Following the recent forum posting by a moderator in Canon’s official forums, Canon has issued a product advisory concerning the slow AF speed for the 5D Mark III and 1D X when using a Speedlite AF assist beam.
Firmware updates to address this issue are expected for the 5D Mark III and 1D X in April 2013 and May 2013, respectively.
The full product advisory from Canon is reproduced below. [Read more…]