Paul
Thank you.
The Celestron motorized focuser works quite well once one fixes the problem inherent in the adapter plate that Celestron supplies.? And the fix is rather simple as shown in the video.? So, while the Feathertouch may be an excellent choice I have no problem recommending the Celestron focuser.
Yes, if the contribution to mirror flop from the focuser is eliminated then what remains is inherent to the fact that the mirror is not locked down in the Celestron SCT design.? ?Even the "locking knobs" on the Edge versions merely put a little pressure on the back side of the mirror mounting plate and do not actually lock down the mirror.? The obvious source of this is the play that is required in the baffle tube arrangement so that the mirror can slide forward and backwards during focusing.? You will see this and Dave's fix in the 3rd video which I still have to edit and upload.
Regards,
Curtis
