Am 30.01.2011 20:03, schrieb Elena [service address]: > One was for example the option -kl of xicclu which I never noticed. Another > is the difference between Locus and Value in argyll jargon, I maybe stupid > but I didn't understand it yet. > My understanding is that "value" refers to an actual amount of K, while "k locus" refers to a relative amount of K (where locus =1.0 refers to the K value that would be selected by -kx, while 0.0 refers to the K value that would be selected by -kz). >> I however just discovered another gap of mine, till now I misunderstood that >> -kz actually generated NO K at all. "-kz" attempts to reproduce a given L*a*b* color exactly, using as little K as possible. If it happens that the given color can be reproduced without K, then consequently no K will be used at all. For colors which cannot be reproduced without adding some black ink (typically rather darker colors, near the gamut boundary), -kz does well generate non-zero K. > My strong suspect is that argyll fails not just because it has no checks > against discontinuities, but mostly because the .ti3 is noisy, and/or not > precise or dense enough in some dark areas. > I don't know yet whether this is really just noise or anything else. One would likely need to investigate all the involved cells of the A2B grid in detail - but that's quite tedious... Regards, Gerhard