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RE: filmscanners: Scanner resolution (was: BWP seeks scanner)

At 04:28 PM 6/15/01 -0400, Austin wrote:
>> The red channel, OTOH, is the one with the best contrast,
>> almost always.
>I believe the green has the best contrast, and is the sharpest.  Even on the
>snippet you sent me, I believe green has far better contrast, and is the
>sharpest.  Blue was muddy, and red is not near as sharp.

Of your paragraph above (in general, not specifically 
that JPG "snippet") I would agree that blue is usually 
the muddy channel.  I can't agree on the rest of it 
though -- it's contrary to my own experience and to what 
I've read.

Well, Monroy/Moody agree with you that the green 
channel has the best sharpness... but they also 
claim that red has the best contrast, which lines 
up with my own observation.

Quite often, I'll apply USM to R and G, and then 
do Gaussian blur (say, 0.5 - 1.5 pixels radius) 
on the B channel, to soften the noise a bit.

>> According to Biedney/Monroy/Moody ("Photoshop Channel
>> Chops") the conversion to grayscale in Photoshop uses
>> the following proportions:  30% red, 59% green, 11% blue.
>And that gives you a fuzzy conversion...

So the wizards at Adobe got it wrong? <g>

rafe b.


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