Artists traditionally refer to red, yellow, and blue as primary colors. These three colors were once believed to be the essential set for mixing a broad palette in painting. Following this line of thinking, violet, green and orange become secondary colors because they’re mixed from the primaries. However, for more than a century, both scientific understanding and practical experience has shown that cyan, magenta, and yellow are more efficient for subtractive mixing with pigments, producing clearer and a more saturated range of colors. That’s why printers use those three primaries, designated as CMY (actually printers use CMY plus black). Additive primaries In other artistic and technical fields, there’s another set of primary colors. Red, green, and blue (RGB) serve as additive primaries in digital displays, photography, and theater lighting. If you talk to photographers and lighting designers, they regard yellow as a secondary, achieved by mixing red and green. The persistence of the red-yellow-blue model in art education is due largely to historical convention rather than optimal color mixing. One of the first things new painters discover is that it’s hard to mix a vibrant purple with those classic grade-school primaries. I once asked my brother, who taught kindergarten, if we could shift a child's understanding of color, and teach them a different set of primaries than the red-yellow-blue set. If we started them young, maybe kids could learn that all six of those colors are primary: namely yellow, red, magenta, blue, cyan, and green. But he said forget it, that's easier said than done. Colors are far too deeply ingrained culturally. I’ll admit, it took my brain more than a year to map cyan and magenta as distinct primaries, and not just a kind of blue and a type of red. What’s a practical solution? A practical approach is to recognize that “primary colors” are not a universal set given by God or nature, but the set you use, and the way you map the world of color depends on the context and your goals. When the aim is to achieve the widest possible gamut from a set of three starting colors, then cyan, magenta, and yellow for pigment, or red, green, and blue for light, are scientifically preferable. It doesn’t mean you have to look for pigments that match those printer’s primaries, but rather that you calibrate your eyes and brain to map the world that way. Understanding the strengths of these systems allows artists to adapt their color choices deliberately, depending on whether they are mixing paints, working digitally, or designing lighting. Limited and subjective primaries If you’re using paint and want the purest, most highly saturated color, you’ll probably want your starting palette to include more than three colors. You might want to have each of the six primaries (yellow, red, magenta, blue, cyan, and green) represented by their equivalent pigments. Painting by Charles Bell However, many artists don’t want to represent all those bright colors in their paintings, and especially not in any single painting, unless you paint gumball machines or something. So they intentionally choose limited or even idiosyncratic primary palettes. Sometimes they favor the traditional red, yellow, and blue, or even more restricted three-color or triadic palettes. The goal with restricted triads is not to maximize the gamut of potential mixtures—but rather to explore the subjective relationships and expressive harmonies that arise from their interactions. Using a limited gamut can help artists evoke certain moods, reinforce stylistic unity, or experiment with how a small set of colors can suggest the effects of light and atmosphere beyond literal representation. This subjective approach can yield powerful artistic results, reminding us that the choice of primaries is as much about creative intent as about scientific accuracy. If you like this kind of stuff, you’ll love my book Color and Light: A Guide for the Realist Painter, and my video Triads: Painting with Three Colors. Links take you to my website. Leave a comment Share