OK, that was fun. It wasn't fungus, just general detritus. So, my set up was a place mat, screwdrivers, 2 lens cloths, a microfibre cloth a torch and some strong glasses. The first thing I undid was the slotted ring on the back, this loosed the rear element. I made a mental note of which way it went in (round side to the rear) and shone a torch through it. It was dusty so it got cleaned. I then removed the three screws holding the mount and lifted it off. The A/M ring was loose so I lifted that off and didn't see where the ball bearing went! Doh! I then unscrewed and removed the aperture ring carefully, making sure I kept the bearing. These bearings are sat on a spring and click into slots on the ring to hold it where you moved it to! I then realised I needn't have taken the rings off, doh! So, moving back to the glass, I unscrewed the housing of the rear elements, they were finger tight, took them apart, noting which way up they went, shone the torch, saw the muck, cleaned each with lens fluid on a glasses cloth, polished with microfibre then polished with a dry lens cloth and reassembled. I managed to find the missing ball bearing with a large magnetic screwdriver. I now have another nice 28mm lens
OK, pictures. I took some test shots too and will post them once they are on flicker.
Edit:
OK, test shots, minimal processing
That'll do
The Beastie in bits
Last edited by Cerebum; 11-16-2020 at 05:01 AM.