Philosophy of perceptive color order systems

A color order system may arrange color perceptions, color stimuli, or material color samples according to certain rules. Material color systems have many practical applications but are different for different materials and different applications. Stimulus systems are useful in comparing instrumental measurements of transmitted or reflected radiation, but do not adequately describe the appearance of the color perceptions. In most perceptive color systems attributes like hue, saturation, and lightness (or their near correlates) describe three‐dimensional color space. There are two main exceptions: the OSA–UCS system intended to be equidistant in all directions of color space, and the NCS, which is a Hering‐type opponent system, based on six innate elementary colors with six corresponding attributes. In the NCS, hue and chromaticness, which in other systems are primary attributes, are derived from the elementary attributes.