News archive

Tuesday, 4 December 2012

EOS-1D X and the f8 issue

Auto-focusing may not function at f8 on some EOS-1D X cameras with firmware version 1.1.1. This version enabled the centre AF point to autofocus when the camera is used with lens/extender combinations, whose combined maximum aperture is f8.

On some of the cameras with firmware version 1.1.1, auto-focusing does not function at f8. This is not an issue with the firmware itself, but with its installation at the factory. The problem can be overcome by overwriting the firmware. This phenomenon does not occur with a camera whose firmware has been updated by a user, or by a Canon service center.

Cameras with 4 or 5 as the sixth digit from the left in the serial number are affected.


Even when the sixth digit from the left in theserial number is 4 or 5, cameras with a white dot in the battery compartment are not affected.

To overwrite the installed firmware and activate the auto-focusing at f8, simply re-install firmware version 1.1.1. There is no change to the firmware version, as this is not an issue with the firmware itself.
You can download the firmware from the Canon Download centre at:

Here to help 01869 331741