Canon has released a new firmware update for a selected range of Canon interchangeable EF lenses released between August 2011 and May 2012.
The firmware update (version 1.1.1) will ‘incorporate new functions’ into the EF 300mm f2.8 II USM; EF 400mm F2.8L IS II USM; EF 500mm f4L IS II USM and EF 600mm f4L IS II USM with specific serial numbers outlined on the Canon website.
The changes will adjust the control algorithm of the focus drive, enhance the drives responsiveness for more precise focus adjustments, and ‘in particular the new firmware enhances the AI servo AF capability of the lenses to track objects that move irregularly’.
Canon says that all those whose lenses fall within the serial numbers of affected products can take the glass into a Canon service centre and the firmware update will be provided free of charge.
Serial numbers affected:
EF300mm f/2.8L IS II USM – 790xxxxxxx through 913xxxxxxx
EF400mm f/2.8L IS II USM – 790xxxxxxx through 913xxxxxxx
EF500mm f/4L IS II USM – 880xxxxxxx through 910xxxxxxx
EF600mm f/4L IS II USM – 880xxxxxxx through 910xxxxxxx
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