[sane-devel] Degrading images: Plustek OpticPro UT16

[rhn]

Hello,

the scanner I am using has a peculiar problem, where scanning consecutive images causes the image quality to degrade: the left part becomes yellow in vertical streaks that increase in numbers; the right part becomes red. To get a completely yellow-red image, about 10 scans are necessary, regardless of options.

The backend for this scanner is plustek.

The problem occurs regardless of frontend. Xsane is particularly bad, because the 2nd of 3rd image can be completely yellow/red. Inserting a call to sane_close/sane_open between scans fixes the problem a bit - the 3rd image starts showing streaks.

You can find the effect of 5 consecutive scans of a white A4 page here: http://porcupinefactory.org/data/sane-scan.png
The command to obtain them: scanimage -d plustek -x 215 -y 20 --preview=yes -b --batch-count=5

I suspect the problem is somewhere in the backend.
I can make it through building, but how do I install and use a local copy of the plustek backend?

Cheers,
rhn