[sane-devel] Epson Perfection 1250/Photo 64-bit

[Charles Lindsey]

I refer you to the thread starting at
  https://alioth-lists.debian.net/pipermail/sane-devel/2013-February/030905.html
with further examples of the same bug at
  https://bugs.mageia.org/show_bug.cgi?id=18003 and
  https://bugs.mageia.org/show_bug.cgi?id=18003
It also got reported to
 
https://alioth.debian.org/tracker/index.php?func=detail&aid=314019&group_id=30186&atid=410366
but with the demise of alioth.debian.org/tracker it is impossible to say what 
further action was taken. I believe the version of sane then was 1.0.25.

Now, 7 years later, I am using version 1.0.27 (as supplied with ubuntu 18.04 - 
bionic) I find the bug is still there. I am not going to describe it again, 
because what I am now seeing is exactly what was reported to this list in 2013. 
Specifically, using simple scan, the first two scans work as expected, and the 
third scan shows the banding. I can also report that the workaround (to set 
option altCalibration 1 in plustek.conf)appears to work, though what damage it 
does to calibration I do not know. I suspect that the bug arises from the change 
form 32-bit OS to 64-bit OS, as reported in the original thread, though I have 
not managed to load a 32-bit OS to test this.

I bought the Epson Perfection 1250 on ebay, and I chose it because it uses the 
plustek backend, and that was one of the few backends that was not marked as 
"not supported". So I hope you guys can help me to fix this.

I fully accept that I may be one of the few sites in the world trying to use 
this scanner, but if you guys can tell me what tests you would like done, and 
suggest changes to the source code that might help, then I am happy to join in. 
I have plenty of experience in hacking my out of messes such as this one.

Charles H. Lindsey ---------At my New Home, still doing my own thing------
Tel: +44 161 488 1845                    Web: http://www.cs.man.ac.uk/~chl
Email: chl at clerew.man.ac.uk              Snail-mail: Apt 40, SK8 5BF, U.K.
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