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 ...
Looks like Canon is preparing one of its most versatile professional telephoto lenses yet. A newly published patent suggests Canon is developing an RF 300mm f/2.8 L IS USM with a built-in 1.4x ...