1. Increases the manual focus speed when the manual focus speed switch is set to 1 or 2.
*The speed when the switch is set to 3 (slowest speed) will be unchanged.
2. Improves the image stabilisation effect during handheld shooting with a slow shutter speed when used with EOS 5D Mark IV, EOS 6D, or EOS R.
*In addition, this firmware enables a full-time manual focus function during AI Servo AF when used with the EOS-1D X Mark II. The lens must be sent to the Factory Service Center in order for this function to be enabled.
If the lens' firmware is already Version 1.1.2, it is not necessary to update the firmware.
You can download the firmware update from the Canon website – select the tab for Telephoto Fixed Focal Length and select the relevant lens from the list.
Before starting the firmware update procedure, please be sure to carefully read through and make sure you understand these instructions.