Upload
others
View
1
Download
0
Embed Size (px)
Citation preview
COLOUR
1. Colour and Percep0on– Sense and Reason We will: consider how our senses – specifically sight-‐ give us knowledge of the world; the difficulBes of achieving an objecBve assessment of colour sensaBon and why science and art interpret phenomena so differently. 2. Colour and Culture – Language and emo0on We will consider how our culture and gender effect our percepBon of colour. We will look at the relaBonship between words and sensaBons. 3. Colour in prac0ce – Pigments and light We will consider color and light as a material used in tradiBonal and digital media. We will deal with pigments and learn about subtracBve and addicBve color methods.
1. Colour and percep0on
The human eye can differenBate over ten million different colours. This image (when viewed in full size, 1000 pixels wide) contains 1 million pixels, each of a different colour.
The Physiology of sight The ReBna : Your ability to disBnguish colours is based on the sensiBvity of the cells in your reBna to the different wavelengths of light. There are 3 types of colour receptor cells -‐ called cones: one type is mainly sensiBve to violet-‐blue; one to yellowish-‐green and one to red. Light is reduced to three colour components by the eye. The three types of cones give signals according to the extent they are sBmulated. The reBna also contains rods that have a different response curve; in normal light they do not contribute to vision but in dim light the cones are under sBmulated so sight comes from the rods which record light and dark but not colour. (Rods are only parBally responsive to red light) The Brain: Colour informaBon is transmiSed to the brain by three opponent processes derived from the cones: red-‐green, blue-‐yellow and black-‐white (this explains why you cannot see „reddish green‟ or „yellowish blue‟).
Are we all seeing the same colours? Most humans are tri-‐chromaBc, which means they have 3 types of colour receptors but many animals are tetrachromats, meaning that they have 4 types of receptor (birds, repBles and some fish). Up to 50% of women are tetrachromaBc but only a small number of men. Not all, but some, of those who are tetrachromaBcs have the ability to make enhanced colour discriminaBon.
HOW MANY HUES CAN YOU SEE?
Derval Color Test TM, (c) DervalResearch -‐ www.derval-‐research.com
RESULT Fewer than 20 color nuances: You are a dichromat, like a dog, and have only two types of cones (25% of the populaBon). Between 20 and 32 color nuances: You are a trichromat. You have three types of cones in the purple/blue, green and red area (50% of the populaBon). Between 33 and 39+ color nuances: You are a tetrachromat. Like bees, you have four types of cones (25% of the populaBon).
The problem of objec0ve reason. The Muller-‐Lyer illusion. Which line is longer? There are different ways of knowing the line: we can take an objec0ve (scienBfic) measurement or we can follow our subjec0ve experience. Our culture gives a higher value to objecBve knowledge, which is a_er all the basis of science, than to the subjecBve experiences of our senses yet it is through our senses that we understand the world. If one line „feels‟ longer – in our first sensory experience-‐ than the other, then should we regard it as longer even if the measurement suggests otherwise?
Gestalt Gestalt psychology is an aSempt to understand the laws behind the ability to acquire and maintain meaningful percepBons in an apparently chaoBc world. “Why does the moon always appear larger near the horizon than at the meridian?” Because we judge the size of an object by comparing it to the surroundings Look at a colour illusion and you will understand why some philosophers decided to concentrate on abstract knowledge rather than sensory experience. What is the true colour of the dots?
Colour as understood before Newton Classical philosophers noted the eye’s incapacity to judge the true nature of things. Aristotle in his „On Sense and Sensible objects‟ suggests that “the intermediate colours arise from the mixture of light and dark”.
God Covenant with Noah, The Vienna Genesis, 6th century. The green of water signifies the Deluge and the red the Last Judgment Day.
ASempt at true-‐colour spectrum, wavelength in nanometres marked
1. Name the colours that you see in the order that they appear.
2. Draw a circle and divide it into what you consider to be an accurate division of the rela0ve area taken by each color. 3. How many colours are there in the spectrum?
Newton and aYer In the 1660’s as a result of his observaBons with prisms Newton proposed that colour was simply a funcBon of the variable refracBon of white light. Red had the least refracBon and violet the most. Newton divided the spectrum into seven colours: red, orange, yellow, green, blue, indigo and violet. He did this as he wanted to link colour to the number seven. As a ChrisBan he believed that God had created the world to follow a divine paSern; not only had he done so in seven days but so that seven was the basis of the world‟s order: the seven days of the week; the seven known objects in the solar system and musical notes. In his diagram above Newton shows the spectral colours in relaBon to the musical notes. He has interpreted his apparently objecBve evidence in accordance with his subjecBve cultural beliefs.
Do we only see what we know?
Phenomenology ‘Phenomenology is a branch of philosophy that deals with what you see, feel etc in contrast to what may actually be real or true about the world’ Oxford DicBonary The philosopher Merleau Ponty used this illusion to illustrate the value of the subjecBve as a „natural‟ pre objecBve vision; one which is usually ignored by science. He argued that sensa0on was an element of knowledge which was oYen ignored by science sugges0ng that science is a schema0za0on (plan or diagram) of the world in the same way that Geography is a schema0za0on of the landscape; neither show things as we experience them.
How does our prior knowledge affect what we see?
GOETHE’S THEORY OF COLOR SkepBcal of Newton's theory of color, Johann Wolfgang von Goethe began his own studies in the late 1780s and published Theory of Color (Zur Farbenlehre) in 1810. The crux of his color theory is its experienBal source: rather than impose theoreBcal statements (as he felt Newton had), Goethe sought to allow light and color to be displayed in an ordered series of experiments that readers could experience for themselves.
Through his «delicate empiricism» Goethe developed the no0on of complementary color, aYer image and colored shadows.
“It is a calamity that the use of experiment has severed nature from man, so that he is content to understand nature merely through what arCficial instruments reveal and by so doing even restricts her achievements...Microscopes and telescopes, in actual fact, confuse man's innate clarity of mind.” "The human being himself, to the extent that he makes sound use of his senses, is the most exact physical apparatus that can exist."
Experience is what directs arBst’s choices in color. Here are some examples:
SPATIAL EFFECTS OF COLOR AND SHAPES
2. Color and culture
Lawrence Alma-‐Tadema, Phidias Showing the Frieze of the Parthenon to his Friends, 1968, Birmigham Museum and Art Gallery, Birmigham
WHITE “Color contributes to beauty, but it is not beauty. Color should have a minor part in the consideraCon of beauty, because it is not color but the structure that consCtutes its essence. “
Johann Joachim Winckelmann.
Canova, Napoleon as Mars the Peacemaker, 1802-‐1806, Apsley House, London
1858 Gladstone's explanaBon of Homer's colour terms was taken as the suggesBon that he and the other ancient Greeks were colourblind. Gladstone denied that he suggested here the Greeks suffered from colourblindness, though, and he later said: "My meaning was substanBally this: that he [Homer] operated, in the main, upon a quanBtaBve scale, with white and black, or light and dark, for its opposite extremiBes, instead of the qualitaBve scale opened by the diversiBes of colour."superiorità della razza bianca, inferiorità delle culture affascinate dal colore In Western art tradiBon, white acts as the mark of the superior white race over non-‐Western underdeveloped cultures who find color fascinaBng. Color has been considered female, irraBonal, insBcBve, childish by the dominant male autority. White has been used as part of propaganda strategy. James Hoban,, White House, 1792-‐1800, Aquia Creek sandstone painted white, Washington D.C.
Olympia Part One: FesBval of the NaBons (Leni Riefenstahl, 1938)
3. Color in prac0ce
Although today many pigments and dyes are syntheBc, our ancestors managed to obtain a wide spectrum of colors from mineral, plants and animal sources long before chemical equivalents were manufactured. Those most rare and difficult to obtain became symbols of wealth and status. ArBst's paint consists primarily of two components: pigment and binder. In order to produce paint, pigment and binder are ground into a sBff paste which must have three requirements: it must be brushable, it must adhere permanently to the support's surface and it must not alter significantly in Bme. Pigments are insoluble color parBcles that require a binding agent to hold them onto the surface of the material being colored. The binder, commonly called vehicle or also medium, is the film-‐forming component of paint. A pigment should not dissolve in the binding medium nor be affected by it. In oil painBng for example, linseed oil is the binder . Many colors, such as lead white or umber, accelerate the drying of the oil paint; others, such as the lakes and vermilion, retard this process. In general the dense, heavy pigments dry well and quickly, since they require liSle oil. Watercolor uses gum arabic as binder, tradiBonal tempera paint uses egg yolk, acrylic paint use a plasBc polymer.
Cave painBngs by early man show the early use of pigments, in a limited range from straw color to reddish brown and black. These colors occurred naturally in charcoals, and in mineral oxides such as chalk and ochre. Most of matural pigments nowadays have been replaced by cheaper and less toxic syntheBc pigments.
The Milkmaid by Johannes Vermeer (c. 1658), shows his use of expensive pigments, including Indian Yellow (urine from Indian cows fed only on mango leaves), Lapis lazuli, and Carmine. The only way to achieve a deep rich blue was by using the semi-‐precious stone Lapis lazuli to produce a color known as ultramarine. Because the best sources of lapis lazuli were remote, the stone was expensive, and was later replaced by azurite and smalt (minerals) and indigo (biological).
Please visit the following website to know more about colors and pigments and to invesBgate how arBsts ‘ paleSe changed across the Bme:
hSp://www.webexhibits.org/pigments/intro/history.html
Dyes are colored substances that change the color of other materials permanently. They are soluble substances, though some become insoluble a_er they have been applied. They have a special affinity for the substrate they color. Tyrian purple was extracted from shellfish of the Murex genus, tradiBonally harvested near Tyre in the eastern Mediterranean. Phoenicia (present day Lebanon) was famous for the color of its Tyrian purple and became a big producBon center. The cloth was prized by the Romans, and used in the fine robes of kings and emperors.
Fragment from an 11th-‐century ByzanBne robe with griffins embroidered on a silk woven of murex-‐dyed threads, Église de Valére, Sion, Switzerland
Carmine is much more concentrated than the tradiBonal red dyes of madder root, kermes, Polish cochineal and brazilwood. It was in high demand throughout Europe, coloring the fabrics of royalty, nobility, and church leaders. Michelangelo used carmine in his paints, and the dye lent disBncBon to the uniforms of the BriBsh Redcoats, the Hussars, the Turks and the Royal Canadian Mounted Police.
Cochineal comes from the cochineal insect, which produces carminic acid to protect itself from its insect predators. Carmine dye is made from carminic acid, which is extracted from the female beetles’ body and eggs. This deep crimson dye is used to produce scarlet, orange, and other shades of red, and is found in cosmeBcs and as a food colorant.
Please visit the following website to know more about colors and dyes:
hSp://www.webexhibits.org/causesofcolor/7.html
Wolfgang Laib, Pollen from Hazelnut, 2013, MOMA New York
Luca Vitone, Räume (Rooms), 2014, exhibiBon view Neuer Berliner Kunstverein