Interindividual receptor variability of normal colour observers: analysis of the 2-deg Stiles and Burch data

Examination of the interobserver variability among the ten observers of the 2-deg Stiles and Burch colorimetric study reveals an interesting pattern: the chromaticities of the matches made by different normal subjects fall approximately on straight lines and these lines appear to converge. Because of a geometric relationship that holds between the normal, anomalous, and dichromatic colour spaces, it can be argued that part of the variability must be due to actual differences in the shape or spectral position of the receptor sensitivities of different normal observers.