Following standards (naming PCS unity profiles)
Following standards (naming PCS unity profiles)
- Subject: Following standards (naming PCS unity profiles)
- From: Henrik Holmegaard <email@hidden>
- Date: Fri, 7 Dec 2001 17:08:29 +0100
John Gnaegy <email@hidden> wrote:
"Unity profile" ... uh, what is that? I don't remember seeing that term
in any of the Apple help files or documentation. We didn't
randomly pick a word out of a hat.
A unity profile is a profile that does nothing, another term is
working space profile, though not all unity profiles are working
space profiles. 'Unity profile' is used in European color engineering.
ColorSync 3 should create unity profiles based on standards, as
indeed two are. These are 'Generic Lab Profile' and 'Generic XYZ
Profile', but only 'Generic Lab Profile' is also a working space
profile. As with RGB and CMYK, visual linearity is an editing issue,
and commercial software does not offer XYZ color pickers.
I'm not saying you didn't talk among yourselves within Apple, because
the Mac OS UI shows a tradition for being practical. I'm saying you
didn't phone your colleagues in other companies. Had you done so,
users wouldn't be struggling with Apple 'Generic Lab Profile', Adobe
'Adobe InDesign Default Lab', LOGO 'Lab Profile' and Photoshop 5
'Lab' (as embedding only) ... which is the same thing.
The ICC specification doesn't know what 'Generic Lab' is and it
doesn't know what 'Default Lab' is and it doesn't know what 'Lab' is.
It only knows ICC Lab D50 2 degree standard observer. Many users now
have instruments, many more than when I first raised this issue three
years ago.
Different industries use different white points as measuring
condition, e.g. the paint industry prefers D65. Different countries
have used different white points for proofing, Germany went from D65
to D50 while the US stayed D50 moving into ICC workflows.
The instrument manufacturers must sell equipment to more than one
industry and state the white point and color model in LDC displays
and software. This is correct in an open systems workflow where
endusers configure the system on site.
If I measure a spot color in Eye-One Share, the measuring condition
is stated as D50 2 degree standard observer. Using Eye-One Share the
measuring condition is autoset, as it is in other software used in
ICC workflows, some of which states the measuring condition and some
of which does not. If I use a spot instrument with a display, then I
must know what measuring condition to choose, if the instrument is
not hooked up to software that configures it for me.
If I wish to key this color into InDesign 1.5, what ICC profile
matches the standard measuring conditions - 'Generic Lab Profile' or
'Default Profile'? As a user I don't want to know what 'Lab D50 2
degree standard observer' implies technically. But when I configure
my workflow with products from different companies, I look for the
same name in different UI's because that is the basic identifier: The
name.
When the source Lab object is not in standard D50, I must choose a
source color space conversion profile for the incoming Lab object and
a D50 profile for the destination. This I can do say in InDesign 1.5
or iQueue, importing LinoColor 5.1 D65 Lab with the clearly labelled
D65 source profile, but how do I know the white point of the Apple
profile (: if I don't use InDesign's built-in Lab profile as
destination)? It is quite true as a US journalist has written that
Linotype-Hell did a poor job of stating its Lab, but Newcolor states
the white point of its Lab explicitly, as does other European ICC
software.
Every company can go its own way, that's its prerogative, but is this
really the point? If you people at Apple, Adobe, Heidelberg,
GretagMacbeth ... who make the products we are challenged to
configure on site all insist on reinventing the standard definitions
the ICC members have set to make things easier for each other and for
us, then what reason could you possibly give, other than that you
want it that way? Of course, that's also a reason, but is it a good
one?