On Monday 01 January 2007 05:26, Graeme Gill wrote: > What do you mean by "2.2 gamma profile" ? The Argyll profile looks > appropriate for a CRT display with a native gamma slightly higher than > 2.2. The vcgt tag corrects this to gamma 2.2, and the profile device > curves reflect an overall response of gamma 2.2. The other profile only > make sense if it is working with a display with a native gamma of 4.8! > (ie. native gamma 4.8 * correction 0.45 = calibrated behavior 2.2, as > reflected in the TRC's gamma 2.2) - ie., it is a very peculiar profile > as far as I can tell. What I don't understand is how a profile set the gamma of a monitor? Is it done with [rgb]TRC curves? Then, the vcgtag curve is a correction to linearize the monitor response with given gamma? am I right? > Not being the author of xcalib, not without some effort. Can you clarify > a little how xcalib and dispwin behave on these two profiles (ie. > description of four cases). I attached another profile, from xcalib package (gamma 1). Here is a table to summurize what I see: Profile Loader vcgtag [rgb]TRC I see ------------------------------------------------------------------- gamma_2_2.icc dispwin gamma 2.2 gamma 2.2 bright " xcalib " " normal gamma_1_0.icc dispwin linear linear normal " xcalib " " dark A901HT.icc dispwin linear¹ gamma 2.2 normal¹ " xcalib " " normal¹ ¹close to... -- Frédéric http://www.gbiloba.org