This year, we're getting "clubcard": to print our annual calendars. However, living in the world of reflected light they accept artwork in "CMYK": colour space, and not "RGB": . This opened up the can of worms that we had mostly been ignorant of before -- colour management. There are lots of resources on the web for how to set up a workflow for colour management. However, I needed to stitch a pages from different sRGB sources, and convert them to CMYK. The best way I found to do this was: * rasterize the images to "TIFF": in RGB space. I used "ghostscript": * get sRGB and CMYK colour profiles from "Adobe": * use "LCMS": (Little Color Management System) to project the images from RGB to CMYK * compress the resultant tiffs and hand them off Although ghostscript can rasterize directly to CMYK TIFFs, I was unable to find how to apply a colour profile to the process, and the results were poor. In the future, I'll just use "Scrubus": to generate the whole thing directly in CMYK.