RE: filmscanners: Cleaning slides (PEC tips)

["Brian Bisset" <bisset@home.com>]

[mailto:owner-filmscanners@halftone.co.uk]On Behalf Of Laurie Solomon
Sent: Sunday, April 29, 2001 8:28 PM
To: filmscanners@halftone.co.uk
Subject: RE: filmscanners: Cleaning slides (PEC tips)


>I tried to remove a fingerprint from a film strip yesterday only to
>find that it's embedded in the emulsion.

>Alas, it is my understanding that fingerprints are not just caused from
grease alone; but fingerprints also have some acid connected with them which
after a period of time begin to eat into the emulsion.  When this happens
there is nothing that will remove the etched in fingerprints.  In order for
things like PEC 12 to be truly effective they have to be applied early
before the acidic factors start to come into play.<

***********

You're right... The oil in your skin is acidic enough that over time, it
will affect the emulsion.  There are a couple of "tricks" you can try, if
it's a pretty important scan...

One (easy method), soak the film in lukewarm water (maybe a little
PhotoFlo), get the emulsion to swell again.  A little *gentle* cleaning with
*clean* fingertip can be done as well, but be careful as the emulsion is
very delicate at this point.  Don't soak too long (overnight), as the
emulsion can actually slide right off the acetate.  Hang dry, and your
fingerprint problems should be better, if not gone.

Two (radical method), if after that treatment, you still have fingerprint
(or scratch) problems, you can try this if you are brave (and desperate):

The Oil Bath.  This is an old drum scanner trick... (I'm an old drum
scanner).  Get a glass slide mount, the type that sandwiches the film
between two thin sheets of glass.  The next part requires practice,
patience, practice, patience, etc.  Use a neutral oil like maybe unscented
baby oil or similar.  I've only used scanner mounting oil, but to me it felt
like slightly thick baby oil.  I'd practice on an old slide that doesn't
matter first.  Place a couple of drops on the (clean) mount.  Place the film
on top.  Put another couple of drops on top of the film, and close the
mount.  The oil should cover the entire slide, top and bottom.  If there
isn't enough oil, you'll see the oil edge in the scan.  Too much oil, and
you've got it everywhere.  Tip the slide on edge and lean against something,
letting the excess drip into a paper towel, etc.  Once you're satisfied that
no excess oil will drip into your scanner (HORROR), clean the outside of the
mount, and scan away!  I strongly suggest that you position your scanner so
as to keep the slide horizontal.

The oil greatly reduces/removes dust, fingerprints, scratches, Newton's
rings, etc.  This also solves your curved film/focusing issues, but as it is
a major pain in the *ss, it is best left as a matter of last resort.

Brian