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I've been very happy with my Photocal experience. My profile (on a Mac) is 2,888 bytes. For reference the manufacturer's profile is 998 bytes. -- Tom Ferguson http://www.ferguson-photo-design.com > From: Garry Wiegand <email@example.com> > Subject: Re: PhotoCal+Spyder experience > > CDTobie wrote: >> Garry wrote: >>> But when I inspect the PhotoCal-generated profile, I see that the profile >>> contains no color-based information: it is simply a gray-scale adjustment. >> >> Not true; the info loaded to your video card is only gamma curves for the >> three guns, as that is all the video card can handle, but the actual profile >> is a true Matrix based profile capable of adjusting the RG&B phosphors to >> correct primary colors as well as setting gamma curves fro the channels. > > This is the contents of the profile, as reported by the Diblook program: > > ind signat elementoffset size > 0 'desc' 252 64 > 1 'rXYZ' 316 20 > 2 'gXYZ' 336 20 > 3 'bXYZ' 356 20 > 4 'rTRC' 376 524 > 5 'gTRC' 900 524 > 6 'bTRC' 1424 524 > 7 'wtpt' 1948 20 > 8 'cprt' 1968 40 > 9 'TCPt' 2008 32 > > No AtoB or BtoA matrix is included. > > Also... I just dumped out the bytes in those rTRC/gTRC/bTRC "gamma" color > ramps... the three lookups are indeed byte-for-byte identical. > > Thus my assertion that Photocal does not do color profiling. > > For comparison, the default profile provided by my monitor manufacturer is 25 > times larger and does include the full A2B0 and B2A0 matrices, along with a > wealth of other information. I'm not sure there's even enough information in > the Photocal profile to allow programs to check gamut. > > Maybe I have a problem on my end. When you inspect your own Photocal > profiles, do you see a file size of only 2040 bytes, like my own? Does > Diblook show you some conversion matrices? (Do OptiCal profiles look any > different?) > > Note, I do receive one error message at the end of the Photocal process on my > system: "Problem associating profile with monitor". Which I fix by loading > the profile into my Win2000 by hand. - Turn off HTML mail features. Keep quoted material short. Use accurate subject lines. http://www.leben.com/lists for list instructions.
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