“Thought, as we have so far described it, is what it is by virtue of becoming all things, while there is another which is what it is by virtue of making all things: this is a sort of positive state like light; for in a sense light makes potential colours into actual colours.” - Aristotle.

Didn’t follow what Old A said, but it’s quite an impressive quote to put at the start of a chapter on light and colour.

A white shirt reflects almost all the light falling on it, and a black skirt absorbs almost all the light, stingily not reflecting anything, and appears black. Thus white is the sum of all colours and black is the absence of same. I like to believe that there’s no perfect white or perfect black on earth.

Goethe swore. Newton was a scientist and Goethe was a poet. Goethe tried to explain poetically what science could not. For Goethe, colour had emotion, and was of the senses and science can’t do justice to its definition. Ludwig Wittgenstein’s ‘Remarks on Colour’ takes a philosophical approach to colour. Read them all, and keep quoting them and bored people will swear you are a killing authority on colour!

Now, to get on with mixing colours, take red first. Let’s mix red with yellow. Imagine a pool of yellow paint and red poured into it. Orange! The proportions of red and yellow may be changed to give a range of oranges. Likewise, green is born of yellow and blue parents. Violet from red and blue. Clear?

Red, Blue and Yellow are pure colours, colours that can’t be derived by mixing other colours. They are called Primary Colours. Primary Colours intermix to form Secondary Colours. Tertiary Colours are colours obtained by mixing a Primary Colour and a Secondary Colour. Examples are Blue-Violet, Reddish Orange, Turquoise… but this concept is only a technicality and need not detain us.

Children have a different set of primary colours. They learn to recognize Red, Blue, Green and Yellow first. Black and White, too. Only after they know these colours do they approach Brown, Violet, Orange and Pink. Later, much later, kids learn ‘Grey.’

One way to explain a colour would be to talk of its hue, saturation and lightness. ‘HSL’ in your comp programs. ‘L’ is also called luminosity. Hue is what makes a colour red or green or blue; when you move from hue to hue, you are traveling across the rainbow. Saturation means how rich. Remember your chemistry? Dissolve sugar in water till the water can’t take anymore, that’s 100% saturation. Tho Thweet! No sugar is 0%. What you get if the doc says so.

Lightness is how dark or how light the colour is. Pastel shades are very light and dark shades are almost black. In my young days as a budding art director, I designed a brochure with beautiful pastel colours like chalk, mauve and a barely visible pale green. It looked all right on the comp, and client loved the design. But the printers goofed up and I got a brochure with the colour scheme of a doctor’s coat! We lost the client but learnt a lesson. Now I play extra safe with print design and experiment with pastel shades only for web design and slide shows where you can make a distinct colour that is only a few values greater than white.

When you scientifically look at colour schemes, you can also choose between additive and subtractive colour models. Additive, not addictive, you doper! Additive models are when you are looking at colours in a light source, like a dirty picture in a websiteon your comp monitor or newsreader on TV. Subtractive models are useful when dealing with reflected light, as in a printed picture of a glamour doll in a mag.

Another thing to do, children: Take out your nice new magnifying glasses and a printed photograph in a nice new magazine. Now, please look at the pictures through the lens. Yes, the nice picture of the pretty lady. No, not that one, she hasn’t any clothes on. Naughty! The pretty aunty has come out in nasty spots, hasn’t she? But, please understand that these spots of red, blue, yellow and black mix visually to make all the pretty colours you can think of.

CMYK: This is the popular subtractive model used for printing. The letters stand for Cyan, Magenta, Yellow and Black. ‘K’ is used instead of ‘B’ for black or some fool will thing it’s blue. These gurus pre-empt everything and make it foolproof! Cyan, Magenta and Yellow are pure colours that will combine with each other to produce any colour under the sun. Why Black? That’s because printers wanted to independently control the intensity of black and produce dark pictures. Try printing a colour picture on your desktop printer after removing the black cartridge. The colour cartridge is technically capable of producing all the colours necessary, but you will only get a pale version of the original pic on your comp monitor.

The brightest white to be had from printing using CMYK is the white of the paper. Printing people are mathematical; they’ll refuse to discuss Navy Blue or Sky Blue with you. They understand and feel safe with percentages of C, M, Y & K.

An art director of an ad agency I worked in before, once asked an experienced print man to use Sky Blue on the cover of an annual report. Must have been a grey morning for the chap, because he saw red at this ‘blue’ request by a green designer. He grabbed my friend by the shoulder and took him to the window. “Look at the sky,” he said, “And tell me what the colour of the sky is.” The sky, then, was a dull grey.

The sky blue in my graphic software is 50% Cyan but somebody else may think 30% Cyan is sky blue. There’s safety only in numbers. Print technicians are hardcore pros, they understand only specifics. And that goes for Parrot Green, Signal Red, Navy Blue and Chocolate Brown. 50C 100Y makes better sense to them than Charteuse or Yellowish Green. BTW, why Cyan; why not Blue? Isn’t what was good for Newton good for you? No, because Cyan is the primary blue for printing purposes. It will breed many colours when mixed with other primaries, but can’t be obtained by mixing any other colour. And Magenta, which looks more purply than a primary colour ought to be, is another primary. Yellow is usually yellow, but the printer’s yellow, or Process Yellow is neither a reddish yellow or a greenish yellow: it is a pure yellow. Take a trip to a friendly printing press to understand the process better. Also fiddle around with the colours of a graphic software.

The RGB concept springs from the trichromatic theory of Thomas Young. (pic)

Our eyes contain three different types of color receptor equipment called cones, each type being receptive to light of different wavelengths. Incoming light signals trigger the respective cones according to their wavelength. Some cones recognize red, some green and the rest blue, giving us the RGB model. The RGB model is an additive system, used for light sources like your TV or comp monitors. Beware: if you design something to be printed using a comp’s software, the colours when printed look less bright finally on paper. Obviously.