In a digital camera system, traditional input color transformations of raw data using a 3 x 3 matrix are replaced by two-dimensional lookup (2-D LUTs) tables that better approximate spectral reflectance characteristics. Chromaticity-like signals and an input scale factor are generated in response to raw sensor output values. The chromaticity signals and the input scale factor are mapped via 2-D LUTs into preliminary output signals and an output scaling factor. A final set of output color signals is generated in response to the preliminary output signals and the output scale factor. The 2-D LUTs are designed in response to spectral response curves generated on both the input and output side of the color transformation.