Slide Film - Aging and Fading
I've been going through our old family slides recently trying to get a handle on how they are holding up. Some of these date back to the mid-1950's. Some non-Kodachrome slides that faded to pink more than 40 years ago, are, of course, still pink, although the majority of them sure look thin like they were very over exposed.
One roll from 1964 of non-Kodachrome (I have no idea what film it was, but with no visible emulsion so it can't be Kodachrome) has turned real smoky gray. In trying to restore the color by non-analog means, the grain appears to be huge.
I came across at least two other rolls from 1978 and '79 that I'm fairly certain were shot on K-Mart Focal slide film, and these not only have a magenta shift, but a very strong blue shift. It looks like the blue shift has also caused a general overall darkening of the images like they are all at least one stop underexposed. The grain in this film is golf ball size. Why I ever shot vacation pictures on K-Mart film instead of Kodak is beyond me.
So it looks like I have identified at least 3 types of fading: some to pink, some to smoky gray, and some mostly to blue with a little pink thrown in. Are there other fading/aging issues that I haven't discovered yet? Does grain increase as film deteriorates?
One other aging issue that I'm still trying to verify is if some colors turn rather muddy over time. I have some Kodachromes from around 1974 that were not processed by Kodak and they have a strange overall muddy look, kind of hard to explain, but maybe like they were shot late in the day, overcast, under exposed, with a lot of smog. Has anyone else experienced this with Kodachrome? Most of the Kodachromes much older look just fine, but these look odd.