Reply To: Cleaning 35mm slides


gelatin based film shouldn’t be cleaned with no water included solution if possible.

Actually I don’t think that liquid based cleaning should be performed at any film except you can be sure the external gelatin layer is in really good shape, and for that its necessary to have a well trained eye in the subject.

Fungii presence is one of the reasons that can justify the use of liquid based cleaning methods, but in the other hand fungii and direct contact water damage are the causes of gelatin weakness that can produce, when cleaning with solutions, the loss of the binder and so the loss of the image. Advanced fungus deterioration of water damage will leave the gelatin layer in really bad shape and the mechanical action of cleaning can be the loss of it, if you also do it with a wet cotton, you can imagine…

Sometimes the fungii we see in old film is only the traces of inactive one produced a lot of years ago. Sometimes is removable, sometimes not, but the use of solvents of any kind can also leave traces in the binder, and some of them are really dangerous and must be used with mask, protection glasses and air extraction devices.


So I think that my opinion is like “if you are not really well trained in evaluation damage and integrity and you cannot hire a trained conservator to do it, try to keep the liquid based treatments far from your films” even if the use of cleaners are really extended in the States and a lot of people found it really normal and safe. Gelatin can pass from “perfect shape” to “very weak” really fast and without not too many signals, and you will notify in the works of ways.