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Updated: Aug 21, 2026

Visualizing Visual Adaptation
Published on: April 24, 2017
Protanopic observers show nearly normal color constancy with natural reflectance spectra
Rigmor C Baraas1, David H Foster, Kinjiro Amano
1Visual and Computational Neuroscience Group, University of Manchester Institute of Science and Technology, Manchester, UK. r.baraas@umist.ac.uk
Abstract:
The ability of color-deficient observers to discriminate between illuminant changes and surface-reflectance changes in a scene was tested with natural and Munsell reflectance spectra. To avoid the confounding effects of spatial structure, stimuli were simulations of Mondrian-like colored patterns, presented on a computer-controlled color monitor. Protanopes performed less well than normal trichromats, regardless of the type of reflectance spectra, but they were least disadvantaged with patterns comprising reflectance spectra drawn from urban and rural scenes, more characteristic of the natural environment.
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