One embodiment of a method for calibrating a test color measurement device in conjunction with an emissive display includes measuring spectral sensitivities of at least four channels of a more-than-three-channel sensor in the test color measurement device, linearly regressing the spectral sensitivities to a least-square best fit to Commission International de l'Éclairage (CIE) color matching functions, wherein the linearly regressing is performed using a weighting function that is based on a square root of a spectral power distribution characteristic of the emissive display or of a type of the emissive display, and computing a set of initial fitting coefficient values from the linearly regressing.