RE: Photoshop 6/7 problems with OptiCAL Monitor profiles
RE: Photoshop 6/7 problems with OptiCAL Monitor profiles
- Subject: RE: Photoshop 6/7 problems with OptiCAL Monitor profiles
- From: "Bob Chase" <email@hidden>
- Date: Thu, 13 Feb 2003 13:51:15 -0500
C David,
If I'm reading your results correctly, you've verified a certain level of
consistency of the tags in the profiles produced by various utilities and
instruments, and seem to have *not* experienced the OptiCAL/Photoshop
profile translation issue I reported. EyeOne profile tags also translate to
PS properly, and there were "minor" translation differences with Optix.
I appreciate your looking into this, but I have to tell you that ColorVision
themselves acknowledged the monitor profile Photoshop translation
discrepancies via tech support email. And I know it isn't merely a Windows
issue, because I demonstrated the problem to them on their own (Mac)
equipment at their booth at PhotoPlus Expo 2002 at the Javits Center last
Fall. From what I've seen the profiled primaries values, as demonstrated in
the OptiCAL Information palette numbers (and as matched in the older OptiCAL
.ams files), are quite different from the profile primaries values seen by
Photoshop.
Of course "quite different" to some may be insignificant to others. A
typical example I found was: Blue y: .072 in OptiCAL Info palette, .064
(rounded up) in Photoshop. Does this difference have any more impact on
Photoshop image display than using a generic set of primaries vs measured?
ColorVision tech support said that the issue was seen with any ICC profile,
not just profiles created by ColorVision. Perhaps some utilities have the
same issue with Photoshop, and this is actually an Adobe fault with their
"simple" monitor profile structure. Either way the primaries numbers are
not being translated properly, by what I would consider a significant
amount. I would think this has a negative impact on the accuracy of
Photoshop's image display - a critical part of a PS color management
process. Since Photoshop is a primary target for monitor profiling
utilities, I would think the profiling utilities companies would try to
provide a solution, even if they technically are already ICC compliant. The
old .ams file output option previously supplied by OptiCAL had been a
solution.
If you'd like, I can send you screen prints off-list to demonstrate typical
results I see. Let me know. -Bob
PS - Very interesting to see results of your experiment between the various
utilities, and even between colorimeters and spectrophotometers.
In a message dated 2/13/03 9:55 AM, email@hidden writes:
>
Well, I refuse to dig out a CRT and a DTP92... but with an LCD and a
Spyder,
>
here is what I get:
>
Little x and little y values as reported for Gamma 1.8 Whitepoint Native
>
(about 6500) or 6500 profiles with the EyeOne, the Spyder and OptiCAL and
>
Optix with the new Sequel calibrator compared to the colorant tags in the
>
profiles reported x, y values; all for the same monitor. All on a Mac, OS
>
9.2, Photoshop 7.
>
OptiCAL values vary from the Optix values in Photoshop by a maximum of .02.
>
Optix and OptiCAL vary from the EyeOne by a maximum of .04. This may be the
>
colorimeters siding together against the spectrophotometer.
>
The EyeOne and OptiCAL/Spyder values between Photoshop and the tag values
are
>
accurate to the rounding errors (one reports more digits than the other),
>
while Optix varies from itself (Photoshop to tags) by a max of .02.
>
Note that these are all values well away from 5000k. They are quite similar
>
to the scatter I get measuring printed patches with a range of devices.
>
So your proposal that OptiCAL is doing something wrong could be viewed
>
instead as monitor calibration at large working in a way you don't care
for.
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