Stabilizing Wet Photographic Materials

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Contributors (alphabetically): Heather Brown, Luisa Casella, Jae Gutierrez, Barbara Lemmen, Amanda Maloney, Andrew Robb, Stephanie Watkins

Facts About Photographic Materials

  • Photographs are composite, laminate structures composed of supports, binders, and image material.
  • Binders, when present, and image materials combined are referred to as the image layer.
  • Common supports are paper, plastic, glass, and metal.
  • Common binders are gelatin, egg white (albumen), collodion (cellulose nitrate), gums, and starches.
  • Common image materials are silver and other metals (iron, platinum, palladium, etc.), organic dyes, pigments, and inks.
  • Different processes may appear similar to each other but can react differently in water. Digital prints are easily damaged by water.
    If time allows, RIT’s Graphics Atlas has a visual photo identification tool.
  • For triage approach, if unable to sort by image material, process groups of photographs by the support type (paper, plastic, glass, metal).

What to Expect When Photographic Materials Get Wet

  • Handle photographs by the edges without touching the image side, even when wearing gloves.
    Wet photographic surfaces are very easily damaged and dislodged.
  • Paper-based materials absorb water. When wet, paper becomes heavier and tears easily.
  • Plastic-based materials become more pliable and can be easily creased and scratched.
  • Color photographs may have a semi-opaque white-blue or pink tinge when wet.
    This usually dissipates once the photograph is dry. Avoid touching the image surface when wet.
  • Wet color dyes, studio stamps, signatures, and inscriptions may bleed and stain other, nearby materials or feather and sink through the photographs paper support.
  • Photographic materials, case and frame components (fabric, paper, leather and wood) may grow mold.
  • Framed photographs may stick to their window mats, frame spacers, the glass or plastic glazing as they dry.
  • Photographs in paper or plastic sleeves may stick to the sleeve.
  • Photographs in albums can stick to the adjacent pages.
  • Photograph supports can dry misshapen.
  • Image layers may separate, crack, or curl upon drying.
  • Photographs that get wet or stuck may have losses in the image layer and changes in surface gloss.

Salvage Priorities During Triage

  • Rare, unique photographs - salvage first
  • Photographic materials stuck to themselves or housing
  • Materials that are bleeding colors - separate, isolate as best as possible
  • Negatives, if the images can be reprinted
  • Motion picture film - freeze unless length can be processed safely
  • Paper-based negatives - freeze
  • Paper-based prints
  • Items that are replaceable duplicates, or items that are too far gone to salvage - salvage last

Drying Photographic Materials in a Triage Emergency Event

  • Freeze if quantity exceeds response time. Freezing is safe for most processes.
    Do not freeze cased, instant, digital, collodion negatives on glass, and rare color processes.
  • Wear latex or nitrile gloves.
  • Do not dry directly in sunlight.
  • Dehumidify and circulate interior air with fans.
  • Do not pull wet photographs from their protective enclosures. If possible, cut away the envelope or sleeve around the perimeter edges, then carefully peel the enclosure off at an acute angle while keeping the photograph flat.
  • Photographs stuck to plastic enclosures should be kept damp by wrapping in plastic. Seek conservation help as soon as possible.

PAPER-BASED

  • Air dry in a single layer, image or dull-side up on absorbent or screen materials.
  • “Quick-rinse” muddy items in a bucket of cool, cleanest available water.
    Skip rinsing step if the photograph is lifting or separating: Look closely along edges.
  • Do not touch the surface; do not blot off excess water.
  • If wet and stuck in a stack, gently peel apart at a low angle only if possible. Do not force separation. Some image loss may occur.
  • Use carrying supports for large or weak items.
  • Freeze in current housing if quantity exceeds response time (see FREEZING guidelines below).

CASED PHOTOGRAPHS

  • Open cases to slowly air dry.
  • DO NOT remove the photograph from the cases.
  • DO NOT open daguerreotype packages. (Daguerreotypes have a mirror appearance and are generally small, although they can be about the size of copy paper or legal tablets.)

PHOTOGRAPHS IN ALBUMS

  • Open albums to slowly air dry.
  • Sturdy albums can be placed upright, like a book, fanning out the pages for air access.
  • Dry flat albums that cannot be placed upright.
  • Avoiding the photographs, insert spacers (e.g. wadded paper, paper-towels, waxed-freezer paper), to allow air circulation between pages.
  • Reduce likelihood of double-sided album pages sticking by inserting waxed or freezer paper between pages before freezing.

FRAMED PHOTOGRAPHS

  • If photographs are wet within the frame, unframe carefully watching for any areas that may be stuck to glass or mats and air dry.
  • Don’t hang photographs in wooden frames to dry. Joints may be loosened from moisture.

PLASTIC FILM NEGATIVES

  • If muddy, rinse in cleanest water available. Dry vertically, if possible.
    Skip rinsing if photograph layers are separating (look closely along the edge).
  • Hang negatives on a clothesline with clothespins.
  • Use opened paper clips to “S-hook” negatives with sprocket holes onto clotheslines.
  • Air dry image/dull-side up flat on absorbent materials.
  • Do not touch the surface; Do not blot off excess water.
  • Freeze motion picture film and paper negatives if there is insufficient time for processing.

METAL, GLASS, CERAMIC-BASED PHOTOGRAPHS

  • Air dry slowly.
  • If muddy, rinse in cleanest water available. Dry vertically, if possible.
    Skip rinsing if photograph layers are separating (look closely along the edge).
  • If no other options are available, freeze glass plate negatives.

Freezing Photographic Materials in a Triage Emergency Event

  • Leave in original enclosures.
    If there are multiple photographic objects without individual enclosures, create stacks that are separated every few photographs with a release material like wax paper. Keep the stacks small – 1-2 inches (2.5-5cm) tall.
  • Place stacked photographs into a zipper storage bag.
    Push out as much air as possible before sealing and make sure each bag is well sealed.
    Place an additional zipper storage bag around the first.
  • Place into freezer. Cartons or crates require blast freezing.
  • When ready to air dry, remove bag from freezer.
    Allow the package to rest unopened at room temperature until thawed (usually a few hours). Large blocks are difficult to thaw.


More detailed information is available at PMG’s Emergency Response, Salvage, and Recovery Techniques page.