The Canon EF 200-400mm f/4L IS USM Extender 1.4x is a professional super-telephoto zoom lens with a built-in 1.4x extender that instantly switches the focal range to 280-560mm. It is designed for professional sports, wildlife, and news photographers requiring versatile reach without changing lenses, featuring 4-stop IS and fluorite elements for exceptional optical quality. Firmware updates address compatibility and autofocus improvements with newer Canon bodies.
Product released: June 1, 2013
Latest firmware version
Version 1.1.0, released April 24, 2018
What's new in version 1.1.0
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 (for EF200-400mm f/4L IS USM Extender 1.4x: 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.