Re: [long] Overall usage impressions

John Labovitz (johnl@meer.net)
Mon, 25 May 1998 23:01:22 -0700

Paul D. Robertson <proberts@clark.net> said:

> Oliver once again stepped to my rescue and explained the
> true gamma correction method for xscanimage, and after pressing the gamma
> button and entering a value, things got much, much better.

Could you write more about this? I've been scanning black and white
negatives (Tri-X Pan, mostly) and found a curve setting that worked,
but i did it by hand (using the straight-line tool at the bottom of
the left-hand curve toolbar), not using a gamma number. I haven't had
as good luck scanning color transparencies (Kodak EPD).

I've been meaning to ask a question (to the list in general, not just
you, Paul) about gamma -- does setting the gamma (either by number or
by manually shaping the curve) affect the actual scanning operation?
That is, does the gamma get downloaded to the scanner and used to
shape the scanned samples, or is just something that's applied to the
data once it comes back from the scanner?

And while I'm at it, what's the `Highlight (%)' slider do?

john

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