I have in my home some very old photos of ancestors, some going back 120 years or so. I don't know much about film, but they are mainly from the 1890's to right before British involvement in World War 1. Some of the photos were taken in Britain, some in the united States, and others in Africa by British equipment (I don't know if that means they are on different types of film). They are mostly backed on hard cardboard or postcards, although one isnt a print so much as an image stained on a piece of metal. There is also a collection of photos taken by my American great-grandfather during World War 1 at the front, these are on a much thinner type of print and tend to be more faded.
I would like to scan them to find out more about my family, like what the insiginia they wore meant etc., but not at the price of losing them completely. I also thought this might be a good way to preserve them