u/preposterousprops

I'm looking at a spare lens I've had laying around (but never used) and seeing that it is labeled with two different focal lengths and two different sets of f-stops. Can someone explain how this is possible, and how I would switch between them, if that's what is implied? Thanks

I frequently get a lot of these types of artifacts, which I think come from the developing stage but I can't identify the problem. It seems worse on hot days but will also happen when I have cooled the developer down. Does anyone have experience with this or advice? Thanks!