Originally posted by mikeSF thanks, sounds like this is what happened. Any idea how much it will cost to get it repaired? i obviously cannot do something like this myself.
I have no idea how much it will cost but probably a standard fee like $120? However, something like this should never happen and you might get lucky with CS. If the dropped front section and the focus ring aren't damaged, you can just put them back together and it will be good as new.
1) Unscrew the front metal retaining ring (on the filter ring) with a piece of rubber (the ring is not tight but getting a good grip can be tricky). You can also get the proper rubber tool on eBay for a few bucks only.
2) Remove 3 small screws that holds the filter ring.
3) Remove the hood.
4) Assemble the focus ring.
5) Assemble the front section and make sure the front lens group is not loose (screw tight by hand will do).
6) You should be able to see the screw marks on the focus ring, just line them up and put back the screws.
7) Check infinity.
8) Threadlock the screws.
9) Assemble the hood and everything else (remember threadlock all screws with low strength threadlock and let them cure for a week at least b4 use).
PS: These are off my head so if the fragile contact brush was damaged, then you will have to send it in.