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Digital BW, The Print

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Re: PhotoShop Histograms leading us astray?

2002-03-29 by flyfishingusa2002

For some reason yahoo has choosen to repost this? I didn't, has 
Yahoo gone mad?

Barry


-- In DigitalBlackandWhiteThePrint@y..., "flyfishingusa2002" 
<tflyfish@c...> wrote:
> I have been following all the threads regarding "Combing" 
and "Step-
> Wedges" with great interest. I have been looking at there 
Histograms 
> in Photoshop and trying to figure out what it was telling me. I 
have 
> been seeing a lot of "stray" information in the Histograms that 
> confused me, so I decided to try the following:-
> 
> 1  I did a selection of just the wedge part of the published 
> standard Step wedge by Jon Cone and MIS
> 
> 2  I, via PhotoShop 6, drew a simple rectangle filled with a 
> graduation from 0% - 100% grey.
> 
> Neither of the above gave me a "Clean" Histogram. I fully expected 
> #2 to do so. I see lots of little comb teeth and a variation in 
the 
> histogram height when I thought it should be constant.
> 
> Could it be that the "Combing" is something that Photoshop is 
> introducing and does not really appear on our finished print?
> 
> I have also noticed that on the step wedge that those little white 
> dividing lines do not appear between all the steps on some 
> magnifications and not on others.
> 
> I am no PhotoShop expert, but the above seems a little odd, maybe 
we 
> are all being lead astray by PhotoShop?
> 
> Barry

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