plustek@linuxhacker.org

Subject: Shading problem on HP2100C and Negative scanning on EPSON
From: Gerhard Jaeger
Date: Mon, 14 Oct 2002 10:39:25 +0200

Hi there,

yesterday I found some problems in the shading correction that
affects esp. LM9831 based devices like the U12, Bearpaw 1200 and
HP2100C.
Based on version 0.44-7 I fixed that and named it 0.44-8 (to be
found in the test section at www.gjaeger.de/scanner/plustek.html).

There also seem to be some problems during negative scanning
on the EPSON Photo devices. This might be the same problem.
But I also detected here some problems in finding the correct gain values.
This is currently als a problem for my Plustek negative scans.
Till can you please try version 0.44-8 with and without calibration!
(option skipCalibration). To fix the red channel problem, you might
also use option red gain and set this value manually to a reasonably
good value...

Thanks guys for testing
  Gerhard