Abstract: A method for freely selectable substitution of the achromatic part in multi-color printing with the black ink on the basis of a spectrally photometrically scanned original, whereby supporting points in the color space are acquired in the spectrally photometric scanning of the original. Corresponding to a preselected degree, the achromatic part or the complementary color part of the colors of a printing color space constructed multi-color are replaced by the black ink. Supporting point data are photometrically acquired from a color scale specifically associated to a printing process. The printing color space is classified into a color model that is independent of a printing color (HSL Model, FIG. 1) and is displayed in this model. A two-dimensional, non-linear deepening field is formed with luminance values (FIG. 2) and a two-dimensional, non-linear desaturation field is formed with saturation values (FIG.