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<tt>Hi all,<br>
<br>
I have a problem with my HP3670c scanner: when I scan some
documents in sequence, the first page is good (clear and bright),
but the following are much darker. </tt><tt><tt>If I leave the
scanner idle for some time (20 min or more), the pattern
repeats.<br>
</tt><br>
</tt><tt><tt>I've packed three consecutive scans of the same
document (white paper, black printing) as an example:</tt><br>
<br>
   scan 01: <a class="moz-txt-link-freetext" href="http://filebin.ca/1hi6F5IRZ0nq/scan01.tgz">http://filebin.ca/1hi6F5IRZ0nq/scan01.tgz</a><br>
   scan 02: <a class="moz-txt-link-freetext" href="http://filebin.ca/1hi6c0tiBGDJ/scan02.tgz">http://filebin.ca/1hi6c0tiBGDJ/scan02.tgz</a><br>
   scan 03: <a class="moz-txt-link-freetext" href="http://filebin.ca/1hi6tBYqo94r/scan03.tgz">http://filebin.ca/1hi6tBYqo94r/scan03.tgz</a><br>
<br>
Each .tgz file has scanned image (jpg file), a lot of debugging
.pnm files, and the debugging output of the Genesys backend.<br>
<br>
The scans were performed using scanimage:<br>
<br>
  /usr/bin/scanimage --device </tt><tt><tt>genesys:libusb:001:004</tt>Â
\<br>
                     --buffer-size=512               \<br>
                     --resolution 300dpi --mode Color \<br>
                     --brightness 25 --contrast 0<br>
<br>
I also tried including the option "--clear-calibration", but
apparently nothing changes.<br>
<br>
I'm using the last SANE backends (1.0.25 stable, built today from
Git) on Raspbian:<br>
<br>
 # scanimage -V<br>
 scanimage (sane-backends) 1.0.25git; backend version 1.0.25<br>
<br>
 # scanimage -L<br>
 device `genesys:libusb:001:004' is a Hewlett Packard ScanJet
3670c flatbed scanner<br>
<br>
Do you have any suggestions on how to solve this issue?<br>
<br>
Carlos<br>
<br>
</tt>
<div class="moz-signature">-- <br>
<font face="Helvetica, Arial, sans-serif"><it><a
href="http://dainf.ct.utfpr.edu.br/%7Emaziero">Prof. Carlos
Maziero, PhD</a></it><br>
<small><i>DAInf/UTFPR - Curitiba PR, Brazil</i></small><br>
</font></div>
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