Heard a noise when focusing my LX200...

Was trying to get the new CCD imager focused on my 10" LX200 classic and heard something fall inside the OTA. I peered into the end and see this metal ring sitting on the bottom center of the tube. See attached picture.
Luckily it was almost horizontal so it didn't touch the optical surfaces.
Was able to tape a magnet to the outside of the OTA to keep it from shifting about when I moved it indoors. It appears to go on the outside of the small tube in the center of the assembly as I see a groove on the end of it. Is it a mirror focusing stop or something?
I assume the corrector plate will have to be removed. Any guidance or directions on removal and cleaning of the optics, as you can see there is quite a bit of dust on them.

If this is a task best left to professionals, anyone in the Seattle area that works on these?

Thanks in advance.

Gordon

Attached Image:

I believe that is a retaining ring on the baffle tube. It is probably very easy to fix.

Remove the screws on the corrector assembly at the front of the scope, take the black ring off and look for a white mark on the corrector and front mount. It is important that you put it back just like it was. The mark on the corrector is small - about marker sized. Mine is in the lower right corner, your's may be located elsewhere.

Put the part that fell out back in and screw everything back together. You will need to collimate your scope before imaging again.


Hope that helped.


*edit* I just looked at mine - it doesn't appear that the ring goes on the front baffle - it could very well be placed behind the mirror. If you don't feel comfortable taking apart your scope then have someone who is more confident to do it.



Phil

Anyone have an idea where this ring goes? I'll hold off taking it apart until I know what it is.

Gordon

I was fortunate enough to get a email response back from Dr Clay and was informed that it is a mirror stop that belongs near the end of the baffle tube.
I reinstalled it, but it popped off again the first time I ran the focus from end to end.
Note: I did install a EZ-Focus upgrade a couple weeks ago. Maybe I'll revisit that and see if I can make it stop before hitting the end.
Unless someone has any ideas out there...