Ok, I think I've seen where I'm going wrong now. I know I want the native white point of the display, the minimum display brightness and a 2.4 gamma as recommended by yourself. So, all I need run is: dispcal -yl -v -m -qh outfile (making sure my display has been manually set to its lowest brightness) Then, (having already generated patches as above) use dispread with the output .cal as so: dispread -v -yl -k outfile.cal outfile Then create my shaper/matrix profile like so (ignoring description strings for the moment): colprof -v -qu -as outfile Then I just repeat the process from targen onwards, injecting the new profile into targen with 2000 patches, using dispread with the original outfile.cal, and finishing with: colprof -v -qu final_profile That should give me a nice high-quality profile. I can then update it fortnightly/monthly with: dispcal -u <pathtoprofile> Have I got it right? *fingers crossed*