Related Experiment Video
Updated: Jul 20, 2026

Visualizing Visual Adaptation
Published on: April 24, 2017
Anomalous trichromats' judgments of surface color in natural scenes under different daylights
Rigmor C Baraas1, David H Foster, Kinjiro Amano
1Department of Optometry & Visual Science, Buskerud University College, Norway. rigmor.baraas@hibu.no
Abstract:
Deuteranomalous trichromacy, which affects medium-wavelength-sensitive cones, is more common than protanomalous trichromacy, which affects long-wavelength-sensitive cones. The aim of the present work was to test the extent to which these two kinds of anomalous trichromacy affect surface-color judgments in the natural world. Simulations of 18 natural scenes under different daylight illuminants were presented on a high-resolution color monitor to 7 deuteranomalous, 7 protanomalous, and 12 normal trichromatic observers, who had to discriminate between reflectance and illuminant changes in the images. Observers' ability to judge surface color was quantified by a standard color-constancy index. Deuteranomalous trichromats performed as well as normal trichromats, but protanomalous trichromats performed more poorly than both. The results are considered in relation to the spectral coverage of cones, rod intrusion, and the characterization of anomalous trichromacy by the Rayleigh match.
Related Concept Videos
Photoreceptors and Visual Pathways
Color Vision
Perceptual Constancy
Size constancy is the recognition that an object remains the same size, even when its image on the retina changes. For instance, a bus is perceived to be large enough to carry people, even if it looks tiny from...
Photoreceptors and Plant Responses to Light
Anatomy of the Eyeball
Changes in Skin Color: Clinical Perspectives
Albinism
Albinism is a genetic disorder that affects (completely or partially) the coloring of skin, hair, and eyes. The defect is primarily...

