Out of the box, I had to adjust the pre-load on the two speed focuser, but this is pretty much the same as with my SV 110ED, which appears to use the same focuser, though it has the ability to rotate, and the Lunt one does not.
Anyway, I have not had any issues with using the focuser with the binoviewer, but the Maxbright is super-light, and Ionly use a single pair of eyepeices (Vixen NPL Plossls) for 100% of my Ha observing. I find that this magnification gives the best balance between full disk, prominances, and surface detail (the Lunt 60 can't really resolve detail in the penumbra of sunspots when tuned off band, so going higher does not bring out any new detail in these features).
With the 15mm Plossls, I get about 50x I think? Something like this.
Anyway, the focuser has not given me any problems but again, I did have to slightly tighten the preload on the two speed unit, but mostly that was when I was trying out Baader Zoom eyepecies (heavy.. Did not like using them in this scope.. Could not use winged eyeguards).
Remember, you have to use a GPC. I am using a 1.25x GPC mounted in front of the BF-1200. I did a post about 7 or 8 months ago on the binoviewer forum on how to do this.
You can also use a bigger GPC in the normal location of course, and there are other ways to get there, but for me, the Maxbright is dedicated to this scope, and part of the reason I like this configuration is because it does indeed reduce the load on the focuser by having it directly mounted the same way that it would mount to a T2 diagonal.
The BF-1200 is of course T2 already, so the Maxbright just screws on. But you need one adapter to mount the GPC in front of the BF the way I did it. PM me if you have any questions.
Edited by Eddgie, 11 October 2014 - 08:25 AM.