tobyaw: (Default)
Toby Atkin-Wright ([personal profile] tobyaw) wrote2009-02-06 09:25 am
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Primary colours revisited

I was interested by the results of my poll last week. The most popular choise was "Red, Yellow and Blue", which I guess is what we were all taught to be primary colours in art classes at school; primary colours from primary school.

A dictionary definition of primary colours says 'those from which all others can be derived' (Chambers Consise Dictionary), and goes on to list several possible combinations of colours that could be considered primary colors. There is no single set of colours when it comes to primary colours

Looking at the answers I provided in my poll:

  • Red, Yellow and Blue The basic simple answer, and arguably the wrong answer. Because red, yellow and blue aren't evenly spread around the spectrum, mixing them gives only a limited gamut, meaning that some colours can't be produced, including bright greens, cyans and magentas.
  • Red, Yellow, Blue and Green Artists became aware of the limitations of red, yellow and blue, and added green to the mix to enlarge the gamut. Leonardo da Vinci used RYBG (together with the addition of black and white). The Insights wheel uses RYBG.
  • Red, Green and Blue The common additive primary colours, used for mixing coloured light, RGB is used in computer monitors and televisions. All colours on web pages are expressed in RGB.
  • Cyan, Magenta and Yellow The subtractive colour model is used for mixing paints, inks, and the like. Black is added (refered to as K) because practical problems in mixing CMY don't allow the mixing of a pure black, so it is often referred to as CMYK. Almost all printed colours will have been expressed in CMYK.

So a simple conclusion: all the options in the poll are primary colour except for 'Red, Yellow and Blue'.

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[identity profile] the-magician.livejournal.com 2009-02-06 10:39 am (UTC)(link)
I fault your conclusion

Your poll asked
Which of these do you think of as primary colours?

And my answer of RYB is indeed what I think of as "primary colours" as that is how they are taught in Fine Arts (http://painting.about.com/od/artglossaryp/g/defprimarycolor.htm) which, according to that link, makes them primary colours because you can't create those colours by mixing other colours together (in paint or similar media). They are the "Primes" of the paint world.

Having done printing design for conventions for twenty years now, and worked in technical documentation (including product pack design), I have more than a passing knowledge of printing terms and design terms so I know about colour separations for printing and the various colour models :-)

And of course these colour models totally ignore some of the other essentials of how something appears visually, such as the matt->gloss range. There is a particular trick in portrait painting where the artist uses nice shiny oils for most of the picture, but paints the pupils of the eyes in matt black, so that the light "falls into" the painting there and because of the lack of shine, the eyes seem to follow you around the room ...

So yes, RYB are primary colours, in a particular arena and for a particular meaning of primary colours.
ext_8559: Cartoon me  (Default)

[identity profile] the-magician.livejournal.com 2009-02-06 11:21 am (UTC)(link)
Your conclusion was
"So a simple conclusion: all the options in the poll are primary colour except for 'Red, Yellow and Blue'."

So I still fault your conclusion.

"Your comment about RYB primary colours..."
While it was *in* my comment, it was referring to the linked site claiming that. And yes, mixing magenta and yellow (http://www.wetcanvas.com/forums/showthread.php?s=&threadid=99008&pp=15&page=1) produces red ... though that link points out that with real pigmented paints getting certain vibrant "true" reds may be impossible.

And you didn't mention the Hue/Chroma/Value (http://www.greatreality.com/color/ColorHVC.htm) colour model either :-)