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.

Rate this Article
Was this article helpful?
Yes, This document is helpful
No, This document needs a clearer explanation
Please provide your comments