Pascal de Bruijn wrote:
I _think_ these are photo paper targets... In what way would this affect the results?
Photo papers use three colorants (CMY), so the resulting spectra are always a combination of those three spectra. The real world has many different spectra that appear to be the same color to our eyes, and such a chart is only exercising one choice of them. So as a result it is (theoretically) possible to model a typical RGB sensors response to such a chart exactly, even if the sensors spectral sensitivities aren't much like that of the human eye. Exposed to real world spectra, the profile for such a sensor created this way might be rather inaccurate. Graeme Gill.