Using Extenders (Sold Separately) with the EF 400mm f/4 DO IS II USM lens
Article ID: ART174586 | Date published: 05/31/2019 | Date last updated: 05/31/2019


Using Extenders (Sold Separately) with the EF 400mm f/4 DO IS II USM lens



Lens specifications when using extender EF1.4x III or EF2x III are as follows.
Focal length (mm) 560 800
Aperture f/5.6 - 45 f/8 - 64
Angle of View Diagonal 4° 25' 3° 5'
Vertical 2° 25' 1° 40'
Horizontal 3° 40' 2° 35'
Maximum magnification (X) 0.18 0.26
  • Attach the extender to the lens, and then attach the camera. To remove it, reverse the order. Errors may occur if you attach the extender to the camera first.
  • With Extender EF2x II/III attached to the lens, only manual focus is possible. However, with the EOS-1D X*, EOS-1Ds Mark III, EOS-1Ds Mark II, EOS-1Ds, EOS-1D Mark IV, EOS-1D Mark III, EOS-1D Mark II N, EOS-1D Mark II, EOS-!d, EOS 5D Mark III*, EOS-1V/HS, EOS-3 camera, autofocusing with the center focusing point is possible.
  • When shooting with EOS A2/A2E/5, use -0.5 step exposure compensation when using extender EF1.4x II, and use -1 step exposure when using extender EF2x II.
  • Extenders cannot be used more than one at a time.
  • Autofocusing is still enabled with extender EF1.4x II/III attached.
  • When an extender is attached, the AF speed will become slower to retain proper control.

* AF can be used by updating your camera's firmware. Please check the Canon website for information about firmware updates.