Focuser & Rotator with less than 52mm of backfocus

[RyanParle]

Hi all, I am in the middle of striking a deal on an Officina Stellare RH200 Astrograph, provided that the deal goes ahead i'd like to have an instrument rotator and motor focus. so I am looking for a rotator and focuser (either combined or separate low profile units) that will fit my application. so far I've not found anything.  here are the constraints I have regarding backfocus etc.

Astrograph backfocus: 105mm (from backplate)

Camera backfocus: 44mm + OAG: 9mm = 53mm

This leaves 52mm to somehow squeeze a rotator and focuser in to, then taking into account that I will need a few mm each side of the focal plane its probably safe to say that the thickness of the rotator and focuser (fully in) should be no more than 50mm. 

The Standard focuser is 40mm -55mm so doesn't leave room for any additions in the focal train.

Can anyone suggest any kit that would fit in the space i have available?

 

[Davey-T]

I remember quite a few reviews of this scope on CN when it first appeared so be worth browsing those, also I think Massimo Riccardi the guy that designed it is active on CN.

I imagine that focus, imaging train tilt is a bit critical maybe a rotator isn't such a good idea.

Dave

[RyanParle]

Ok that is worth keeping in mind, The backplate has Tilt/Tip adjustment, but I guess that if the sensor is mounted slightly of plane rotating the camera would negate these adjusters.

Initially I was thinking of having the rotator to ensure a good guide star could be found but with such a fast optical train i suppose it probably wont be an issue, however it would still be nice to frame objects nicely on the sensor. I currently have the scope in my possession so will experiment without a rotator and see how critical the rotation of the camera is... that is of course if we get a clear night.

I would still like to find something that will fit if possible.

[Davey-T]

Just had a look on CN and it appears other folk had similar problems, didn't read far enough to see if they found a solution.

Dave

[Starflyer]

Would an FLI focuser fit?

http://www.flicamera.com/focusers/index.html