Patent ID: 6873433

Claim:
A method of calibrating a color reproduction apparatus which has a process for converting received digital color signals to uniquely-associated drive code values and to then produce an image rendering with color densities corresponding to the drive code values, the method comprising the steps of: using the color reproduction apparatus to produce a calibration target having a plurality of color patches by using input code values which correspond to a sampling of color densities, wherein one subset of said color patches is intended to have neutral color density values and another subset of said color patches is intended to have non-neutral color density values deviating in their mix of red, green, and blue from each other; measuring color densities of the color patches produced on said calibration target; producing error signals characteristic of differences between measured color densities and intended color densities of (1) the patches intended to have neutral density values and (2) the patches intended to have non-neutral density values; and adjusting the converting process of said reproduction apparatus as a function of said error signals so as to provide output color densities closer to the intended color densities.