[sane-devel] Epson 3490

[Oliver Schwartz]

Hi,

> I don't have access to that information right now, so I'll check
> that tonight also.  It is whatever firmware came with the scanner -
> esfw52.bin.

yes, but at least for other epson scanners these firmware files are 
available in different versions. The filename is always the same.

Another thing that I'm interested in is whether only the size of the 
scan area is wrong or if the origins of the scan area are also not 
set correctly (i.e. options -l and -t in scanimage)

If it is always the same ratio of real distance to scanned distance 
(also for -l and -t) it is most likely that the calculation of the 
scan area is not handled correctly. That could be corrected by 
changing the value of pos_factor in function set_window() in 
snapscan-scsi.c. For the guy that developed the patch that didn't 
help, though.

> My main interest at this point is to understand whether this issue
> is something that can be solved with some patch to the backend, or
> whether it's inherently related to the scanner's firmware or
> something that is Epson-proprietary that the SANE developers won't
> get access to. Is anyone able to shed some light on this issue?  

I don't think that this is an unsolvable problem. It may be necessary 
to do some deeper analysis and maybe get some USB traces from the 
windows driver, though.

Also keep in mind that the scanner seems to work for at least one guy, 
so the solution can't be that difficult :-)

/Oliver