As a 1.4x teleconverter, the focal length of the attached lens is magnified by a factor of 1.4x, with a 1 f/stop reduction in aperture rating, so a 70-200mm f/2.8 zoom effectively becomes roughly a ...

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 ...

Canon's EF 200-400 lens delivers terrific optics and unmatched zoom flexibility with an innovative built-in 1.4x telephoto extender. Stephen Shankland Former Principal Writer Stephen Shankland worked ...

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 ...

We've spent a little time with the new Extender RF 1.4x and Extender RF 2x for Canon's full-frame mirrorless cameras, so ahead of our full review, check out our first impressions now... The Extender ...

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 ...