Canon has released one of the most significant firmware updates for the camera thus far.
First announced in October 2012, version 1.2.1 of the SLR's firmware will allow users to output a clean HDMI feed. One of the key disadvantages up until now for the Mark III has been the extra information that is output alongside the Live View image when using HDMI out, which made the footage unusable for actual recording purposes.
The update allows users to record uncompressed (YCbCr 4:2:2, 8 bit) video to an external recorder or display it on an external monitor during filming. This puts the Mark III in line with several Nikon SLRs, which are able to output clean HDMI feeds, such as the D800 and D4.
Other updates include a tweak to the AF system, which enables the use of the centre point at f/8. Without the firmware update, this centre point is only available on the Mark III with maximum apertures up to f/5.6. The AF update will be of most use to sports and wildlife photographers who rely on accurate performance when using telephoto lenses and extenders. Canon claims that the new firmware will allow photographers to use the EF 600 f/4 lens and a 2x extender, getting an effective focal length of 1200mm with accurate AF performance.
The firmware is available for free download from Canon's website.