Canon 5D mkII firmware hack

Well, it seems if Canon are going to continue to keep their mouths shut regarding the future of any full manual control in video mode for the Canon 5D mark II, the internet will not.

Cinema5D user Hudson states:

“As an early goal, I have disabled the AGC for on the AK4646 audio chip that the 5D uses by overriding the sound_dev_task() at 0xFF856E60 to call audio_set_alc_off() at 0xFF856B14. The level is much too hot due to the wrong levels selected (it defaults to max gain?) but there is no shift in quiet scenes anymore. This is an easy first step that provides a proof-of-concept modification for the 1.0.7 firmware.

I can also log the audio levels as they are being sampled, which will make it possible to do on-screen level meters at some point in the future. My next step is figuring out how to add menus for the AGC disabling, then tackling the MVR_start_record() and LVAE_* functions.

Canon, we are tired of waiting for you to act. So, without you, we will first fix the obvious problems, then we’ll make it better. We’ll probably help you sell more cameras, too.”

Hudson makes a great point. As I have stated before, Canon is doing themselves NO favors by being ‘hush-hush’ on this topic. We are seeing a massive increase in professional use for this camera and I continue to see many niche’s for pro photographers to use this is the field. It just needs more control.

It’s great that users like Hudson are making such great progress, and I hope to see more very soon. It’s all very exciting!