Description

Canon EF Extenders increase the focal length of compatible telephoto lenses while maintaining full AF and metering capabilities. The 1.4x III provides a 1.4x magnification with minimal image quality loss, while the 2x III doubles the focal length. Both feature improved optical designs with fluorine coatings for enhanced performance.

Accessory	What it does
Canon Extender EF 1.4x III	Adds 40% more reach with about 1 stop of light loss. Example: 300mm f/2.8 → 420mm f/4; 400mm f/2.8 → 560mm f/4. Preserves AF, EXIF, and Image Stabilizer; a slight hit to AF speed and sharpness—stopping down ~1 stop helps. Best on L-series telephoto primes and supported zooms (e.g., 70–200 L, 100–400 L II) for wildlife, sports, and airshows.
Canon Extender EF 2x III	Doubles focal length with about 2 stops of light loss. Example: 300mm f/2.8 → 600mm f/5.6; 400mm f/2.8 → 800mm f/5.6. Stronger magnification but more impact on AF speed and image sharpness—use good light and solid technique/support. Best paired with top-tier L-series tele primes (300/2.8, 400/2.8, 500/4, 600/4) for distant wildlife and field sports.

Notes: EF Extenders mount between the EF lens and camera body. On EOS R cameras, use them with the EF-EOS R adapter
(camera → adapter → extender → lens). Compatibility is limited to specific EF telephoto L lenses;
not for EF-S lenses or most wide/standard primes and zooms. Autofocus performance varies by body and light level.