On 20 Mar 2013, at 01:13, Graeme Gill <graeme@xxxxxxxxxxxxx> wrote: > Are you converting to N-Color ? No, just plain old RGB to CMYK. > As far as I can tell, nothing pertinent has changed for non N-Color > TIFFs. Doing a tiffdump of a CMYK file created in 1.4.0 and 1.5.0 showed > no differences, and PS 6.5 loads both fine. > > Is there anything else to go on ? Sure, take a look at some tiffs -- here are a couple of 100x100 pixel grey squares: <http://rgb2cmyk.co.uk/i/GSq_CMYK_1-4cctiff.tif> <http://rgb2cmyk.co.uk/i/GSq_CMYK_1-5cctiff.tif> The only difference between them is the version of cctiff used. I can't open the 1.5 version using Photoshop CS5 or CS6 on a MacBook Pro or Mac Pro running 10.8.3 or any of the other Mac Pros we've got here running 10.6.8. No problem opening or viewing in any other application but Photoshop refuses. -- Maritn Orpen Idea Digital Imaging Ltd