Best telephoto lens for the olympus om d e m1 mark iii?

For the E-M1 Mark III, I'd look at the big Micro Four Thirds zooms first. Remember that every lens here frames at double its focal length.

• Olympus M.Zuiko 150-400mm f/4.5 TC1.25x IS PRO: like 300-800mm on full frame. It's the fastest of the long lenses here, so it's my pick if you can carry it.
• OM System M.Zuiko 100-400mm f/5-6.3 IS II: like 200-800mm on full frame. A shorter reach that's easier to live with day to day.
• Panasonic Leica DG 100-400mm f/4-6.3 II: like 200-800mm on full frame, another solid alternative in the same range.
• OM System M.Zuiko 150-600mm f/5-6.3 IS: like 300-1200mm on full frame, for the longest reach in the list.

For choosing between them, see wildlife and sport.

Written by Claude from this site's pages.