# Re: Scanner question. Off Topic

becka@rz.uni-duesseldorf.de
Wed, 3 Mar 1999 01:43:52 +0100 (MET)

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Hi !

> Please forgive the intrusion, but since so many of you know your way
> around scanners, I thought perhaps someone might know the answer, or
> could point me to a source.

> Can scanners go out of focus?

Yes.

> I have a Microtek E3 and although text and copies come out great,
> photographs scan like they are out of focus. I use OS/2, but tried it
> with drivers in W3.1 and w95 as well and they always are out of focus.
> I am pretty sure its a focus issue as zooming in shows it to be blurry
> as can be, even in high res.

If the degree of blurriness is pretty insensitive to the dpi setting,
this really sounds like a focus issue. How do you scan text ?
In Black/white mode ? That is relatively insensitive to blurriness, as it
gets converted to only black/white, thus leaving no room for blur.

Try scanning some B/W image, or rather text in different resolutions in
true color mode to verify it. If it is a focus issue, you will probably
see grey "ramps" on all sides of a black/white transition.
The form of the ramps can as well give some indication of the kind of
focussing problem.

> Just wondering if the scanner is now useless, or perhaps I can adjust
> it?

Maybe. If you dare to disassemble it and try to find out how the optics was
supposed to work, there should be ways to adjust it. Reading up in some
physics book on how to adjust optics (there are some tricks like
autocollimation) might help as well.

CU, Andy

    --
    = Andreas Beck                    |  Email :  <andreas.beck@ggi-project.org> =

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