I guess it does help if I add the remainder of the post DOH!
so ...
I also want to use my 2" Televue Powermate 2x for which I also have the T-ring adapter. My question is what amount of back focus do I need from the Powermate T-ring adapter? From reading the Televue website and a very brief chat to Al Nagler himself from TeleVue in New York I understand this to be 2" (56mm) to the imager. Is this correct or do I need to still work the powermate in with the 146mm stated by Celestron?
Thanks in advance and clear skies!