Tripod Collar for 200L f/2.0

ed rader wrote:

:-).

i'd use a tripod collar if you are changing orientation while shooting and don't have an L bracket.  i actually have a used OEM canon tripod collar in black that i would sell to you if you decided you need one.

I appreciate the offer, Ed. Did a search on Amazon and it wasn't clear which collars worked and which would not.  My application, for tripod use, is mounting on a Vixen Polarie tracking mount to do astrophotos. The set up is: Tripod > Manfrotto Geared Head > Polarie aligned with North Pole > Ball mount > Canon 60Da > 200L f/2.8 (or other, all smaller, lenses like 50 f/2.8 II).

Once aligned Polarie is North-aligned, and camera is pointed to area to be photographed (say Orion Nebula) then the motions of the camera-lens will basically be the Earth's rotation rate -- very slow so minimal accelerations at the interface.

Likely I'll try it and if there are stability issues I'll look into a collar. Total load in lbs is limited to 2 kg (4.4 lbs) and with the ball mount, 60Da and 200L my total is 4.2 lbs, leaving 0.2 lbs for the collar.

Problem is that I won't get to test this until Nov.  My daughter is taking my Polarie, tripod, geared mount and ball mount and her 40D to AZ tomorrow. She should do well there with dark skies. Here (metro L.A., near the ocean) I have much light pollution to fight and misc. issues from moisture in the air. I do have an Astronomik CLS clip-in filter arriving from Oceanside tomorrow so I'll probably do a piggyback on my C5+ or just do some short shots from a fixed tripod to see how it all works before Nov.