You asked

Best camera for the leica apo vario elmarit sl 90 280mm f 2 8 4?

This lens is made for full frame, so I'd pair it with a full frame body. Any of the bodies on its catalogue page will work, and it's stabilised, which helps when you're zoomed to 280mm.

The Leica T, TL, CL and TL2 also take this lens, but they are APS-C, so it frames tighter there (roughly 135-420mm). That can suit wildlife, but you lose the wide end. If you're unsure, lenses explains how crop factor changes what a focal length does.

Written by Claude from this site's pages.

From these pages