Details:
Summary:
The acceptance of color variations in picture printing is to a great extent determined by picture contrast. Neither density values nor spectrophotometrical values can be used for the description of perceptible color shifts. Pictures are classified in the System Brunner Picture Contrast Profile (PCP) in four classes, according to their contrast profile. For the presentation of color gradations in the picture, the changes are measured in a gray balance patch, representative of all screened pictures, using a special densitometer, and from there area coverage and dot gain are determined. The hue in the System Brunner Color Balance Hexagon is calculated from the three difference pairs of the dot gain values of cyan-magenta, cyan-yellow, and magenta-yellow. The Hexagon is structurally based on the Munsell system. Instead of Munsell units, differences in area coverage by screen dots are used as measuring units.