Describing natural colors with Munsell and NCS color systems

Abstract

The Munsell Color System and the Natural Color System are widely used but they have some limitations due to the manufacturing process and sampling choices. To estimate quantitatively these limitations we compared the colors of natural scenes with the colors represented by these systems under a wide range of illuminants. Spectral data from the two systems and from natural scenes were used in the analysis. It was found that a considerable portion of natural colors are not accounted by these systems, mainly colors with low lightness levels. Under D65 the Munsell Color System color volume corresponds to 72% of the Natural Color System color volume which in turn represents only 53% of the natural scenes color volume. If individual colors are considered, less than half are contained within these systems. To obtain a complete match to the natural colors contained by the color systems thresholds of 7 and 5 CIELAB units would be required for Munsell Color System and Natural Color System, respectively. Variations with the illuminant are generally modest showing that both system work similarly across different illuminations. Although these Color Systems have limitations in describing low lightness colors they perform quite well for medium to high levels of lightness.

Red, yellow, green, and blue are not particularly colorful

“…However, these peaks were due to sampling stimuli from the set of maximally saturated Munsell chips. The limits of maximal saturation in the Munsell system are at least partially due to pigments and do not necessarily reflect properties of the perceptual system (Pastilha, Linhares, Rodrigues, & Nascimento, 2019;cf. figure 4 in Witzel, 2018b).…”

Colour Preferences and Personality Traits

“…We used the Natural Colour System [36] to register primary colours. That system is widely used both among various professions and researchers [37][38][39]. In the current project we used only the basic colours of which there are six: the two achromatic colours black and white, and four chromatic colours: yellow, red, blue, and green (see fig.…”

Sensory representation of surface reflectances assessments

“…Professionals at different levels of a supply chain might neither have the expertise nor the instruments to measure, compute, and communicate reflectance and illuminant spectra. Indeed, most producers of pigments, dyes, coloured objects and materials rely on coordinates in colour appearance spaces (e.g., CIELAB, CIELUV, CIECAM02 etc., for review, see [1,2]) or comparisons with reference surfaces under reference lighting (e.g., Munsell, Pantone etc., [11][12][13]). These widely used practical approaches are not only subjective, ad hoc, and approximate; they also miss the problem of metamer mismatching; imposing limitations on the accuracy of these models [9].…”