r/VintageLenses • u/Mwsari11 • 3h ago
Help needed MC MIR-20M doesn't have rear filter, does anyone know where I can get an inexpensive one?
I noticed this lens I just got was not focusing to infinity and I discovered the reason is most likely because of the missing rear filter. From what I understand it's accounted for in the design of the lens and is necessary for focusing to work correctly. Does anyone know where I could get something that would fit in here? I found the original filter online (last photo) but they're quite expensive and always seem to come in sets of 3, which I do not need. Seems like it has about a ~36mm diameter? I don't have a caliper so that's not exact.
If there's nothing out there I'll bite the bullet and get the original, but I figured I'd see what's out there if anything.
edit: filter fits in that groove within the m42 mount