RE: Shadow Detail and LS2000 Color Management

[Jerry Lodriguss <jml@xxxxxxxxxxxx>]

At 11:16 AM 4/19/2002 -0700, you wrote:
>That's interesting info. I hadn't realized that sRGB wasn't a simple gamma
>curve. But anyway, if you take your two test images in Photoshop, and use
>Levels to stretch the low end of the scale just to see if the detail's
>really there (even though this makes the rest of the picture look like
>crap), it's obvious that the scanner color management _is_ clipping off some
>of the darkest detail.

Yes, I agree. When the scanner color management is used, it does clip the 
darkest detail. No doubt about that.

The pixel values stay the same after the profile is assigned in Photoshop, 
so it seems that gamut mapping is involved too, as well as the generic 
profile of the scanner.



>As to gamut mapping, you could certainly try selecting different conversion
>intents (e.g., absolute colorimetric) just to see if that makes the
>conversion any better. But I think that has to do with how extremely
>saturated colors are converted, not blacks. But this is black magic...

I tried different rendering intents, and it didn't seem to make any 
different, the colors shifted, but the shadow detail was lost. And the 
rendering intents was just for a profile conversion, all I did was assign a 
profile.

It may be voodoo, but there is no magic in the way it looses the shadow 
detail. <G>

Jerry



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