I've been recording quite a bit of video on location (link goes to YouTube movie sample) for Lowepro as part of my photo evangelist work. For the most part, things have gone well. That's only because I've been lucky. Today my luck ran out.
I'm plugging a lav mic directly into a Canon 5D Mark II and recording both audio and video at the same time. (Yes, I know I can record with separate devices, but I need to turn these projects around really fast.) The problem with 5D audio is that it employs Automatic Gain Control (AGC) that pumps up hiss, plus you have no visual or audio indication of what you're recording. This lack of feedback nailed me today when I didn't push the mic connector firmly and all the way into the audio jack on the 5D. Result: I recorded audio with the onboard mic instead of my external lav. It sounded like this:
Canon 5D Mark II Native Audio with Onboard Mic
When I got back to the room to process and upload the video, I was horrified. Kevin, one of my Lowepro comrades, had just told me about the Magic Lantern Firmware enhancement for the Canon 5D Mark II. It temporarily disables that nasty AGC, allows you to choose between internal or external mics, lets you set the audio levels manually, then provides visual meters so you can monitor your recording in real time. For added protection, enable the camera's A/V jack for audio monitoring with headphones. Needless to say, I was suddenly very interested.
I downloaded the firmware, copied it to a CF card with my card reader, and enabled it on the 5D Mk2 by going to Firmware on the menu and hitting OK. The enhancement is only temporary. Once you turn off the camera, it returns to its normal firmware. Very cool.
After installing, Kevin did an audio test for me with my lav mic and the Magic Lantern Firmware enabled. In the very same environment as the first recording, here's how the audio recorded:
Canon 5D Mark II Audio with Lav Mic and Magic Lantern Firmware
The Magic Lantern site does a great job of explaining all the ins and outs of this wonderful software. I encourage you to read everything, then watch the movie they have embedded on the site. It really explains what's going on. You can download for free, but you'll probably be inspired to hit the donation button after a few uses.
I'm going to reshoot the videos tomorrow that I botched today. With the Magic Lantern Firmware, I'm sure things will go much smoother.