Color has a number of physical and perceive characteristics that are described by various representative systems, i.e., color spaces. Each of the possible color spaces is described by a three dimensional system of related characteristic. For example
For this discussion, lets concentrate on the HSI color space since the hue and saturation of colors respond closely to the way humans perceive color.
Intensity contains most of the "spatial' information in a scene, and the human visual system processes this first. After this has been processed, the eye then recognizes the hue and saturation of what it is viewing.
One photographer recommended squinting in order to perceive the overall balance of intensity of a scene.
Are desirable in any painting or photograph, and can be used together to create harmony.
If you place the Primary and Secondary colors on a 'Color Wheel' you will find that
Always look for complementary colors
Certain colors 'react' very strongly with each other to give "Strong Contrasts' and to many people these will become 'Discords' rather than 'Harmonies'.
Monotone achromatic: neutral colors only, white, black gray. Easy to use but requires expert care to avoid complete boredom. See the Next interface as an example of how effective a neutral design can be.
Monotone chromatic: a single chromatic color ranging in brightness and saturation: red, pink, rose, etc. Easy to use but again risks monotony.
Analogous hues: two or three colors close to each other in color space: blue-greens, etc. Easy to use.
Complementary hues: contrasting hues: blue-orange, red-green. Requires care since it can appear garish and unbusinesslike. Works best when the two differ significantly in brightness and one is relatively desaturated, , e. g., a dimmer, desaturated red and a brighter saturated green.
Split complementary hues: uses three colors, one base color plus two, near, but not directly across, color space: orange with blue-greens. Works best when colors from opposite sides differ significantly in brightness and color(s) from one side is/are desaturated. Usually produces a less garish feeling than a simple complementary scheme.
Triad hues: uses three hues approximately equidistant in color space: red-yellow-blue. Desaturate at least two hues. Triad schemes are often embedded in a generally neutral field, so it would work well on a typical Windows gray background.
Tetrad color: uses 4 hues at equal intervals in color space: yellow-green-orange/red- blue/violet. Leave this to the experts.
Colors are also commonly associated with a psychological "temperature" and are divided into warm and cool categories.
Reds, oranges and yellows produce a warm and active feeling. They also appear to advance toward the eye because they seem nearer than they actually are.
The cool colors are blues, greens and violets. Tints of these colors create a restful and soothing feeling unless they are too intense in chroma. Cool colors are also known as receding hues since they appear farther away than they actually are.
In nature, atmospheric conditions cause objects that are father away to loose their intensity. This mental conditioning suggests that some colors advance toward us while others recede.
The meanings that people attach to color changes with culture and context. For example, blue can sometimes mean power and at other times sadness.