Film shrinkage in many film gauges is also a common type of film decay. For example, if you have a piece of 16mm film and you put it through a film shrinkage gauge (see page 15 of The Film Preservation Guide), and the film measures less than 16mm wide, then you have shrinkage. This is pretty self-explanatory, but it is an important consideration. Shrinkage is one of the reasons why archivists do not use film projectors to inspect film. If you put shrunken film through a projector, the sprockets could puncture holes into the film, which is something that cannot be easily repaired. Color fading is another common type of decay. If exposed to heat and humidity or poor processing, the chemical dyes in the film will lose color. Digital technologies can help to restore some color, but not necessarily to its original state, so it is always best to keep films in stable air conditioned environments to prevent this from occurring.
If you’re interested in more information, be sure to check out the National Film Preservation Foundation’s “The Film Preservation Guide.”
This week I want to talk a little bit more about film and its chemical changes over time. I talked a little bit about this in my first post, Introduction to the Collection and Project, but I wanted to elaborate more on different types of decay that films face. Margie Compton pulled out some films for me in order to present examples of the types of damage and decay that occur in film, which are described below in the slideshow.