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 ...
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, ...