EF 200-400mm f/4L IS USM Extender 1.4x Firmware Version 1.1.0

8th May 2018
Changes in firmware
Firmware Version 1.1.0 is incorporated with the following correction.

1.Corrects a phenomenon in which the subject may not be in focus on some occasions when using this lens with some camera models (*) and performing AF shooting from approximately 3m.

* Some camera models:
EOS-1D X Mark II, EOS-1D X, EOS-1D C, EOS 5Ds, EOS 5Ds R, EOS 5D Mark IV, EOS 5D Mark III

Firmware Version 1.1.0 is for lenses with Firmware Version 1.0.0. If the lens’ firmware is already Version 1.1.0, it is not necessary to update the firmware. 

Preparations for the Firmware Update:
In the folder you downloaded are the firmware (file name: EF015110.lfu / file size: 360,500 bytes), and instructions on the firmware update procedures (a PDF file in five languages: Japanese, English, French, Spanish, and Simplified Chinese). 

Before starting the firmware update operations, please be sure to carefully confirm your understanding of these instructions.
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