Hi the other Martin ;-) Martin Weberg wrote:
I did the following conversions. No tiffgamut used. 1. collink -G -ip -cmt -dpp ProPhoto.icm ISOcoated_v2_eci.icc devlink.icc 2. In Photoshop I converted Bill Atkinson's Lab Test Page to ProPhotoRGB colour space. 3. Then, conversion cctiff -ip ProPhoto.icm -ip ISOcoated_v2_eci.icc rgbinfile.tif cmykoutfile.tif 4. and cctiff devlink.icc rgbinfile.tif cmykoutfile.tif The whole image from step 4 is really desaturated compared to 3.
That's consequential. In step 1 you create a gamut mapping that compresses the whole, huge ProPhoto space into ISOcoated_v2. In step 3 you use the precalculated gamut mapping of ISOcoated_v2 to compress a much smaller gamut (AFAIK something like the Pointer space) to ISOcoated_v2. Step 3 gives you more saturation, but clips everything outside the Pointer space.