The DEC ones I've seen are extremely high
resolution - from memory,
something
like 11 x 13 A4 pages on a fiche around 1" x 1.5".
I'm not sure what the current scanner technology is like, but not so long
ago
consumer-grade stuff just wouldn't handle that kind of density; even the
ones
coming somewhere close were relying on lots of interpolation rather than
raw
resolution.
There IS something that can be done, although very troublesome.
You have the reader. It projects a fairly good image on the screen. Why
not turn the lamp of the scanner off and scan the screen? :o)