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Digital BW, The Print

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Message

Re: Linearizing a QTR Curve

2005-02-21 by Tom Husband

--- In DigitalBlackandWhiteThePrint@yahoogroups.com, "Louis Dina"
<lbdina@c...> wrote:
> 
> Tom,
> 
> Photoshop rounds all L* values to integers and I don't know of any 
> easy, painless way around that.  Since matte papers have L* values 
> that usually go from the mid teens for shadows to 96-98 for 
> highlights, and glossy papers go from single digits in shadows to 96-
> 98 in the highlights, you should be okay using integers.  Dividing 
> the overall dynamic range by 21 still gives you about 4 L* units 
> difference from step to step depending on the paper you are 
> profiling.  You will still get a pretty darn good linearization.  
> Spectros and densitometers can give you finer precision, but you may 
> not see all that much of a difference as long as your scanner is 
> reading raw data that hasn't been adjusted or converted during 
> scanning.  (Auto features should be disabled when scanning).
> 
> Give it a try and see how it comes out.  
> 
> Lou

Thanks Lou.  I'm pretty sure I have a raw scan so I'll just proceed
and see what it looks like.

Thanks again, your posts are always very informative.

Tom

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