Bezold–Brücke Hue Shift Measured by Color-Naming Technique*

Three experiments on the Bezold–Brucke phenomenon (change in the hue of spectral colors caused by change in field luminance) are reported. The first is an exact replication of Purdy’s classic experiment, where the shift between 100 and 1000 trolands is investigated by direct matching in a steadily presented bipartite field. The second is a modification of Purdy’s experiment where the observer is asked to match on the basis of 300-msec flashes of the bipartite field. The third is an experiment where no matches are required, but where the observer is asked to judge the hue of a flashing stimulus using a forced-choice color-naming technique. The results of the three experiments are compared: differences are discussed in terms of viewing time and simultaneous contrast.