Munsell system describing color

Figure F5.1.1 The Munsell system describes color in terms of hue, value, and chroma. Figure courtesy of GretagMacbeth. This black and white facsimile of the figure is intended only as a placeholder for full-color version of figure go to http //www.currentprotocols.com/colorfigures...

One of the best known color classification systems is that of Munsell which was devised in the early part of this century. The System relies on three attributes of color hue, chroma, and value. Hue refers to the color quality that is described by words like red, blue, and green in other words, the name of the color. Chroma is used to describe the purity or saturation of a color. It may be thought of as how dirty or clean a color is perceived to be. Value is the color term which we use to describe how light or dark a color is. The Munsell system plots color on a three-dimensional coordinate system in which the vertical axis represents value and the radial axis represents chroma. The various hues are arranged around the periphery of the three-dimensional solid. The Munsell Book of Color is a compilation of some 1500 painted paper chips which allow for comparison with a sample color. Approximately 100,000 colors can be distinguished in the Munsell system by interpolation [15]. A color representation of the Munsell system can be found in the books by Billmeyer and Saltzman [6], Overheim and Wagner [11], and Hunt [14] or on the Munsell homepage [16]. 

In contrast to the Munsell system, the CIE system does not use color samples. The CIE system is based on the Grassmann laws, which state that a color valency is completely described by the sum of the vector products of three color values and their color value proportions ... 

Color notion n. Orderly system of numbers, letters, or a combination of both, which serves to describe the relationship of colors in three-dimensional space. Thus, three dimensions must be included for example, hue, value, and chroma of the Munsell System. Single dimensional notations, such as a yellowness sale, can be used only if the other two dimensions are fixed or described two-dimensional notations can be used only if the third is fixed or described. See color order systems. 

Color order systems n. Systems used to describe an orderly three-dimensional arrangement of colors. Three bases can be used for ordering colors (1) an appearance basis, i.e., a psychological basis in terms of hue, saturation, and lightness - an example is the Munsell System (2) an orderly additive color mixture basis, i.e., a psychophysical basis - examples are the CIE System and the Ostwald System and (3) an orderly subtractive color mixture basis - an example is the Plochere Color System, based on an orderly mixture of inks. 

Sanderson-Milner zeta space color difference equation n. A color difference equation designed to fit the spacing of the Munsell system and based on Munsell value functions as described in the Adams chromatic value color difference equation ... 

The Munsell color system is conceptually similar to the QELAB system, but with some significant differences. The Munsell system was conceived by the American painter Albert H. MunseU in 1905 with subsequent revisions and variations. The three variables used to describe colors in the system are hue, brightness (similar to lightness in QELAB), and saturation (similar to chroma also called value). As shown in Figure 11.14, the color space is cylindrical. The hue is divided into 100 equal spaces around the circle that forms the cross section of the cylinder, while the y direction is the brightness, scaled from 0 to 18. The x-axis is the saturation, scaled from 10 to 18. Munsell charts and collections are used in the forensic analysis of paints and soils. Because books and samples of color are used for color comparison, the Munsell color space is sometimes referred to as a catalog system. An example application is in soil analysis in which soil particles can be seived, sorted, and grouped by their Munsell color. 

There are several such systems in common use, of which only one, the Munsell system, will be described here. In this system, the vertical lightness axis is said to vary in value (equivalent to lightness) from 0 (black) to 10 (white). At any given value level, colors are arranged as described... 

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