colour scheme

Lee Poulsen
Mon, 27 Sep 2004 12:36:15 PDT
> PRIMARIES: Red, Blue, Yellow
> SECONDARIES: Violet, Green, Orange
> TERTIARIES: Red-Violet, Red-Orange, Orange-Yellow, Yellow-Green, 
> Blue-Green,
> Blue-Violet
> You will notice that purple is not among these colours.  Also, fanciful
> names are missing, as they are too subjective.  If one was to place 
> these
> colour in a wheel, one would recognise the constituents of the 
> prismatic
> rainbow.

This is what I was taught growing up as a kid. (Although I didn't know 
the terms 'secondaries' and 'tertiaries' when I was a kid!) However, at 
least for me where I grew up (California and Texas), 'violet' and 
'purple' were basically synonyms. Grown-ups never distinguished between 
to the two when speaking to me. 'Purple' tended to be used more by us 
kids and 'violet' sounded more formal and "adult".

And I learned all about mixing blue and yellow to make green, blue and 
red to make purple/violet, and red and yellow to make orange. But if 
you look at the outer curve of the CIE color space diagram, a triangle 
with points at red, yellow, and blue encloses less of the colors than a 
triangle with points at magenta, yellow, and cyan (especially since 
subtractive, i.e., reflective color pigments are never as intense as 
colored light and therefore always form a smaller triangle overall). I 
think that due to two things, 1) the non-natural-ness of cyan and 
magenta in historical human color terminology, and 2) the resemblance 
of cyan as a shade of blue and magenta as a kind of overly intense 
pink/red, these two colors were just lumped in with blue and red. And 
therefore you ended up with red, yellow, and blue being the pigment 
primary colors. (Plus, I think sources for cyan and magenta pigments to 
make paints of those colors was very hard to come by in nature before 
the modern era of synthesizing compounds and synthetics. There are not 
too many teal and magenta rocks, minerals, animal products or plant 

However, you can get a much wider gamut or range of many different 
colors if you actually use magenta, yellow, and cyan/teal as your 
pigment primaries. And that's why virtually every color printer I've 
ever heard of, inkjet, laser, or other, uses those three colors. (As 
well as modern color printing processes which all seem to use the CMYK 
colors as their bases.) If you use a color laser printer very much, 
then you'll have had a lot of experience with the cyan and magenta 
toner cartridges (as well as the yellow and black toner cartridges) 
letting loose some of the toner and getting the brilliant cyan and 
magenta toner dust all over things from time to time.

Using the CMYK primaries, you get:

PRIMARIES: Magenta, Yellow, Cyan
SECONDARIES: Red, Green, Blue
TERTIARIES: Magenta-Red (rose red), Red-Yellow (orange), Yellow-Green 
(chartreuse), Green-Cyan (aqua), Cyan-Blue (turquoise), Magenta-Blue 

--Lee Poulsen
Pasadena area, California, USDA Zone 9-10On Sep 25, 2004, at 2:39 AM, 
Jamie wrote:

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