If I'm not mistaken, the idea that taking a picture steals one's soul or part of a soul was independently arrived at by a number of different cultures in contact with modern Western technology. Certain American Indian tribes believed this, and I seem to remember a similar story from Papua New Guinea, among others.
I suspect these cultures all had an idea that knowledge of a person's name or likeness was sufficient to cause them harm through magic - voodoo uses this principle, for example. A photo is a likeness, but it's a very good one, so it's something to watch out for.
Arthur C. Clarke's maxim "Any sufficiently advanced technology is indistinguishable from magic" holds here; a camera would be like a voodoo cheat sheet to a culture that believed making a doll of the person would be able to cause them harm.