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Re: SMPTE meeting in NYC: film cleaning?



Dear Rob,

Last week's SMPTE meeting raised a number of important issues.
 Unfortunately, I would have to say that if one thought he or she was going
to get a definitive answer to the problem of film cleaning, it was a
frustrating evening.

Kodak, Lipsner-Smith and Technical Film Services (makers of a distilled water
film cleaner) had representatives there.  The Kodak rep went over the history
of film cleaners and some of the tests they've done on various cleaning
agents.  He also gave an excellent reminder to all who handle film in any
capacity: cleaning really begins with proper care and handling of the film to
keep it from getting dirty in the first place!

The Lipsner-Smith (solvent based) and TFS (water based) folks each gave a
talk on why they think their approach is best.  The TFS machine is very
interesting in that it only wets the film very briefly, just enough so its
brushes can wash the surface but not so much that the emulsion starts
softening.  It is by far the most environmentally-sound method of film
cleaning, except perhaps for PTR rollers, but many of the people in the
audience expressed their doubts about what might happen to cut negative or
original camera negative given such treatment.  The Lipsner-Smith rep pointed
out that aside from those issues, only solvent-based cleaning will remove oil
and grease marks from film.

Finally, a discussion was held by Donald Wanamaker of Environmental
Management, a firm that helps companies assess the risks of toxic/hazardous
chemicals, and assure that the appropriate OSHA, EPA, and state/local
regulations are met.  The overall conclusion reached was that all of the
currently known non-water solvents which may be used for film cleaning have
regulatory issues that will have to be dealt with.

In conclusion, the three things I got out of the meeting are:

1. Although perchloroethylene is now the film cleaner of choice, it requires
more care in handling, as it is considered a possible carcinogen and is about
ten times more obnoxious in the air than 1,1,1 trichloroethane was.  It is
not as good a film cleaning agent as trichlor was, and requires either more
drying time, or better drying equipment, compared to trichlor-based cleaning
machines.  It may be outlawed or placed under more stringent restrictions in
the future.

2. It is probable that multiple approaches to film cleaning will have to be
adopted in the future.  Facilities may need to install a water and/or PTR
roller based machine for general purpose use, and a solvent based one for
things that can't be cleaned any other way.  Rewash machines, and the
practice of rewashing film will probably become much more prevalent, at least
in film labs.  (Rewashing can and has been done for decades by simply running
the dirty film through part of the developing process again.  Unlike the TFS
cleaner, rewashing softens up the emulsion, allowing embedded dirt and minor
scratches to come out.  A rewash machine is similar to a film developer
except that it does not have a darkroom or first developing tank, which are
not needed.)

3. Adequate film cleaning is likely to become far more expensive than it is
now, if for no other reason than there are going to be new, strict
regulations that will have to be met.
Therefore, there will be a trend in telecine facility operations to put
things on a really strict clean-room basis and thereby minimize the need for
film cleaning as much as possible.

Christopher Bacon
DuArt Film & Video

--- End of forwarded message from KA2IQB at aol.com




-- 
Rob Lingelbach          | 2660 Hollyridge Dr LA CA 90068 213 464 6266 (voice) 
rob at xyzoom.alegria.com  | "I care not much for a man's religion whose dog or 
rob at sun.alegria.com	|  cat are not the better for it."  --Abraham Lincoln
rob at dagmar.alegria.com        KB6CUN	   http://www.alegria.com