The Mark III edition of this Canon 1.4x Extender, or teleconverter, is the latest (and probably last) in the EF-mount series, designed for Canon cameras and compatible EF-mount Canon telephoto lenses.

Canon's two new EF extenders are direct replacements of the current extenders offered by Canon as essential accessories for professionals. These new extenders have been designed to provide faster ...

Just like with any 2x teleconverter, the focal length of the attached lens is doubled, with a consequent aperture reduction of two f/stops. As such, a 70-200mm f/2.8 zoom effectively becomes roughly a ...

We spend a day shooting aeroplanes with Andy Rouse to test the new Canon EF 200-400mm f/4L IS USM Extender 1.4x lens. The Canon EF 200-400mm f/4L IS USM Extender 1.4x is a professional quality ...

Canon's EF 200-400mm f/4L IS USM Extender 1.4x ($10,999) is a behemoth of a lens that ships in a hard carrying case. It's not a good choice for the weak of back, but its optical performance is superb, ...

This month will see the release of Canon’s EF 200-400mm f/4L IS USM Extender 1.4x lens, the first super-telephoto zoom lens to incorporate an internal extender. Side view of the new Canon’s EF ...

Canon’s EF 200-400mm f/4L IS USM Extender 1.4X more than satisfies the requirements of its target market. Sports and wildlife photographers should be delighted by the convenience of the built-in ...