Abstract A method of producing colored reproductions of colored originals, utilizing electronic color correction, in which a secondary correction signal which disappears for gray tones is formed from the uncorrected color separation signals and another signal of the same gray contrast containing color correction information, by formation of the difference, in which the primary color separation signals concerned, proportional to the transparency, are transformed according to a nonlinear function which is a monotonic intermediate function between a linear and a logarithmic function, and the course of which in the region between 100 percent and 1 percent of the white signal value is represented by a power function y xa in which 0.3 a 0.6. Preferably a Munsell function.
A method of producing colored reproductions of colored originals, utilizing electronic color correction, in which a secondary correction signal, which disappears for gray tones, is formed from the uncorrected color separation and another signal of the same gray contrast containing color correction information, by forming the difference, comprising the step of transforming the primary color separation signals concerned, which are proportional to the transparency, according to a nonlinear function which is a monotonic intermediate function between a linear and a logarithmic function, and the course of which in the region between 100 percent and 1 percent of the white signal value is represented by a power function y xa with 0.3 a 0.6, and thereafter forming such difference signal from the transformed separation signals involved.
Claim 2
Independent Claim
125 words
A method of producing colored reproductions of colored originals, utilizing electronic color correction, in which a secondary correction signal, which disappears for gray tones, is formed from the uncorrected color separation and another signal of the same gray contrast containing color correction information, by forming the difference, comprising the step of transforming the primary color separation signals concerned, which are proportional to the transparency, according to a nonlinear function which is a monotonic intermediate function between a linear and a logarithmic function, and the course of which in the region between 100 percent and 1 percent of the white signal value is represented by a power function y xa with 0.3 a 0.6, and thereafter forming such difference signal from the transformed separation signals involved.
Claim 3
Dependent Claim
29 words
A method according to claim 1, wherein the function according to which the color separation signals are transformed, is a Munsell function (function or like physiological differences of perception).