Dear Graeme! I wanted to quickly test the 1.1.0 RC3 and found a possible bug in colprof. This resulted in "Program has encountered an invalid operation and will be closed" (the culprit seems to be the "-aX" switch. "-ax" (small "x") works. > colprof -v -y -D"Display A" -ql -aX -cpp -dmt HyundaiN220W_Test colprof: Warning - *** Calibration file 'HyundaiN220W_Test.ti3'doesn't contain keyword COLOR_RE P, assuming RGB *** No of test patches = 214 colprof: Warning - *** Calibration file ''targ' tag'doesn't contain keyword COLOR_REP, assuming RGB *** Estimating white point Approximate White point XYZ = 0.952165 1.001648 1.082231, Lab = 100.063680 -2.36 3454 -18.835821 Creating optimised per channel curves Initial White Point XYZ 0.952165 1.001648 1.082231, Lab 100.063680 -2.363454 -18 .835821 About to optimise temporary matrix 100% About to optimise input curves and matrix 100% About to optimise output curves and matrix 100% About to optimise input curves and matrix again 100% About to optimise input, matrix and output together 100% About to create grid position input curves Create final clut from scattered data *************************************************************************** Doing White point fine tune: Before fine tune, rel WP = XYZ 0.964200 1.000000 0.824900, Lab 99.999998 0.00000 7 0.000007 After fine tune, rel WP = XYZ 0.964200 1.000000 0.824900, Lab 99.999998 0.000007 -0.000003 Creating fast inverse input lookups White point XYZ = 0.952165 1.001648 1.082231, Lab = 100.063678 -2.363448 -18.835 813 Find black point Black point XYZ = 0.004331 0.003187 0.007028, Lab = 2.878658 5.082604 -8.306386 Display Luminance = 51.277870 Done A to B table creation Setting up B to A table lookup Creating B to A tables Rev cache RAM = 750 Mbytes There is 1 rev cache instance with 750 Mbytes limit There are 2 rev cache instances with 375 Mbytes limit 100% Done B to A tables There is 1 rev cache instance with 750 Mbytes limit colprof: Warning - *** Calibration file ''targ' tag'doesn't contain keyword COLOR_REP, assuming RGB *** Creating matrix and curves... 100% Find white & black points Initial white point = 0.951677 1.001160 1.082136 Initial black point = 0.005375 0.004348 0.007402 Fixup matrix for white point After white point adjust: Matrix = 0.434987 0.327834 0.201379 0.224125 0.737438 0.038437 0.012671 0.139683 0.672547 Done gamma/shaper and matrix creation Profile done =============================== ps. Please pay no attention to the displayed matrix - I have reduced the number of measurement points from 4000 to 214 to conserve speed (I included the HyundaiN220W_Test.ti3 - it is part of an old set of measurements made with a self-compiled Argyll version, predating 1.1.0 RC1). The same crash happens when I used the full set along with -qm.