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reaching focus with focal reducer and external foc

Started by John999R, 01/22/2013 07:43PM
Posted 01/22/2013 07:43PM Opening Post
I have a CPC1100 and recently installed a Celestron f/6.3 reducer for visual use. The optic train also includes a William Optics focuser that I really like because it solved the image shifting associated with the OTA's focuser. However, I cannot now reach focus and I don't know if there is anything I can do about it because I've been told the eyepiece has to be approx 100mm behind the focal reducer to reach focus. That means I need to reduce the distance and I don't see any resolution without removing the WO focuser and replacing it with a shorter extender. I did that and was able to reach focus down to almost an 11mm EP. Still not satisfactory in my book and I could reduce the distance more if I could find an extender/adaptor that is shorter by about 3/8". If I were able to get down the additional 3/8" I hope this would enable the scope to reach focus with a range of magnifications, otherwise I'm simply going to remove the reducer and put the scope back to the way it was with the WO focuser. As much as I like the increased field of view and flatter field, I want to maintain the flexibility of having the dual speed focuser and no image shifting.

I suppose my question is has anyone installed a reducer and was still able to reach focus with an external focuser like the WO I have? Seems like an impossible task since you have to stay within 100-105mm distance from reducer to EP. One other thing I neglected to mention and I didn't try the set up without the diagonal, I think doing that reduces length some more, but at the same time adds viewing comfort problems at higher degrees.