Dear David,
this problem is with most of the LCD scanners, which indeed have very little
to no depth of focus. The big old fashioned scanners with a fluorescent tube
inside sometimes had a depth of focus of more than 15 mm and could be used
like a big format camera. I now sometimes use a Canoscan LIDE 2000, who have
enough depth of focus to scan Dentalium shells in those cases I have no
digital camera and adequate light at hand.
Best regards
Bernd Sahlmann



----- Original Message -----
From: "David Kirsh" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Monday, February 22, 2010 5:53 AM
Subject: [CONCH-L] scanners


> No, not the movie.
>
> I recently got a Lexmark copier/fax/scanner with high resolution that
> works well...everything except for the fact that I can't scan shells the
> way I did on an older scanner. I used to be able to scan shells down to
> about 10mm at high resolution and be able to enlarge the images with good
> results.
>
> The Lexmark images have virtually no depth of field so that any
> 3-dimensional object will be out of focus and pixilated where it's not
> touching the glass. Yet a flat document can be enlarged quite a bit and
> remain sharp.
>
> Has anyone encountered or solved this problem with a recent scanner?
>
> David Kirsh
> Durham, NC
>
> "When you're chewing on life's gristle, DON'T grumble. Give a
> whistle!" --from Life of Brian
>
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