Film Preservation Basics
If you have some old films, they deserve the proper care to save them
for future generations.
Of course, most of the films we have were meant to be shown and
shared. A film sitting on a shelf doesn't serve its purpose.
Deterioration symptoms:
Wear
The most common kinds of wear are perforation damage, base scratches.
emulsion scratches and breaks. Perforation damage is usually
caused by either a malfunctioning projector, a misthreaded projector,
or a projector that has lost its loop. Base scratches appear as
black lines and are on the side away from the emulsion. When
duplicating a film, base scratches can be minimized by wet gate
printing. Emulsion scratches are green or white lines scratched
into the emulsion. There is no cure for emulsion scratches.
Color Fading
The most common problem with long term storage of film is color
fading. With B&W film you only need to worry about base
degradation (vinegar syndrome). Some film stocks fade very
little, and others fade severely. Generally, cyan (blue-green)
goes first, followed by yellow, ultimately leaving only magenta.
Eastmancolor from the about 1953 through 1982 is the worst, though it
can be quite variable. See my film stock identifier page
(link). Heat is the main accelerating factor. The quality of
processing also affects it, prints from some labs always fade severely,
others hold up much better under the same storage conditions.
Vinegar Syndrome
Vinegar Syndrome is a breakdown of the acetate base. When
deterioration occurs, acetic acid vapors are produced, creating a
distinctive vinegar aroma. The acid produced accelerates the
process. Keeping the film in a sealed can traps the vapors,
accelerating it further. Vinegar Syndrome causes the film to
warp, shrink and become brittle. High humidity and high
temperature speed the process. I suspect that residual processing
chemicals are a significant factor. Polyester base film is immune
to vinegar syndrome. The earlier diacetate film (before the mid
1940s) is less prone to vinegar syndrome, but often emits a camphor or
"mothball" smell due to the plasticizers used. Agfa stock emits a
peculiar odor, which should not be confused with vinegar syndrome.
Enemies of film:
Wear
Always keep the film path on your projector squeaky clean.
Naphtha, Filmrenew or alcohol on a cotton swab work well for this
purpose. When you acquire a projector, run a loop of blank film
through the projector several times to be sure that there are no burrs
that might scratch the film.
Heat
Heat is the main contributing factor to color fading, and accelerates
Vinegar Syndrome. Keep film as cool as possible. Never
store film in an attic. I try to keep most of my films below 60
deg. F (15 C) as much as possible. At the extreme, freezing film
will preserve it almost indefinitely, but care must be taken to prevent
condensation on the film.
Humidity
Humidity is the main contributing factor to Vinegar Syndrome.
Never store films (especially acetate) above 50% RH. Air
conditioning units help reduce humidity, and stand-alone dehumidifiers
are readily available. Extremely low humidity isn't good either,
storage below 20% RH can make the film brittle.
Cleaning film:
Never clean film with water or a water based cleaner. It is best
to use a cleaner made for film. I usually use Filmrenew which is
a cleaner with lubricant and conditioner. It is relatively cheap
and can help warped or brittle film. Naphtha can also be used, as
can pure alcohol, avoid rubbing alcohol as it often contains
water. All of these cleaners must be used under adequate
ventilation, as the fumes are hazardous. Film cleaner can be
applied with a clean soft cloth such as an old T-shirt.
Film preservation resources:
The Home Film Preservation Guide, an excellent resource for the novice
in film preservation:
http://www.filmforever.org
Conservation On Line at Stanford University, a great list of articles
on film preservation:
http://palimpsest.stanford.edu/bytopic/motion-pictures/
Image Permanence Institute at the Rochester Institute of
Technology:
http://www.imagepermanenceinstitute.org/index.html
National film Preservation Foundation:
http://www.filmpreservation.org
Home Movie Day, dedicated to the preservation of home movies on film:
http://www.homemovieday.com/
Video transfer resources at Home Movie Day:
http://www.homemovieday.com/transfer.html
Urbanski Film, source of film cleaner, editing supplies and
Molecular Sieves in smaller quantities (Larry specializes in providing
supplies to the amateur as well as to professionals):
http://www.urbanskifilm.com
Eastman Kodak's recommendations for film storage:
http://www.kodak.com/US/en/motion/support/storage.jhtml?id=0.1.4.11.12&lc=en
Please contact me if you have any
suggestions for improvements to this page.
Copyright 2004-2015, Paul Ivester. Please do not copy without
permission.