Hi, I have tried to use my "old" Sequel Chroma 4 with ArgyllCMS spotread -v, but the program exits after reading the version number. The output from spotread is: Connecting to the instrument .. Version string = 5.0 ID character = 0xffffffff = ' ' Instrument initialisation failed with 'Not expected instrument model' (Instrument version number or ID byte not recognised)! Looking at i1disp.c, it is clear that the versions < 5.1 will not be accepted in function "i1disp_check_unlock". I'm willing to take the risk trying to modify i1disp.c, unless you positively know, that it will not work. So that's my question. Best regards Preben Soeberg