The mixture of two hues exactly opposite each other on the color weel such as red green, blue orange, or yellow and violet result in neutral gray or brown. Complementaries present an equal balance of three primaries, a different result than adding neutrals. In these examples we can see how one color beside another changes the character of other colors. In the first image closely related, low intensity colors are used to create a soothing atmosphere. In the second image, high intensity shapes create a contrast against a soft background with low saturation of color.
Blues tend to recede into the picture plane, while warmer hues come forward.
These effects are dependent upon each individual work of art. In the painting below by Cezanne, the warms come foreward and the cool colors recede. However, in the abstract painting by Howard Hodgkins, the sharp blue shape in the center of the composition moves forward because of the scale and power of that color. Mixing the value changes of a color by adding black and white. Recognizing the value of a pure hue by matching it to a gray scale.