Munsell chart

Chroma, which is a measure of the saturation of the colour, is expressed by the distance from the value axis. A typical plane in the Munsell chart is shown in Fig. 26.8, in which the hue 5Y (yellow) is illustrated in various values and graduations of chroma on the right of the central black/ white axis. On the left of the same axis the hue 5PB (purple-blue) is treated in the same manner. The individual colours are identified according to their positions and that represented by.the square marked X would be designated as 5Y8/4 the hue being followed by the value number and separated by a stroke from the chroma number. 

The Munsell chart and Ostwald s system are not all that might be desired because their construction and use are not free from subjective elements they have other limitations such as lack of permanency of the colour standards. In 1931 the Commission Internationale de I Eclairage, usually referred to as the C.I.E., recommended what is known as the C.I.E.. system for numerical specification of colour. The foundation on which the method was based was the colour triangle illustrated in Fig. 26.9. It is assumed that the corners of an equilateral triangle are illuminated by the... 

Moist and crushed, according to the Munsell charts. c=clay, si=silt or silty, l=loam. l=weak, 2=moderate, 3=strong th= cr=crumb, abk=angular blocky, sbk=subangular blocky, pl=platy —> breaking into. m=moist, fr=friable, fi=firm w=wet, plastic. 7 0=absent, Vj=very few, 1 =few, 2=plentiful, 3=abundant mi=micro, vf=very fine, f=fine, m=medium, co=coarse. at naked eyes. 0=absent, +=few, + + =plentiful, + + + = abundant. a=abrupt, c=clear s=smooth, w=wavy, b=broken. 

Munsell charts Standard color reference charts taken from the Munsell soil color scheme where the hne and chroma of a color are given. 

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. 

Methods are described for determining the extent to which original natural color is preserved in processing and subsequent storage of foods. Color differences may be evaluated indirectly in terms of some physical characteristic of the sample or extracted fraction thereof that is largely responsible for the color characteristics. For evaluation more directly in terms of what the observer actually sees, color differences are measured by reflectance spectrophotometry and photoelectric colorimetry and expressed as differences in psychophysical indexes such as luminous reflectance and chromaticity. The reflectance spectro-photometric method provides time-constant records in research investigation on foods, while photoelectric colorimeters and reflectometers may prove useful in industrial color applications. Psychophysical notation may be converted by standard methods to the colorimetrically more descriptive terms of Munsell hue, value, and chroma. Here color charts are useful for a direct evaluation of results. 

Conversion tables and charts now available make it possible to express I.C.I. data in forms in which a specified color and the significance of measured color differences can be more easily visualized. For example, I.C.I. values calculated from objective instrumental readings can be converted into the Munsell notation which evaluates the three psychological color attributes—hue, lightness (Munsell value), saturation (Munsell chroma)—on scales of approximately equal visual steps. In addition, the Munsell color charts offer one of the most convenient sources of material standards for direct color comparisons. 

If results of color measurements are expressed in Munsell notation, a reader can use Munsell color charts as an aid in visualizing approximate ranges of color differences involved. Such a means has been suggested (15) for expressing color of light-colored juices. The necessary experimental data were obtained with a reflection meter similar to the reflectometer described. 

It is desirable for the record to have an objective statement of the nature and degree of color deterioration. The simplest, but least desirable, method is comparison of sample color with color charts or plates such as those used in the Munsell system, Ridgeway s color standards, or the Maerz and Paul dictionary of color. Such a method is limited in value because of the difficulty of obtaining true color matches, and because of variations due to human error. The use of color charts or plates may be much improved in the Munsell system by employing a disk colorimeter (29). Kramer and Smith (21) have pointed out that the results obtained in its application to foods are sometimes difficult to explain and compare, and that the method requires special training of the operator and is tedious and cumbersome. 

In an extension of their work, Goodhart and coworkers developed a system [45] whereby the final desired color of a compressed table formulation was first chosen from a standard color chart (such as the Munsell compilation [40]). This color was then analyzed as to its CIE parameters, and these parameters were in turn used to develop a colorant combination that would produce a match of the desired color. The ultimate end of this work was to produce a database of sufficient depth that the empirical nature of color matching could be eliminated. 

The typical Munsell color chart for soils covers only those colors described as being yellow or red or some combination of the two. This is not to say that... 

Munsell Soil Color Charts. Baltimore, MD Kollmorgen Corporation 1975. 

Color is important in all forms of potato products, boiled, baked, fried, and chipped. Where a limited number of broad classifications are used, as in some commercial processing situations, use is made of visual reference charts showing a limited range of colors. Such charts are available for French fiies (Munsell USDA Frozen French Fry Standard, X-Rite Right On Colour) and for potato chips (Colour Standards Reference Chart for Potato Chips, Snack Food Association). 

In particular, soil color should be determined on dry and moist samples using Munsell Soil Color Charts (1994). Soil color is usually the first property recorded in a morphological description of soils (and may be the only feature of significance to a layperson) and provides an indicator of redox status because soil color relates to soil aeration and organic matter content (Fitzpatrick, McKenzie, and Maschmedt 1999). Soil color has been found to be extremely useful in forensic soil identification by Sugita and Marumo (1996). 

Munsell Soil Color Charts (1994). Munsell Color. New Windsor, NY Macbeth Division of Kollinorgen Instruments Corporation. 

We have used two techniques in an attempt to compare the "color" of the various adsorbents. First, they have been compared with Munsell soil color charts (17). Second, their diffuse reflectance spectra have been measured (vs. white filter paper as reference). These results are summarized in Tables III and IV, respectively. 

Munsell Soil Color Charts Kollmorgen Corp. Baltimore, 1975. 

Color is a problem for scientific study. One aspect is the vocabulary one used to describe color. Mint green, bottle green, and Kelly green are nice names but not of great utility in that people s physical perception of color is not always the same. In some industries, such as colored fabric manufacture, current use is to send a set of standard colors which are matched by the producer. This is similar to the use of the Munsell color charts in geology. None of these processes makes use of physical optical spectral studies. The reason is that they are difficult to obtain and interpret. For a geologist, color is very important but we rarely have the possibility to standardize the method of our color perception. One reason is that color is both a reflective and transmission phenomenon. The thickness of the sample is critical to any transmission characteristics. Hence, a field color determination is different from one... 

Color Charts. The colors of pigments can be routinely measured by visual comparison with color charts like the one issued by the Munsell Color Company. This method may achieve a high precision because of the eye s sensitivity to small (relative) color changes. Of paramount importance for reliable application is a uniform light source. The major drawback of the method is that the resolution of color assignments is limited by the resolution of the color chips (see 3.2.3). Interpolation between chips is possible in principle, but difficult in practice as it has to be done in a three-dimensional space. 

Use a tape measure to allow the recording of depths and hence the thicknesses of the soil horizons in the profile. Colour is used to identify the different horizons within the profile. Standardized descriptions of colour can be obtained by the use of the Munsell Soil Colour Chart System (see Chapter 1). 

The following are Munsell notations and Commission Internationale de L Eclariage (CIE) coordinates which describe the Office of Hazardous Materials Regulation Label and Placard Color Tolerance Charts in Tables 1 and 2, and the CIE coordinates for... 

For the visual assessment of a color, a reference sample is needed. Systems of physical color samples are available for reference purposes, such as the Munsell system, DIN color chart. Natural Color System and the more customized RAL and Pantone color charts. The ISO grey scale is defined for the visual assessment of color differences and used for the specification of color tolerances for quality control purposes. 

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