Canon ef 400mm f 4 do is ii usm vs sigma 500mm f 4 dg os hsm sports?

Both are f/4 primes for full frame, both are stabilised and autofocus, so the choice mostly comes down to reach and mount.

The Sigma gives you 500mm against the Canon's 400mm, so pick it if you need the extra reach for birds or distant animals. It also fits Nikon F as well as Canon EF, so it's the only one of the two that works on a Nikon body. The Canon makes sense if you shoot Canon and 400mm is enough. On an APS-C Canon, it frames like about 640mm, while the Sigma frames like about 800mm.

If you want something lighter, the Sigma 500mm f/5.6 DG DN OS Sports is a comparatively light 500mm prime for wildlife. For help with reach in general, see Wildlife and sport, and if you're comparing prices, read buying used.

Written by Claude from this site's pages.