III. Procedures for Photographic Materials

1. Priorities for Photographic Materials
2. Precautions for Photographic Materials
3. Salvage and Recovery Procedures for Photographic Materials
   1. General
   2. Procedures for Drying Prints
   3. Procedures for Drying Cased Photographs
   4. Procedures for Drying Negatives and Transparencies
   5. Motion Picture Film
   6. Microforms

III.1. Priorities for Photographic Materials

• Although all photographic materials are sensitive and require immediate attention, in general, prints are more vulnerable than film or negatives, color more sensitive than black and white. If negatives exist for prints, however, it may make sense to salvage only the negatives, and make new prints later.
• Color slides, negatives, and film should be treated professionally within 48 hours
• Some historic processes are extremely vulnerable to damage from water. If not air dried immediately, recovery rate is low (see procedures below for each). These include:
  • Wet collodion (collodion wet plate negatives, tintypes, Ambrotypes)
  • Daguerreotypes
  • Autochromes, Dufaycolor
  • Dye transfer prints
  • Deteriorated nitrate-base materials
  • Deteriorated acetate-base materials
  • Carbon prints and Woodburytypes

• If possible, seek the assistance of professionals for salvage and recovery of photographic materials because of the variety of processes and their sensitivity in general
• Do not allow wet photographic materials (both prints and films) to dry in contact with one another--the emulsions will soften and stick to adjacent surfaces, and may be impossible to separate--see below for procedures for keeping them wet until recovery can begin
• Do not touch the emulsion side of photographic materials

• Consult a professional if possible, but in general, the preferred recovery method for photographic materials is air drying, with the exception of microfilms and motion picture films. Film on long rolls can be handled more easily by reprocessing in mechanized processing machines by a professional processing lab. See procedures below for air drying for specific materials.
• For materials that cannot be air dried immediately, and for microfilms and motion picture films, keep them wet and cool by sealing them while wet in plastic bags and immerse the bags in cold water in clean plastic pails. Add ice to the water to keep it cool, especially when shipping them for treatment. Arrange for treatment as soon as possible. For black and white, emulsions separate in 3 days. For color, color layers separate, and dyes fade, in 2 days.
• If neither air drying nor arranging for treatment within the time limits above are possible, freeze materials as quickly as possible (quick freezing as in a blast freezer results in smaller (less damaging) ice crystals.

III.3.2. Procedures for Drying Prints

• Unframe and unmat prints, and keep identifying information with them.
• If prints have been exposed to dirty or salt water clean them by immersing them in cool clean water.
• Cover drying surface with absorbent paper, lay prints face up, and change paper when it becomes wet.

  Special considerations for the following prints:

  • Unmounted albumen prints -to prevent them from curling, dry with weights on the edges or under lightly weighted polyester web and blotters.
  • Carbon prints and Woodburytypes - the binders swell considerably, so dry these as quickly as possible.
  • Dye transfer prints - Dyes migrate so dry these as quickly as possible. If transporting them keep them horizontal.

III.3.3. Procedures for Drying Cased Photographs
(Daguerreotypes, Ambrotypes, tintypes in cases)

• Air dry cased photographs as soon as possible. Do not immerse in water and do not freeze.
• If water has gotten inside the case, dismantle and air dry all parts.
  • Remove the assembly from the case
  • Fold back the preserver frame
  • If there is sealing tape, cut it, and take the assembly apart
  • Lay photographs face up with components beside them on absorbent paper, and change it as it becomes wet

III.3.4. Procedures for Drying Negatives and Transparencies

• Roll film negatives - Dry emulsion side up on absorbent paper, and change paper as it becomes wet, or hang carefully on a line with plastic clips
• Sheet film negatives and transparencies - These have a gelatin layer on the back that could stick to paper. Hang to dry carefully on a line with plastic clips, or dry films emulsion side up on polyester web covered absorbent paper
• Glass negatives - Dry vertically by propping them up on their long sides or in racks. If broken, cracked, or with flaking emulsions, dry flat
• Lantern slides, Autochromes and Dufaycolor - If water has gotten inside, dismantle the slide and dry as glass negatives
• Color slides in plastic or paper mounts - Remove slides from plastic sleeves and pages. If a small amount, slides may be dried in their mounts if in a controlled environment. Otherwise, unmount slides, keep and dry the mounts if they have information on them, and hang slides on a line by edges with paper clips
• Deteriorated nitrate- and acetate-base negatives - The recovery rate is low. Dry these emulsion side up on sheets of polyester web over absorbent paper, and change paper as it becomes wet. If they are in an early state of deterioration they may be hung on lines with plastic clips to dry, but do not let them touch each other

III.3.5. Motion Picture Film

• If film is in cans, check if water has gotten inside. If only the containers are wet, dry them and relabel if necessary. If film is wet, fill the can with cold water, close the can, and pack into plastic bags and immerse bags in plastic pails filled with cool water. Add ice to keep cool, especially for shipping. Ship to a film processor for rewashing and drying as soon as possible.

III.3.5. Microforms

• Salvage only master films. Consider leaving copy films if they can be replaced.
  • Roll microfilm - If water has gotten inside the film rolls, keep rolls wet and in their boxes (add water into boxes if needed to ensure keeping them wet). Hold cardboard boxes and their labels together with rubber bands. Pack them into sealed plastic garbage bags and immerse the bags in plastic pails filled with cool water. Add ice to keep cool, especially for shipping. Send to a film processing lab as soon as possible.
    • If only a few rolls of film have gotten wet, they can be dried by winding over film rewinds (used for inspection) and cleaning with a film cleaner, which contains a solvent that encourages even drying.
  • Microfiche (silver-gelatin, diazo, and vesicular) - Dry gently with a soft, lint-free cloth.

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