handled in total darkness or under safelight conditions
specified by the manufacturer.
Unexposed light-sensitive materials deteriorate
slowly with time even when the materials are stored
under ideal conditions. High temperatures and high
relative humidity accelerate this deterioration. You
should protect light-sensitive materials from the
harmful effects of temperature, humidity, x rays, gases,
and vapors that may be present in darkrooms, transport,
and adverse storage conditions. Storage instructions are
printed on the packaging materials of most photographic
products.
Kodak papers and sheet film are packaged in
humidity-sealed boxes to protect them from changes in
relative humidity (RH). Keep these materials in their
original packaging until you are ready to use them.
When the RH gets at 60 percent or higher for long
periods of time, not only do cardboard packages, labels,
and metal containers become damaged, but mold,
fungus, and bacteria start to grow. Fungi can destroy
film and paper by digesting the gelatin in them. Ideally,
film and paper should be stored below 50 percent RH.
The usable life of a light-sensitive material varies
with the type of material, but generally, color materials
deteriorate more rapidly than black-and-white
materials, and black-and-white materials with
high-speed emulsions deteriorate more rapidly than
black-and-white materials with slow-speed emulsions.
Cold storage in a refrigerator or freezer is
recommended for all light-sensitive materials; however,
refrigerators and freezers that contain food or unsealed
containers of liquids have a high relative humidity.
Therefore, food should never be stored in the same
refrigerator as film and paper.
Paper and professional film should be stored at
about 50°F (10°C) or lower in the original sealed
package. All film, including amateur film, must be
protected from extreme heat. Never store photographic
materials in extreme heat, such as in a glove
compartment, trunk, or the back window of a car. Once
opened, the original package should be used as soon as
possible. After opening, the materials are no longer
protected from humidity or chemical fumes.
When film or paper, black and white or color, is
removed from cold storage into a warmer atmosphere,
allow a warm-up time before opening the original
packaging; otherwise, moisture condensation may form
on the film or paper. The warm-up time for
light-sensitive material depends on the type of material
packaging, the size of the package, and the amount of
material.
The warm-up times for packages of paper is
considerably longer than for film. Paper is usually
packaged in larger quantities, 100 to 500 sheets per box
and in rolls up to 1,000 feet long. Short roll film and
magazines take 1 to 1 1/2 hours to warm-up. Large
packages and rolls of film and paper should be allowed
to warm-up to room temperature overnight or about 10
hours.
FILM AND PAPER EXPIRATION DATES
Each package of film is marked with an expiration
date. Ideally, the film should be processed before this
date for best results. If the film has not been used by this
date, it should be tested photographically to confirm and
determine its adjusted film speed and performance.
Much of the film and paper found in Navy inventory
has, in fact, expired. When not subjected to adverse
storage and handling conditions, the film is probably
still usable for a reasonable time. You should consider
the expiration date as a guide only.
Use light-sensitive materials of the same type in the
order of their expiration dates. The material with the
earliest expiration date should be used first. One
exception to this is when you know that a material of the
same type with a later expiration date has been subjected
to improper storage conditions; for example, if film or
paper has been sitting on a pallet on the flight ramp in
Diego Garcia for several weeks before being delivered
to the ship, you should test the material before using it.
Film and paper stored under unfavorable conditions or
film that has expired may have a loss of emulsion speed,
undesirable contrast changes, stains, color shifts, or high
gross fog.
2-11

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