Mikhail Matrosov wrote: > Yes, that works. But I thought I need full power of cLUT to calibrate a > camera? Hi, If you are going to use a model with a large number of free variables, then you need to set them using a large number of test patches. 24 are not enough. Argyll's cLUT's do have a smoothness constraint, but this doesn't make unconstrained cLUT points conform to an additive model. > How is "single gamma+matrix" enough? It's enough if it matches the behaviour of your device. Perfectly additive devices can be modelled perfectly by curves + matrix. Graeme Gill.