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From: jb@falstaff.mae.cwru.edu (Jim Berilla)
Subject: Re: digitizing microfische - how?
Message-ID: <1991Jun6.045833.19859@usenet.ins.cwru.edu>
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References: <91152.035047ATDYW@ASUACAD.BITNET> <1991Jun5.184025.17868@mercury.cair.du.edu>
Date: Thu, 6 Jun 91 04:58:33 GMT
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In article <1991Jun4.151733.20348@smsc.sony.com> dce@smsc.sony.com (David Elliott) writes:
> [...]          Even a good 400dpi greyscale/color scanner should be
>able to produce a large enough picture to be usable.

In article <1991Jun5.184025.17868@mercury.cair.du.edu> troby@diana.cair.du.edu (Thorn Roby) adds:
> [...]
>I doubt that a 400 dpi scanner would provide enough information 
>to be useful. If the medium transport problems could be solved, it's
>possible that a slide scanner (Nikon, Barneyscan, Microtek) might 
>provide enough resolution (2000-4000 dpi). But my guess is that unless
>you're going to do a lot of this your easiest route is to print the
>fiche to paper and scan the paper.

Reality check time.

I think that Thorn Roby is right.  On the fische that I have in my hand, a
page measures about .2" by .26" (5 by 6.5mm).  A random line selected from
one of the pages has 97 characters.  The horizontal resolution would be
.8 pixels per character at 400 dpi.
-- 
      Jim Berilla / jb@falstaff.cwru.edu / 216-368-6776
"My opinions are my own, except on Wednesday mornings at 9 AM,
           when my opinions are those of my boss."