I have a synthetic image of the ColorChecker (see the attachment, or here "Derived from GretagMacbeth L*a*b* D50 data, sRGB": http://www.babelcolor.com/main_level/ColorChecker.htm#ColorChecker_images). All colors are exactly the same as specified in ColorChecker.cie file, after conversion from Lab to sRGB using Bradford adaptation from D50 to D65. I have this synthetic chart in ColorChart.tif. I run the following: scanin.exe -dioap ColorChecker.tif ColorChecker.cht ColorChecker.cie I see that all the patches are located properly on diag.tif. I then run: colprof.exe -v -y -qh -bn -ax -U 1.0952 ColorChecker It says that peak error is less than 0.01 deltaE. I apply the profile using tifficc.exe and the result file differs from the source no more than on 1-2 RGB points. But when I apply the same profile to the image with all RGB colors, I see significant difference, about 10-15 RGB points. Why? What arguments should I use with colprof to obtain an identity profile? I don't want my profile to spoil a "perfect camera". How to achieve that? ----- Best regards, Mikhail Matrosov
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ColorCheckerMini_sRGB_from_Lab_D50.png
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