Nature of variations in normal color matches

Abstract

Although there is a considerable body of evidence from color matching to suggest that there are reliable variations in the spectral positioning of the M and L cone pigments among normal trichromats, both the magnitude of the variation and its distributional nature are still matters of concern. Earlier we found discrete variation in color matching among normals and interpreted that result as indicating a discrete variation in the spectra of the underlying cone pigments. Recently, Jordan and Mollon (ARVO, 1988) reported on a color matching experiment in which they attempted to check our result. They failed to find discrete variation in color matching. Since their experiment differed from ours in several procedural details, we ran a new experiment incorporating these differences. The results again reveal discrete variations in color matching among color normals. We also obtained two different color matches from each of sixty subjects. Comparisons of the matches allow one to eliminate the possibility that the differences between groups of normals arise from mechanisms other than variations in the spectra of the cone pigments.