My happy place. In my back yard. 2017 I used a 100mm lens that I bought in 1983. For quite some time the aperture has been stuck wide open on this lens. The other day I decided to look it up, and sure enough, it is a common problem with old lenses. However, YouTube University to the rescue! I found several videos on how to dissassemble and fix the problem! Now this old lens is back in rotation!