Subject: Re: Scanning microfiche? (Long)

From: Chuck McManis <>
Date: Tue Aug 1 12:12:24 2000

To add to Mikes article (which was pretty darn complete BTW), I used to
work at the Image Processing Lab in the Engineering school of USC. The
lab's charter was image processing and we had a very nice "Micron" scanner
(I don't think it had any relation to the current Micron computer company).
Dial in optics gave you .001, .0001, and .00001 (100, 1000, and 10,000 DPI)
There was an option for 100,000 DPI that we didn't have but there wasn't
much call for it. The scanner was run by a PDP-11/55t (since scrapped :-()
that scanned to disk and then out to tape.

All of which says, consider looking for a local university to see if they
might have some high density scanning material. Of course it was a drum
scanner and it took probably 10-20 minutes to scan a single image (so
that's a couple of years for 10,000 fiche!)

However, if you "think analog" you'll see that you can in fact scan these
with a cheap scanner but you will need to optically expand them to get the
gain. Using a standard darkroom enlarger with a 10x enlargement to a piece
of onion paper on the bed of the scanner would work. A typical 600 dpi
scanner gets 600DPI effective that way (no interpolation). Once you have
the setup it could be relatively mindless work but not impossible.

Of course, it will always be a time and money kind of thing. At 0.07/image
how much is your time worth?

Received on Tue Aug 01 2000 - 12:12:24 BST

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