[sane-devel] Worsening Scans from Epson Perfection 1640

Karl Heinz Kremer khk@khk.net
Sat, 27 Jul 2002 20:07:36 -0400


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I have never seen something like this before. It really seems that
your scanner has a serious problem. I checked the log, and it looks
OK.=20

What you have in the 150dpi image is not a misregistration of
the color channels: You are getting the green data twice. The copy=20
is sent in place of real image data that is lost: When you look
at the first line, the letters "HAT" only show the bottom portion,
the top is missing.

Karl Heinz



On Sat, Jul 27, 2002 at 07:16:04PM -0400, Roy Murphy wrote:
> I wrote some time ago with problems with scans at high resolutions.
> Over time, the problem exhibits itself at lower resolutions.  I'm
> now thinking that I got a piece of garbage scanner.
>=20
> The symptoms are at high enough resolutions, there is poor
> registration between color layers.  Stripes in the scan appear=20
> with the image in ne color only offset from their proper location.
> scanimage --test passes all tests.
>=20
> These scans illustrate the problem.
> http://www.panix.com/~murphy/50dpi.pnm is fine.
> http://www.panix.com/~murphy/150dpi.pnm has stripes.
>=20
> The output from setting SANE_DEBUG_EPSON to 128 can be found in
> http://www.panix.com/~murphy/epsontest.txt.gz
>=20
> I would appreciate it if someone would take a look.
>=20
> --=20
> Roy Murphy      \ CSpice -- A mailing list for Clergy Spouses
> murphy@panix.com \  http://www.panix.com/~murphy/CSpice.html
> _______________________________________________
> Sane-devel mailing list
> Sane-devel@www.mostang.com
> http://www.mostang.com/mailman/listinfo/sane-devel

--=20
Karl Heinz Kremer                                  khk@khk.net
PGP Key at                 http://www.khk.net/download/khk.asc
EPSON Sane Backend:                         http://www.khk.net

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