8.
HOME STORAGE
8.1 TEMPERATURE & RELATIVE HUMIDITY
8.2 FREEZING YOUR FILM
8.3 THAWING YOUR FROZEN FILM: STAGING
8.4 ALTERNATIVE LOCATIONS FOR STORAGE
The ideal conditions
are in a controlled environment. Low temperatures and low humidity improve
the chemical stability of motion picture film. Under normal conditions,
i.e., room temperature (about 70F) and moderate humidity (50% RH), color
dyes fade, and triacetate base film decays at an unacceptable rate for
long-term preservation of the materials. Cold and dry are the best conditions
for the storage of film. A home freezer is the best option for long-term
storage where access to the film is not required on a frequent basis.
Long-term is defined in this case as longer than several months. Freezers
and refrigerators control the temperature, but don't adequately control
the amount of water in the air. Therefore, moisture-proof packaging is
required to control the humidity in the microenvironment.
8.1 TEMPERATURE
& RELATIVE HUMIDITY
Fresh film stored at normal household conditions (70°F and 50% RH)
will have an average lifespan of 40 to 50 years before significant signs
of decay occur (e.g., vinegar syndrome and color dyes density loss). Reducing
the temperature by 15 degrees Fahrenheit increases that number to 100-125
years.
The recommended conditions for extended-term film storage are between
40-50 F and 20%-40% RH (relative humidity). [Preservation
Calculator] Excessively dry air (below 20% RH) can lead to film becoming
brittle, while damp conditions will compromise the benefits of cold temperature
and invite mold growth. Good air circulation will help prevent mold growth,
but mold is possible any time the RH remains above 70% for more than a
few days.
Rapid changes in
either relative humidity or temperature should be avoided. Many people
assume that freezing is dangerous for film, but tests have shown that
film is not damaged by a freeze/thaw cycle in controlled settings. There
is a great danger, however, in condensation accumulating on the film so
film should be frozen in steps to avoid this.
8.2 FREEZING
YOUR FILM: FIVE EASY STEPS
Make sure that the film and packing materials are room temperature before
beginning. It does not take long for film materials to equilibrate thermally.
However, if the film was previously stored in a humid environment it may
take two to three weeks to equilibrate to a drier climate.
This may be done
by keeping the film in a can with the lid off in a room where the RH does
not exceed 50-60% at room temperature. These conditions are necessary
for the room in which you will prepare your film for freezing. Do not
prepare film for freezer storage on a hot and humid day, or moisture will
be trapped with the film in the bag and can.
If you have the space
and the funds, you should consider buying a freezer just for your film.
Depending on the size of your collection several options could be considered—e.g.,
a household freezer or industrial freezer.
1. Seal the cans or boxes with archival tape to make them as airtight as possible.
2. Use heavy-duty zip-lock freezer bags (3 mil or thicker).
3. Enclose one or several cans in the freezer bag and seal the bag with tape. Minimize the amount of air inside the bags. Label the bags clearly so they can be read without opening.
4. Double-bag the sealed bag containing the film and seal the outer bag with tape as above. Optional: enclose a moisture indicator in between the inner and outer bag.
5. Place in the freezer in an area where it is least likely to become punctured. Inserting cardboard supports between the packages will improve the stability of the stacks.
8.3 THAWING
YOUR FILM: STAGING
When going from cold storage [38 F/ 30% RH] to normal room conditions
[68 F/ 50% RH], film should first be brought into an intermediate staging
area in order to avoid condensation. The climate of the staging area should
ideally be midway between both the temperature and the relative humidity
levels of the cold storage and the working environment so that the film
never reaches its dew point. Put simply, film should go from a freezer
to a refrigerator and then to the workroom.
The length of staging
time needed depends on the mass of the film; a single small roll will
reach its equilibrium point faster than a large reel or a stack of small
reels. Six 400 ft. rolls of 16mm film will reach a usable point in 25
minutes and will be fully acclimatized in about three hours. When moisture-proof
bags are used, the minimum usable point will be slightly less because
the condensation will occur on the outside of the bag, not on the film.
Nevertheless, it is always a good idea to leave films out for at least
an hour before using them.
When it is necessary to remove the film from cold storage for use, it should be allowed to come to room temperature before any attempt is made to open the outer bag.
8.4 ALTERNATIVE
LOCATIONS
If cold storage is not an option, where then should film be
stored? Look around your house for possible storage locations and consider
the following.
- Do not store films
in an attic. In the summer this is too hot, and the temperatures vary
too much throughout the seasons.
- Don't store film
near heaters, plumbing pipes, radiators, sprinklers, windows, electrical
sources, or sinks.
- Do not store film
in direct sunlight.
- Avoid high humidity--do
not store in a basement. Most basements are quite humid and perfect
for mold. Also, there can be danger of flooding.
- Avoid exterior,
south-facing walls or locations that receive direct sunlight.
- For films with
magnetic soundtracks, keep away from magnets such as those found in
stereo speakers as well as heavy-duty electrical cables.
- Avoid any locations
near chemicals, paint, or exhaust. Chemical fumes, including those found
in everyday air pollution, when combined with a high relative humidity
can cause film to deteriorate and images to fade.
Many independent filmmakers leave their original materials in storage in film laboratories. Before doing this, question the lab about their storage facilities and keep tabs on the lab, as there are countless stories about films being lost after a lab has moved, been sold, or gone out of business.