Alexey Gribunin wrote:
Hello Graeme!You aren't doing the same thing though. The CIE values from the first are with a D50_0.0.sp illumination (UV and some blue filtered out). For the second, you are applying a D50 illumination, and the extra blue in it results in different values. If you do a:spec2cie.exe -i ref/D50_0.0.sp -o 1931_2 -n Test_UVCut.ti3 Test_UVCut_CIE.ti3Yes, it's clear. If I will do it, I will get Lab values compensated two times.
That's not the case. There are two separate things going on. One is changing the effective spectral reflectance values to allow for the different UV level. The other is the combining of the spectral reflectances with an illuminant to compute the XYZ tri-stimulus. The spectral values out of spec2cie -f have the first done to them, while the XYZ values have both, the illuminant being D50_0.0.sp. When you do the second spec2cie you need to use the same illuminant to get the same result.
But I need it compensated only once, in one step like this: spec2cie.exe -i ref/D50_0.0.sp -f -o 1931_2 Test.ti3 Test_UVCut.ti3
It is only being modelled once with this command. Graeme Gill.