We're taught growing up (or at least we are in the USA) that red, yellow and blue are the primary colours - that all secondary and tertiary colours can be mixed from them. We're shown a colour wheel, which lays out how everything interacts, and all the colours seem to be there.

Everything seemed in order until one morning a month or two ago, I woke up and wanted to paint a piece with the scheme black, yellow and magenta. I dug around in my box of paints, which is short on fancy colours but has plenty of red, yellow, blue, black and white. I mixed and mixed and mixed and... well, magenta never materialized.

Granted, light and pigment primaries are a yin and yang, but I never gave any real thought to print primaries - inkjet printers and all other four-pass process systems (magazines, product packaging, etc.) use magenta, yellow, cyan and black ink to create all other output colours.

Primary colours, by definition, 1) cannot be mixed from any other colours and 2) can be mixed to create all other colours. Magenta is a pure hue which must be bought, and can then be mixed with yellow to create red. Cyan is a pure hue which can be mixed with magenta to create "primary" blue.

What I'm driving at here is obvious, and I want to know if I'm going crazy or if I just overlooked something that's old news to everyone else. I'm in my twenties and I've only once heard someone else agree that magenta, rather than red, is the primary. As a lifelong artist who is continually experimenting at home and has taken a brazillian art classes (including colour theory), the notion that red is not a primary colour rocks the very foundation of my understanding of colour - the Holy Trinity is not composed of the three entities I thought it was!

This is probably obvious to anyone in the professional printing business, but it should be just as obvious to someone working solely in pigments. If I'm not going crazy here, then I think the red-yellow-blue dogma is a serious misinformation. Colour forms the foundation for so many other disciplines and we're so conclusively taught to start at red, yellow and blue. I don't want more aspiring artists growing up thinking that, too.

Am I mistaken, or going crazy? Or just wasting my time caring?
Either way, for the time being I'm off to buy some magenta pigment....

You are not crazy. There are actually two sets of primary colors. One for reflected color and one for transmitted color.

The color wheel we first learned is for reflected (color is reflected back to us) color and is based on the primary colors Red, Yellow and Blue. By mixing red and blue you should get a starting red-violet that you can make to look like magenta by adding the complimentary color (across the color wheel) and some pure white? It may be less frustrating, but expensive these days, to just buy the desired color.

The other color wheel is for transmitted (color is transparent for purposes of argument as in a transparency or the layers on a real photograph) color and its primary colors are Cyan (C), Magenta (M), and Yellow (Y). Black (K) is an enhancement layer for printing. Printing industry tradition stems from when printers got film transparencies and had to make separations for each of these colors by filtering out all the others. Each color still gets it own plate or inkjets. Photographers still using film will color balance by adding or substracting these three primary colors.

The CMYK tradition has carried into the desktop printer World making it all very confusing at times.

Hope this helped.

this is kind of interesting
colour perception

We aren't able to reproduce all colors anyway. Here's an article about the complete color space: http://en.wikipedia.org/wiki/CIE_1931_color_space (Mind especially the picture)

Here you can see how different systems match (only) parts of this color space: http://de.wikipedia.org/wiki/Bild:CIE_RGB-CMYK-Beleucht.png

i know when i went from my old computer to a new computer most of the colours in my palettes changed a great deal

ms wrote:

i know when i went from my old computer to a new computer most of the colours in my palettes changed a great deal

Did you calibrate the monitor?