Has anyone had luck taking this lens apart without affecting the focusing plane and such? I've never taken a lens apart but the focusing ring on mine has clearly a bunch of dirt and junk in there as the auto focus barely can function and manually focusing sounds like a lot of dirt.
It is the first gen f/2.8, I found a video that shows taking apart the front element but not sure on the focusing ring. Any suggestions? The front element is pretty pitted as well but I don't think there is anything I can do with that as its the glass. It doesn't seem to be affecting the IQ
