CS 552, Spring 1998

General Guidelines Based on Color Studies and Practice

Guidelines based on computer display technology

(1) Where possible, use hardware-independent "standard" color values, at least as a baseline RGB value that you will modify.

(2) Be sure the duration of an image is long enough to allow the perception of color.

(3) Alternating colors too quickly will cause them to be perceived as a single, fused color.

(4) Display colors should be selected experimentally, not mathematically.

(5) To reduce the effects of flicker, use dark colors for backgrounds, large expanses of color, and dense text.

(6) Put light colors next to dark colors to remain compatible with monochrome displays and to adapt to the constraints of projection technology.

Guidelines based on psycho-physical effects

(1) Vary color along more than one dimension to maximize discrimination.

(2) Avoid subtle distinctions in color codes.

(3) Juxtapose different colors to be compared, particularly similar ones.

(4) As the number of colors increases, increase the size of small images.

(5) Font and line width are at least as important as color in establishing legibility.

Guidelines based on cognitive effects

(1) Use color sparingly.

(2) Use the four "focal colors" to encode information that needs to be remembered.

(3) Minimize the amount of coding the user is expected to learn and re-learn.

(4) "False coding" will confuse and frustrate users.

(5) "Overloaded colors" will confuse and frustrate users.

(6) Color use must be meaningful and consistent to facilitate searching or tracking.

(7) Provide labels or legends with colors when the meaning is not obvious or when several meanings must be remembered.

(8) Use names, rather than numbers, to describe colors.

(9) Use redundant cues to augment color coding.

(10) Where possible, match hues with conditions or actions being represented.