1-770-333-4200. Description. The Canon 1.4X EF Extender III is a professional grade teleconverter designed exclusively for use with select Canon brand L-Series lenses (focal lengths over 135mm). Extending a lenses focal length by a factor of 1.4x, Extender EF 1.4X III incorporates incorporates careful lens placement and state of the art
WaddizzleLegend. 11-05-2020 09:57 AM. If you want a teleconverter for an EF mount lens, then you must use a teleconverter for an EF mount lens. If you wish to. Use an EF mount lens on an RF mount body, then you must use an EF-RF mount adapter. I am not aware of a single device that can do both functions.
There were some folks that say a Kenko teleconverter (or at least some models) will not report itself to the camera, so the camera will continue to autofocus. 1.) Image quality degradation by the TC, 2.) Loss of a full stop of light on a 1.4x TC, and 2 full stops on a 2x TC, 3.) Slower autofocus for sure, and. 4.)Options. 08-06-2023 06:36 AM. From Canon's product page for the RF 1.4X extender: Note: This extender is only compatible with the following RF lenses RF100-400mm F5.6-8 IS USM, RF100-500mm F4.5-7.1 L IS USM, RF400mm F2.8 L IS USM, RF600mm F4 L IS USM, RF600mm F11 IS STM, RF800 F5.6 L IS USM, RF800mm F11 IS STM, RF1200mm F8 L IS USM.