Quartz wrote: > From what I understand, 'Jacobian matrix' has something to do with predicting > the response > curves so it can speed up measurement process. I believe that the errors here > mean the > monitor is too far out of whack and the predictions are failing. I don't want > to just put > the calibration speed slider on super slow mode though without a better > understanding of > what's going on. It just means that dispcal is struggling with either the consistency, or quantization behavior of the measurements. It shouldn't stop you getting a calibration. Rather than focus on such warnings, does the calibration and profile look any good ? Graeme Gill.