[sane-devel] bug with Canon N1240U in Lineart mode at 75 dpi?

Eric Ding ericding@alum.mit.edu
Tue, 30 Nov 2004 11:16:36 -0500


The lowest "next" resolution up is 100dpi; anything in between rounds
either down to 75dpi or up to 100dpi.  Things seem to work just fine at
100 dpi, though...

The latest version of sane seems to allow an attempt at 50 dpi; this
also fails in Lineart mode, but not in other modes.

Eric

Gerhard Jaeger <gerhard@gjaeger.de> wrote:

> Hi,
> 
> On Saturday 27 November 2004 20:24, Eric Ding wrote:
> > I'm using sane-backends 1.0.15 with libusb on Gentoo Linux with a Canon
> > N1240U scanner.
> > 
> > When I try to scan in Lineart mode at 75dpi, I get a few back-and-forth
> > pauses, then a significant buzzing sound as the scanner's (green) light
> > is on, but the light bar doesn't move at all.  Scanning in other modes
> > (i.e., Gray, Color) or in Lineart mode with higher resolutions (i.e.,
> > 96, 300, etc.) works fine.
> > 
> > Scanning with these settings using Canon's Windows driver works, so I
> > conclude that this is likely an issue with the SANE plustek backend.
> > Below find the stderr output of running
> > 
> >      scanimage --mode Lineart --resolution=75
> > 
> > with SANE_DEBUG_PLUSTEK set to 13. Have I found a bug? Can anyone
> > confirm or deny this behavior?
> > 
> > Thanks,
> > Eric
> [SNIPSNAP]
> 
> I've tested that here and have no problems so far. It might be, that the 
> motor settings for this mode are somewhat at or slightly beyond the limit
> so that some devices have no problems while others have...
> Can you do some more tests, i.e. increase the resolution and check when it's
> working?
> 
> Ciao,
> Gerhard
> 
>