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From: rosiekm@rl.af.mil (Mark Rosiek)
Subject: Re: Kodak Photo CD for Black and White
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Date: Sun, 30 Jul 1995 23:24:33 GMT
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Photo CD converts RGB data into Luma, Chroma, Chroma (YCC) data. For black
and white photography the first chroma is set to a constant 156 and the
second chroma is set to a constant 137.  
For further info see: 
1.)Photo CD Information Bulletin 045 May 1994
2.)Photo CD: Quality Photos at Your Fingertips, John Larish, Micro
Publishing Press, Torrance, Califonia 1993

In article <3ve35i$207@news.acns.nwu.edu>, phantom@merle.acns.nwu.edu
(James H. Choi) wrote:

> I did not find any explicit statement from anywhere, but I 
> calculated that the photo CD (PCD) uses eight bits per color in 
> all resolutions.
> 
> Now, the question I have is how it handles black and white 
> scans.  Does it just set the same value for RGB thus making 8 
> bit depth for black and white photograph?  If that's the case, 
> I cannot imagine it being sufficient to capture all high light 
> and shadow details of a black and white negative.
> 
> I await more insight from better informed individuals.
> 
> James Choi

-- 
This may be only my opinon, and does not necessarily reflect reality in any of it forms.
