Dark scans (HP Photosmart)

Bill Wohler (wohler@newt.com)
29 Dec 1999 16:52:03 -0800

I've got an HP Photosmart. The scans from slides have been very,
very dark. Almost black. I upgraded to scanimage (1.0.1) that
has a new option called ps-exposure-time. I set this to the max
(300%) which helped, but the scans are still way too dark.

Beefing up the --brightness and --contrast options washes out the
image.

Perhaps the --custom-gamma option will help me out. How do I use it?

I've also tried brightening the scans with the GIMP, but I'm not
very good and the results are not very pleasing and it takes me a
long time to get there besides.

To see whether it was the hardware or software, I tried installing
the HP software under Windows. It scanned the slides beautifully.
Any way to simulate the processing the HP Windows software does with
the HP SANE backend? What is interesting about the HP software is
that it appears the scans are pretty dark as the scan is in progress
(but not as dark as on the Unix side); when the scan completes, the
dark image suddenly "brightens up".

Any tips appreciated.

-- 
Bill Wohler <wohler@newt.com>
Say it with MIME.  Maintainer of comp.mail.mh and news.software.nn FAQs.
If you're passed on the right, you're in the wrong lane.



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