All Effects of Psychophysical Variables on Color Attributes: A Classification System Pridmore, Ralph W. Melgosa Latorre, Manuel Classification system Psychophysical variables Color attributes This paper reports the research and structuring of a classification system for the effects of psychophysical variables on the color attributes. A basic role of color science is to psychophysically specify color appearance. An early stage is to specify the effects of the psychophysical variables (as singles, pairs, etc) on the color attributes (as singles, pairs, etc), for example to model color appearance. Current data on effects are often scarce or conflicting. Few effects are well understood, and the practice of naming effects after their discoverer(s) is inadequate and can be confusing. The number and types of possible effects have never been systematically analyzed and categorized. We propose a simple and rigorous system of classification including nomenclature. The total range of effects is computed from the possible combinations of three psychophysical variables (luminance, dominant wavelength, purity) and six color attributes (lightness, brightness, hue, chroma, colorfulness, saturation) in all modes of appearance. Omitting those effects that are normally impossible to perceive at any one time (such as four- or five-dimensional colors), the total number perceivable is 161 types of effects for all modes of appearance. The type of effect is named after the psychophysical stimulus (or stimuli) and the relevant color attribute(s), e.g., Luminance-on-hue effect (traditionally known as Bezold-Brucke effect). Each type of effect may include slightly different effects with infinite variations depending on experimental parameters. 2015-04-21T11:33:41Z 2015-04-21T11:33:41Z 2015 info:eu-repo/semantics/article Pridmore, R.W.; Melgosa Latorre, M. All Effects of Psychophysical Variables on Color Attributes: A Classification System. Plos One, 10(4): e0119024 (2015). [http://hdl.handle.net/10481/35750] 1932-6203 http://hdl.handle.net/10481/35750 10.1371/journal.pone.0119024 eng info:eu-repo/semantics/openAccess Public Library of Science (PLOS)