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History of Medicine

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Two books spanned open with spines touching. Emergency Preparedness and Response

Collection Recovery Methods: Photographic Materials

Photographic Materials include black and white or color prints, negatives, slides, and transparencies.

Black-and-white photographs on plain paper or mounted on paperboard   -   Black-and-white and color photographs on RC paper (resin-coated or other type of plastic-coated paper)   -   Photographic transparencies and film negatives


Black-and-white photographs on plain paper or mounted on paperboard

Recovery Priority during the first 24-48 hours

  • Dry or freeze within 48 hours.
  • Gelatin image surfaces swell and soften when wet. Avoid touching image.
  • Handle image by edges and support underneath.
  • Do not touch sticky image surfaces with bare hands. Do not tightly compress items.
  • Paper photographs will fuse together permanently if allowed to dry in contact with each other.
  • Cover them with plastic to prevent partial drying until they can be frozen or salvaged. Image surfaces are susceptible to mold and physical damage, especially at high temperatures.
  • Local commercial photo labs that offer traditional photographic processing may be used to rewash and dry black-and-white photographs on plain paper or mounted on paperboard.
  • Use extra caution with large objects; wet paper is easily torn. Support with screens or polyester webbing.

Freezing Procedures

  • Keep wet until dried or frozen.
  • Pack small batches inside plastic bags inside containers, or line containers with plastic to prevent uneven drying if there is a delay prior to freezing. Avoid tightly compressing photographs.
  • Pack oversize items flat. Pack rolled items separately and only one layer deep to avoid crushing.
  • Image may be freeze dried.

Air Drying Procedures

  • Rinse soiled or adhering items in cold water.
  • Drain excess water and lightly blot non-tacky image surface with absorbent material.
  • Separate and place face up on an absorbent material to air dry the front; turn over onto a clean dry surface to dry the back.
  • Prints 8x10 inches or smaller can be hung using clothes line and clips at one or two corners. (Wick water from an edge with absorbent paper to speed drying.)
  • Once prints are nearly dry, place the prints between blotters and in stacks to avoid distortions.
  • Place freezer paper on any tacky surface to avoid sticking to blotters. (Any unwanted fibers can usually be wiped off with dry cotton balls after the print is thoroughly dry.)
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Black-and-white and color photographs on RC paper (resin-coated or other type of plastic-coated paper)

Recovery Priority during the first 24-48 hours

  • Immediately dry; freeze if there are too many to dry within 24 hours.
  • RC paper photographs will fuse together permanently if allowed to dry in contact with each other. Cover them with plastic to prevent partial drying until they can be frozen or salvaged. Image surfaces are susceptible to mold and physical damage, especially at high temperatures.
  • Local commercial photo labs that offer traditional photographic processing may be used to rewash and dry black-and-white and color photographs on RC paper .

Precautions: Handle carefully; gelatin image surfaces swell and soften when wet. Do not touch sticky image surfaces with bare hands. Handle slides by mount edges. Do not tightly compress items.

Freezing Procedures

  • Keep wet until dried or frozen.
  • Pack small batches inside plastic bags inside containers, or line containers with plastic to prevent uneven drying if there is a delay prior to freezing. Avoid tightly compressing photographs.
  • Pack oversize items flat.
  • Pack rolled items separately and only one layer deep to avoid crushing.
  • RC paper photographs may be freeze dried.

Air Drying Procedures

  • Rinse soiled or adhering items in cold water.
  • Separate prints and place face-up on an absorbent material to air dry the front.
  • Prints 16x20 inches or smaller can be hung using clothes line and clips at one or two corners. (Wick water from an edge with absorbent paper to speed drying.)
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Photographic transparencies and film negatives

Recovery Procedures during the first 24-48 hours

  • Generally stable. Dry or freeze within 48 hours.
  • Bare films will fuse together permanently if allowed to dry in contact with each other. Cover them with plastic to prevent partial drying until they can be frozen or salvaged. Image surfaces are susceptible to mold and physical damage, especially at high temperatures.
  • Local commercial photo labs that offer traditional photographic processing may be used to rewash and dry photographic transparencies and film negatives.

Precautions: Handle carefully; gelatin image surfaces swell and soften when wet. Do not touch sticky image surfaces with bare hands. Handle slides by mount edges. Do not tightly compress items.

Freezing Procedures

  • Keep wet until dried or frozen.
  • Pack small batches inside plastic bags inside containers, or line containers with plastic to prevent uneven drying if there is a delay prior to freezing. Avoid tightly compressing photographs.
  • Pack oversize items flat.
  • Pack rolled items separately and only one layer deep to avoid crushing.
  • Photographic transparencies and film negatives may be freeze dried.

Air Drying Procedures

  • Rinse soiled or adhering items in cold water and then drain and wick excess water.
  • Separate and place face up on an absorbent material to air dry the front; turn over onto a clean dry surface to dry the back.
  • Film can be hung using clothes line and clips at one or two corners. (Wick water from an edge with absorbent paper to speed drying.)
  • Water trapped inside slide mounts will drain out if placed vertically. Paper slide mounts will take longer to dry than plastic ones. Slide mounts may require mold remediation procedures once dry.
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Last Reviewed: August 22, 2018