Hi Graeme, I've tried it with tif files and I see the same problem. All the files are here: http://www.irelandupclose.com/customer/argyll/mygamtest.zip You can view the two spaces with mygam-and-profile.wrl Robert -----Original Message----- From: argyllcms-bounce@xxxxxxxxxxxxx [mailto:argyllcms-bounce@xxxxxxxxxxxxx] On Behalf Of Graeme Gill Sent: 10 July 2014 03:07 To: argyllcms@xxxxxxxxxxxxx Subject: [argyllcms] Re: Custom Illuminant robert@xxxxxxxxxxxxxxxxxx wrote: > What is also interesting/puzzling is that mygam.gam is made from very > desaturated images, and yet its gamut is bigger in places than > HP_Z3100_CANSONPHOTOHIGLOSS_ARGYLL_LG.icc (iccgamut/viewgam). Hmm. This seems like it's a bug in tiffgamut, when handling jpg files :-( With the bug fixed, yes they have a small gamut. Workaround - convert to .tif and try it again. Graeme Gill.