By site editor Dan Chung:
I’ve always wondered what the electronic connections on the Canon’s CN-E cinema lenses were for. Given that cinema lenses don’t have an electronic iris and no autofocus it would seem the contacts don’t have much purpose. Well I was wrong – with Canon’s latest 1.3.x firmware update the EOS-1D C will be able to use the contacts to get lens data from CN-E lenses, using it to relay aperture info to the camera display and also apply in-camera lens aberration correction to the image. The correction options can be turned on or off in the camera menu and are used to reduce chromatic aberration (colour fringing in high contrast areas of the image) and also make peripheral illumination more uniform.
Also in the new firmware is an option for the camera’s 3.5mm mini-jack audio input to receive line-level rather than a mic-level input. This means you can now hook it up to devices like a Zoom audio recorder without the need for special cable (normally needed to reduce output to mic-level).
The new firmware can only be uploaded at a Canon service centre and should be available from mid-October.