[sane-devel] Re: Re: Re: epson 3490 - transparency unit problem

[patrick deflandre]

Oliver Schwartz a écrit :
> Hi,
> 
> I've now adapted the quality calibration code for the 2480 and enabled 
> it for the 3490. It's a pitty that you solved the problem already ;-) 
> otherwise it would be nice to know if quality calibration solves it, 
> too 
> 
> The code is in CVS now, it should show up in the snapshots tomorrow - 
> please test.
> 

I've download the snapshot tonight, and make some test on it.
The quality calibration seems to work as expected, until the 1200 dpi. I 
  don't know exactly what is a quality calibration, but I guess it would 
had solve my previous problem since we clearly hear the stepping motor 
during the calibration process.

But I have always problem above the 1200 dpi. The resulting scan is not 
always bad. I explain :

- at 2400 dpi :
I have done several try, at least a dozen.
Sometimes it's all dark, sometimes all white, sometimes a succession of 
colored bands, and sometimes I have a good scanning, but at least it 
doesn't scale the entire selection I have made on the preview screen.
And I have always the shaking between line. (and I am sure I have the 
latest snapshot of the snapscan backend and of xscanimage frontend)

- at 3600 dpi :
it's in part all the same, except that when it's work, the scan cover 
the entire selection I have done. The shaking seems always visible, but 
I am not sure because of the quality of my film.

Those problems arise with or without quality calibration.