The Effect of Set Size on Color Matching

Current monochromatic sonar displays are soon to be replaced with chromatic ones. It is anticipated that color coding will enhance the performance of the sonar operators. A number of review articles, however, have pointed out that there are both advantages and disadvantages to the use of color coding. Used inappropriately, it may even degrade performance. The correct application of color coding depends on the nature of the task to be performed, the choice of colors, the number of colors, etc. This study sought to determine the effect of increasing the number of colors used in a color-coded CRT/display on the time required to match the colors. The time required to match a colored stimulus to one of a set of colors was measured as a function of color sets ranging in size from 2 to 10. Reaction time (RT) increased linearly with increases in set-size to five or six, after which the increase, although still linear was less steep. Mean errors increased sharply with set sizes of 9 and 10. The relative RTs to the different colors remained constant despite changes in the experimental method.