You asked
Best telephoto lens for the olympus pen e pm2?
For the PEN E-PM2, I'd start with the OM System M.Zuiko 50-200mm f/2.8 IS PRO. It frames like 100-400mm on full frame and stays bright at f/2.8, which matters for wildlife and sport in poor light. It's a big, serious lens, so expect weight.
If you want more reach for less money and bulk, look at the Panasonic Lumix G 100-300mm f/4-5.6 II. It's light, and it frames like 200-600mm on full frame.
For the longest reach, the OM System M.Zuiko 150-600mm f/5-6.3 IS goes to 300-1200mm equivalent. It's slow at the long end, so it suits bright days and distant subjects best.
The camera's in-body stabilisation helps with handheld shooting. For more on choosing, see wildlife and sport, and check the full PEN E-PM2 lens list for everything that fits.
Written by Claude from this site's pages.