I get asked every now and then how I make a determination if someone’s film needs more advanced preservation or not. I decide this based on a subjective test and an objective test. The subjective test I use is that I look to see If the film is curled up any at all or if it is brittle. The objective test I use are AD Test Strips from the Image Permanence Institute and see how much “hidden deterioration” there is.
As film deteriorates it emits an acidic vapor which becomes a double whammy as it destroys more of the film. The more green/yellow the strip turns the more aggressively we pursue advanced preservation techniques.
Treasure Coast Film 