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Updated: Jun 8, 2026
11:57
Measuring Spatially- and Directionally-varying Light Scattering from Biological Material
Published on: May 20, 2013
Material and lighting hues of object colour
Rumi Tokunaga1, Alexander D Logvinenko
1Department of Vision Sciences, Glasgow Caledonian University, City Campus, Cowcaddens Road, Glasgow, UK. rumi.tokunaga@riec.tohoku.ac.jp
Summary
Perceptual color models struggle to distinguish material and lighting hues. This study shows observers can differentiate these, revealing a distinct yellow-blue lighting dimension in perception.
Area of Science:
- * Visual perception and color science.
- * Investigating human observers' ability to distinguish between material and lighting color properties.
Background:
- * Current color appearance models do not account for the perceptual difference between material hues (e.g., stains) and lighting hues (e.g., shadows).
- * This distinction is readily apparent to human observers, even those without specialized training.
Purpose of the Study:
- * To provide experimental evidence for the dissociation of material and lighting hues in human perceptual space.
- * To investigate the underlying dimensions of this perceptual separation.
Main Methods:
- * Experiment using Munsell papers under independent yellow, neutral, and blue illumination.
- * Five trichromatic observers ranked dissimilarities between paper/light combinations.
- * Non-metric multidimensional scaling (MDS) analysis of observer data.
Main Results:
- * MDS revealed distinct configurations for papers under different lights, maintaining their original order.
- * Configurations under yellow and blue light shifted parallel to each other, with neutral light in between.
- * This shift indicates a perceptual yellow-blue lighting dimension.
Conclusions:
- * Human perception dissociates material and lighting hues, a finding not captured by existing models.
- * A distinct yellow-blue lighting dimension exists in perceptual space.
- * This lighting dimension is independent of the reflected light properties.
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