Hi lovejaca,
I've used basically the same setup, however, on a equatorial mount.
I don't know if this will fit on a fork mount.
This is an image I found, not my setup.
- Focal reducer
- Celestron T adapter, M42 thread with 50mm optical length
- M42 to M48 adapter (you cant see it in the image)
- M48 16.5mm is the optical length of the OAG. So replace the 16.5 spacer in the image with your OAG
- M48 21mm spacer (This could be replaced with a filter wheel, they are 21mm also)
- M48 11mm spacer.
- 6.5mm camera back focus.
So, 50mm +16.5mm(OAG) + 21mm + 11mm + 6.5 camera back focus = 105mm
Take care, if you have a filter in the optical path that this will reduce the optical length to 1/3 of the filter glass thickness. For example a 3mm thick filter glass is the same a 1mm through air, so the camera will need to be 2mm further away from the focal reducer.
I hope this helps.
Steve.
