Gerhard Fuernkranz wrote: > Graeme Gill wrote: > > Something carefully selected is needed for spectrally flat neutrals. > > Pure K print on a good substrate may be OK, but it depends on > > the black ink involved. CMY etc. is not going to be flat enough. > > Unfortunately the same applies e.g. to the GSxx ramp of IT8 targets. > Even if the chromaticity of dark gray and light gray patches happens to > match, it is just a metameric match, not a spectral one. > Yes, just for this reason I've choose the much more expensive target with flat-spectrum white, gray and dark patches. It's the X-Rite Digital ColorChecker SG. There is a quite small number of patches in the target and I've got a good results with ArgyllCMS Matrix+Gamma profiles. But I didn't find an alternative for the X-Rite target yet.