[sane-devel] Colored vertical stripes with Visioneer Xerox DocuMate 510

[Mike Kelly]

On Mon, Oct 04, 2010 at 06:19:32AM +0200, stef wrote:
> Le Saturday 02 October 2010 19:33:18 chris guirl, vous avez ?crit :
> > On Mon, Sep 27, 2010 at 12:31 PM, stef <stef.dev at free.fr> wrote:
> > >        forgot to check that your scanner was supported by the lexmark
> > > backend. Is it the case ? Sometimes scanners are merely relabeled
> > > models.
> > 
> > I don't know. On sane-project.org the model is listed as unsupported.
> > I have noticed the other Xerox DocuMate scanners are supported by the
> > avision backend. I'm unsure how to find out which backend is being
> > used when I run xsane.
> > 
> > >        Shading correction is varying from backend to backend with the
> > > capabilities of the underlying hardware.
> > 
> > I have thought that it could be the problem you described above - the
> > white-calibration area is dirty. However I can't imagine what kind of
> > dirt would make this pattern...I uploaded a sample here:
> > 
> > http://sqrville.org/software/colored_bands.png
> > 
> > 
> > Recently, I was able to make a few successful scans. I can't reproduce
> > this now or figure out what made it work and what made it stop working
> > later.
> > 
> > 
> > Doing some more testing, I noticed that the scanner has thinner bands
> > of discoloration (about half the width of before) at a resolution
> > setting of 600dpi.
> > 
> > 
> > It is also worth noting that, to get the scanner working at all, I had
> > to add this line to /lib/udev/rules.d/40-libsane.rules:
> > 
> > # Xerox DocuMate510
> > ATTRS{idVendor}=="04a7", ATTRS{idProduct}=="0446",
> > ENV{libsane_matched}="yes"
> > 
> > Chris
> 	Hello,
> 
> 	this scanner appears to be supported by the avision backend. I think your 
> scans may be affected 'warming up'. When the lamp isn't warm enough, light is 
> varying, so scanned data is different other time. This fools shading 
> calibration. When the lamp is stable, shading works better.
> 
> Regards,
> 	Stef
> 
Hi Chris,

To track down this Avision problem, it would be helpful to have a debug
log of a scan.

Could you generate a debug log with the following command and attach it to
your reply?
  env SANE_DEBUG_AVISION=7 scanimage 2> avision.log


Thanks,

Mike
(:

-- 
--------Mike at PirateHaven.org-----------------------The_glass_is_too_big--------