Canon 1D Mark IV firmware 1.0.6 upgrade and download

New version (Version 1.0.6) made the following improvements. AF tracking performance. automatic tracking AF tuning * AF is mainly directed against the back objects and slow near the object tracking AF optimized firmware 1.0.6 version 1.0.4 version for firmware upgrades, if the machine is 1.0.6 version, there is no need to upgrade. (Note that the firmware is 1.0.5