robert@xxxxxxxxxxxxxxxxxx wrote: Hi Robert, > test between the two. My problem is that I don't really know how to set up > this test, in particular how to know how much UV there is in my illuminant. > Perhaps there's an indirect way of estimating that (illumread clearly does > this, but I don't understand the plots enough to be able to say that > illumread indicates that this particular illuminant has high UV and this one > has low UV). Well, the answer is that "illumread -v" will indicate how much UV it thinks is in the illuminant, in rather arbitrary units. However, on checking exactly how this works, I'm distressed to discover that illumread has not actually been working since ArgyllCMS V1.4.0, when I re-factored some code to add support for M0/M1/M2 :-( :-( :-(. I've updated <http://www.argyllcms.com/disptools_win32_v1.7beta.zip> and also updated <http://www.argyllcms.com/Argyll_dev_src.zip> if you would like to test with a working illumread. Graeme Gill.