Visual determination of hue suprathreshold color-difference tolerances using CRT-generated stimuli

Suprathreshold hue color-difference tolerances were measured at four color centers using CRT-generated stimuli. The tolerances, defined using CIELAB, were measured using two different methods of presentation. In the Absolute Experiment, the stimuli were presented at luminance levels that matched those of the previous object-color experiments, so that the CRT stimuli were nearly metameric to the originals. In the Relative Experiment, the white point of the monitor was defined as L* = 100 at a corresponding chromaticity to the object-color viewing environment, but at a lower luminance level. The results from these two experiments followed the same general trends; however, they were significantly different from each other for three of the four color centers. The same trends were seen in the object-color results, although neither CRT experimental condition produced tolerances that were conclusively more similar to the object-color results than the other. The feasibility of the use of the CRT has been demonstrated. It is likely that parametric effects of stimulus presentation are the cause of the differences in results among the different experiments, as opposed to differences in the mode of appearance. These parametric effects can be studied more quickly and economically using a computer-controlled CRT display. © 1999 John Wiley & Sons, Inc. Col Res Appl, 24, 164–176, 1999