Hello, 1) What does the ambient light condition option -a of dispcal actually do to the resulting calibration curve? I'm assuming that as the ambient light level increases, the overall gamma of the curve is increased, since a LCD screen needs a boost in apparent contrast in brighter surroundings--is this correct? If I use the sRGB calibration curve, is this option ever needed if you are not interested (and don't use) super-accurate monitors and pre-press type viewing arrangements? If I do use it, is the value of 200 lux (a fairly well lit office, I think) specified as "Typical ambient illuminance level" in the sRGB specification a good one to use, although I typically use my screen in slightly dimmer surroundings? (Florian Hoech's dispcalGUI reminds you to specify the ambient light condition when selecting the sRGB curve.), 2) Once I've made a profile that seems all right, is there any advantage in terms of further accuracy in using the black and white level luminance target options to set a black target just a tiny bit above the actual calibrated final min black level, and similarly to set a white levels just a bit below the calibrated final max white level, in the interest of providing the calibration algorithm with some fixed end points in the iterative curve fitting dance it seems to do? Say a min black level of 0.15 for a measured calibrated level of 0.1 and a max white level 2-3% below the measured calibrated level of the display? 3) Would using an existing LCD display profile to condition the colour values output by targen do anything useful for profiling that same LCD display using the minimum 500 patch size chart that seems recommended for such applications? I'm thinking that increasing the number of test values measured that are actually within the limits of the display might be a good thing, and that this is what the conditioning process does. Thanks for any help! Michel.