I have a Kodachrome 40 Super 8 film cassette, which was exposed, developed and viewed using a projector in 1980. I have not tried to view/project the film recently. However, the film in the cassette now looks completely grey, with no sign of any developed images. Is this type of cine film affected by aging after it has been developed?
Kodachrome film, like color films, degrade with age. First the dyes that comprise the color image are organic in nature and their longevity, under the best of conditions is less than 100 years. In all likelihood they dyes have already degraded. Additionally, film uses a binder of gelatin to encapsulate the dyes and attach them to the film base. Properly process Kodachrome move film was over coated with clear lacquer that served to seal out moisture and protect the underlying delicate gelatin. Kodak labs and some independents applied this lacquer, some did not. To ease the film going through a projector, the edges were lubricated with mineral oil (again not all labs applied).
Now gelatin is also organic and a tasty meal for beasty such as mold and mildew. The mineral oil dries up leaving a residue, the dyes degrade, the film base become brittle. To protect the film, we store in cool dry conditions. Sorry to report that all color films will eventually be damaged given sufficient time. To archive these memories, best if you have the film copied and transferred to a digital media. Let me add, we don’t know what digital display devices will be prevalent in the future. For example, if I presented you with an 8 track music cassette, how would you play it? Bottom line, we do our best and that’s all we can do.