Rings or?

[LewisM]

I have a Vixen VC200L. The ONLY way it will balance in DEC with a camera attached is to use a honking big Losmandy rail (custom modified by the original owner - I am owner 3 :) ) - there is simply NO WAY it will balance with the original Vixen rail in DEC - just way too much weight out the butt end (how Vixen expects anyone to balance the VC200L with their stuff is beyond me - even with NOTHING attached to the drawtube, it was butt heavy, and that was with the rail at it's rear stop!).

The Losmandy works well, - VERY well in fzct, and it does have central holes so as to mount rings if wanted instead of the custom modified cradle supports. I have a set of 200mm rings that will work - is the ring system attached to the Losmandy going to afford me overall better service and security than a Losmandy with cradle? The support points will be almost identically spaced regardless of system used, but will the total circumference security mean much? It is ROCK SOLID as-is.

The other thing about using rings is if I decide to, I can of course add a top rail and add my ED80 as guidescope (going to use an Orion mini-guider finderscope for the time being) - only would necessitate removing the carry handle and finder.

MAGICAL scope - just a tad out in collimation - just have to figure out if it is the primary, secondary or the flattener/focuser off whack a little. It's not MUCH, just a slight left shift (fine for visual, NOT for photography)

[Tandum]

I had one a few years back and it balanced ok (http://starshed.net/gallery/displayimage.php?pid=19&fullsize=1) with a canon on the arse end.

Try a GSO RC8, you have to hang a brick off the front of it :)

[gbeal]

Use the rear end heaviness to your advantage.
Mount the guide-camera etc under the front section, using the rail. That assists with the problem, and also keeps the weight closer to the pivot (RA axis).
Gary

[DavidTrap]

Hi Lewis,

There are many posts on the web that suggest using rings to reduce flexure of the tube to help maintain precise collimation. If you've got them and they fit, I'd be using them.

As for the collimation, I'd suggest trying to adjust the primary mirror first. In addition to following Vixen's instructions, I used a laser collimator to align the focuser and secondary, so they're probably pretty close.

All the best,

DT