In colorimetry, the Munsell color method is a color space that specifies colors according to three color dimensions: hue, value (lightness), and chroma (color purity). It was actually created by Professor Albert H. Munsell within the first decade of the twentieth century and adopted by the USDA as being the official color system for soil research in the 1930s.
Several earlier color order systems had placed colors into a three-dimensional color solid of merely one form or another, but Munsell was the first one to separate hue, value, and chroma into perceptually uniform and independent dimensions, and he was the first to systematically illustrate the colours in three-dimensional space. Munsell’s system, especially the later renotations, is based on rigorous measurements of human subjects’ visual responses to color, putting it on a firm experimental scientific basis. As a result basis in human visual perception, Munsell’s system has outlasted its contemporary color models, despite the fact that it really has been superseded for some uses by models like CIELAB (L*a*b*) and CIECAM02, it really is still in wide use today.
Munsell’s color sphere, 1900. Later, munsell soil color chart found out that if hue, value, and chroma were to be kept perceptually uniform, achievable surface colors could not be forced into a regular shape.
Three-dimensional representation in the 1943 Munsell renotations. Notice the irregularity from the shape in comparison with Munsell’s earlier color sphere, at left.
The system is made up of three independent dimensions which is often represented cylindrically in three dimensions for an irregular color solid: hue, measured by degrees around horizontal circles; chroma, measured radially outward in the neutral (gray) vertical axis; and value, measured vertically from (black) to 10 (white). Munsell determined the spacing of colors along these dimensions by taking measurements of human visual responses. In each dimension, Munsell colors are as close to perceptually uniform as he could make them, helping to make the resulting shape quite irregular. As Munsell explains:
Desire to fit a chosen contour, like the pyramid, cone, cylinder or cube, in conjunction with not enough proper tests, has triggered many distorted statements of color relations, and it also becomes evident, when physical measurement of pigment values and chromas is studied, that no regular contour will serve.
-?Albert H. Munsell, “A Pigment Color System and Notation”
Each horizontal circle Munsell separated into five principal hues: Red, Yellow, Green, Blue, and Purple, along with 5 intermediate hues (e.g., YR) halfway between adjacent principal hues. Each one of these 10 steps, together with the named hue given number 5, will then be broken into 10 sub-steps, in order that 100 hues receive integer values. In reality, color charts conventionally specify 40 hues, in increments of 2.5, progressing in terms of example 10R to 2.5YR.
Two colors of equal value and chroma, on opposite sides of your hue circle, are complementary colors, and mix additively towards the neutral gray the exact same value. The diagram below shows 40 evenly spaced Munsell hues, with complements vertically aligned.
Value, or lightness, varies vertically across the color solid, from black (value ) in the bottom, to white (value 10) on the top.Neutral grays lie across the vertical axis between white and black.
Several color solids before Munsell’s plotted luminosity from black at the base to white on the top, using a gray gradient between the two, however these systems neglected to maintain perceptual lightness constant across horizontal slices. Instead, they plotted fully saturated yellow (light), and fully saturated blue and purple (dark) along the equator.
Chroma, measured radially from the center of each slice, represents the “purity” of your color (linked to saturation), with lower chroma being less pure (more washed out, like pastels). Keep in mind that there is no intrinsic upper limit to chroma. Different regions of the colour space have different maximal chroma coordinates. For instance light yellow colors have significantly more potential chroma than light purples, because of the nature in the eye as well as the physics of color stimuli. This led to an array of possible chroma levels-around our prime 30s for many hue-value combinations (though it is not easy or impossible to make physical objects in colors of these high chromas, plus they should not be reproduced on current computer displays). Vivid solid colors have been in the range of approximately 8.
Keep in mind that the Munsell Book of Color contains more color samples than this chart for 5PB and 5Y (particularly bright yellows, up to 5Y 8.5/14). However, they are not reproducible in the sRGB color space, which has a limited color gamut designed to match that of televisions and computer displays. Note additionally that there 85dexupky no samples for values (pure black) and 10 (pure white), that happen to be theoretical limits not reachable in pigment, with out printed examples of value 1..
A color is fully specified by listing the three numbers for hue, value, and chroma in that order. As an example, a purple of medium lightness and fairly saturated could be 5P 5/10 with 5P meaning colour during the purple hue band, 5/ meaning medium value (lightness), as well as a chroma of 10 (see swatch).
The notion of by using a three-dimensional color solid to represent all colors was made through the 18th and 19th centuries. A number of different shapes for this sort of solid were proposed, including: a double triangular pyramid by Tobias Mayer in 1758, a single triangular pyramid by Johann Heinrich Lambert in 1772, a sphere by Philipp Otto Runge in 1810, a hemisphere by Michel Eugène Chevreul in 1839, a cone by Hermann von Helmholtz in 1860, a tilted cube by William Benson in 1868, plus a slanted double cone by August Kirschmann in 1895. These systems became progressively more sophisticated, with Kirschmann’s even recognizing the visible difference in value between bright colors of different hues. But all of them remained either purely theoretical or encountered practical problems in accommodating all colors. Furthermore, none was based on any rigorous scientific measurement of human vision; before Munsell, the relationship between hue, value, and chroma was not understood.
Albert Munsell, an artist and professor of art in the Massachusetts Normal Art School (now Massachusetts College of Art and Design, or MassArt), wanted to produce a “rational method to describe color” that will use decimal notation as an alternative to color names (which he felt were “foolish” and “misleading”), which he can use to teach his students about color. He first started work with the program in 1898 and published it 100 % form in A Color Notation in 1905.
The initial embodiment of your system (the 1905 Atlas) had some deficiencies as being a physical representation from the theoretical system. They were improved significantly within the 1929 Munsell Book of Color and through a comprehensive series of experiments carried out by the Optical Society of America in the 1940s leading to the notations (sample definitions) to the modern Munsell Book of Color. Though several replacements for your Munsell system have already been invented, building on Munsell’s foundational ideas-including the Optical Society of America’s Uniform Color Scales, and also the International Commission on Illumination’s CIELAB and CIECAM02 color models-the Munsell method is still commonly used, by, and the like, ANSI to define hair and skin colors for forensic pathology, the USGS for matching soil colors, in prosthodontics during selecting shades for dental restorations, and breweries for matching beer colors.