Re: LAB as working/interchange space
Re: LAB as working/interchange space
- Subject: Re: LAB as working/interchange space
- From: Steve Upton <email@hidden>
- Date: Thu, 31 May 2001 10:34:53 -0700
At 9:00 AM -0400 5/31/01, Roger Breton wrote:
I think I have not clearly explaining myself, here. The case I am trying to
describe is that of "opening" a CMYK file from disk. The way I understand it
Is there actually a "conversion" taking place at that stage? Doesn't the
CMYK pixels remain unaltered? Doesn't Photoshop only need to figure how to
display those CMYK pixels on the monitor? And correspondingly resort to the
A2B1 Tag supplied in the embedded ICC profile (Device to PCS - "ICC Lab")?
Ah..right, there is no conversion of the data in the file but
Photoshop does use the profile to convert colors to screen for
viewing.
Further, the Lab readouts in the Info palette becomes the values off that
A2B1 Tag or the values of the CMYK Working Space?
Lab values are not in the file so they are calculated as you
suspected, from the CMYK values in the file using the profile.
Also - I don't want to fan the fires on the subject of this post -
Lab as a working space - but I do have a comment on it:
I had the feeling that part of this thread was about storage of color
data - and tonal resolution, etc - and part of it was about editing
tools.
LCH makes for great editing tools but why do we confine our thinking
to using LCH in the Lab space? Even though LCH is easily derived from
Lab (and vice versa), I see them as very different beasts as one is
good as an editing/understanding tool (regardless of the storage of
the file) and the other is a much-discussed translation and perhaps
storage space.
Am I missing something here?
Regards,
Steve Upton
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