the idea is that the tri-stimuli necessary to present a single color/grey should be independent between each other, or in other words, if a correction is needed to tweak the greyscale for your monitor, this correction will be valid and held for the whole colorspace in a very linear fashion...
a single color A(rgb) has to be comprise of three indipendent stimuli (perfect metamerisms) as
A(rgb) = A(R, 0, 0 ) + A(0, G, 0) + A (0, 0, B)
in decoupling display, a stimuli is a blend os poor light source, poor filters that concur to form an image that is pleasing thru additions and subtractions of other color, or in other words you do not get the purity of the stimuli but a blend that approximate it. In that case a 1D LUT is NOT a good model representation of your calibration but a more dense 3D LUT is necessary.
It is similar to the cross talk you get in the film negative/positive process... |