Oliver Schulz wrote: >> For recalculating an existing profile with new TAC, You need a complete >> new calculation of the the profile. > > Damn, that's what i wanted to avoid. :-) > How do color-managed applications which have in ink-limit setting > (Photoshop, i think) do this? Also, the littlecms tifficc converter > allows to set both a target profile and an ink limit (seems to work > fine), so it must be possible somehow to ink-limit a profile. The lcms API provides a function to create an ink-limiting CMYK -> CMYK device link transformation (this function is also used by the tifficc tool). But this function does not recalculate the colorimetry, but works rather heuristically directly in device space by downscaling C, M and Y proportionally (all three by the same factor), if C+M+Y+K is over the ink limit. This does not necessarily give colorimetrically correct results and may not result in an optimal gamut mapping, but it is computationally cheap and seems to give reasonably pleasing results, at least with reasonably well-behaved devices/profiles. With Argyll, I would do something like icclink -v -qh -G -cpp -dpp -kt -l310 \ EuroscaleCoated.icc EuroscaleCoated.icc limit.icc in order to create a perceptual device link profile which maps EuroscaleCoated to "ink limited EuroscaleCoated". Other than the lcms method, the latter one also honors colorimetry and will explicitly establish a perceptual gamut mapping between the gamut of the original EuroscaleCoated and the gamut of the "ink limited EuroscaleCoated". Resampling measurements from a profile with fakeread in order to create a new profile from the resulting "measurements" will of course always results in the loss of some accuracy (for resampling and recreating EuroscaleCoated, expect a loss of approx. 0.3dE avg, 2dE max. for the A2B1 table, with 5000 sample points and -qh; actually not half bad!). And recalculating an ink limited EuroscaleCoated profile from the scratch will also result in a perceptual intent with a different "personality" than the original EuroscaleCoated profile (this may be either desirable or not, depending on your taste), and it may need some fiddling to find -k... parameters which result in a similar black generation for the new profile as in the original one (note, when creating a device link, -kt can be used, which which inherits the K level from the source profile as far as possible, but when creating an output profile from measurements, this is not an option). On the other hand, applying the above mentioned device link to the CMYK data after applying the original EuroscaleCoated profile will almost preserve the original personality of the Euroscale profile, and change it only as much as necessary to enforce the ink limiting. But I also don't know a ready to use Argyll or lcms tool which can incorporate such a device link directly into the B2A tables of an existing profile (but it should indeed possible and not too complicated to develop one). Regards, Gerhard