Quote Originally Posted by AllanMarcus View Post
I have a Sigma 70-200 f2.8 monster, and an equally sized 135-400. In both cases the lens comes with a mount bracket to mount on a tripod. I use a bogen quick release and a bogen ball head and I have no problems since the center of gravity is "in the right place" when you use the included mounting bracket.

Thanks for the reply Allan. How does the alpha like these lenses?