Canon EF 200-400mm f/4L IS USM Extender 1.4x is a telephoto zoom lens with a built-in switchable teleconverter.
The super telephoto lens is designed for professional sports and wildlife photographers and the EF 200-400mm f/4L IS 1.4x lens is currently priced at $11,999.
CameraStuffReview has posted a full review for the new Canon EF 200-400mm f/4L IS USM Extender 1.4x lens. The review includes sample images taken with the Canon EF 200-400 mm f/4 L IS USM EXT 1.4x lens mounted on Canon EOS-1D X camera, lens construction, image stabilization, resolution, vignetting, distortion, bokeh and flare.
Canon EF 200-400mm f/4L IS 1.4x Review
From CameraStuffReview review :
The Canon 200-400 mm performed in our test with the highest image quality we have come across for a Canon zoom lens, with and without the 1.4x converter. Flare and ghosts are incredibly well suppressed and in terms of resolution, the camera is likely to be the limiting factor. Professional sports, action, or nature photographers will quickly be convinced of the qualities of the Canon 200-400 mm f/4 with built-in 1.4x converter. Compared to lenses with a fixed focal length, the zoom range of 200 mm to 400 mm zoom delivers an excellent opportunity to frame precisely, while the picture quality remains high.
The sensational built-in converter prevents the laborious procedure of inserting a converter between a camera more than a kilo and a lens of more than 3 kilos. It prevents the frustration of missing just the right shot, because you were inserting a converter between the lens and the camera. The fact that under damp and dusty conditions you need to change the lens as little as possible is also important in order to maintain the highest image quality.
Canon EF 200-400 f/4L IS USM 1.4x Price and Availability