Flicker between equal-luminance colors examined with multidimensional scaling.
Even when two rapidly alternating color stimuli are equated in luminance, the flicker between them is not always zero. By one hypothesis this residual chromatic flicker is tritanopic, like edge distinctness: dependent purely on L- and M-cone stimulation, with no contribution from S-cones. Judgments of flicker intensity between pairs of colors were analyzed with multidimensional scaling (MDS)--in effect treating them as an index of color dissimilarity. They reveal a systematic reduction of flicker when stimulus pairs differ along a chartreuse-magenta direction in the color plane, corresponding to an effective compression of color space along this axis or an equivalent elongation along a blue-orange axis. In contrast, judgments of edge distinctness between the same pairs reveal the expected tritanopic axis of compression. It follows that chromatic flicker does receive a contribution from S-cone stimulation, but this interacts with the contribution from L- and M-cones, perhaps due to phase delays.
Bimler
David
D
Department of Health and Human Development, Massey University, Private Bag 11-222, Palmerston North, New Zealand. d.bimler@massey.ac.nz
D000465:Algorithms; D016477:Artifacts; D003119:Color Perception Tests / Q000379:methods*; D003124:Colorimetry / Q000379:methods*; D003198:Computer Simulation; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008962:Models, Theoretical; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity