Patent ID: 8537420

Claim:
A method for correcting the gray balance of a printing process, in which printing forms allocated to color separations are imaged with at least one test form, the method comprising the following steps: printing at least one printing material in a printing press with the printing forms, using at least three colored printing inks and a black printing ink; colorimetrically measuring the test form printed onto the printing material, with the test form including at least one gray balance area having a chromatic gray area and a black area and the chromatic gray area being formed from the colored printing inks in accordance with a first tonal value combination; providing the first tonal values of the chromatic inks in the combination according to a first predefined color profile with the same intended color value as the black area; creating the first predefined color profile in accordance with a predefined first printing condition of a predefined printing process following a first process calibration; determining actual color values of the black area and of the chromatic gray area of the at least one gray balance area; determining a second tonal value combination of the printing inks in accordance with the first predefined color profile by using the actual color value of the black area; determining a third tonal value combination of the printing inks in accordance with the first predefined color profile by using the actual color value of the chromatic gray area; determining first measured values of the first predefined process calibration corresponding to predefined tonal values, while taking the first printing condition into account; determining corrected measured values for at least a part of the first measured values, by using the second and third tonal value combinations; replacing at least the part of the first measured values with the corrected measured values; and carrying out a second process calibration by using the corrected measured values and taking the printing condition of the predefined printing process into account, and imaging printing forms in an imaging process according to the second process calibration for a substantially identical printing condition.