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if a leak is showing on the bottom of the frame on a photo, the leak will be coming from the top in camera as it's upside down?
Basically yes, if it's like a common leak due to light seals of the back door being in poor condition or similar.
I've also had a few ones that were more tricky to figure out where they came from (like when my Mju-II got knocked a bit too much and apparently some light was entering from the front, around the lens somewhere).
Check the seals, use camera with case / without, take a mental note when you shot two frames in quick succession or with a gap (and a lot of light hitting the camera) in between, and you should be able to figure out what's up.
Light leaks- if a leak is showing on the bottom of the frame on a photo, the leak will be coming from the top in camera as it's upside down? Is that right?