>The tags you quote are used just for matrix profiles. If you remove >those tags from the profiles so that only the XYZ cLUT tags remain, >do they still work ? (I bet they won't). > >ie. what you are seeing is that some applications fill in both >cLUT and matrix tags, and then the CMM will choose what to >use. It's hard to know which profile type is actually being used >though, and in this case it seems that you think the XYZ cLUT is >being used, but in fact the XYZ matrix is being used. Using >Argyll profiles it's clear what is being used and what is not. Thanks for the info, that makes perfect sense. I never realized that the XYZ LUT profiles from other programs always included Matrix profile tags to fall back on. >It sounds like this is not possible because Windows XP doesn't handle them. I guess that means both Windows and Firefox 3.5 don't support XYZ LUT profiles, hmm. I was stumped for months about why it wasn't working. Now that I realize what the problem is, any chance of adding an option to include those Matrix profile tags to fall back on like other programs do? I expect that other profiling applications do that to enable you to use XYZ LUT profiles as the default monitor profile in Photoshop, since Photoshop always uses whatever you have installed as the default profile in Windows. If you have better idea of how to make it the default monitor profile in Photoshop that would work with the current version, I'm open for suggestions. As a somewhat related question, is there any reason why Argyll refuses to make an ICC 2.4.0 Matrix profile (with A2B & B2A tables) like you can with LUT profiles? This is another thing it seems other profiles applications are able to do (create ICC 2.4.0 matrix profiles), but for some reason Argyll always makes a ICC 2.2.0 profile whenever you tell it to make a matrix profile. Am I overlooking something again?