Color Reaction & Coaction

Let's think for a minute about how a color relationship works visually, how two colors act on each other. They act in two very different, opposite, ways.

One way is that they "co-act" with each other, producing the impression of the hue, luminosity, and intensity common to them both. In the first example, the hue of the leaf figure combines with the background hue to produce a yellow-orange feeling; and in the second example, a yellow-green feeling. Lighter and darker colors co-act in the viewer's brain to produce a feeling of medium luminosity. Higher-intensity and lower-intensity colors co-act to produce a feeling of moderate intensity.

The other, opposite, way is that they "re-act" to each other, one color making the second color look less like the first color. In the first example, the shaded yellow hue of the leaf figure reacts to its orange background, looking less orange and more green than the leaf figure in the second example (the exact same color, painted from the same jar), which looks less green and more orange.

Lighter and darker colors re-act to look even lighter and darker than they "are".

Higher-intensity and lower-intensity colors re-act with each other and appear to be even higher and lower intensity.

Colors co-act and re-act with each other simultaneously. That's the double color action which doubly stimulates the eye and brain. But, you can focus on one or the other for fun, and when working at choosing colors for the kind of relationship you want.

Color Reaction & Coaction

William Tapley
Art of Color