filmscanners: Scanning Mechanisms

[rafeb <rafeb@channel1.com>]

At 02:43 AM 7/21/01 -0700, Art wrote:

>Moving the film via a carrier, which is likely molded plastic, with
>plastic gearing, and also having it need to "mesh' with the motorized
>transport, and being that the carrier is prone to dust and dirt
>attraction and "the elements", makes it much harder to maintain
>integrity of precision movement.


Clearly the film has to be in SOME kind of carrier, 
whatever the scanner brand.  Austin's Leaf uses 
aluminum carriers (Beseler) but all the scanners 
I've owned have plastic-molded film holders of 
varying complexity.  Frankly, I feel a bit more 
comfortable with my negatives up against plastic 
than against metal.

There are hybrid schemes that work very well, such as 
the older SprintScans.  For all my griping about those 
old SprintScans, they do have a very elegant and 
well-executed scanning mechanism and optical bench.

The older SprintScans used a flimsy plastic film 
holder, but quite adequate for the purpose.  The 
film holder clicks firmly into place onto a moveable 
carrier, on precision linear slides (stainless steel,) 
within the scanner.  The film moves, during scanning, 
and with great precision -- even though it's in a flimsy 
plastic carrier.

The disadvantage of this scheme is that it does not 
support batch-scanning at all.  The scanner has no 
way to advance to the next image -- that has to 
be done by moving the plastic film holder by hand.


rafe b.