RE:Best Lab profile...
RE:Best Lab profile...
- Subject: RE:Best Lab profile...
- From: Henrik Holmegaard <email@hidden>
- Date: Fri, 23 Mar 2001 10:06:30 +0100
"Vanderlinden, Thomas M." <email@hidden> wrote:
a) Discovering that there are multiple Lab profiles.
This was a rude reality check on my plans to archive our files
in device-independent, "known" space.
Going back three years Apple has been asked to change the title of
the bundled 'Generic LAB Profile'. This unity profile is part of
common UI choices because Lab D50 is an archival / editing space
which the 'Generic XYZ Profile' isn't.
When users set up their spectrophotometers or a print profiler, the
white point of Lab comes into what they are doing.
This means that in the normal course of an ICC workflow, the Lab
white point must be explicitly stated for the user to successfully
navigate the desicion path.
Apple may take the position that according to the ICC specification
one and only one white point is allowed, that is, D50. But then again
it isn't written in the stars that Lab must be D50. In the PostScript
CMS the white point of Lab isn't defined.
Only one in several thousand users will know that the ICC
specification stipulates that Lab be D50. So if simply writing
'Generic Lab D50 Profile' ihelps all those other users, I don't see
the harm. Note that -
a. The QuarkXPress 4.0 documentation explicitly states the white
point of Lab supported by the release, as the List discussed way back
three years.
b. The Heidelberg Newcolor UI (due on the Mac for OS X in the not too
distant future) explicitly notes older D65 import (from Linocolor 5.1
and earlier) and current D50 export.
c. GretagMacbeth software likewise states the white point of Lab.
b) Adobe's TWO profiles, which both show up as
"Adobe Photoshop CIELAB", in ColorSync pick lists,
though one has a file name of "pslabpcs.pf",
and the other has a file name of "pslabint.pf"
These are Kodak profiles autoinstalled with Photoshop. They have
different Finder and internal names, hence ColorSync lists them twice.
--
Henrik Holmegaard
TechWrite, Denmark