I am a bit confused about the Lab values in the BtoA LUTs. In my case, the BtoA LUTs are 33 x 33 x 33 and the abcissa for the points in the LUT are like:
L a b 0 0 0 0 0 1 0 0 2 ... 32 32 30 32 32 31 32 32 32As I understand things for this LUT, an a or b value of 0 corresponds to -128 and an a or b value of 32 corresponds to 127.
My calculations then show that a value of 16 for a or b would not correspond to 0. Instead 16 corresponds to a value of -0.5.
16*255/32-128 = -0.5I know this must be incorrect. Can someone please try to explain to me what I have missed.
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