Wow! I'm starting to get the hang of it, Graeme. You really have put some sound thinking into dispcal and you should be commended for that. I just realize what that initial menu you put up right after instrument calibration is for! I thought it was just some kind of static series of display stats but, far from it! I love what you let us do in that initial menu. Wow! So far, because I use dispcal on an LCD monitor, I can only use the White point and White level check. But I have a question. Suppose, through the white point that I achieve just the white chromaticity I want, what's going to happen thtough calibration if I leave the parameter Target brightness set at some value that I realize now I should not specify? Like, suppose I defined -b90 and, after iterating on the White point, I get precisely the chromaticity I want but at 91 cd/m2, what is dispcal going to do? Lower the brightness but compromise my careful White point setting? Sounds logical. Does that mean that if I want dispcal to use the "native" white point and "brightness", once set by me with its assistance, I should not specify those parameters? I'm a little confused. I'll continue to experiment... Roger Breton