I once had to open an old 24mm Pentax lens that my parents handed down to me when I started photography. The aperture was stuck due to some old grease, and with

I once had to open an old 24mm Pentax lens that my parents handed down to me when I started photography. The aperture was stuck due to some old grease, and with that the lens barely unusable. The fix was pretty easy, and the whole process of understanding all the tiny mechanics of a lens were a lot of fun, but at the same time it was incredibly stressful to have those optical elements so exposed. I couldn't image doing the same thing with a current lens that also has all those electronics in there.