Re: Display Profiling
Re: Display Profiling
- Subject: Re: Display Profiling
- From: Henrik Holmegaard <email@hidden>
- Date: Tue, 20 Mar 2001 09:40:51 +0100
David wrote:
And how do you apply these LUT based monitor profiles??? The Monitors control
panel won't show them as monitor profiles, and therefore Photoshop can't pick
them up as monitor profiles... using them as LUT based RGB workingspaces
would be possible as of PS6, but thats hardly what we what from a monitor
profile. My point was that no matter how sophistocated a profile we can build
it gets dumbed down to single number gamma curves before it can be applied.
Not quite -:)
a. The Apple monitor calibration framework only builds matrix-based
monitor profiles. It doesn't build LUT-based monitor profiles. Both
ProfileMaker and Viewopen build LUT-based monitor profiles (Viewopen
1 only built LUT-based monitor profiles for high-end scanning
workflows which the desktop didn't support, Viewopen 2 (also called
VO4) gives you a choice between matrix-based and LUT-based).
b. The Monitors control panel has a 'ColorSync Profile' (: Monitor
Profile) 'scrollbox' (: popup) that shows both matrix-based and
LUT-based monitor profiles.
c. Apple ColorSync 1.0 only supported matrix-based conversions for
all device types including printers, making ProfileMaker 1.0 a tad
limited -:). Adobe's technology in Photoshop and Acrobat are
similarly limited in their functionality, Photoshop 4 converted
LUT-based ICC printer profiles into it's proprietary relative
colorimetric Adobe Separation Tables which if I'm not far off the
track are a type of matrix-based profile, Photoshop 5 supported
LUT-based ICC printer profiles but went proprietary on LUT-based RGB
monitor profiles, and RGB and LAB color space conversion profiles.
However, Photoshop 6 is open - I think -:).
d. The ColorSync 3.0 control panel is still proprietary in its
approach to RGB LUT-based color space conversion profiles. We talked
about this on the List a while ago.
I'll post an analysis of the ColorSync 3.0 control panel in a while.
It's funky in it's use of ICC specification terms like 'Input' and
'Output' profiles -:).
--
Henrik Holmegaard
TechWrite, Denmark