Comments for 5D mkII pairing with 1.4x extender and 100-400 ii

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thank you!
by: nick

thank you very much for the information! that really helps my direction and understanding...always learning. much appreciated, have a great day!

Canon-USA Answer To Tele-extender Compatibility
by: Bruce

Dear Bruce,

Thank you for contacting Canon product support regarding your EOS 5D Mark II, the Extender EF 1.4x III, and the EF 100-400mm f/4.5-5.6L IS USM lens. I would be happy to help you with this.

I'm afraid this particular combination will not allow for autofocus operation. You will need to focus manually.

When using the EF Extender 1.4x III or 2.0x III on most of our EOS cameras, the camera will not be able to autofocus if the new maximum aperture after the extender is smaller (a higher number) than f/5.6. For instance, if you have a lens that has an aperture range of f/4.5-5.6 (such as the EF 100-400mm f/4.5-5.6L IS USM), adding the 1.4x extender changes the maximum aperture by 1 stop, resulting in an aperture range of f/6.3-8.0. Likewise, the 2.0x extender pushes the aperture range up by two stops, to f/9-11. Because of the reduced amount of light entering the camera and larger depth of field due to the reduced aperture, most of our camera's autofocusing systems cannot operate.

As a general rule, for proper AF operation with our extenders on most of our cameras, you will need a lens with a maximum aperture of f/4 or better with the 1.4x extender and f/2.8 or better for the 2.0x extender.

There are a couple of exceptions to this rule. Most of the EOS 1D series, the EOS 5D Mark III, and the EOS 7D Mark II retain autofocusing capabilities from f/5.6 to f/8, but are limited to the center point only. The EOS-1DX Mark II and the EOS 5D Mark IV can autofocus with all focusing points down to a maximum aperture of f/8.

I hope this information is helpful to you. Please let us know if we can be of any further assistance.

Thank you for choosing Canon.


Technical Support Representative"



You're welcome. Good Luck!

by: Anonymous

ah, looks like only the 5D mkIII has compatibility with the 2013 firmware update. thanks for the resource!

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