Thank you for the explanation. At this point I think that it is better to use the black offset control offered by my Lacie 324 to keep the video LUT less stressed. There is a recommended way to set them? Marco Il giorno 13/ago/2010, alle ore 02.15, Graeme Gill ha scritto: > Marco N. wrote: >> On my NVIDIA GeForce 7300 GT I can't set the black point to 0 (native). >> Dispcal seems ignore the -k0 -A1 -f0 settings and it correct always the >> three gamma curve of the LUT. >> http://lh5.ggpht.com/_Ogy3SF4bQ9Q/TGQ9niAuPKI/AAAAAAAAAIk/jzWMEBz18P4/s144/1.png >> Is it a bug? > > No it's a feature! > > A calibrated display should have a progressive response. > This means that from 0 giving the minimum output, it should > start to change as soon as you change the input. > > If a display native response has a "dead band" where nothing changes > as you change the input, then this results in a vertical jump > in the calibration curve. > > So the curve you see indicates that your display doesn't change its > output until it gets (about) 5 as in input, so the calibration curve > starts at (about) 5, so as to give a progressive response. > > Graeme Gill. >