Newsgroups: comp.graphics
Path: utzoo!utgpu!news-server.csri.toronto.edu!torsqnt!lethe!tvcent!comspec!scocan!simon
From: simon@sco.COM (Simon Tooke)
Subject: Re: Can a handheld scanner scan an x-ray?
Organization: SCO Canada, Inc.
Date: Thu, 20 Jun 1991 21:01:51 GMT
Message-ID: <1991Jun20.210151.25075@sco.COM>
Sender: news@sco.COM (News administration)

From: bkirby@cs.umr.edu (Bill Kirby)
> I need to scan x-rays (lit from behind).  Can a handheld scanner do this?

In a related vein, I (with my handheld scanner) have been trying to
scan black&white negatives with limited success.  The problems are
the same, and no matter what I do, I get much better results (more clear
and more grey levels) scanning a contact print of the negative.

Here is what I have noticed so far:

1) Scanning on a lightbox doesn't work if the light is flourescent(sp.)
   I have not tried backlighting with incandescent(sp.? again?)
   lighting and suspect incandescent powered by a filtered DC source
   to be best.  The problem is wavy lines caused by lamp flicker.

2) Scanning with a silvered (or matte-silver) (i.e. either side of a
   bit of tinfoil) doesn't work.  I had high hopes for this, but the
   whites are washed down to grey.

3) Best results so far are simply scanning with reflective white paper
   behind the negative.

For scanning Xrays, I assume the resolution requirements are less than
I require, since my original is only a 35MM negative.  You might have
reasonable luck with white paper.

Anybody else have suggestions?  I'm trying to (a) avoid making a contact
sheet, and (b) build up a digital catalogue of my images.

-- 
===============================================================================
Simon Tooke                  SCO Canada, Inc.                    (416) 922-1937
130 Bloor St. West. Suite 1001, Toronto, Ontario, Canada 
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