C3 26000 pro backfocus distance?

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deleted avatar
I have a new C3 260000 pro with a Moravian 9 position filter wheel.
Anyone know the back focus for this combo?
From the manual it should be 47.5 mm or 41 mm (depending I guess on the M68 adapter?) but I need confirmation from other users.
The reason I ask is because I have some star elongation that it’s harder to diagnose.
I eliminated tilt in the imaging train by using only threaded connections, so I need to know the back focus is not the issue.

My imaging train consists of a FT 3.5 focuser, extender, field flattner, extender, FW, camera. All threaded connections
deleted avatar
PS: I received a quick response from Moravian.The new cameras are shipped with the new M68 adapter, so the BFF is 41 mm not 47.5. 
This explains my problems.
Mr. Pavel at Moravian Instruments was very helpful!
Well Written Concise
Bob Lockwood avatar
I know you already have the answer, but Moravian shows this on their website with the new 68mm adapter.
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