The concept of color space has come to be an unquestioned three-dimensional representation of color stimuli, or color appearance, intended to simplify the relationships among physically measurable attributes of light, mathematical formulae, and human sensations and perceptions. The notion of three-dimensional mathematical spaces as adjuncts for color is often helpful, but perhaps also misleading at times. Color appearance models requiring five or six dimensions to represent color appearance illustrate some of the limitations of historic spaces. This paper poses the question of whether color appearance would be better represented by independent appearance scales with no requirement that they be related as a higher-dimensional space. In other words, is color better represented by six one-dimensional color scales than one or two three-dimensional color spaces. A framework for implementing such appearance scales is described and one implementation is presented along with discussion of the ramifications for color difference metrics.
Mark D. Fairchild, Rodney L. Heckaman, "Deriving Appearance Scales" in Proc. IS&T 20th Color and Imaging Conf., 2012, pp 281 - 286, https://doi.org/10.2352/CIC.2012.20.1.art00050