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Updated: May 29, 2026
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Visualizing Visual Adaptation
Published on: April 24, 2017
Colour constancy as measured by least dissimilar matching.
Alexander D Logvinenko1, Rumi Tokunaga
1Department of Vision Sciences, Glasgow Caledonian University, Cowcaddens Road, Glasgow G4 0BA, UK. a.longvinenko@gcu.ac.uk
Seeing and Perceiving
|September 10, 2011
Summary
Achieving exact color matches under different lighting is impossible. This study found that while least dissimilar matching is systematic, color constancy fails for many objects due to metamer mismatching, suggesting an evolutionary trade-off.
Area of Science:
- Visual Perception
- Color Science
- Psychophysics
Background:
- Asymmetric color matching is a common experimental technique for studying color constancy.
- Exact color matches between objects under different chromatic illuminations are typically unachievable.
Purpose of the Study:
- To investigate the effectiveness of "least dissimilar matching" as a method for assessing color perception under varying illuminations.
- To evaluate the extent of color constancy and identify factors influencing its success or failure.
Main Methods:
- Four trichromatic observers performed "least dissimilar matching" with two sets of 22 Munsell papers under independent neutral, yellow, blue, green, and red illuminations.
- The proportion of exact matches was recorded under various illumination conditions (same light, one neutral/one chromatic, both chromatic).
Main Results:
- Exact match rates were high under identical lighting but significantly decreased under chromatic or mismatched illuminations.
- Least dissimilar matching demonstrated systematic properties (symmetric, transitive) but varied considerably across different Munsell papers.
- Exact match rates ranged from 0.99 for black to 0.12 for purple paper, indicating object-specific constancy failures.
Conclusions:
- Color constancy is not universally achieved for all reflecting objects, primarily due to metamer mismatching under different illuminations.
- The visual system may prioritize color constancy for ecologically relevant objects, potentially at the expense of inconstancy for others.
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