g__day
15-02-2008, 12:46 AM
Well through Scope Stuff in the USA I got a $32 adapter to mate the annoyingly obtuse thread they put at the back of their MAKs - to a standard 2" SCT thread.
From Bintel I got a $129 2" 10:1 fine focsuer for a SCT - nice piece of gear really.
Of course challenge 1 - the 2" SCT focuser base is so wide I thought it wise to remove the focuser on my 127mm Skywatcher MAK - it was a tight fit.
Secondly the mating collar from Scope Stuff is I'd guess 1/2 and inch long - with 2" thread on the last 1/4 inch. The back of the BinTel focuser has about a 1/4" of 2" diammeter thread before it widens. Put the two together and the back of the focuser falls of the thread 1/4" before it touches the rear of the OTA...
Off to hear Fred Walkers talk in North Ryde - and race home with an idea - cut a 4mm wide Nylon zip tie and wrap it around the unthreaded base of the mating collar to act as a non-crompressible spacer - perfection. Go to super glue the ring - glue is gluggy - why wasn't I surprised! Sticky tape it on - rush out before the rain returns - perfect fit!
Realise the base of the focusing tube will just fit with 1mm clearance - but have to dismantle it all to re-attach things!
Got it all set up - had time to point it to Alpha Centuri for 45 seocnds before the rain came. Just enough time to rough focus it then start fine focusing!
So its a success - but a surprise. It's been ages since I did visual observing through the MAK. I had real trouble bringing it into sharp enough focus to split this binary. It seemed to turn forever to lose focus - but reversing it into the sweet zone didn't hit spot on focus - any ideas why?
Matthew
All good - no, strike that - great - in the end
From Bintel I got a $129 2" 10:1 fine focsuer for a SCT - nice piece of gear really.
Of course challenge 1 - the 2" SCT focuser base is so wide I thought it wise to remove the focuser on my 127mm Skywatcher MAK - it was a tight fit.
Secondly the mating collar from Scope Stuff is I'd guess 1/2 and inch long - with 2" thread on the last 1/4 inch. The back of the BinTel focuser has about a 1/4" of 2" diammeter thread before it widens. Put the two together and the back of the focuser falls of the thread 1/4" before it touches the rear of the OTA...
Off to hear Fred Walkers talk in North Ryde - and race home with an idea - cut a 4mm wide Nylon zip tie and wrap it around the unthreaded base of the mating collar to act as a non-crompressible spacer - perfection. Go to super glue the ring - glue is gluggy - why wasn't I surprised! Sticky tape it on - rush out before the rain returns - perfect fit!
Realise the base of the focusing tube will just fit with 1mm clearance - but have to dismantle it all to re-attach things!
Got it all set up - had time to point it to Alpha Centuri for 45 seocnds before the rain came. Just enough time to rough focus it then start fine focusing!
So its a success - but a surprise. It's been ages since I did visual observing through the MAK. I had real trouble bringing it into sharp enough focus to split this binary. It seemed to turn forever to lose focus - but reversing it into the sweet zone didn't hit spot on focus - any ideas why?
Matthew
All good - no, strike that - great - in the end