The technique described results in a display gamma function where the contrast between each of the steps is equally discriminable. Digital cathode ray tube (CRT) (and film) displays set up using this technique tend to have high image quality as judged by reconnaissance image interpreters. The procedure starts with a set of 51 photometric measures of a specific set of digitally-controlled targets designed to determine the interaction between the display's target and surround luminances, and the display's useful luminance range. These data are used in the Rogers-Carel formula for predicting visual threshold of within-target modulation contrast, m, as a function of target luminance, surround luminance, visual size of the target, and spatial frequency of detail within the target. Through curve fitting, optimization of viewing distances, and other operations, the equation is reduced to m = f(1), where (is the luminance when all the display pixels are commanded to the same level. This equation is used to determine the number of just noticeable differences (JNDs) within the useful display luminance range and then to determine the luminance value for each command level so that each succeeding step represents the same number of JNDs.