Chromostereopsis and chromatic dispersion.

Slits placed before the eyes measured the chromatic dispersion of the eyes as a function of the separation of the slits. Prisms in front of the eyes determined the separation of the visual and null axes. The product of these separate measurements predicted the apparent depth expected with full-pupil stereoscopy. Agreement was good suggesting that chromostereopsis depends primarily on dispersion. The pupils were important modulators; a term for the Stiles-Crawford effect was not needed. Theoretical calculations to predict the effects of dispersion by slits and prisms agreed with experiments.