Hello Samantha!
Thank you for posting your question. I think your hesitation to use a solvent on the emulsion is correct. You may already be handling these with nitrile gloves, but I recommend doing so if not. This will protect both the emulsion and your hands from the grime. Without seeing what sort of debris or grime has accumulated on the surface, or what era of transparencies you have, I would recommend being cautious. The first step I would take is to identify the emulsion side and avoid contact with it. If it appears flaky or otherwise damaged I would not attempt cleaning it. Assuming the emulsion side is stable, you may want to lightly swab off accumulated grime from the surface with a very soft lint-free microfiber cloth (the kind for eyeglasses). If you do this, do not wipe, but gently dab to see if any dirt comes off --and not on the emulsion side. It is possible to scratch the polyester or acetate support. I would also recommend dating the slides to rule out nitrate base before proceeding.
https://psap.library.illinois.edu/collection-id-guide/slide#bwfilmslide might be helpful.
If you find that cleaning is necessary to capture a faithful image, or it is too delicate and time consuming for your resources, vendors who would provide conservation treatment and digital imaging might be a good solution.
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Elizabeth Stone
Collections Conservator
University of Iowa Libraries
Iowa City IA
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Original Message:
Sent: 08-01-2023 19:43
From: Samantha Richert
Subject: Cleaning dirty slide transparencies
We have a collection of very dirty slide transparencies that need to be cleaned before digitization. What is the best way to go about it? Looking on conservation supply websites, I see blowers, brushes, even a chemical called PEC-12. It makes me nervous to think about applying a chemical to film emulsion. Is it safe? Would brushes scratch the film surface?
Samantha Richert
Museum Curator
North Cascades NPS Complex
7280 Ranger Station Road
Marblemount, WA 98267
360-854-7343
preferred pronouns: she/her/hers