Sony FE 400mm F2.8 GM OSS

Reviewers rank it among the sharpest super-telephotos on any system. It is excellent wide open across the frame, colour fringing is practically absent, and it keeps very high quality with the 1.4x converter. Background blur at f/2.8 is smooth and the subject separation is something slower lenses cannot match.

Autofocus is consistently described as instant and silent, with tracking limited only by the camera body. The criticisms are price, size and the fact that newer, lighter designs such as the 300mm f/2.8 GM and the 400mm f/4.5 GM now cover some of the same work for much less.

Owners are mostly working sports and wildlife photographers, and they report very high keeper rates and a lens that stays reliable through heavy use in bad weather. The balance, the carbon-fibre hood and the controls at the front of the barrel get regular praise.

The complaints are the cost and the size: it needs a monopod or gimbal for long sessions and a dedicated bag for travel. Some note that the supplied hard case is bulky and that Sony's US price has risen since launch.