Effects of colored lights, spacing between stimuli, and viewing distance on error in a depth-matching task

A previous study indicated that color of a comparison stimulus, colored light, and illumination significantly affected the error in perceived depth with binocular and monocular vision. Here, the effects of spacing between standard and comparison stimuli, viewing distance, and five colored lights were investigated. 32 Taiwanese university students in five groups were assigned to one of five colored light conditions. Spacing between comparison and standard stimuli significantly affected error in a depth-matching task. Errors increased with increased spacing. Colored light also had a significant effect; error rate in the depth-matching task under the green light condition was significantly greater than the rates under the white, yellow, and red light conditions, but the difference in error rates between blue and green and among the white, yellow, and red light conditions were not significant. The error rate at a viewing distance of 110 cm was significantly less than errors under 70- and 150-cm conditions. In addition, a two-way interaction effect was detected: viewing distance with spacing between standard and comparison stimuli.