CMYK

I finally coded up and got running a RGB-to-CMYK conversion that is based on the physical properties of the printing device. The (perhaps insane) idea I have in mind is the following: Our RGB images of SDSS galaxies, if you view them on a normal RGB monitor, have a definite, quantitative relationship between the light hitting your eyes and the intensity hitting the telescope. It is non-trivial and non-linear, but it is quantitatively traceable and (lossy) invertible. When we print these out on a CMYK printer, this is not true, in part because the RGB-to-CMYK conversion is heuristic and doesn't in any way model the physical process of light hitting the page, being attenuated by the ink, and then reflecting. This process, for example, is multiplicative (not subtractive as is usually said). It is multiplicative with multipliers less than one, and (strongly) wavelength-dependent. The model I have built of this process can (in principle) make it once again true that the reflected light from the page (when viewed with a standard room illumination, say) has properties that are quantitatively and (lossy) invertible back to the intensity falling on the telescope. Why do I do these thing?