Canon EF to RF 0.71x Speed Booster

Canon EF-EOS R 0.71x speed booster, a Canon EF to Canon RF mount adapter with an integrated optical element that reduces the EF lens's projected image circle by 0.71x and gains 1 stop of light. Designed for Canon RF bodies in Super 35 sensor crop mode (or APS-C bodies); the speed booster effectively makes a full-frame EF lens behave more like its full-frame field of view on the cropped sensor while gaining a stop of exposure. Full electronic passthrough: AF, IS, aperture, EXIF. Use case: Canon R5C in Super 35 mode shooting with EF cinema or photo glass, the speed booster restores something close to the full-frame field of view and adds light. Worth knowing: not all EF lenses pair well with this booster, some show vignetting or corner softness with very wide lenses. We test before deploying on a critical shot.