[sane-devel] Simplified installation procedure for Redhat Fedora Linux 1.0 and Epson 1670 scanner, also a report of a bug?

[Martijn van Oosterhout]

On Mon, Feb 09, 2004 at 02:40:31AM -0800, Jeff Silverman wrote:
>    The problem also describes a problem: the registration of the colors 
> breaks down at densities beyound 600 DPI.  Curiously, the problem is 
> worse at 900 DPI than at 1200 DPI.  I have an example - to avoid 
> flooding this list, I put the examples on the 
> http://www.commercialventvac.com/~jeffs/epson1670andFedora.html page.

Ok, seems you have a colour offsetting problem. I know with the scanner I
have (hp5400) that if you choose a high enough resolution, the xwidth of the
data exceeds the internal transmission buffer. This has a tendancy to cause
received data to be misterpreted as the wrong colour and at the wrong place.

Given your sharp horizontal lines after which it breaks it would seem to be
something like that. I've never done it myself but you should be able to
(maybe in GIMP) seperate the image in the three planes, one for each colour,
and move them around until they line up. Once you find the pattern, you can
code it in.

BTW, maybe you should put up thumbnails to demonstrate the problem and let
people click on the images for size. I'm on a fast connection and it took
ages to download.

Hope this helps,
-- 
Martijn van Oosterhout   <kleptog at svana.org>   http://svana.org/kleptog/
> (... have gone from d-i being barely usable even by its developers
> anywhere, to being about 20% done. Sweet. And the last 80% usually takes
> 20% of the time, too, right?) -- Anthony Towns, debian-devel-announce
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