I know a guy selling a Pentax 1.4 prime lens. The aperture stick at f16 and needs a tap or needs to be turned past 16 which will cause it to close up as it should.

The lens is 30 years old and has sat for a long time. Does this sort of problem typically resolve after use or a harbinger to total meltdown? Typically of course. For those still photographers out there who might know.

It's only $40, and I'll only use it wide open.

Feel free to speculate.

I'd don't know about Pentax but I had a Nikon 50mm 1.4 that had a stuck aperture. After I had a technician open it up and clean the lubricant it was great. These tend to stick as they grow older. Check how much it would cost to service. 1.4 is razor thin and f/16 is deep it might drive you nuts when used indoors.

Working m42 mount 50/1.4's are not hard to find, so why not look for a better one. I have several and all were under $40-.