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Surface color perception under two illuminants: the second illuminant reduces color constancyThis study investigates color perception in a scene with two different illuminants. The two illuminants, in opposite corners, simultaneously shine on a (simulated) scene with an opaque dividing wall, which controls how much of the scene is illuminated by each source. In the first experiment, the height of the dividing wall was varied. This changed the amount of each illuminant reaching objects on the opposite side of the wall. Results showed that the degree of color constancy decreased when a region on one side of the wall had cues to both illuminants, suggesting that cues from the second illuminant are detrimental to color constancy. In a later experiment, color constancy was found to improve when the specular highlight cues from the second illuminant were altered to be consistent with the first illuminant. This corroborates the influence of specular highlights in surface color perception, and suggests that the reduced color constancy in the first experiment is due to the inconsistent, though physically correct, cues from the two illuminants.
Document ID
Document Type
Reprint (Version printed in journal)
Yang, Joong Nam (University of Chicago Chicago, IL, United States)
Shevell, Steven K.
Date Acquired
August 21, 2013
Publication Date
January 1, 2003
Publication Information
Publication: Journal of vision (Charlottesville, Va.)
Volume: 3
Issue: 5
Subject Category
Life Sciences (General)
Funding Number(s)
Distribution Limits