attuali come quella del bauhaus e dei movimenti da questa influenzati [13]. la ricerca sul recupero e sulla riqualificazione urbana affronta oggi il tema delle condizioni delle aree periferiche che mancano di elementi in grado di testimoniare il complesso susseguirsi di identità, culture, comunità e paesaggi, e che hanno recentemente vissuto il processo di dismissione delle aree industriali. proprio in questo senso, le realtà periferiche, i vuoti urbani o le aree dismesse rappresentano occasioni importanti di riqualificazione urbana attraverso il “progetto colore”. se usato in maniera appropriata il colore può essere strumento di riqualificazione ma anche un mezzo per la riconoscibilità dei servizi, poli di attrazione, presenze urbane a vari livelli, come strategia di comunicazione urbana. il colore è uno degli elementi che più facilmente può attribuire un nuovo significato all’architettura: la policromia diventa “decoro” (in tutti i sensi) e pone l’edificio in rapporto 19 cultura e scienza del colore color culture and science | 07 | 2017 | 13 28 art and colour in the requalification of urban areas and landscapes issn 2384-9568 «dealing with colour in this way, that is, keeping it separate from that which generates it, we run the risk of observing only the phenomenal side of things, their surfaces, that which appears immediately in front of our eyes; we thus succumb to the trick of that which our sensory organs present to us, losing sight of the complex reality of things» [15]. an example of how colour is capable of transforming a city, requalifying it and giving it individuality is in tirana, albania [16], which was entirely renewed thanks to the work of mayor and artist edi rama. after years of chaotic building, tirana was reborn from its greyness thanks to a plan set up by the mayor/artist. to mitigate the intense perceptive impact created by soviet-era building complexes in reinforced concrete, rama ordered an artistic intervention of his own design but with the approval of and in close collaboration with the population, which used building facades as canvases, as means of communication in order to minimise social imbalances and improve the quality of life, presenting streets as galleries of artwork and green sculptures. this intervention has kicked off a series of initiatives, such as i love to play, designed to create new public spaces for the community, converting spaces into sports pitches, demolishing illegal buildings, creating a park and new structures, which has led to the complete rebirth of the capital [17]. colour and art, along with more defined, precise and identifiable visual characteristics, bring emotional content which is more difficult to determine but which contributes substantially in the process of involvement and participation in urban regeneration. in some of the most wellknown studies relating to the emotional content of colours, many psychologists (including rorschach, lüscher and frieling) and colour experts (such as faber birren) have analysed the chromatic preferences of individuals to privilegiato con il contesto [14]. trattare di colore equivale ad affrontare una complessità di difficile gestione. è stato messo in luce come «affrontando in questo modo il colore, tenendolo cioè separato da ciò che lo genera, corriamo il rischio di osservare solo l’aspetto fenomenico delle cose, la loro superficie, quello che appare immediatamente al nostro sguardo; incorriamo cioè nell’inganno di ciò che i nostri organi di senso ci presentano, perdendo di fatto la realtà complessa delle cose» [15]. un esempio di come il colore possa avere la capacità di trasformare una città, riqualificandola e donandole individualità è tirana, in albania [16], totalmente rigenerata grazie all’azione del sindaco e artista edi rama. tirana, dopo anni di disordine edilizio, è rinata dal proprio grigiore proprio grazie a un piano del colore indetto dal sindaco/artista, che ha promosso al fine di mitigare il forte impatto percettivo dato dai complessi edilizi in cemento armato di epoca sovietica un intervento artistico fatto di propria mano ma in accordo e collaborazione stretta con la popolazione, che ha visto l’uso delle facciate degli edifici come tele, e mezzi di comunicazione al fine di ridurre gli squilibri sociali e migliorare la qualità della vita, le strade come gallerie di opere e sculture verdi. questo intervento ha dato il via ad una serie di iniziative, come i love to play, progetto con lo scopo di creare nuovi spazi pubblici per la comunità, convertendo spazi di risulta in campi sportivi, demolendo edifici abusivi, realizzando un parco e di nuovi edifici, che hanno portato alla completa rinascita della capitale [17]. il colore e l’arte, unitamente a più definiti precisi e individuabili caratteri visivi, portano con sé contenuti emozionali di più difficile determinazione, ma che contribuiscono sensibilmente nel processo di coinvolgimento e partecipazione proprio della rigenerazione figure 2 a few colourful facades in tirana, from (http://sardarch. wordpress.com/2009/09/24/tiranaarcobaleno-dall%e2%80%99est/). figura 2 alcune facciate colorate a tirana, in (http://sardarch.wordpress. com/2009/09/24/tirana-arcobalenodall%e2%80%99est/) 20 cultura e scienza del colore color culture and science | 07 | 2017 | 13 28 marotta a. issn 2384-9568 doi: 10.23738/ccsj.i72017.02 understand one’s personality and psychological profile, making them true tools for psychological analysis, identifying in colour the translation of recurring symbols and meanings in the generalised definition of each cultural heritage. equal to colour, art (if experienced with awareness and in a “participatory” way) is a tool for social and urban requalification, after having seen an evolution of its understanding, as is true of everything which it is related to it: from the idea of “usability” by the public, of space, of exhibition. currently, to be considered as such, art no longer needs to be confined to museums and galleries, but can be outdoors in an urban environment or a landscape. more specifically, in the urban panorama of the outskirts, it must be consistent with the more complex structures, both functional and visual. today, there is a change in the concept of “art”, in the idea of its use or the ability to be enjoyed by the public, of space, of exhibition. starting in the sixties, art progressively moved out of museums and galleries to appear on streets, squares, buildings, undergrounds, gardens, and public toilets, becoming public art made of installations, large open-air sculptures [18]. thanks to the spread and gradual acceptance of the phenomenon of graffiti, today street art (even if on different qualitative levels) has fully entered into urban art, helping activate often positive effects on the requalification of quarters or simple buildings which are anonymous or even decaying. the city, when understood in this way, becomes the very location for artistic production in all its effects, a laboratory, a canvas, a platform. outskirts are particularly suited to this role. if for central areas the use of urban art has the purpose of attracting tourists, the return of images of the city, the question becomes diverse and more complex when speaking about the outskirts, especially if in a state of disrepair and decay [8]. public investment aimed at promoting urban art can be a first step towards requalification, both social and physical, of the outskirts: “it creates a sense of belonging, revitalises the urban reality, reinforces civic pride, regenerates a community and reduces vandalism” [19]. if one tries to draw a map of the spaces in which public art is most widely spread, places emerge as meeting hubs and locales, or crossroads: interstitial, abandoned places, where art comes to occupy the traumatic story of that which “has remained”. in these forgotten and “prohibited” areas in particular, art can be expressed most purely, in opposition to an urban dystopia made of alienation and disinterest [20]. in the 1980s, bologna and turin were the first cities in italy to invest in the requalification and reuse of the urbana. tra più noti studi relativi il contenuto emozionale dei colori, molti psicologi, tra cui rorschach, lüscher e frieling, e studiosi del colore, come faber birren, analizzano le preferenze cromatiche del singolo individuo per comprenderne la personalità e il profilo psicologico, rendendole dei veri e propri strumenti per la diagnosi psicologica, identificando nel colore la traduzione di simbolismi e significati ricorrenti nell’accezione generalizzata di ciascun patrimonio culturale. al pari del colore, l’arte si conferma – se vissuta consapevolmente e in maniera “partecipata” strumento di riqualificazione sociale e urbana, dopo aver visto una evoluzione della sua concezione, così come di tutto ciò che a essa è correlata: dall’idea di fruibilità da parte di un pubblico, di spazio, di esposizione. attualmente, per essere tale, l’arte non ha più bisogno di essere confinata in musei o gallerie, ma può essere collocata all’aperto in una dimensione urbana o paesaggistica: più specificamente, nel paesaggio urbano di periferia, in coerenza con le più complesse strutture, funzionali e visive. al giorno d’oggi, si rileva una modifica del concetto di arte, dell’idea di fruibilità da parte di un pubblico, di spazio, di esposizione: a partire dagli anni sessanta l’arte si è progressivamente spostata da musei e gallerie per raggiungere strade, piazze, edifici, metropolitane, giardini, bagni pubblici, diventando public art, fatta di installazioni, grandi sculture all’aperto [18]. grazie alla diffusione e progressiva accettazione del fenomeno del graffitismo, oggi la street art (sia pure a diversi livelli qualitativi) è entrata a pieno titolo all’interno dell’arte urbana, contribuendo a innescare effetti spesso positivi sulla riqualificazione di quartieri o semplici edifici anonimi o addirittura degradati. la città, così concepita, costituisce essa stessa luogo di produzione artistica a tutti gli effetti, un laboratorio, una tela, una piattaforma, ed in particolare la periferia si è prestata a questo ruolo; infatti se per le aree centrali l’uso di arte urbana ha lo scopo di attrarre turisti, di ritorno di immagine della città, diversa e più complessa è la questione quando si parla di aree periferiche, in particolar modo se degradate [8].l’investimento pubblico volto a promuovere l’arte urbana può rappresentare il primo passo verso una riqualificazione – sociale, oltre che fisica – delle periferie: «crea senso di appartenenza, rivitalizza la realtà urbana, rafforza l’orgoglio civico, rigenera una comunità, riduce il vandalismo» [19]. se si prova a fare una cartografia degli spazi in cui l’arte pubblica è maggiormente diffusa, emergono luoghi nodali come ritrovi e locali, 21 cultura e scienza del colore color culture and science | 07 | 2017 | 13 28 art and colour in the requalification of urban areas and landscapes issn 2384-9568 peripheral areas through urban art, followed by milan [18]. 4. art and colour: the stars among the brightest stars of contemporary urban art is banksy, an english artist and one of the biggest promoters of street art [21]. his pieces, often messages and representations with immediate features, almost silhouettes, with a critical-satirical and political commentary, are made with the stencil technique. the artist creates dialogue through the urban reality, rejecting any sense of belonging to a gallery, to a movement or social network, precisely with the goal of maintaining the freedom of his art, so much so that it is often called guerrilla art. another example of street art with a high level of ironic content is that of blu, the pseudonym of an artist from bologna, who appeared on the art scene in 1999. at first, his pictorial practice, despite having original stylistic elements from the start, was linked to the use of spray paint, the standard medium of more traditional graffiti writing. around 2001 blu began working in tempera, using extendable paint rollers in order to drastically enlarge the subjects represented and give them greater visibility and communicative impact. his art became so well known that in 2011 england’s the guardian newspaper listed him among one of the ten best street artists active today [8]. the mixing of architectural and figurative elements as a means of communicating is of particular interest, moving towards a tradition of the known, in the representation which is discussed in the abovementioned quote from legrenzi. the work of fabrizio visone, an artist from turin, also has strong communicative value and a knowing use of contrasting colour. visone graduated from the renato cottini fine arts high school and then earned his diploma in painting from the accademia albertina, both in turin. his work is mostly figurative and generally on oppure crocevia; luoghi interstiziali, abbandonati, dove l’arte viene a occupare la traumatica storia di quel che “è rimasto”. particolarmente in queste aree dimenticate e “proibite”, l’arte può esprimersi nel modo più puro, in contrapposizione a una distopia urbana fatta di alienazione e disaffezione [20]. furono bologna e torino, negli anni ottanta del novecento, le prime città in italia ad investire nella riqualificazione e riutilizzazione dei sobborghi tramite l’arte urbana, seguite da milano [18]. 4. arte e colore: i protagonisti fra i maggiori protagonisti dell’arte urbana nella contemporaneità, vi è bansky, artista inglese, uno dei maggiori esponenti della street art [21]. le sue opere messaggi e raffigurazioni dal tratto immediato, quasi silhouette, a sfondo polemico-satirico e politico sono realizzate tramite la tecnica dello stencil. l’artista cerca di dialogare attraverso la realtà urbana, rifiuta ogni appartenenza a gallerie, movimenti o social network, proprio al fine di mantenere libera la propria arte, tanto da far sì che questa sia stata definita guerrilla art. un’ulteriore declinazione della street art ad alto contenuto ironico è data da blu, pseudonimo di un artista bolognese, presente sulla scena artistica dal 1999. inizialmente la sua pratica pittorica, pur esprimendo fin da subito elementi di originalità stilistica, era legata all’uso della bomboletta spray, strumento tipico del writing tradizionale. già a partire dal 2001 le opere di blu iniziano ad essere eseguite con vernici a tempera e con l’uso di rulli montati su bastoni telescopici in modo da ingrandire notevolmente i soggetti raffigurati dandogli maggior visibilità e efficacia comunicativa, tanto che nel 2011 il giornale britannico “the guardian” l’ha segnalato come uno dei dieci migliori street artist oggi attivi [8]. particolarmente significativa risulta la contaminazione fra elementi architettonici e figurativi a per comunicare, verso una traduzione del conosciuto, nel rappresentato di cui parla il figure 3 banksy, the girl letting go of a heart-shaped balloon is one of the artist’s most famous works. from (http://bit.ly/2s4a8od). figura 3 bansky, la bambina che lascia volare un palloncino a forma di cuore è tra le opere più celebri dell’artista. in (http://bit.ly/2s4a8od). 22 cultura e scienza del colore color culture and science | 07 | 2017 | 13 28 marotta a. issn 2384-9568 doi: 10.23738/ccsj.i72017.02 canvas, yet he also paints large-scale murals in which, like in his medusa anamorph, painting and architecture become one, generating an “additional” spatial relationship, capable of creating special visual relationships depending on the position of the observer. beyond italy, the topic of planning with art and colour design, in connection to anamorphic applications, offers interesting solutions for “sustainable” urban requalification. one valid example of this is the work of julian beever, an english artist who splits his time between england, france, belgium, germany, america and australia. his work stands out because it is anamorphic, with compositions which can establish a relationship of direct interaction directed by the observer through the expert combination of colour, light and perspective [30]. his is a possible example to explore further. from the above considerations, just as from the experiences presented, we can see how extremely common the use of architectural figure 4 a blu and os gemeos’ large mural painted in 2010 on a building in lisbon. (http://blublu.org/) figura 4 blu, 2010, blu in collaborazione con os gemeos realizza un grande murales su un palazzo di lisbona. (http://blublu. org/). già citato legrenzi. un artista torinese caratterizzato da una forte valenza comunicativa e da un sapiente utilizzo di contrasti cromatici a questo scopo è fabrizio visone, artista torinese, diplomato presso il liceo artistico “renato cottini” di torino e laureato in pittura presso l’accademia albertina di torino. le sue opere sono soprattutto rappresentazioni figurative, per lo più su tela; ma l’artista realizza anche murales, in cui – come nell’opera medusa anamorph pittura e architettura si compenetrano, generando una spazialità “altra”, capace di creare rapporti visivi privilegiati a seconda della posizione dell’osservatore. in ambito internazionale, il tema del progetto di arte e colore, in connessione con applicazioni di anamorfosi, ha proposto interessanti soluzioni per una riqualificazione urbana “sostenibile”. un valido esempio è rappresentato da julian beever, artista inglese operante tra inghilterra, francia, belgio, germania, america, australia. la particolarità delle sue opere risiede nelle sue figure 5 fabrizio visone, murals at the factory in via foggia, turin, a project for urbe rigenerazione urbana, 2011; murals made for a street art festival in 2011 in campobasso; (www.fabriziovisone. com) figura 5 fabrizio visone, murales realizzato alla fabbrica di via foggia, torino, progetto urbe rigenerazione urbana, 2011 – murales realizzato al street art festival 2011 di campobasso; (www.fabriziovisone. com). 23 cultura e scienza del colore color culture and science | 07 | 2017 | 13 28 art and colour in the requalification of urban areas and landscapes issn 2384-9568 space is today for the purpose of communication. within this vision, appropriated “urban furnishings” become tools to requalify and add character to a space, even making the very space become a work of urban art which can act as a catalyst, no longer a simple decorative element. the work of mount fuji architects studio and knowhow shop la is a good example of the potential of architecture, of urban enhancement and of colour, especially if combined with precise knowledge of visual communication and with an understanding of disciplines which relate to theories about colour. 5. a concept design to revive the falchera quarter in turin in the course of surveys carried out within the “polychromy” group at the polytechnic university of turin, coordinated by the author, we present, at this office, a meta-planning experiment being figura 7 from left to right: julian beever, push the boat out and white water rafting, a few applications of anamorphosis in street art, from (http://www.julianbeever.net) figure 7 da sinistra verso destra: julian beever, push the boat out e white water rafting, alcune applicazioni dell’anamorfosi alla street art, in (http://www.julianbeever.net) figura 8 left: mount fuji architects studio, in flakes. street furniture. towada, from (http:// officinemarcovaldo.blogspot.com/ search/label/arredo%2ourbano); right: knowhow shop la, comb bike rack, roanoke, virginia, (http:// officinemarcovaldo.blogspot.com/ search/label/arredo%2ourbano) figure 8 da sinistra verso destra: mount fuji architects studio. in flakes. street furniture. towada, in (http:// officinemarcovaldo.blogspot.com/ search/label/arredo%20urbano); knowhow shop la, hairy baking, roanoke (http://officinemarcovaldo. b l o g s p o t . c o m / s e a r c h / l a b e l / arredo%20urbano) composizioni anamorfiche, in grado di stabilire un rapporto di interazione diretta da parte degli osservatori attraverso la combinazione consapevole di colore, luce e prospettiva [30]. un possibile esempio da riprendere. dalle considerazioni su esposte – così come dalle esperienze presentate – emerge come sia estremamente in uso oggi utilizzare lo spazio architettonico con finalità comunicative: in questa visione, un appropriato arredo urbano diviene strumento di riqualificazione e caratterizzazione di uno spazio, arrivando a costituire esso stesso un’opera d’arte urbana, in grado di fungere da catalizzatore e non costituendo solo più elemento di decoro. le realizzazioni di mount fuji architects studio e knowhow shop la, esemplificano bene le potenzialità dell’architettura, dell’arredo urbano e del colore, specie se combinati con conoscenze proprie della comunicazione visiva e con saperi disciplinari afferenti alle teorie del colore. figure 6 left: ninja1 and mach505 of truly design, medusa, anamorphic mural made for the factory in via foggia, turin, for the urbe rigenerazione urbana project in 2011, http://www.truly-design.com; right: massimiliano petrone + truly design, mural for a street art festival, campobasso, 2011, http://www. myspace.com/atelierpetrone figura 6 da sinistra verso destra: truly design, medusa, anamorph ninja1 and mach505murales realizzato alla fabbrica di via foggia, torino, progetto urbe rigenerazione urbana, 2011, http://www.trulydesign.com; massimiliano petrone + truly design, murales realizzato per lo street art festival, campobasso, 2011, (http://www.myspace.com/ atelierpetrone). 24 cultura e scienza del colore color culture and science | 07 | 2017 | 13 28 marotta a. issn 2384-9568 doi: 10.23738/ccsj.i72017.02 carried out for the outlying falchera quarter of turin. the neighbourhood arose in the years of the economic boom as a response to the growing need for housing in the regional capital. the same research is included in the graduate thesis by elisa cosso and roberta giaconi, aiming to investigate (through local experiments) the role of art in urban requalification. the theme is particularly rich with points for reflection and potential: as of today, after a complete transformation not just of the concept of what art is but also of everything that is related to it, to be considered as such it is no longer necessary to be confined in a museum. art can be urban, interacting with the environment which surrounds it, and even able to enrich it. in this sense, it has come to light how the falchera quarter has a deep need to be enriched, to find or uncover, including through art and colour, its collective imagination, free from concepts of exclusion and marginalisation, uncertainties which characterised it for quite some time. in other words, the need for one’s neighbourhood to be recognised for other aspects, that it becomes a destination for someone, can be felt. from this premise, a meta-project to revitalise and bring new meaning to a few of the numerous abandoned or neglected spaces was born, interpreting the fact that the contemporary city and contemporary art live side by side already as a chance for requalification. in turin in particular, they “help” each other reciprocally, generating interest, attention and passion, and breathing life into planning and programming, events and transformations. so, why not bring contemporary art into an outlying quarter like falchera? a “virgin” location in some aspects, it could grow, evolve, gain credibility and a new identity, and at that point perhaps falchera would be the subject of new attention, it might go through a figure 9 an example of a potential mural and of a thematic course in falchera nuova. mock ups by roberta giaconi and elisa cosso figura 9 esempio di murales e di percorso a tema a falchera nuova. elaborazioni realizzate da roberta giaconi e elisa cosso 5. un metaprogetto per la rigenerazione del quartiere falchera di torino nell’ambito di indagini svolte all’interno del gruppo “policroma” del politecnico di torino, coordinato dalla scrivente, si presenta in questa sede una sperimentazione metaprogettuale portata avanti per il quartiere periferico falchera di torino, sorto negli anni del boom economico come risposta alla crescente domanda abitativa nel capoluogo. la stessa ricerca è inclusa all’interno di una tesi di laurea a cura di elisa cosso e roberta giaconi, finalizzata a indagare attraverso sperimentazioni in ambito locale il ruolo dell’arte nella riqualificazione urbana. il tema risulta particolarmente ricco di spunti di riflessione e potenzialità: al giorno d’oggi, dopo una totale trasformazione non solo del concetto di arte (ma anche di tutto ciò che ad essa concerne) per essere tale non necessita più di essere confinata in un museo, ma può essere urbana, interagente con l’ambiente in cui si trova, e in grado di arricchirlo. in questo senso, si è rilevato come il quartiere falchera abbia un forte bisogno di essere arricchito, di trovare o ritrovare – anche attraverso l’arte e il colore – un suo immaginario condiviso, scevro dai concetti di esclusione e emarginazione, insicurezza che per lungo tempo lo hanno caratterizzato. si sente, in altri termini, il bisogno che il proprio quartiere venga riconosciuto per altri aspetti, che divenga meta per qualcuno. da questi presupposti è nato un metaprogetto pensato per rivitalizzare e donare significato ad alcuni dei numerosi spazi di risulta o abbandonati del quartiere, interpretando come occasione per la riqualificazione il fatto che città contemporanea e arte contemporanea convivono già, a torino in modo particolare, 25 cultura e scienza del colore color culture and science | 07 | 2017 | 13 28 art and colour in the requalification of urban areas and landscapes issn 2384-9568 new renaissance and be given new colour, even metaphorically: new people, of different colours, in a neighbourhood unlike any other. a colourful district, but also the fulcrum of attention for a growing number of people and services. certainly contemporary art won’t be the only key to resolving the marginal condition of falchera, but it could be a first step (and perhaps the most visible and immediately communicative one) for other, increasingly necessary renewal strategies. hopefully this condition will become reality as soon as possible, as only then will falchera really begin to be there [8]. 6. conclusions in other fields, it has been shown how, even in the landscape and urban scope, it can be useful to refer to colour theories. this is particularly meaningful and full of potential in the requalification of decaying or outlying marginal zones. the knowledgeable critical selection of visual and chromatic models to refer to is an area in which the discipline of design can make significant contributions. within a sodefined context, theories about colour, with the perceptive variants and constants connected to them, can fully be considered a founding pillar in visual culture. previously considered an indispensable tool for intellectual processing, for critical verification and of use in design, such theories continue even today to form an essential corpus for a knowing, aware approach which specialises in chromatic culture [13]. the studies carried out by the “polychromy” research group are going in this direction: the outcome of long, in-depth studies in the field of colour and visual perception conducted by the author, aimed in this case at improving quality of life and humanising public and private places through actions capable of finding (or uncovering) their “humanity”. this contribution, through the close examination of study cases critically selected and analysed, as well as experiments carried out locally, is intended to verify the validity of the above-mentioned thesis. it confirms that art and colour are not just tools for requalification, but also means of expression and participation invaluable to promoting the recognisability of places and services, points of convergence, urban presences on various levels, making up a true strategy for urban communication without forgetting the role of social and cultural exchange [22]. naturally, the biggest challenge will be that of uniting, if possible, the above-mentioned approaches with “methods of sustainable vision”, conceived of in terms of perceptive coherence, especially that of colour. si “aiutano” reciprocamente, suscitando interesse, attenzione, passione, e dando vita a progettazioni e programmazioni, eventi e trasformazioni: dunque, perché non portare l’arte contemporanea in un quartiere periferico come falchera? una location per alcuni aspetti vergine, potrebbe crescere, evolversi, acquistare credibilità e una nuova identità, e allora forse falchera avrebbe nuove attenzioni, vivrebbe una nuova rinascita, si colorerebbe, anche metaforicamente: nuove persone, di diversi colori, in un quartiere diverso dagli altri. un rione colorato, ma anche fulcro di attenzione per un numero crescente di persone e servizi. di certo non sarà solo l’arte contemporanea la chiave per risolvere la condizione di marginalità di falchera, ma potrà costituire un primo passo – forse il più visibile e immediatamente comunicativo – per altre strategie di rinnovamento, sempre più necessarie. ci si deve augurare che questa condizione si possa avverare al più presto. solo in quel momento falchera potrà dire di esserci [8]. 6. conclusioni in altri campi è stato dimostrato come – anche nella dimensione paesaggistica e urbana – potrebbe essere legittimo riferirsi alle teorie del colore: ciò risulta particolarmente significativo e ricco di potenzialità nella riqualificazione di ambiti degradati o marginali. la consapevole selezione critica dei modelli visivi e delle cromie a cui fare riferimento rappresenta un ambito in cui il settore disciplinare del disegno può fornire contributi significativi. all’interno di un contesto così delineato, le teorie del colore – con varianti e invarianti percettive a esse connesse possono considerarsi a pieno titolo come pilastro fondativo nella cultura della visione. considerate in passato come uno strumento indispensabile di elaborazione intellettuale, di verifica critica e d’uso progettuale, si conferma come continuino ancor oggi a formare un corpus fondamentale per un approccio consapevole e specializzante alla cultura cromatica [13]. le ricerche portate avanti dal gruppo di ricerca “policroma” vanno in questa direzione: esito di lunghe e approfondite ricerche nel campo del colore e della percezione visiva portate avanti dalla scrivente, finalizzate in questo caso al miglioramento della qualità della vita e all’umanizzazione dei luoghi pubblici e privati attraverso interventi capaci di trovare – o ritrovare – “l’umanità” degli stessi. il presente contributo, attraverso la disamina di casi studio criticamente selezionati e analizzati, nonché di sperimentazioni portate avanti in ambito locale, ha inteso verificare la validità della tesi suesposta, confermando che arte e colore costituiscono non solo strumenti di riqualificazione, ma anche mezzi di espressione e partecipazione preziosi 26 cultura e scienza del colore color culture and science | 07 | 2017 | 13 28 marotta a. issn 2384-9568 doi: 10.23738/ccsj.i72017.02 funding this research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. conflict of interest the author declares that nothing has affected his objectivity or indipendence in the production of this work. neither the author nor his immediate family member have any financial interest in the people, topics or companies involved by this article. neither the author nor his immediate family member had a professional relationship with the people and companies cited in this article. neither the author nor his immediate family member are involved in a legal dispute with the people and the companies cited in this article. no conflict of interest including financial, personal or other relatiohsjip with other people and organization within three years of beginning the submitted work that could inappropriately influence, or be perceived to influence, this work. bibliography [1] b. taut, die stadt-korone, 1919 (tr. it. la corona della città, con saggio introduttivo di ludovico quaroni, milano, 1973 [2] m. grana, lontani dal centro. gli interventi pubblici nelle periferie, carocci, roma 2009, p. 16 [3] g. mazzocchi, a. villani (a cura di), sulla città oggi. la periferia urbana. ambiente, cultura, sicurezza, franco angeli, milano 2004, p. 79. [4] a. cecchini (a cura di), al centro le periferie. il ruolo degli spazi pubblici e dell’attivazione delle energie sociali in un esperienza didattica per la riqualificazione urbana, milano 2007, p. 28 [5] f. manzitti, renzo piano, l’appello alla città: “smettetela di diffondere il brutto’; in la repubblica-milano, 7 novembre 2008, http://milano.repubblica.it/dettaglio/ renzo-piano-lappello-alla-citta¬smettetela-di-diffondereil-brutto/1541863/2, consultato il 4 ottobre 2011. [6] a. marotta, visione sostenibile (sustainable vision in the conservation of cultural heritage project). in: heritage architecture landesign focus on conservation regeneration innovation. la scuola di pitagora, napoli, 2013. pp. 1210-1219 [7] a. marotta, cultura della visione per conservare e valorizzare: il caso della cittadella di alessandria / culture of vision to preserve and enhance: the case of citadel of alexandria. in: 35° convegno internazionale dei docenti della rappresentazione. patrimoni e siti unesco. memoria, misura e armonia / heritage and unesco sites. memory, measure and harmony, matera, 24-26 ottobre 2013. pp. 615-622 [8] e. cosso, r. giaconi, progettare l’arte in città. la riqualificazione delle periferie attraverso l’arte, tesi di laurea a.a. 2011-2012, relatore prof.ssa anna marotta, per promuovere la riconoscibilità di luoghi e servizi, poli di attrazione, presenze urbane a vari livelli, costituendo una vera e propria strategia di comunicazione urbana, senza dimenticare il ruolo di scambio sociale e culturale [22]. naturalmente, la grande sfida sarà quella di coniugare, se possibile, i suddetti approcci con i “modi della visione sostenibile”, concepita in termini di coerenza percettiva, massimamente cromatica. 27 cultura e scienza del colore color culture and science | 07 | 2017 | 13 28 art and colour in the requalification of urban areas and landscapes issn 2384-9568 politecnico di torino, ii facoltà di architettura. [9] s. settis, paesaggio costituzione cemento — la battaglia per l’ambiente contro il degrado civile, einaudi, torino 2010, p.7 [10] i.romanello,il colore nel costruito nella città e nel paesaggio in http://www.archibio.com/index. p h p ? i d = 1 2 2 5 & f i t = k c o l o r e _ d e l _ c o s t r u i t o _ n e l l a _ citt%e0_e_nel_pae saggio [11]p. legrenzi, prima lezione di scienze cognitive, laterza, roma-bari 2002, p. 64 [12] a. marotta, teoria e prassi del colore tra europa e america latina. in: bossi a. (a cura di), la casa fuori casa, edizioni scientifiche italiane, napoli 2011, pp. 116-125 [13] a. marotta, policroma. dalle teorie comparate al progetto di colore,celid, torino 1999. [14]c. campagnaro, colore in periferia. linee guida meta progettuali per una riqualificazione tecnologica e semantica dell’edilizia popolare, in atti e rassegna tecnicasocietà degli ingegneri e degli architetti in torino, n. 1, gennaio 2005, pp. 12-31 [15] g. bertagna, a. bottoli, e. castelli, c.villa, piano di riqualificazione percettiva: il caso di monza, n: viii conferenza del colore 2012, bologna, 13-14 settembre 2012. p. 383 [16] cfr. m. a. giusti, architettura, urbanistica, design in albania: l’architetto integrale e la cultura italiana del novecento nello scenario attuale, in: sviluppo sostenibile in albania, emal, tirana 2009, pp. 1023-1027 [17]http://sardarch.wordpress.com/2009/09/24/firanaarcobaleno-dall%e2%80%99est/ [18] d. lucchetti, writing : storia, linguaggi, arte nei graffiti di strada, castelvecchi, roma 1999 pp.18, 107 [19]r. comunian, public art e periferia in gran bretagna: tra identità e rigenerazione, in www.culturalab.com, 4 ottobre 2010 [20]e. seo (a cura di), trespass — storia dell’arte urbana non ufficiale, taschen editore, kiiln 2010, pp.188 [21] si fa riferimento all’intervista concessa dall’artista per il film documentario, sulla vita e l’opera di bansky e di altri street-artists, attribuito a banksy stesso, “exit through the gift shop”, usa-regno unito, 2010; si veda video estrapolato dal film in http://www.youtube.com/ watch?v=a0b90yppque&feature=player embedded#!, e sito ufficiale del film: http://www.banksyfilm.com [22] d. busatto, s. taraglio, il colore nel progetto di architettura. colore tra passato e presente. tesi di laurea a.a. 2008-2009, relatore prof.ssa anna marotta, politecnico di torino, ii facoltà di architettura. [23] w. nerdinger (a cura di), bruno taut (1880-1938), electa, milano 2001. [24] m. b. spadolini, i colori di cornigliano. design per lo scenario urbano, alinea, firenze 2011. [25] gruppo boero, recupero e riqualificazione dell’identità delle periferie: dalla metodologia dell’analisi urbana al singolo edificio nel quadro del progetto colore, in http:// www.no.archiworld.it/docs/depliantferrara2011.pdf [26] a. pilz, villaggio olimpico di torino:moderna scultura a colori, in http://www.bau-satz.net/pdf/applica_21-22_06. pdf. 28 cultura e scienza del colore color culture and science | 07 | 2017 | 13 28 marotta a. issn 2384-9568 doi: 10.23738/ccsj.i72017.02 [27] sardarch, tirana, arcobaleno dell’est, in http:// sardarch.wordpress.com/2009/09/24/firana¬arcobalenodall%e2%80%99est/ [28] j. dewey, arte come esperienza, aesthetica, palermo 2010 [29] l. mumford, art and technics, columbia university press, new york 1952 [30] http://www.julianbeever.net/index.php?option=com_ phocagallery&view=category&id=2&itemid=8 cultura e scienza del colore color culture and science cultura e scienza del colore color culture and science | special issue on food color | 05 | 2016 15 issn 2384-9568 1maria luisa musso mlmcolor@arnet.com.ar 1facultad de arquitectura, diseño y urbanismo, universidad de buenos aires colour as a code in food packaging: an argentine case abstract intellectual and emotional aspects of the product’s image raise the concerns about its qualities; concerns about nutrient content, the ingredients, the amount of sugar, salt, fat. the product appearance induces expectations. “expectations govern our attitude to food and the food scene. we deduce from the appearance of the food in front of us whether it will harm us or be good for us”, says john hutchings.(hutchings 2003) the consumer searches for the attributes he considers most suitable according to his internal needs, in the products he wants to buy. it is necessary to define a target segment to propose the product that is effectively closer to the ideal of the buyer and to communicate its benefits. this is why the packaging has a big responsibility. emotions, memory, social patterns, are behavioral areas in which colour plays an important part. there is a message to remember, and the packaging is a message in itself; it helps to guide, motivate and encourage consumers in their purchase decision. it is imperative to choose the potential customer for the message; each target has its language, its expectations. citation: musso m. l. (2016) ‘colour as a code in food packaging: an argentine case’, cultura e scienza del colore color culture and science journal, special issue on food and colour, 05, pp. 15-19, doi: 10.23738/ccsj.i52016.02 received 21 may 2015; revised 16 february 2016; accepted 19 february 2016 cultura e scienza del colore color culture and science | special issue on food color | 05 | 2016 | 15 19 16 musso m. l. issn 2384-9568 doi: 10.23738/ccsj.i52016.02 1. segmentation it is significant to consider two types of segmentation: functional segmentation and psychological one. in the functional segmentation the idea is to group consumers according to the functional advantages the consumer is looking for. when products are addressed to health conscious consumers, the packaging, associated to the product concept, can produce a functional segmentation. packaging has a decisive influence on the consumers perception, and therefore, in the purchasing decision. psychological segmentation is based on the characteristics of the consumer’s social class, their lifestyle, reference models, their personality, involved in the emotional satisfaction they obtain in the purchase. the psychological differential advantages are often more sustainable than the functional. packaging must show specific signs, build confidence as much as unambiguous product identity. 2. changes in consumer consumers, increasingly informed and demanding, have taken the lead. they show new desires, seeking harmony between quality and wellness. in the twenty-first century the will to live in a more human and less frivolous world emerged. banality is being outdated. the importance of healthy living, honesty and revaluation of emotions are values that flourished and increasingly permeate many aspects of life. packaging design is one of them. information and consciousness: accompanying the suitable healthier urban living, many products are incorporating functional values as a vital part of their communication systems. nutritional and functional information are relevant when choosing a brand or a particular variety. 3. visual identification colours are created in our brain as a perceptual tool to facilitate our visual-cognitive and visualemotional functions. colours are more than a physical process: they work as a signs system, a source of information decoding the world around us. in this world, the products we buy every day are present. the consumers develop their opinion about the products they see in less than 90 seconds from their first interaction with them. between 62% and 90% of that assessment is based on the colour of the product. ((institute for color research,color communications, inc) the communicative properties of a color can be defined by two categories: natural associations and psychological or cultural associations. research conducted by the secretariat of the seoul international color expo 2004 documented the following relationships between color and marketing: 92.6 percent said that they put most importance on visual factors when purchasing products. only 5.6 percent said that the physical feel via the sense of touch was most important. hearing and smell each drew 0.9 percent. vision is the primary source for all our experiences. current marketing research has reported that approximately 80% of what we assimilate through the senses, is visual. color addresses one of our basic neurological needs for stimulation. a complex semiotic process enables the understanding of products differentiation on the market. the impact of colour on the decisions about what product to buy is due to the fact that it is a symbol that reflects the image we have of ourselves, our personality. 4. the colour of the product colour is an essential element used as a sign to represent desirables product attributes. consumers respond to the “total product” that also includes their image. successful design requires an awareness of how colors communicate meaning. colour can provide information about the quality of a product and can also show a strong association with certain product categories. green, for instance, is associated with natural products (figure 1). the marketing function of the package includes the location, because the consumer must be able to identify the type of product (dairy desserts, breakfast cereals, detergents, etc.) from a distance in the linear, and also identification, because once located the product the consumer must clearly identify the products they really want to buy within a family or brand. the packaging must show specific signs, the information that helps build confidence in the product and strengthens consumer purchasing decisions. the graphics and colours used in the package must be consistent with the status or image or expectations it wants to satisfy and must serve to identify and locate the product. colour improves readership. colour can be used as a referent code system for the product. colour coding helps to clearly identify the desire product. in package design some actions apply to the expected typology change in order to produce a strong identification with the brand (figure 4). we also find the opposite strategy, which is to favor the association with the category identity. breaking the category code can be a key to differentiate a new product. in spite of the fact that some brands traditionally use green as a strong (figure 2) identifier, green colour is used in associations with the green countryside and healthy products in most countries. cultura e scienza del colore color culture and science | special issue on food color | 05 | 2016 | 15 19 17colour as a code in food packaging: an argentine case issn 2384-9568 green is related to nature, freshness, fertility, peace, hope, humidity, regeneration, growth, relaxation; is calming, curative, and balsamic, in its positive meanings. in many countries is used to identify bio products. in some others, green is also a visual attribute related to low fat; so do pink and light blue (figure 6 and 7). 5. diet or light products important changes in consumption values caused a typological substitution in the colours expected for certain products. the irruption of diet and light products and the explosive growth in value reached by the concept “low calorie” produced an unexpected change in the colour paradigm. the first experiences in colour for diet products focused on white, silver and pastel colours as pink. finally, green, associated with nature, became a strong identifier for this type of products. then, colour is not talking about product attributes but on their feature of being “light” instead. colours meaning can also have a regional value, given by a mixture of cultural interpretations associated with some colours and their historical use. in spain, for instance, light products began to appear in the 80’s proposed as healthy products. begoña hernández salueña, from the department of physics of the public university of navarra, after consulting several dairy companies, says that there is no official code for the colours of the milk pack. the use of colour by type of milk (blue for the whole, green for semi-skimmed and skimmed) has to do with the organization in supermarket shelves and with the communication for consumers. these colours appear having being selected by the first brand that sold these products, followed for the other brands. but several brands have recently decided to break that tradition and begun using colours more for identifying the brand than the (figure 3) category. central dairy asturiana, for example, has decided to use red for whole milk instead of blue and blue for the semi-skimmed and green for the skimmed. pascual, uses dark blue for whole milk; light blue and pink for semiskimmed and skimmed. 6. light products in argentina it is interesting to see how in argentina, green colour has definitely been adopted as a category code, especially in dairy products. the low fat dairy products area at the supermarket is easily recognizable from far away in a green spot. gonzalo petracchi, packaging designer for sancor, says: the green code emerged in the argentine market around the 90s, when the changes from diet products to light ones came out in order to clarify what was being offered to consumers. diet products sought a cleaner and pure image, in association with reduced-calorie diets choosing a colour as blue/cyan. at the beginning of the change, diet and light were virtually synonymous, but light category products wanted to find their own individuality in a codified meaning, an identity charged with emotional values as care and health, without giving up flavor (figure 8). the official argentine food code and that one of mercosur include the requirements for food labeling, in order to give the information that builds confidence, but no rule appears mentioning the use of colour as an identifier. in argentine food code, for instance, food labeling included in chapter xvii-food or dietary regime specifies the words to use, but not colour: food with low lipid content will be labelled with the name of the product and the indication “diet, reduced lipid value” or “diet of low fat” and also may bear the legends “reduced calorie or low calorie”. in spite of in most cases the colour code for whole fat products is blue, red is also used in argentina as in other countries. green is definitively the colour code for low fat and fat free in argentina. some brands are recently incorporated two greens, light green and darker one; to show a different identification for no fat and low fat. there are a few exceptions. nestle use light blue for 0% fat powder milk and sancor have introduced recently pink to identify 0% fat milk. green is the colour of security. it is also the colour of permission green packaging assures us to eat healthy, preventing us from getting fat, with safety, confidence and certainty. big companies of massive consumer products invested heavily in communication to encourage the establishing of an expressive symbolic code. in the last two years, in argentina, this code has widely spread to others categories. (9) celebrating the power of colour as a code in food packaging, i would like to remember what charles riley wrote in his book color codes: “completely mastering color is impossible, but the power it imparts to those who dare to handle it is as profound as that of light itself”. he says also “colour is a third promethean gift, like language and fire”. (riley, 1995) cultura e scienza del colore color culture and science | special issue on food color | 05 | 2016 | 15 19 18 musso m. l. issn 2384-9568 doi: 10.23738/ccsj.i52016.02 figure 1green = natural figure 2green as brand identifier figure 3 spain red-blue=whole/ blue-pink= light figure 4 usa red=whole=fat free=low fat figure 5 germany green=whole/ red=low figure 6 italy blue=whole pink=whole pink=low green=low figure 7 chile blue=whole/ white+blue-blue-green=low fat figure 8 argentina red=whole green=low/ blue=whole green=low figure 9 argentinaothers categories using green as light=low fat 1 2 43 5 6 8 7 9 cultura e scienza del colore color culture and science | special issue on food color | 05 | 2016 | 15 19 19colour as a code in food packaging: an argentine case issn 2384-9568 bibliography caivano, jose l.1998. color and semiotics: a two-way street. color research and application. 390-401 ccicolor institute for color research, color communications, inc codigo alimentario argentino. ley 18.284 18/ 07 /1969. decreto 2126 /1971. alimentos de régimen o dietéticos, actualizado abril 2007. gage, john. 1993. colour and culture. london. thames and hudson ltd. garcía díaz, diego, 2009. los colores en el packaging y la percepción del consumidor. http://www.packaging. enfasis.com/notas/15103 hutchings, john b. 2003. expectations and the food industry. new york. kluwer academic, plenum publishers. isbn 0306472910 mercosur/gmc/resolucion n° 21/02.reglamento técnico mercosur para rotulación de alimentos envasados. morton, jill. 2005. why color matters. research conducted by the secretariat of the seoul international color expo 2004 http://www.colormatters.com/market_whycolor. html pérez carballada ,césar, 2009. usando los colores para vender más. http://www.packaging.enfasis.com/ notas/14715 riley ii, charles a.1995. color codes. hanover. university press of new england. tornquist, jorrit.1999. colore e luce. milan. istituto del colore cultura e scienza del colore color culture and science | special issue on food color | 05 | 2016 20 issn 2384-9568 this page has been intentionally left white cultura e scienza del colore color culture and science 80 cultura e scienza del colore color culture and science | 07 | 2017 | lecca m. and da pos o. issn 2384-9568 1michela lecca lecca@fbk.eu 2osvaldo da pos osvaldo.dapos@unipd.it 1fondazione bruno kessler, center for information and communication technology, technologies of vision, trento, italia; 2università degli studi di padova, italia communications and comments 2015 was the year of nature and food. this theme has been celebrated by the universal exposition (the expo 2015) that has been held in milano, italia. the title of the expo, “feeding the planet, energy for life”, summarizes its main message: promoting a conscious production of food, by encouraging techniques, that ensure simultaneously high quality and environmental sustainability, in order to reduce energy waste and pollution as much as possible. in 2015, the gruppo del colore – associazione italiana colore also celebrated the expo theme by: 1. organizing the 11th colour conference in milano, in order to give to its participants the opportunity to visit the expo; 2. encouraging the submissions to the conference of works focused on the topic “food colour”; 3. dedicating a special issue of this journal to the theme “food colour”; 4. inviting to the conference and awarding the italian cook gualtiero marchesi with the premio colore, as an appreciation for his capability to merge the colors of food and dishes in an unique artwork. in this column, we focus our attention on the topic “food & colour” that is of great interest for all of us, because colorbased food visual inspection allows to decide about the freshness of the food, and food color often unawares influences our food choices. due to its importance in our daily life, this topic has been addressed also before expo 2015, as for instance the interim meeting “color and food – from the farm to the table” organized in october 2010 by the international colour association in argentina. of course, expo 2015 acted as a catalyst for many satellite events. some examples are: the exhibitions “i colori del cibo, i colori dell’arte”, organized by the musei civici di arte antica (“food colors, art colors”, 2015, bologna, italy), “i colori del cibo” by aliaon ryde (“food colors”, 2015, perugia, italy), “intorno al cibo: colori, luoghi, curiosità” (“about food: colors, places, curiosities”, 2016, marina di carrara, italy); the interactive activity organized by the museo internazionale scienza e tecnologia leonardo da vinci to design the food of the future by combing color and flavor (2015, milano, italy); the recent 10th world congress on nutrition and food sciences in osaka, japan (2017). we have opened our column with the sentence “eat a rainbow”, that is one of the many slogans launched by medical and pharmaceutical associations to promote the consumption of fruits and vegetables necessary for healthy living. we all have surely seen posters and brochure reporting the color chart of healthy fruits and vegetables. on this chart, the beneficial properties of fruits and vegetables have been broken down by their color (see figure 1 for an example). red fruits and vegetables are rich of lycopene, ellagic acid, quercetin, and hesperidin. orange and yellow fruits and vegetables contains beta-carotene, zeaxanthin, flavonoids, lycopene, potassium, and vitamin c. green fruits and vegetables are rich of chlorophyll, fiber, lutein, zeaxanthin, calcium, folate, vitamin c, calcium, and beta-carotene. blue and purple fruits and vegetables provide lutein, zeaxanthin, resveratrol, vitamin c, fiber, flavonoids, ellagic acid, and quercetin. white fruits and vegetables include beta-glucans, egcg, eat a rainbow. [from an advertising campaign for healthy living] coloumn 81 cultura e scienza del colore color culture and science | 07 | 2017 | coloumn. communications and comments issn 2384-9568 sdg, and lignans. these nutrients are important to reduce the risk of tumors and to control blood pressure and ldl cholesterol levels. they normalize digestion time, support retinal health and vision, reinforce immune system activity, and fight harmful free-radicals. from the color chart, we deduce that “eating colors” is fundamental for our well-being. the chart shows that colors of fruits and vegetables are related to their nutritional properties. recognizing them helps to select the nutrients we need. we also observe that color is a powerful indicator of the food quality: a red meat is fresh, while a brown one is not. at the same time, a food with too brilliant colors looks artificial, and it is considered to contain colorants possibly dangerous for the health: therefore, a pistachio ice cream with a faded greenish color will be preferred to one with a bright, gaudy color. the relationship between food quality and color is so important that in 1979, switzerland has founded the natural food colours association, an international non-profit association with the mission of acting on behalf of the natural food colour and/or colouring foods industry. nevertheless, the importance of the color as detector of the nutritional characteristics of the food is not the only one link between color and food. the papers published in the journal special issues as well as some works presented at the 11th colour conference investigated the relationships between color and food from different point of views. the issues addressed in these works can be divided in 5 groups: 1. color and marketing: three papers [1], [2], [3] published in the special issue focused on the relevance that color packaging has on the food market. they state that food package is not only a hygienic protection for the aliments, but it is also a marketing tool: package colors represent the aliment contained in, describe its properties, facilitate the visual identification of the product, enhance its desirability also on the basis of emotions and cultural issues. color is a sign that guides the consumer choice. 2. color food and taste perception: two journal papers [4], [5] and one conference work [6] addressed the problem of how color influences the taste perception, also when combined with other sensorial stimuli (e.g. music), and how the taste is perceived by color-blind people. the impact of the colors on the taste has been proved by many experiments that considered not only the color of the food but also the colors of the tablecloths, of the plates and/or of the environment figure 1: a color chart of healthy fruits and vegetables, adapted from http:// www.rawayurveda.com/4974/eat-arainbow-food-color-chart/ 82 cultura e scienza del colore color culture and science | 07 | 2017 | lecca m. and da pos o. issn 2384-9568 where people eat. 3. food coloring: one conference paper [7] addressed the issue of the food coloring, by reporting an activity organized by the fondazione muba museo dei bambini and expo 2015 and tailored to teach the children the differences between natural and artificial food coloring; 4. color food and art: one journal paper [8] and two conference papers [9], [10] focused on the topic “colored food and art”. the journal work examined aesthetic issues in the chinese art of tea, where the color of the tea blend interacts with the glazed, jade chinese pottery (i.e. the celadon) creating new chromatic effects. one conference paper presented a series of dishes inspired by other artworks, like paintings and sculptures. the other one reported on the role of the color in the futuristic cuisine. 5. colored light for plant growing: one journal paper [11] described the importance of the colors in plant growth: the color of the light illuminating a plant is relevant to the development and to the nutritional quality formation of the plant. the paper presented a led based system, able to create lighting conditions ensuring an optimal growth and productivity of the plants, with the final goal of promoting a novel agriculture, including also the new trend of home farming. despite the issues described in the points above have been analyzed independently, they are strictly related to each other. all these work evidence the relevant role of color to food perception. the papers at points 1, 2, 4 and mainly focused on emotional issues relating food and color. the papers of the groups in points 3 and 4 focused on chemical and physical cues of the binomial color & food, but, although the authors do not mention it explicitly, these features can be related again to the emotional/ perceptive issues analyzed by the works in points 1, 2, 4. in fact, the problem of finding good colors for packaging (point 1) is similar to the problem of enhancing visual quality of an aliment by natural and/or artificial coloring (point 3): in both the cases, the aim is to make the product more attractive, desirable, “beautiful to see and to eat”, in one word a synesthetic artwork (points 2 and 4). the lighting system that controls the plant growth and production mentioned at point 5 may also improve the visual appearance of the plant, satisfying (again) the visual sense. to conclude, we invite you to have a look to figure 2 that we have designed to sum up pictorially the main message of expo 2015. this figure collects a set of monochromatic paintings of carl warner, the foodscapes, where food becomes a structural element of our daily life, like home, balloons, islands, animals. “we are what we eat”, said the german philosopher feuerbarch. here the world too is what we eat. in our opinion, these paintings are meaningful: they are not only nice, funny examples of colored food-art, but also an invitation to respect nature, as structural part of us and of our life, like expo 2015 has highlighted. bibliography [1] kyoko hidaka, a comparison of color schemes and images in the package design of sweets in the us and japan. cultura e scienza del colore color culture and science issue 5, special issue on food colour. [2] maria luisa musso, colour as a code in food packaging: an argentine case. cultura e scienza del colore color culture and science issue 5, special issue on food colour. [3] marina mastropietro von rautenkrantz, colour in food packaging strategies and rules. cultura e scienza del colore color culture and science issue 5, special issue on food colour. 83 cultura e scienza del colore color culture and science | 07 | 2017 | coloumn. communications and comments issn 2384-9568 figure 2: twelve paintings of carl warner, along with the color spectrum. these images show the large variety of food colors and they are an example of how food can stimulate the human creativity. “we are what we eat”, said the german philosopher feuerbach. here the world too is what we eat. in our opinion, carl warner’s artworks are very meaningful: they invite to respect nature, as structural part of us and of our life. this is also the message of expo 2015. the titles of warner’s paintings showed here (http://www.carlwarner.com/) are the following: column on left: garlicshire, fishscape 1, lettuce seascape, yellow island, pasta island, banana balloon; column on right: corn candle, broccoli forest, celeri forest, red hot chilli scorpion, pumpkin paradise, candy cottage. [4] paul chambers, marianne patera, trevor cox, a look into cross-modal associations between taste, color and music. cultura e scienza del colore color culture and science issue 5, special issue on food colour. [5] anna poli, food perception without colors, color and music. cultura e scienza del colore color culture and science issue 5, special issue on food colour. 84 cultura e scienza del colore color culture and science | 07 | 2017 | lecca m. and da pos o. issn 2384-9568 [6] giulio bertagna, aldo bottoli, il colore come sfondo per il cibo. in colore e colorimetria, contributi multidisciplinari, vol. xi a, milano, italia, 2015 [7] francesca valan, mangiare con gli occhi. il colore dei cibi: pigmenti e alimenti. in colore e colorimetria, contributi multidisciplinari, vol. xi a, milano, italia, 2015 [8] lucie ling, tea versus celadon: some chromatic interactions. cultura e scienza del colore color culture and science issue 5, special issue on food colour. [9] emanuela orlando, colore e cibo tra arte e natura. in colore e colorimetria, contributi multidisciplinari, vol. xi a, milano, italia, 2015 [10] michela rossi, giampiero mele. the colour is served! synesthesia of the taste and room in futuristic cuisine. in colour and colorimetry – multidisciplinary contributions, vol. xii b, milano, italia, 2015 [11] daria casciani, fulvio musante, maurizio rossi, domestic horticultural centric lighting design. cultura e scienza del colore color culture and science issue 5, special issue on food colour. cultura e scienza del colore color culture and science 39 cultura e scienza del colore color culture and science | 07 | 2017 issn 2384-9568 1fabrizio ivan apollonio fabrizio.apollonio@unibo.it 1andrea ballabeni andrea.ballabeni@unibo.it 1marco gaiani marco.gaiani@unibo.it 1department of architecture, università di bologna highlight and specular reflection removal in photogrammetric techniques applied to architectural heritage 3d modeling abstract in this paper, we present a new technique to remove specular effects from the photogrammetric results in a automatic photogrammetric workflow for architectural heritage (ah) 3d model construction. our solution provides a new reconstruction pipeline completely integrated in the automatic photogrammetric pipeline re-using existing data to arrange new results. the process of acquisition of the images to get the finished 3d model is therefore unique and the process for acquiring and visualizing the correct perceived color is fully integrated with the process of shape capture. overall, the method does not require specific technical knowledge, being therefore relatively easy to use, and it can be used over many different urban settings and contexts. the proposed methodology is a high-level image-processing algorithm. as such, it uses several lower-level methods for its building blocks. we consider these methods as black boxes, and we explain below their input, output and purpose. we demonstrated the efficiency of our method using case study of our work in many cases of the ca 43 km of historical porticoes system in bologna, italy, a superset of the family of ah objects that it belongs to. keywords 3d modelling, structure from motion, automatic photogrammetry, specular removal, image processing, color mapping, reflection component separation citation: apollonio f. i., ballabeni a., gaiani m. (2017) ‘specular reflection removal in the context of sfm techniques for architectural heritage 3d models construction’, cultura e scienza del colore color culture and science journal, 07, pp. 39-57, doi: 10.23738/ccsj.i72017.04 received 18 february 2016; revised 01 june 2017; accepted 02 june 2017 fabrizio ivan apollonio, full professor at university of bologna, dept. of architecture, and phd in survey of the existing built heritage (university of ancona). his main research topics lies on virtual reconstruction, semantic modeling and application in the field of ict to cultural heritage and development of information/cognitive systems aimed to fruition, study and documentation of ch. andrea ballabeni, neuroscientist at heart and computer scientist for trade, he has worked for the largest italian software companies as software developer and project manager during the last decade. he has a phd in neuroscience and a master degree in experimental psychology. he is now research technician and senior software developer at department of architecture – university of bologna. marco gaiani is full professor of architectural representation at the university of bologna and past director of director of the design dept. of the politecnico of milano and dapt of university of bologna. a specialist in 3d computer imaging, modelling and visualization for heritage and archaeology, he was one the first developers/user of laser scanning technology in the cultural heritage field and also developed photogrammetry-related technologies. 40 cultura e scienza del colore color culture and science | 07 | 2017 | 39 57 apollonio f. i., ballabeni a., gaiani m. issn 2384-9568 doi: 10.23738/ccsj.i72017.04 1. introduction in the field of architectural heritage (ah), 3d model construction and visualization, using techniques based on photogrammetric techniques, is increasingly becoming a key approach, ensuring ease of use and efficient results, even for non-professional [1]. significant progress has been recently achieved in the areas of efficient algorithms for scalable image matching [2], large-scale bundle adjustment [3], and in generating dense and wellcalibrated clouds of point as output [4], the core components of the photogrammetric pipeline. as a result, it is nowadays possible to easily reconstruct large scenes from image sequences and at low cost [5]. the topic of ah 3d reconstruction and architectural modeling from images, in particular, has received considerable attention in the last decade [6], and also our research group developed in this area an efficient pipeline based on automatic photogrammetry to integrate accurate shape and color capture, reproduction and visualization using web-based real-time rendering techniques in [7]. an unsolved issue of our pipeline concerns the problems arising from specular reflections effects. the appearance of specular reflections is inevitable in ah urban environment, due to the characteristics of materials existing in real world. these effects typically appear in areas with polished floors (i.e. marble), or in presence of windows or shop windows, determining scattering effects in geometry and incorrect values of diffuse reflectance. specular reflection are critical flaws, affecting image quality and, then, the final results of each photogrammetric pipeline. specifically, dense point clouds generation and faithful color reproduction are task having difficulties if specular reflections exist in the input images. e.g. acquired textures with the presence of highlights produce distinct loses of details. these problems are generally a side effect of the generally shared assumption by computational approaches that scene surfaces are composed of pure diffuse reflection. however, for a wide variety of inhomogeneous materials in real world, the reflection includes both diffuse and specular components. hence, algorithms that are usually based on an ideal lambertian can completely fail when facing the specular reflection. so far, specularity removal methods need to be used in order to improve the photoconsistency based image-to-surface registration as well as for 3d model reconstruction of surfaces with specular reflection component. diffuse and specular reflections are produced by different physical interactions between light and object surfaces. according to the neutral interface reflection model [8], the color of the specular reflection is identical to that of the illumination, while the color of the diffuse reflection is the intrinsic characteristic of the object. with these assumptions, specularity removal can be viewed as the general problem of extracting information contained in an image and transforming it into certain meaningful representation. this representation is able to describe the intrinsic properties of the input image, and it is well known under the name of intrinsic images introduced by [9]. several characteristics of the original input image can be defined as intrinsic images: illumination color and geometry, surface reflectance and geometry and view-point [10]. in our case, the two intrinsic characteristics that must be extracted are the diffuse and the specular reflection components. we reuse the diffuse reflection and we discard the specular one. in this paper, we present a new technique to remove specular effects from the photogrammetric results. our solution provides a new reconstruction pipeline completely integrated in the automatic photogrammetric pipeline reusing existing data to arrange new results. the process of acquisition of the images to get the finished 3d model is therefore unique and the process for acquiring and visualizing the correct perceived color is fully integrated with the process of shape capture. overall, the method does not require specific technical knowledge, being therefore relatively easy to use, and it can be used over many different urban settings and contexts. our processing is semi-automatic and use the photographs employed in the 3d textured model construction using a standard photogrammetric pipeline. from a functional point of view is part of the image pre-processing phase. image pre-processing methods are fundamental to improve the image quality for successful photogrammetric processing. indeed, being the image processing fully automated, the quality of the input images, in terms of radiometric quality as well as network geometry, is fundamental for a successful 3d reconstruction. in detail our solution exploits two existing steps (a) image color balance and exposure compensation, and (b) image denoising introducing a new extrastep (c) image highlight removal. this last is the key step of the pipeline and represents the main novelty. to enable this last new processing, the central idea is the use of sift flow algorithm, a technique based on dense optical flow research started more than 30 years ago with the work of horn and schunck [11]. we refer to publications like [12, 13, 14] for a detailed overview of optical flow methods and the general principles behind it. 41 cultura e scienza del colore color culture and science | 07 | 2017 | 39 57 highlight and specular reflection removal in photogrammetric techniques applied to architectural heritage 3d modeling issn 2384-9568 sift flow technique align two images sharing similar scene characteristics by matching sift descriptors instead of raw pixels. sift flow allows matching densely sampled sift features between two images, while preserving spatial discontinuities [15], to align the images such that a pixel-wise comparison can be made across the input set. gradients with variation across the image set are assumed to belong to the reflected scenes while constant gradients are assumed to belong to the desired background scene. by correctly labeling gradients belonging to reflection or background, the background scene can be separated from the reflection interference. unlike previous approaches that exploit motion, our approach does not make any assumptions regarding the background or reflected scenes geometry, nor requires the reflection to be static. our specular removal technique is based on [16], but further customizations were introduced and finally the technique was integrated in our automatic figure 1 typical problems of the automatic photogrammetry pipeline in presence of specular effects 42 cultura e scienza del colore color culture and science | 07 | 2017 | 39 57 apollonio f. i., ballabeni a., gaiani m. issn 2384-9568 doi: 10.23738/ccsj.i72017.04 photogrammetric pipeline (figure 2). we tested our method using as case study example from a building with arcades in bologna, a superset of our field of interest because it presents all the problems to which we want give solution. 2. problem characterization & related works figure 3 shows images taken under the porch of a building. in these images, we can see two of the most typical and frequent problems that appear in real-world 3d shape and color capture of urban systems related to specular reflections problems: a. polished pavements presenting highlights caused by different light sources; b. a scene image behind a glass pane. this is the case of ‘shop window’, where one takes a photograph of an object behind a window. the glass will produce an unwanted layer of reflection in the final image. the reflection from the glass interferes with the view of the interior of the shop behind the shield. in the determination of the diffuse reflection surfaces, traditionally these two phenomena are treated as different problems, one known as specular removal and the second as layers separation. in this paper, we present a technique that aims to model the two phenomena as two sides of the same coin. in our approach, specular and diffuse reflections are assimilated to different layers. in this way, the two problems are brought back to the solution of a single problem known as separation layers, where the captured image is a linear combination of a reflection layer and the desired background scene, , as follows: the goal of reflection removal is to separate ib and ir from an input image i as shown in figure 10. three reasons led to this choice: the approach allows the development of a solution completely integrated in the existing pipeline, easy to implement, and completely automatic; the histogram of the tonal distribution of images with specular effects (see figure 4) does not show the typical behavior of images with highlights where data appears on the right side. for this reason, the results obtained through image processing techniques, or acquiring high dynamic range (hdr) images, in the elimination of specular reflections, are unsatisfactory; recently, a great effort of computer vision community was devoted to the pro-gress of efficient techniques of layer separation. separating illuminant and re-flection is a well-known problem as demonstrated by marc ebner works [17]. several solutions well fit the boundaries of our problems and establish a solid ground on which to develop a specific appropriate solution. in [18] is presented a complete survey of specular removal techniques, with a useful classification to select a proper method for a specific application. the survey classi-fies methods for separating reflection components into two categories by the number of images used: multi-image or single-image methods. the first category uses multiple images taken under specific conditions (e.g. view-point, lighting direction, etc.) and benefits from the fact that for varying viewing directions, the diffuse and specular reflections behave differently. the techniques are based on histogram methods [19], high-low frequency separation [20], multi-baseline-stereo [21], deriving intrinsic images from image sequences with illumination changes [22], color and polarization methods [23] and multi-flash methods [24]. all these figure 2 our automatic photogrammetry pipeline with the specular removal phase on orange background. (1) 43 cultura e scienza del colore color culture and science | 07 | 2017 | 39 57 highlight and specular reflection removal in photogrammetric techniques applied to architectural heritage 3d modeling issn 2384-9568 approaches can be further categorized as local or global depending on how the information is used. highlight removal using a single image is generally much more challenging. the singleimage approaches are based on using color reflection model [25], 2d diagram approach [26], use of specular-free image [27], partial differential equation (pde) approach [28], use of color information and classifier [29], separation of highlight reflections on textured surfaces [30], fresnel methods [31]. in the single-image category, there can be further two categories aiming to identify and separate diffuse color pixels: neighborhood analysis, color space analysis. in case of first category, neighborhood pixels are examined to infer the diffuse information usually by propagating from outside the highlight towards the inside. however, discontinuities in surface colors can make difficult for diffuse information to be accurately transferred [30]. the second category is based on color distributions to distinguish between diffuse and specular components. however, many factors such as image noise or color blending at edges can cause cluttering in color space, which can impair such approaches. as mentioned earlier, the problem is highly ill-posed, therefore these approaches are not free from limitations. for example, in [25] color clustering is very sensitive to noise. polarization figure 3 typical reflection problems in the urban context: shop windows and specular reflections on the floor. figure 4 – figure 3 images histogram. methods like [23] are, at the moment, very promising tools also in our field of application [32], but this paper would like to present a different technique. polarimetric techniques, in effect, require a rotating polarization filter in front of the main capture camera. however, this aspect of capture can be automated, even on a single camera, and excellent data quality. the method proposed in [30] uses color segmentation and polarization filter to remove specular effect retaining geometrical information but the color value is shifted. the method in [23] uses pixel level dichromatic reflection model, however, both this and [31] needs an estimation of illuminant source. following [18] consideration and experimentation results, and a series of tests carried out by us to verify the suitability of specific algorithms to our cases, we could state that although the currently available methods achieve good component separation results, they are limited by the conditions of their applicability. in particular, most of the techniques rely on a specific reflection model and assume that the specular reflectance varies insignificantly with wavelength, which means that its color is essentially that of the light source. this assumption, together with their sensitivity to the noise, reduces the range of applications where these methods can be used. furthermore, most part of these algorithms presents strong light requirement. unfortunately, we are in the case table 2 mean scores and standard deviations of the 116 participants with regard to the board “shot” table 3 mean scores and standard deviations of the 116 participants with regard to the board “bench” 44 cultura e scienza del colore color culture and science | 07 | 2017 | 39 57 apollonio f. i., ballabeni a., gaiani m. issn 2384-9568 doi: 10.23738/ccsj.i72017.04 of uncontrolled light, with materials existing in real world, as well as areas with polished floors (i.e. marble), or in presence of windows or shop windows, that limits a lot the number of solution available. finally, the number of effects that these algorithms are able to manage are limited compared to the complexity of the interactions in the real world. mainly, specular regions are generally composed of a core part and extended specular region. the core part has lost information while extended region has partial image information. most of the work available in literature address the removal of a single specular region, however, the removal of both regions individually retaining maximum possible information is not properly discussed especially for large specular regions. this last problem appears to be crucial in our case. effective solutions to mitigate it are essentially based on manual segmentation, a long, tedious and an easily error-prone process. from the point of view of the algorithm we focused, initially, on single images techniques, based on shafer [33] dichromatic reflection model, starting from specular-free image techniques [30, 34, 35]. these methods are based on the idea of initially generating a pseudo-diffuse component image. this provides a partial separation of the specular component, which is later used to complete the reflection component separation of the original image. the pseudo-diffuse component image is called specular-free image because it is essentially a specularity invariant representation of the input image. we tried also, remaining in the field of single-images and di-chromatic reflection model techniques, pde-based which iteratively erodes the specular channel in the suv color space [28], error analysis of chromaticity and appropriate selection of body color for each pixel [35], bilateral filtering [36], and intensity ratio [37] methods. figure 5 shows some of results obtained using these techniques. we experimented both default parameters and different values to better fit our case study. we could see that the results were completely unsatisfying. a more general approach is introduced in [38] to extract automatically two layers from an image where one layer is smoother than the other. this problem arises not only in reflection removal but also in intrinsic image decomposition. authors introduce a strategy that regularizes the gradients of the two layers such that one has a long tail distribution and the other a short tail distribution. they formulate the problem in a probabilistic framework and describe an optimization scheme to solve this regularization figure 5 results of single images techniques of specular removal, based on dichromatic reflection model. all the algorithms are tested on the original configuration of values. images represent the diffuse component. 45 cultura e scienza del colore color culture and science | 07 | 2017 | 39 57 highlight and specular reflection removal in photogrammetric techniques applied to architectural heritage 3d modeling issn 2384-9568 with only a few iterations. a challenging issue is that if the assumption that the two layer have different smoothness is violated, the methods will fail to correctly separate the layers. figure 6 shows that this failure appears systematically in our case. we tried to enhance the techniques based on the use of a single image introducing a preprocessing where the image is automatically segmented to better find the highlighted area. in a second step previous illustrated techniques are used to remove the specular reflections, restoring the apparent color. we focused on color image segmentation techniques since more utilizable than gray scale image segmentation because of their capability to enhance the image analysis process thereby improving the segmentation result. in color image segmentation, firstly choosing a proper color space is an important issue [39]. lab and hsv are the two most frequently chosen color spaces. following results of [40] we have chosen lab color space. [41] provides an excellent reference for our work describing accurately color image segmentation techniques, and giving a classification useful to correctly analyze and implement segmentation algorithm in an automatic workflow. as in the context of color imagery, segmentation is an ill-defined problem with no perfect solution, we experimented techniques from both the sides of the classification purposed by [36]: • spatially blind methods • spatially guided methods. spatially blind approaches perform segmentation in certain attribute/feature spaces. popular segmentation techniques that fall within the notion of being spatially blind involve clustering and histogram thresholding. spatially approaches are guided by spatial relationships of pixels for segmentation. their primary objective is to form pixel groupings that are compact or homogeneous from a spatial standpoint, irrespective of their relationships in specific feature spaces. the use of region and edge information explicitly or in an integrated framework are the widely-accepted main solutions. between spatially blind approaches we focused on clustering based segmentation approach, appearing more suitable with our goal to automatically select and segment the highlighted areas. in its simplest form, clustering is a spatially blind technique wherein the image data is viewed as a point cloud on a one-dimensional (1-d) gray scale axis or in a 3-d color space depending on the image type. the essence of a typical clustering protocol is to analyze this gray/color intensity point cloud and to partition it, using predefined metrics/objective functions to identify meaningful pixel groupings also known as classes or clusters. furthermore, the clustering process is done such that, when complete, the pixel data within a specific class possess, in general, a high degree of similarity while the data between classes has low affinity. in detail, we experimented the k-means clustering, an algorithm aiming to optimize the partitioning decisions based on a user-defined initial set of clusters that is updat-ed after each iteration. the k-means algorithm, in particular, partitions a set of n-pixels into k clusters by minimizing an objective function. main limitations concern selecting/initialization of number of clusters and the fact that during the space partitioning process the algorithm does not take into consideration the local connections between the data points (color components of each pixel) and its neighbors. this fact will restrict the application of clustering algorithms to complex color-textured images since the segmented output will be over-segmented. we implemented the version of the algorithm called the ‘filtering algorithm’ [42], that use a k-dimensional (kd) tree representation of the image data. the biggest advantage of this approach was that, since the kd-tree representation was formed from the original data rather than from the computed centers, it did not mandate an update in its structure for all iterations, in contrast to the conventional k-means architecture. spatially guided segmentation techniques figure 6 results of technique based on layer decomposition using a single image introduced in [31]. 46 cultura e scienza del colore color culture and science | 07 | 2017 | 39 57 apollonio f. i., ballabeni a., gaiani m. issn 2384-9568 doi: 10.23738/ccsj.i72017.04 typically employ protocols involving growing, splitting, and merging individually or in suitable combinations. we focused on watershed transformation that can be classified as a region-based segmentation approach. the main concept of this algorithm is derived from geography. the watershed lines determine boundaries which separate image regions. the watershed transforms computes catchment basins and ridgelines (also known as watershed lines), where catchment basins corresponding to image regions and ridgelines relating to region boundaries. we experimented the meyer’s watershed algorithm [43] consisting of the following basic steps: 1. add neighbors to priority queue, sorted by value 2. choose local minima as region seeds 3. take top priority pixel from queue a. if all labeled neighbors have same label, assign to pixel b. add all non-marked neighbors 4. repeat step 3 until finished. watershed segmentation possesses several advantages such as ability to provide close contours even in low contrast regions with weak boundaries, and means to serve as a stable initialization for more sophisticated segmentation mechanisms. on the cons, the output achieved by a watershed transform is often oversegmented and requires postprocessing schemes involving region merging and markers (connected components branding flat regions or objects in images) to yield a more suitable out-come. a major portion of segmentation practices can be viewed as being either spatially blind or spatially guided. however, there are several techniques that may not distinctly fall in any of these two categories but provide good results. between these techniques we focused on methods using specialized image features as histogram of oriented gradients (hog), local binary patterns (lbp), maximally stable extremal region (mser). we experimented mser a technique proposed by [44] to find correspondences between image elements from two images with different viewpoints. mser technique produces blobs, i.e. highly featured regions in the sense that they are stable and salient, and have multiscale structure. mser regions are connected areas characterized by almost uniform intensity, surrounded by contrasting background. they are constructed through a process of trying multiple thresholds. when compared to the algorithms which rely on intensity extrema, mser is more stable because it stems from stability extrema [45]. we referred to [46] which propose a new multi-scale image segmentation approach based on mser. the approach can segment natural images without any user intervention. it accomplishes the segmentation by collecting msers and then rearranging them onto the image plane in an appropriate order that would generate desired segmentation of whole image. to denoise and smooth the region boundaries, hierarchical morphological operations and an optimal sequence of them are developed. at the end, we processed segmented images with algorithms for single image specular removal that in the original formulation not present this extra-step and tested using the whole image. results adding image segmentation are in figure 7. although some improvements have been observed, however, the road ahead remains long and hard. after these fails, we tried another strategy: the use of techniques employing multiple images. multi-image systems exploit information contained in an image sequence of the same scene taken either from different points of view or with different light information. such sequence contains much more information on specularity than a single image since the specular reflection varies through the images. in the case of a sequence of images taken from different points of view, scene points showing specular reflection in a view can exhibit purely figure 7 color based segmentation results on our reference image: (a) k-means clustering technique; (b) region-based segmentation approach based on watershed transformation; (c) mser based segmentation. 47 cultura e scienza del colore color culture and science | 07 | 2017 | 39 57 highlight and specular reflection removal in photogrammetric techniques applied to architectural heritage 3d modeling issn 2384-9568 diffuse reflection in other views. by matching specular pixels to their corresponding diffuse points in other views, it is possible to determine the diffuse components of the specularities. some methods assume a fixed camera that is able to capture a set of images with different mixing of the layers through various means, e.g. rotating a polarized lens, changing focus, applying a flash, or using hdr techniques. all these methods present many drawbacks in our context. the first three approach-es demonstrate good results, but the ability of controlling focal change, polarization, and flash is rarely possible. the third technique (hdr) appear more reliable to our field, not requiring specific equipment. some studies of last years show accurate color-calibrated tone mapped hdr images [47,48], but the algorithms in the literature were not directly usable, and their limits are still uncertain. in particular, we discarded the most recent pipeline purposed in [49] to avoid an unclear all-in-one processing. we developed a new hdr-based processing similar to that in [50]. our goal is not only composing a single hdr from multiple color images with different exposure levels [51], but also reducing the color distortion during the tone mapping process. we capture hdr images of the scene in raw file format, minimum camera image processing in the captured images, with and without inside a x-rite classic colorchecker. the color checker is photographed under the same conditions and with the same exposure bracket as the hero shot. the calibration is performed using this single hdr image containing the x-rite ccc, using reference values in the ciexyz space [52]. we generated the hdr image using the reconstruction technique proposed from [53] following the study of the performance bounds of [54]. we tonemapped the scene image with specular reflections, trying to minimize these effects and we applied the same setting to tonemap the image with the target, using the technique proposed in [55]. finally, we applied the same processing of color calibration applied to the other ldr images. as you can see in figure 5, final results are not very accurate and obtained pictures are impossible to merge with the whole pipeline, where ldr images have been used. having an hdr checker shot may not always return accurate or desirable results since the tone mapping software can sometimes create colorcasts. hdr tone mapping operators often exaggerate color-casts in a scene, and include some version of local adaptation, so the color checker is really just a starting point. to measure the error of the color corrected hdr image of colorchecker, we calculate the average color difference de between the colorcorrected hdr image and the checker reference data (figure 5). a different approach to reflections separation consists in the exploitation of motion between multiple images [56, 57]. by analyzing the movie sequence, diffuse and specular components can be recovered. these approaches produce good results, but the constraint on scene geometry and assumed motion of the camera limit the type of scenes that can be processed. a second problem of these techniques is the indefinite number of images to be employed to figure 8 on the left color calibrated ldr image, on the right color calibrated hdr image. in the middle: color difference deab; top color calibrated ldr image, below color calibrated hdr image. 48 cultura e scienza del colore color culture and science | 07 | 2017 | 39 57 apollonio f. i., ballabeni a., gaiani m. issn 2384-9568 doi: 10.23738/ccsj.i72017.04 the purpose. the number of images to be used depends on working conditions, such as the distribution of ambient lighting sources and the viewing direction of the camera. furthermore, multiple images increase both the processing time and storage. in order to reduce the number of images to be used, stereo images [58] and flash/no-flash image pairs [59, 60] have shown to provide enough information for solving the dichromatic reflection problem. lin et al. [61] present a method based on color analysis and multi-baseline stereo that makes use of sequence of images to achieve the separation of specular reflection. nevertheless, extra devices and equipment were incorporated. this makes very hard the practical applications of these techniques to the urban context. a second problem in the multi-image area concerns image alignment. the use of local invariant features [2] is a powerful solution because these features are robust to typical appearance variations (illumination, blur, compression), and a wide range of 3d transformations. initial feature matching is often followed by geometric filtering steps, which yield very reliable matches of 3d rigid scenes [62]. these operations are nothing more than the first part of our photogrammetric workflow, in this way appears easy to embed the specular removal process in the whole pipeline. along this line [63, 64] proposed an image processing pipeline based on the use of local invariant features for building an image of a painting from a set of photographs taken with a hand-held camera in a non-controlled environment where highlights may appear. the steps of the pipeline are the following: (a) sift, (b) ransac, (c) segmentation of bursts, (d) subpixel resampling, (e) blur weighting, (f) weighted average fusion, (g) asift, (h) distortion correction by polynomial approximation and subpixel resampling, (i) histogram specification, (j) vector median of gradients, and (k) poisson fusion. to apply this workflow in our field the main drawback concerns the original assumption of like-planar surfaces and a non-simple pre-processing image alignment that limits the benefits to color fidelity without improving the results of photogrammetric pipeline. same problem appears with [65], where is illustrated a robust technique for layer separation from multiple images which exploits the correlation of the transmitted layer across multiple images, and the sparsity and independence of the gradient fields of the two layers. this solution need a pre-processing technique similar to [64] to accurately align images, and manual interaction to initialize the process. multi-image techniques and alignment using local and global features were also the last frontier of layer separation techniques, which could be viewed as a superset of dichromatic approach. above all these attempts to solve major lacks of the single image method [66]: the user involvement and the limited number of cases where it’s possible to obtain great quality of results. the basic assumption of these algorithms is that interference decomposition should result in component images having fewer edges and corners than the original image. in [67], levin and weiss considered a simpler problem, in which the user provides labels of component images for a number of critical gradients in the interference image. however, the problem is still ill-conditioned. a sparsity prior was introduced, which states that the output of any derivative filter tends to be sparse. more explicitly, the histogram of the output of a derivative filter is peaked at zero and fall off rapidly out to the two extreme ends of the histogram. a probability function characterized by the sparsity prior was constructed, which served as the criterion of interference decomposition. features of multi-image specular removal techniques depicted their use as the most appropriate starting point for our use case. 3. specular reflection removal method separating reflections from a single image is an ill-posed problem, as it requires extracting two layers from one image: in absence of additional knowledge about the scene being viewed there are an infinite number of valid decompositions. to make the problem tractable additional information, either supplied from the user or from multiple images, is required. our approach is an improved and calibrated version of the pipeline set by [16] and [66, 67]. moreover [66, 67] offer a solution to layer separation problem using a single image that needs to be manually labeled and where different labels represent background or reflection parts of the image itself. following results on the statistics of natural images, these authors used a sparsity prior over derivative filters. they first approximate this sparse prior with a laplacian prior obtaining a simple, convex optimization problem. then they use the solution with the laplacian prior as an initialization for a simple, iterative optimization for the sparsity prior that efficiently find the most probable decompositions using linear programming. the results show a clear advantage in a technique that is based on natural scene statistics rather than one that assume a gaussian distribution. beside effective results, the developed technique has a very strong constraint: it requires user intervention to label the image manually. to remove the 49 cultura e scienza del colore color culture and science | 07 | 2017 | 39 57 highlight and specular reflection removal in photogrammetric techniques applied to architectural heritage 3d modeling issn 2384-9568 figure 9 layer separation pipeline. need for user markup, [16] suggest examining the relative motion in a small set (e.g. 3-5) of images to label gradients as either reflection or background gradients in an automatic way. first, the images are aligned using sift flow [15]. gradient variations are examined among the image set. gradients with more variation are assumed to belong to the reflection component while constant gradients are assumed to belong to the background component. the input of [16] approach is a small set of k images of the same subject taken from slightly varying viewpoints. authors assume that the background dominates in the mixture image and the images are related by a warping, such that the background is registered and the reflection layer is changing. this relationship can be expressed as: where is the -th mixture image, are warping functions caused by the camera viewpoint change with respect to a reference image. pipeline steps are then, as in figure 6: a. for each image: • warping functions estimation. it is accomplished by distorting the input image to the reference image using sift flow algorithm an extension of the original sift lowe technique [2] allows extracting keypoints from an image and assigning robust descriptors to them for every image pixel. these descriptors are matched to those of another image in order to produce a list of pairs of points. this list of matching points is used to estimate the parameters of the transformation-warping vector between the two images. a robust estimation method ransac is used to automatically reject wrong matches before computing the (2) transformation. • edge separation: the presence of a static ib in the image set allows the identification of gradient edges of the background layer ib and edges of the changing reflection layers iri . more specifically, edges in ib are assumed to appear every time in the image set while the edges in the reflection layer iri are assumed to vary across the set. this means edges can be identified evaluating the frequency of a gradient appearing at a particular pixel across the aligned input images. • layer reconstruction: after labeling edges as background or reflection, the two layers are reconstructed using an optimization technique that imposes a sparsity prior on the separated layers as described by [66, 67]. b. single images results combination. as in the original paper, we assume that the minimum value across all recovered background layers may be a proper approximation of the true background. as such, the last step is to take the minimum of the pixel value of all reconstructed background images as the final recovered background, as follows: we iterate the original pipeline [16] for each initial image, as all the images were containing useful information for 3d reconstruction and all of them needed to be processed in our photogrammetric general pipeline. our photo datasets were mainly containing pictures of porticos. this issue increases the complexity of the problem, since this kind of photos is characterized by very high contrasts, backlight, overexposed areas and underexposed (3) 50 cultura e scienza del colore color culture and science | 07 | 2017 | 39 57 apollonio f. i., ballabeni a., gaiani m. issn 2384-9568 doi: 10.23738/ccsj.i72017.04 ones (see figure 3). this problem has been address working on the separation thresholds with which gradients are identified as belonging to the background or the reflection layers. 4. discussion and results in figures 10, 11, 12 are the results of the use of our method to the different case of shop window and polished floor. from the point of view of the use inside the whole photogrammetric pipeline, the use of reconstructed layer separated images, leads to a strong improvement if compared to the use of original highlighted images, and we consider the study as final. results in figures 13, 14 and table 1, where are reported typical parameters addressing quality in photogrammetric processes demonstrate our affirmation. moreover, even if results reconstructed images apparently show many approximations and artifacts, images are evidently good enough to be processed through the whole pipeline as the software, assigning color per vertex, tends to discard the re-maining highlighted surfaces. effectively, if we analyze separately the layer separation results we can see that we just begin a long road. the key problem is in the warping step, with the estimation of the warping functions, , to register the input to the reference image. for our purposes, we use a combination of sift flow and ransac to register a pair of images by a homography. this solution computes descriptors densely (i.e. figure 10 example of separation of background ib and reflection ir layers separation results: shop windows. 51 cultura e scienza del colore color culture and science | 07 | 2017 | 39 57 highlight and specular reflection removal in photogrammetric techniques applied to architectural heritage 3d modeling issn 2384-9568 for every pixel), instead of sparsely, to have an improved registration. however, the planarity constraint often leads to reconstruct image regions slightly misaligned, especially when the scene presents elements on different planes, that is very often our case. traditional dense correspondence method like optical flow, that are based on image intensity, even with our assumption that the background should be more prominent than the reflection layer, gave poor performance due to the reflection interference. however, images with very strong reflectance can produce poor alignment as sift flow may attempt to align to the foreground, which is changing. this will cause problems in the subsequent layer separation. while these failures can often be handled by cropping the image or simple user input, it is a notable issue. a second issue concern large displacement between images, moreover usual in our case as our sequence of images are from a photo camera and from well-spaced viewpoints. optical flow techniques are closely related to motion estimation and motion compensation from sequence of frames and were developed for video se-quences where displacements between frames are usually limited. a basic assumption is then the local smoothness assumption. it is usually incorporated into a joint energy based regularization that rates data consistency together with the smoothness in a variational setting of the flow. one major drawback of this setting is that fast minimization techniques usually rely on local linearization of figure 11 example of separation of background ib and reflection ir layers separation results: shop windows & porticoes. 52 cultura e scienza del colore color culture and science | 07 | 2017 | 39 57 apollonio f. i., ballabeni a., gaiani m. issn 2384-9568 doi: 10.23738/ccsj.i72017.04 the data term and thus can adapt the motion field only very locally. hence, these methods have to use image pyramids to deal with large displacements [68]. in practice, this fails in cases where the determined motion on a lower scale is not very close to the correct motion of a higher scale. also, the use of purely data based techniques like approximate nearest neighbor fields [69] (annf) and sparse descriptor matches [70] allow an efficient global search for the best match on the full image resolution. however, sparsity causes local gaps in the motion field that must be filled. another challenging issue is when the background scene has large homogeneous figure 12 example of separation of background ib and reflection ir layers separation results: marble pavements. figure 13 final 3d model of our automatic photogrammetric pipeline. above: using the highlighted images; below: using the layer separated images. regions. in such cases there are no edges to be labeled as background. this makes subsequent separation challenging, especially when the reflection interference is weak but still visually noticeable. finally, a problem that emerges when applying dense descriptors is invariance [67]; unlike interest points, which allow for some estimation of local scale and orienta-tion, on arbitrary image locations scale estimation is not obvious. this is a significant issue in our context, because generally images have not a clear foreground and background, and building edges sometime are oblique in respect to the picture plane. for this reason, in the future we will investigate 53 cultura e scienza del colore color culture and science | 07 | 2017 | 39 57 highlight and specular reflection removal in photogrammetric techniques applied to architectural heritage 3d modeling issn 2384-9568 figure 14 final 3d model of our automatic photogrammetric pipeline. above: using the highlighted images; below: using the layer separated images. without specular removal with specular removal oriented images 63/67 64/67 pba quality 0.130 0.087 points from more than 3 cameras 101751 114618 dense point cloud 12112000 14107000 point on image _dsc3201 14888 2202 inlier matches 01_02 7227 7435 time matching (sec) 62 1 further scale problem. to address these problems, we experimented some recent techniques appearing the most reliable between the many solutions developed in the last years. to face typical invariance and background/ foreground problems, we implemented a generalized image matching algorithm called daisy filter flow (dff) [71]. fol-lowing the same spirit of the sift flow authors developed an algorithm achieving much more robust performance in efficiently matching images of challenging non-rigid photometric and geometric variations, or across different scenes than the ex-isting techniques. our approach is built upon a few established techniques but also extends them, which are 1) daisy descriptors [72], 2) filter-based efficient flow field inference, and 3) the patchmatch fast search [73]. inspired by the patchmatch filter (pmf) work [73], it generalizes the pmf method in two important ways: daisy descriptors are employed and extended for general image matching; to search across scales and rotations beyond just translations. as a result, dff algorithm allows performing spatially regularized, dense descriptor-based correspondence field estimation efficiently in a high-dimensional space. being able to do so explains the key advantages of the dff method in both matching robustness and computational efficiency. results are in figure 15. a second attempt was made addressing the treatment of scale-invariance. we imple-mented scalemap [74], a very recent algorithm aiming figure 15 separation of background ib and reflection ir layers separation results using [72] instead of sift flow in our solution: shop window of figure 10. table 1 photogrammetric results for the porticoes dataset 54 cultura e scienza del colore color culture and science | 07 | 2017 | 39 57 apollonio f. i., ballabeni a., gaiani m. issn 2384-9568 doi: 10.23738/ccsj.i72017.04 to deal with the large-scale differences in different image locations. authors demonstrated that scales estimated in sparse interest points may be propagated to neighboring pixels where this information cannot be reliably determined. in detail, they presented and implemented three different means for propagating this information: using only the scales at detected interest points (geometric propagation), using the underlying image infor-mation to guide the propagation of this information across each image, separately (image-aware propagation); and using both images simultaneously (match-aware propagation). each of these methods considers progressively more information in order to more reliably propagate scales. we tested this approach and results are in figure 16. finally, we tested edge-preserving interpolation of correspondences (epicflow), a novel stateof-the-art optical flow estimation method particularly suitable to approach large displacement of objects in subsequent images [75]. epicflow computes a dense correspondence field by performing a sparse-to-dense interpolation from an initial sparse set of matches, leveraging contour cues using an edge-aware geodesic distance. the approach builds upon the assumption that contours often coincide with motion discontinuities and then it is easy to handle occlusions and motion boundaries. the resulting dense correspondence field is fed as an initial optical flow estimate to a one-level variational energy minimization initialized with the dense matches. results are in figure 17. comparing figures 10, 15, 16, 17 we could summarize that tested approach achieves similar performance as the sift flow method in our case with slight improvements relative to the specific issue addressed. these results show that substantial improvements are possible in the future essentially trying to combine the individual effects in a global solution. a last remark is related to the computational complexity of the method. currently, the main problem concerns image warping that is a very expensive process, both time and memory consuming, often needing half hour and more than 128 gb of ram to compute our 14 mpx images. we estimated that increasing parallelization should heavily affect time and computational resources yet maintaining consistency with the whole photogrammetric pipeline. figure 16 separation of background ib and reflection ir layers separation results using [75] instead of sift flow in our solution: shop window of figure 10. figure 17 separation of background ib and reflection ir layers separation results using [75] instead of sift flow in our solution: shop window of figure 10. 55 cultura e scienza del colore color culture and science | 07 | 2017 | 39 57 highlight and specular reflection removal in photogrammetric techniques applied to architectural heritage 3d modeling issn 2384-9568 5. conclusions in this paper, we faced the problem of specular reflections, an inevitable effect in ah urban environment, in the context of automatic photogrammetry of ah 3d reconstruction and architectural modeling. after careful evaluation of existing solutions and their applicability to our case study, we modeled the problem as layers separation problem, developing a solution completely integrated in the automatic photogrammetric pipeline. we reuse existing data to arrange new results using a multi-image technique, obtained improving and calibrating the pipeline set by [16] and [66, 67]. we iterate the original pipeline [16] for each initial image, as all the images were containing useful information for 3d reconstruction and all of them needed to be processed in our photogrammetric general pipeline. the process of acquisition of the images to get the finished 3d model is therefore unique and the process for acquiring and visualizing the correct perceived color is fully integrated with the process of shape reconstruction. from the point of view of the use inside the whole photogrammetric pipeline, the use of reconstructed layer separated images, leads to a strong improvement in shape reconstruction if compared to the use of original highlighted images, because unwanted effects as those in figure 1 completely disappears. conversely results concerning diffuse color reconstruction are quite limited due to imprecision of the techniques existing to estimate of the warping function. at time the best solution possible in our case to model diffuse color is to select an image where specular effect not appears or are limited and map the color directly from it. future works will be done in this area finding warping function more accurate. acknowledgments a special thanks to li yu, for is valuable help and for distributing the code used. funding this research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. conflict of interest the authors declare no conflict of 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[75] j. revaud, et al., “epicflow: edge-preserving interpolation of correspondences for optical flow”, cvpr proceedings, 2015, pp.1164-1172. cultura e scienza del colore color culture and science 59 cultura e scienza del colore color culture and science | 08 | 2017 issn 2384-9568 agata kwiatkowskalubanska akwiatkowska@asp.krakow.pl faculty of industrial design, academy of fine arts in krakow, colour as a mass product. designing of the collection of interior paint colours for the polish market abstract the paper concerns the issue of using colour in contemporary polish residential interiors based on the example of design and sales of paint collections by selected polish manufacturers. the collections of colours, which usually contain between 40 and 60 shades, constitute a popular offer for the customers who do not employ interior designers and feel no need for more advanced colour selection from mixers. a collection of colours with a rather small number of shades makes it easier for the customers to choose the colour and is an economically beneficial alternative to mixing colours based on the currently used colour systems. designing colour collections for two large polish companies over several years has allowed me to make certain interesting observations concerning the specific colour preferences of the polish customer, based on both sales results and the colour trends established by the polish market, which are often different from the trends of western europe. the presentation will recognise the changes made to the collections in the years 2011, 2012, and 2013 – which will reflect both the changing colour trends and the local colour traditions or inclinations resulting from climatic, historical, and economic conditions. keywords colour design, colour in architecture, colour in interiors citation: kwiatkowska-lubanska a., (2017) ‘colour as a mass product. designing of the collection of interior paint colours for the polish market’, cultura e scienza del colore color culture and science journal, 08, pp. 59-63, doi: 10.23738/ccsj.i82017.06 received 13 january 2016; revised 28 july 2017; accepted 31 august 2017 agata kwiatkowska-lubanska is an expert in the field of colour design and the founder of the polish colour association. she is currently a professor at the faculty of industrial design of the academy of fine arts in krakow. her main research interests include colour environmental design, colour trends forecasting and colour communication. as a colour consultant she has collaborated with a range of industry partners in poland. 60 cultura e scienza del colore color culture and science | 08 | 2017 | 59 63 kwiatkowska-lubanska a. issn 2384-9568 doi: 10.23738/ccsj.i82017.06 1. historical background colours used in interiors, in a particular country, are connected with such factors as local tradition, materials and dyes, as well as colour preferences of its residents which reflect the surrounding flora, climate and landscape, as well as colour symbolism, and various aspects of material culture. in poland, during the period of the communist regime, economic problems caused that the opportunities of buying elements of interior design were very limited. paints produced by the state companies available on the market were also of a very narrow range of colours. more demanding consumers who wanted to stand out against all-pervasive mediocrity were forced to turn to house painters who helped them achieve exceptional colours depending on their individual needs by mixing pigments. on the other hand, in public buildings and facilities, a typical combination of colours was used, which caused that staircases in residential buildings, as well as school interiors, public administration buildings and health service facilities looked almost identical. at the same time, the economic and political crisis of the 1980s leading to the political transformation in 1989 caused that most buildings were left non-renovated, and it brought about general dullness of surroundings. 2. colour standards in poland thus, craving for colour was one of the effects that a capitalist system brought in towns. state companies like zjednoczenie przemysłu farb i lakierów polifarb were divided and taken over, in part, by foreign companies; what was left originated polish local brands. in the 1990s, the natural colour system was introduced in poland due to the efforts of janusz konaszewski and ryszard bojar, and it became the most popular standard of colour notation. then, there were initiated works concerning the creation of the first polish pallet of colours. the color koncept studio of ryszard bojar prepared a set of interior and elevation colours inspired by the colours of the polish landscape. for a year, a team consisting of ryszard bojar, violetta damięcka, krystyna arska, agnieszka putowska, sylwia dobrowolska examined selected regions of poland in a manner inspired by geography of colour by philippe lenclos (lenclos, lenclos 2008) and it resulted in a selection of several dozen of colours grouped in four categories: yellow (g90y-y50r), red (y60r-r10b), blue (r20b-b10g), green (b50g-g80y) and off-white (c=00, c=02)[2]. 3. colour identity the search for the colour identity of the polish territory was also based on references to folklore tradition that had generated a number of original patterns in many regions. in her doctoral dissertation titled colours in rural architectural and landscape complexes, with special emphasis put on the southern poland area, (tarajko, 2005) justyna tarajko points out a range of hues and colour sets used in rural houses of the krakow and sandomierz areas, as well as of the podhale and the powiśle regions. the analysis includes dyes and sets of colours, as well as regular ornaments used both inside and outside buildings. the application of dyes produced from local clay and lime, along with natural colours of wood, created a pallet of colours well harmonized with the surrounding flora and natural scenery. however, when traditional wooden architecture was replaced with a chaotic pseudo-modern one, particularly in places where there were no area development plans, it brought about visual chaos, especially in terms of colours. 4 colour outside on the other hand, natural colours of brick and stone, as well as colour sets resulting from the combination of those materials, have been largely predominant in urban architecture, particularly in the area of southern poland. jurassic limestone has been a building material particularly popular in małopolska, and it was obtained in the form of limestone bricks used for secular and sacred buildings from the middle ages, through the gothic, renaissance, and baroque era, nearly to modern times (rajchel, 2004). the combination of dark red bricks and warm white lime is a characteristic element of the architecture of the krakow area landscape. limestone has also been used in the form of cobblestones, frequently combined with a porphyry material. the precincts of the st. mary’s basilica in krakow are a perfect example of this usage. light yellow dolomite has also been a popular material which greyed under the influence of atmospheric factors. a lot of architectural elements, both inside and outside, have been made with yellow and grey subcarpathia sandstone, sometimes with a reddish hue. there could also be found dark brown or rust-coloured sandstone, depending on the location of the deposit where it was extracted. at present, in spite of the fact that natural stone is not so popular in architecture anymore, it should be noticed that warm colours of yellowish, reddish and beige hues are still preferred both for interior and external designs, as it has been shown, among others, in research conducted at the academy of fine arts in 61 cultura e scienza del colore color culture and science | 08 | 2017 | 59 63 colour as a mass product. designing of the collection of interior paint colours for the polish market issn 2384-9568 krakow (zeszyty naukowe katedry przestrzeni i barwy, 2010). 5. colours for interior decoration a necessity of choosing colours for interior decor causes a lot of problems for people who are not professionals in the field of design and architecture. therefore, the experience of polish companies shows that extensive colour charts derived from a standard colour notation system (ncs, munsell, acc) are solutions rather for designers and architects than for an average consumer. that is why, in the early 1990s, collections of ready-made colours appeared in the offer of many companies. in many cases, a proposed set of colours was created without designer’s participation, being a result of experience of a sale department, and it included pastel colours (without addition of black). of a distinct chromatic hue which looked good in small colour samples yellow, green and orange. these were the colours which were supposed to help people overcome the dullness of concrete buildings typical of the architecture of the communist period having such bad connotations. the global best selling colours (the global best selling colours, 2008) research which was carried out by the akzo nobel decorative paints company in 2008 proved that, in comparison to the residents of western european countries, the poles show a much stronger tendency to use pure colours, warm in particular, but they reject achromatic and cold colours. moreover, the analysis carried out for marketing purposes by fabryka farb i lakierów śnieżka showed that, in 2010, the best selling colours for interiors were warm hues of beige, yellow, and orange: 1 – desert flower (ncs 1510 – y40r), 2 – sunshine (ncs 1040 y10r), 3 – scorching savannah (ncs 0515 y40r), 4 – hot summer (0550 y30r). 6. colour names names constitute an important element of a set of ready-made colours; names should be associated with common experience of colours and usually connected with observations of nature, changing seasons or semi-precious stones. names given to particular colours stimulate imagination and, at the same time, facilitate remembering paint hues. here are some examples of names of the collections available on the market: colours of nature (ffil śnieżka), colours of the elements (bolix), seasons (nobiles), garden of colours (jedynka), magic of refined colours (ffil śnieżka), decoral – fashion (decoral), colours of the world (dulux). an analysis of different names of colours included in these collections makes one aware that there are no names of colours in the polish language connected with architecture or local pigments. at the same time, the real hues corresponding to names like bunch of roses, spring leaf, mountain crocus, field of sunflowers or juicy apricot are a lot more vivid than the colours of paints bearing those names. this confirms that an average consumer has a taste for pure and bright colours which are not always suitable for interior usage. the conducted study also shows that descriptive names have a clear advantage over the numeric notations resulting from the adopted system. 7. colour trends collections of ready-made colours are annually updated so that companies could have a chance to announce current colour trends for a given year. however, in this case, the scope of changes is very limited due to the fact that consumers are accustomed to particular colours, and due to their reluctance to be driven by trends while changing interior designs. as it has been shown by the research carried out by the institute of industrial design in warsaw in 2011, the basic reasons for choosing interior colours are as follows: individual colour preferences of consumers (48%), price (18%), colours of other furnishings (15%), family and friends’ advice (8%), designs derived from the interior and architectural magazines (5%), sale special offers (4%), others (2%). therefore, in spite of the fact that some companies announce colour trends each year, in fact, they are mostly based on the same shades, juxtaposed in different combinations, alternatively supplemented with a few season hues. having participated many times in groups setting trends in ready-made colours for various polish brands, i must state that these trends are mainly of marketing character and are based on the experience of large european concerns. new colours are introduced in a very limited range so as to preserve the basic character of the collection and reduce the risk factor to the maximum. new colour trends are often intended for colours produced in mixers, but not for those sold as ready-made ones. it is the effect of the situation where the consumers interested in new trends are those who can afford to buy more expensive brands and seek advice from an interior designer. 8. designing of colour collections in poland in 2011, i started cooperation with the śnieżka company a producer of interior paints available on the polish market and in other countries of eastern europe. as their consultant, i was 62 cultura e scienza del colore color culture and science | 08 | 2017 | 59 63 kwiatkowska-lubanska a. issn 2384-9568 doi: 10.23738/ccsj.i82017.06 responsible for redesigning the colours of nature collection, and i participated in the creation of the satin brand newly introduced onto the market. the company offers products in the medium price segment, and those products constitute a representative reflection of an average polish consumer’s preferences. colours of nature is a collection existing on the market since 2004, and in the beginning it consisted of 40 colours; in the successive stages, it was extended to 53 colours in 2014. at first, it was divided into five hues: yellow, orange, red, green and blue (combined with purple), and it only included colours having the dominant content of white (ncs s0505 – 0540), derived from a limited number of colour triangles. in 2007, it turned out that the collection clearly lacked warm neutral colours: off-white, beige and brown. the range of colours was extended and arranged in the following groups: neutral, yellow, red and orange, green, as well as blue and purple. the brand offered only one hue of warm grey. in 2011, because of the increasing popularity of cool and neutral colours, i suggested that a separate line of colours should be added to the collection. however, when research was conducted, it turned out that this type of changes would not be accepted by consumers. in subsequent years, three cool greys appeared gradually on the market, but their sale is mainly connected with consumers coming from big cities. moreover, four colours of the blue and purple group were phased out. in 2012, the greinplast company from rzeszów requested my help in the creation of a new brand of ready-made colours of paints for residential interiors. the company, which addresses its products to architects and construction companies, previously used a wide range of ncs colours, mixed according to the consumers’ needs. however, at the request of individual consumers, a decision was made to extend the offer by about 40 ready-made paints. the subject of the project was both designing a series of colours, their names, and suggested combinations, as well as preparing sample applications of the colours in residential interiors on the basis of photos coming from a bank of photographs. the greinplast company sells its products in southern poland; therefore, colour preferences of residents of that region were of special importance when choosing the colours. a set of different kinds of construction and finishing materials, as well as paints traditionally used in the architecture of the region, became the base for the choice of colours for the collection. the following materials were chosen (among others): jurassic limestone, subcarpathia sandstone, alabaster, marble from the świętokrzyskie region, and porphyry from the region of krzeszowice, as well as ceramic brick, and concrete. colours were analysed on the basis of ncs, and it led to the creation of a set of about 120 colour samples. the final collection, introduced onto the market in the autumn of 2013, consists of 40 colours divided into five hue lines. because of the fact that the collection is mainly addressed to a group of architecture and construction professionals, the company decided to introduce sixteen neutral colours: eight warm and eight cool hues. the proposed names are directly related to the architectural materials and pigments. a summary of sales results planned for the autumn 2014 will enable the company to verify the colours of the collections. 9. conclusions a study of the polish market carried out through a period of the previous four years allows us to draw conclusions concerning both consumer preferences in connection with the range of colours used in interiors, as well as directions of changes to which those preferences succumb. colour notation based on ncs allows one to determine the scope of the changeability of colour features like whiteness, blackness and chromaticity. the offer available on the paint and coating market, which is becoming better and better, causes that consumers are more aware and demanding, and in the future it may lead to more common usage of a wider pallet of colours (of the ncs for instance) obtained in paint mixers, and thus, to the improvement of the appearance of private flats or public buildings and facilities.. funding this research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. conflict of interest the author declares no conflict of interest including financial, personal or other relationship with other people and organizations within three years of beginning the submitted work that could inappropriately influence, or be perceived to influence, this work. bibliography bojar r. (2013) ‘colour day 2013’ proceedings, academy of fine arts, krakow lenclos j-ph., lenclos d. (2008) ‘colors of the world. geography of color’, norton & company, london rajchel j. (2004) ‘kamienny kraków’ uczelniane wydawnictwo naukowo-dydaktyczne agh, krakow. 63 cultura e scienza del colore color culture and science | 08 | 2017 | 59 63 colour as a mass product. designing of the collection of interior paint colours for the polish market issn 2384-9568 tarajko j. (2005) ‘kolor w wiejskich zespołach architektoniczno-krajobrazowych ze szczególnym uwzględnieniem polski południowej’, phd thesis, politechnika krakowska, krakow the global best selling colours 2008, www.akzonobel.com zeszyty naukowe katedry przestrzeni i barwy, akademia sztuk pieknych im. jana matejki, kraków 2010 cultura e scienza del colore color culture and science 71 cultura e scienza del colore color culture and science | 06 | 2016 issn 2384-9568 1tiziana cavaleri tiziana.cavaleri@ centrorestaurovenaria.it 2isabelle clonier i.clonier@critt-horticole.com 1,3paola croveri paola.croveri@unito.it 1annamaria giovagnoli annamaria.giovagnoli@gmail. com 1anna piccirillo anna.piccirillo@ centrorestaurovenaria.it 1centro conservazione e restauro “la venaria reale”, italy 2arrdhor critt horticole, france 3 chemistry department, university of turin, italy colorimetric and spectrophotometric analyses for an ecoinnovative application of natural dyeing in textile conservation abstract an eco-innovative application of natural dyes and nontoxic mordants was recently experimented at centro conservazione e restauro “la venaria reale” (ccr, italy) in the conservation of some historical tapestries, in collaboration with coulers de plantes (cdp, france). until now, textile conservation makes use of synthetic pre-metallized dyes that contain heavy metals such as chrome and cobalt: the synthetic dyes allow to obtain different hues and saturation levels of the textile fibres simply varying ratio and concentration of three primary dye. this project aimed at finding ecofriendly materials for substituting the synthetic ones. all dyes and mordants used in this application were produced by cdp inside the innocolors project, carried out by ccr and arrdhor critt horticole. a palette of textile fibres was made with 7 natural dyes and 4 nontoxic mordants with more than 300 different recipes. spectrophotometric and colorimetric analyses were used to evaluate and compare the natural palette with the synthetic one. as expected, the colours of the synthetic palette show to vary linearly changing the ratios of the three pre-metallized dyes, whereas, in the natural palette, each ingredient plays an important, not predictable rule on the final colour. the analyses so carried out allowed to better understand in particular the influence of mordant on the final colour of the textile fibres. the study allowed to modulate the recipes in order to obtain precise colours. the samples’ lightfastness was monitored and studied. at the end, some lacunae on historical tapestries were integrated in this innovative way. keywords natural dyes, nontoxic mordants, eco-innovative dyeing, textile conservation, historical tapestry, fiber optics reflectance spectroscopy (fors), colorimetry citation: cavaleri t., clonier i., croveri p., giovagnoli a., piccirillo a. (2016) ‘colorimetric and spectrophotometric analyses for an ecoinnovative application of natural dyeing in restoration’, cultura e scienza del colore color culture and science journal, 06, pp. 71-79, doi: 10.23738/ ccsj.i62016.07 received 20 january 2016; revised 27 september 2016; accepted 30 september 2016 tiziana cavaleri graduates in science and technology applied to cultural heritage at the department of chemistry, university of turin (italy). she works at ccr as conservation scientist since 2009. her research focuses on noninvasive analytical methods such as hyperspectral imaging and uv-vis-nir reflectance spectroscopy, colorimetry and colour appearance, remote sensing, rgb rendering and lighting science. isabelle clonier has a phd in phytochemistry at the national school of chemistry in toulouse (france). since 2001 she’s textile engineer at arrdhor-critt horticole: her research in the field of natural dyes focuses on sourcing and development of plant extracts for dyes industry, plant staining on organic or inorganic supports and laboratory and industrial developments of textile dyeing processes. paola croveri has a msc in chemistry and a phd in science for cultural heritage conservation. she was assistant lecturer at malta centre for restoration, now lecturer on contract at university of turin. research interests focus on deterioration and conservation of paintings, glasses, stones, textiles, vp-sem analysis. at ccr is today project manager for scientific innovation and research development. annamaria giovagnoli graduates in chemistry in 1978 and works as conservation scientist (chemist) at istituto superiore per la conservazione e il restauro (iscr, mibac) since 1983. she was the director of ccr’s scientific laboratories (2008-2014). her studies and projects focus in particular on the conservation of historical buildings, monuments and exhibits. she teaches “environmental chemistry for cultural heritage” at iscr school. anna piccirillo has a phd in chemical science at university of turin (2004) focused on the study of ancient binding media. since 2008, she works at ccr as conservation scientist (chemist). in the field of cultural heritage conservation, she dedicates herself to the characterization of materials with particular attention on modern and contemporary materials and on their degradation products. 72 cultura e scienza del colore color culture and science | 06 | 2016 | 71 79 cavaleri t. et al. issn 2384-9568 doi: 10.23738/ccsj.i62016.07 1. introduction within a european project a, centro conservazione e restauro “la venaria reale” (ccr, italy) in collaboration with couleurs de plantes (cdp, rochefort, france) and arrdhor critt horticole (critt, rochefort, france) recently experienced an eco-innovative application of natural dyeing in the conservation of an ancient tapestry. for integrating lacunae on historical tapestries, it is necessary to use textile fibres suitable for conservation dyed ad hoc in the requested colour. nowadays most of conservators use synthetic pre-metallized dyes, which contain heavy metals such as chrome and cobalt. the idea of testing eco-friendly products for dyeing arose from the necessity of protecting operator health and reducing environmental impact. on the other hand, synthetic dyes are very easy-to-use, as you can get requested colour in a one-step process, varying relative ratios of three primary dyes and their concentration in the dyeing bath. once fibres dried, they are readyto-use. since project started, we guessed that natural dyes, coming from different flowers and plants, would not behave at the same manner of synthetics and that colour reproduction would be more difficult. moreover, the use of natural dyes requires to treating the textile fibres preliminarily with a mordant, implying a twostep dyeing process [1]. the challenge was to offer to the conservators a complete palette of colours and recipes with natural products and with streamlined dyeing processes. colorimetric and spectrophotometric analyses provided useful data for studying behaviour and interaction of those products and for getting some colours – as a yellow, a green and a brown specifically requested in the conservation of a 17th century tapestry. 2. experimental and method among the colour triangles currently used by conservators as reference for dyeing, we considered the yellow, magenta and grey (ymg) triangle (figure 1). in this triangle, pre-metallized primary colours at the maximum saturation value lie at vertex and two-dye mixtures lie on the triangle sides. all the others are threedye mixtures. inside the triangle, relative ratios among dyes change with a 10% step from 0% to 100%, forming in total 66 colours (i.e. y:20%, g:50%, m:30%). as mentioned, operator can obtain simply further colours, since it is possible to change hue modifying dyes’ ratio and to change saturation varying dyes’ concentration in the dyeing bath. in the preliminary, practice part of the project, critt tried to reproduce the ymg triangle using natural dyes and non-toxic mordants produced by cdp and testing more than three hundred recipes. the set of recipes, simulating the 66 synthetic colours, contains old fustic, weld, madder, dyer’s broom, myrobalan, logwood, cochineal and alder buckthorn as dyes, and aluminium lactate, titanium oxalate, copper acetate, iron lactate, woad and gallnuts as mordants. as textile support, critt used commercial wool yards that are compact and elastic likewise the wool but more easily available. firstly, by means of colorimetric analyses we compared the colours of the original synthetic triangle to the natural ones made by critt and we recognized a critical area inside both the two triangles that means an area where colour deeply changes moving from one sample to the other. so, for completing the palette, it would be necessary to obtain in that area other intermediate colours. while the use and the matching of synthetic dyes give predictable colours, we supposed it would be difficult to obtain intermediate colours by using natural dyes, in that area above all. therefore, in the second phase of the research, we deepened the study about dyes and mordants’ behaviour by spectrophotometric and colorimetric analyses, aiming at individuating recipes that could integrate the set of references providing to the conservator a more complete palette. at the end, thanks to a general comprehension about mordants’ contribution to the textile fibres’ final colours, we could modify some critt recipes in order to reproduce on woolb samples precise colours, requested by the conservators for the tapestry’s integration. on these samples, we could evaluate by colorimetric analyses three important aspects: the influence of the different textile support on the final colour; the possibility of preparing fibres before (treating them with mordants in a previous separate moment), in order to offer to the conservators a faster and streamlined dyeing process; the colour fading and light stability of dyeing. colorimetric analyses were carried out by means of a spectrophotometer konica minolta cm700d that works in a d/8° optical geometry along a 400 nm to 700 nm wavelength range, with a 10 nm step resolution. the instrument was set to provide cielab 1976 (l*, a*, b*, c ab *) chromatic coordinates, where l* corresponds to lightness, a* from negative to positive corresponds respectively to the green or red component and b* from negative to positive corresponds respectively to the blue or yellow component, for standard illuminant d 65 . colour differences (δe 00 ) were calculated from those coordinates using the ciede2000 formula [2, 3]. 73 cultura e scienza del colore color culture and science | 06 | 2016 | 71 79 colorimetric and spectrophotometric analyses for an ecoinnovative application of natural dyeing in textile conservation issn 2384-9568 spectrophotometric analyses were performed in fibre optics reflectance spectroscopy (fors), using an ocean optics hr2000+es spectrophotometer and an ocean optics hl2000 halogen lamp, bounded by optical fibres of 400 µm in diameter, working in a 2x45°/0° geometry and collecting spectra along a 350 nm to 1000 nm wavelength range with a 0.5 step resolution. 3. research 3.1. synthetic and natural colour triangles comparing synthetic colour triangle to the one reproduced by critt with natural dyes, we did not find in general a perfect correspondence. in fact, the average δe 00 calculated between any sample and its reproduction with natural dyeing is around 19.7 and this is principally due to the different level of saturation. colours obtained from natural dyeing appear, in fact, more saturated, showing averagely lower l* values (average δl* critt-ymg : -17.8). anyway, this alone should not be a problem, since in general it is possible to weak the colour simply diluting the figure 1 one of the colour triangle of pre-metallized dyes based on yellow, magenta and grey (ymg) primary colours dyeing bath. for comprehending behaviours of synthetic dyes, we firstly focused on the three sides of the ymg triangle, where there are binary mixtures (ym, yg and gm), so working with two only variables. the first result was that the sides of the triangle behave as a sort of chromatic scale of equidistant colours, so representing a satisfying palette for the conservators, excluding the area near to the yellow vertex. in fact, δe 00 calculated between synthetic close samples show always low and homogenous values of around 3 units, but in that critical area: as shown in table 1, adding 10% of magenta or grey into pure yellow, δe 00 respect to yellow can rise up to 26 units. this means that operator can obtain almost all possible colours exploiting that palette, but he could probably obtain many other intermediate colours starting from pure yellow. considering critt samples simulating the triangle’s sides, one problem about the use of natural dyes emerges soon: δe 00 calculated between close natural samples (table 1) are high and non-homogenous, suggesting that operator samples of colours along the ymg triangle’s sides pre-metallized ym mixtures critt natural dyeing pre-metallized yg mixtures critt natural dyeing pre-metallized mg mixtures critt natural dyeing magenta % δe 00 between close samples δe 00 between close samples grey % δe 00 between close samples δe 00 between close samples grey % δe 00 between close samples δe 00 between close samples 0 0 0 10 19.2 19.1 10 26.3 12.4 10 5.2 6.2 20 11.3 12.2 20 9.2 21.3 20 4.1 11.3 30 5.1 11.4 30 6.4 14.5 30 2.2 7.4 40 4.3 6.3 40 4.1 5.1 40 2.1 3.3 50 1.2 7.2 50 3.2 50 2.3 4.1 60 3.4 7.3 60 3.1 18.2 60 2.3 5.2 70 2.1 15.3 70 3.1 5.4 70 2.1 4.2 80 2.2 7.2 80 2.4 6.1 80 2.4 5.3 90 2.4 2.2 90 2.2 4.1 90 1.2 4.1 100 3.3 3.4 100 2.1 3.2 100 1.3 3.2 table 1 trends of the δe 00 calculated between couples of close samples along the ymg triangle’ sides and between their respective couples of samples reproduced by critt with natural ingredients 74 cultura e scienza del colore color culture and science | 06 | 2016 | 71 79 cavaleri t. et al. issn 2384-9568 doi: 10.23738/ccsj.i62016.07 should not use them as a palette of equidistant colours. analysing a* and b* values, in fact, we noticed they have discontinuous trends all along the triangle’s sides (orange curves, figure 2). moreover, the problem of a critical area near yellow vertex exists also in the natural palette, as confirmed again by δe 00 values (table 1). those outcomes addressed us to deepen the research on natural yellow and green yellowish dyes and their behaviours. 3.2. natural dyes and non-toxic mordants behavior inside the collection of natural samples made by critt, many recipes contain more than one dye and/or more than one mordant. as mentioned, mordants used in the 66 colours that simulate the synthetic triangle are aluminium lactate, iron lactate, copper acetate and titanium oxalate. trying to understand their effect on the textile fibres’ final colour, we chose groups of samples dyed with one only dye, and treated with anyone of those mordant, with fixed values of concentrations. studying and comparing samples by means of colorimetric and spectrophotometric analyses, we could appreciate how mordants have some figure 2 trends of a* and b* values in pre-metallized dyeing along the triangle sides (blue curves) and respective reproductions made by critt with natural dyes (orange curves). distinct effects on the fibres’ final colour. in particular: • the the use of iron lactate as mordant makes the colour browner; • the use of aluminium lactate makes the colour lighter; • the use of titanium lactate or of copper acetate have a similar effect and colour is more or less intermediate in relation to the previous two cases; • copper acetate makes the colour a little bit greener, even if the greening effect is obviously less visible in green samples. for instance, inside the group of green samples, we did not individuate relevant colour differences that could be clearly ascribable to the different mordant. nevertheless, we could verify that iron lactate, in general, makes colour a little bit browner. table 2 and figure 3 relate to green samples dyed with chlorophyll: here, the use of aluminium lactate, copper acetate and titanium oxalate yield to the fibres the same colour as shown by chromatic coordinates -, while the textile fibres treated with iron lactate are browner, showing lower l* and a* values critt sample name critt recipe cielab 1976 chromatic coordinates mordant dyes l* a* b* 284 2% aluminium lactate chloropyll 1% 56.1 -9.5 16.0 285 2% iron lactate chloropyll 1% 52.9 -7.0 20.1 286 2% copper acetate chloropyll 1% 58.2 -9.3 17.8 287 2% titanium oxalate chloropyll 1% 58.2 -9.4 17.8 table 2 cielab1976 coordinates of samples dyed with chlorophyll, previously treated with four different mordants 75 cultura e scienza del colore color culture and science | 06 | 2016 | 71 79 colorimetric and spectrophotometric analyses for an ecoinnovative application of natural dyeing in textile conservation issn 2384-9568 figure 3 reflectance spectra of samples dyed with 1% chlorophyll, previously treated with four different mordants (blue curve: 2% alum lactate; red curve: 2% iron lactate; green curve: 2% copper acetate; orange curve: 2% titanium oxalate) critt sample name critt recipe cielab 1976 chromatic coordinates mordant dyes l* a* b* 345 2% aluminium lactate old fustic 2% 55.5 4.1 37.7 346 2% iron lactate old fustic 2% 35.8 3.6 19.0 347 2% copper acetate old fustic 2% 46.9 6.4 38.4 348 2% titanium oxalate old fustic 2% 50.7 9.7 40.9 table 3 cielab1976 coordinates of samples dyed with old fustic, previously treated with four different mordants critt sample name critt recipe cielab 1976 chromatic coordinates mordant dyes l* a* b* 156 2% aluminium lactate madder 2% 45.3 34.8 20.5 45 2% iron lactate madder 2% 32.7 10.3 9.3 158 2% copper acetate madder 2% 46.8 16.5 9.6 3 2% titanium oxalate madder 2% 43.3 25.7 15.6 table 4 cielab1976 coordinates of samples dyed with madder, previously treated with four different mordants and a higher b* value. on the other hand, their reflectance spectra are all comparable: in the four spectra, absorption bands are all aligned at the same wavelength suggesting they are due to the dye, while it is not possible to recognize any spectral characteristic directly ascribable to mordants. inside the wider group of yellow and yellowish samples, it is possible to observe by the naked eye that samples treated with aluminium lactate are the lightest ones while the ones treated with iron lactate are the darkest ones and appear browner. on the contrary, textile fibres treated with copper acetate and titanium oxalate appear quite similar, even if copper yield to a lightly greener colour. table 3 and figure 4 relate to yellow samples dyed with old fustic. in this case, colorimetric values give evidence of the browning caused by iron-based mordant, of the lightness caused by aluminium and of the greening (lower a* value) due to the copper, visible by comparing samples 347 and 348. reflectance spectra have, in fact, different behaviours, showing low reflectance values in the case of iron lactate treatment and higher values in the case of aluminium lactate, where it is also visible a flex at around 490 nm. differently from the case of chlorophyll, it seems impossible to recognize spectral characteristics clearly ascribable to old fustic inside the considered wavelength range. also concerning pink samples, the use of aluminium lactate gives the lightest result, while iron lactate makes the final colour browner and darker. as for green and yellow samples, titanium oxalate and copper acetate have similar effects on the final colour, even if you can distinguish lower a* and b* values in the case of copper based treatment. table 4 refers to the group of pink samples dyed with madder, reported as example of those chromatic behaviors. in figure 5, fors spectra of samples treated with aluminium-, copperand titanium-based mordants show characteristic and recognizable spectral behavior of madder [4, 5]. on the contrary, the use of iron lactate involves a deep flattening of the reflectance curve and a shift of the main flex (600 nm) towards longer wavelengths range, identifiable in the browning effect of the sample. the knowledge about the influence of different mordants in the final colour helped us in modifying some critt recipes, with the final aim of getting precise colors requested for tapestry’s conservation. 76 cultura e scienza del colore color culture and science | 06 | 2016 | 71 79 cavaleri t. et al. issn 2384-9568 doi: 10.23738/ccsj.i62016.07 starting colour of conservation wool seems not to have a relevant influence on the yarns’ final colour (δe 00 around 1). as table 5 shows, the two green samples of two different wools both treated with 2% iron lactate and dyed with 2% old fustic (recipe n° 46) have very similar chromatic coordinates, with a δe 00 of 1.2 units. the other example (recipe n° 50) relates to two grey samples, both treated with 2% iron lactate and dyed with 3% myrobalan, which show a δe 00 of 1 unit. 4.2. test on a streamlined dyeing process since all natural recipes require a two-step dyeing process the first one involving the treatment with mordants, the second one concerning the dyeing of the textile fibres while they are still wet we imagined a way for providing to the conservators a streamlined dyeing process, shortening the working time. the idea was to supply to the conservators textile 4. application 4.1. test on textile support as mentioned, critt had tested recipes on samples of commercial wool. since wool generally undergoes some chemical treatment as blanching or softening made with products such as silicon that can inhibit the dyeing – we reproduced some recipes as they are on restoration wool, in order to evaluate the influence of the textile support on the final colour. comparing colorimetric values of commercial and restoration wool yarns – as they are and when dyed with the same recipe – we could evaluate the colour difference. as reported in table 5, commercial wool not dyed is of a brighter white, probably because of some blanching treatment received during the production process, while the wool normally used for conservation, before the dyeing, is more yellow and a little bit darker, showing a colour difference (δe 00 ) of 19.2 units. nevertheless, the figure 4 reflectance spectra of samples dyed with 2% fustet, previously treated with four different mordants (blue curve: 2% alum lactate; red curve: 2% iron lactate; green curve: 2% copper acetate; orange curve: 2% titanium oxalate) figure 5 reflectance spectra of samples dyed with madder, previously treated with four different mordants (blue curve: 2% alum lactate; red curve: 2% iron lactate; green curve: 2% copper acetate; orange curve: 2% titanium oxalate) pre-metall. dyes ymg % natural dyes recipe n° critt – natural dyeing on commercial wool ccr – natural dyeing on restoration wool colour difference ciede2000 l* a* b* l* a* b* δe 00 (not dyed wool) 88.7 -0.4 10.5 83.8 0.62 12.8 19.2 y:70% m:10% g:20% 46 ccr 46 38.7 3.9 18.6 39.9 3.2 17.7 1.2 y: 60% m: 20% g: 20% 50 ccr 50 36.8 4.0 7.4 36.8 3.6 6.2 1.0 table 5 colour difference between commercial and restoration wool and effects on some dyeing’s final colour 77 cultura e scienza del colore color culture and science | 06 | 2016 | 71 79 colorimetric and spectrophotometric analyses for an ecoinnovative application of natural dyeing in textile conservation issn 2384-9568 fibres already treated with mordants at different levels of mordant concentration. as the mordant effect and its concentration are decisive in the final colour of textile fibres, conservators should use that set of fibres, differently pre-treated, for varying whatever recipe and obtaining different colours. for this reason, we had to verify if an interruption between the first and the second step of the dyeing process could have some effect in the final colour. comparing some samples dyed following the normal process to other ones dyed 28 days after the mordant treatment, the δe 00 results averagely of 1.4 units, confirming it is possible to interrupt the dyeing process without causing any relevant variation. 4.3. achievement of fitting colours requested for textile conservation the conservative intervention on the historical tapestry required textile fibres of some fitting colours, for integrating original areas that displayed some lacunae. as mentioned, most of colours requested were lightly different from the ones obtained by critt. the first work of colour finding involved a yellow: it was necessary to get a colour similar to the pre-metallized y 100% sample, but lightly darker and a little bit greenish. the y 100% sample had been reproduced by critt using 10% aluminium lactate as mordant and 5% old fustic with 5% weld as dyes. starting from that recipe, we modified dyes’ concentration “colour finding”: yellow ccr sample name dyeing recipe cielab 1976 colour difference ciede2000 relative to the original tapestry mordant dyes l* a* b* δe 00 original tapestry 43.7 9.4 32.5 ccr 1 10% aluminium lactate 5% old fustic 5% weld 64.5 4.9 54.7 23.8 ccr 1b 10% aluminium lactate 6% fustet 3% weld 66.0 4.8 57.6 25.4 ccr 1d 10% aluminium lactate 0.5% iron lactate 10% fustet 54.3 3.7 49.0 15.6 ccr 1e 10% aluminium lactate 0,5% iron lactate 1% titanium oxalate 10% fustet 51.9 15.6 54.7 11.2 ccr 1f 8% aluminium lactate 1% iron lactate 10% fustet 47.2 3.2 39.9 8.6 table 6 schema of the cielab1976 chromatic coordinates measured on a yellow area of the historical tapestry, compared to some samples made by ccr using natural dyes and non-toxic mordants modifying critt recipe “colour finding”: grayish brown ccr sample name dyeing recipe cielab 1976 colour difference ciede2000 relative to the original tapestry mordant dyes l* a* b* δe 00 original tapestry 26.0 3.6 8.9 ccr 49 2% iron lactate 1% old fustic 1% madder 34.2 6.6 11.6 7.2 ccr 49b 5% iron lactate 5% madder 5% fustet 23.3 7.3 8.6 4.7 ccr 49c 5% iron lactate 10% old fustic 1% madder 28.7 5.1 14.5 4.4 ccr 49d 5% iron lactate 8% fustet 2% madder 24.6 6.0 11.6 3.0 table 7 schema of cielab1976 chromatic coordinates measured on a grayish brown area of the historical tapestry, compared to some samples made by ccr using natural dyes and non-toxic mordants modifying critt recipe. “colour finding”: green ccr sample name dyeing recipe cielab 1976 colour difference ciede2000 relative to the original tapestry mordant dyes l* a* b* δe 00 original tapestry 43.1 4.4 17.9 ccr 46 2% iron lactate 2% fustet 39.9 3.2 17.7 3.1 ccr 51 1% iron lactate 1% copper acetate 1% fustet 1% weld 46.79 1.79 30.64 9.7 ccr 51a 2% iron lactate 1% fustet 1% weld 40.9 3.4 18.7 2.4 table 8 schema of the cielab1976 chromatic coordinates measured on a green area of the historical tapestry, compared to some samples made by ccr using natural dyes and non-toxic mordant modifying critt recipe 78 cultura e scienza del colore color culture and science | 06 | 2016 | 71 79 cavaleri t. et al. issn 2384-9568 doi: 10.23738/ccsj.i62016.07 as shown in table 6, adding also iron lactate to get the browning effect: sample ccr 1f fitted well the requested colour and it was used for the textile conservation. after that, we worked on a grayish brown colour: in this case, the most similar synthetic sample was a three-dye mixture made with y:60%, m:20% and g:20%. its reproduction with natural ingredient contained 2% iron lactate as mordant and 1% old fustic and 1% madder as dyes. since conservation required a browner colour, we firstly added iron lactate to the mordant, increasing contemporarily dyes quantities (sample 49b, table 7). while iron mordant had given the desired effect to the colour, probably the increasing of madder carried it towards a too red hue. therefore, we modified again dyes ratios finding at the end a suitable colour for conservation. table 8 shows other examples about green colours. the first (ccr 46) is one of the cases in which the recipe gave a good correspondence with the green original tapestry area, so that conservator could exploit the recipe as it is. the second case is about the recipe made with old fustic and weld, and with iron and copper-based mordants (ccr 51), in which we could get the right colour varying mordants (see ccr 51a, table 8). 4.4. light-stability evaluation of dyed samples in order to verify the light-stability of the natural ingredients we used, we submitted all dyed samples to an accelerated ageing by means of a controlled light exposure. we used a camera sun-test cp equipped with a xenon lamp (1500 w) that provides an irradiation of about 750 w/m2; a filter cuts the wavelength range under 320 nm, aiming at simulating the solar light indoor exposure of samples through a window. table 9 shows some representative dyed samples, reporting their chromatic coordinates and the colour differences calculated before and after the light exposure. the result was that samples underwent a feeble discoloration after 24 hours exposure, suggesting they can be used for restoration. 5. conclusions in the field of textile conservation, most of conservators now use synthetic pre-metallized dyes, which contain heavy metals such as chrome and cobalt. all tests made within this project on eco-friendly products for dyeing, risen from the necessity of protecting operator health and reducing environmental impact, allowed to provide an efficient alternative for dyeing. using natural dyes (old fustic, weld, madder, dyer’s broom, myrobalan, logwood, cochineal and alder buckthorn) and non-toxic mordants (aluminium lactate, titanium oxalate, copper acetate, iron lactate, woad and gallnuts) produced by cdp, in fact, critt prepared with different recipes a wide set of coloured samples, that can be used as a new reference palette for dyeing. moreover, the spectrophotometric and colorimetric study about mordants, carried out at ccr, provided useful indication for comprehending how to modify recipes whenever the conservative intervention requests further colours. for those cases, it should be even possible to equip conservation laboratories with textile fibres pre-treated with mordants at different values of concentration: therefore, the dyeing process at the expense of the conservator would be also extremely streamlined. thanks to this project, a yellow, a green and a brown obtained by modifying some critt recipes were used by conservators to integrate lacunae of a 17th century tapestry. on the other hand, fors spectra collected on more than three hundred samples represent now a new database on which to deepen the research, also by means of other spectroscopic techniques, in order to use data as diagnostic tool for future investigation. ccr sample name cielab 1976 chromatic coordinates before light exposure cielab 1976 chromatic coordinates after 24 hours of light exposure colour difference ciede2000 before and after light exposure l* a* b* l* a* b* δe 00 ccr 46 42.6 3.5 18.0 44.7 4.0 18.3 2.0 ccr 51 54.1 1.6 28.7 54.2 3.1 27.5 1.8 ccr 51a 46.3 3.4 17.7 47.8 4.5 18.9 1.7 ccr 1f 54.0 17.2 54.8 51.5 15.2 46.6 3.8 ccr 49 36.2 6.5 10.8 37.7 6.5 12.8 2.1 ccr 49b 25.8 7.2 8.5 27.8 6.5 9.5 1.9 ccr 49c 30.9 6.9 13.4 30.9 6.5 12.8 0.5 ccr 49d 29.4 6.3 12.4 31.3 6.7 13.2 1.6 table 9 colour differences δe 00 measured on some samples after 24 h of uv exposure 79 cultura e scienza del colore color culture and science | 06 | 2016 | 71 79 colorimetric and spectrophotometric analyses for an ecoinnovative application of natural dyeing in textile conservation issn 2384-9568 notes a innocolors crosstexnet era-project 2011 “study of stability of traditional natural dyes and their interaction with textile fibers in comparison with new natural dyes and new dye techniques, applicability to industrial production and restoration of ancient textiles”. b wool weave yards be-mi-va, title 2/22 nm, colour 27666 15/00351 bibliography [1] d. cardon, “natural dyes”, archetype publication, 2007. [2] c. oleari, “misurare il colore”, hoepli, 2008. [3] r. johnston-feller, “color science in the examination of museum objects”, the getty conservation institute, 2001. [4] c. bisulca, m. picollo, m. bacci, d. kunzelman, “uv-visnir reflectance spectroscopy of red lakes in paintings”, 9th international conference on ntd of art, jerusalem israel, may 2008. [5] c. montagner, m. bacci, s. bracci, r. freeman, m. picollo, “library of uv-vis-nir reflectance spectra of modern organic dyes from historic pattern-card coloured papers”, elsevier, 2010 funding this work was supported within por fesr 2007-2013 axe 1 activity i.1.3., crosstexnet era-net transnational call 2011 (20122013). conflict of interest no financial/personal interest have affected the authors’ objectivity. the authors claim that no potential conflicts exist. cultura e scienza del colore color culture and science 7 cultura e scienza del colore color culture and science | 10 | 2018 issn 2384-9568 1meriem benkhedda meriembenkhedda@univ-usto.dz 2kheira tabet aoul kheira.anissa@uaeu.ac.ae [corresponding author] 1département d’architecture, université des sciences et de la technologie d’oran mohamed boudiaf, usto-mb, oran, algeria 2 department of architectural engineering, college of engineering, united arab emirates university, pobox 15551, al ain, united arab emirates color on ceramics in the medieval architecture of tlemcen, algeria: light, ambiance and symbolism abstract the architectural heritage of the marinid and ziyanid dynasties in the region of tlemcen (algeria) is characterized by geometric and floral shapes of the ornamental ceramic of particularly rich polychromic expressions. this ornamentation defines the minarets, porches, interior courtyards and patios. the ceramic colors in different tones and arrangements provide spaces with an exceptional quality that highly characterizes this medieval arab architecture. the polychromic compositions of the ceramic with their intrinsic spatial and aesthetical value remain largely unexplored. this research attempts to explore first, an untapped ancestral know-how or “savoirfaire” and second, to demonstrate that this architectural heritage has a colorful atmosphere, whose evolution is linked to the relationship between shapes, lights, materials and colors as well as its socio-cultural context. the investigation method consists of a survey of colors on ceramics and an analysis of arrangement patterns between colors and geometry (relationship and mixtures of colors) to determine the rhythms, harmonies of figures and background, optical compositions, and finally determine the color language and agreements that result. color properties, the subtle combination of colors and materials interacting with an exquisite geometry display a decisive influence on the appearance and the ambiance that emerge, providing brightness and light, creating rhythm, motley and fusion in a web of optical effects, filled with symbolism, suitable for the cultural and religious circumstances of the place. keywords color, ceramic, marinid, architecture, ambiance, tlemcen, algeria. citation: benkhedda m. and tabet aoul k. (2018) ‘color on ceramics in the medieval architecture of tlemcen, algeria: light, ambiance and symbolism’, cultura e scienza del colore color culture and science journal, 10, pp. 07-12, doi: 10.23738/ccsj.i102018.01 received 15 september 2017; revised 07 june 2018; accepted 30 november 2018 meriem benkhedda is an architect and phd candidate and is currently teaching plastic and graphic art in the architectural program at the university of science and technology of oran, algeria. she specializes in color theory and application in the built environment in general with a focus on islamic architectural heritage in the maghreb kheira tabet aoul is a professor of architecture at the united arab emirates university, uae. she draws from over 25 years of international academic and professional experience in algeria, usa and the middle east. her research focuses on green buildings, sustainable heritage conservation and human factors in the built environment. 8 cultura e scienza del colore color culture and science | 10 | 2018 | 07 12 benkhedda m. and tabet aoul k. issn 2384-9568 doi: 10.23738/ccsj.102018.01 1. introduction the northwestern part of algeria and in particular the region of tlemcen is one of the few places in algeria that still has major representative monuments of arabic art. the region of tlemcen in western algeria displays an art that truly reflects the splendor of the arab civilization through its successive dynasties. its proximity to morocco and spain explains the presence of many relics and monuments of islamic art from the thirteenth and fourteenth centuries, contemporary of those found in granada and fez. its architecture attests of a thriving arts production. “one should be pleased to admire what remains of the great royal city and jealously preserve its admirable remains” (marçais & marçais, 1903, p.10). the city of tlemcen owes its embellishments to its successive dynasties; the almoravids, the almohads, the zianides and most particularly the marinids (bourouiba, 1981). tlemcen’s monuments, which span from the thirteenth to the middle of the fourteenth centuries, are contemporary to the great monuments of granada in spain. they form a group of building sassociated with a period of full development of the andalusian architectural style. during their quarter-century long reign over the city, the marinids endowed tlemcen of its most beautiful monuments, including sidi boumediene compound, the sidi’l-halwi mosque, and the entire city of el-mansourah, of which, unfortunately only the main mosque’s minaret remains. one of the elements that established the refined ornamentation of such buildings is the scenery flat polychrome inlaid glazed pottery called mosaic of faience, accompanied by stucco and wood decoration. comparatively, the zianides dynasty produced sidi belahcen mosque, the mechouar mosque, palace, and a school, the madrassa taschfiniya. zianides’ architecture is adorned with ceramic and polychrome earthenware mosaics. the main sections of the faience mosaic (also referred to as zellij) are cleverly juxtaposed and combined. they generally cover the bases of walls, floors of courtyards, porches and doorframes as well as the top parts of minarets. the surfaces garnished with ceramics are the most colorful and the best preserved ones. the art of color is superimposed on the ceramic with geometric and floral arabesques forms. the design of lines is mixed with that of the colors to provide the place with a special atmosphere, highlight its architecture and its spatial and architectural details. in fact, these materials conceal a rough masonry work, made of rammed earth or unfinished bricks and provide an appearance of prosperity. “the surfaces appear to be luxuriously adorned immediately evoking the taste of the muslim aristocracy” (clévenot & degorge, 2000, p.96). the geometry of the patterns and the fractals of this important heritage have been widely studied. comparatively, little has been done in terms of the study of color design and arrangements. the objective of this work is to fill this gap. in the present study, the analysis is restricted to a single monument where the polychrome of its different pieces is explored. the relatively well-preserved architectural ensemble of sidi boumediene was selected for this study as the polychrome ceramics is widely used. other relevant monuments, such as the madrasa tachfiniya have been completely destroyed (kouma & nafa, 2003), only remain statements made by earlier french architects of historical monuments, or some ceramics exhibited in the museum tlemcen. the investigation methodology of the present study is based on a chromatic analysis of the arrangements of colors and their derived psychological and symbolic meanings. conceptions. 2. sidi boumediene compound the sidi boumediene compound, located in the neighborhood of el eubbad in the city of tlemcen, was built in honor of abu choaïb madyane (boumediene) el andaloussi, a teacher, writer and poet and pole of the sufism doctrine in algeria and the maghreb. the architectural ensemble includes the sidi boumediene mosque, built in 1339 (739 ah) by the marinid sultan, abu hassan ali. it also includes the tomb of saint sidi boumediene located nearby, and a madrasa (religious school) built in 1347 (bourouiba, 1981). it is the flourishing ornamentation, mainly flat ceramic décor that makes this building stand out as a remarkable heritage. indeed, the entrance to the mosque is made from a monumental porch, with a seven-meter high horseshoe arch, covering a staircase which leads to the door of the mosque. on the front porch, a triple festoon of brick inlaid with enamel of green netting, divides the frame into two parts: the first, the keystone, formed by a large circular border round the hanger, the second is formed by two spandrels. the finishes of this framework, the amounts that support it and the spandrels, are made by arabesques, floral decor with double palm interlaced, regularly repeated, in mosaic tiled in four tones; white, brown, green and yellow iron, framed by a green tone ceramic net. an epigraphic band in black on white background, dedicated to sultan abu al-hassan, is written above the rectangular frame. the frieze which crowns the portal is decorated 9 cultura e scienza del colore color culture and science | 10 | 2018 | 07 12 color on ceramics in the medieval architecture of tlemcen, algeria: light, ambiance and symbolism issn 2384-9568 with inlaid bricks of brown enamel plates and green bands above five radiating eight point rosettes. the intrados of the arch carries a regular geometric white, yellow and brown ocher coating. eleven steps allow access to this porch and provide this arcade with a majestic base. the stair risers are covered with diamond-shaped multicolored ceramics which continues through the floor with polychrome faience. the subtle ornamentation porch marks the threshold giving access to an introvert interior; the square courtyard of the mosque, limited by the arch of the prayer hall in front of the main entrance, embellished with a beautiful onyx basin for ablutions. this courtyard, similar to that of the madrasa of sidi boumediene (religious school), is covered with mosaics, much less complex than the ornate porch. the ceramic is composed with small diamonds of various colors. tiles are assembled side by side and arranged diagonally in rows of diamonds of the same nuance. they are also set in bands through an arrangement of tones: manganese brown, copper green, iron yellow and white. the diagonal bands, joined to each other form a checkerboard, thus highlighting a grid floor. just as the porch and the door frame, the minaret, located at the northwest corner of the mosque, is richly decorated with a polychrome mosaic. a frieze of inlaid ceramic with large rosettes, result of a geometrical interlacing and star polygons, delineates its upper part. 3. chromatic analysis in tlemcen, ceramic is represented by pavement tiles with stamping and by multicolored tiles on stanniferous enamel. the pigments as described and classified by marçais (1903) are as follows: • white: beautiful dough, half-matt, slightly greenish, very little cracks • manganese brown: generally used very thick, as to form an almost black tone. • yellow is iron yellow, rather impure, and produces a tan and spotted yellow. • copper green has an intrinsic value and a very variable tone; in the same decor it can appear as very dark and very deep, or very clear leaning towards celadon or turquoise colors. figure 1 (left) monumental porch of sidi boumediene mosque, covering a staircase with eleven steps covered with multicolored diamond-shape ceramics. source: authors. figure 2 (right) the front of the porch with a triple festoon of bricks inlaid with enamel of green netting. the finish is highlighted by a four-tone floral decor. a majestic frieze ornates the upper part of the entrance porch source: http://www.vitamineca. c o m / m o b i l e / p h o t o g m . php?p=articles/205/205935.jpg figure 3 geometric design of the underside of the arch, with a lightdark contrast and a floral decoration of the arch front. source: left: authors, right: watercolor by duthoi 1872 (authorized by © ministère de la culture (france), the médiathèque de l’architecture et du patrimoine (paris)) 10 cultura e scienza del colore color culture and science | 10 | 2018 | 07 12 benkhedda m. and tabet aoul k. issn 2384-9568 doi: 10.23738/ccsj.102018.01 • the cobalt blue is quite rare; it does not seem to have been used in tlemcen before the second half of the sixteenth century. it is clear and almost pure. this mosaic tile, in the form of enameled clay, is an assembly of varnished pieces with different tones, cut according to a template and recessed into each other. these pieces are molded, cooked and then coated with enamel and annealed again. they are adjusted, arranged and placed in cardboard decorations plans established beforehand. they are finally assembled and connected together with a mortar made of lime and sand, to form large plates of approximately half a meter, which are then fixed on the wall (marçais & marçais, 1903). 3.2 the porch a flat polychrome setting highlights the grandeur of the porch and announces the mosque with cursive writing and a combination of intertwined leaves and stems in a set of curves and counter curves. the tones used are a very dark brown (almost black), green, and tan-yellow, all on a white background. a green ceramic band underlines the arch, scalloped bricks and other details of the porch. this clever combination of ornamental flora symbolizes the infinite nature devoid of a center (burckhardt, 1985). for a muslim, these forms are patterns whose repetition extends beyond the visible material world; they are an expression of spirituality. islamic decoration is the least naturalistic art possible. the religious requirements prohibiting human representation left a free hand to the arab artists, to use the imitation of plants (marçais, 1903). this spirituality continues beyond the form, towards the world of colors. indeed, the koran often contrasted white to black (ringgenberg, 2009) as two contradictory elements of a same pair; light and darkness, day and night, shadow and light etc. in this floral composition, the color contrast is very pronounced, creating a raised pattern effect: the floral decor in dark brown seems to stand out from its white background (color contrast between advancing and receding colors). the clear-obscure (or chiaroscuro) is needed to develop not only a sense of proportions, but also the connection between the dark form thought as positive and the negative white. for painters, white and black are the strongest means of expression for light and darkness (itten, 1961). from the point of view of their effects, white and black are totally opposed. this type of contrast is also expressed in the arabic calligraphy here, white is the color of the visible light and black is the shadow that materializes interception of this light, including that of the sun, representing a relaxing protection from solar heat. it is part of the enjoyment in paradise, which explains the desire to create light and shadow effects. yellow and green colors are transitional colors between white and black. they are also intermediate values. the floral decoration is related to vegetation and to the garden of bliss promised to the muslim (clévenot & degeorge, 2000). this explains the use of the double palm in green tone arranged with the black infinite rod that extends throughout the decor. in islam, green is the color of the vegetation, color of the eternity garden of fruit trees, of green silk clothes, of different brocade sofas and carpets of paradise. the green color is eternal in the afterlife, but ephemeral on earth. the aim was to fill the surfaces with skillful combinations, by repeating various forms of ornamental plants. the yellow palm leaf placed near the brown one (nearly black) is added to the floral composition of the porch, which affirms the clear-obscure contrast. here the yellow color illuminates the chromatic ensemble. it replaces gold, gild and spark. it represents the energy and the wealth of the marinid dynasty. in our case study, yellow is similar to the color of the brick and thus, creates harmony. in this composition, the complementary shapes are coupled to an opposition between two values or two colors: black and white, raw brick and glazed brick, whose function is to disrupt the relationship between form and background. white on black draws the lines of the pattern. this combination of shapes and colors allows the transformation of the architectural context into a living and significant space. geometric patterns are combined with floral decoration. for example, on the surface of the underside of the arc, there is a very pronounced oblique weft, creating brown diamonds with identical shapes, which have the added geometric particularity to fit together. these nearly black surfaces are surrounded by yellow bands. their composition is based on a clear/ obscure contrast, creating a play of light and shadow and a set of relief. at the same time, this combination of tone indicates a quality design, which is the contrast between the saturated and bright yellow and the dull brown; de-saturated with the black. this would only accentuate the brightness of yellow and gives it the brilliant effect of the gold color (the marinids always wanted to represent the golden color). this panoply of colors enhances and enriches the white plaster. it creates frames design, light and shadows effects that animate the arc, into a directory of mathematical techniques. also, symbolically, the ornamental abundance means prosperity. 11 cultura e scienza del colore color culture and science | 10 | 2018 | 07 12 color on ceramics in the medieval architecture of tlemcen, algeria: light, ambiance and symbolism issn 2384-9568 3.2 the mosque and madrasa pavement but more than vegetation, geometry gives rise in the islamic context to an ornamental exploitation that does not have its equivalent anywhere else (clévenot & degeorge, 2000). first, stair risers of the stairs leading to the door of the mosque are decorated with small multicolored diamonds, whose tones are identical to the porch colors; green, black (dark brown) yellow on white background, all framed by a green ceramic surround. these fragments in diamond, smaller than those which adorn the courtyard of the mosque and the madrasa, pleasantly decorate the staircase. the gridded ground with fillets of diamonds is a formal system, where the geometry associated with the color plays in counterpoint and highlights the fountain in the middle of the patio. the diamond headbands are spread over the entire surface of the courtyard and create a grid of alternating colors. constructors have made a color scheme of bright and dark tones with this surface area (yellow and white with black), by creating a frame, like weaving or basketry. much variation on the principles of the frame has interesting similarities with the textile arts (clévenot & degeorge, 2000). with bands of dark diamonds, lines print their path on a background of white diamonds. the combinational logic of colors inside this frame creates visual effects. contrasting colors (black, white and yellow) accentuate the design of both frames and patterns. the results are optical phenomena of vibration because the eye is often undecided between clear and dark forms. the frame is a linear geometric distribution of these compositions, resulting in a network combination. for the viewer, the visual result is a moving and dynamic space, enlightened by white, illuminated by yellow, punctuated by green. black serves to emphasize and express these nuances. this polychrome geometric pattern possesses obviously, as those already mentioned, a symbolic value given to this highly allegorical place of the mosque. indeed, the chromatic whole, punctuated by a green color, introduces the concept of the garden, a glittering garden (with the use of yellow; color of gold and sparkle, of sun and its reflections) to represent the garden of eden. this mode of expression enhances the connotation, not the denotation, leaving the viewer with free rein in his interpretation. 3.3 the minaret the minaret rises majestically above the architectural complex of sidi boumediene. this is one of the prettiest still-standing specimens of its kind; by the synchronism of its proportions, the variety of its toppings and finally, in order to be perceived; the richness of ceramic coating that decorates its top (marçais & marçais, 1903). the tile mosaic that adorns this pinnacle is composed of each side by a frieze of four rosettes of rich geometrical construction. decorative rosettes scheme has a symbolic value, where polychrome stars (bright yellow, bypassing black tips, outlined by white) are laden with celestial meanings; a dark starry sky. the clear-obscure contrast is repeated. it emphasizes the spark of yellow, which forms a bright spot in the dark surface that surrounds it. to clarify the reading of the figures, the artist can assign to each element a different color. but he figure 4 the courtyard of sidi boumediene mosque, with a polychrome mosaic of faience (brown, yellow, green and white). source: author. figure 5 minaret of the mosque with a geometric and polychrome decor of rosettes. source: left: watercolor duthoi 1872 (authorized by © ministère de la culture (france), the médiathèque de l’architecture et du patrimoine (paris)). right: authors 12 cultura e scienza del colore color culture and science | 10 | 2018 | 07 12 benkhedda m. and tabet aoul k. issn 2384-9568 doi: 10.23738/ccsj.102018.01 can also disrupt the reading by playing on the simple alternation of light and dark (clévenot & degeorge, 2000). this abundant décor creates a sense of unreality faced with the material reality of the monument, making it a pure decor, a heavenly dream, a secluded place from worldliness. a row of crenellations crowns the main body of the tower; they carry a mosaic decoration unfortunately impacted by the elements. this is an adornment consisting of white stars on a black background. the use of the bright star pattern (white on a black background) is the incarnation of the celestial world. the pattern stands out as a white active form on a dark background, thus highlighting it. bands of green tones underline the architectural style. with the clear-obscure contrast, the entire surface takes a plastically animated feature 5. conclusions earthenware mosaics played an important role in the decoration of the medieval arab architecture of tlemcen. its proven resistance to elements made it the best exterior coating. permanent colors are fixed to the portals, minarets, inside courtyards spaces and mosques. colors are used in isolated fragments or small groups, and encrusted in a brick apparatus, as an exterior finish or shaped stone. the tones are bright spots in the matt or dark surfaces that surround them. they are either assembled in bands of a single tone highlighting architectural lines and facilitating formal reading, or into complete panels, composed of interlacing geometric, floral designs, mostly on white background. color gradients that suggest the volumes have been replaced by a play of contrasting oppositions, reflecting a more graphic understanding of the form (clévenot & degeorge, 2000). the visual impacts of these adorned spaces are intimately related to the magnificent adorning which covers them. indeed, polychrome ceramics transform the look of the architectural space. it has a decisive influence on the appearance of a building and the atmosphere that emerges, giving an identity to its geometric composition. this ceramics adorning the flat surfaces and its colors in chiaroscuro contrast provide the impressions of relief; form and substance effect; light and darkness… the use of color deliberately destabilizes a static geometrical design by introducing a new dynamic in architecture (blair & bloom, 2011). furthermore, each color symbolizes a state of fact in our world on earth or in the hereafter, combining psychology and physiology. this ornamentation carries aesthetical, philosophical and symbolic connotations. the image of this architecture, its aesthetic and its polychrome is a visual memory that characterizes the built heritage, a testimony of a know-how of previous civilizations. this study aimed to document in order to preserve this wealth and avoid the trivialization and degradation of some of the most remarkable architectural typologies of the country that can translate into a new design language and a positive contribution to the architectural realm. funding this research did not receive any specific grant from founding agencies in the public or not-for profit sectors. conflict of interest the authors declare that nothing affected their objectivity or independence and original work. therefore, no conflict of interest exists. bibliography blair, s., & bloom, j. (2011). and diverse are their hues: color in islamic art and culture. new haven and london: yale university press. bourouiba, r. (1981). l’art religieux musulman en algérie. 2nd edn. alger: sned. burckhardt, t. (1985). l’art de l’islam, langage et signification. paris: editions sindbad. clévenot, d., & degeorge, g. (2000). decor d’islam. paris: editions citadelles et mazenod. degeorges, g., & porter, i. (2001). l’art de la céramique dans l’architecture musulmane. paris: flammarion. itten, j. (1961). the art of color. new york: van nostrand reinhold company. kouma, a., & nafa, c. (2003). l’algérie et son patrimoine. paris: monom, editions du patrimoine. marçais, g., & marçais, w. (1903). les monuments arabes de tlemcen. paris: albert fontemoing editeur. ringgenberg, p. (2009). l’univers symbolique des arts islamiques. paris: l’hamattan. h t t p : / / w w w. v i t a m i n e c a . c o m / m o b i l e / p h o t o g m . php?p=articles/205/205935.jpg cultura e scienza del colore color culture and science 7 cultura e scienza del colore color culture and science | 06 | 2016 issn 2384-9568 1fabio colonnese fabio.colonnese@uniroma1.it 1department history, drawing, and restoration of architecture chromatic gradation as a symbolic and spatial device in the european context: piero bottoni’s cromatismi architettonici abstract in 1926, the young piero bottoni painted a series of watercolor studies entitled cromatismi architettonici. they are almost unique in the italian urban studies, proposing color gradations as a key to “symphonic” orchestrating the redevelopment of urban street fronts. this article puts bottoni’s proposal in relation not only to le corbusier’s contemporary research, with whom he had a correspondence, but also to some contemporary experiences in europe concerning the use of color gradations in architecture. later, it analyzes the watercolor perspectives, the far-from-ideal city to which they were addressed and their potential illusory and regenerative outcomes. finally, this article proposes a digital edition of the drawings, by means of a color interpretation procedure that provides the basis for an application of cromatismi on a portion of the urban facades of via roma, milan. this result, obtained through chromatic treatments of a photography, not only explicit the visual outcomes of cromatismi in a photographic vision but it highlights a number of technical and operational issues that would have strongly affected the realization of such a color project. nevertheless, time has proven that many of bottoni’s intuitions were valid for the purpose of color plans, occasional redevelopment of slums and precise perceptual effects in architecture. keywords piero bottoni, cromatismi architettonici, color plan, perception of architecture, digital photography model, chromatic gradations in architecture citation: colonnese f. (2016) ‘chromatic gradation as a symbolic and spatial device in the european context: piero bottoni’s cromatismi architettonici’, cultura e scienza del colore color culture and science journal, 06, pp. 07-22, doi:10.23738/ccsj.i62016.01 received 25 november 2015; revised 30 may 2016; accepted 30 september 2016 italian translation provided: ‘la gradazione cromatica come dispositivo simbolico e volumetrico nel contesto europeo: i cromatismi architettonici di piero bottoni’ fabio colonnese is architect, draftsman and ph.d. in drawing and survey of architectural heritage at sapienza university of rome, italy, where he also taught geometry, survey and drawing of architecture. he wrote il labirinto e l’architetto (2006), movimento percorso rappresentazione (2012), and a number of articles on the topic of representation of architecture, city, and landscape. 8 cultura e scienza del colore color culture and science | 06 | 2016 | 0722 colonnese f. issn 2384-9568 doi:10.23738/ccsj.i62016.01 there is another kind of perspective which i call aerial, because by the difference in the atmosphere one is able to distinguish the various distances of different buildings when their bases appear to end on a single line, for this would be the appearance presented by a group of buildings on the far side of a wall, all of which as seen above the top of the wall look to be the same size; and if in painting you wish to make one seem farther away than another you must make the atmosphere somewhat heavy.[…] and as a consequence of this rule it will come about that the buildings which above a given line appear to be of the same size will be plainly distinguished as to which are the more distant and which larger than the others. leonardo da vinci, of aerial perspective [1] 1. introduction in 1927, the twenty-three years old piero bottoni exhibited six watercolor studies entitled cromatismi architettonici at the iii exhibition of decorative arts in monza, at the kunstgewerbe museum in zurich and, a year later, at the famous italian exhibition of rational architecture in rome [2]. the drawings were illustrating new criteria for coloring of building fronts by using gradations able to visually interpret their architectural values and make them instruments for a symphonic urban perception (figure 1). in the text accompanying their publication in architettura e arti decorative, he claimed he was “convinced that the ‘volumetric’ function of color has never been sufficiently studied and, on the other hand, the ‘mass-volume’ value awarded by a color in a geometric solid has a great function in aesthetic balancing and in appreciation of ‘resistant’ values of each structure” [3]. thus, bottoni interpreted the facades of the buildings of his “ideal city” as abstract urban scenes available to demonstrate the semantic potential of his pragmatic and ambitious project. in december 12th, 1927 bottoni sent to le corbusier the results of his research on color and the swiss master replied with a letter full of compliments for the scientific approach and his “constructive” use of color. despite his young age, bottoni needed to measure its polychrome intuition with an interlocutor who was innovative in the european scene. this episode is revealing of his desire, if not necessity, for finding a place in the european context, as indeed he did along his long career, by taking part to ciam and many other international events. “evvi un’altra prospettiva, la quale chiamo aerea imperocché per la varietà dell’aria si possono conoscere le diverse distanze di varî edifici terminati ne’ loro nascimenti da una sola linea, come sarebbe il veder molti edifici di là da un muro che tutti appariscono sopra l’estremità di detto muro d’una medesima grandezza, e che tu volessi in pittura far parer più lontano l’uno che l’altro; è da figurarsi un’aria un poco grossa. […] e questa regola farà che gli edifici che sono sopra una linea parranno d’una medesima grandezza, e chiaramente si conoscerà quale è più distante e quale è maggiore dell’altro.” leonardo da vinci, della prospettiva aerea [1] 1. introduzione nel 1927 il ventitreenne piero bottoni, non ancora laureato, espose sei studi ad acquarello dal titolo cromatismi architettonici alla iii mostra delle arti decorative di monza, al kunstgewerbe museum di zurigo e, l’anno dopo, anche a roma, alla celebre esposizione italiana di architettura razionale [2]. i disegni illustravano nuovi criteri di colorazione dei fronti edilizi mediante l’utilizzo di gradazioni cromatiche in grado di interpretare visivamente i loro valori architettonici e di metterli a servizio di una percezione urbana sinfonica (figura 1). nel testo che accompagna i disegni su architettura e arti decorative, egli si dice “convinto che la funzione ‘volumetrica’ del colore non sia stata mai sufficientemente studiata e che, d’altra parte, il valore di ‘massavolume’ attribuito da un colore a un solido geometrico, abbia una funzione grandissima nell’equilibrio estetico e nell’apprezzamento dei valori ‘resistenti’ di ogni struttura”. [3] così bottoni interpretò le facciate degli edifici della sua “città ideale” come astratte quinte urbane disponibili a dimostrare le potenzialità semantiche del pragmatico quanto ambizioso progetto. il 12 dicembre 1927 bottoni inviò a le corbusier gli esiti della sua ricerca cromatica e il maestro svizzero gli rispose con una lettera piena di complimenti per l’impostazione scientifica e per l’uso costruttivo del colore. nonostante la sua giovane età, bottoni sentì quindi il bisogno di confrontare la sua intuizione policroma con un interlocutore tra i più innovatori del panorama europeo, rivelando da subito il desiderio, se non la necessità, di trovare per il suo lavoro una collocazione nel contesto europeo, come del resto farà per gran parte della sua carriera, partecipando ai ciam e a molti altri eventi internazionali. 9 cultura e scienza del colore color culture and science | 06 | 2016 | 0722 chromatic gradation as a symbolic and spatial device in the european context: piero bottoni’s cromatismi architettonici issn 2384-9568 2. chromatic gradation in the european architecture in the twenties european architecture, the debate on color took place mainly out of italy, in distant environments animated by the avantgarde desire to revolutionize the appearance and efficiency of the city. to le corbusier, bottoni’s urban polychromie could not be dissociated from new architectural composition criteria without reducing to an otherwise simple corrective, a superficial remedy against “the arbitrariness that governs the construction of the current city” [4]; on the contrary, farbigestadt devotees appreciated figure 1 p. bottoni, cromatismi architettonici, 1927. above: street 2 with ascending brightness; street 2 with descending brightness. below: street 1 at the vesper; street 3. archivio piero bottoni, dastu, politecnico di milano figura 1 p. bottoni, cromatismi architettonici, 1927. in alto: strada 2 a luminosità ascendente e discendente; in basso: strada 1 al vespro, strada 3. archivio piero bottoni, dastu, politecnico di milano. 2. gradazioni cromatiche nell’architettura europea il dibattito sul colore nell’architettura europea degli anni venti si svolse soprattutto oltralpe, in ambienti culturalmente distanti fra loro ma parimenti animati dal desiderio avanguardistico di rivoluzionare il linguaggio e l’aspetto delle città. se la policromia urbana di bottoni per le corbusier non poteva essere dissociata da nuovi criteri di composizione architettonica, riducendosi altrimenti ad un semplice correttivo, un rimedio contro “la casualità che presiede alla costruzione della città attuale” [4], 10 cultura e scienza del colore color culture and science | 06 | 2016 | 0722 colonnese f. issn 2384-9568 doi:10.23738/ccsj.i62016.01 it as a scientific reference that deserved to be translated and published [5] especially for its vernacular potential [6]. the idea of the “colorful city” was derived from the transparent city dreamed of by paul sheerbart and inspired by the experience of the glass pavilion bruno taut had designed for the cologne exhibition of 1914. its “dome, in rhombic spaces between the reinforced concrete ribs, was illuminated by luxfer glass prisms arranged so as to create a sort of nuanced sunrise. the colors in fact began ‘with the night blue in the lower zone, passed through the green moss, rose to golden yellow, and ended in the upper space with a radiant yellow light’” [7]. also by virtue of such an experience, mythologized by the demolition of the pavilion and perpetuated in the writings of the gläserne kette in the pages of frühlicht, the color gradation acquired a symbolic value, which could be applied from the scale of the room to that of a city. in nirwana residential building in the hague (1917-1928), architects j. duiker and j.g. wiebenga [8] proposed an elaborate color solution in the living room opened on the long ribbon angular window through a gradation of colors which increases brightness and warmness from floor to ceiling (figure 2). bruno taut experienced instead the color as spiritual figure 2 j. duiker and j.g. wiebenga, nirwâna housing living room, the hague, 1917-1928 figura 2 j. duiker e j.g. wiebenga, soggiorno delle residenze nirwâna a l’aia, 1917-1928 per i fautori della farbigestadt essa costituì un riferimento scientifico che meritava di essere tradotto e pubblicato [5] soprattutto per le sue potenzialità vernacolari [6]. l’idea della “città colorata” derivava dalla città trasparente sognata da paul sheerbart e ispirata dall’esperienza del padiglione di vetro progettato da bruno taut per l’esposizione di colonia del 1914. la sua “cupola, negli spazi rombici compresi tra le nervature di cemento armato, era illuminata da prismi di vetro luxfer disposti in modo da creare una sorta di alba trascolorante. i colori infatti iniziavano ‘con il blu notte della parte inferiore, passavano per il verde muschio salivano al giallo oro, e all’apice dello spazio terminavano con un radioso giallo chiaro’” [7]. in virtù anche di una tale esperienza, mitizzata dalla stessa demolizione del padiglione e perpetuata negli scritti della gläserne kette sulle pagine di frühlicht, il tema della gradazione cromatica acquistò un valore simbolico ancor prima che percettivo, che poteva applicarsi dalla scala della stanza a quella della città. gli architetti j. duiker e j.g. wiebenga, che nell’edificio residenziale nirwâna a l’aia (1917-1928) [8], proposero una elaborata soluzione cromatica per il soggiorno spalancato sulla lunga finestra a nastro angolare, mediante una gradazione di colori che aumenta di luminosità e calore 11 cultura e scienza del colore color culture and science | 06 | 2016 | 0722 chromatic gradation as a symbolic and spatial device in the european context: piero bottoni’s cromatismi architettonici issn 2384-9568 and social catalyst in the great urban laboratory of magdeburg, to transcend the austere forms of the wilhelmine architecture into “a joyful architecture, able to instill a sense of optimism and harmony in daily life” [9]. taut assumed the color theme for a more central role, and even independent from the formal one, since “it does not necessarily run parallel to that of the form but, in contrast, it may either interbreed with this, or dissociate to create a dissonance in the reunification with the other theme” [10]. the same assumptions can be found in the use of gradations in the revolutionary russia, where the colors took on a subversive power and precise political significance, useful to announce the advent of a new civilization. when the cubist artist natan altman intervened pictorially on the monumental facade of petrograd, with shades from yellow to red, kazimir malevich interpreted it in a political and evolutionary key: “the form of the international presents a chromatic palette. now we have three forms of the international, which are distinguished by the color intensity. the first is characterized by a yellow background, in which a red component creates ‘the orangeness’; in the second, this shade increases to become fully orange. the third should be completely red, as the form of the third international should aspire to eliminate the differences and its red will be the color of equality” [11] . in the land of the soviets, the gradation was designed not only to symbolize the social evolution but also to manipulate the perception of space. precise experiments in this direction were conducted in vkhutemas art school (higher art and technic institute). set up in moscow as part of the reforms promoted since 1918 by the people’s commissariat for education, it encouraged the exploration of space, rhythm, and color through an interdisciplinary approach, involving scientists, philosophers, artists, linguists, and architects to redefine the relationships artistic and intellectual production establishes with the reality. in the 1923 course guided by v. f. krinsij, a demonstration design for a soviet pavilion for silicone products adopted gray to red grades to mark the jagged exterior surfaces, enhancing its volumetric articulation (figure 4). conversely, in 1929 mausoleum for lenin, scusev applied color gradations to the upper pyramid to “fade” its revolutionary red in the atmosphere, and with figure 3 b. taut, housing in berlinweissensee, 1928-30 (photo by the author) figura 3 b. taut, residenze a berlinweissensee, 1928-30 (foto di f. colonnese). salendo verso il soffitto (figura 2). bruno taut sperimentò invece il colore come catalizzatore spirituale e sociale nel grande laboratorio urbano di magdeburgo, per trascendere le “seriose” forme dell’edilizia guglielmina in “una architettura gioiosa, capace di instillare nella vita quotidiana un senso di ottimismo e di armonia” [9]. taut ipotizzava per il tema cromatico un ruolo ancora più centrale e perfino autonomo rispetto a quello formale, visto “che non deve necessariamente correre parallelo a quello della forma ma, al contrario, può incrociarsi con questo, staccarsi, creare una dissonanza nella riunificazione con l’altro tema” [10]. gli stessi presupposti si ritrovano nell’utilizzo delle gradazioni cromatiche nella russia rivoluzionaria, dove i colori assunsero un potere eversivo e precisi significati politici, utili a mettere in scena l’avvento di una nuova civiltà. quando l’artista cubista natan altman intervenne pittoricamente sulle facciate monumentali dell’allora pietrogrado, con gradazioni dal giallo al rosso, kazimir malevich ne fornì una lettura in chiave politica ed evolutiva: “la forma dell’internazionale presenta una tavolozza cromatica. adesso abbiamo tre forme dell’internazionale, che si distinguono tra loro per l’intensità del colore. la prima è caratterizzata da un fondo giallo, nel quale 12 cultura e scienza del colore color culture and science | 06 | 2016 | 0722 colonnese f. issn 2384-9568 doi:10.23738/ccsj.i62016.01 it symbolically the last revolutionary echoes, like an application of leonardo’s “aerial perspective” (figure 5). vchutemas teachers such as el lissitzky, stepanova, vesnin, exter, malevich, and tatlin addressed the research “from painting to architecture, from the flat surface and color to the volume and space” [12 ]. kandinsky himself taught there before getting to the bauhaus in 1921, interlacing his research with that of his friend paul klee, who was in weimar from the previous year. kandisky’s vision figure 4 soviet pavilion for silicone products, course of prof. v.f.krinsij, ass. m. p korzev, s.v.glagolev, 1923 figura 4 padiglione sovietico dei prodotti siliconici, corso del prof. v.f.krinsij, ass. m. p korzev, s.v.glagolev, 1923 figure 5 a.v. šcusev, mausoleum for lenin in moscow, 1929 figura 5 a.v. šcusev, mausoleo per lenin a mosca, 1929 una componente rossa crea ‘l’arancionità’; nella seconda, questa tonalità aumenta fino a diventare pienamente arancione. la terza deve essere completamente rossa, poiché la forma della terza internazionale deve aspirare ad eliminare le differenze e il suo rosso sarà il colore dell’uguaglianza” [11]. nel paese dei soviet la gradazione cromatica era studiata non soltanto per simboleggiare l’evoluzione sociale ma anche per manipolare la percezione spaziale. precise sperimentazioni in tal senso furono condotte nella scuola superiore d’arte vchutemas (ateliers superiori tecnicoartistici), istituita a mosca nell’ambito delle riforme promosse dal 1918 dal commissariato 13 cultura e scienza del colore color culture and science | 06 | 2016 | 0722 chromatic gradation as a symbolic and spatial device in the european context: piero bottoni’s cromatismi architettonici issn 2384-9568 of the spiritual life in the form of “a large acute triangle divided into unequal sections, which narrow upwards” [13] can be found also in klee’s painting schemes [14] and indicates their common interest for color gradations. in the twenties, the swiss artist tested them to achieve a synthesis between their symbolic value of evolution and change and the purely perception of movement and variation in depth. he applied squared and striped color gradations to both recognizable figures and ambiguous abstract shapes open to figuration [15], often inspired by urban visions [16]. 3. “cromatismi architettonici” while twenties european architects mostly attributed symbolic values to color gradation, piero bottoni was rather interested in its perceptual potential to rearrange and transform the increasingly kinematical vision of existing urban fronts. his six studies in pencil and watercolor on 24,8x18,0cm vertical sheets [17] are today kept in the archivio piero bottoni in milan and have been already widely studied [18]. they show four different urban pieces that are also four different visions of the idea of city: the city on the sea (street 4, s4), with a large crescent waterfront; the “picturesque city” (street 2, s2), with wavy edges that define a medieval corso; the “modern city” (street 1, s1), with the straight avenue that opens into a square. the last watercolor (street 3, s3) abandons the urban scale and seems to focus on the architectural one, showing the two buildings coupled along a road. a part the “waterfront” – probably the most distant from bottoni’s background – which is artificially “seen” from an observer as high as the fifth floor, the other perspective views have the points of view of a man walking in the middle of road, probably to show both building fronts. the presence of openings both on the two fronts of the “picturesque city” street (s2) and on the frontal buildings (s3), confirms that each color band is one floor tall and identifies the internal apartments or offices. the represented urban spaces do not seem to follow an overall project. the absence of axes of symmetry, volumetric hierarchies or simply a continuous crowning –which bottoni instead refers to in his text – suggests they are “pictures” from an existing city. most of the buildings, tall from 4 to 8 floors, are simple scenes that are beyond any architectural characterization. nonetheless, bottoni could not help but suggesting some special solutions, such as the portholes on top of a tower in s3, while in s2 he designed large openings at the first floor of a building and a gradual retreating of the popolare dell’istruzione allo scopo di favorire l’esplorazione di spazio, ritmo e colore attraverso un approccio interdisciplinare, che coinvolgeva scienziati, filosofi, artisti, linguisti e architetti per ridefinire le relazioni che la produzione artistica e intellettuale instaura con la realtà. in un disegno dimostrativo del 1923 nel corso guidato dal v.f.krinsij per un padiglione sovietico dei prodotti siliconici, fasce cromatiche dal grigio al rosso scandiscono le superfici scalettate dell’involucro, contribuendo ad accentuare l’apparenza della sua articolazione volumetrica (fig. 4). viceversa, nel mausoleo per lenin di a.v. šcusev del 1929, la gradazione cromatica dei gradoni della sovrastante piramide sembra una applicazione della “prospettiva aerea” di leonardo, utile a “sbiadire” il rosso rivoluzionario nell’atmosfera e con esso simbolicamente gli ultimi echi rivoluzionari (figura 5). nel vchutemas, insegnanti come el lissitzky, stepanova, vesnin, exter, malevich e tatlin orientarono le ricerche “dalla pittura verso l’architettura, dalla superficie piana e dal colore verso il volume e lo spazio” [12]. lo stesso kandinsky vi insegnò prima di giungere al bauhaus nel 1921, intrecciando così le sue ricerche a quelle dell’amico paul klee, che si trovava a weimar dall’anno precedente. la visione della vita spirituale in forma di “un grande triangolo acuto diviso in sezioni diseguali, che si restringono verso l’alto” [13], espressa da kandinsky già nel 1912, si ritrova anche negli schemi pittorici di klee [14]. lo svizzero negli anni venti sembra sperimentare le gradazioni cromatiche per cercare una sintesi tra il loro valore simbolico di evoluzione e cambiamento e quello puramente percettivo di movimento e variazione di profondità. non è affatto trascurabile che molti dei suoi acquarelli, che usano gradazioni cromatiche in fasce e riquadri per la loro capacità di scomporre e qualificare la superficie pittorica sia in geometrie aperte alla significazione sia in figure ambigue e riconoscibili [15], appaiono ispirati proprio alla visione delle quinte urbane [16]. 3. “cromatismi architettonici” a dispetto della lettura prevalentemente simbolica che gli architetti europei attribuivano negli anni venti alle gradazioni cromatiche, piero bottoni era invece interessato alle sue potenzialità percettive di riordinare e trasformare la visione sempre più cinematica delle quinte urbane esistenti. i suoi sei studi a matita e acquarello di formato rettangolare 14 cultura e scienza del colore color culture and science | 06 | 2016 | 0722 colonnese f. issn 2384-9568 doi:10.23738/ccsj.i62016.01 upper floors. anyway, all of the views show only civil buildings: monuments and churches seem banished from the bottoni’s city. any sign of life is missing, too: no people, cars or street furniture. the shadows are the only evidence of a precise time in this atopic place. as specified by the captions, s1 is presented in two different times, at midday (s1m) and vespers (s1v) (but in reality some facades show slightly different colors). s2 is presented at noon but in two different color schemes. s3 is presented in the afternoon while the waterfront in s4 does not show a precise timing. bottoni’s use of colors requires further explanation. the hue (“color”) identifies the building while a single grade (a variation in “intensity” and “brightness”) identifies a horizontal portion as tall as a floor, marking it on all visible fronts. in general, the brightness seems to be quite constant along the vertical gradations; the more evident exception is the yellow face in s2, which, after the first two floors, seems to start from a darker tone. often the field that ends the gradation toward the dark appears abruptly saturated, breaking away from the constant step of the chromatic scale. in some cases, the hues that alternate along the street fronts are chosen to accentuate the mutual contrast, in other cases to attenuate it. an example of the former case is in s2, where some of facades on left show a combination of complementary colors like aquamarine green and red; an example of the latter case is in s3, dominated by a combination of blue and green. the two versions of s1 show some interesting cases of chromatic inversion: in particular, buildings with two different blue hues are translated into complementary gradation between yellow and green. 4. a spatial interpretation of cromatismi the city bottoni illustrated in his six watercolors is the city of the past and the present, in which the voids of streets and squares still form the core of the urban structure, just before modernistic urban planners shift the design focus on the blocks. the very concept of a color plan for urban design can only come from the raumkunst concept of a city as a system of open spaces. this is related to the late xix century urban planning manuals, such as hermann maertens’ studies for der optische massstab, through which he had mathematically connected visual physiology and proportions of urban voids [19]. camillo sitte’s research had instead contributed not only to consider the blocks as volumes serving the experience of urban space, but also to condemn the abuse of bird-eye’s views and to revive the glory of the perspective view at human eye level verticale 24,8x18,0cm [17],conservati presso l’omonimo archivio a milano e già ampiamente studiati [18], mostrano quattro differenti brani urbani che sono anche quattro diverse concezioni o momenti della città: la città di mare (strada 4, s4), con un ampio crescent – oggi si direbbe waterfront – rivolto verso l’acqua; la città pittoresca (strada 2, s2), con i fronti ondulati che definiscono un corso di sapore medioevale o settecentesco; la città moderna (strada 1, s1), con il rettifilo che si allarga in una piazza. l’ultimo acquarello (strada 3, s3) abbandona la scala urbana e sembra concentrarsi su quella architettonica, mostrando frontalmente due edifici accoppiati lungo una strada. se escludiamo il waterfront – probabilmente il più distante dall’ambiente culturale di bottoni – che appare artificiosamente visto dall’alto, all’incirca alla quota del quinto piano, le altre prospettive seguono il punto di vista di un uomo che cammina nel bel mezzo della strada, probabilmente per mostrare al meglio entrambi i fronti edilizi. la presenza delle bucature, su due fronti della città pittoresca e su quella frontale, permette di stabilire che le fasce cromatiche corrispondono alla altezza di un piano, identificando quindi le porzioni corrispondenti agli appartamenti o agli uffici interni. gli spazi urbani rappresentati non sembrano seguire un progetto d’insieme. l’assenza di assi di simmetria, di gerarchie volumetriche o semplicemente di un coronamento continuo – a cui invece si riferisce bottoni nel testo – fanno pensare ad una città esistente. la gran parte degli edifici, alti dai 4 agli 8 piani, sono semplici quinte che sfuggono la caratterizzazione architettonica. ciò nonostante bottoni non resiste dal suggerire alcune soluzioni particolari, come gli oblò in cima ad una torre in s3, le bucature a scala maggiore al primo piano di un edificio, esili arretramenti dei fronti dal secondo piano in poi oppure il progressivo arretramento degli ultimi piani di un corpo di fabbrica in s2. tutte le viste mostrano esclusivamente edifici generici: monumenti e chiese sembrano bandite dalla città di bottoni. ugualmente è assente ogni segno di vita: niente abitanti, automobili o arredo urbano. l’unico elemento che stabilisce un tempo preciso di questo luogo atopico sono le ombre. s1 è presentata in due momenti diversi, al mezzogiorno (s1m) e al vespro (s1v), come specificamente indicato in didascalia (ma in realtà cambia anche la veste cromatica di alcune facciate). s2 è invece presentata sempre al meriggio ma in due vesti cromatiche diverse. s3 è rappresentata al pomeriggio mentre la palazzata a mare in s4 non ha una collocazione temporale precisa. l’uso che bottoni fa del colore richiede un approfondimento. la tonalità (“colore”) 15 cultura e scienza del colore color culture and science | 06 | 2016 | 0722 chromatic gradation as a symbolic and spatial device in the european context: piero bottoni’s cromatismi architettonici issn 2384-9568 in urban planning [20], as testified also by the cromatismi. bottoni did not pursue a form indifferent to the content, but a key to express it, a sort of chromatic interface between interior and exterior. to explain his cromatismi, he adopted terms such as intensity, pressure, resistant values, center of gravity, loads, etc. with the clear intention of leading the operation with scientific criteria, as he will do in his entire career. the choice to apply chromatic bands as tall as the internal space are has the consequence of highlighting the floors constituting each building, projecting the form of private spaces onto the public fronts and, indirectly, reverberating the human measure. the color gradation should produce an optical exaltation of the values of mass and volume, also through the expression of the quantity and quality of the loads supported by the structure. thus, the version with darker grades down would express “a sense of balance and rest” [21] due to the intrinsic identities “bright is light” and “dark is heavy”. however, there is a “plastic” interpretation, too. bottoni surely knew leonardo da vinci’s valuable observations on “aerial perspective” in epigraph [22]. the milanese architect could be supposed to promote – in a purely scenic and illusory terms – a different space interpretation of urban fronts. the gradations would favor the perception of a fading of the higher part of the buildings or a gradual shifting of the individual floors, up to configure ideally stepped urban fronts. this is a formal typology mainly introduced by antonio sant’elia’s la città nuova (1914) and adolf loos with his terrassenhäus and zigguratshaped buildings for hotels and civic halls. in the twenties, henri sauvage associated his name to numerous studies for an habitat hygenique through immeubles à gradins which could appear as a modern parisian ziggurat. in milan, both piero portaluppi, with the 1920 amarillo district for allabanuel, and giovanni muzio, with his 1921 stepped houses for artists [23], knew this typology and may have introduced it to bottoni. the stepped housing model inspired also other italian architects, such as innocenzo sabatini and mario ridolfi, both present in the same italian rational architecture exhibition where bottoni exhibited his watercolors 5. the cromatismi from watercolors to digital and reality much of the undeniable charm of bottoni’s cromatismi resides not only in the ordered vision and chromatic symphony of the city as well the poetic and vaguely disturbing atmospheres, but also in the technique: watercolor inevitably evokes the idea of manual labor, human footprint identifica l’edificio mentre la singola gradazione (“intensità”) ne identifica una porzione orizzontale alta quanto un piano, marcandolo su tutte le facce visibili. in generale le fasce cromatiche orizzontali presentano una gradazione costante e ininterrotta della luminosità verso l’alto o verso il basso. l’unica eccezione evidente è costituita dal fronte arretrato giallo di s2 che, dopo i primi due piani, riparte da un tono più scuro. spesso il campo che conclude la gradazione verso lo scuro appare bruscamente saturato, staccandosi dal passo costante della scala cromatica. in alcuni casi le tonalità che si alternano lungo la strada sono scelte per accentuare il contrasto reciproco, in altri casi per attenuarlo. al primo caso appartengono alcune facciate lungo il fronte stradale sinistro di s2, in cui bottoni dispone gradazioni di tinte complementari verde acquamarina e rosso; al secondo caso quelle in vista frontale di s3, blu e verdi. le due versioni di s1 presentano alcuni interessanti casi di inversione cromatica: in particolare gli edifici caratterizzati da due diverse tinte blu si traducono in gradazioni complementari invertite tra il giallo e il verde. all’esito finale dei sei acquarelli concorrono, infine, le didascalie che li accompagnano, nelle quali bottoni integra le informazioni visive – decisamente depauperate nella loro versione editoriale in bianco e nero – con l’indicazione del momento del giorno e dell’effetto complessivo. 4. l’interpretazione spaziale dei cromatismi la città che bottoni illustra nei sei acquarelli è la città del passato e del presente, in cui i vuoti di strade e piazze formano ancora il fulcro della struttura urbana, poco prima che gli urbanisti spostino l’accento sui pieni degli isolati. il concetto stesso di un piano urbano del colore non può che scaturire dal concetto di raumkunst e di città come sistema di spazi aperti. esso è cioè legato alla manualistica urbanistica di fine ottocento, come gli studi di hermann maertens sulla optische massstab, che avevano legato matematicamente fisiologia visiva e proporzioni dei vuoti urbani [19]. le ricerche di camillo sitte avevano invece contribuito non solo a considerare gli isolati alla stregua di volumi neutri al servizio dell’esperienza spaziale urbana, ma anche a rinverdire i fasti dello scorcio prospettico ad altezza d’uomo, per secoli trascurato in favore di totalizzanti viste a volo d’uccello [20], che si riflette nell’idea di bottoni di presentare gli effetti dei cromatismi mediante prospettive ad altezza d’uomo lungo diverse tipologie di spazi urbani. i cromatismi non costituiscono una maschera indifferente al contenuto ma una chiave per esprimerlo. le finestre rettangolari disegnano 16 cultura e scienza del colore color culture and science | 06 | 2016 | 0722 colonnese f. issn 2384-9568 doi:10.23738/ccsj.i62016.01 and a sense of art, playing, and nostalgia, too. to evaluate cromatismi with eyes detached from all this, the author has arranged a digital version of the six of them (figure 6). from a digital reproduction of each of them, the author has redrafted the wireframe structure of buildings with regard to the visible vanishing points (twodimension model). this stage has highlighted the existence of a strict perspective structure but at the same time, a certain irregularity in the size of plans and floors. from digital images of watercolors, three values of color have been sampled at the extremes and middle of each graduated sequence. they have been used to produce a vertical gradient from which the author has selected the color values for the individual tonal gradations that have been applied to the raster version of each figure 6 from left to right, above to below: stages from the process of digital reproduction of cromatismi; digital version of s3, afternoon; digital version of s2, midday; digital version of s1, vesper (elaboration by the author) figura 6 da sinistra a destra, dall’alto in basso: fasi del processo di riproduzione digitale; versione digitale di s3, pomeriggio; versione digitale di s2, meriggio; versione digitale di s1, vespro (elaborazione di f. colonnese). un reticolo regolare, secondo uno schema che si stava affermando come la più diffusa interpretazione dell’edificio per abitazioni da parte degli architetti razionalisti. la scelta di applicare fasce di colore pari alla altezza degli interpiani ha la conseguenza di evidenziare i piani di cui si compone ogni edificio e, di conseguenza, di proiettare in facciata la misura degli spazi domestici (e indirettamente del corpo umano). per spiegare i suoi cromatismi architettonici, l’architetto adotta termini come intensità, pressione, valori resistenti, baricentro, carichi, ecc. col chiaro intento di guidare l’operazione con criteri scientifici, come accadrà in tutta la sua carriera. la colorazione dovrebbe quindi produrre una esaltazione ottica dei valori di massa e volume, anche attraverso l’espressione della quantità e 17 cultura e scienza del colore color culture and science | 06 | 2016 | 0722 chromatic gradation as a symbolic and spatial device in the european context: piero bottoni’s cromatismi architettonici issn 2384-9568 of the cad two-dimensional model. this phase has revealed occasional intensity corrections adopted by bottoni to mark the contrast between adjacent bands. after importing the cad drafted views into adobe photoshop, the selected colors have been applied to the buildings. a single color for the sky and windows has been chosen for all the views, although in reality it varies slightly within the same drawing. black-filled layers with different opacity have simulated shadows and shades while a texture has been applied to simulate a generic plaster texture. this operation has resulted in converting the watercolor shades in coordinates according to the adobe rgb color space. the digital version of colors bottoni chose to illustrate his plan, which have been collected as a partial color figure 7 chromatic palette adopted in cromatismi architettonici; digital simulation of color plan application to buildings facades in via roma in milan (image by the author) figura 7 palette cromatica utilizzata nei cromatismi architettonici; applicazione digitale dei cromatismi ai fronti edilizi di via roma a milano (elaborazione di f. colonnese). della qualità dei carichi sopportati dalla struttura. così la versione con gradazioni più scure verso il basso esprimerebbe “un senso di equilibrio e di riposo” [21] in virtù delle intrinseche identità “chiaro è leggero” e “scuro è pesante”. rileggendo le preziose osservazioni di leonardo da vinci sulla prospettiva aerea in epigrafe, certamente note anche a bottoni [22], si potrebbe ipotizzare che l’architetto milanese cercasse anche di favorire – in una chiave prettamente scenografica e illusoria – una diversa lettura spaziale dei fronti urbani. le gradazioni cromatiche favoriscono infatti la percezione di una dissolvenza della parte alta degli edifici oppure di uno slittamento graduale dei singoli piani, andando a configurare idealmente dei fronti urbani a gradoni. è questo un modello insediativo introdotto dai disegni di 18 cultura e scienza del colore color culture and science | 06 | 2016 | 0722 colonnese f. issn 2384-9568 doi:10.23738/ccsj.i62016.01 abacus, offers a total visual control over the final effect. starting from this intermediate product, a part of bottoni’s color plan has been virtually tested in a photograph of an existing urban context such as via roma in milan, whose completion dates back to the years of cromatismi (figure 7). after desaturating the buildings elements in photoshop, the author has applied color gradations layers according to the more evident horizontal partitions of facades. this stage has evidenced some difficulties in the treatment. the modern building on the right, already articulated by regular horizontal bands, happens to “painlessly” accept the color gradations; the building on the left, with simple rectangular windows, “allows” it, too; the following building, featuring bugnato and baroque-style frames, instead “resists” to the treatment. at the same time, this experiments highlight the chromatic role of the secondary elements bottoni has censured in his drawings, such as vegetation, signs, furniture, vehicles, even the red porphyry cobbles. beyond the final visual effect this process has highlighted a number of unresolved issues, in part apparently neglected by bottoni, in part related to the current appearance of the city. the former group includes: • the color criteria to be used for facades that have a hierarchical structure antagonist to the horizontal bands, for example with giant orders or decorative themes overlapping it; • hesitations regarding the chromatic treatment of facades covered with marble, stone, brick and ceramics; • the chromatic role of trees, gardens and private vegetation in such a scenario; • public lighting criteria to be accorded or not with the color plan; • the perception of the colorful fronts on means of transportation, whose speed and visual field condition the perception of urban fronts. the latter group includes: • the doubts raised by the current presence of signs and billboards, which contributes to a prevailing effect of visual confusion; • the potential contribution of public and private street furniture, especially tents and umbrellas; • the conflictual relationship with urban pollution and the progressive blackening of the facades. the actual submission of the color plan for a antonio sant’elia (la città nuova, 1914) che negli anni venti era stato proposto da vari autori. henri sauvage legò il suo nome a numerosi studi per un habitat hygenique attraverso immeubles à gradins che potevano apparire come moderni ziggurat parigini. nell’ambiente milanese, sia giovanni muzio, con le case per artisti nel 1921 [23], che piero portaluppi conoscevano tale modello insediativo e potrebbero averlo introdotto a bottoni. al modello “gradonato” si ispiravano altri autori italiani, come innocenzo sabatini o mario ridolfi, entrambi presenti nella stessa esposizione italiana di architettura razionale di roma del 1928 nella quale bottoni espose nuovamente i propri acquarelli. 6. i cromatismi dall’acquerello al digitale e al reale gran parte dell’innegabile fascino dei disegni di bottoni risiede non solo nella visione ordinata e cromaticamente sinfonica della città e nelle atmosfere poetiche e vagamente inquietanti, ma anche nella tecnica utilizzata: l’acquarello inevitabilmente evoca l’idea del lavoro manuale, dell’impronta umana oltre che un certo senso di arte, di gioco e, oggi, anche di nostalgia. per valutare i cromatismi con occhi distaccati da tutto ciò, ne sono state redatte delle versioni digitali, frutto di un procedimento che è stato applicato ai sei studi (figura 6). a partire dalle riproduzioni digitali degli acquarelli, è stato effettuato il ridisegno della struttura lineare in ambiente cad con riferimento ai punti di fuga. questo ha evidenziato l’esistenza di una rigorosa struttura prospettica ma al tempo stesso, una certa irregolarità nelle dimensioni dei piani. dalle immagini digitali degli acquarelli, sono stati campionati due valori cromatici agli estremi di ogni sequenza graduata: a partire da essi, è stata prodotta una sfumatura verticale da cui sono stati estratti i valori cromatici relativi alle singole gradazioni cromatiche che sono stati applicati alla versione raster del ridisegno vettoriale. questa operazione ha invece rivelato le occasionali correzioni di intensità adottate da bottoni per rimarcare il contrasto tra fasce contigue. il colore del cielo e delle finestre è stato scelto unico per tutti gli elementi, anche se in realtà varia leggermente all’interno dello stesso disegno. ombre proprie e portate sono simulate mediante l’applicazione di velature di grigio. è stata infine applicata una texture per simulare l’effetto visivo dell’intonaco. tale operazione è servita a convertire le sfumature ad acquarello in dati cromatici digitali secondo le coordinate dello spazio-colore adobe, offrendo un controllo visivo complessivo sull’effetto finale. le tinte scelte da bottoni per illustrare il suo piano 19 cultura e scienza del colore color culture and science | 06 | 2016 | 0722 chromatic gradation as a symbolic and spatial device in the european context: piero bottoni’s cromatismi architettonici issn 2384-9568 symphonic effect would imply its more or less contemporary application street by street. this would involve not only the necessary financial and administrative procedures but also a reliable criterion [24] for the conversion from adobe chromatic coordinates after the simulation to the ral color coordinates, for example, which are commonly used for the paintings in the building industry (and were curiously introduced in 1927). moreover, the aged and heterogeneous surfaces of existing buildings are supposed to react to colors in many different ways; not to mention the difficulties to adopt massively a mobile scaffolding to be either moved along the sidewalks or hung from the top of the taller buildings. 6. conclusions around the twenties, some european architects were concerned with color gradations especially for their spiritual potential; others, as piero bottoni was, for their ability to influence the perception of depth and organically connote the urban spaces. le corbusier put emphasis on the “physical function” and “space-creating action” performed by bottoni’s cromatismi, however, hoping to see them used with intent “symphonic” with the other architectural components. yet, bottoni’s realism towards the urban context had made him aware of the difficulty of acting on land values and property in order to plan a radical evolution of the existing urban landscape the way the swiss master was proposing. he thought rather to the way of pragmatically encourage citizens to regain a playful expression of their civic sense, a cross between a futurism destabilizing provocation and a reassuring urban décor scheme. he designed the color plan to revitalize the perception of urban fronts by horizontal bands and to “retune” the cacophonous urban scenery. a symphonic and collective impression of the city could favor a significant upgrading of a community. it is plausible that citizens, by seeing first recognized their individuality in a harmonized collective context, would actively participate in the social organism in which they are living in. even in this utopian collectivism, bottoni was trying to fit into certain european proposals, in particular those related to the innovative housing districts. the process of historical background reconstruction, analysis and spatial interpretation, digital reproduction of watercolors and digital simulation of the application of color gradations on a compatible urban site is illustrative and perfectible (starting from the optical scanning criteria of the original watercolors, which any discourse on the supposed “faithfulness” of the model must be postponed to). this process, even more than the final visual product, has been sono state raccolte e ordinate in un parziale abaco cromatico. la possibilità di applicare la restituzione prospettica ha inoltre offerto l’eventualità di rileggere la vera forma dei luoghi urbani rappresentati. a partire da questo prodotto intermedio, il passo successivo è consistito nel testare virtualmente almeno una parte delle soluzioni cromatiche di bottoni su un contesto urbano esistente. nella fotografia di un tratto di via roma a milano, la cui edilizia risale agli anni degli acquarelli (figura 7), le tinte degli elementi edilizi sono state “desaturate” e sono stati applicati dei veli cromatici a luminosità crescente verso l’alto in ambiente photoshop. l’esecuzione di questo procedimento ha messo in evidenza una serie di questioni irrisolte, in parte apparentemente trascurate da bottoni, in parte legate all’aspetto attuale della città. al primo gruppo appartengono: • i criteri di colorazione da utilizzare per facciate che presentano una struttura gerarchica antagonista alle fasce orizzontali, per esempio con ordini giganti o sovrapposizioni di temi decorativi; • le perplessità legate al trattamento cromatico di facciate rivestite con marmi, pietre, mattoni e ceramiche; • il ruolo cromatico che in un tale scenario si troverebbe a svolgere la vegetazione pubblica e privata; • i criteri di illuminazione pubblica in funzione o meno del piano del colore; • la percezione dei fronti mediante i mezzi di trasporto, che per velocità e campo visivo disponibile ne condizionano la percezione. al secondo gruppo appartengono invece: • i dubbi sollevati dalla presenza attuale della segnaletica e dei cartelloni, che contribuisce ad un prevalente effetto di confusione visiva; • il potenziale contributo di arredi stradali pubblici e privati, in particolare di tende e ombrelloni; • il conflittuale rapporto con l’inquinamento stradale e il progressivo annerimento delle facciate. accade così che nel foto-ritocco di via roma, l’edificio a destra, già articolato da marcapiani regolari, accolga in maniera indolore lo schema di bottoni; l’edificio a sinistra, con finestre rettangolari semplici, lo consenta; mentre quello successivo caratterizzato da bugnato e cornici baroccheggianti, “resista” al trattamento. allo 20 cultura e scienza del colore color culture and science | 06 | 2016 | 0722 colonnese f. issn 2384-9568 doi:10.23738/ccsj.i62016.01 useful to place scientifically bottoni’s proposal in a real urban context in order to identify at least some of the possible outcomes and limits, beyond the fascination of his watercolors. the validity of young bottoni’s intuition is proved not only by the developments and applications he was able to give it over the years, particularly in the sesto san giovanni town hall (1961-71) [25] but also the importance of color planning from 1970s on. such an instrument is currently used both to safeguard the overview of small villages and historic centers and to revitalize the modernist suburbs, often in collaboration with artists and neighborhood associations. by virtue of their inherent directionality, today the color gradations are also used to facilitate the orientation in large buildings, such as james stirling’s temasek polytechnic or rafael moneo’s madrid airport. artistic applications, which are favored by films coloring glasses (olafur eliasson’s your rainbow panorama in aalborg) and color-adjustable lighting devices (peter struycken’s tunnel at the rotterdam netherlands architecture institute), are generally addressed to exploit their symbolic value. on the contrary, buildings designed with bottoni-like color horizontal bands, like the civic centre custoias by guilherme machado vaz or the westminster academy in london by allford hall monaghan, reawaken the curiosity to see one day, at least one fragment of cromatismi put in place. funding this research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. conflict of interest nothing has affected my objectivity or independence in the production of this work as well as in the perception by others of my objectivity and independence. neither i nor my immediate family member have any financial interest in the people, topics or companies involved by this article. neither i nor my immediate family member had a professional relationship with the people and companies cited in this article. neither i nor my immediate family members are involved in a legal dispute with the people and the companies cited in this article. bibliography [1] e. maccurdy (editor), the notebooks by leonardo da vinci, new york, george braziller, 1955, p. 880. [2] m. cennamo, materiali per l’analisi dell’architettura stesso tempo, emergono i colori di elementi secondari, come la vegetazione, i segnali, gli arredi, i veicoli, perfino il porfido rosso del pavé, ad arricchire il “quadro” complessivo. qualora poi si immagini la effettiva realizzazione dei cromatismi in chiave sinfonica, quindi più o meno contemporanea strada per strada, occorrerebbe prendere in considerazione non solo i procedimenti finanziari e amministrativi necessari ma soprattutto un affidabile criterio di conversione [24] delle coordinate cromatiche adobe ricavate dalla simulazione visiva in coordinate cromatiche ral, ad esempio, usate per le pitture in edilizia e introdotte curiosamente proprio nel 1927, senza trascurare le diverse possibili “reazioni” da parte degli intonaci sottostanti, di epoche e qualità diverse; per non parlare della eventuale impalcatura mobile da spostare di volta in volta lungo i marciapiedi. 6. conclusioni intorno agli anni venti, alcuni architetti europei si interessarono alle gradazioni cromatiche soprattutto per il loro significato spirituale; altri, come lo stesso bottoni, per la loro capacità di influenzare la percezione della profondità e del contesto urbano generale. le corbusier mise in risalto la “funzione fisica” e “creatrice dello spazio” svolta dai cromatismi di bottoni, augurandosi però di vederli utilizzati con intenti “sinfonici” rispetto alle altre componenti architettoniche. eppure, una certa realistica sensibilità verso il contesto urbano aveva reso bottoni consapevole della difficoltà di agire sui valori fondiari e sulle proprietà per poter pianificare una radicale evoluzione dello scenario urbano, sul modello delle proposte dello svizzero. pensò piuttosto al modo di incentivare pragmaticamente i cittadini a ritrovare una espressione ludica di senso civico, a metà tra una destabilizzante provocazione futurista e il rassicurante decoro urbano. costruì la sua proposta non solo per dinamizzare la percezione dei fronti urbani per fasce orizzontali, ma soprattutto per riaccordare musicalmente le cacofoniche voci dello scenario urbano verso una impressione sinfonica e collettiva della città, quasi che in questo modo si potesse compiere un significativo passo nella costruzione di una nuova comunità. era plausibile che ogni singolo cittadino, vedendo innanzitutto riconosciuta la propria individualità in un contesto collettivo armonizzato, volesse più volentieri riconoscersi e partecipare attivamente dell’organismo sociale in cui viveva. quindi anche in questa tensione utopica e collettivistica, bottoni cercava di allinearsi con certe proposte europee, in particolare a quelle legate ai nuovi quartieri modello. il processo di inquadramento storico, di analisi ed interpretazione spaziale, di riproduzione digitale 21 cultura e scienza del colore color culture and science | 06 | 2016 | 0722 chromatic gradation as a symbolic and spatial device in the european context: piero bottoni’s cromatismi architettonici issn 2384-9568 moderna. la prima esposizione italiana di architettura razionale, napoli, fiorentino editore, 1973, s.p., figg. 5-10. [3] p. bottoni, “cromatismi architettonici”, in architettura e arti decorative, anno vi, nn. 1-2, 1927, p. 80. [4] le corbusier, parigi, 15 gennaio 1928, in g. consonni, l. meneghetti, g. tonon (editors), piero bottoni. opera completa, milano, 1990, p. 429. [5] bottoni’s work was translated in french (“chromatisme architectural”, in das werk, a. xv, n. 7, 1928, pp. 219-221) and german (“farbengebung in der architektur”, in die farbige stadt, n. 11, 1928, pp. 65-70; “die farbenwirkung in der architektur”, in süddeutsche maler zeitung, a. xxvii, n. 12, 1928, pp. 191-192). [6] g. frediani, policromia architettonica. regola e illusione, roma, gangemi, 1995, pp. 49-50. [7] p. portoghesi, “editoriale,” in materia, n. 60, 2009, pp. 44-45. [8] m. casciato, w. de jonge, “johannes duiker e il costruire funzionalista”, in casabella, n. 562, 1989, p. 50. [9] portoghesi, op. cit., p. 45. [10] b. taut, “pitture in architettura”, in frülicht 19201922. gli anni dell’avanguardia architettonica in germania, roma, mazzotta, 1974, pp. 143-144. [11] malevic is quoted in a. vyazemtseva, “il colore della rivoluzione: cromatismo e avanguardie storiche nella russia sovietica”, in g. jean (editor), la conservazione delle policromie nell’architettura del xx secolo / conservation of colour in 20th century architecture, lugano, nardini, 2013, p. 90. [12] l. zadova, “un contributo alla storia del vchutemas”, in casabella, n. 435, 1978, p. 50. [13] w. kandinsky, lo spirituale nell’arte, milano, bompiani, 1995, p. 23. [14] p. klee, eros, 1923. [15] p. klee, fuge in rot, 1921; greetings, 1922. [16] p. klee, traum-stadt, 1921; drei hauser, 1922; vier türme, 1923. [17] cfr. consonni, meneghetti, tonon, op.cit., pp. 25-29, 149-150. [18] cfr. g. tonon, “piero bottoni: il valore costruttivo del colore”, in g. jean, op.cit, pp. 161-180. for an exhaustive bibliography on piero bottoni, see: http://www. archiviobottoni.polimi.it (accessed on may 28th, 2016). [19] f. colonnese, m. carpiceci, “hermann maertens e der optische maassstab. la fisiologia della visione al servizio della raumkunst”, in actes du deuxième congrès suisse en histoire de l’art, lausanne, 22 – 24 août 2013 (forthcoming). [20] d. wieczorek, camillo sitte e gli inizi dell’urbanistica moderna, milano, jaca book, 1994, pp. 179-180. [21] p. bottoni, op.cit., p. 80. [22] on bottoni’s knowledge of leonardo’s ideas, see: consonni, meneguetti, tonon, op.cit., p. 36. [23] f. irace, giovanni muzio 1893-1982. opere, milano, electa,1994, p. 27. degli acquarelli e di simulazione con foto-ritocco su un sito urbano compatibile è esemplificativo e perfezionabile, a partire dai criteri di scansione ottica degli acquarelli originali, da cui deriva ogni altro eventuale discorso sulla “presunta” fedeltà al modello. tale processo, ancor più del prodotto visivo finale, è stato utile a calare la proposta di bottoni in un contesto reale pressappoco coevo alla sua intuizione per individuarne almeno una parte degli esiti e dei possibili limiti. che l’intuizione giovanile di bottoni fosse valida lo dimostrano non solo gli sviluppi e le applicazioni che egli ne seppe dare nel corso degli anni, in particolare nel municipio di sesto san giovanni (1961-71) [25] ma anche l’importanza che dagli anni settanta hanno assunto i piani del colore, da una parte per salvaguardare la visione d’insieme di piccoli borghi e centri storici, dall’altra per rivitalizzare le periferie moderniste, spesso in collaborazione con artisti e comitati di quartiere. in virtù della loro intrinseca direzionalità, oggi le gradazioni cromatiche sono utilizzate anche per favorire l’orientamento negli edifici di grandi dimensioni, come nel politecnico di temasek di james stirling o nell’aeroporto di madrid di moneo, mentre nelle applicazioni artistiche favorite dalle pellicole per colorare i vetri (rainbow di o. eliasson ad alborg) e dai dispositivi di illuminazione cromaticamente regolabili (tunnel di p. struycken all’istituto di architettura di rotterdam) tornano soprattutto ad esprimere il loro valore simbolico. assai, più raro è trovare un edificio concepito per fasce cromatiche orizzontali alla bottoni, come il centro civico de custoias di guilherme machado vaz o la westminter academy a londra di allford hall monaghan, che riaccendono la curiosità di vedere un giorno, almeno un frammento dei cromatismi messo in opera. 22 cultura e scienza del colore color culture and science | 06 | 2016 | 0722 colonnese f. issn 2384-9568 doi:10.23738/ccsj.i62016.01 [24] to realize the difficulty of this “translation”, see: c. oleari (editor), misurare il colore, milano, hoepli editore, 1998. [25] m. rossi, m. pompeiana iarossi, g. mele, “piero bottoni’s colourful city: theory, design and building”, in m. rossi (editor), colour and colorimetry. multidisciplinary contributions, vol x b, santarcangelo, maggioli, 2014, pp. 264-275. cultura e scienza del colore color culture and science cultura e scienza del colore color culture and science | special issue on food color | 05 | 2016 31 issn 2384-9568 domestic horticultural centric lighting design 1daria casciani daria.casciani@polimi.it 1fulvio musante fulvio.musante@polimi.it 1maurizio rossi maurizio.rossi@polimi.it 1dipartimento di design, laboratorio luce politecnico di milano abstract coloured lighting is a vital factor for plant growth, inducing both photosynthesis, phototropism and photomorphogenesis. detailed experimental studies on the photobiology of plant have already shown the importance of creating proper lighting receipts for different species, growth and developmental stages in order to obtain a good plant productivity and nutritional quality formation. leds, nowadays, are a good tool for creating the proper lighting receipts composed by different narrow spectral power distribution combined for specific plants. small dimension, long operating lifetime, great efficiency, digitally controllable features and optically controllable performances are also useful aspects for plants’ lighting system development not only for laboratorial research experimentation, for aerospatial and industrial food production but also in other filed such as domestic applications. in this domain, the research aimed at defining requirements and features of a lighting fixture for food growing that could be prototyped in an easy and economical way. the requirements were derived firstly from a scientific literature review about agriculture and food science in order to define the preferred characteristics of lighting for food growing in terms of quantity, spectral power distribution, spatial distribution, direction, temporal distribution. more than this a a qualitative survey was performed in order to derive further product’ specifications in terms of end-users’ interests in the functionalities, dimensions, price and interface features of the system. finally, the solutions were further developed in two prototypes that meet the following requirements: mixing between the different channels, ability to create relations of flow between the channels, the overall dimensions. the prototypes were meant as design probes for evaluating the usability and the impact of the product before proceeding to the detailed design. keywords coloured lighting, spectral power distribution, led lighting, horticultural lighting citation: casciani d., musante f., rossi m. (2016) ‘domestic horticultural centric lighting design’, cultura e scienza del colore color culture and science journal, special issue on food and colour, 05, pp. 31-40, doi: 10.23738/ccsj.i52016.04 received 20 june 2015; revised 14 december 2015; accepted 15 december 2015 cultura e scienza del colore color culture and science | special issue on food color | 05 | 2016 | 31 40 32 casciani d. et al. issn 2384-9568 doi: 10.23738/ccsj.i52016.04 1. introduction lighting and particularly coloured lighting is a vital factor that contributes to plant growth inducing both photosynthesis, phototropism and photo-morphogenesis. detailed experimental studies on the photobiology of plants have already shown the importance of creating lighting receipts specific for different species’ growth and development in order to obtain a good plant productivity and nutritional quality formation. leds, nowadays, represent a good solution for creating the proper lighting receipts composed by different narrow wavelength specifically combined for every plant. small dimensions, long operating lifetime, great efficiency, digitally controllable features and optically controllable performances are also useful aspects for an horticultural – centric lighting not only for laboratorial research experimentations, for aerospatial and industrial food production but also for educational, medicinal and therapeutic scopes [1-2-3]. more than this, domestic food farming is currently an increasing trend derived by both the emergent interest in eating healthy, genuine, km-0 and origin controlled food combined with a raising necessity of nature reconciliation through sustainable behaviours and responsible choices [4]. in this regard, an leds lighting system for home farming can be a possible solution especially in domestic environment lacking natural lighting or good climatic conditions, with limited or absent natural spaces as gardens, terraces and balconies. 2. research aim the research scope is defining requirements and features of a lighting system for food growing in domestic environments, by investigating and proposing a practical and ready to make designed solution considering not only technological problems but also user oriented issues. if the hypothesis is that leds are creating the opportunity for an energy efficient, reliable and qualitative superior system for domestic gardening, this papers would like to contribute with a series of guidelines and a designed proposal for the realization of an easy, economic, efficient, functional prototype that could be used for experimental research scopes. for reference, i compare the typical colors of the sweets packages in the us and japan in munsell notations and rgb variables (figure 9 and tables 1-3). 3. research methodology the requirements of the proposed domestic horticultural – centric lighting system were derived firstly from a scientific literature review about agriculture and food science in order to define the preferred characteristics of lighting for food growing in terms of quantity, spectral power distribution, spatial distribution, temporal distribution and direction. a quantitative qualitative survey was performed in order to derive further lighting system specifications in terms of end-users’ interests and attitudes in using an leds based system for domestic cultivation. more than this, the aim was to gather insights in terms of desired features to better define a domestic horticultural-centric leds based lighting system. 4. lighting requirements for plants according to the literature review, plants require light throughout their whole life-span from germination to flowering and seed production. quality, quantity and duration are the most relevant parameters of growing light influencing in different way the plant performance [6]: • light quantity (irradiance) is the main parameter which affects photosynthesis, a photochemical reaction within the chloroplasts of plant cells in which light energy is used to convert atmospheric co2 into carbohydrate; • light quality (spd spectral power distribution) of the radiation: this aspect regards which portion of the light emission is in the blue, green, red or other visible or invisible wavelength regions. these can be defined as “primary colours” and their mixture defines different spd (lighting receipts) specific for each plant. for photosynthesis, plants have the maximum response for red and blue light. light spectral distribution also has an effect on plant shape, development and flowering (photomorphogenesis). • light duration (photoperiod) is related to the developmental responses of plants to the relative lengths of light and dark periods and mainly affects flowering. plants are very selective in absorbing the proper wavelength according to their requirements. the most important part of electromagnetic spectrum is called par (photosynthetically active radiation) which spread from 400 to 700 nm. the fundamental problem to solve in the leds lighting engine design is to model different spd (it means to identify the proper number and the driving current of the “primary coloured leds”) to optimize the plant growth in an efficient way: the cultura e scienza del colore color culture and science | special issue on food color | 05 | 2016 | 31 40 33domestic horticultural centric lighting design issn 2384-9568 main idea is that a controlled and engineered spd would be much more beneficial for the plants rather than white light because it would allow to better control the flowering time, the high photosynthetic efficiency, the low heat stress in a more efficient and performance oriented way. the visible spectrum can be subdivided in several bands and each of them has a defined role in plant’s growing and photosynthesis process [7]: • 380–400 nm (ultraviolet a/visible light): the process of light absorption by plant pigments (chlorophylls and carotenoids) begins; • 400–520 nm (visible light: violet, blue and green bands): peak absorption by chlorophylls occurs in this range and has a strong influence on vegetative growth and photosynthesis; • 520–610 nm (visible light: green, yellow and orange bands): this range is less absorbed by the plant pigments and has less influence on vegetative growth and photosynthesis [8]; • 610–720 nm (visible light: red bands): a large amount of absorption occurs at this range, strongly affecting the vegetative growth, photosynthesis, flowering and budding; • 720–1000 nm (far-red/infrared): germination and flowering is influenced by this range but little absorption occurs at this band. the selection of the “primary colours” (in first approximation, good candidates are red, green-yellow, blue-violet) is important to photosynthesis. in addition to this, it is also important to consider the relative proportion or “red:blue” “red:green:blue” ratios. many studies [5] investigate the best mix of primary light sources to match them with the peaks of the absorbance curve of the plants [an example is reported in figure 2]. figure 1 absorption spectrum of chlorophyll and other photosynthetic pigments. adapted from margherita giacomozzi thesis “cibele, light for food” figure 2 comparison between the spd of three different leds and the absorbance spectra for the spinach plant. adapted from margherita giacomozzi thesis “cibele, light for food” cultura e scienza del colore color culture and science | special issue on food color | 05 | 2016 | 31 40 34 casciani d. et al. issn 2384-9568 doi: 10.23738/ccsj.i52016.04 5. users’ requirements for domestic horticultural centric lighting 5.1. participants for this study, 63 respondents (38.3% male 61,7% female) took part in the survey. the age of participants can be divided in two categories: 24-34 years old (68,3%), 35-47 years old, (31.6%). half of the participant was living in north italy (50%) and the other half was spread in europe (the netherlands 8.3%, uk 5.0%, spain 3.3%, austria 1,7%, belgium 1.7%, germany 1.7%, switzerland 1,7%,), east and far east (china 16.7%, turkey 3.3%, south korea 3.3%) and usa (3.3%). the survey was directed to people interested in the growing farming at home topic: the majority of the participants were architects, designers and engineers (34%) followed by educators, teachers and professors (17%), researcher (10%), psychologists and sociologists (7%). 5.2. users’ attitudes toward domestic horticultural-centric lighting from the survey, a strong majority of the participants (71.5% rating equal or greater than 6) affirmed that they were inclined in eating genuine food intending self-grown, km-0, pesticide-free (ave. 7.3; std. dev. 2.8 on a 0 10 scale). in addition to this, the 65.6% were positively in favour and willing to cultivate fruits or vegetables in their home with an indoor growing system (ave. 6.2; std.dev. 2.5 on a 0 10 scale). despite of this, the 52.5% were not particularly skilled in gardening and cultivating (ave. 4.3; std.dev. 2.7 on a 0 10 scale). this preliminary results shows some insights about the latent need of providing systems for gardening and food growing that help and support users with on-time information and feedback for better farming outcomes. the 48,2% were interested in using an leds based system for cultivating indoor (ave. 5.8; std.dev. 2.6 on a 0 10 scale), primarily because of the lack of spaces such as garden and balconies (41.3%), and consequently because of poor natural lighting and bad weather conditions in winter. in addition to this, people were interested in using an leds based lighting system for ensuring the growth of food for their own consumption (39,7%), also appreciating the opportunity of cultivating (and eating) some species off season (33.3%) and considering the interesting possibility of experimenting and learning (25.4%). other consideration regarded the educative and therapeutic purpose of horticulture at home (36.5%) that helps in stimulating children, adults and elderly people in their physical (exercise, sensory, stress release) psychological (accomplishment, confidence, biophilia hypothesis, connection with nature), intellectual (observation, experimenting, creativity, curiosity) and social skills (community, sharing). finally, leds were recognized as a more efficient technology for indoor growing compared to traditional lighting systems not only in terms of lower energy consumption but also in terms of the lighting quality provided that responds more precisely to plants’ needs, thus defining a more productive growing system. 6. requirements for an leds lighting system for domestic food growing from the scientific literature review and the survey, some requirements for a domestic horticultural-centric leds lighting system were defined. in particular, the research investigated features like dimensions, location and integration of the system in the domestic environment. in addition to this, the typologies of cultivation were explored and related to the proper lighting in terms of quantity, quality and duration for producing a congruous amount of species (not intensive industrial production), with particular interest in the efficiency of the led based lighting system combined with good flavours, aromas and nutrients of the food. the exploration focused also on the homely feeling figure 3 participants’ distribution in the world cultura e scienza del colore color culture and science | special issue on food color | 05 | 2016 | 31 40 35domestic horticultural centric lighting design issn 2384-9568 of the system considering the aesthetics, pleasantness, interest and domestic suitability. considering the not professional users, the investigation focused also on the perceived functionality and the overall simplicity of the system (installation, use, cleaning/maintenance, control and management). [9] 6.1 domestic integration: dimension and location preference the space required, considered available and useful for a domestic farming system was preferentially (49.1%) a thin, vertical volume (approx. 0.3 x 0.3 x 1.6 m) and a cubic compact volume (31.6%) (approx. 0.8 x 0.8 x 0.8 m) (figure 4). this dimensions shows both to have an appropriate capacity for cultivating a proper amount of food and to be also compatible and harmonious with the other domestic furniture, fitting the system into the limited domestic space available. in relation to this, in condense highrise apartment buildings the preferred room and location where to place the system were on the kitchen countertop (45%) or the pavement in any other available space of the house (38.3%), especially in the living and dining room. in other situations, such as villas and wider spaces, people suggested the use of a specific room such as a winter garden (20%), an old annex of the house or the basement / garage. 6.2 typology of cultivation and lighting needs from the survey the most interesting cultivation were: • vegetables (73.3%) (spinach, swiss chard, artichoke, zucchini, cabbage, eggplant, lettuce, tomatoes, cauliflower, fennel, celery, cardi, dandelion, broccoli head, endive, peppers, cucumbers, chicory, broccoli, turnip, pumpkin, leek); • spices and aromatic / medicinal plants (61.7%) (cumin, marjoram, thyme, chives, oregano, basil, mint, parsley, rosemary, sage) • small-medium fruit plants (51.7%) (strawberries, blueberries, raspberries, blackberries, currants). considering this list of desiderata, the lighting needs were derived from the scientific literature review and the lighting receipts (lighting quantity, quality and duration) were identified in order to be suitable and adaptable to the majority of plants by mixing the wavelength in an appropriate way and trying to limit the amount of different leds channels (primary colours) in order to reduce the overall costs. in table 1, a summary of the typology of cultivation and related lighting receipts was provided with examples. figure 4 domestic integration: dimensions preference figure 5 domestic integration: location preference cultura e scienza del colore color culture and science | special issue on food color | 05 | 2016 | 31 40 36 casciani d. et al. issn 2384-9568 doi: 10.23738/ccsj.i52016.04 in comparison to the lighting receipts found in the literature review as reference (refer to table 1), the authors selected one value of the peak position for each spectral band in order to develop the experimental lighting prototype characterized by extreme simplicity and reduced costs, adaptable to the domestic environment (avoiding dangerous uv or nir table 1 typology of cultivation and related lighting receipts (quality, quantity, duration) cultura e scienza del colore color culture and science | special issue on food color | 05 | 2016 | 31 40 37domestic horticultural centric lighting design issn 2384-9568 spectral emissions), flexible to be used to grow different species (table 2). in addition to this, particular care was given to the lighting uniformity which is stated as an important feature both for instantaneous and photoperiod lighting by the “lighting systems for agricultural” standard published by asabe (american society of agricultural and biological engineers). [10] 6.3 functionality + simplicity + domesticity people were confronted with three proposed solutions and some guidelines and insights were derived [16]. in particular, the main desired features were: • simplicity: in terms of use, installation, cleaning/maintenance • domesticity: compatibility with the domestic environment in terms of dimensions and location; • aesthetics: pleasantness and interest • functionality: in terms of effectiveness in food production • intelligence of the solution: in terms of flexibility, modularity and upgradability • control and management: simplicity in use and maintenance; flexibility in terms of information provided, adaptability to different cultivation; self-explanatory and helpful in providing knowledge. the comparison and assessment made by the participants conduced to a reasoned selection of two different solutions that are specific for two different user targets, for two different kind of domestic cultivation and also show different features. 7. leds based domestic horticultural – centric lighting proposal the solutions were further developed in two prototypes that meet the following requirements: • mixing between the different channels; • ability to create relations of flow between the channels; • the overall dimensions; the prototypes work as design probe useful for evaluating the usability and the impact of the product before proceeding to the detailed design. 7.1 domestic horticultural lampshade this solution [figure 6] hides the intelligence and the lighting performance into a designed lighting fixture which is both decorative and functional: it can be used for experimenting a small scale cultivation and for helping not so “green-fingered” users in taking care of their plants (especially in winter time). more than this, when the user is not interested in using it for cultivation, it can be reversed in a normal lighting fixture or it can create particular lighting atmospheres in the domestic environment. this solution is suitable for “naïve” cultivators and amateurs. the prototype achieves two different functions: light for plants growing and light for illumination of the environments. for this reason the device uses both a rgb led strip and a strip with warm white leds (3000k). it allows to adjust its height in order to better adapt to different plants and also to different levels of growth in an efficient way (figure 7). it is composed by the following part: • rgb led strip with 26 light diodes in smd (surface-mount device) package; • warm white with whit 48 light diodes in smd package; • reflector in high diffusive material (mcpet – microcellular pet) composed by a mixing chamber for blending the different colours and a central diffuser that scatter the light emitted directly from the led source; • plastic box with a round shape that includes all the other optical part and light source; • a plastic transparent diffuser with a high coefficient of transmission; • a constant voltage led driver: the current intensity is set by a resistor on pcb (printed circuit board) and the different ratios between the channels is achieved by pwm (pulse-width modulation) technique. 7.2 domestic horticultural cabinet this solution [figure 8] integrates the intelligence and lighting performances in a lighting engine designed to hack and re-adapt a cabinet system that can be placed in storage rooms hidden from the domestic environment or in a dining / table 2 primary led colour for horticulture light source cultura e scienza del colore color culture and science | special issue on food color | 05 | 2016 | 31 40 38 casciani d. et al. issn 2384-9568 doi: 10.23738/ccsj.i52016.04 living room integrated with other functions. it is a modular, upgradable, flexible solution, suitable for cultivating different species and farming a reasonable amount of food. the prototype is composed by the following part: • rgb led strip with 8 light diode in smd package; • reflector in high diffusive material (mcpet); • plastic box with a rectangular shape that includes all the other optical part and the light source; • a plastic transparent diffuser with a high coefficient of transmission; • a constant voltage led driver: the current intensity is set by a resistor on pcb and the different ratios between the channels is achieved by pwm technique. as shown in the figure 9, the prototype has been realized in a single module. the lighting appearance depends of the different lighting receipts realized by setting the different ratios between the blue and red channel as described figure 6 the domestic horticultural lampshade: a double functional horticultural / decorative lighting system figure 7 – the flexible lighting engine prototype of the domestic horticultural lampshade in table 1. 8. conclusions this paper focused on setting the requirements, envisioning some insights, proposing some guidelines and defining leds prototypes of domestic horticultural-centric lighting design based both on the scientific review and on users’ feedbacks, assessment and elicited observations. the released final prototype has been designed and built to be tested in a real environment. the survey was conducted on a reduced amount of subjects, but it can be hypothesized that the results can foreshadow emerging needs that in the future will be of interest to the broad masses of users. cultura e scienza del colore color culture and science | special issue on food color | 05 | 2016 | 31 40 39domestic horticultural centric lighting design issn 2384-9568 figure 8 the domestic horticultural cabinet: modular scalable furniture hacked with an horticultural lighting engine figure 9 the modular lighting engine prototype of the domestic horticultural cabinet bibliography [1] olle m. and virsule a. (2013) the effects of light emitting diode lighting on greenhouse plant growth and quality in agricultural and food science 22: 223-234 [2] liu w (2012) light environmental management for artificial protected horticulture. agrotechnol 1:101. http:// dx.doi.org/10.4172/2168-9881.1000101 [3] nelson ja, bugbee b (2014) economic analysis of greenhouse lighting: light emitting diodes vs. high intensity discharge fixtures. plos one 9(6):e99010. doi:10.1371/journal.pone.0099010 [4] merlo v. (2006), voglia di campagna. neoruralismo e città. città aperta isbn-10: 8881372401 [5] olle m. and viršile a. (2013), the effects of lightemitting diode lighting on greenhouse plant growth and quality, agricultural and food science 22:223-234 [6] nishio jl. why are higher plants green? evolution of the higher plant photosynthetic pigment complement. plant cell environ. 2000;23:539–548. 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(n.d.) contrasting effects of uv-a and uv-b on photosynthesis and photoprotection of beta-carotene in two dunaliella spp. plant and cell physiology, 43 (8) pp 877-884 [9] m.rossi, d. casciani, f. musante (2015) coloured leds lighting for food growing. in colour and colorimetry. multidisciplinary contributions. vol. xi b isbn 978-8899513-01-6 proceedings of the 11th conferenza del colore. p 109 119 [10] jianzhong j (2015) stakeholders make progress on led lighting horticulture standards, leds magazine, june 2015 – p. 38-41 [11] matthew a. mickens,raymond m. wheeler, a final report submitted in fulfillment of the requirements for the jpfp center-based research exp erience (cbre) 2012,”comparative study of lettuce and radish grown under red and blue light-emitting diodes (leds) and white fluorescent lamps” [12] gregory d gonis,”performance of salad-type plants grown under narrow-spectrum light emitting diodes controlled environment”. [13] l. b. prikupets and a. a. tikhomirov, “optimization of lamp spectrum for vegetable grown”, international lighting in controlled enviroments workshop, t.w.tibbitts (editor) 1994 nasa-cp-59-3309 [14] samuoliene g., brazaityte a., urbonaviciute a.,(2010) cultura e scienza del colore color culture and science | special issue on food color | 05 | 2016 | 31 40 40 casciani d. et al. issn 2384-9568 doi: 10.23738/ccsj.i52016.04 “the effect of red and blue light component on growth and development of frigo strawberries”, zemdirbysteagricolture,vol. 97, no. 2 (2010), p. 99-104 issnn 13923196 [15] folta k. m. and childers k. s. (2008) light as a growth regulator: controlling plant biology with narrowbandwidth solid-state lighting systems. hortscience vol. 43(7) december 2008 pp. 1957-1964 [16] m.rossi, d. casciani, f. musante (2015) coloured leds lighting for food growing. in colour and colorimetry. multidisciplinary contributions. vol. xi b isbn 978-8899513-01-6 proceedings of the 11th conferenza del colore. p 109 119 67 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110108 how the colours of objects and light affect human emotions, performance and health. the need for a holistic approach to design indoor environment. giuseppe barbato 1 , laura bellia 2 , alfonso morone 3 1 department of psychology, university “luigi vanvitelli”. giuseppe.barbato@unicampania.it 2 department of industrial engineering, university of naples federico ii. laura.bellia@unina.it 3 department of architecture, university of naples federico ii. alfonso.morone@unina.it corresponding author: alfonso morone (alfonso.morone@unina.it) abstract colours and lights have been shown to influence mood and performance, "cool colours" like blue and green are relaxing and peaceful to the eye, whereas "warm colours" such as red and yellow seem activating and arousing. cool light, rich in short wavelength radiations, has also a significant effect in terms of circadian rhythm synchronization by inducing melatonin suppression. for colours to be used in industrial objects, social and cultural factors also play a significant role. the choice of colours in indoor environments, for both objects and light, should thus be done considering all these aspects. however, these different approaches lead to different points of view and to hardly comparable results. also, the design process is unique and the final user is not able to distinguish between colour perception, visual and non visual effects of light as well as messages that can be expressed by means of colour patterns. it appears necessary to establish reciprocal interactions among the different disciplines involved in the choice of objects and light colours, and namely among researchers in medical science, psychology, lighting and industrial design, in order to assess an interdisciplinary methodology that can be applied to indoor design. keywords identity, quality, visual context, indoor environment, perception, properties, circadian cycle received 24 september 2018; revised 17 may 2019; accepted 03 june 2019 citation: barbato, g., bellia, l., & morone, a. (2019). how the colours of objects and light affect human emotions, performance and health. the need for a holistic approach to design indoor environment. color culture and science journal, 11(1), 67–73. https://doi.org/10.23738/ccsj.110108 mailto:laura.bellia@unina.it mailto:alfonso.morone@unina.it how the colours of objects and light affect human emotions, performance and health. the need for a holistic approach to desig n indoor environment. 68 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110108 1. introduction colours and lights have an influence on humans' mood and performance (bourgin and hubbard, 2016; ou et al. 2004). indeed, in an indoor environment, walls and furniture colours affect the perception of the space and induce different psychological states (yildirima et al. 2007). in the scientific literature several experiments have been carried out to study colour preferences and emotional effects, also looking at different contexts and application. despite the use of different methodologies and visual tasks, findings are generally in agreement in asserting that "cool colours" like blue and green are relaxing, calming and peaceful, whereas "warm colours" such as red and yellow result activating and arousing (al-ayash et al. 2016). all experimental research performed on the circadian effects of light demonstrate that cool light, rich in short wavelength radiations, has a greater effect in terms of melatonin suppression (brainard et al. 2001). blue enriched light, i.e. lights with a great amount of shortwavelength radiations and cct greater than 10000k have a positive effect both on seasonal affective disorder (bright light reduces sad symptoms) and on cognitive performances in educational and office environments, stimulating attention and alertness (thapan e al. 2001; viola et al. 2008). from the above considerations it seems that the choice of colours in indoor environments, either for objects and for lights, should be done considering both their physiological and psychological effects. actually, things are much more complicated because it should be also taken into account that, in the choice of colours for objects and specifically industrial objects, social and cultural factors play a big role. despite those different approaches lead to different points of view and to hardly comparable results, we must not forget that the design process is unique and that the final user, i.e. an observer in an indoor environment. is not able to distinguish between colour perception, visual and non visual effects of light as well as messages that can be expressed by colour patterns, whatever the application can be (office, shop, school, hospital, etc.). on the contrary, they globally perceive whether the lit environment is pleasant and suitable, for the specific activity to be performed, regardless of the specific strategy the designer could have adopted. given these premises, it appears necessary to establish reciprocal knowledge and interactions among the different disciplines involved in the choices for objects and light colours, and namely among researchers in medical science, psychology, lighting design and industrial design. the aim of this paper is to discuss these interactions, by comparing the different approaches, in order to find some common grounds and develop integrated research activities. 2. objects colours: identity and quality colour represents the first visible item of the identity of a product. it characterizes the quality and therefore it is the subject of a complex cultural assessment, which over the years has been substantially changed (pine, 1993). the approach to colour should also be framed within the more general definition of industrial product quality. for decades, the idea of product quality has been associated exclusively to performance aspects. over time the increase of the cultural dimension in all product activities and consumer patterns has shifted the focus towards more complex and less immediate aspects than those purely functional in defining the qualitative components of a product (carmagnola, 1991; garvin, 1988). a first phase of motivation in colour choice is related to the need for early serial industrialization. the role attributed to the choice of colours in the production in this period of history, can be synthesized by the famous phrase of one of the protagonists of mass production, the american industrialist henry ford. he summarized with the following sentence the need to limit colour choice and to adjust its production process which was characterized by a single assembly line: "any colour in the choices of a car is permissible, as long as it's black". it was precisely through this peremptory affirmation of henry ford, about the lack of choices other than black, that started the first theoretical formulations of those principles of standardization at the base of mass production. the monochrome trend in the early mass industrialization, the “only black” of “fordism”, launched a message of product longevity, opposed to the polychromy transience which expressed the rise, in the same period, of the fashion phenomenology. however, it is precisely around the expressive power of colour that the gradual overcoming of “fordism” occurred, replaced by a plurality of languages. attention to the chromatic expression has gradually focused towards the search for an interaction between the user and the product that has been a central point of the various theories of colour, starting from the one by johannes itten and the painter and his student josef albers who, in order to summarize this process, introduced the concept of "epidermis of materials" (albers, 1963). since the first half of the 20 th how the colours of objects and light affect human emotions, performance and health. the need for a holistic approach to design indoor environment. 69 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110108 century, just starting from itten's colour research within the bauhaus educational programmes, a specific attention to colour themes in industrial production has been confirmed. a very interesting field in which these transformations can be observed is that of the typewriter. at the beginning of the mechanization of writing, between the first and second decade of the last century, we find machines with some common features in all production systems: strong mechanical standardization and the exclusive use of the fired enameled black colour for the frame (giedion, 1948). when in the early 1930s many european engineering industries decided to launch the first portable typewriter for private users, the first tangible sign of this little revolution was just assigned to the colour. to the traditional and exclusive black of the first series, a wide variety in the choice of colours was added. in 1932, for example, olivetti launched its first laptop for home use, the mp1, it was built in seven colours: red, blue, light blue, brown, green, grey and ivory. the first customization in the industrial production season had started. the small mechanics began to enter homes through the lightness of colour, by adapting to the variability of domestic furniture. the first portable olivetti of the thirties and forties will be followed by nizzoli’s “letter 22”, which will be one of the italian design icons of the 1950s. nevertheless, it is thanks to the postrationalist revolution of the sixties that product hyperchromatization was used as a metaphor for the young revolution. in 1968, the “valentine” by ettore sottsass and perry king represents the most evident case of pop culture chromatic exacerbation. for the first time, an industrial object, just like any other item of clothing would do, adheres both to the worlds of production and communication (brusatin, 1983). this opens a road, which leads to present days, where the translucent white colour and the brushed aluminium of jonathan ive’s apple products finishing is the main iconic brand identity element and, more than any other, is the true image of modernity (castelli, 1999). it is due to this ideological character assumed by colour in relation to the product, it is through this subject that it is possible to recognize the border between the product and the brand in current industrial production. studying the different ways how an object, as well space, from a physical matter, becomes the privileged place of brand communication, one discovers that colours represent the matter that formalizes this step, and it can be also considered as the threshold point between the abstract and the real physical space. the chromatic experience allows us to understand the first transformation of goods, from necessary objects for basic needs to desired dream objects. around the mid19 th century in paris, with the “passages”, indoor malls were created. a busy social area with shops, cafés and theatres. here the skylight, covered with thin layers of glass filtering the natural light, emitted a bluish colour cast that surrounded people, goods and architectures, placing spaces and products in an immaterial and oneiric dimension (codeluppi, 2000). after this first example, colour, owing to its mnemonic strength, has always been, starting with the primary red coca cola label, and together with the logo, the main element of brand recognition. in addition, colour is one of the elements around which a brand name in a shop is characterized. 3. light and objects colours as far as interior objects and walls colours are concerned, architects and interior designers should take into account lighting, both for its spatial and spectral characteristics. nevertheless, human visual system is characterized by a good “colour constancy”, this is true especially for daylight whereas, in presence of electric light, sources spds can sometimes significantly affect colour perception. indeed, light stimuli that reach the eyes are a combination of sources spds and materials spectral reflectance and transmittance; however, this is not sufficient to predict how the colours are perceived and whether they appear pleasant and realistic. the visual context in which objects are observed and human visual system adaptation have a big influence in object perception. in the lighting design practice, the chromatic characteristic of light sources are synthesized by two main parameters: correlated colour temperature (cct) and colour rendering index (cri). before the diffusion of leds, these parameters were quite indicative and useful for lighting designers to determine their choices, but modern standards now call them into question. spectra rich in short wavelengths in the visible range are characterized by high ccts (cool light), whereas spectra rich in long wavelengths correspond to low ccts (warm light). daylight is characterized by different ccts, depending on the solar position on the sky vault, cloudiness, and if considering only the sky or the sun or both. d65 standard daylight illuminant cct is 6500 k, whereas north blue sky cct is between 10000k-20000k and, if considering sunset/sunrise light, very low cct values are attained, around 3000k. as typical indoor electric light sources are concerned, incandescent halogen lamps cct values range between 2700k 3000k, fluorescent lamps are available at different ccts, between 2700 k and 6500 k as well as led sources, which can reach even higher values (7500 k). moreover how the colours of objects and light affect human emotions, performance and health. the need for a holistic approach to design indoor environment. 70 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110108 white tuning led light sources currently available allow to change spds according to users' preferences or to change other conditions, such as light scenes, time of the day, illuminance levels, etc. in designing an indoor lighting system, besides luminaires dimensioning and photometric choices, cct is a topic of concern. (kruithof, 1941) established correlations between illuminances and preferred ccts, and more recently, (viénot et al. 2009) demonstrated that, with led sources characterized by very high cris, most results are in agreement with kruithof’s original findings, but with some exceptions, concluding that more researches are necessary. moreover, since the advent of leds, the colour rendering index (cri) has revealed some shortcomings and for this reason new indices were proposed as in (li et al. 2012; smet at al. 2019) and a cie technical committee (tc 190) was established in order to produce the technical report “cie 2017 colour fidelity index for accurate scientific use”. basing on some of the findings obtained by these researches, the ansi/ies tm-30-18 standard (ansi/ies, 2018) proposes a method for evaluating light source color rendition, quantifying both average properties (color fidelity, gamut area) and hue-specific properties (fidelity, chroma shift, hue shift) of a light source. this standard, characterized by an objective and statistical approach without considering subjective evaluation, has been currently adopted in the usa and in other countries. at the same time researches from all over the world proposed other indexes useful to describe the “colour quality” of a light source (teunissen, 2016; lin et al. 2016; smet et al. 2016; jost-boissard et al. 2015). from the above considerations it can be stressed that, when speaking of “colour of light”, many aspects are involved and that the final effect is done by the combination of light and spectral properties of materials. the question is: “given the great availability of spectra, what is the best light for a given environment?”. but at the same time: “what are the best colours for objects and walls in a given environment?”. these two questions cannot be formulated separately, probably a better question is “what is the best combination of light and objects colours?”. the possible answers are not easy, because if on one side cultural and social choices are performed, on the other material and lighting technologies offer new capabilities. even with an attempt of a brutal simplification, for example in the choice of “warm” and “cool” colours both for objects and for light, many contradictions arise: red colour, for example is often associated to danger and alerting, whereas blue-green colours are chosen in hospitals walls because inducing peacefulness and calmness feelings. however, considering also non visual effects of light, which will better examined in the following section, it has been proven that, under the same other conditions, cool light sources are more effective than warm ones in melatonin suppression (rea et al. 2010). furthermore (viola et al. 2008) demonstrated that exposure to blueenriched white light during daytime work hours improves subjective alertness, performance, and evening fatigue. physiology of vision, effects of light on health and psychological aspects are to be considered as well, and easy results are not so immediate. 4. visual and non visual effects of light stimuli visual and non visual effects of light occur by stimulating different parts of the eyebrain system. in the case of vision, light falling on objects activates a phototransduction process, photo-receptors in the retina transform the physical signal into an electrochemical one which then activates the neural-vision process. specific properties of objects also determine the characteristics of the light which activates the eye-brain system. the final product of vision is what is called “perception”, physical properties of the external world are “seen” as objects by the brain. perception is acquired using both intensity variation of the light and its spectral variation leading respectively information on luminance and chromatic characteristics (moutossis, 2016). sensitivity to luminance and chromatic characteristics are advantageous for an organism, allowing information helpful in a visually noisy environment; indeed primates have three different types of light-sensitive cone cells, instead of two as in other mammals, that allow a better colour discrimination. furthermore, colour vision gives what are probably the most important signals for the psychological characterization of the perceived object. colour gives information about vital signals, sexual signals for reproduction, as well as information on health and emotional states. the non visual signal is central for the synchronization with the external timing of light and dark, which organizes the life and behavior of the living species, and photosensitive retinal ganglion cells (iprgcs) that contain the photopigment (melanopsin) are mainly responsible for the information regarding light (graham and wong, 2016). these cells are able to incorporate light signals over an extended period of time resulting in an increase of sensitivity during prolonged light stimulation, iprgcs are most sensitive to wavelengths that are in the blue region (λ max = 482– 484 nm) of the light spectrum which is also close to the light spectrum (λ max = 459 nm) responsible for melatonin suppression. how the colours of objects and light affect human emotions, performance and health. the need for a holistic approach to design indoor environment. 71 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110108 current light environment however differs radically from the one animal species and our ancestors experienced during evolution. the most dramatic changes occurred at the end of the nineteenth century with the introduction of electric light that has produced an artificial prolongation of natural daylight and the suppression of the seasonal lighting cycle, with important changes in human behavior and physiology (wehr et al. 1993). furthermore, in recent years the “artificial light revolution” together with the progressive reduction of the natural light exposure due to energy saving building design, has produced a significant variation of the natural 24 h light/dark cycle leading to around-the-clock artificial lighting that differs markedly in spectrum, intensity and temporal patterns compared to natural lighting. daytime sunlight is necessary for circadian clock synchronization as well as for vitamin d synthesis, a regulator of several biological processes, and nighttime darkness is also necessary for melatonin synthesis, the hormone which contributes to regulating the physiological processes occurring within the so called biological night. thus the 24 h external day/night cycle synchronizes the suprachiasmatic nuclei that regulate the circadian oscillation of human activity and rest (smolensky et al. 2015). currently available light sources (leds) are often rich in short wavelengths in the visible spectrum (improperly called “blue light”) and even low intensity of such blue light is capable to attenuate or suppress melatonin synthesis producing a significant sleep disturbance. this light spectrum, on the other hand is capable of reducing sleepiness effects and thus can be used to alert subjects when this effect is necessary (lockley et al. 2006; phipps-nelson et al. 2009; sahim and figueiro, 2013). non visual effects of light can be analyzed by measuring or calculating spectral irradiances at the eye-level and, especially in indoor environments, they depend not only on light sources spds but also on spectral reflectance of walls and furniture: in other words they depend also on walls and furniture colours. as a general rule, in order to achieve very comfortable visual conditions, it's recommended to avoid that direct light from light sources strikes on observers' eyes, so often indirect light, as a result of multiple reflections, assumes a relevant role in affecting spectral irradiances at the eyes level (bellia et al. 2017). obviously both visual and non visual effects of light depend also on intensity besides spds. indeed, the choice of surfaces and furniture colours with different reflectance factors affect the amount of light reaching the eye. light colours for walls are to be preferred for most applications, in order to increase adaptation luminance and illuminances both for visual comfort and energy saving. 5. conclusions when we look at an object located in an environment, the colours of both these components should be considered, since the object transmits a message and the environment has a specified identity. the light stimuli at the eye are given by the radiations coming from the object and from its surroundings (context). in this phase, lighting (i.e. primary sources) takes up a relevant role as well as the spectral optical properties of the lit surfaces. given these stimuli, the human visual system performs an adaptation involving all eye components (pupil diameter, rods and cones pigmentation or depigmentation, lens thickness, etc.), then sensorial cells (rods, cones, iprgcs) transduce these stimuli into electric signals and neuro-transmitter cells send these signals, properly processed, to the brain cortex. through very complex mechanisms these signals are sent to different brain and body areas, for different purposes, like the regulation or activation of the circadian rhythm, or the perception of the object and its surroundings, also involving different cognitive activities. so, a physical stimulus (light) coming from the surrounding environment is processed by the eye-brain system in multiple ways in order to guarantee survival and for other secondary purposes. this can be the reason why light signals, received by different areas, could induce contrasting effects: a cool light could be “melatonin suppressing”, throughout iprgcs-scn pathway, but at the same time being perceived as relaxing throughout the eye-brain cognitive processes. this complexity is accentuated by personal experiences as well as by subjective cultural and social backgrounds. for these reasons, when approaching the theme of the choice of objects and light colours for indoor environments in order to obtain proper visual conditions, enhance human performances, regulate circadian rhythms, satisfy esthetical, cultural and social expectations, it is very difficult to find a solution that fulfill all the requirements and at the same time result satisfactory for most people. as for all complex problems, each of the factors that concur to a good environmental quality and to visual aspects should be addressed . indeed, these factors involve very different branches of knowledge, as medical science, psychology, interior design, lighting design, as well as the technology of materials and lighting. considering only some of these branches and neglecting the others could lead to great mistakes. one initial obstacle is that nomenclature and language for the different branches sometimes strongly how the colours of objects and light affect human emotions, performance and health. the need for a holistic approach to design indoor environment. 72 color culture and science journal vol. 11 (1) doi: 10.23738/ccsj.110108 differ, creating communication problems. on the other hand, many intersections can be detected and the same subject of study, and can be seen by different points of view that, altogether, can better explain some phenomena or harmonize apparent contrasts. it appears thus necessary a really “human focused” methodology which bonds knowledge from the different fields to produce an environment able to satisfy those several needs. an ideal indoor design should consider not only the daylight availability, the electric light and its possible manipulations to guarantee the adequate photometric parameters for the room's purposes, but also the window design, the interior colour of walls and furniture, and all these variables should be fine tuned to allow the comfort and wellness of the final client that is the human being. experimental procedures on colour/light manipulation that take into account the human factors should be further implemented to better understand effects of such physical entities on emotion and cognitive performances 6. conflict of interest declaration the authors disclose any actual or potential conflicts of interest including financial, personal or other relationship with other people or organizations within three years of beginning the submitted work that could inappropriately influence, or be perceived to influence, their work. 7. funding source declaration this research did not receive any specific grant from funding agencies in the public, commercial, or not-forprofit sector. 8. short biography of the author(s) giuseppe barbato • giuseppe barbato, m.d., ph.d., psychiatrist, is full time associate professor at the university of campania, luigi vanvitelli. he has been involved in research addressing the role of photoperiod in regulating human psychophysiological systems and on rem sleep regulation. his current research include analysis of the dopaminergic system and the effects of light on arousal and performance. laura bellia • laura bellia, msc, phd is full professor of lighting and building physics at the department of industrial engineering of the university of naples federico ii, italy. her research's topics and interests include lighting, daylighting, smart lighting systems and automatic controls, lighting quality, visual comfort, glare, non-visual effects of lighting as circadian effects, led sources. alfonso morone • architect, associate professor of industrial design, at the university of naples federico ii department of architecture. his research activity is mainly focused on the cultural relationship between quality and industrial design. references al-ayash a., kane r. t., smith d. 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(2007) “effects of indoor colour on mood and cognitive performance,” building and environment, vol. 42, 3233–3240. cultura e scienza del colore color culture and science 37 cultura e scienza del colore color culture and science | 06 | 2016 issn 2384-9568 1chiara gregoris chiara.gregoris@libero.it 1iuav university of venice colour and light in communication of fabric façades abstract modern society is characterised by the high speed at which objects, people, information and news move. architecture has little choice but to adapt to the times in which it is expressed and evolve on that basis. therefore, it is in a position today more than in the past to act as a vehicle for information and images. the envelope is the part that is most affected by these changes; the façade is the part which relates to the outside; the visible skin that can create an interaction between architecture and user. there are many different ways to create communication on a façade: images and messages can be produced by using colours and lights, or through the movement of the elements that make up the façade itself. the aim of this paper is to take an in-depth look at the aspect of those architectural surfaces which use the characteristics of colour and light of the fabric coverings as a vehicle for communication. the history of fabric and colour have been intertwined since time immemorial, but it is interesting to observe the innovative applications that exist in the architectural field today. there are types of coloured fabrics which cover buildings and give them a new identity thanks to the semi-transparent features which make it possible to create a vanishing effect and a play on light and shadow, both in daylight thanks to bright colours, and, at night, through backlighting. a unique property of these fabrics in comparison with other materials used as coverings is the semi-transparency created by the weave of the warp: this allows the designer to choose between blocking everything out by hiding whatever is behind it, or opening it up and giving a glimpse of the outline of the building, with a light, ephemeral effect that would otherwise be difficult to obtain. using this material can create true landmarks in the territory: buildings that become reference points which are visible and identifiable from the surroundings. in the paper we intend to deepen the appearance of color and light, both natural and artificial, in the use of textile coverings on façades. keywords fabric architecture, media facade, textile materials citation: gregoris c. (2016) ‘colour and light in communication of fabric façades’, cultura e scienza del colore color culture and science journal, 06, pp. 37-46 doi: 10.23738/ccsj.i62016.03 received 12 january 2016; revised 11 may 2016; accepted 30 september 2016 chiara gregoris is an architect, founding member of the research center “eterotopie” and fse research fellow at the university iuav of venice. she deals with research and planning on the themes of environmental quality and advanced technology for the architectural envelope, with a focus on sustainable thematic of textiles and ceramics for architectural coatings italian translation provided: ‘il colore e la luce nella comunicazione delle facciate tessili’ 38 cultura e scienza del colore color culture and science | 06 | 2016 | 37 46 gregoris c. issn 2384-9568 doi: 10.23738/ccsj.i62016.03 1. introduction modern society is characterised by the high speed at which objects, people, information and news move. architecture has little choice but to adapt to the times in which it is expressed and evolve on that basis. therefore, it is in a position today more than in the past to act as a vehicle for information and images. the envelope is the part that is most affected by these changes; the façade is the part which relates to the outside; the visible skin that can create an interaction between architecture and user. there are many different ways to create communication on a façade: images and messages can be produced by using colours and lights, or through the movement of the elements that make up the façade itself. the aim of this paper is to take an in-depth look at the aspect of those architectural surfaces which use the characteristics of colour and light of the fabric coverings as a vehicle for communication. the history of fabric and colour have been intertwined since time immemorial, but it is interesting to observe the innovative applications that exist in the architectural field today. there are types of coloured fabrics which cover buildings and give them a new identity thanks to the semi-transparent features which make it possible to create a vanishing effect and a play on light and shadow, both in daylight thanks to bright colours, and, at night, through backlighting. a unique property of these fabrics in comparison with other materials used as coverings is the semi-transparency created by the weave of the warp: this allows the designer to choose between blocking everything out by hiding whatever is behind it, or opening it up and giving a glimpse of the outline of the building, with a light, ephemeral effect that would otherwise be difficult to obtain. using this material can create true landmarks in the territory: buildings that become reference points which are visible and identifiable from the surroundings. an example of use of the coloured fabric as a wrap is the dietrich untertrifaller architecten building in lustenau, austria. the architects have created a landmark for the surrounding area by wrapping the enormous rectangular building with a continuous sheet of polyester coated in pvc, printed on all sides with a work by the austrian artist, peter kogler. at night, the floodlit wrap gives the building an identity and makes it visible, transforming it into a strong, distinctive symbol for the area. other very interesting examples are distinguished by the use of coloured fabric during architectural 1. introduzione la società odierna è caratterizzata dalla grande velocità con cui si muovono cose, persone, informazioni e notizie. l’architettura non può che adeguarsi all’epoca in cui si esprime ed evolversi in base ad essa; pertanto si presta, maggiormente oggi che in passato, ad essere veicolo per informazioni ed immagini. è l’involucro ad essere la parte maggiormente interessata a questi cambiamenti, la facciata è la parte che si relaziona con l’esterno, la pelle visibile che può creare interazioni tra architettura e utente. la comunicazione in facciata si può ottenere in molti modi diversi; immagini e messaggi possono essere creati utilizzando colori, luci, o con la movimentazione degli elementi che compongono la facciata stessa. in questo paper si intende approfondire l’aspetto delle superfici architettoniche che utilizzano come veicolo di comunicazione le caratteristiche cromatiche e luminose dei rivestimenti tessili. la storia del tessuto e quella del colore sono intrecciate da tempo immemore, ma risulta interessante osservare le applicazioni innovative che esistono oggi in campo architettonico. esistono esempi di tessuti colorati che ricoprono gli edifici donando ad essi una nuova identità grazie alle caratteristiche di semitrasparenza che consentono di creare effetti smaterializzati e giochi di luce e ombre sia di giorno, grazie ai colori cangianti, sia di notte, mediante la retroilluminazione. una proprietà unica dei tessuti rispetto ad altri materiali utilizzati come rivestimento è la semitrasparenza conferita dal tipo di intreccio dell’orditura del tessuto; ciò permette al progettista di scegliere tra la totale chiusura, nascondendo tutto ciò che sta dietro, o l’apertura, facendo intuire la sagoma dell’edificio, con un effetto leggero ed effimero difficile da ottenere altrimenti. l’utilizzo di questo materiale può creare veri e propri landmark nel territorio, edifici che diventano punti di riferimento visibili e riconoscibili per l’intorno. un esempio di utilizzo del tessuto colorato come rivestimento è l’edificio dei dietrich untertrifaller architecten a lustenau in austria. gli architetti, infatti, creano un landmark per l’ambiente circostante rivestendo l’enorme parallelepipedo che compone l’edificio con un telo continuo in poliestere spalmato pvc, stampato su tutti i lati con un’opera dell’artista austriaco peter kogler. di notte il rivestimento illuminato conferisce al volume identità e visibilità tali da renderlo un segno forte e distintivo nel territorio. altri casi molto interessanti si caratterizzano per l’uso di tessuti colorati negli interventi di riqualificazione architettonica, nuova costruzione 39 cultura e scienza del colore color culture and science | 06 | 2016 | 37 46 colour and light in communication of fabric façades issn 2384-9568 redevelopment work, new construction or urban improvement, such as the project for the copenhagen concert hall by jean nouvel. in this new building project consisting of a main auditorium and three smaller areas, the wrap takes on considerable importance by contrasting the freer forms inside it and by rising up like a cobalt blue monolith which envelops the buildings. the system supporting the façade is covered by a glass fibre/polyester fabric with an open weave which allows you to see through it and for the air to circulate. at night, the building undergoes a dramatic transformation: images are projected onto the wrap, turning it into a media screen which is visible from afar. 2. fabric on façades: environmental quality and welfare coverings have been used as protection against the sun since time immemorial and are still being studied and used experimentally in the field of architecture. thanks to its lightness and flexibility, fabric can be used to explore new forms and solutions which can be adapted to the demands of contemporary lifestyle. in the first half of the twentieth century, with the advent of the modern movement and new opportunities in the building industry (large glass surfaces, steel structures allowing you to cover large lights, etc.) architectural envelopes have gradually disappeared, leaving only a glass surface as the boundary between inside and out. at the same time, however, the demands for quality of living comfort and a focus on energy aspects have increased. the need, therefore, is to shield from sunlight, darken, ventilate and protect from cold using “systems which allow variable, controlled modulation” [1]. shielding and kinetic technology have been perfected at the same time as the development of the technology for façades, using fabric made from different materials: natural, synthetic, metallic, composites or intelligent. the aim is to create a shield for façades that can guarantee internal comfort and well-being for those using the building, by ensuring energy savings and creating stimulating variations that can capture the attention of those on the outside of the building. the enormous potential promised by technology using fabrics has encouraged research to take an in-depth look at these topics by investigating materials and innovative systems that make it possible to improve their features and reduce time and costs at the same time. e valorizzazione urbana, come nel progetto del copenhagen concert hall di jean nouvel. in questo progetto di nuova costruzione, composto da un auditorium principale e tre spazi più piccoli, risulta di rilevante importanza l’involucro, che si contrappone alle forme più libere dell’interno ergendosi come un monolite blu cobalto che ingloba gli edifici. il sistema di supporto della facciata è ricoperto da un tessuto in fibra di vetro/poliestere a tessitura larga, che permette la visuale e il passaggio dell’aria. di notte l’edificio cambia completamente aspetto, l’involucro viene proiettato e diventa un grande schermo mediatico visibile anche dalla grande distanza. 2. tessili in facciata: qualità ambientale e benessere la tela come sistema di protezione solare è utilizzata fin da tempi antichissimi ed è tuttora oggetto di studio e sperimentazione in campo architettonico. grazie alle sue caratteristiche di leggerezza e flessibilità il materiale tessile può essere impiegato per esplorare nuove forme e soluzioni, in grado di adattarsi alle richieste dello stile di vita contemporaneo. nella prima metà del novecento, con l’avvento del movimento moderno e delle nuove potenzialità del settore edificatorio (le grandi superfici vetrate, le strutture in acciaio che consentono di coprire grandi luci, ecc.) si è verificata una progressiva dissoluzione dell’involucro architettonico lasciando come unico limite tra interno ed esterno una superficie vetrata. allo stesso tempo, però, sono aumentate le esigente qualitative di comfort abitativo e di attenzione all’aspetto energetico; le necessità dunque sono quelle di schermare dall’irraggiamento solare, oscurare, ventilare, proteggere dal freddo utilizzando “sistemi che permettono una modulazione variabile e controllata”[1]. parallelamente allo sviluppo delle tecnologie di facciata, si sono perfezionate quelle schermanti e i sistemi di tipo cinetico, che utilizzano tessuti realizzati con materiali diversi: naturali, sintetici, metalli, compositi o intelligenti; il fine è quello di creare delle schermature di facciata che siano in grado di garantire il comfort interno e il benessere dei fruitori dell’edificio, garantendo allo stesso tempo il risparmio energetico e creare stimolanti variazioni in grado di catturare l’attenzione di chi sta all’esterno dell’edificio. le grandi potenzialità che promettono le tecnologie che utilizzano i tessili, hanno spinto la ricerca ad approfondire questi argomenti investigando su materiali e sistemi innovativi che permettano di migliorarne le caratteristiche 40 cultura e scienza del colore color culture and science | 06 | 2016 | 37 46 gregoris c. issn 2384-9568 doi: 10.23738/ccsj.i62016.03 “the innovative structures formed by tensile membranes have the potential to produce significant benefits in terms of efficiency and environmental sustainability, however, they can also create a more flexible, comfortable and welcoming relationship between people and the architecture that they use. [...] the advantages of flexibility, adaptability and mobility in an architectural project are substantial and may prove to be important components in future strategies of building design”.[2] fabric façades can offer various solutions to this problem as they are able, depending on the size of the mesh formed by the weft and the warp, to diversify how much light permeates, from total darkness to visual transparency. blackout fabrics that do not allow any light to pass are mainly technical fabrics with a close weave, often coated with protective elements which enhance this feature. these composite materials, in addition to preventing the light filtering through, are quite impermeable to air and water as well, and resistant to atmospheric agents. the materials that are used also have different approaches to colour: the ones made from polyester fibre/pvc (polyvinylchloride) offer the greatest range of colours, while glass fibres coated with ptfe (polytetrafluoroethylene) or silicone only come in a limited range of colour. due to the high production temperature, the pigments must be extremely resistant and in most cases this material is either sandy grey, which is the colour it has at the end of the production cycle, or white. expanded ptfe comes in various shades while etfe membranes are mostly transparent or white, but can also be printed on. the ability to be printed on is, in fact, another important property of various fabrics. the easiest one to print on is polyester/pvc. the etfe is imprinted with a special system for fluoroplastics while glass fibres/silicone and glass fibres/ptfe cannot be printed on directly, although systems are being devised to allow these composite fabrics to be coated with printed film.[3] in addition to blackout fabrics, there are also filtering fabrics (or screens) which have an open weave that allows light to permeate and you to see through them, more or less clearly, depending on how open the weave is. filtering fabrics, which can also be made of metal, are often chosen to create light, ephemeral coverings that, in contrast to the solidity of the buildings, can create interesting and unexpected juxtapositions. metal netting in particular has been chosen for many projects. the colours used are basically the natural colours of metal: grey, copper or e al contempo ridurne i tempi e i costi: “le strutture innovative formate da membrane in tensione hanno la potenzialità di produrre notevoli benefici in termini di efficienza e sostenibilità ambientale, tuttavia, possono anche sviluppare una relazione più flessibile, confortevole e ricettiva tra le persone e l’architettura che esse utilizzano. [...] i vantaggi della flessibilità, adattabilità e mobilità nel progetto di architettura sono sostanziali e sono in grado di dimostrarsi componenti importanti nelle strategie future della progettazione degli edifici”.[2] i tessuti in facciata possono offrire svariate soluzioni a questo problema in quanto sono in grado, a seconda dell’apertura della maglia formata da trama e ordito, di diversificare la permeabilità alla luce, da un oscuramento totale alla trasparenza visiva. i tessuti completamente oscuranti, che non permettono il passaggio della luce, sono principalmente tessili tecnici con un’orditura chiusa, spesso spalmati con elementi che ne proteggono e accentuano le caratteristiche. questi materiali compositi, oltre ad impedire alla luce di filtrare, presentano una buona impermeabilità anche all’aria e all’acqua e resistenza agli agenti atmosferici. i materiali che vengono utilizzati presentano anche differenti approcci al colore: quello costituito da fibre di poliestere/pvc (polivinilcloruro) è quello che offre il maggior range di colori, mentre le fibre di vetro rivestite in ptfe (politetrafluoroetilene) o in silicone si presentano in un numero limitato di colori; a causa dell’elevata temperatura nella produzione i pigmenti devono essere estremamente resistenti e nella maggior parte dei casi questo materiale si presenta grigio sabbia, che è il colore che ha nel momento in cui esce dalla filiera, o bianco. il ptfe espanso si può trovare in diverse tonalità, mentre le membrane in etfe sono prevalentemente trasparenti o bianche, ma possono essere stampate. un’altra proprietà importante dei vari tessuti è appunto la possibilità di venire stampati. quello che presenta la maggior facilità di stampaggio è il poliestere/pvc, l’etfe viene impresso con un sistema apposito per le fluoro-plastiche, mentre le fibre di vetro/silicone e le fibre di vetro/ptfe non possono venire stampate direttamente, ma si stanno studiando sistemi per fare in modo che questi tessuti compositi possano venire ricoperti con dei film stampati.[3] oltre ai tessuti oscuranti ci sono anche i tessuti filtranti (o screen), che mostrano una tessitura aperta; consentono il passaggio della luce e permettono la visuale, più o meno 41 cultura e scienza del colore color culture and science | 06 | 2016 | 37 46 colour and light in communication of fabric façades issn 2384-9568 similar. the support can also be painted after installation with coloured paints in any shade. the distinctive or polished aspect bestowed on the fabric allows it to reflect the light in a very different way compared to traditional fabrics, by creating shimmering, mirror-like, iridescent surfaces. these characteristics can also be enhanced or changed at night with the aid of coloured lights that create a media surface which can transmit images and information like on a screen. this technology is used in “mediamesh” netting that incorporates led lights in the stainless steel metal mesh modules which can produce images without obstructing the view from the inside towards the outside, thanks to the high degree of open weave in the mesh. 3. fabric wraps on an urban scale 3.1. building envelopes as a communication media in an urban context the building envelope in today’s society and culture occupies a twofold role, both as a barrier between the inside and the outside (i.e. between the set of spatial elements that must ensure the fulfilment of user requirements and the environmental system) and as a means of communication. the evolution of the perception of time and communication is reflected on the outer skin of architecture that becomes a support for images, information and messages while simultaneously attempting to become increasingly light and flexible: “the buildings envelopes that best represent our times appear more and more to consist of iridescent skin surfaces which can be controlled and modified. often they can be transformed by actively involving the new users/spectators [...]. speed, immediacy, spontaneity, interactivity, variability and ubiquity are just a few of the aspects that characterise the skin of these buildings.”[3] the lightness manages to create the feeling of an ephemeral and intangible envelope which, depending on the characteristics of the fabric itself, may allow the outline of the building or some elements of it to be glimpsed while guaranteeing protection from direct sunlight. the fabric, however, can also be completely opaque, with different applications and uses: for example, in urban and suburban contexts, it is commonplace to use protective canvases on building sites as supports for images and commercials. the building site is, indeed, a temporary element definita, a seconda dell’apertura della maglia stessa. i tessuti filtranti, che possono essere anche metallici, vengono spesso scelti per realizzare rivestimenti leggeri ed effimeri che, contrapponendosi ad edifici massicci, possono creare contrasti interessanti ed inaspettati. in particolare le reti metalliche sono state scelte per molti progetti. i colori utilizzati sono tendenzialmente quelli naturali del metallo: grigio, rame o simili, il supporto può, inoltre, venire tinto dopo l’installazione con vernici colorate di qualsiasi tonalità. la sua peculiarità, che può ottenere un effetto cromato o lucido, dona al tessuto la possibilità di riflettere la luce in maniera molto diversa dai materiali tessili tradizionali, creando superfici vibranti, riflettenti e cangianti. le caratteristiche, inoltre, possono essere valorizzate o cambiate di notte, con l’ausilio di luci colorate che creano una superficie mediatica con la possibilità di trasmettere immagini e informazioni come in uno schermo. questa tecnologia viene utilizzata per la rete “mediamesh” che incorpora alla rete metallica in acciaio inox moduli led rgb in grado di creare immagini e allo stesso tempo permettere la visuale dall’interno verso l’esterno grazie ad un alto grado di apertura nell’orditura del tessuto. 3. rivestimenti tessili a scala urbana 3.1. involucri comunicativi nel contesto urbano l’involucro edilizio nella società e nella cultura contemporanea si pone nel duplice ruolo di barriera tra interno ed esterno (cioè tra l’insieme di elementi spaziali che devono garantire il soddisfacimento delle esigenze dell’utenza e il sistema ambientale) e di strumento di comunicazione. l’evolversi della percezione del tempo e della comunicazione si riflette sulla pelle dell’architettura che diventa supporto per immagini, informazioni e messaggi, cercando, al contempo, di diventare sempre più leggera e flessibile: “gli involucri degli edifici che maggiormente possono rappresentare il nostro tempo appaiono sempre più spesso costituiti da superfici a pelle cangiante, controllata e variabile. sovente essi sono in grado di trasformarsi coinvolgendo attivamente i nuovi fruitori/spettatori [...]. la velocità, l’immediatezza, l’istantaneità, l’interattività, la mutevolezza, l’ubiquità, sono solo alcuni degli aspetti che caratterizzano la pelle di questi edifici.”[3] 42 cultura e scienza del colore color culture and science | 06 | 2016 | 37 46 gregoris c. issn 2384-9568 doi: 10.23738/ccsj.i62016.03 that creates an imbalance in the image of a city; monochromatic white canvases that are used to protect the scaffolding create mute surfaces that are out of step with their surroundings. potentially these canvases can become decorative, colourful paintings of enormous dimensions that communicate with the city. these large membranes that often cover buildings during restoration work simulate the idea of changing the “guise” of the building: what is hidden temporarily turns into something else on the canvas, allowing architecture to innovate by changing image. moreover, in addition to being able to print on canvases, you can project onto them, creating temporary urban screens that interact at night with the public. “contemporary urban space seems to have become a place where all types of communication technology can be experimented: from adhesive polychrome coverings (known as films or decorative films) and advertising backdrops that cover scaffolding, scattered over building sites for urban restoration in which the materials used are increasingly advanced and convey a sense of visual dynamism, to experimentation with more well-known electronic scoreboards and video walls”[4] 3.2. colour, light and innovation canvas and colour are an undisputed binomial, demonstrated by centuries of masterpieces in painting. in the field of architecture, the canvases used to cover façades of inferior buildings do not offer a great variety of colours or patterns: the shades for monochromatic canvases are mostly white or beige, although striped awnings are commonly installed over most of the windows in our suburbs (about 95% overall). the traditional methods of dyeing fabrics for external use are immersion, with the application of seams and differentiation between the colours of the fibres, whereas printing by heat transfer and digital printing are the most innovative. innovation, however, is also making headway in the field of lighting. fabrics used for projections or which are backlit are commonplace, but there are already others on the market that integrate devices for light and colour, such as interwoven leds creating true luminous supports. optic fibres are integrated into the synthetic fibres (quite often nylon) in these fabrics, connected to the edges of the fabric with leds that project the light inside, thus creating variations in brightness and colour. thanks to the use of new printing and lighting technologies, fabric wraps can be used for research and artistic and cultural exploration, but printed fabrics or those with lights are not the only fields of experimentation for fabric la leggerezza riesce a creare la sensazione di un involucro effimero e inconsistente e, a seconda delle caratteristiche del tessuto stesso, può permettere di intravedere la sagoma dell’edificio o degli elementi che lo compongono, garantendo allo stesso tempo la protezione ai raggi solari diretti. il tessuto, però, può anche essere completamente opaco, con applicazioni e utilizzi diversi: ad esempio nei contesti urbani e periferici è largamente diffuso l’uso di servirsi dei teli di protezione ai cantieri come supporti per immagini e spot pubblicitari. il cantiere, infatti, è un elemento temporaneo che crea un disequilibrio nell’immagine della città; i teli monocromatici bianchi, che servono per la sicurezza dei ponteggi, definiscono superfici mute in disarmonia con l’intorno. la potenzialità di questi teli è diventare decorativi, quadri colorati di dimensioni enormi che comunicano con la città. queste grandi membrane che rivestono gli edifici, spesso durante i restauri, simulano l’idea di cambiare “veste” all’edificio, temporaneamente ciò che è nascosto si trasforma in qualcos’altro nella tela, permettendo all’architettura di rinnovarsi cambiando immagine. inoltre i teli, oltre ad essere stampati, possono essere proiettati, creando schermi urbani temporanei che interagiscono nottetempo con le persone. “lo spazio urbano contemporaneo sembra diventato luogo di sperimentazione di tutti i tipi di tecnologie atte a comunicare: dai rivestimenti adesivi policromi (conosciuti come film o pellicole decorative) ai teli pubblicitari che rivestono i ponteggi sparsi nei cantieri di restauro cittadini, i cui materiali impiegati sono sempre più evoluti tanto da dare un senso di dinamicità alla visione, fino alle sperimentazioni più conosciute di tabelloni elettronici e videowall”[4] 3.2. colore, luce e innovazione tela e colore sono un binomio assodato, dimostrato da secoli di capolavori in pittura; in campo architettonico la tela impiegata nei rivestimenti di facciata nell’edilizia minore non ha grandi varietà di colori o di fantasie: le tinte prevalenti per le tele monocromatiche sono il bianco o il beige; in alternativa possiamo notare l’ampissimo uso di tende rigate (per una percentuale di circa il 95% del totale), che campeggiano sopra le finestre di gran parte delle nostre periferie. i metodi tradizionali di colorazione dei tessuti ad uso esterno sono ad immersione, con applicazione di cuciture e differenziazione tra i colori delle fibre; più innovativi sono lo stampaggio per trasferimento di calore e la stampa digitale. 43 cultura e scienza del colore color culture and science | 06 | 2016 | 37 46 colour and light in communication of fabric façades issn 2384-9568 wraps, there is also movement. in addition to guaranteeing energy-savings and sustainability, fabric façades that move are proposed as media façades using technology and movement to create screens for information and art on a large-scale. the lightness of the fabric allows unique, new configurations; the possibility of playing with colours through natural and artificial light (in the daytime and at night), by letting it filter through or blocking it out, increasingly enhances the design and artistic opportunities for these types of systems. 3.3. application examples of luminous and colourful fabric façades that relate to the surroundings the use of fabric coverings, combined with an innovative use of light and colours, can create installations and works of art which relate, not only to the users of the building, but to the entire surrounding area and the people passing by. there are numerous examples of fabric coverings which have taken on the role of landmarks: sculptures of coloured light that rise up in cities or landscapes and become points of reference radiating out from the place in which they are installed. just such an example is walch’s event catering center by dietrich/untertrifaller architekten in lustenau, austria. the building, situated in open countryside, is a huge rectangular building entirely covered with a micro-perforated, ht polyester yarn, precontraint membrane coated in pvc. the material is stretched and fixed to a steel substructure about one metre off the ground to create an effect of being suspended. the fabric is printed all over with a design by the austrian artist, peter kogler. it protects the interior from direct sunlight and at the same time allows a view of the surrounding countryside. in fact, seen from the inside, the material is virtually transparent. kogler’s design gives the impression that the surface is rippled and creates an illusion of movement, so that we are unable to make out the exact size of the building. at night, the covering is illuminated on all sides and the printed pattern seems to emerge from the contours of the building. in the daytime, the pattern seems to consist of shades of grey while, at night, the colours become brighter and vary from pale blue to an intense blue/purple. at night, the building becomes a landmark: a sculpture of light visible from far away that stamps a strong mark on the territory.[6] another example of a landmark that, unlike the previous example, is located in an urban context is the copenhagen concert hall by jean nouvel. l’innovazione, però, si sta spingendo anche verso il campo dell’illuminazione. molto diffusi sono i tessuti utilizzati per le proiezioni o retroilluminati, ma ne sono già in commercio altri che integrano dispositivi luminosi e colorati, ad esempio led, nelle trame dell’ordito, creando veri e propri supporti luminosi. a questi tessuti sono integrate alle fibre sintetiche (spesso di nylon), fibre ottiche, collegate ai bordi del tessuto con led che proiettano la luce all’interno, creando variazioni luminose e cromatiche. grazie all’utilizzo di tecnologie nuove di stampaggio e illuminazione i rivestimenti tessili possono proporsi come luoghi di ricerca ed esplorazione artistica e culturale, ma non sono solo i tessuti stampati e luminosi i campi di sperimentazione nell’ambito dei rivestimenti in tessuto, ma anche il movimento: oltre a garantire gli aspetti energetici e sostenibili, le facciate cinetiche tessili si propongono come media-facciate, che usano la tecnologia e il movimento per realizzare schermi informativi o artistici a scala urbana. la leggerezza del tessuto permette configurazioni nuove e uniche; la possibilità di giocare con i colori attraverso la luce naturale e artificiale (di giorno e nottetempo), facendola filtrare o impedendone il passaggio, arricchisce ancora di più le occasioni progettuali e artistiche di queste tipologie di sistemi. 3.3. esempi applicativi di facciate tessili colorate e luminose che si rapportano con l’intorno l’uso di rivestimenti in tessuto, coniugato ad un innovativo utilizzo di luce e colori, è in grado di creare installazioni ed opere artistiche che si relazionano non solo con i fruitori dell’edificio, ma con tutto il contesto circostante e le persone che vi transitano. esistono svariati esempi di rivestimenti tessili che acquistano il ruolo di landmark, sculture di luce colorata che si ergono nelle città o nei paesaggi e che diventano punti di riferimento radiali del luogo stesso in cui sono installati. uno di questi esempi è il walch’s event catering center di dietrich/untertrifaller architekten a lustenau, austria. l’edificio, situato in un contesto libero e agreste, è un enorme parallelepipedo rivestito interamente con una membrana microforata in poliestere ht precontrait spalmato pvc. il materiale è teso, fissato ad una sottostruttura in acciaio e si stacca di circa un metro da terra, per creare un effetto di sospensione. il tessuto è stampato interamente e su tutti i lati con un disegno dell’artista austriaco peter kogler: esso protegge l’interno dall’intrusione dei raggi solari diretti, permettendo al contempo la visuale sul paesaggio circostante; infatti, visto dall’interno, il materiale risulta pressoché 44 cultura e scienza del colore color culture and science | 06 | 2016 | 37 46 gregoris c. issn 2384-9568 doi: 10.23738/ccsj.i62016.03 the project aims to become the cornerstone in regenerating the surrounding urban area: a social, cultural and economic catalyst. in this case as well the building is a distinct geometric figure covered by an envelope consisting of glass fibre/polyester and blue cobalt polyacrylate. the rigour and linearity of the fabric envelope are in contrast, however, with the complexity of the internal structures: the aim of the project is to be a tribute to the philharmonie concert hall created by hans scharoun in berlin in 1963. the concept of the envelope project is to create a media surface that conveys the opportunities for communication and interaction offered by the integration of the it system and the façade. during the day, the precontraint fabric, fixed to a tensile structure of steel beams and cables, allows you to see the outlines of the inner hall and the people moving about on various levels, figure 1walch’s event catering center, dietrich/untertrifaller architekten (photo: dietrich/untertrifaller) figura 1 figure 2copenhagen concert hall, jean nouvel (photo: seier+seier) figura 2 trasparente. il disegno di kogler causa l’impressione che la superficie sia increspata e crea un’illusione di movimento che fa perdere la capacità di definire le corrette dimensioni dell’edificio. nelle ore notturne la tela viene illuminata su tutti i lati e il disegno stampato sembra uscire dai contorni del fabbricato. se di giorno il disegno è composto da sfumature di grigio, di notte i colori si fanno accesi e variano dall’azzurro pallido al blu/viola intenso. l’edificio di notte diventa un landmark, una scultura luminosa visibile dalla lunga distanza che imprime un segno forte nel territorio.[6] un altro esempio di landmark che, a differenza dell’esempio precedente, si trova in un contesto urbano è la copenhagen concert hall di jean nouvel. il progetto si propone di diventare un fulcro in grado di rigenerare l’area urbana circostante, 45 cultura e scienza del colore color culture and science | 06 | 2016 | 37 46 colour and light in communication of fabric façades issn 2384-9568 in addition to the outline of the building itself; at night moving images, works of visual art, messages and commercials are projected onto the fabric façade. the cobalt blue, rectangular building, that seems both solid and ephemeral, can be considered a landmark, making the place where is located instantly recognisable while creating new dynamics in an urban context.[7] 4. conclusions “colours are the way in which surfaces appear to us. if today, therefore, an important part of the messages that condition us is conveyed in colour, this means that the surfaces have become important vehicles for messages. walls, screens, surfaces in paper, plastic, aluminium, glass, and fabric etc. have become an important media.” [8] this statement by flusser clearly sums up the concept of the media aspect of architectural surfaces. images are perceived by humans in a much more intuitive way that the written word; in contemporary society where everything moves very quickly, invaded by signals and advertising, the key to communication seems to be just this: image which finds the ideal and optimum way of expressing itself through colour. funding the research on which this article is based was supported by iuav university of venice research fellow “i-mesh for facades. architectural integration of textile solar shading systems for environmental sustainability” conflict of interest no financial or personal interest have affected my objectivity, there are no potential conflicts of interest including financial, personal or other relationships with other people or organizations within three years of beginning the submitted work that could inappropriately influence, or be perceived to influence my work. bibliography [1] leg. decree 311/2006 [2] kronenburg, robert “flexible architecture and mensile membranes”, in tensinet symposium 2007, ephemeral architecture, time and textiles, clup, milano, 2007 [3] koch, michel “membrane structures: innovative buildings with film and fabric” prestel, munich, 2004 [4] zennaro, pietro “il colore della contemporaneità” in il un catalizzatore a livello sociale, culturale ed economico. anche in questo caso l’edificio è un volume geometrico definito rivestito da un involucro composito in fibra di vetro/poliestere e poliacrilato di colore blu cobalto. il rigore e la linearità dell’involucro tessile si contrappongono, però, alla complessità delle strutture interne, il progetto vuole essere un tributo alla philarmonie realizzata da hans scharoun a berlino nel 1963. il concetto del progetto dell’involucro è di creare una superficie mediatica che esprime le possibilità comunicative e di interazione offerte dall’integrazione tra l’informatica e il sistema di facciata. di giorno il tessuto precontraint, fissato ad una struttura di travi d’acciaio e cavi in tensione, permette di vedere i contorni della sala interna e delle persone che si muovono sui vari livelli, oltre alla sagoma dell’edificio stesso; di notte sulla facciata tessile vengono proiettate immagini in movimento, opere di visual art, messaggi e spot pubblicitari. il parallelepipedo blu cobalto, che pare tanto massiccio quanto effimero, può essere considerato un landmark che dona riconoscibilità al luogo in cui si trova e che crea nuove dinamiche nel contesto urbano.[7] 4. conclusioni “i colori sono il modo in cui ci appaiono le superfici. se, dunque, oggi una parte importante dei messaggi che ci programmano è veicolata a colori, ciò significa che le superfici sono diventate importanti portatrici di messaggi. pareti, schermi, superfici di carta, plastica, alluminio, vetro, tessuto ecc. sono diventate «media» importanti.”[8] questa affermazione di flusser riassume chiaramente il concetto di mediaticità delle superfici architettoniche. le immagini sono comprensibili nella percezione umana in modo molto più intuitivo che i testi scritti; nella società contemporanea, dove tutto è veloce, invaso da segnali e pubblicità, la chiave della comunicazione sembra essere appunto l’immagine, che trova nel colore il mezzo ideale e preferenziale per esprimersi. 46 cultura e scienza del colore color culture and science | 06 | 2016 | 37 46 gregoris c. issn 2384-9568 doi: 10.23738/ccsj.i62016.03 colore dei materiali per l’architettura, atti del convegno di studi, (“the colour of contemporary times” in the colour of materials for architecture, papers of the study conference) edizioni progetto padova, padova, 2004 [5]gasparini, katia “superfici in mutazione. luci e colori in movimento nell’architettura contemporanea” (“changing surfaces. light and colour in movement in contemparary architecture”) in il colore nella produzione di architettura, iperedizioni, verona, 2008 [6] pell, ben “the articulated surface: ornament and technology in contemporary architecture”, birkhauser gmbh, basel, 2010 [7] “copenhagen concert hall” in module no. 350 april 2009 [8] flusser, vilèm “la cultura dei media” (“media culture”), bruno mondadori editori, milan, 2004 cultura e scienza del colore color culture and science cultura e scienza del colore color culture and science | special issue on food color | 05 | 2016 55 issn 2384-9568 food perception without colors 1anna poli annamaria.poli@unimib.it 1dipartimento di scienze umane per la formazione “riccardo massa”, università degli studi di milano bicocca abstract if we are going to discuss the importance of color in food we cannot overlook that part of the world population has not trichromatic vision – with reference to those who see colors differently or who don’t see any colors at all. in this article i try to put myself in the shoes of someone who don’t see any colors of food or who cannot see them properly. i shall try to see through the eyes of a person unable to perceive colors – an anomalous trichromacy –– exploring and describing, when possible, the numerous visual-perceptive problems. these people have a limited access to the meanings mediated by colors in our society. citation: poli a. (2016) ‘food perception without colors’, cultura e scienza del colore color culture and science journal, special issue on food and colour, 05, pp. 55-61, doi: 10.23738/ccsj.i52016.07 received 08 september 2015; revised 11 january 2016; accepted 22 january 2016 cultura e scienza del colore color culture and science | special issue on food color | 05 | 2016 | 55 61 56 poli a. issn 2384-9568 doi: 10.23738/ccsj.i52016.07 1. color in normal vision and its importance in food perception color has important consequences on appearance, packaging and consumption of food that can be coherently studied/addressed only in the case of people with trichromatic vision people who perceive colors properly. color is related to food in many ways – from production to sales, display to purchase, quality control to actual consumption. the color of a food is usually considered one of the main factors that decide how a consumer, specially a person with trichromatic vision, takes into account when assessing its quality, and it is a very important spoilage indicator in food preservation at home, and in the quality of control during the food industry processes: the color food changes in the presence of bioactive compounds. sant’anna, deyse gurak, damasceno ferreira, and tessaro, in their review of studies tracking bioactive compounds with colour changes in foods describe (2013) describe with the cielab parameters and colorimetric instrumentation, how the change of colors food tracks bioactive components [1]. however, there are many psychological aspects tied to the color of food too. fergus m. clydesdale, in his study entitled color as a factor in food choice (1993), note that the color of a food influences a person’s perception of which one they will enjoy compared to another. color plays a key role in the selection of food, even influencing its flavor: the visual perception of color, when there is too much in a food, can even replace sugar. it influences judgments on the intensity of the taste, on the amounts of sweetness and pleasantness, so it becomes a decisive factor governing food preferences. [2] 2. introduction to normal color vision mechanisms colors are the visual perceptive sensations resulting from the electro-photo-chemical activity generated by a light signal (photon) which enters the eye and is picked up by the retinal photoreceptors (retinal nerve cells), absorbed and processed photo-chemically to convert it to electrical impulses that are sent to the brain. at each frequency in the visible spectrum of electromagnetic radiation, certain wavelengths and intensities are associated with the visualization of a given color. [3.4] the resulting colors are not due only to the reflection of a certain photon on nearby objects or surroundings, but to the light rays which, as isaac newton demonstrated, are ever-present in the air throughout our planet a [5]. color has been described as the result of processes taking place in our eyes and brain – a quality of our visual-perceptive sensation, though the result also depends on the physical properties of the source lighting the bodies we see [6]. however, color vision and perception in poor or good light depend on two main factors: first of all the integrity and health of cones the retinal nerve cells, where the cones receive electromagnetic signals from the frequencies in the visible spectrum; these establish the main condition for colors to be perceived by the human visual system. the second factor is that there must be no lesions in the brain areas responsible for visual-perceptive function, where the electric impulses generated by the retinal cells arrive [7]. 3. varieties of human color vision human beings see colors in a variety of ways; most people have trichromatic vision, so-called normal color vision. in ophthalmology, the trichromatic vision or trichromatism describes the human color vision based on three kind of receptor protein through cone receptors that absorb short, medium and longer wavelengths light (blue, green and red) of the visual spectrum [8]. nevertheless there are other forms of human color vision too. there are some people in the world who have a different “readability” of physical reality due to functional/physiological or anatomical anomalies of their body, congenital alterations or caused by traumatic events [9]. their experiences of the world are the result of sensations associable to an uncommon knowledge. people with different color vision are defined anomalous trichromatic, so-called also color blindness. they have congenital or acquired color vision characterized by an another sensitivity to the colors and they don’t clearly distinguish the colors of the visible spectrum. the anomalous trichromatic people are defined by the receptive problems of one kind of cones, due to the absence of one of three photopigments [10]. the cones contain three specific photo-pigments sensitive to wavelengths of electromagnetic radiation: eritrolabe is sensitive to red, clorolabe is sensitive to green and cianolabe is sensitive to blue. the cones, control the reception of the wavelengths, absorb the maximum luminous intensity of the three primary colors (red, green, blue). the classification of color vision alterations arises from the following conditions: • protanopia is the red blind = absence a the radiations referred in the visible spectrum, corresponding to electromagnetic radiation between 380 nm (violet) and 780 nm (red); cultura e scienza del colore color culture and science | special issue on food color | 05 | 2016 | 55 -61 57food perception without colorsc issn 2384-9568 of eritrolabe; • tritanopia is the blue blind = absence of cianolabe; • deuteranopia is the green blind = absence of clorolabe; • protanomaly is red weak sensitivity; • deuteranomaly is green weak sensitivity; • tritanomaly is blue weak sensitivity; • tetrachromacy are people, specifically women, who see a four-dimensional space of colors, they have an extra photopigment, with which they distinguish among mixture of spectral colors [11]. other people have monochromacy or achromatopsia, these color vision alterations or color blindness are related to functional anomalies on two cones or the complete atrophization of cones. in the visual process these conditions generate heavy problems to distinguish two or three primary colors: respectively monochromacy is the partial achromatopsia and the vision in greyscale is a complete achromatopsia. the complete achromatopsia is distinguished in retinal achromatopsia due to retinal congenital anomalies and in cerebral achromatopsia in this case is an acquired achromatopsia caused by anomalies in visual cortex area. different cases are cited in the literature and compared, for example the artist jonathan i. whose life narrated by oliver sacks [12] and that of the patient of dr. antonio damasio [13]. the incidence of people color blindness is different and varied among the ethnicity of the different geographical regions of the world and the color blindness is genetically trasmitted. in the u.s.a., approximately one person in 33.000 is achromate [14]. 4. color vision anomalies and difficulty in food perception it is extremely interesting to study people with an achromatic visual perception, especially if the topic is tackled from different angles. since complete achromates cannot distinguish colors they fail to see why they are useful, or why society has attributed such value to them throughout history. the ways colors are used by society still influence the visual perception of those who cannot see the color, or only see it partially or differently. every day these people find themselves faced with visual-perceptive barriers resulting from inappropriate use of color – not advantageous for everyone. people with achromatopsia have not been much studied as well as the study of their attitudes that require a systematic deep analysis of their needs in everyday life, if we are to design different ways of using color so that its message is accessible to everyone. on this topic ludwig wittgenstein noted that “we speak of “colour-blindness” and call it a defect. but there could easily be several differing abilities, none of which is clearly interior to the other [15]. and remember, too, that a man may go through life without his colour-blindness being noticed, until some a special occasion brings it to light.” people with achromatopsia cannot identify food, or any other visible thing, on the basis of its color. this limitation depends on their different types of achromatopsia, they see the world from at least three different visual-perceptive viewpoints: the complete achromates can only see things in greyscale, while partial achromates have monochromatic vision of either in red scale or in blue scale [16]. complete and partial achromatopsia are due to a lack of the ability to see or perceive respectively three or two primary colors and the colors formed when they are combinedb. both achromatopsia are not progressive, and are caused by congenital malformations or degenerative changes to the cells of the retina. the diagnosis is based on an anomaly detected in a photopic electroretinogram (erg) which in a person with achromatopsia shows the absence or reduction of the ability to distinguish colors. moreover are used also test with ishihara tables and osterberg charts, and the test of colored crayons, grids green and red to match the color of pastel used and estimate the percentage of the corresponding color [17]. however, the achromates may also suffer other visual problems: they may have low visual acuity (from 1/20 to 2/10), photophobia, an horizontal nystagmus – which is an involuntary oscillation of the eyes or squinting, taking the form of continually screwing up one’s eyes to avoid bright light, and a central scotoma. they generally have problems focusing details and their sight is often interrupted by white flashes when too much light hits their eyes, so they are constantly worried by a lack of information about their surroundings, that can sometimes disorient them. this conditions are not true when the achromate has an acquired achromatopsia caused by anomalies or trauma in visual cortex area (cerebral achromatopsia). it is certainly not easy to live in a world without color, seeing it only in greyscale and experiencing all its aspects – practical and functional as well as cultural – without being able to rely on the messages it conveys, especially because nowadays color has meanings for all the world’s cultures, often serving as a common language b see the information of the associazione acromati italiani onlus at the website http://www.acromatopsia. it. reference is made in particular to visual perception problems involving color vision. in the usa one person in 12 has some sort of problem and there is a strong imbalance towards males (8%) compared with only 0,4% of females. cultura e scienza del colore color culture and science | special issue on food color | 05 | 2016 | 55 61 58 poli a. issn 2384-9568 doi: 10.23738/ccsj.i52016.07 [18]. just think what sensory expressions are used to describe all the features of food, for example in the contest of wine drinking, the use of wine color vocabulary (ruby-red) to describe the characteristics of types of wine [19]. what semantic approach to the terminology and perception of food can a person use if they can’t see colors? adjectives that everyone can grasp may have to be selected so as to provide sensory experiences to ensure social integration and inclusion. every day the media carries messages that are mostly designed and produced in colors intended for people with trichromatic vision, and when an image is presented as colorless there is usually a reason – a predefined meaning. thus in all cultures colors form an expressive visual code, as a content that adds detail and information to the surroundings, improving people’s perceptive and descriptive quality; they are signs and symbols that raise the quality of human reality and experience [20]. 5. compensations given by texture, shapes, and cross-modal perception people with trichromatic vision can see every things better, but as achromates have not got this visual aid they have to ‘develop’ their own visual perception strategies to make up for this different view of reality. not having enough visual elements to deal with everyday life, achromates have to compensate the lack of color with other codes of expression. they undoubtedly use other sensory channels in the attempt to educate their visual perception abilities by identifying other typical visual ‘markers’. these may include ‘tonal vibrations’ for certain color mixes, or special sensitivity to texture, which even though seen only in greyscale, or monochromatically, can still provide sensory information useful for building up alternative ways of orienting their visual perception more appropriately. people who see colors know and remember how certain colors are associated with certain objects, or with reality in general. the achromate, however, has to associate things with shapes and textures ‘visualized’ only in greys, and therefore has no experience of the multiple cultural messages conveyed by color. but to get back to the main topic, it is precisely because color supplies so much perceptive and visual information that one wonders what achromates really see when they look at food. what relationship have they got with food? what effects does this lack of color perception have on their nutrition? these are the first questions that arise at the very start of a study on the color needs of people who have to live without color. this raises many problems not just involving the appearance of food, where seeing only in greyscale certainly does not make it easy for an achromate to immediately recognize and identify an item. there are other practical questions, such as how can a color-blind person visually check the quality of a food, to see whether it is altered or contaminated. it clearly appears that checking the quality of a food is largely based on the visual-perceptive assessment of its color as an effective and practical ‘tool’ for an immediate estimate of its bioactive ingredientsc [21]. but this cannot work for an achromate, who can only base his judgment on texture as his ‘tool’. the texture facilitation in food perception regarding primarily the people with an high or medium visual acuity that allows a fine perception of the elaborate features of texture food. in this conditions the perception of texture food could be compensated for lack or absence of color. the people with acquired achromatopsia (cerebral achromatopsia) could exploit this perceptive compensation. this facilitation doesn’t apply to people with partial or complete achromatopsia where their visual acuity is low. an interesting study by katsunori okajima, junya ueda and charles spence investigated the effects of vision of texture on the perception of food. they maintain that color and shape of a food influence the perception of its flavor and combine in the formation of the taste; they also note, however, that the texture of a food is important, contributing to the perception of the food. these researchers have developed an augmented reality (ar) system which can change visualization of the texture of a food in real time; one can see how textures influence the perception of aroma and flavor. their findings indicate that the perception of a food can be affected by changes in light intensity and texture is unrelated to any color change; when it does not suggest any particular attribute for the food, it may reflect more complex individual experiences relating to the responses of the various sensorial areas [22]. vision of textures therefore play a large role in the perception of food, especially if they are combined with shapes and colors, which are the main visual features explaining people’s associations and preferences in the perception of flavor and aroma [23]. clearly, for people who cannot see colors shape and textures provide the main visual information for identification. consequently the sensations and visual perceptions of achromates cannot be based on known associations tested directly through the sensorial experience of people who see in color. since how an individual relates to food differs depending on the person’s physical and genetic features, how do achromates relate to food without the interference of the color code, which c this study covers a broad spectrum of food products, analysing their biochemical components, phenols, carotenoids, chlorophyll, and betalaine, to highlight the correlations between the presence of these ingredients and the changes in the color of foods during storage in the industrial productive process. cultura e scienza del colore color culture and science | special issue on food color | 05 | 2016 | 55 -61 59food perception without colorsc issn 2384-9568 is believed to be fundamental in the recognition, attraction and differentiation of what we eat and drink? how does visual perception in greyscale affect the achromate’s sensorial and physiological systems? just think how our physiological signals of hunger and desire for food are influenced by its color. then too, sensory perception of the colors of food affects our appetite and the stimulation of gastric juices [24]. but if a person lacks the sensorial perception of food colors does the stimulation of gastric juices always rely on the visual channel? very probably the olfactory route compensates to a large extent. verhagen and engelen, using functional magnetic resonance bioimaging, have thoroughly investigated the neurocognitive basis of sensorial integration in humans, especially food perception [25]. this perception involves multiple signals that enter the body through different sensorial channels, creating combinations of sensations as they cross it [26]. these processes have been amply studied in connection with synesthetic perception in humans [27]. 6. open issues (emotions, research to be done, etc.) from the psychological viewpoint we must not underestimate how colors relate to emotion [28]. one wonders, therefore, whether an achromate reacts emotionally to the sight of food. it seems likely that these people’s emotions when faced with food are aroused not through the visual channel but through the olfactory channel. so it is smell that evoke the emotions and pleasure associated with food in an achromate more than a person with trichromatic vision. even so, the lack of visual perception of color still has certain effects on a person’s perception of tastes and odors. how is the color of food related to its flavor and smell? interesting among the many studies of these aspects is research by chen, jianshe, eaton, and louise on the perception of creaminess in food by people with trichromatic vision [29]. these results illustrate the importance of extending these studies to achromates and people with other color vision anomalies to find out how seeing something creamy in greyscale is related to its taste, or its smell, bearing in mind that too is associated/ translated into the gradations of grey of the image. if the room is lit well enough, an achromate can identify a food on the basis of its shape and texture, either in greyscale or in the scale of red or blue, though the outlines may seem blurred and hard to distinguish clearly, and so do the textures, unless the person uses some sort of magnifying equipment. quite probably an achromate cannot recognizes a food immediately, and has many difficulties because of his multiple visual impairments. a person with trichromatic vision would be sensorially disoriented to have to appreciate the smell and taste of a food only from the perception of greyscale. equally disorienting is the sensory combination of the tactile perception of materials that a person can visually associate only with colorless texture, or of sounds with no chromatic correspondence [30]. antonio damasio in his book the feeling of what happens. body and emotion in the making of consciousness: “… a man’s identity is rooted in his body… we know the world through the senses of our body…” [31] the mechanisms of sensations produced in humans by stimuli detected by sight, smell, taste, hearing and touch act in an integrated multimodal fashion even in people who are color-blind. however, their perceptive experience seems more complex though at the same time simpler, relying on subtle nuances or visual ‘vibrations’ that are not immediately perceptible to a person with normal color vision. ernst mach in his widely-known the analysis of sensations, believes that “…it is not our bodies that generate sensations but the complexes of sensations that form bodies. it is not the things but the colors, sounds, pressures, spaces and times – which we normally call sensations – that are the real elements of the universe”. to some extent i share these concepts as the complexes of sensations form bodies but only to the extent that the bodies have no difficulty receiving the stimuli that generate them – what he calls the real elements of the universe [32]. the perceptive modalities of an achromate, however, are certainly more complex: from the visual-perceptive viewpoint in the greyscale are something less than all the colors, and some gradations of color look much the same when translated into gradations of grey as it is only the ‘color tone’ that makes the difference. however, it is the intersensorial result of parallel perceptions and the compensations through other sensory channels that ‘form the bodies’ of achromates. the first studies on compensations through other sensory channels dated back to the historical observations of aristotele in de anima where he alleged the existence of parallelism between the grave sound frequency perception and the refraction of light, in the medieval age with the first conceptualization of synaesthesic cultura e scienza del colore color culture and science | special issue on food color | 05 | 2016 | 55 61 60 poli a. issn 2384-9568 doi: 10.23738/ccsj.i52016.07 phenomenon through to the eighteenth century. in 1704 isaac newton in opics asserted the correspondence between the colors of the light spectrum and the musical scale through a mathematical relation between the seven colors of the light spectrum and the sound frequencies on which the musical scale was based. the concept of the cross-modal perception and the intersensorial perceptive strategies changed in the different ages until today with the modern studies on synesthesia and the neural plasticity and new development [33]. the synesthesia defined from the intersensorial relations and synesthetic evocations is a modality of exploration approach to the physical world used by everybody and the compensative needs of achromates have a major weight than people with normal vision. sensations, like perceptions, are faculties that imply the presence of an human body [34], but we know very little about how a human body is formed when it cannot feel certain sensations, or even evoke them. what are the sensations that form that body? how can they be reinforced? it would be extremely interesting to understand what happens to the human body and how it responds from the neuro-psycho-physiological viewpoint when it receives – or does not receive – the electromagnetic signals from its surroundings; this would help us understand the meaning of the intersensoriality, parallel perceptions and the synesthetic approach implicit in humans [35]. each of these areas would be a worthwhile field for research and study with the aim of helping extend our knowledge of the perceptive strategies of achromates and people with other color visual defects, so that in the future we might be able to propose solutions to enable them to overcome their visual-perceptive obstacles. our aim here is to arouse the reader’s awareness of the numerous problems in the life of those who do not see things in full trichromatic detail, and whose everyday life, therefore is dotted with obstacles that could probably be dismantled if we knew more and paid more attention to their needs. achromates live their lives, expressing themselves linguistically and communicating sensations and perceptions without being able to make any reference to color. we need to study what roles color plays in their perceptive and neuro-psycho-physiological mechanisms. color is an information code which is not just a matter of culture, but is a signal people use, a stimulus to which the neuro-psycho-physiology of the human body reacts automatically. bibliography [1] sant’anna v., deyse gurak p., damasceno ferreira marczak l., tessaro i.c., tracking bioactive compounds with colour changes in foods a review, in “dyes and pigments”, sept. 2013, vol.98, no. 3, pp 601-8. [2] f. m. clydesdale, color as a factor in food choice, in critical reviews in food science and nutrition, 1993, vol.33(1), p. 83-101, taylor & francis group. [3] p. gouras, the perception of colour, macmillan, basingstoke, 1991; [4] d.c. burr fiorentini, m.c. morrone, “temporal characteristics of colour vision: vep and psychophysical measurements”, in a. valberg lee bb. eds., from pigments to perception: advances in understanding visual processes, plenum press, new york, 1991, n. 203, pp 139150. [5] i. newton, opticks a treatise of the reflections, refractions, inflections & colours of light, dover publications, new york, 1952. [6] a.c. guyton, j.e.hall, textbook of medical physiology, elsevier saunders, philadelphia, pa, 2011. [7] a. poli, cinema e disabilità visive, franco angeli, 2009. [8] a.c. guyton, j.e.hall, op.cit, 2011; l. maffei, a. fiorentini, arte e cervello, zanichelli, bologna, 1995. [9] oliver sacks, an anthropologist on mars, a.a. knopf, new york, 1995, and from the same author see: the island of the colorblind, a.a. knopf, new york, 1997. [10] m. gussoni, g. monticelli, a. vezzoli, dallo stimolo alla sensazione. fisiologia degli organi di senso, casa editrice ambrosiana, milano, 2006. about color vision pictures simulation of the types of color blindness see also the website: www.colourblindawareness.org. [11] f. wilczek, a beautiful question. finding nature’s deep design, penguin books, london, 2015, pp 154-156 [12] o. sacks, op. cit., 1995. [13] a. damasio, the feeling of what happens. body and emotion in the making of consciousness, harcourt brace 1999. [14] d. r. nirula, c.g. saha, the incidence of color blindness among some school children of pokhara, western nepal, nepal med college journal 2010, 12(1), pp 48-50. [15] l. wittgenstein, remarks on colour, (edit by ) g.e.m. anscombe, basil blackwell, oxford, 1977, part iii – 36. [16] f. futterman (edited by), living with achromatopsia, a publication for the achromatopsia network, berkeley, ca 2004; f. futterman (edited by), understanding and coping with achromatopsia, a publication for the achromatopsia network, berkeley, ca 2004; see also a. poli, op. cit., 2009. [17] j. birch, diagnosis of defective colour vision, oxford university press, new york, 1993. [18] h. zollinger, color: a multidisciplinary approach, verlag helvetica chimica acta, zürich, 1999; j. gage, color and meaning. art, science, and symbolism, university of california press, berkeley and los angeles, ca, 1999. on color anthropological linguistics study see w. a. foley, color, in anthropological linguistics: an introduction, cultura e scienza del colore color culture and science | special issue on food color | 05 | 2016 | 55 -61 61food perception without colorsc issn 2384-9568 blackwell publishing, oxford, uk, 1997, pp 150-165. [19] c. diederich, sensory adjectives in the discourse of food: a frame-semantic approach to language and perception, john benjamins publishing company, amsterdam, 2015, pp 19-21. [20] j. gage, color and culture. practice and meaning from antiquity to abstraction, university of california press, berkeley and los angeles, ca, 1993. [21] v. sant’anna, deyse gurak, l. damasceno, m. ferreira, i. c. tessaro, tracking bioactive compounds with colour changes in fooda review, in dyes and pigments, volume 98, issue 3, sept. 2013, pp 601–608, elsevier ltd. uk; [22] k. okajima, j. ueda, c. spence, effects of visual texture on food perception, in journal of vision, july 2013, vol.13, issue 9, p. 1078-1078. [23] michal kuniecki, joanna pilarczyk, szymon wichary, the color red attracts attention in an emotional context. an erp study, in frontiers in human neuroscience, april 2015, vol.9, pp 1-14. [24] l. b. sørensen ; p. møller ; a. flint ; m. martens ; a. raben, effect of sensory perception of foods on appetite and food intake: a review of studies on humans, in international journal of obesity, 2003, vol.27(10), nature publishing group, p. 1152. [25] j. v. verhagen, l. engelen, the neurocognitive bases of human multimodal food perception: sensory integration, in neuroscience and biobehavioral reviews, 2006, vol.30(5), pp 613-650. see also c. huerta, pr sarkar, tq duong, ar laird, pt fox, neural bases of food perception: coordinatebased meta-analyses of neuroimaging studies in multiple modalities, in obesity, 2014 jun, vol.22(6), pp 1439-1446. [26] y. maric, m. jacquot, , contribution to understanding odour–colour associations, in ninth pangborn sensory science symposium, food quality and preference, elsevier ltd, march 2013 27(2): pp 191-195. [27] r. e. cytowic, synesthesia: a union of the senses. new york, ny, springer-verlag,1989; see also v. niccolai, j. jennes, p. stoerig, t. m. van leeuwen, modality and variability of synesthetic experience, amer j psych, vol. 125, no. 1 (spring 2012), pp. 81-94, university of illinois press, article found on the website: http://www.jstor.org/ stable/10.5406/amerjpsych.125.1.0081 . [28] m. kuniecki, j. pilarczyk, s. wichary, the color red attracts attention in an emotional context. an erp study, in frontiers in human neuroscience, april 2015, vol.9, pp 1-14. [29] j. chen, l. eaton, , multimodal mechanisms of food creaminess sensation, in food & function, 2012, vol.3(12), pp 1265-1270. [30] j. gage, the sound of colour, in color and culture. practice and meaning from antiquity to abstraction, university of california press, berkeley and los angeles, ca, 1993, pp 227-246. [31] a. damasio, op. cit., 1999. [32] e. mach, the analysis of sensations, and the relation of the physical to the psychical, dover publications inc., new york city, new york, 1959, p. 2 [33] f. ceglie, the concept of synaesthesia in the late nineteenth an early twentieth century, in history & philosophy of psychology, (2007), vol. 9 (2), 57-61, british psychologycal society; a. alfaro, a. bernabeu, c. agullo, j. parra, e. fernandez, hearing colors: an example of brain plasticity, frontiers in systems neuroscience, 04/2015 doi:10.3389/fnsys.2015.00056, the full text is available in digital format at website: https://www.researchgate.net/ pubblications/275257286_hearing_colors_an_example_ of_brain_plasticity [34] on this topic see: e. r. kandel, j. h. schwartz, t. m. jessell, fondamenti delle neuroscienze e del comportamento, casa editrice ambrosiana, milano, 1999; also see m. gussoni, g. monticelli, a. vezzoli, op. cit., 2006, and c.f. michéa, du délire des sensations, labé libraire de la faculté de médicine, 1846, the full text is available in digital format on the website: http://babel.hathitrust.org/ cgi/pt?id=nyp.33433011466905 [35] r. e. cytowic, the man who tasted shapes, the mit press, cambridge ma, 2003; j. harrison, synesthesia. the strangest thing, oxford university press, new york, 2001. cultura e scienza del colore color culture and science 35 cultura e scienza del colore color culture and science | 08 | 2017 issn 2384-9568 desirée sabatini desiree.sabatini@uniroma1.it ivano forte ivanoforte@gmail.com ilma schiavitti ilma.schiavitti@gmail.com mauro sabatini maurosabatini.91@gmail.com alessio pietrini alessio.pietrini91@gmail.com department of art and performing arts, sapienza university of rome italian translation provided: il recupero del colore originale dei materiali d’archivio: la correzione digitale del colore dello storico discorso antisemita del duce, nel 1938 the recovery of the original colour of the archive material: the digital colour correction of the ancient antisemitic discourse of the duce in 1938 abstract the work in question is a digital colour correction experiment on a 35 mm film, a documentary from the archivio storico luce. this is the speech pronounced by benito mussolini in piazza dell’unità, in trieste, on september 18th, 1938. the film is a positive duplicate made in nitrate of cellulose, scanned in full hd with resolution 1920 x 1080 at 25 fps. the interventions, with the help of the software pfclean, were aimed to solve problems related to a strong flickering and a lack in distribution of light and dark gradations, which led to a faded and low-contrast image. in order to bring back to life the initial splendor, the digital intervention was performed using both historical and technical information. our first goal was to keep the colouring and lighting of an outdoor shot, with a shot in full day that detects strong contrasts of light. further, we tried to recover part of the original colour with a colour correction aimed to globally adjust the brightness and the gradation of black and white, while on the more faded photograms a contrast mask was applied. the applied interventions have allowed the documentary to return to the right gradation of light with qualitative results that are comparable to the original image. keywords light; colour; full hd; contrast; gradation; colour correction; contrast; documentary; mussolini; archivio; luce; digital; film; restoration; speach; dark; black; white; positive; nitrate; trieste; 35 mm; pfclean; citation: sabatini d., forte i., schiavitti i., sabatini m., pietrini a. (2017) ‘the recovery of the original colour of the archive material: the digital colour correction of the ancient anti-semitic discourse of the duce in 1938’, cultura e scienza del colore color culture and science journal, 08, pp. 35-46, doi: 10.23738/ccsj.i82017.03 received 7 july 2017; revised 20 october 2017; accepted 13 november 2017 desirée sabatini, is doctor of research in history, theory and technique of theatre and spectacle at the “sapienza” university of rome and research assistant for the project: “the theatrical audiovisual. documentation and identification of digital show restoration methodologies“ disciplinary scientific sector l-art / 05, at dams, disciplines of visual arts, music, entertainment and fashion, link campus university. she was the coordinator for the master’s in digital technologies at the faculty of arts and philosophy at the same university, where was also a research fellow and visiting professor lecturing on the history of the digital restoration of images and film. ivano forte is a video editor and camera operator with a degree in audiovisual sciences and a master’s degree in video and audio editing from la sapienza university of rome. he has worked as a senior editor and archivist at the cta (centro teatro ateneo), one of the most important university archives in italy, and has contributed to the digitalization, archiving, and transfer of rare cta materials within the multi-year eclap project, the new online archive for the performing arts in europe, funded by the european commission. ilma schiavitti, is a digital film restoration professional at augustus color, a company with 40 years experience in audio and video postproduction, providing the whole range of video services for the audio-visual industry. previously, ilma worked as digital restoration artist for l’immagine ritrovata. she graduated from sapienza università di roma with a degree in “arti e scienze dello spettacolo” and a master degree in digital audio/video restoration. mauro sabatini graduated in audiovisual sciences from la sapienza university in rome, where he lives; he uninterruptedly studies the relationship between the film industry and cultural heritage, and currently works as a post-production operator in augustus color, a laboratory dedicated to digital restoration as well as, today, to the development and printing of films. he writes about italian contemporary theater studying the influence of the cinema’s imaginary on visual performance on the “new theater made in italy” web platform curated by valentina valentini. alessio pietrini lives and works in rome, where he studied cinema and digital arts at la sapienza university. after a work experience in the university’s audiovisual archive he undertook a course of theoretical and professional training in the field of film restoration. in particular, he concentrated his interests on the application and in the comparative analysis of the most important digital restoration software. 36 cultura e scienza del colore color culture and science | 08 | 2017 | 35 46 sabatini d. et al. issn 2384-9568 doi: 10.23738/ccsj.i82017.03 1. introduction colour is one of the main problems when faced with a film and video restoration work but, at the same time, it is also the main reason for restoring it. not by chance, colour correction, a key factor in the digital intermediate process, is now also considered the central stage of the entire restoration work, since it allows the film to re-acquire the right light gradation with quality results comparable to the original image and therefore closer to the artist’s vision. not always, however, one focuses on the scientific investigation preceding the colour correction, which instead contributes significantly to the success of the subsequent digital intervention; we refer to the steps of analysing the original media and therefore, as in the case study that we want to submit here, to the classification of the film type, the supervision of the scanning [1] and conversion of signals from analogue to digital, technical features that are added with the digital operator’s examination, who only with all these elements is able to choose the algorithms dedicated to restoring the original colour and subjectively manipulate the parameters available. taking into consideration an analytical study of all these factors, it is possible to apply a correct method of digital colour restoration avoiding the falsification of the original colour. the digital colour correction experiment presented here concerns a 35 mm film, which is part of a precious and special collection: this is a historical documentary of the “archivio figure 1 documentary on benito mussolini’s speech in trieste, original frame. figura 1 documentario sul discorso di benito mussolini a trieste, fotogramma originale. 1. introduzione il colore rappresenta uno dei principali problemi da affrontare quando ci si trova di fronte ad un lavoro di restauro cinematografico e video ma, allo stesso tempo, è anche il principale fattore per cui viene operato un restauro. non a caso la color correction, centrale nel processo del digital intermediate, viene oggi considerata anche la fase centrale dell’intero lavoro di restauro, permettendo al film di riacquisire la giusta gradazione di luce con risultati qualitativi paragonabili all’immagine originale, e quindi più vicini alla visione dell’artista. non sempre, però, ci si sofferma sull’indagine scientifica precedente alla correzione colore, che invece contribuisce notevolmente sulla riuscita del successivo intervento digitale; ci si riferisce alle fasi di analisi del supporto originale e quindi, come nel case study che si vuole presentare, alla classificazione della tipologia della pellicola, alla supervisione del processo di scansione [1] e della conversione dei segnali da analogici a digitali, caratteristiche tecniche che si sommano conseguentemente con l’esame dell’operatore digitale, che solo con tutti questi elementi è dunque in grado di scegliere gli algoritmi dedicati al ripristino del colore originale e manipolare soggettivamente i parametri a disposizione. prendendo in considerazione uno studio analitico di tutti questi fattori è possibile dunque applicare una corretta metodologia del restauro digitale del colore senza commettere delle falsificazioni della colorazione originale. 37 cultura e scienza del colore color culture and science | 08 | 2017 | 35 46 the recovery of the original colour of the archive material: the digital colour correction of the ancient anti-semitic discourse of the duce in 1938 issn 2384-9568 storico luce”. luce is one of the internationally renowned archives and keeper of the vast film and photographic heritage produced in italy, especially in the period between 1925 and 1965 [2]. these are mainly non-fiction products, and therefore news, documentaries and repertoire, which may not always be subject, due to their content and technical features, to the commonly adopted digital colour correction of films. regarding the content, this is quite a special occasion: the historical speech given by benito mussolini in piazza dell’unità, in trieste on september 18, 1938; it is an original copy of the medium-length film, other than the one kept in the luce archives, where there are no images of what is in fact the crucial moment of all the irredentist itinerary of mussolini. indeed, when mussolini starts his speech from the raised stage in front of the government building, a cut suddenly projects the viewer after the end of the speech, with the duce going to the shipyard fabbrica macchine sant’andrea, for the normal continuation of its itinerary. we do not know if this gap is the result of a precise choice in the editing of the time or it is a cut made later. certainly, this curious absence is connected with the decade old question about the lack of concrete documents produced or preserved by luce regarding the antisemitic turn of the fascist regime. the archive has, however, recently recovered a positive duplicate that, at the end of the 1970s, the archivio cinematografico nazionale della resistenza (national resistance cinema archive) of turin had acquired from a private collector, which features the 18 minutes absent in the original negative, the only surviving filmed testimony figure 2 documentary on benito mussolini’s speech in trieste, original frame. figura 2 documentario sul discorso di benito mussolini a trieste, fotogramma originale. l’esperimento di correzione digitale del colore che si presenta ha come oggetto una pellicola 35 mm., che fa parte di una collezione preziosa e particolare: si tratta di un documentario storico dell’archivio storico luce, uno degli archivi più noti a livello internazionale e custode del vasto patrimonio filmico e fotografico prodotto in italia, soprattutto nel periodo tra il 1925 e il 1965 [2]. si tratta di prodotti soprattutto non di fiction, e quindi cinegiornali, documentari e repertorio, che non sempre possono sottostare, per natura di contenuto e realizzazione tecnica, alla metodologia cinematografica più diffusa per la correzione del colore digitale. per il contenuto è da considerarsi prioritaria la particolarità del girato, si tratta dello storico discorso pronunciato da benito mussolini in piazza dell’unità, a trieste, il 18 settembre 1938; è una copia originale del mediometraggio diversa da quella conservata presso gli archivi del luce, dove non sono presenti le immagini relative a quello che è difatti il momento cruciale di tutto l’itinerario irredentista di mussolini. infatti, quando mussolini dà inizio al proprio discorso dal palco rialzato posto davanti al palazzo del governo, un taglio proietta all’improvviso lo spettatore già a discorso terminato e con il duce diretto verso il cantiere navale fabbrica macchine sant’andrea, per il normale proseguimento del suo itinerario. non sappiamo se questa lacuna sia dovuta ad una precisa scelta nel montaggio dell’epoca o se si tratti di un taglio posteriore all’originale del negativo; certo è che questa curiosa assenza si relaziona con il decennale interrogativo sulla mancanza di concreti documenti realizzati o conservati dal luce intorno alla svolta antisemita del regime fascista. l’archivio ha però di recente recuperato un duplicato positivo che alla fine 38 cultura e scienza del colore color culture and science | 08 | 2017 | 35 46 sabatini d. et al. issn 2384-9568 doi: 10.23738/ccsj.i82017.03 of the racial politics of the fascist regime. this implies, unless this is a working copy, an initial printing of the full speech and a later surgical cut made in the middle of the original negative. from a more technical point of view, therefore, this is a positive duplicate (35 mm) in cellulose nitrate: conserved under fortuitous circumstances for many decades prior to the acquisition into the archive, it has suffered a hugely negative impact on the quality of the film; in addition to dirt and dust, almost all of frames are subject to defects and abrasions of the emulsion and the support, with significant loss of photochemical image. there are countless white vertical lines in multiple consecutive frames throughout the film, often caused by the projector’s sprocket teeth, and, as a sign of repeated public projections, subjected to constant light pumping as well as damaged joints, due to the coarse overlapping of film sections or glue or scotch tape residues used to make the junctions; there are also tears and lacerations that occasionally cross the entire frame area. these poorly maintenance conditions have resulted in a significant decay in image quality: whitish moisture spots are repeated throughout the film, considerable shifts of light within a frame, a clear indication of colour decay: whites and blacks are attenuated, the contrast is reduced to a minimum, making a number of frames difficult to view and sometimes giving, at times, the perception of poorly focused images. entrusted to the archivio luce, the film has been subjected to preservation operations such as joint repair and cleaning and washing of the film to remove part of the dirt. it was then scanned at full hd 1920x1080 resolution with prores codec and sub-sampling 422, making it available for digital restoration. all 35 mm films produced before 1950 were made on a highly flammable nitrate support, and the reprint on safety film has guaranteed long-term safety, but has not eliminated the problem of retaining the original medium. in addition, it is necessary to preserve the vintage copy, as it is the one that allows the transmission of the image and the only form under which the audio-visual material has come to us. this paper documents the phases that have characterised the colour correction process on the film presented; the material on which the works have been carried out is a scanned copy, as already mentioned, with full hd resolution of 1920x1080 at 25 fps. frame analysis has highlighted problems linked to a strong flicker and poor distribution of light and dark gradations, therefore creating a faded, low contrast image where medium tones prevail. to re-establish the initial splendour, the digital intervention has been performed using both historical and technical information, relating to the support, degli anni settanta l’archivio cinematografico nazionale della resistenza di torino aveva acquisito da un collezionista privato, dove sono presenti i 18 minuti assenti nel negativo originale, unica superstite testimonianza in immagini in movimento della politica razziale del regime fascista. ciò lascia intendere, a meno che non ci si trovi di fronte ad una copia di lavorazione, una iniziale stampa del discorso integrale e solo successivamente un taglio chirurgico operato nel cuore del negativo originale. dal punto di vista più tecnico si tratta, dunque, di un duplicato positivo (35 mm) in nitrato di cellulosa: conservato in modo quantomeno fortunoso per molti decenni prima dell’acquisizione in archivio, presenta ingenti danni per quanto concerne la qualità della pellicola; oltre che da incrostazioni di sporco e polvere, la quasi totalità dei fotogrammi è soggetta a guasti ed abrasioni dell’emulsione e del supporto, con rilevanti perdite di immagine fotochimica. sono visibili innumerevoli righe bianche verticali in più fotogrammi consecutivi lungo l’arco di tutto il film, spesso causati dai denti dei rocchetti di un proiettore, e possibile indizio di una sua ripetuta proiezione ad un pubblico, sottoposto ad un costante pompaggio luminoso nonché giunte danneggiate, per la grossolana sovrapposizione dei lembi della pellicola o per residui di colla o scotch utilizzati per effettuare la giunta stessa; non mancano nemmeno gli strappi e le lacerazioni che attraversano occasionalmente tutta l’area del fotogramma. le sopraccitate scarse condizioni di corretta conservazione hanno prodotto un significativo deperimento della qualità dell’immagine: macchie biancastre di umidità si ripetono lungo tutto l’arco del film, sbalzi di luce all’interno di un’inquadratura considerevoli, chiaro indizio di decadimento del colore: i bianchi e i neri sono attenuati, il contrasto ridotto al minimo, tanto da ridurre molti fotogrammi ad una visione problematica e dando, a tratti, la percezione di scarsa messa a fuoco dell’immagine. affidata all’archivio luce, la pellicola è stata sottoposta ad operazioni di preservazione come la riparazione giunte e la pulizia e lavaggio della pellicola per rimozione di parte dello sporco, e in seguito scansionata a risoluzione full hd 1920x1080 con codec prores e sottocampionamento 422, rendendola disponibile per il restauro digitale. tutti i film in 35 mm prodotti prima del 1950 sono stati realizzati sul supporto in nitrato, altamente infiammabile, e la ristampa su pellicola di sicurezza ha garantito la salvezza a lungo termine, ma non ha eliminato il problema della conservazione del supporto originale. inoltre, occorre conservare la copia d’epoca perché è quella che consente la trasmissione dell’immagine e rappresenta l’unica forma sotto la quale l’audiovisivo è arrivato fino a noi. 39 cultura e scienza del colore color culture and science | 08 | 2017 | 35 46 the recovery of the original colour of the archive material: the digital colour correction of the ancient anti-semitic discourse of the duce in 1938 issn 2384-9568 provided by the istituto luce. the frames have been restored with the pf clean software, with which it has been possible to intervene both globally, by modifying the general parameters on one or more frames, and locally, acting on certain areas, more or less large, of individual frames. various operations were required to recover part of the original colour. 2. historical notes and the editing of the documentary on september 18, 1938, in piazza dell’unità, trieste, mussolini announced the issuance of racial laws and the beginning of an active anti-semitic policy by the fascist regime, with a historical discourse focused precisely on the “jewish problem” for which it was necessary to awaken a “clear and severe racial awareness” in defence of which, following the model of hitler’s germany, segregation laws would soon be applied in italy as well. mussolini’s agitated discourse, aimed at sanctioning the definitive and irreversible racial twist in the policies of the fascist regime, welcomed by the cries of jubilation of the immense crowd gathered in piazza dell’unità, could not truly surprise the jews, bombarded for at least a year with growing anti-semitic propaganda, and who had seen the storm coming for a few weeks: in july of ‘38 there was the first publication of the race manifesto (armani, betta and fiamingo, 2007), and in the early days of september the first laws were issued, those directed against foreign jews and those that removed the jews from schools. the choice of figure 3 documentary on benito mussolini’s speech in trieste, original frame. figura 3 documentario sul discorso di benito mussolini a trieste, fotogramma originale. questo lavoro documenta le fasi che hanno caratterizzato il processo di color correction sulla pellicola presentata; il materiale sul quale si è lavorato è una copia scansionata, come già anticipato, a risoluzione full hd 1920x1080 a 25 fps. l’analisi dei frame ha evidenziato problemi legati ad un forte flickerio e una scarsa distribuzione delle gradazioni di chiaro e scuro, favorendo quindi un’immagine sbiadita, a basso contrasto dove prevalgono i toni medi. per ritrovare lo splendore iniziale, l’intervento digitale è stato eseguito utilizzando come riferimento sia le informazioni di carattere storico, sia quelle tecniche, relative al supporto, fornite dall’istituto luce. i fotogrammi sono stati restaurati con il software pf clean con il quale è stato possibile intervenire sia a livello globale, inteso come la modifica dei parametri generali su uno o più frame, che a livello locale, agendo quindi su determinate aree, più o meno grandi, dei singoli frame. per recuperare parte del colore originale sono state necessarie diverse operazioni. 2. cenni storici e montaggio del documentario il 18 settembre 1938, in piazza dell’unità a trieste, mussolini annunciò l’emanazione delle leggi razziali e l’inizio di un’attiva politica antisemita da parte del regime fascista, attraverso uno storico discorso incentrato proprio sul “problema ebraico”, di fronte al quale sarebbe stato necessario risvegliare una “chiara e severa coscienza razziale” in difesa della quale, seguendo il modello della germania hitleriana, ben presto si sarebbero applicate le leggi di 40 cultura e scienza del colore color culture and science | 08 | 2017 | 35 46 sabatini d. et al. issn 2384-9568 doi: 10.23738/ccsj.i82017.03 the city of trieste was totally intentional: in his speech, mussolini strictly linked the adoption of racial politics to the development of an imperial policy carried out by fascism. mussolini’s trip to trieste was only the first stage of a journey undertaken with propaganda clamour in the areas of world war i, naturally seen under a strongly nationalistic perspective. in trieste, among other things, there was a strong adherence to fascist nationalism, the degeneration of the old irredentist spirit of the city before it became italian. many jews in trieste were among the irredentists, and this deep conviction greatly facilitated their adhesion to the fascist ideology, as was the case in the rest of italy, when part of the jewish population saw in fascism the natural evolution of nationalism (de felice, 2005). now mussolini’s racial politics had cut them out of any sense of national belonging, tying in a definite way fascist nationalism to anti-semitic racism. the duce spoke in a city where the jewish presence was undoubtedly very strong and profoundly rooted; it was also the city from whose port ships sailed loaded with jews from the east who fled from persecution to the land of israel: the same trieste had been nicknamed the gate of zion (ovadia, 1999), and in this sense, mussolini’s choice of launching his anti-semitic turn from the historic port of the venezia giulia region was extremely symbolic. only the sound track of benito mussolini’s speech at piazza dell’unità has been for decades kept and distributed. although the operators of istituto luce had followed and recorded the duce’s journey through venezia giulia and veneto, the negative of the medium still preserved at the archives of the luce does not include the images of what was in fact the crucial moment of the irredentist itinerary of mussolini. the editing of the documentary allows the viewer to follow all the steps of the lavish arrival of the duce in the port of trieste; then it shows panoramic sequences and his transfer on a convertible car to the centre of the city: when mussolini finally reaches piazza dell’unità, and after greeting the crowd with a waving hand, he starts his talk from the raised stage in front of the palace of the government. when the plot finally gets to the top of the climax, a cut suddenly projects the viewer after the speech with the duce directed to the shipyard fabbrica macchine sant’andrea, for the normal continuation of his itinerary. a precise choice in the editing of the time? an unexpected absence, subsequent to the original cut of the negative? how does this curious absence relate to the decade-long question about the lack of concrete documents produced or preserved by the luce about the anti-semitic turn of the fascist regime? thanks segregazione anche in italia. il concitato discorso di mussolini, volto a sancire la definitiva e irreversibile svolta razziale nella politica del regime fascista, accolto dalle grida di giubilo della immensa folla radunata in piazza dell’unità, non poteva in vero cogliere totalmente di sorpresa gli ebrei, bombardati da almeno un anno di crescente propaganda antisemita, e che avevano visto scatenarsi la tempesta già da alcune settimane: al luglio del ‘38 risaliva la prima pubblicazione del manifesto della razza (armani, betta and fiamingo, 2007), e nei primissimi giorni di settembre erano state emanate le prime leggi, quelle rivolte contro gli ebrei stranieri e quelle che allontanavano gli ebrei dalla scuola. la scelta della città di trieste non fu di certo casuale: nel suo discorso mussolini legava strettamente l’adozione di una politica razziale allo sviluppo di una politica imperiale da parte del fascismo. il viaggio di mussolini a trieste era solo la prima tappa di un percorso intrapreso con clamore propagandistico nelle zone della prima guerra mondiale, viste naturalmente in un’ottica fortemente nazionalista. a trieste tra l’altro era forte l’adesione al nazionalismo fascista, degenerazione dell’antico spirito irredentista della città prima che diventasse italiana. tra gli irredentisti era stata elevata anche la presenza degli ebrei di trieste, e questa profonda convinzione facilitò di molto l’adesione degli stessi all’ideologia fascista, come accadde anche nel resto d’italia quando parte della popolazione ebraica vide nel fascismo la svolta naturale del nazionalismo (de felice, 2005). ora la politica razziale di mussolini li tagliava fuori da ogni senso di appartenenza nazionale, legando in modo indissolubile il nazionalismo fascista al razzismo antisemita. il duce parlava in una città nella quale la presenza ebraica era quindi indubbiamente molto forte e profondamente radicata nel tessuto cittadino; era inoltre la città dal cui porto salpavano navi cariche di ebrei provenienti dall’est che fuggivano dalla persecuzione verso la terra d’israele: la stessa trieste era stata soprannominata la porta di sion (ovadia, 1999), e, in questo senso, appare perciò enormemente simbolica la scelta di mussolini di lanciare la svolta antisemita proprio dallo storico porto della venezia giulia. del discorso pronunciato da benito mussolini in piazza dell’unità è stata per decenni custodita e diffusa la sola traccia audio: nonostante gli operatori dell’istituto luce avessero seguito e ripreso gli spostamenti del duce nel suo viaggio attraverso le terre della venezia giulia e poi nel veneto, nel negativo del mediometraggio tuttora conservato presso gli archivi del luce non sono pervenute le immagini relative a quello che è difatti il momento cruciale di tutto l’itinerario 41 cultura e scienza del colore color culture and science | 08 | 2017 | 35 46 the recovery of the original colour of the archive material: the digital colour correction of the ancient anti-semitic discourse of the duce in 1938 issn 2384-9568 to the exchange of information between the archivio nazionale cinematografico della resistenza (national film archive of resistance) of turin and the istituto luce, the 18-minute copy kept in turin and absent from the original negative was recovered, with mussolini’s full speech. the positive duplicate stored in turin is a 35 mm cellular nitrate film with no significant narrative gaps, with the only loss of few frames that does not interfere with the continuity of the narration. 3. the formation of the image on the film: development and fixing the documentary is impressed on a 35 mm nitrate film, whose usability is guaranteed by a photochemical process that takes place in the film itself when it is exposed to light. on the film substrate, i.e. the nitrate layer, the oldest of the media dating back to1861, when it was created with the reaction between nitric acid and cellulose flakes. it was gradually improved over time, a mixture of silver halide crystals was emulsified and dosed according to the type of film to be made. their size varied depending on the desired sensitivity of the film. such silver crystals absorb the light energy by triggering the transformation of silver in metallic silver: the crystals thus exhibit microscopic black dots in proportion to the absorbed light and are not visible to the naked eye on the film. this is defined as a latent image, since it is there but cannot be seen, so a development phase is necessary for the image to be revealed. during development, only the sensitised crystals, those affected by light, will react by turning into metallic silver and will become completely black; a greater amount of light hitting the surface of the film determines a stronger darkening. the main component for film development is the so-called detector. the development is also very sensitive to physical changes, i.e. the immersion time in the detector bath and the temperature. these two parameters are used to correct the density and contrasts in order to obtain the best photographic response. obviously, the increase in immersion time and temperature will result in increased density and contrast, while decreased time and temperature will have an inverse effect. if we have, in fact, exposed the film to excessive light we could balance that by reducing these parameters; in the reverse case of a lack of exposure, we could try to balance it by increasing those parameters. at this point, it is necessary to eliminate the crystals that have not been hit by light through a second development step, which is defined as fixing; this is a chemical treatment that allows us to stabilise the image obtained, unalterable irredentista di mussolini. il montaggio del documentario permette allo spettatore di seguire tutte le fasi dello sfarzoso arrivo nel porto di trieste del duce; seguono sequenze panoramiche e del trasferimento in auto scoperta verso il centro della città: quando mussolini raggiunge finalmente piazza dell’unità e, dopo aver salutato con un cenno della mano la folla festante, dà inizio al proprio discorso dal palco rialzato posto davanti al palazzo del governo, ovvero quando la trama si appresta finalmente a raggiungere l’apice del climax, un taglio proietta all’improvviso lo spettatore già a discorso terminato e con il duce diretto verso il cantiere navale fabbrica macchine sant’andrea, per il normale proseguimento del suo itinerario. una precisa scelta nel montaggio dell’epoca? un’assenza imprevista e posteriore all’originale taglio del negativo? in che modo questa curiosa assenza si relaziona con il decennale interrogativo sulla mancanza di concreti documenti realizzati o conservati dal luce intorno alla svolta antisemita del regime fascista? grazie allo scambio di informazioni tra l’archivio nazionale cinematografico della resistenza torinese e l’istituto luce, viene recuperata la copia torinese di 18 minuti assenti nel negativo originale, con il discorso di mussolini in forma integrale. il duplicato positivo custodito a torino è un 35 mm in nitrato di cellulosa che non presenta significative lacune narrative, ossia perdita di alcuni fotogrammi che non inficiano la continuità dell’intreccio. 3. la costituzione dell’immagine sulla pellicola: sviluppo e fissaggio il documentario è impressionato su una pellicola nitrato 35 mm, la cui fruibilità viene garantita da un processo fotochimico che avviene nella pellicola stessa quando essa viene esposta alla luce. sul supporto della pellicola, ossia il nitrato, il più antico dei supporti scoperto nel lontano 1861 per la reazione tra acido nitrico e fiocchi di cellulosa poi via via migliorato nel tempo, viene dispersa (emulsionata) una miscela di cristalli di alogenuro d’argento, la cui quantità viene dosata in base al tipo di pellicola che si vuole realizzare e le cui dimensioni variano in funzione della sensibilità della pellicola che si vuole ottenere. tali cristalli di argento assorbono l’energia della luce innescando la trasformazione dell’argento in argento metallico: i cristalli presentano così dei microscopici puntini anneriti in rapporto alla luce assorbita e che non sono visibili ad occhio nudo sulla pellicola. questa si definisce immagine latente, in quanto c’è ma non si vede, ed è quindi necessario 42 cultura e scienza del colore color culture and science | 08 | 2017 | 35 46 sabatini d. et al. issn 2384-9568 doi: 10.23738/ccsj.i82017.03 by light, by immersing the material in a fixing bath, containing substances that make silver salt soluble. transforming the silver halide crystals (insoluble) that have not been affected by light into soluble silver complexes that go from the film to the fixing bath is of paramount importance, since if these crystals are not eliminated, when exposed to light they would also slowly become metallic silver, practically destroying the image. obviously, the metallic silver crystals originated in the development process and constituting the image remain unchanged, while the silver in the fixing solution is normally recovered by electrolysis from the fixing bath itself. knowing the film in its physical characteristics by following this perspective enables us to fully understand the entire digital restoration process that will take place following the slow and progressive decay of the film, ranging from the acquisition of the material to colour correction and digital cleaning [3]. 4. the digital restoration workflow in a restoration project that begins by scanning a film, the workflow is usually based on the creation of a dpx or cineon image sequence, i.e. a sequence of uncompressed 10-bit logarithmic files that can faithfully return the information about the grey scale of the three rgb channels within the range of the film and at the same time flexible with respect to variations in information regarding colour, colour space and colour patterns. as described in section 1.2 of the “revision of ansi/smpte 268m-1994”: this flexible and resolution-independent file format describes pixel-based images with attributes defined in the header of the binary file. each file represents a single image with up to eight image elements. the image elements are defined as a single component (e.g. luma) or multiple components (such as red, green, and blue) (smpte 268m, 1992) . however, given the type of codec and format, and taking into account the machines available for the task, the restoration project in this case was set in an 8-bit linear rgb colour space. choosing a chromatic workspace is an essential step in the colour management of a project. although it is always advisable to work in a 16bit linear colour space, which provides more tones in the shadows than an 8-bit space, this type of choice has guaranteed tonal adherence to the original file without range variations; in addition, by performing operations in a linear colour space, we have avoided artefacts such as irregular edges, halos and uneven margins, passare alla fase dello sviluppo affinché tale immagine venga rivelata. durante lo sviluppo solo i cristalli sensibilizzati, quelli colpiti cioè dalla luce, reagiranno trasformandosi in argento metallico e diventeranno completamente neri; tanto più forte sarà l’annerimento quanto maggiore è stata la quantità di luce che ha colpito la superficie della pellicola. il componente principale per lo sviluppo della pellicola è il cosiddetto rivelatore. lo sviluppo, inoltre, è molto sensibile alle variazioni di tipo fisico, ovvero tempo di immersione nel bagno rivelatore e temperatura. questi due parametri vengono utilizzati per correggere la densità e i contrasti in modo da ottenere la migliore risposta fotografica. ovviamente l’aumento del tempo d’immersione e della temperatura produrranno un aumento della densità e dei contrasti, mentre la diminuzione provocherà un effetto inverso; se abbiamo, quindi, di fatto, esposto la pellicola eccessivamente alla luce potremmo aiutarci riducendo tali parametri, nel caso inverso, di una carente esposizione, potremmo tentare di recuperare aumentando i parametri stessi. a questo punto è necessario eliminare i cristalli che non sono stati colpiti dalla luce attraverso un secondo passaggio successivo allo sviluppo, che viene definito come fissaggio; si tratta di un trattamento chimico che permette di rendere stabile, quindi inalterabile alla luce, l’immagine ottenuta, immergendo il materiale in un bagno di fissaggio, contenente sostanze che rendono solubile il sale d’argento. trasformare i cristalli di alogenuro d’argento (insolubili) che non sono stati colpiti dalla luce in complessi di argento solubili che passano, in quanto tali, dalla pellicola al bagno di fissaggio è di fondamentale importanza, poiché se tali cristalli non venissero eliminati, poi, esposti alla luce, si trasformerebbero anch’essi lentamente in argento metallico, distruggendo di fatto l’immagine. ovviamente restano del tutto inalterati i cristalli d’argento metallici originati nel processo di sviluppo e che costituiscono l’immagine, mentre l’argento in soluzione nel fissaggio viene normalmente recuperato tramite elettrolisi dal bagno di fissaggio stesso. conoscere la pellicola nelle sue caratteristiche fisiche seguendo tale prospettiva consente di comprendere al meglio tutto il processo di restauro digitale che avverrà a seguito del lento e progressivo decadimento della pellicola, che va dall’acquisizione del materiale fino alla color correction e alla pulizia digitale [3]. 4. il workflow del restauro digitale in un progetto di restauro che prende il via dalla scansione di una pellicola, il work flow 43 cultura e scienza del colore color culture and science | 08 | 2017 | 35 46 the recovery of the original colour of the archive material: the digital colour correction of the ancient anti-semitic discourse of the duce in 1938 issn 2384-9568 which appear with the fusion of high-contrast and saturated colours. following the acquisition of the material, we enter the restoration phase, through which we try to bring the film as close as possible to its original status. there are essentially three different moments: analysis of the material, disturbance detection, and direct intervention with restoration tools. all this was done with the use of pfclean, a software that can offer a semi-automated initial analysis of the frames, followed by a finishing work using specific tools. the first operation that has been performed was the analysis of the reel to identify any disturbances [4]. as one can imagine, this procedure is a fundamental step for digital restoration, as it allows us to determine where and how we will need to intervene in the next steps. the second operation has been the organisation of the material, by dividing the reel into scenes through the scene cut, a process that allows us to the split the reel into clips automatically, based on the detected brightness variations. although the clips obtained in most cases correspond to actual scene changes, it is imperative to carry out a manual control to correct inaccurate cuts and to substantially customise the entire scene cutting process, based on the contents of the processed movie. these operations have allowed us to apply the right corrections based on the disturbances found. in particular, we have carried out a homogenisation figure 4 automatic deflicker intervention figura 4 intervento di de-flicker automatico figure 5 automatic deflicker intervention figura 5 intervento di de-flicker automatico è solitamente basato sulla creazione di una sequenza di immagini dpx o cineon, vale a dire una sequenza di file logaritmici a 10 bit non compressi, in grado di restituire fedelmente le informazioni relative alla scala di grigio dei tre canali rgb all’interno del gamma della pellicola e allo stesso tempo flessibili a variazioni di informazioni colore, spazio colore e modelli colore. come scritto al punto 1.2 della “revision of ansi/smpte 268m-1994”: questo file format, flessibile e a risoluzione indipendente, descrive immagini basate su pixel con attributi definiti nell’header del file binario. ogni file rappresenta una singola immagine con un massimo di otto elementi d’immagine. gli elementi d’immagine sono definiti come un singolo componente (per esempio luma) o più componenti (ad esempio rosso, verde e blu) (smpte 268m, 1992). tuttavia, dato il tipo di codec e di formato, e tenuto conto delle macchine a disposizione per il lavoro, il progetto di restauro in questo caso è stato impostato in uno spazio colore rgb lineare a 8 bit. la scelta di uno spazio cromatico di lavoro è un passo essenziale nella gestione del colore in un progetto. nonostante sia sempre consigliabile lavorare in uno spazio colore lineare a 16 bit, in modo di avere più toni nelle ombre rispetto ad uno spazio a 8 bit, questo tipo di scelta ha garantito aderenza tonale con il file 44 cultura e scienza del colore color culture and science | 08 | 2017 | 35 46 sabatini d. et al. issn 2384-9568 doi: 10.23738/ccsj.i82017.03 of brightness (medium tones, high and low lights) and of black and white gradation at the global level, while on more faded frames (mussolini’s close-ups) a contrast mask has been applied for a selective intervention. in addition, on the shots with varying light density between the frames, a filter has been applied for a more homogeneous brightness, based on a reference frame. for a first global intervention regarding the application of the restoration tools, we have chosen the deflicker tool, which has allowed us to remove the low frequency fluctuations of the image brightness from the clips. this tool has automatically analysed each frame of the clip figure 6 original frame and restored frame figura 6 fotogramma originale e fotogramma restaurato. figure 7 original frame and restored frame figura 7 fotogramma originale e fotogramma restaurato. figure 8 original frame and restored frame figura 8 fotogramma originale e fotogramma restaurato. figure 9 original frame and restored frame figura 9 fotogramma originale e fotogramma restaurato. originale senza operare variazioni di gamma, inoltre eseguendo operazioni in uno spazio cromatico lineare, abbiamo evitato artefatti quali bordi irregolari, aloni, margini sbavati, che appaiono quando vengono fusi colori a elevato contrasto e saturazione. a seguito dell’acquisizione del materiale, si entra nella fase del restauro vero e proprio con la quale si cerca di riportare la pellicola il più possibile vicino a come era in origine. si possono distinguere sostanzialmente tre momenti differenti: analisi del materiale, individuazione dei disturbi, e intervento diretto con gli strumenti di restauro. tutto questo è stato 45 cultura e scienza del colore color culture and science | 08 | 2017 | 35 46 the recovery of the original colour of the archive material: the digital colour correction of the ancient anti-semitic discourse of the duce in 1938 issn 2384-9568 to determine the necessary corrections and brightness curves; these curves were then used to manually intervene in certain areas where automatic processing failed to fully correct the brightness swings. the second global correction has been made on the black and white gradation, through the movie grade tool, in particular by combining two different adjustment modes: the first called wheel / trackball mode to directly intervene on luminance, balance, contrast and saturation; the second, histogram mode, to intervene on the overall colour range, obtaining a re-mapping of black and white points in a more or less narrow range. for a more detailed intervention on the single frame, especially on mussolini’s close-ups, we have chosen to use the sharpen tool, a contrast mask that has made it possible to provide a greater definition to the areas that appeared to be particularly faded and not contrasted enough, thus providing a greater focus and returning a sharper image. the mask has been applied in such a way as to have constant parameters in all the clips containing the duce’s close-ups. both the preservation and the digital restoration process, therefore, are applied and are considered to be fundamental insofar as long as they guarantee the possible return of the film to its original status, when it was not yet compromised by its progressive decay. the restoration work described above has been carried out within the department of art and performing arts history, sapienza university of rome, with the help of four apple imac workstations. funding this research did not receive any specific grant from funding agencies in the public, commercial, or not-forprofit sectors. conflict of interest the authors declare that nothing has affected his objectivity or independence in the production of this work. neither the authors nor their immediate family members have any financial interest in the people, topics or companies involved by this article. neither the authors nor their immediate family members had a professional relationship with the people and companies cited in this article. neither the authors nor their immediate family members are involved in a legal dispute with the people and the companies cited in this article. no conflict of interest including financial, personal or other relationship with other people and organization within three years of beginning eseguito con l’impiego di pfclean, un software in grado di offrire un lavoro semiautomatizzato iniziale di analisi dei frame, a cui fa seguito un lavoro di rifinitura finale grazie a specifici tools. la prima operazione che è stata effettuata è l’analisi del rullo al fine di individuare i disturbi presenti [4]. come si può intuire, questa procedura rappresenta una fase fondamentale per l’attività di restauro digitale, poiché permette di stabilire dove e come si dovrà intervenire nei passaggi successivi. la seconda operazione effettuata è stata l’organizzazione del materiale, tramite la suddivisione del rullo in scene attraverso lo scene cut, processo che permette la suddivisione automatica del rullo in clip, a seconda delle variazioni di luminosità rilevate. sebbene le clip ottenute corrispondano nella maggior parte dei casi ai reali cambi di scena, è comunque imprescindibile un controllo manuale che consenta una correzione dei tagli imprecisi ed una sostanziale personalizzazione dell’intero processo di scene cut, in base al contenuto del filmato elaborato. queste operazioni sono state utili per poter applicare le giuste correzioni a seconda dei disturbi riscontrati, in particolare è stata effettuata una omogeneizzazione della luminosità (mezzi toni, alte e basse luci) e della gradazione di bianco e nero a livello globale, mentre sui fotogrammi che risultavano maggiormente sbiaditi (primi piani di mussolini) è stata applicata una maschera di contrasto che ha permesso, quindi, un intervento selettivo. inoltre, sulle inquadrature che presentavano delle variazioni di densità di luce tra i vari frame di una medesima scena è stato applicato un filtro che ha permesso di rendere omogenea la luminosità, sulla base di un fotogramma di riferimento scelto. per un primo intervento a livello globale che concerne l’applicazione degli strumenti di restauro, si è scelto di utilizzare il tool deflicker con il quale è stato possibile rimuovere dalle clip le fluttuazioni a bassa frequenza di luminosità dell’immagine. con questo strumento è stato analizzato automaticamente ogni frame della clip per determinare le correzioni necessarie e le curve di luminosità; tali curve sono poi state utilizzate per intervenire manualmente su determinate aree nelle quali l’elaborazione automatica non è riuscita a correggere integralmente gli sbalzi di luminosità. la seconda correzione a livello globale è stata effettuata sulla gradazione di bianco e nero, tramite il tool film grade, in particolare utilizzando una combinazione di due differenti modalità di regolazione: la prima chiamata wheel/trackball mode per intervenire direttamente sulla densità di luminosità (luminanza), sul bilanciamento, sul contrasto e sulla saturazione; la seconda, histogram mode, per intervenire sul range totale del colore, ottenendo una ri-mappatura dei 46 cultura e scienza del colore color culture and science | 08 | 2017 | 35 46 sabatini d. et al. issn 2384-9568 doi: 10.23738/ccsj.i82017.03 the submitted work that could inappropriately influence, or be perceived to influence, this work notes [1] where it is not possible to personally follow the scanning process of the original film, it is still necessary to make sure that the technical parameters are consistent with the digital conversion of the media. [2] between 1927 and 1945, the istituto luce, founded by luciano de feo in 1924, produced the cinegiornale cinematografico luce, which provided daily news of italian life covering current affairs, politics and international news, with an inclination for war news. [3] regarding the documentary, it should be pointed out that with this term we want to indicate the digital colour correction process, omitting the aspects of colour correction in the analogue system. [4] in addition to this colour intervention, the digital restoration has included steps to stabilise the reel and remove dirt, spotting and scratches. bibliography armani, b., betta, e. and fiamingo, c. (2007). manifesto degli scienziati razzisti dossier sissco. [online] storiaestorici.it. available at: http://www.storiaestorici.it/ index.asp?art=110 [accessed 6 dec. 2017]. berolo, a., sabatini, d., bonanomi, c., gadia, d., marini, d. and rizzi, a. (2014). ‘il restauro del colore digitale: un approccio basato sull’apparenza’. cultura e scienza del colore, 1, pp.8-12. de felice, r. (2005). ‘storia degli ebrei italiani sotto il fascismo’. torino: einaudi. ovadia, m. (1999). ‘la porta di sion. trieste, ebrei e dintorni. itinerario semiserio in forma di spettacolo della presenza ebraica in città’. gorizia: libreria editrice goriziana. sabatini, d. and rizzi, a. (2011). ‘il restauro digitale del colore: esperimenti e confronti sulla memoria teatrale degli anni settanta’. colore e colorimetria. contributi multidisciplinari, vii, pp.437-442. sabatini, d. (2010). ‘il patrimonio culturale audiovisivo: il restauro digitale’. archeomatica, tecnologie per i beni culturali, iii, pp.12-16. sabatini, d. (2011). ‘restauro digitale del film. alle origini del teatro (il mnemodramma)’. fersen, itinerario ininterrotto di un protagonista del novecento, pp.102-105. smpte 268m revision of ansi/smpte 268m-1994 ‘proposed smpte standard for file format for digital moving-picture exchange (dpx), version 2.0’, revision 6.0, copyright 1986-1988, 1992, aldus corporation. filmography documentario sul discorso di benito mussolini a trieste (documentary on benito mussolini’s speech in trieste), cellulose nitrate film kept at the archivio storico luce (luce historical archive). punti di bianco e nero in un range più o meno ristretto. per un intervento più dettagliato sul singolo fotogramma, in particolare sui primi piani di mussolini, si è scelto di utilizzare lo sharpen, una maschera di contrasto che ha permesso di restituire maggiore definizione alle aree che apparivano particolarmente sbiadite e poco contrastate, dando quindi una impressione di maggiore messa a fuoco e restituendo un’immagine più nitida. la maschera è stata applicata in modo tale da avere parametri costanti in tutti i fotogrammi della clip che mostravano i primi piani del duce. tanto la preservazione quanto l’intervento di restauro digitale, dunque, nascono e si rivelano fondamentali nella misura in cui garantiscono l’eventuale ritorno della pellicola al proprio stato originario, quando essa non risulta ancora compromessa dal suo progressivo decadimento. gli interventi di restauro descritti sono stati effettuati all’interno del dipartimento di storia dell’arte e dello spettacolo, sapienza università di roma, con l’ausilio di quattro workstation apple imac. notes [1] dove non è possibile seguire personalmente il processo di scansione della pellicola originale è comunque necessario assicurarsi che i parametri tecnici siano consoni alla conversione digitale del supporto. [2] tra il 1927 e il 1945 l’istituto luce, fondato da luciano de feo nel 1924, ha prodotto il cinegiornale cinematografico luce, che rappresentava la cronaca quotidiana della vita italiana con servizi dedicati all’attualità, alla politica e alle notizie internazionali e con una predilezione per le notizie concernenti la guerra. [3] rispetto al documentario, va precisato che con tale termine si vuole indicare il processo di correzione colore digitale, tralasciando quelli che sono gli aspetti della correzione colore nel sistema analogico. [4] oltre all’intervento di colore descritto, il restauro digitale ha compreso interventi di stabilizzazione e rimozione di sporco, spuntinature e graffi. cultura e scienza del colore color culture and science 29 cultura e scienza del colore color culture and science | 07 | 2017 issn 2384-9568 michela lecca lecca@fbk.eu fondazione bruno kessler, ict technologies of vision, trento, italy using color and local binary patterns for texture retrieval abstract texture plays a crucial role to detect and recognize materials in real-world pictures. the choice of the visual descriptors that are the most appropriate for the detection and recognition tasks is generally a hard issue, due to the wide range of circumstances under which the imaged objects can appear. this work addresses the problem of the illuminant invariant texture retrieval, and it proposes two algorithms that combine illuminant invariant color information with the textural cues output by the local binary pattern (lbp) operator. the experiments, carried out on a public database, show that the joint use of color and texture features remarkably improves the retrieval performance of techniques based on lbp only. keywords image retrieval, color, texture, local binary patterns citation: lecca m. (2017) ‘using color and local binary patterns for texture retrieval ’, cultura e scienza del colore color culture and science journal, 07, pp. 29-38, doi: 10.23738/ccsj.i72017.03 received 25 january 2016; revised 08 may 2017; accepted 14 may 2017 michela lecca is a permanent researcher of the research unit technologies of vision of fondazione bruno kessler (trento, italy). her research interests include color image processing, object recognition, image retrieval and labeling, and low-level image processing for embedded vision systems. she is a member of the international association for pattern recognition iapr-girpr and of the gruppo italiano del colore-associazione italiana colore. 30 cultura e scienza del colore color culture and science | 07 | 2017 | 29 38 lecca m. issn 2384-9568 doi: 10.23738/ccsj.i72017.03 1. introduction image retrieval consists of detecting a visual correspondence between images. precisely, given a database of known images, said references, and given a (possible) new, previously unseen image, said query, the problem is to find out from the database the reference that is the most similar to the query. the visual similarity is defined as a matching function (e.g. a distance) between some visual features, like color or edges distributions, that are relevant to the retrieval task. in general, the choice of the features and of the matching function, that allow the highest retrieval performance, is a hard issue [1]. moreover, the visual features, as well as the matching function, are often required to be robust to possible image variations, such as changes of size, orientation, and light conditions. this work, that has been presented in [2] at the 10th colour conference, focuses on the retrieval of color pictures, where references and queries depict the same textured materials but acquired under different lights. precisely, this paper reports two algorithms performing colorbased illuminant invariant texture retrieval. both these algorithms describe the visual appearance of an image by combining illuminant invariant color information with the textural cues output by the local binary pattern (lbp) operator [3], and perform image retrieval by a nearest neighbor classifier. in agreement with previous works [4] [5] [6] [7], this paper empirically shows that the addition of the color features to lbps remarkably increases the retrieval performance of the techniques based on the lbp analysis only [3] [7]. the lbp operator detects image microstructures (e.g. edges, lines, flat regions), that are represented by binary vectors, called lbp, usually normalized in order to be robust against in-plane rotation of the image [3]. by definition, the lbp operator is insensitive to monotonic changes of image intensity, while invariance to chromatic illuminant changes can be obtained by computing the lbps separately on the three image channels [5], [7]. thanks to their high discrimination capability and low computational complexity, the lbp operator has been successfully applied to a wide variety of computer vision tasks, like video background subtraction [8], face detection and identification [9], fingerprints recognition [10], image classification [11]. the main issue addressed here is how to add color information by preserving the illuminant invariance of the lbps. in fact, color is one of the most important features for image description and retrieval [12], but its usage in practice is often limited due to its strong sensitivity to the light. the proposed algorithms, named gwalgorithm and vk-algorithm, cope with this problem in different ways. the gw-algorithm provides an illuminant invariant color and texture description as follows. first, it normalizes the colors of any image with the gray-world algorithm; second, for each normalized color channel, computes the joint probability map of intensity and rotation invariant lbps; finally, it concatenates the probability maps of the three color channels and performs retrieval by comparing them by means of a lp metric [13]. the vk-algorithm computes the joint probability map as before, but without any color normalization, and implements a matching strategy that takes into account possible changes of colors due to illuminant variations, based on the von kries model [14] [15] [16]. in both these algorithms, the color and texture probability map can be weighted by the euclidean distance of each pixel from the image barycenter, in order to provide a global spatial description of the color distribution. the experiments carried out on the public realworld dataset [17] show that the proposed algorithms outperform the approaches based on color or lbps individually, and, in general, better results are obtained by using the weighted probability map. 2. local binary patterns: definition and computation let be a pixel of a gray level image and let be a circular neighbor of where denotes the radius of the neighbor and is the number of sampling points with coordinates defined by where are the coordinates of . due to the discrete nature of the data, when the coordinates of any sampling point do not fall at integer coordinates, the gray value is bilinearly interpolated. the lbp label at is defined as where indicates the gray value and is a thresholding function from to such that if and otherwise. the ordered sequence is said lbp code. any image rotation changes the order of the lbp code entries. invariance against rotations of an angle of (with an integer number) can be achieved by a circular bitwise cyclic shift (see fig. 1 for an example). experiments reported in [3] and [18] showed that 31 cultura e scienza del colore color culture and science | 07 | 2017 | 29 38 using color and local binary patterns for texture retrieval issn 2384-9568 the best texture description and classification is achieved by considering only a small subset of lbps, called uniform lbps. a lbp is said to be uniform if it contains at most two bitwise transitions (from 0 to 1 or vice-versa). the rotation invariant uniform lbp (denoted as lbpriu, where ri stands for rotation invariant and u for uniform) of a neighbor centered in is computed by the following equations: otherwise,with by the equations (2.1) and (2.1b), there are exactly lbprius: each uniform pattern is labeled by a number from 0 to , corresponding to the number of 1’s in its lbp code, while the non-uniform lpbs are grouped together under the label . fig. 2 shows the nine lbprius for = 1 and = 8. by definition, the s are invariant to monotonic changes and shifts of the gray level intensity of any image. in fact, for any real numbers a and b, with a>0 therefore, the lbps are robust to image noise modeled as an additive term, and to (2.1b) figure 1 example of lbp computation on a 3x3 neighborhood ( ). the central gray value is highlighted in red. the lbp codes and their corresponding labels with and without rotation normalization are shown in the blue and green boxes respectively. any changes of image intensity, caused for instance by shadows or by varying the distance of the camera from the light sources. as a consequence, the s of the red, green, and blue channels of a color image provide an (2.2) illuminant invariant description of the colored texture. in fact, the change of image colors due to an illuminant change is well approximated by the von kries diagonal map between the color responses captured under the varied lights [14], [16], i.e. where the s are real strictly positive numbers, called von kries coefficients, and is the intensity value of the -th color channel ( = 0, 1, 2, i.e. red, green, blue) of the rgb input image. since the values of each color channel under the von kries map satisfy the equation (2.2) for = 0, the corresponding lbps are illuminant invariant. similarly, also the lbps of the 1d chromaticity image defined by and otherwise, are insensitive to changes of illuminant. (2.3) (2.4) figure 2 the nine uniform lbps ù ( = 1, = 8). black and white circles represent the 0 and 1 8-bit values of the lbp operator. the number in blue denotes the unique code of each rotation invariant uniform lbp 3. visual description by color and lbps in many retrieval applications, the occurrences of the lbprius of an image are encoded into a histogram with bins [19]. the lbprius histogram has been proved to be an excellent feature for fast texture classification, also in comparison with other descriptors, as cooccurrence matrices, gabor filters, wavelets, or gaussian markov random fields [20] [21]. (2.1a) whileif 32 cultura e scienza del colore color culture and science | 07 | 2017 | 29 38 lecca m. issn 2384-9568 doi: 10.23738/ccsj.i72017.03 this work shows that the addition of some information about the distribution of the image color to the local description of the image texture provided by the lbprius histogram further increases the retrieval performance obtained by using the lbprius histograms only. while lbps are invariant to changes of illuminant, the color is strongly depends on the light: the two algorithms described next propose two different ways to use color by preserving illuminant invariance. 3.1. the gw-algorithm this algorithm is named gw-algorithm because it achieves invariance to changes of illuminant by normalizing the colors of any textured image by the well-known gray-world algorithm. the gray-world algorithm maps the color response at an image pixel on the triplet , with where is the mean value of the intensity of the -th channel. this means the mean rgb value of the new image obtained by the transformation in equation (3.1) is a gray color with intensity 128. this gray-world normalized image is invariant with respect to illuminant changes. in fact, let and be the rgb values at under two illuminants. according to the von kries model in equation (2.3) and to equation (3.1), the illuminant invariant feature used here integrates the color information encoded in the gray-world normalized image with the lbprius by computing for each chromatic channel of the joint probability of chromatic intensity and texture, i.e. where indicates the cardinality of the subsequent set, and vary respectively over and . the three histograms defined by equation (3.2) are then concatenated into a 2d probability map, that is encoded as a matrix (see fig. 3 for an example). the probability map can be also weighted by the euclidean distance of the pixels from the barycenter of the image support (i.e. from the barycenter of the set of pixels composing the image), in order to provide a global spatial description of the image color distribution. in particular, if is this barycenter, the weighted (3.2) version of equation (3.2) is with gray-world color normalization can be replaced with other techniques, that remove illuminant casts, as for instance [22] or [23]. the grayworld normalization has been chosen here among other color normalization approaches, due to its low computational charge. the histograms of two textured images, possibly related by an illuminant changes, are then matched by comparing their distance, that is a metric usually defined over a lebesgue integrable function space [13]. precisely, given two integrable (real-valued or complex) functions and defined over a domain , the distance between and is where . the equation of the distance can be easily re-formulated for discrete functions, by replacing the integral with a sum, so that the distance can be computed also in case of discrete data, as histograms or images. when p = 2, and and are encoded as vectors with finite dimension, the distance is the euclidean distance. 3.2. the vk-algorithm this algorithm is named vk-algorithm because it relies on the von kries model [14] [16]. the vk-algorithm describes the image appearance by the joint probability of color and texture, without any color normalization. the probability map is computed as before by splitting the input rgb images into its three channels and by computing the histograms of color and lbp as in the equations (3.2) or (3.3) where and are replaced by and , respectively. according to the von kries model, the probability maps and of each color channel of two images and of the same scene imaged under two different illuminants are stretched to each other by the von kries coefficients along the horizontal axis, i.e. for any (see fig. 3). given a query image and a reference , the vkalgorithm matches and as follows: a. the coefficients s are estimated by the method proposed in [15]: this minimizes the parametric earth mover distance between the rgb color histograms of and , or equivalently, (3.3) (3.1) 33 cultura e scienza del colore color culture and science | 07 | 2017 | 29 38 using color and local binary patterns for texture retrieval issn 2384-9568 between the horizontal projections of and . formally, let and be the histograms of the -th color channel of and respectively. by the von kries model thus, the method in [15] computes the set and estimates by a least square approach that finds the best line fitting the points of . the similarity between and is measured by the earth mover distance (emd) between and . this distance will be referred hereafter as parametric emd, because of its dependency on the coefficient (see [15] and [16] for more details); b. the probability is stretched accordingly, i.e. ; c. finally and are compared by a distance. if and are actually related by an illuminant change, then the distance between and is zero. 4. experiments the performance of the gwand vkretrieval algorithms has been measured on the public real-world image dataset outex_tc_00014 [17], that here will be indicates as outex for shortness. outex consists of 68 different classes of colored textures, each represented by 20 images and captured under three different lights (a 2856k incandescent cie a light denoted as “inca”, a figure 3 a texture from outex imaged under the three lights inca, tl84, horizon (see section 4 for more details) with their gray -world corrected images and the color & tex ture probabilities implemented by gwand vk-algorithms without weights and with ( = 1, = 8). 2300k horizon sunlight denoted as “horizon”, and a 4000k fluorescent light denoted as “tl84”). fig. 3 and fig. 4 show some examples. as already mentioned in section 1, given a query and a set of references, the image retrieval problem consists of finding the reference, which is the most similar to the query with respect to the used features. in our framework, the query is correctly retrieved if its class matches the class of the selected reference. the experiments have been carried out by setting as references the images captured under an illuminant ( = inca, horizon, tl84), and as query each image taken under another illuminant ( = inca, horizon, tl84), and . the retrieval accuracy has been measured by the average match percentile (amp) and by the recognition rate (rr). the amp is defined as where is the number of references, and indicates the position of the first correct response in the sorted list of the references output by the classifier, while rr is the percentage of texture images correctly classified (i.e. ). the performance of the gwand vkalgorithms has been compared with that output by other approaches that use exclusively texture or color information. in particular, the following descriptors have been considered: 1. the histograms of the lbprius computed over the rgb color channels; 2. the histograms of the lbprius computed over the 1d chromaticity image; 3.the histograms of the rgb colors of the gray-world normalized images; 34 cultura e scienza del colore color culture and science | 07 | 2017 | 29 38 lecca m. issn 2384-9568 doi: 10.23738/ccsj.i72017.03 4. the histograms of the rgb colors of the non normalized images. all the histograms listed before have been computed with and without euclidean distance weights. the algorithms using the features at points 1, 2, 3 perform image retrieval by a nearest neighbor classifier with the distance ( = 1, 2) as similarity measure. in addition, for the feature at point 1, the log-likelihood statistic used in [3] has been considered: where denotes a bin of the -th histograms and . the color histograms at point 4 have been matched by using the earth mover distance as proposed in [15], in order to ensure invariance against illuminant changes. fig. 5 shows an image, its gray-world normalization and its 1d chromaticity image, along with the descriptors at points 1, 2, 3, 4. the corresponding joint probability maps of color and textures used by gwand vk-algorithm are shown in fig. 6. tab. 1 summarizes the descriptors used in the experiments along with their acronyms. tab. 2 reports the mean values of amp and rr averaged over the number of database images and of the pairs . tab. 2 also shows the rounded up mean value of the rank . the value of controls the size of the neighbor of each pixel and thus the scale at which the texture is described. neighbors of different size capture different visual cues of the texture, and some of them may even provide poor or noised information. the value of is related to the robustness of the descriptors against in plane-rotation. the choice of the pair providing the best description in terms of retrieval performance is not addressed here, but the experiments have been carried out by considering two different values of : (1, 8) and (2, 16). all the retrieval algorithms achieve the best performance for = (2, 16), and with the descriptors weighted by the euclidean distance from the image barycenter. apart from the case of the lbprius histograms of the rgb color channels (point 1 in section 4), the retrieval performance does not change by using the distances or as similarity measure. therefore, for the other features, the results obtained with as retrieval distance are omitted in tab. 2. the worst results are obtained by using the lbprius histograms with , and the log-likelihood statistic as retrieval distance (amp = 0.8997 and rr = 10.61 %). the performance significantly increases for and . also the use of the lbprius histograms of the 1d chromaticity image does not provide good results, because the color information encoded in is too coarse. the gwand vkalgorithms provide the best performance. in particular, the best results are obtained by gw-algorithm with the weighted color and texture probability. in this case, amp = 0.9878 and on average the correct image is at the 18th place of the ranked list of references. by discarding the euclidean weights, rr (amp, resp.) is slightly higher (lower), than the rr (amp, resp.) achieved in the best case. however, these differences are negligible. the vk-algorithm outputs similar values of amp and , while rr is remarkably higher than that obtained by the gw-algorithm: the 47% against the 37%. this means that the number of images correctly classified (i.e. = 1) is higher for vk-algorithm than for the gw-algorithm, but the rank of the images not correctly classified is lower for vk-algorithm than for gw-algorithm. therefore, on average, the amp is more or less the same for both the algorithms. 5. conclusions according to previous studies, this work has shown empirically that the joint use of color and texture improves the performance of retrieval algorithms employing color or texture only. the retrieval algorithms presented here ensure invariance against variations of illuminant and in-plane rotation of the image. future work will include a multi-scale image analysis in order to achieve robustness against size changes, and the usage of the proposed algorithms for object detection and semantic image labeling. figure 4 some examples of colored textures from outex). 35 cultura e scienza del colore color culture and science | 07 | 2017 | 29 38 using color and local binary patterns for texture retrieval issn 2384-9568 acronym descriptor lbp (r, p) histograms of the lbprius with radius r and p sampling points computed over the three color channels. lbp (r, p), l2 histograms of the lbprius with radius r and p sampling points computed over the three color channels, weighted by the euclidean distance. lbpc(r, p) histograms of the lbprius with radius r and p sampling points computed on the 1d chromaticity image. lbpc(r, p), l2 histograms of the lbprius with radius r and p sampling points computed on the 1d chromaticity image, weighted by the euclidean distance. gw-colors histograms of the gray-world normalized color channels. gw-colors, l2 histograms of the gray-world normalized color channels, weighted by the euclidean distance. gw-colors + lbp(r, p) color & texture joint probability of gray-world normalized images [gw-algorithm] gw-colors + lbp(r, p), l2 color & texture joint probability of gray-world normalized images, weighted by the euclidean distance [gw-algorithm]. colors histograms of rgb color channels. colors, l2 histograms of rgb color channels, weighted by the euclidean distance. colors + lbp(r, p) joint probability of color and texture [vk-algorithm]. colors + lbp(r, p), l2 joint probability of color and texture, weighted by the euclidean distance [vk-algorithm]. table 1: acronyms of the retrieval algorithms. descriptor retrieval distance amp rr (%) mean rank [on 1360 img] lbp (1, 8) log-likelihood [3] 0.89971 10.613 137 lbp(2, 16) log-likelihood [3] 0.93845 18.125 85 lbp(1, 8) l2 0.90558 11.067 129 lbp(2, 16) l2 0.94323 18.787 78 lbp(1, 8) l1 0.93327 23.946 92 lbp(2, 16) l1 0.96827 36.078 44 lbp(1, 8), l2 l1 0.93492 23.836 89 lbp(2, 16), l2 l1 0.96968 35.343 42 lbpc(1, 8) l1 0.88932 11.618 151 lbpc(2, 16) l1 0.90535 18.027 130 lbpc(1, 8), l2 l1 0.89389 10.637 145 lbpc(2, 16), l2 l1 0.90871 16.544 125 gw-colors l1 0.97943 21.446 29 gw-colors, l2 l1 0.97939 21.336 29 gw-colors + lbp(1, 8) l1 0.98433 31.716 22 gw-colors + lbp(2, 16) l1 0.98766 37.378 18 gw-colors + lbp(1, 8), l2 l1 0.98416 31.017 23 gw-colors + lbp(2, 16), l2 l1 0.98779 36.863 18 colors parametric emd 0.95845 36.569 57 colors, l2 parametric emd 0.96118 36.703 54 colors + lbp(1, 8) parametric emd, l1 0.98256 42.451 25 colors + lbp(2, 16) parametric emd, l1 0.98633 47.745 19 colors + lbp(1, 8), l2 parametric emd, l1 0.98310 42.096 23 colors + lbp(2, 16), l2 parametric emd, l1 0.98685 47.708 18 table 2: retrieval results (see tab. 1 for the acronyms of used descriptors). in the last four descriptors, parametric emd has been used for computing the von kries coefficients and l1 to match the color corrected probability maps. funding this research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. conflict of interest the author declares no conflict of interest including financial, personal or other relationship with other people and organizations within three years of beginning the submitted work that could inappropriately influence, or be perceived to influence, this work 36 cultura e scienza del colore color culture and science | 07 | 2017 | 29 38 lecca m. issn 2384-9568 doi: 10.23738/ccsj.i72017.03 figure 5 an image, its gray-world normalization, its 1d chromaticity image and the color and texture descriptors listed in section 4, points 1, 2, 3, 4. the x-axis reports the intensity bins. 37 cultura e scienza del colore color culture and science | 07 | 2017 | 29 38 using color and local binary patterns for texture retrieval issn 2384-9568 bibliography [1] r. veltkamp, h. burkhardt and h.-p. kriegel, (eds), state-of-the-art in content-based image and video retrieval, 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[2] m. lecca, “color improves texture retreval,” in proc. of x colour conference, genova, italy, 2014. [3] m. pietikäinen, t. ojala and t. mäenpää, “multiresolution gray-scale and rotation invariant texture classification with local binary patterns,” ieee trans. on pattern analysis and machine intelligence, vol. 24, no. 7, 2002. [4] j. y. choi, k. plataniotis and y.-m. ro, “using colour local binary pattern features for face recognition,” in proc. of 17th ieee international conference on image processing, 2010. [5] g. anbarjafari, “face recognition using color local binary pattern from mutually independent color channels,” eurasip journal on image and video processing, vol. 1, no. 6, 2013. [6] s. banerji, a. verma and c. liu, “lbp and color descriptors for image classification,” in cross disciplinary biometric systems, springer, 2012, pp. 205-225. 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[21] r. porter and n. canagarajah, “robust rotationinvariant texture classification: wavelet, gabor filter and gmrf based schemes,” in vision, image and signal figure 6 color and texture descriptors (with and without euclidean weights) used by vkand gwalgorithms. these features refer to the image in fig. 5. the black bands visible in the probability maps of gw-algorithm are due to the discrete nature of the v isual data (the v alue in equation (3.1) is cast to an integer). 38 cultura e scienza del colore color culture and science | 07 | 2017 | 29 38 lecca m. issn 2384-9568 doi: 10.23738/ccsj.i72017.03 processing, iee proceedings, 1997. [22] e. provenzi, m. fierro, a. rizzi, l. de carli and d. marini, “random spray retinex: a new retinex implementation to investigate the local properties of the model,” ieee transactions on image processing, vol. 16, no. 1, pp. 162-171, 2007. [23] a. rizzi, c. gatta and d. marini, “from retinex to automatic color equalization: issues in developing a new algorithm for unsupervised color equalization,” j. electronic imaging, vol. 13, no. 1, pp. 75-84, 2004. cultura e scienza del colore color culture and science 21 cultura e scienza del colore color culture and science | 10 | 2018 issn 2384-9568 1hélène de clermontgallerande helene.declermontgallerande@ chanel-corp.com [corresponding author] 1nicolas rolland nicolas.rolland@chanel-corp. com 1patrick doucet patrick.doucet@chanel-corp. com 1julie deydier julie.deydier@chanel-corp.com 2anne varichon anne.varichon@culturecouleur. com 2barbara blin-barrois barbara@culturecouleur.com 1 chanel parfums beauté, 8 rue du cheval blanc cs40045, 93694 pantin cedex france 2 culture couleur sas, 600 bureaux du jas, 84000 roussillon france the changing colour of chanel’s lipstick ranges from 1960 to 2015 abstract we compiled the history of chanel’s range of lipsticks between 1960 and 2015 by studying the colour charts carefully kept in the company’s archives. the chosen colour space is ncs system as the representation of hue, blackness and chromaticness are easy to communicate to non-colour experts. the number of shades increased steadily between 1960 and 2005, rising from 12 shades in 1960 to 55 shades in 2005. from the colour point of view, there is a predominance of orangey tones. reds were always present. bluish reds were in constant decline compared with other shades: fewer in number, with a shorter life on the markets and more unstable in chanel’s offer. in terms of clarity, dark shades ranging to nearly black are in the great majority. as regards chromaticness, there is continuity in the saturated shades, especially the reds. lastly, the shades are fashioned with a high degree of subtlety as they are often very close to one another in the colorimetric space. at chanel, the delicacy of the shades is due to their colorimetric fashioning with all the subtlety typical of the brand keywords lipsticks, evolution, colour, colour charts, chanel, hue, ncs citation: de clermont-gallerande h., rolland n., doucet p., deydier j., varichon a. and blin-barrois b. (2018) ‘the changing colour of chanel’s lipstick ranges from 1960 to 2015’, cultura e scienza del colore color culture and science journal, 10, pp. 21-29, doi: 10.23738/ccsj.i102018.03 received 28 june 2017; revised 27 august 2018; accepted 27 august 2018 hélène de clermont-gallerande is make-up research laboratory manager in chanel. phd in organic chemistry, she has an experience of more than 25 years in make-up and colour formulation in cosmetic field and is inventor of more than 10 cosmetics patents. she is teaching cosmetic formulation at bordeaux’s university and published a collaborative book on sensorial cosmetic raw materials. she managed the color analysis for this study. nicolas rolland is colorist in chanel colour development laboratory for 5 years. previously, he worked in l’oreal, also as colorist. he has an expertise in color data management and achieved the measures of colour-charts for this study. after history of art studies, julie deydier worked in manufacture de sèvres (china), musée galliéra (paris city fashion museum), and joined chanel heritage department in 2003. she has been working more precisely on fragrance and beauty heritage for 11 years, developing a specialised knowkledge on luxury fragrance, makeup and skincare. particularly interested in colour and its use in beauty, she added her expertise on chanel cosmetics in this study. patrick doucet is the chanel fragrance and beauty heritage manager since 25 years and an expert about the gabrielle chanel and the brand chanel history. his vision is that the heritage must be a major contributor, in all its significant aspects, to the knowledge and the general development of the brand anne varichon, anthropologist in color materials, processes and thinking, phd in applied arts, expert in color charts. she publishes her researches in numerous publications (in particular “colors”). she teaches in universities and fine art schools and is in charge of museographical or research programs (notably with cnrs). she comanages culture couleur, a specialized agency in color-related phenomena, supporting companies and institutions on projects and cooperating in research or training activities. barbara blin-barrois, is an expert of systemic approaches and interdisciplinary methods, graduated in political sciences. she is cofoundator of ôkhra, a cultural colour cooperative in provence. she organized for 20 years cnrs scientific schools about colour materials and color cultural programs. barbara has developed specific pedagogical and mediation tools, favorizing multi-disciplinary stakeholders cooperation. she comanages culture couleur, a color research and learning agency. 22 cultura e scienza del colore color culture and science | 10 | 2018 | 21 29 de clermont-gallerande h., rolland n., doucet p., deydier j., varichon a. and blin-barrois b. issn 2384-9568 doi: 10.23738/ccsj.i102018.03 1. introduction the purpose of this study is to show how the colour of chanel lipsticks has changed over the past 55 years. since 1992 make-up products sold by the company have been kept, as have the colour charts, which represent all the available colour ranges in the form of a catalogue (varichon, 2011). these have been archived since 1930, which is why the decision was taken to work only on colour charts since the range of colours is complete, while in the oldest ranges some lipstick colours are missing. to reveal trends, the colour charts used are at 5-year intervals, unless the colour chart of the desired year is missing. the selected years for the study are 1960, 1963, 1970, 1972, 1980, 1985, 1990, 1995, 2000, 2005, 2010 and 2015. 2. materials and method the correspondence of the colours between a lipstick and its graphical representation in the colour chart was validated by measurement comparison using an x-rite vs450 contactless spectrophotometer in the ciel*a*b* colour space, in order not to damage the documents, some of which are old, and unique items in chanel’s heritage collections. there were few differences between the different colour charts and the lipsticks, meaning that a scientific study could be conducted without bias. it should be noted that the high quality of the paper used to make the colour charts of luxury companies and appropriate archiving conditions mean that the documents can be kept for a very long time, and therefore that colour measurements made several years after printing can be used. at chanel all the documents are stored in darkness, in rooms kept at a constant temperature of 19°c with 60 % relative humidity (hygrometry). they are handled only with gloves (colour chart from 1960 1963 1970 1972 1980 1985 1990 1995 2000 2005 2010. chanel own property). the colour samples of the colour charts are made through paint deposition by a serigraphy process. the ncs® system was chosen for the measurement of colour charts. the ncs® colour scan colorimeter was used to measure the 379 reference shades on the colour charts. duplicate ncs® references (or references with 3 or more identical references) were eliminated using the ncs® atlas (by eye, d65 light, x-rite box) except where no ncs® coordinate allowed a distinction to be made between colours (ncs color atlas, 3rd edition, 1996; ncs color album, 2nd edition, 1995). data was entered in the ncs navigator® application and displayed in the 3d space (ncscolor.com). hydrabase 1972 superhydrabase 1985 figure 1 comparison between colour charts and lipsticks . figure 2 the studied colour charts store in patrimony department from chanel. ranked from top to bottom: 1960, 1963, 1970, 1972, 1980, 1985, 1990, 1995, 2000, 2005, 2010, 2015. . 23 cultura e scienza del colore color culture and science | 10 | 2018 | 21 29 the changing colour of chanel’s lipstick ranges from 1960 to 2015 issn 2384-9568 each colour chart measured is characterized (hue, blackness, chromaticness). a comparative analysis between the different years is made (perec, 2003). this made it possible to determine changes in colour ranges over the years, forming a colour time line specific to chanel. 3. results the first period identified within the scope of the study was from 1960 to 1970. it is distinctive for the presence of a low blackness level and clear shades, high chromaticness or, the opposite, high desaturation of shades, the creation of 3 classical colours for chanel and the beginning of chromatic explorations (galante, 1972). from 1960, there were 12 lip colours, only light shades. saturated clear reds were already present. 12 additional pearlised shades appeared in 1963. these were all light and desaturated colours. this is explained by the launch of mica-titanium white pearls in 1959 by the merck™ company. the saturated reds are retained and scintillant is launched. this rouge-orangé (orangey-red) lipstick would be renamed sari doré in 1972 and still features in the rouge coco 2015 lipstick range. in 1970, golden and pale beiges predominated, reflecting the androgynous style first adopted by twiggy, but also a desire by the chanel company to be creative and innovative in the colours it offered (delay, 1973). in this same year, 2 other classic shades were created: téhéran, is still offered today after 52 years in the rouge coco range under the same name (mollard-desfour, 2001; 2002), and bombay that would last until 1990. interestingly, figure 3 the chosen colour space is ncs system. the 3d representation of hue, blackness and chromaticness are easy to communicate to noncolour experts figure 4 first period is from 1960 to 1970: low blackness level, creation of 3 classical shades for chanel and beginning of chromatic explorations. 24 cultura e scienza del colore color culture and science | 10 | 2018 | 21 29 de clermont-gallerande h., rolland n., doucet p., deydier j., varichon a. and blin-barrois b. issn 2384-9568 doi: 10.23738/ccsj.i102018.03 under its permanent name. the predominance of orangey reds was affirmed to the point that only one bluish-red was offered in the range of 1972. in 1980, the range offered 30 shades and saw the inclusion of an increased number of browns. these browns continued the changes begun in 1972 by reducing the differences between the colours. the shades were very closely packed in the colorimetric space, which created an increasingly subtle differentiation between them. the shades rooted in the brand’s dna appeared: printemps doré, now marie, prunelle now called cécile, pivoine which has become arthur, feu which is gabrielle and bois jackie kennedy’s visit to india in 1962 would influence the names given to chanel products, names such as bombay, sari doré, delhi, ispahan. the second period is from 1972 to 1980. it is characterized by the introduction of very dark shades, not only breaking away from medium light shades, but also establishing chanel’s colour basics for its lipsticks. the range was still in beige tones but had darkened towards browns. in 1980, fauve was the precursor of the red-blacks dear to chanel. few very bright colours except a few bright reds survived from earlier years. the sari doré colour, still present in chanel’s range today, made its appearance figure 5 second period is from 1972 to 1980: introduction of very dark shades and establishment of chanel’s colour basics for its lipsticks. figure 6 third period is from 1985 to 1995: presence of bluish reds and of very similar tones 25 cultura e scienza del colore color culture and science | 10 | 2018 | 21 29 the changing colour of chanel’s lipstick ranges from 1960 to 2015 issn 2384-9568 doré which is now misia. although the range is darker, a few saturated reds persist. despite the death of gabrielle chanel in 1971, chanel’s colour positioning continued to be rolled out: the predominance of orangey-reds, deep shades, the close similarity of subtly different shades in order to differentiate the range and the presence of saturated reds. a third period covers the years between 1985 and 1995. it is distinctive not only for the presence of bluish reds – a very temporary phase at chanel – but also for the constancy of an offer of darker and darker shades and very similar tones. in 1985, the colour range was very balanced: the range offered 30 shades, 10 of which were still orangey tones divided between light and dark shades although the very desaturated browns of 1980 had disappeared. bluish colours reappeared in light or dark shades and a group of highly saturated reds remained. in 1990, the colour chart presented 35 bright colours. the bluish shades were light or dark and sometimes highly saturated. the range of reds expanded to the point that the shades overlap in the colorimetric space. the orangey shades were more individualised and brighter than before. in 1995, chanel offered 42 shades of lipstick that explored dark tones. the very light shades vanished. only 6 light and with high chromaticness colours, including sari doré, maintained brightness. through an innovative blend of black and red, chanel’s vernis rouge noir was created for the autumnwinter 1994 catwalk show. a lipstick of the same colour was launched in 1996. during this decade, the similarity of the shades created translated into the existence of a number of duplicates: several lipsticks register on exactly the same ncs reference. this means that the shades are very similar as a group but look different when applied because of a more or less marked transparent effect or a pearly sheen. the fourth and last period is from 2000 to 2015. it is characterized by very deep shades, a marked low chromaticness as a result of nudging the center of the colorimetric space, particularly in 2000, an over-representation of orangey-reds and the similarity of the shades offered. in 2000, deep shades were offered with two very dark shades included in the range: brun sortilège and the iconic rouge noir. this time sari doré was still the only light and saturated colour. the number of shades and their close juxtaposition made it hard to discriminate to such levels of desaturation. in 2005, chanel offered 55 shades in order to meet the needs of worldwide business. this range was made lighter by the return of low chromaticness light shades, designed for the asian market, even though dark shades continued to predominate (varichon, 2011). in 2010, the range refocused on 37 shades but discarded all bluish shades with the exception of rose comète. the exclusion under cosmetics regulations of red 19 and red 9 in the 1990s, both natural fuchsia pink pigments, explains the difficulties of formulating bluish shades of lipstick. it retained a predominance of dark and desaturated shades going to almost black. high chromaticness shades, with the exception of sari doré, were discontinued. this decade showcased the “nearblacks” with measurements that fell very low on the clarity axis and very high desaturation levels (morand, 1976). the shades overlapped in the ncs colorimetric space, which shows that the different shades were worked to the limits of the ability to distinguish one from the other. in 2015, the range comprises 28 shades figure 7 fourth and last period is from 2000 to 2015: confirmation of very dark shades and low chromaticness, predominancy of orangey-red and very similar tones 26 cultura e scienza del colore color culture and science | 10 | 2018 | 21 29 de clermont-gallerande h., rolland n., doucet p., deydier j., varichon a. and blin-barrois b. issn 2384-9568 doi: 10.23738/ccsj.i102018.03 1960 1963 1970 1972 1980 1985 1990 1995 2000 2005 2010 2015 1960 1963 1970 1972 1980 1985 1990 1995 2000 2005 2010 2015 b ncs s ncs s 1 vison9 saumon 0570-y90r 11 étincelant 5 radieux 20 radieux 8 garance 14 étincelant 0580-y80r 56 téhéran 29 vison43 scintillant57 madalay 2 bois de rose59 colombo27 saumon 70 manille 3020-y80r 66 lhassa 2040-y50r 2 bois de rose64 bombay 56 téhéran10 jeunesse 0570-y80r 67 baalbeck 1515-y90r 68 mysore 2020-y90r 42 rose tropique 2030-y60r 72 sari 1060-y90r 5 été 15 orange 2075-y60r 18 acajou87 airelle81 atoll83 cristal de roche56 téhéran 88 miel24 bois doré 74 ceylan 74 ceylan 75 pivoine76 sari doré 78 mysore doré 3030-y80r 25 été doré64 bombay 82 lagon23 pourpre 76 sari doré 20 rouge podium 33 rouge fou rire 14 brun insolent#29 brasier d‘or56 téhéran67 bombay 2030-y90r 70 rouge coromandel 75 pivoine 52 cayenne 22 rouge star 36 lune rousse34 rouge de minuit 1085-y80r 76 sari doré 45 aventure65 éclair rouge22 rouge star56 téhéran 70 rouge coromandel 66 rouge de nuit 1580-y90r 60 rouge evasion 2070-y80r 42 rouge coralline 62 fatal 36 lune rousse14 brun insolent50 félin 39 ambre d‘or20 rouge podium 1085-y90r 76 sari doré 45 aventure 67 beige mythique22 rouge star56 téhéran 70 rouge coromandel 81 rouge péché 52 craquant 49 délice 99 ellipse 62 fatal 36 lune rousse 36 lune rousse russet moon 93 métal roux 14 brun insolent50 félin12 satellite 89 odyssée95 magnétique 39 ambre d‘or26 brun glacé 5020-y90r 97 rouge ténèbre 21 brun sortilège1 sorbet orange 1580-y80r 98 sensible 84 beige de chanel 6020-y90r 76 sari doré 69 tango 2060-y90r 56 téhéran72 jaïpur coral 2050-y80r 3 cashmere 77 crinoline 42 miami peach 25 energie 45 aventure80 osaka peach 67 beige mythique temptress 4020-y90r 90 pirate17 lys 1070-y90r 51 iris 2040-y90r 83 hanoï pink 4030-y90r 68 captif 2040-y80r 27 baby gold 3030-y90r 58 tokyo beige 4040-y60r 6 orient41 sahara beige 70 barcelona red #53 mirobolant swing79 rose paradise 28 pulsion50 félin 71 shantung 84 moiré 54 toscane bronze 7020-y80r 2 perlé 4030-y80r 6 égérie35 chintz 30 baroque 6030-y90r 56 téhéran 19 gabrielle 25 vendôme 3560-y90r 28 byzantin 36 lune rousse 4550-y90r 15 ruban rose 3050-y90r 4 cashmere 2060-y80r 27 talisman 5040-y90r 14 muse 4040-y90r 17 orchidée 21 rivoli8 la pausa 3060-y80r 76 sari doré 33 bois des iles 5030-y90r 29 ballet russe 7020-y90r 31 cambon 3060-y90r 10 camélia 4050-y90r 26 venise 6030-y80r 24 bel respiro 3560-y80r 32 sycomore 5040-y80r 1 beige félin 5030-y80r 3 secret 3050-y80r 34 satin 4040-y80r 410 catherine 1050-y80r 440 arthur 2070-y90r 404 julia 3040-y90r 402 adrienne 3040-y80r 400 louise 3030-y70r 414 sari doré 1070-y80r 406 antoinette 4550-y80r 416 coco 1080-y90r 408 jeanne 5540-y90r 418 misia 2570-y80r 444 gabrielle 2570-y90r 412 téhéran 2050-y90r 64 bombay 84 grenade76 sari doré 53 garance 75 pivoine 52 cayenne 19 feu 62 cuivre 62 cuivre 73 braise doré 45 piment88 miel35 rouge de chanel 25 été doré7 gorge de pigeon56 téhéran 34 sable roux51 brun flamboyant39 rose flamboyant 32 sable rose 70 rouge coromandel76 sari doré 68 aurore53 garance 75 pivoine 52 cayenne 54 rouge impatient 9 brun marine56 téhéran 3560-y70r 0570-y90r 0580-y80r 3020-y80r2040-y50r0570-y80r 1515-y90r 2020-y90r 2030-y60r1060-y90r 2075-y60r 3030-y80r2030-y90r1085-y80r 1580-y90r 2070-y80r1085-y90r 5020-y90r1580-y80r 6020-y90r2060-y90r 2050-y80r 4020-y90r1070-y90r 2040-y90r 4030-y90r2040-y80r 3030-y90r 4040-y60r 7020-y80r4030-y80r 6030-y90r3560-y90r 4550-y90r3050-y90r2060-y80r 5040-y90r4040-y90r3060-y80r 5030-y90r 7020-y90r3060-y90r 4050-y90r 6030-y80r3560-y80r 5040-y80r5030-y80r3050-y80r 4040-y80r1050-y80r 2070-y90r 3040-y90r3040-y80r3030-y70r1070-y80r 4550-y80r1080-y90r 5540-y90r2570-y80r 2570-y90r2050-y90r 3560-y70r 67 bombay distinctive for their variety and brightness. colours are deployed in the colorimetric space, reconnecting with the individualised tones that had been eliminated since the 1970s. the range has rediscovered a balance not only between orangey, red and bluish shades, but between light and dark shades too. 4. discussion hue: if one has to identify the signature lipstick shades specific to chanel, this is what appears to emerge from this study: predominance and constancy of the orangey colours. these are present as beiges and browns, but also as vivid tones. the most emblematic are sari doré, reference ncs 2070y90r which has been present since 1972 with 10 occurrences and téhéran under ncs reference 2050-y90r present since 1963, or 52 years and 11 occurrences at the time of the study. the saturation of the reds. there are fewer of figure 8 colour time line for the orangey red lipsticks. the vertical axis represents the years studied. the horizontal axis represents the ncs references ranked from the lower to the higher blackness. each coloured rectangle is the representation of a lipstick mentioned on a colour chart. 1960 1963 1970 1972 1980 1985 1990 1995 2000 2005 2010 2015 1960 1963 1970 1972 1980 1985 1990 1995 2000 2005 2010 2015 b ncs s ncs s 1 vison9 saumon 0570-y90r 11 étincelant 5 radieux 20 radieux 8 garance 14 étincelant 0580-y80r 56 téhéran 29 vison43 scintillant57 madalay 2 bois de rose59 colombo27 saumon 70 manille 3020-y80r 66 lhassa 2040-y50r 2 bois de rose64 bombay 56 téhéran10 jeunesse 0570-y80r 67 baalbeck 1515-y90r 68 mysore 2020-y90r 42 rose tropique 2030-y60r 72 sari 1060-y90r 5 été 15 orange 2075-y60r 18 acajou87 airelle81 atoll83 cristal de roche56 téhéran 88 miel24 bois doré 74 ceylan 74 ceylan 75 pivoine76 sari doré 78 mysore doré 3030-y80r 25 été doré64 bombay 82 lagon23 pourpre 76 sari doré 20 rouge podium 33 rouge fou rire 14 brun insolent#29 brasier d‘or56 téhéran67 bombay 2030-y90r 70 rouge coromandel 75 pivoine 52 cayenne 22 rouge star 36 lune rousse34 rouge de minuit 1085-y80r 76 sari doré 45 aventure65 éclair rouge22 rouge star56 téhéran 70 rouge coromandel 66 rouge de nuit 1580-y90r 60 rouge evasion 2070-y80r 42 rouge coralline 62 fatal 36 lune rousse14 brun insolent50 félin 39 ambre d‘or20 rouge podium 1085-y90r 76 sari doré 45 aventure 67 beige mythique22 rouge star56 téhéran 70 rouge coromandel 81 rouge péché 52 craquant 49 délice 99 ellipse 62 fatal 36 lune rousse 36 lune rousse russet moon 93 métal roux 14 brun insolent50 félin12 satellite 89 odyssée95 magnétique 39 ambre d‘or26 brun glacé 5020-y90r 97 rouge ténèbre 21 brun sortilège1 sorbet orange 1580-y80r 98 sensible 84 beige de chanel 6020-y90r 76 sari doré 69 tango 2060-y90r 56 téhéran72 jaïpur coral 2050-y80r 3 cashmere 77 crinoline 42 miami peach 25 energie 45 aventure80 osaka peach 67 beige mythique temptress 4020-y90r 90 pirate17 lys 1070-y90r 51 iris 2040-y90r 83 hanoï pink 4030-y90r 68 captif 2040-y80r 27 baby gold 3030-y90r 58 tokyo beige 4040-y60r 6 orient41 sahara beige 70 barcelona red #53 mirobolant swing79 rose paradise 28 pulsion50 félin 71 shantung 84 moiré 54 toscane bronze 7020-y80r 2 perlé 4030-y80r 6 égérie35 chintz 30 baroque 6030-y90r 56 téhéran 19 gabrielle 25 vendôme 3560-y90r 28 byzantin 36 lune rousse 4550-y90r 15 ruban rose 3050-y90r 4 cashmere 2060-y80r 27 talisman 5040-y90r 14 muse 4040-y90r 17 orchidée 21 rivoli8 la pausa 3060-y80r 76 sari doré 33 bois des iles 5030-y90r 29 ballet russe 7020-y90r 31 cambon 3060-y90r 10 camélia 4050-y90r 26 venise 6030-y80r 24 bel respiro 3560-y80r 32 sycomore 5040-y80r 1 beige félin 5030-y80r 3 secret 3050-y80r 34 satin 4040-y80r 410 catherine 1050-y80r 440 arthur 2070-y90r 404 julia 3040-y90r 402 adrienne 3040-y80r 400 louise 3030-y70r 414 sari doré 1070-y80r 406 antoinette 4550-y80r 416 coco 1080-y90r 408 jeanne 5540-y90r 418 misia 2570-y80r 444 gabrielle 2570-y90r 412 téhéran 2050-y90r 64 bombay 84 grenade76 sari doré 53 garance 75 pivoine 52 cayenne 19 feu 62 cuivre 62 cuivre 73 braise doré 45 piment88 miel35 rouge de chanel 25 été doré7 gorge de pigeon56 téhéran 34 sable roux51 brun flamboyant39 rose flamboyant 32 sable rose 70 rouge coromandel76 sari doré 68 aurore53 garance 75 pivoine 52 cayenne 54 rouge impatient 9 brun marine56 téhéran 3560-y70r 0570-y90r 0580-y80r 3020-y80r2040-y50r0570-y80r 1515-y90r 2020-y90r 2030-y60r1060-y90r 2075-y60r 3030-y80r2030-y90r1085-y80r 1580-y90r 2070-y80r1085-y90r 5020-y90r1580-y80r 6020-y90r2060-y90r 2050-y80r 4020-y90r1070-y90r 2040-y90r 4030-y90r2040-y80r 3030-y90r 4040-y60r 7020-y80r4030-y80r 6030-y90r3560-y90r 4550-y90r3050-y90r2060-y80r 5040-y90r4040-y90r3060-y80r 5030-y90r 7020-y90r3060-y90r 4050-y90r 6030-y80r3560-y80r 5040-y80r5030-y80r3050-y80r 4040-y80r1050-y80r 2070-y90r 3040-y90r3040-y80r3030-y70r1070-y80r 4550-y80r1080-y90r 5540-y90r2570-y80r 2570-y90r2050-y90r 3560-y70r 67 bombay 27 cultura e scienza del colore color culture and science | 10 | 2018 | 21 29 the changing colour of chanel’s lipstick ranges from 1960 to 2015 issn 2384-9568 these than there are orangey colours, but their saturation makes them stand out. reds such as rouge noir, with 3 occurrences, reference ncs 7020-r, are all intense, and have become iconic. one can also mention paris, reference ncs 2570-r, and marie, reference ncs 3560r, both repeated in 8 occurrences. the reds have exceptional longevity at chanel: a red shade remains on the market for 19 years on average. so there is little novelty but real fidelity over time, which shows that the true reds suit chanel’s customers. the discretion of blue tones. no signature specific to chanel emerges. only one shade representative of this tonality appears twice in the ranges: bruyère in 1972, as well as rose comète in 2010. amongst the longest lasting blues, reference ncs 2060-r10b is repeated on 6 occasions and reference 2070-r10b is repeated on 8 occasions. 1960 1963 1970 1972 1980 1985 1990 1995 2000 2005 2010 2015 1960 1963 1970 1972 1980 1985 1990 1995 2000 2005 2010 2015 ncs s ncs s 1040-r20b 1050-r10b 6020-r10b3040-r10b1040-r10b 2040-r20b 2060-r10b 2060-r20b 2065-r20b1060-r20b 4050-r20b 7020-r20b2070-r10b1575-r10b 2050-r20b 4030-r20b2040-r10b 3040-r 2050-r10b 4050-r 3060-r10b 1070-r 1070-r20b 3050-r10b 1580-r 3040-r20b 2040-r 6030-r1080-r 5040-r1060-r 3020-r 4020-r10b 4030-r 2060-r 3060-r 7020-r0550-r 2070-r 5030-r0565-r 3560-r 3050-r2050-r 1060-r10b 4050-r10b 6030-r20b1070-r10b 2570-r 4040-r 5020-r20b 5040-r10b3060-r20b 1040-r20b 1050-r10b 6020-r10b3040-r10b1040-r10b 2040-r20b 2060-r10b 2060-r20b 2065-r20b1060-r20b 4050-r20b 7020-r20b2070-r10b1575-r10b 2050-r20b 4030-r20b2040-r10b 2050-r10b 3060-r10b1070-r20b 3050-r10b3040-r20b 4020-r10b1060-r10b 4050-r10b 6030-r20b1070-r10b 5020-r20b 5040-r10b3060-r20b 3030-r0560-r 3040-r 4050-r1070-r 1580-r 2040-r 6030-r1080-r 5040-r1060-r 3020-r 4030-r 2060-r 3060-r 7020-r0550-r 2070-r 5030-r0565-r 3560-r 3050-r2050-r 2570-r 4040-r3030-r0560-r 10 midi 7 rue cambon 30 primerose 42 rose tropique 13 midi 60 delhi 61 karachi31 rue cambon12 éclatant 60 delhi13 midi4 printemps 26 printemps doré77 manille doré 89 prunelle16 sangria13 midi 38 rouge flamboyant 38 rouge flamboyant 38 rouge flamboyant 27 praline 99 rose cuivré 8 griotte 12 rouge dragon 23 rouge orage37 rose caprice 32 rouge imprévu 2 rouge marquise 38 rouge flamboyant 78 provocation 2 rouge marquise 64 écrin rouge44 rose frêle 12 rouge dragon 47 escapade35 accent 3 or rouge 72 rouge imaginaire 23 rouge orage 23 rouge orage 92 rose passion 40 pourpre 20 sidéral59 canicule33 polaire 82 topaze 47 escapade 40 pourpre 88 calypso86 boréal 53 mirobolant 18 rouge noir 47 escapade désert rose 23 rouge orage rosestone94 aurora 60 new york red2 india762 image rose 48 english rose 65 fire78 shanghaï red 49 venice violine64 rose baby 18 rouge noir vamp 18 rouge noir23 rouge orage22 paris 11 légende37 rose dentelle 13 gardénia 5 mademoiselle16 taffetas rose 9 organdi rose 428 légende432 cécile 434 mademoiselle442 dimitri 446 étienne430 marie 438 suzanne 6 éclatant 92 rose passion 77 manille doré 27 praline 8 griotte13 midi 02 rouge en diable 77 rouge comédie 92 rose passion 01 terre cuite 1 vénitien 99 rose cuivré 27 praline rose 83 brun coromandel 8 griotte 89 ouragan rouge 26 rouge magique 37 rose caprice 87 flamme rose 98 rose brûlant 12 flamme2 rose aurore 3 rose mousseline 4 rose tendre 55 ispahan22 rose aurore 22 rose aurore 9 rose mousseline1 rose tendre 62 ankara 46 fuchsia 58 bénarès63 lahore19 flamme 19 flamme 73 taloda 17 bruyère 30 rose fission 19 rouge n°1948 rose de chanel 86 flamme bleue 90 ouragan bleu91 rose éclat 91 rose éclat 16 rose escale 6 rouge satin 13 rose fou 57 bengale 31 faille rose68 aurore 41 précieux #17 intensité rose 6 rouge satin48 rose de chanel 19 rouge n°19 55 envoûtant 79 insolite 91 rose éclat16 rose escale 13 rose fou 30 rose frisson 31 faille rose 46 rose d‘or61 rose de glace 41 précieux17 intensité rose #9 rouge n°1955 evoûtant34 sirocco 37 morocco96 rouge argent 57 pimpant 61 rose de glace 10 malice 73 violette 29 fuschine55 envoûtant berry11 sirène7 bengale 19 rouge n°1957 pimpant66 vanity 40 pink ballerina13 rosalilas 32 vibrant4 azaléa 34 sirocco44 paris pink 20 rose comète 450 ina420 vera 426 roussy 452 émilienne 454 jean422 olga 456 erik424 édith 448 élise 43 carmin61 fuchsia 7 rose marine 55 fauve 48 rose de chanel 57 bengale 86 flamme bleue59 bruyère 71 laque rouge figure 9 colour time line for the blue and red lipsticks. the vertical axis represents the years studied. the horizontal axis represents the ncs references ranked from the lower to the higher blackness. each coloured rectangle is the representation of a lipstick mentioned on a colour chart 1960 1963 1970 1972 1980 1985 1990 1995 2000 2005 2010 2015 1960 1963 1970 1972 1980 1985 1990 1995 2000 2005 2010 2015 ncs s ncs s 1040-r20b 1050-r10b 6020-r10b3040-r10b1040-r10b 2040-r20b 2060-r10b 2060-r20b 2065-r20b1060-r20b 4050-r20b 7020-r20b2070-r10b1575-r10b 2050-r20b 4030-r20b2040-r10b 3040-r 2050-r10b 4050-r 3060-r10b 1070-r 1070-r20b 3050-r10b 1580-r 3040-r20b 2040-r 6030-r1080-r 5040-r1060-r 3020-r 4020-r10b 4030-r 2060-r 3060-r 7020-r0550-r 2070-r 5030-r0565-r 3560-r 3050-r2050-r 1060-r10b 4050-r10b 6030-r20b1070-r10b 2570-r 4040-r 5020-r20b 5040-r10b3060-r20b 1040-r20b 1050-r10b 6020-r10b3040-r10b1040-r10b 2040-r20b 2060-r10b 2060-r20b 2065-r20b1060-r20b 4050-r20b 7020-r20b2070-r10b1575-r10b 2050-r20b 4030-r20b2040-r10b 2050-r10b 3060-r10b1070-r20b 3050-r10b3040-r20b 4020-r10b1060-r10b 4050-r10b 6030-r20b1070-r10b 5020-r20b 5040-r10b3060-r20b 3030-r0560-r 3040-r 4050-r1070-r 1580-r 2040-r 6030-r1080-r 5040-r1060-r 3020-r 4030-r 2060-r 3060-r 7020-r0550-r 2070-r 5030-r0565-r 3560-r 3050-r2050-r 2570-r 4040-r3030-r0560-r 10 midi 7 rue cambon 30 primerose 42 rose tropique 13 midi 60 delhi 61 karachi31 rue cambon12 éclatant 60 delhi13 midi4 printemps 26 printemps doré77 manille doré 89 prunelle16 sangria13 midi 38 rouge flamboyant 38 rouge flamboyant 38 rouge flamboyant 27 praline 99 rose cuivré 8 griotte 12 rouge dragon 23 rouge orage37 rose caprice 32 rouge imprévu 2 rouge marquise 38 rouge flamboyant 78 provocation 2 rouge marquise 64 écrin rouge44 rose frêle 12 rouge dragon 47 escapade35 accent 3 or rouge 72 rouge imaginaire 23 rouge orage 23 rouge orage 92 rose passion 40 pourpre 20 sidéral59 canicule33 polaire 82 topaze 47 escapade 40 pourpre 88 calypso86 boréal 53 mirobolant 18 rouge noir 47 escapade désert rose 23 rouge orage rosestone94 aurora 60 new york red2 india762 image rose 48 english rose 65 fire78 shanghaï red 49 venice violine64 rose baby 18 rouge noir vamp 18 rouge noir23 rouge orage22 paris 11 légende37 rose dentelle 13 gardénia 5 mademoiselle16 taffetas rose 9 organdi rose 428 légende432 cécile 434 mademoiselle442 dimitri 446 étienne430 marie 438 suzanne 6 éclatant 92 rose passion 77 manille doré 27 praline 8 griotte13 midi 02 rouge en diable 77 rouge comédie 92 rose passion 01 terre cuite 1 vénitien 99 rose cuivré 27 praline rose 83 brun coromandel 8 griotte 89 ouragan rouge 26 rouge magique 37 rose caprice 87 flamme rose 98 rose brûlant 12 flamme2 rose aurore 3 rose mousseline 4 rose tendre 55 ispahan22 rose aurore 22 rose aurore 9 rose mousseline1 rose tendre 62 ankara 46 fuchsia 58 bénarès63 lahore19 flamme 19 flamme 73 taloda 17 bruyère 30 rose fission 19 rouge n°1948 rose de chanel 86 flamme bleue 90 ouragan bleu91 rose éclat 91 rose éclat 16 rose escale 6 rouge satin 13 rose fou 57 bengale 31 faille rose68 aurore 41 précieux #17 intensité rose 6 rouge satin48 rose de chanel 19 rouge n°19 55 envoûtant 79 insolite 91 rose éclat16 rose escale 13 rose fou 30 rose frisson 31 faille rose 46 rose d‘or61 rose de glace 41 précieux17 intensité rose #9 rouge n°1955 evoûtant34 sirocco 37 morocco96 rouge argent 57 pimpant 61 rose de glace 10 malice 73 violette 29 fuschine55 envoûtant berry11 sirène7 bengale 19 rouge n°1957 pimpant66 vanity 40 pink ballerina13 rosalilas 32 vibrant4 azaléa 34 sirocco44 paris pink 20 rose comète 450 ina420 vera 426 roussy 452 émilienne 454 jean422 olga 456 erik424 édith 448 élise 43 carmin61 fuchsia 7 rose marine 55 fauve 48 rose de chanel 57 bengale 86 flamme bleue59 bruyère 71 laque rouge 28 cultura e scienza del colore color culture and science | 10 | 2018 | 21 29 de clermont-gallerande h., rolland n., doucet p., deydier j., varichon a. and blin-barrois b. issn 2384-9568 doi: 10.23738/ccsj.i102018.03 blackness: dark colours are in the majority, and include near-blacks. except for the years 1960, 1963 and 1970, when the ranges only had light colours, from 1972 most colours have been dark. dark does not mean dull: rouge noir is dark and very vivid. the years 1995, 2000, 2005 and 2010, in particular, developed dark tonalities. since 2000 the dark colours have been very close to black in the chromatic space. there is only one colour with this degree of black in the 2015 range, but more than 3/4 of the range was in this category at the apogee of the “near-blacks”. chromaticness: vividness is confirmed unambiguously. all the ranges contain many saturated colours, whichever year is considered, and whatever the brightness or tonality of the lipsticks. the 2 most restrained ranges are 2005 and 2010, years marked by dark colours. conversely, 1995, which was also very dark, was full of contrasts, as it is one of the most vivid ranges. the 3 highest chromaticness ranges are 1980, 1990, and 1995, within which the most intense colours are garance, rouge de minuit and rouge podium, respectively. from 1960 chanel sold 12 lipsticks, quite a broad choice compared to other cosmetic brands at the time. the colour offer exploded in the following years, reaching 55 shades in 2005. chanel has always explored chromatic areas, first by offering low chromaticness beiges from 1970 the near-blacks from 1980. bright reds have been a constant in the brand’s offer. finally, 3 documents that summarize all hues present in the ranges were created. they are called colour time lines. one is dedicated to orangey red lipsticks and the header is yellow. the second one is dedicated to blue lipsticks and the third to red lipsticks. in this publication, blue and red lipsticks all come together. the band that underlines the colour time line is blue for the bluish lipsticks and red for the red ones. if all the ranges under study are considered, it can be seen that colour differences between the different lipsticks have reduced since 1980. the colours have become closer to one another in the colorimetric space, making it ever more difficult to distinguish one colour from another. the number of colours and their close juxtaposition sometimes makes it difficult to discriminate between them. 5. conclusions through the analysis of the in-house colour charts, the history of chanel lipstick colour from 1960 to 2015 was written. the main lines that chanel is drawing that are its own characteristics are the one following: for the hue, there is a predominance of orangey-red tones, a saturation of the reds and a shyness of blue tones. for the blackness, there is a huge majority of dark colours, including near-blacks. for the chromaticness, there is a constancy of saturated colours. there is a huge increase of the numbers of shades proposed to the customers starting from 12 shades in 1960 and growing up to 55 shades in 2005. and as already mentioned, the colours are very close one from each other in the colorimetric space and can be near similar excepted a pearlescent or satiny effect. funding this research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sector. conflict of interest the authors declare that there is no conflict of interest with other people or organizations. bibliography colour chart from 1980. chanel own property colour chart from 1985. chanel own property colour chart from 1990. chanel own property colour chart from 1995. chanel own property colour chart from 2000. chanel own property colour chart from 2005. chanel own property colour chart from 2010. chanel own property colour chart from 2015. chanel own property delay c. (1983) chanel solitaire. paris: éd. gallimard, p. 192 galante p. (1972) les années chanel. paris: éd. parismatch/mercure de france, p.50 mollard-desfour a. (2001) dictionnaire des mots et expressions de couleur : le rouge, editions cnrs mollard -desfour a. (2002), dictionnaire des mots et expressions de couleur : le rose, editions cnrs morand p. (1976) l’allure de chanel. paris: éd. hermann, rééd. 1996, ill. karl lagerfeld, pp 55-57. ncs color atlas, 3rd edition, 1996 ncs color album, 2nd edition, 1995 ncscolor.com perec g. (2003) penser/classer, editions du seuil varichon a. (2011) « noir et blanc dans les nuanciers : couple fertile ou célibataires endurcis? », proceedings of spring school from c2rmf upmc mnhn cf, la 29 cultura e scienza del colore color culture and science | 10 | 2018 | 21 29 the changing colour of chanel’s lipstick ranges from 1960 to 2015 issn 2384-9568 couleur des matériaux, roussillon, mars, pp 115-118 varichon a. (2011) couleur et nuancier, territoires et fonctions, analyse poïétique de l’échantillonnage de la couleur par les manufactures, l’industrie et le commerce (mi-xixème à nos jours), thèse de doctorat en arts appliqués nnt: 2011tou20129 cultura e scienza del colore color culture and science 59 cultura e scienza del colore color culture and science | 07 | 2017 issn 2384-9568 1shogo nishi s-nishi@osakac.ac.jp 1akira kimachi kima@osakac.ac.jp 1motonori doi doi@osakac.ac.jp 2shoji tominaga shojitominaga12@gmail.com 1faculty of information and communication engineering, osaka electro-communication university 2graduate school of advanced integration science, chiba university image registration for a multispectral imaging system using interference filters and application to digital archiving of art paintings abstract the present paper proposes a calibration method of a multispectral imaging system using interference filters. a multispectral imaging with interference filter is effective to acquire the inherent information of an object surface. however, in the imaging system using interference filters, the problem of misregistration is caused by longitudinal aberration or transverse aberration, where image position is slightly different between each captured image with the interference filters. we present a calibration method for correcting the observed images. the captured images are transformed into frequency domain, where the phase correlation between the fourier-transformed images for different channels is maximized so as to compensate the misregistration. as a practical use, we describe the application to digital archive of paintings based the present imaging system. the surface properties such as surface-spectral reflectance and surface normal are estimated using the multichannel images. keywords interference filter, spectral imaging, misregistration, calibration, phase-only correlation, digital archiving. citation: nishi s., kimachi a., doi m., tominaga s. (2017) ‘image registration for a multispectral imaging system using interference filters and application to digital archiving of art paintings’, cultura e scienza del colore color culture and science journal, 06, pp. 59-68, doi: 10.23738/ccsj. i72017.05 received 31 july 2016; revised 30 may 2017; accepted 31 may 2017 shogo nishi, is an associate professor in the department of engineering informatics at osaka electro-communication university, osaka, japan. he received his b.e. (1998) and ph.d. (2003) in information engineering from kagoshima university. his current research interests include spectral imaging, color image analysis, reflection modeling, and color reproduction. he is a member of is&t and osa. akira kimachi is a professor in the department of engineering informatics at osaka electro-communication university, osaka, japan. he received his b.s. (1993) and ph.d. (1999) in mathematical engineering and information physics from the university of tokyo. his current research interests include optical measurement, image sensing and computer vision. he is a member of osa, spie and ieee. motonori doi is an associate professor in the department of telecommunication and computer networks at osaka electro-communication university, osaka, japan. he received his b.s. in control engineering from osaka university (1993) and his ph.d. in information engineering from nara advanced institute of science and technology (naist) (1998). his current research interests include color/spectral image analysis. he is a member of is&t and ieee. shoji tominaga received the ph.d. degree in electrical engineering from osaka university, japan in 1975. he was a professor at graduate school of advanced integration science, chiba university, and is now a specially appointed researcher. his research interests include digital color imaging, multispectral imaging, and material appearance. he is a fellow of ieee, is&t, spie, osa, and ieice. 60 cultura e scienza del colore color culture and science | 07 | 2017 | 59 68 nishi s., kimachi a., doi m., tominaga s. issn 2384-9568 doi: 10.23738/ccsj.i72017.05 1. introduction in recent years, it has attracted attention to a digital archive for preserving the historical and artistic heritage in the digital image information. in the digital archive of art paintings, the key technology is the image acquisition by a digital camera and the image reproduction to render the realistic appearance on a display device. there were many proposals for the fundamental technology. for instance, miyake et al. [1] developed a multiband camera system to record the reflectance spectra of paintings. the system consisted of a monochrome charge-coupled device (ccd) camera and a rotating filter wheel composed of five color filters. tominaga et al. [2] proposed a photometric technique with a six-band multispectral camera for estimating the spectral reflectances, surface normals and 3-d light reflection properties of oil paintings. using this method, these authors reproduced the appearance of paintings under arbitrary conditions of viewpoint and illumination. this approach is called the viewpoint and illumination-independent digital archiving. moreover, tominaga et al. [3] proposed a digital archiving method using a multiband scanner as a multiband spectral imaging system for estimating the painting surfaces. to digitally preserve paintings, information on the painting’s surface must be precisely recorded. the technology of multispectral imaging is quite effective. since a multispectral imaging system has high wavelength resolution compared with color cameras, colorimetric accuracy in the acquired image is certainly improved. we should note that the multispectral system is useful not only for colorimetry, but also for estimation of surface spectral reflectances and surface normal vectors (see [2]-[3]). the typical multiband systems are constructed by (1) using one or two additional color filters to a trichromatic digital camera [4], (2) combining a monochrome camera and color filters with different spectral bands [5], (3) using narrow band interference filters [6], or (4) using a liquidcrystal tunable (lct) filter [7]. our present system is a multispectral imaging system that uses interference filters [8]. this system has the advantage of accuracy and stability in spectral estimations, because the filtration of the spectral system is narrow band and the side lobe component included in the camera output signal is reduced. the system also has the advantage of facilitating the design of a desired spectral measurement system, because a number of relatively low-cost interference filters with various transmission band characteristics are available. however, one limitation of the system is image misregistration, which is caused by longitudinal aberrations or transverse aberrations. a number of calibration techniques for the misregistration in spectral images were proposed so far. mansouri et al. [9] improved the misregistration optically caused by longitudinal aberration by performing the blur modeling and image restoration. brauers et al. [10] calibrated misregistrations caused by transverse aberration via modeling based on affine transformation. in our measurement system, the misregistration of the acquired images is non-uniform in the image, and the amount and direction of misregistration vary for each filter. therefore the previous methods are not available for the present misregistration problem. because this chromatic aberration is a fatal defect in the digital archive of painting, precise registration is required. in this paper, we propose a solution method for calibrating the misregistration caused by using the interference filters. the spectral images acquired from a painting are divided into several areas to correct for non-uniform misregistration. the divided images are then transformed into frequency domain, where the phase correlation between the fourier-transformed images for different channels is maximized so as to compensate the misregistration. the alignment is performed between the divided spectral images. since this method does not require a calibration chart, calibration can be performed directly without depending on an object to be calibrated. as a practical use, we describe the application to digital archive of paintings based the present imaging system. 2. multispectral imaging system 2.1. composition the multispectral imaging system is shown in fig. 1(a). our multispectral imaging system is composed of a monochrome ccd camera (toshiba teli, cs3920), a c mount lens (tamron, 20ha), an automatic filter changer (asahi spectra, fc8-25a), and eight interference filters (asahi spectra). the camera has a resolution of 1636 × 1236 and records with a dynamic range of 10-bit quantization. center transmission wavelengths of the interference filters are 420, 450, 490, 530, 570, 610, 650, and 670 nm, and the full width at half maximum filtration is approximately 10 nm. these interference filters are mounted on the rotary wheel of the filter changer, and the selected filter is placed in front of the camera lens. multispectral imaging is achieved by capturing images while rotating the wheel. fig. 1 (b) shows the total spectral sensitivity multiplied by the spectral transmittance of the eight filters and the spectral sensitivity of the ccd sensor. the ccd outputs 61 cultura e scienza del colore color culture and science | 07 | 2017 | 59 68 image registration for a multispectral imaging system using interference filters and application to digital archiving of art paintings issn 2384-9568 are band-pass signals in the visible wavelength range, and they are finally integrated to analyze the surface reflection properties of an object. 2.2. characteristics of the interference filter in an imaging system an interference filter is formed by depositing a dielectric multilayer film on the substrate surface; therefore, a specific wavelength band can be selectively acquired from the spectral distribution of incident light. wavelength selection is determined by the same principle adopted by the fabry-perot interferometer. an image acquisition system using interference filters has the advantage of analyzing the target at a desired wavelength band. however, incorporating an interference filter in the imaging optical system causes focal shifts and misregistrations. focus adjustment is conducted manually for each filter. we also confirmed that varying the magnification of the lens can be ignored. therefore, our goal is to calibrate the misregistration in spectral images. in our multiband imaging system, the interference filters are mounted on a filter changer. consequently, the main factor underlying the misregistrations may be that the interference filters are not parallel to the sensor surface. because an interference filter is influenced by temperature and humidity, the spectral transmission characteristic may change for each acquired image. moreover, a transformation matrix cannot be easily prepared for calibration by using a particular calibration subject. therefore, the misregistration must be calibrated for each acquired image. 3. image registration for spectral images image registration is one of the topics in the field of image processing, and various registration methods have been proposed. although luminance is an important image feature that is utilized in many registration methods, this feature is not available for registration because the luminance of spectral image varies between wavelength bands. therefore, the misregistration detection technique that does not utilize the luminance value is required. misregistration of the target image and the reference image is not a uniform process, and local misregistrations can occur in the image, which increases the difficulty of the registration process. therefore, calibrations cannot be easily performed using a method based on global characteristics. for image registration, both the reference image and target image are divided into several small regions. for non-uniform image misregistration, the images are divided into small regions, which are then calibrated. although a non-linear image registration method can be used to calibrate the distortion caused by misregistration, the method cannot be easily adapted for spectral images with considerable changes in luminance values. although our approach does not represent a fundamental solution to misregistration calibration because it is a region-based registration method, misregistrations can be sufficiently reduced to be ignored. several methods are available for dividing an image into small regions using the spatial frequency characteristics. in this paper, the image was evenly divided into four areas. next, misregistrations between the reference image and the target image are detected for each small region, and image registration is then performed. to align spectral images, we propose a calibration method that detects misregistrations by using a phase-only correlation method [11], which is a technique for calculating correlations by using a phase image. a phase image is normalized by the amplitude spectrum of an image. please note that this “spectrum” is not an intensity distribution for each wavelength of electromagnetic waves but a function of frequency. therefore, the proposed method can perform corrections without the figure 1 multispectral imaging system: (a left) system overview; and (b right) total spectral-sensitivities of the present system 62 cultura e scienza del colore color culture and science | 07 | 2017 | 59 68 nishi s., kimachi a., doi m., tominaga s. issn 2384-9568 doi: 10.23738/ccsj.i72017.05 influence of the amplitude spectrum in each spectral image. moreover, misregistrations can be detected with high speed and high accuracy compared with processing in the spatial domain. let both f(n1, n2) and gp(n1, n2) be n1 × n2 images, with image f(n1, n2) representing the reference image and image gp(n1, n2) representing the target image. one of eight spectral images is designated as the reference image. in this research, a spectral image with a center transmission wavelength of 670 nm was used as the reference image, and the remaining seven spectral images were used as the target images. figure 2 shows the procedure for detecting the misregistration of spectral images using the phase-only correlation. let f(k1, k2) and gp(k1, k2) be the 2-d discrete fourier transforms of the images f(n1, n2) and gp(n1, n2). therefore, f(k1, k2) and gp(k1, k2) are defined as follows: where k1 and k2 are discrete fourier indices; and wn1 = exp[-j(2π / n1)]; wn2 = exp[-j(2π / n2)]; |f(k1, k2)| and |gp(k1, k2)| are amplitude spectra; and θf(k1, k2) and θgp(k1, k2) are phase spectra. the cross spectrum c(k1, k2) between f(k1, k2) and gp(k1, k2) is defined as follows: where represents the complex conjugate of gp(k1, k2), and θ(k1, k2) = θf(k1, k2) θgp(k1, k2) represents the phase difference spectrum. therefore, the normalized cross spectrum cn(k1, k2) using the phase image is defined as follows: (1) (2) (3) figure 2 flow chart of the calculation process for the phase-only correlation. 63 cultura e scienza del colore color culture and science | 07 | 2017 | 59 68 image registration for a multispectral imaging system using interference filters and application to digital archiving of art paintings issn 2384-9568 where s(li) is the spectral reflectance, e(li) is the spectral distribution of illumination, rk(li) is the spectral sensitivities of the k-th sensor, and nk is noise. let ρ be an eight-dimensional column vector representing all spectral camera outputs, s be a n-dimensional vector representing the spectral reflectance s(li) and h (≡[hkj]) be an 8 × n matrix with the element hkj = e(li) rk(li). then, the above imaging relationships are summarized in the matrix form ρ = hs + n. when the signal component s and the noise component n are uncorrelated, a solution that minimizes the estimation error on s is the wiener estimator: where rss is an n × n matrix that represents the correlations among the surface spectral reflectances. we assume that white noise has a correlation matrix s2i. the surface normal vector at each pixel of an oil painting’s surface is calculated by using a photometric stereo method. if an object’s surface is a perfect diffuser, then the light intensity o reflected from the surface illuminated by a light source is described as o’=antl, where o’ is a normalized vector, l is the illumination directional vector, and a is the diffuse reflectance factor. the surface normal vector n is estimated from the above equation. a reflection model is required to render realistic images of oil paintings. in our previous study [12-14], we found that the surface reflection of most oil paintings can be described by the cook-torrance model [15]. the parameters of this mathematical model are estimated from the specular reflection component of the observed images. to detect the specular reflection component, we first calculate the output vector ρd for the diffuse component by using the estimated reflectance. next, the maximum sensor output rm of all observations is selected, and the difference ρs = ρm − ρd is defined. the specular function of the cook-torrance model is fitted to the specular data extracted from all pixel points. because the specular component at any pixel has the same spectrum as the light source, the parameters are estimated based on the statistical distribution of the specular component. let the intensity of the specular component be ||ρs||; then, the normalized specular component is represented as here, g represents the geometrical attenuation factor and f represents the fresnel spectral reflectance of the microfacets, respectively. v is the view vector. this component is calculated (4) the amplitude of the correlation peak represents the similarity between the reference image and the target image, and the coordinates of the correlation peak represent the relative misregistration of the two spectral images. however, if the misregistration correction is performed by dividing the image into small areas, then the overlapping of images near the boundary may becomes sparse. this problem can be resolved by separately preparing a small region that include the boundary and replacing the sparse region after performing the misregistration correction. the image misregistration correction is performed in the spatial domain after the 2-d inverse discrete fourier transforms. the fourier indices k1 and k2 that satisfy arg maxk1,k2 cn(k1, k2) correspond to the coordinates (n1 / 2 + x’, n2 / 2 + y’) of the target image in the spatial domain. the coordinates n1 / 2 and n2 / 2 represent the center coordinates of the reference image and the target image, and x’ and y’ represent the positional difference between the two images. if there is no difference in the image between the reference image and the target image, the values of x’ and y’ become 0, and the positions of the two images coincide. therefore, by moving the target image in accordance with the amount of x’ and y’ so that the difference between the two images is minimized, the image misregistration correction is completed. 4. applications to the digital archiving of paintings here, we describe a method for the digital archiving of oil paintings [2] based on the imaging system. the surface reflection of an oil painting includes the specular reflection or gloss. therefore, the camera output for the painting surface is composed of a diffused reflection and specular reflection. the reflection properties, the surface-normal vector and the surface-spectral reflectance are estimated from the diffuse reflection component, and the reflection model parameters are estimated from the specular component. to estimate the surface-spectral reflectance, the camera output is described as a model: (5) (6) 64 cultura e scienza del colore color culture and science | 07 | 2017 | 59 68 nishi s., kimachi a., doi m., tominaga s. issn 2384-9568 doi: 10.23738/ccsj.i72017.05 to minimize the squared sum of the fitting error where rsx and φx are the specular intensity and angle at pixel point x, respectively; d is the distribution function representing the micro facet orientation, which we assume is a gaussian distribution function; and γ and β are parameters that minimize the above fitting error, and they are solved according to the nonlinear fitting problem solution. image rendering is then performed based on all estimates of the surface reflection, which are the surface-normal vectors, the surface spectral reflectance, and the 3-d light reflection model parameters. 5. experiments 5.1. verification of calibration accuracy first, we performed experiments to validate the proposed correction method. although calibration charts are not required in this method, we used graph paper with numbers and letters as a calibration chart, which was examined to verify the calibration accuracy. the calibration results are shown in fig. 3. fig. 3 (a) shows the results of synthesizing a region of 1024 × 1024 pixels, which was extracted from the eight images acquired in the system. in this figure, the results of the case without the misregistration calibration are shown. a chromatic aberration is observed in fig. 3 (a), and the synthesized image appears unfocused. the image acquired by the system was difficult to use without calibration. fig. 3 (b) shows the calibration result. the misregistration of each of the eight images is detected by the phaseonly correlation method, and then registration is performed with the shift amount. the reference image is set to the image acquired with the 8th filter (the center wavelength is 670 nm), and the remaining seven images are corrected as calibration target images. the chromatic aberration has been drastically improved in comparison with fig. 3 (a). the misregistration calibration performed well. however, a slight chromatic aberration occurs, and registration in the horizontal direction is insufficient. therefore, although the chart is originally monochrome, a color is slightly perceived because of the nonuniform displacement or distortion in the image. because several regions cannot be calibrated by a global registration method, the image registration process was local. the results are shown in fig. 3 (c). the eight images in fig. 3 (a) are divided into small regions, misregistration detection and calibration by the phase-only correlation method is performed on each small region, and then the images are synthesized as a single image. the size of the small region is 256 × 256 pixels. the results show that the local registration can be calibrated with higher accuracy compared with the global registration. the chromatic aberration in fig. 3 (b) is corrected, and it is not perceptible in fig. 3 (c). the calibration results are almost identical with the original appearance of the chart. similarly, fig. 4 shows the calibration results for a color object. similar to the results shown in fig. 3, the local registration can be calibrated with higher accuracy than the global registration. these results show the usefulness of the proposed figure 3 calibration results of a original calibration chart: (a left) before calibration; (b centre) calibration without division; and (c right) calibration with division. figure 4 calibration results of a color object: (a left) before calibration; (b centre) calibration without division; and (c right) calibration with division. (7) 65 cultura e scienza del colore color culture and science | 07 | 2017 | 59 68 image registration for a multispectral imaging system using interference filters and application to digital archiving of art paintings issn 2384-9568 no. color patch de*ab 1 dark skin 1.581 2 light skin 1.335 3 blue sky 0.677 4 foliage 1.479 5 blue flower 0.913 6 bluish green 2.342 7 orange 2.299 8 purplish blue 1.313 9 moderate red 0.44 10 purple 1.081 11 yellow green 1.131 12 orange yellow 2.746 13 blue 1.825 14 green 0.603 15 red 2.388 16 yellow 2.588 17 magenta 0.654 18 cyan 2.73 19 white 1.356 20 neutral 8 1.19 21 neutral 6.5 0.648 22 neutral 5 0.397 23 neutral 3.5 0.561 24 black 1.629 average 1.413 maximum 2.746 0.2 0.4 0.6 0.8 1.0 400 500 600 700 r ef le ct an ce wavelength [nm] 0.0 estimate measured 01.dark skin 0.2 0.4 0.6 0.8 1.0 400 500 600 700 wavelength [nm] 0.0 estimate measured 02.light skin 0.2 0.4 0.6 0.8 1.0 400 500 600 700 wavelength [nm] 0.0 estimate measured 03.blue sky 0.2 0.4 0.6 0.8 1.0 400 500 600 700 wavelength [nm] 0.0 estimate measured 04.foliage 0.2 0.4 0.6 0.8 1.0 400 500 600 700 wavelength [nm] 0.0 estimate measured 05.blue flower 0.2 0.4 0.6 0.8 1.0 400 500 600 700 wavelength [nm] 0.0 estimate measured 06.bluish green 0.2 0.4 0.6 0.8 1.0 400 500 600 700 r ef le ct an ce wavelength [nm] 0.0 estimate measured 07.orange 400 500 600 700 wavelength [nm] estimate measured 08.purplish blue 0.2 0.4 0.6 0.8 1.0 400 500 600 700 wavelength [nm] 0.0 estimate measured 09.moderate red 0.2 0.4 0.6 0.8 1.0 400 500 600 700 wavelength [nm] 0.0 estimate measured 10.purple 0.2 0.4 0.6 0.8 1.0 400 500 600 700 wavelength [nm] 0.0 estimate measured 11.yellow green 0.2 0.4 0.6 0.8 1.0 400 500 600 700 wavelength [nm] 0.0 estimate measured 12.orange yellow 0.2 0.4 0.6 0.8 1.0 400 500 600 700 r ef le ct an ce wavelength [nm] 0.0 estimate measured 13.blue 0.2 0.4 0.6 0.8 1.0 400 500 600 700 wavelength [nm] 0.0 estimate measured 14.green 0.2 0.4 0.6 0.8 1.0 400 500 600 700 wavelength [nm] 0.0 estimate measured 15.red 0.2 0.4 0.6 0.8 1.0 400 500 600 700 wavelength [nm] 0.0 estimate measured 16.yellow 0.2 0.4 0.6 0.8 1.0 400 500 600 700 wavelength [nm] 0.0 estimate measured 17.magenta 0.2 0.4 0.6 0.8 1.0 400 500 600 700 wavelength [nm] 0.0 estimate measured 18.cyan 0.2 0.4 0.6 0.8 1.0 400 500 600 700 r ef le ct an ce wavelength [nm] 0.0 estimate measured 19.white 0.2 0.4 0.6 0.8 1.0 400 500 600 700 wavelength [nm] 0.0 estimate measured 20.neutral 8 0.2 0.4 0.6 0.8 1.0 400 500 600 700 wavelength [nm] 0.0 estimate measured 21.neutral 6.5 0.2 0.4 0.6 0.8 1.0 400 500 600 700 wavelength [nm] 0.0 estimate measured 22.neutral 5 0.2 0.4 0.6 0.8 1.0 400 500 600 700 wavelength [nm] 0.0 estimate measured 23.neutral 3.5 0.2 0.4 0.6 0.8 1.0 400 500 600 700 wavelength [nm] 0.0 estimate measured 24.black 0.2 0.4 0.6 0.8 1.0 0.0 method. next, we show the performance of the imaging system via reflectance estimation results using an x-rite colorchecker classic. the imaging conditions were as follows. the illuminant was an incandescent lamp. the distance between the system and the color checker was approximately 1 m, and the illuminance of the color checker surface was approximately 1000 lx. the color checker was captured with a shutter speed of 1/30 second, and the noise variance was assumed to be 0.01% of the signal component. the surface spectral reflectance of the color checker was estimated by a wiener filter using the image signals of the central 100 × 100 pixels of each color patch. the results are shown in fig. 5. the red curves represent the estimation results using the present imaging system, and the black curves represent direct measurements by a spectrometer. the estimation accuracy of the spectral reflectance was evaluated by the cielab color difference. the color differences de*ab under illuminant d65 are shown in table 1. the average color differences of de*ab for all 24 color patches was 1.413. the maximum color difference was 2.746 for no. 12 orange yellow. this experiment shows that the present imaging system has excellent performance. table 1 reflectance estimation performance by the present imaging system figure 5 estimation results of the surface spectral reflectances of a colorchecker. 66 cultura e scienza del colore color culture and science | 07 | 2017 | 59 68 nishi s., kimachi a., doi m., tominaga s. issn 2384-9568 doi: 10.23738/ccsj.i72017.05 5.2. estimation of the painting surface for digital archiving the oil painting shown in fig. 6 was preserved to a digital archive by using the present system and the proposed method. the vertical size of the oil painting is 15.5 cm, the horizontal size is 11.5 cm, and the surface has a matte appearance. the present system was placed perpendicular to the painting. the elevation angle of the light source was fixed at 45 degrees, and the azimuth angle of the light source illuminated the 8 directions at 45 degree intervals. to estimate the painting surface, the oil painting was initially captured with different shutter speeds (1/60 sec., 1/250 sec., and 1/1000 sec.). then, image calibration was performed by the proposed registration method, and high-dynamic-range (hdr) images were acquired. the reflection model parameter, the surface normal vector and the surface spectral reflectance were estimated from the acquired hdr images, and these estimates of the surface properties were integrated to render the oil painting. using this process, the oil painting was preserved as a digital archive. we estimated the surface normal of all pixels of the oil painting. the estimated result of the surface normal in the white dotted line area of fig. 6 is shown in fig. 7. fig. 7 (a) is a measurement of the painting surface with a laser displacement meter, and fig. 7 (b) is the estimate by the proposed method. in certain areas, the estimated surface shape is not clear compared with the measurement, and this lack of clarity is considered to be dependent on the resolution of the present system. a comparison of the results in fig. 7 with the shadow direction shows that the results match and the surface shape restoration via the surface normal estimation performed well. the spectral reflectance of the painting surface was estimated, and the experimental results of area 1 through 4 in fig. 6 are shown in fig. 8. the black line shows the measurement results obtained by a spectroradiometer, and the red line shows the estimation results. the measured value and the estimated value are substantially equal in all regions; thus, good estimation results were obtained. the three-dimensional light reflection model of the painting surface was estimated. figure 9 shows the fitting result into a three-dimensional light reflection model. the specular reflection component from the acquired image was extracted and then fitted to the gaussian function, which was assumed to be a specular reflection function of the cooktorrance mode. the reflection model parameters were estimated as γ = 0.063 and β = 200. the γ and β parameters represent the surface roughness and the specular coefficient of the area 1 area 2 area 3 area 4 figure 6 measured oil painting. 67 cultura e scienza del colore color culture and science | 07 | 2017 | 59 68 image registration for a multispectral imaging system using interference filters and application to digital archiving of art paintings issn 2384-9568 oil painting, respectively. the fitting results are shown in fig. 9, which shows that the reflection model parameters can be estimated with high accuracy. image rendering was conducted using the estimation results, and the results are shown in fig. 10. both light sources illuminated the oil painting at nearly the same position, and the spectral distribution of the light source was illuminant d65. the perceived resolution is inferior compared with that of the real photograph, which is believed to be related to the original 400 500 600 700 0.0 0.2 0.4 0.6 0.8 1.0 wavelength (nm) n or m al iz ed v al ue measurement estimation 400 500 600 700 0.0 0.2 0.4 0.6 0.8 1.0 wavelength (nm) n or m al iz ed v al ue measurement estimation 400 500 600 700 0.0 0.2 0.4 0.6 0.8 1.0 wavelength (nm) n or m al iz ed v al ue measurement estimation 400 500 600 700 0.0 0.2 0.4 0.6 0.8 1.0 wavelength (nm) n or m al iz ed v al ue measurement estimation 0 50 100 150 200 250 -20 -10 0 10 20 observed data gaussian fn. s pe cu la r i nt en si ty specular angle (deg) resolution of the system. however, because of the calibration performed by the proposed method, the chromatic aberration is barely perceived. this result shows that the color reproduction had a high accuracy. figure 7 estimated surface shape in the area with the white dotted line in fig. 6: (a left) measurement; and (b . right) estimated result after calibration. figure 8 estimation results of the surface spectral reflectances of oil paintings: from left to right (a) area1; (b) area 2; (c) area 3; and (d) area 4. figure 9 -fitting result to the gaussian function. figure 10 comparison with a photograph of an oil painting: (a-left) photograph of an oil painting; and (b-right) image rendering result 68 cultura e scienza del colore color culture and science | 07 | 2017 | 59 68 nishi s., kimachi a., doi m., tominaga s. issn 2384-9568 doi: 10.23738/ccsj.i72017.05 6. conclusions this paper has proposed a calibration method of a multispectral imaging system using interference filters. although the presented technology may not represent a tool for preserving cultural heritage artworks, we suggested one solution to the problem of digital archiving applications in multiband imaging using interference filters. the calibration method is based on the correlation technique in the frequency domain using the phase images of an acquired spectral image. by using the phase image to detecte misregistrations in the frequency domain, correlations can be calculated without the influence of changes in the amplitude spectrum. misregistration detection can be improved and conducted at high speed and with high accuracy. we described a method for applying this calibration method and the multispecral imaging system for the digital archiving of paintings. the feasibility of the proposed method and the present imaging system was examined by preserving an oil painting as a digital archive. the results demonstrated validity of the proposed method and imaging system. funding this research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. conflict of interest the authors declare that there is no conflict of interest. bibliography [1] y. miyake, y. yokoyama, n. tsumura, h. haneishi, k. miyata and j.hayashi, “development of multiband color imaging systems for recording of art paintings,” proc. spie 3648, pp. 218–225, 1999. 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