What are Trichromatic and Opponent Color Process Theories?
There are two major perceptual theories in color vision. Most people are familiar with Trichromatic Color theory, which posits the existence of three cone types. While Trichromatic Theory explains why 3 primaries are sufficient to match any sample, it cannot explain many other aspects of color vision. A second theory, Opponent Process Theory, is better at accounting for many color phenomena such as simultaneous color contrast, chromatic adaptation and complementary hues. Designers are less often knowledgeable about Opponent Process Theory, which is unfortunate because it is more directly related to appearance of surface colors. Moreover, Opponent Process Theory has practical significance: many studies find that color manipulation through Opponent Process pairs is far more intuitive and easier than through the usual control of three RGB values or of X,Y and Z CIE values. The basic assumption of Opponent-Process Theory is that colors come in pairs. The “achromatic system” of black-white
