ext audio rec device, how to sync with 5dm2 video in PP?

[datadump]

firstly, i dont know much about video. so dont laugh.


i was reading this:

http://blog.vincentlaforet.com/2008/12/08/tips-and-tricks-for-the-5d-mkii-part-ii-audio/

first paragraph, he recommends just using external audio rec device instead of from the 5d mic input.

ok i dont understand this. so, you record audio separately with some device but then how do you sync the audio with the video thereafter? ie: lip synced with audio speech?

5d has some syncing capability with external audio device? how does this all work after you gathered everything and start editing in vegas?

[datadump]

i did some googling... and i found this:
http://www.singularsoftware.com/autosync/index.html
not traditional method but seems easy for "novice" folks

[Terjay]

What the hell...

Step 1: Make sure that the camera and sound are rolling.
Step 2: Have a dude go in front of the camera and clap once (and maybe say the scene and take numbers)
Step 3: Wait for the dude to go out of frame and shoot the scene.
Step 4: Repeat until the megabudget action flick is done.
Step 5: Sync the audio with the video with the help of the clap in your editing suite.
Step 6: Bask in glory!

[Trey T]

match it w/ your 5d sound. just listen and drag the ext. recorded sound to match. that's assuming your 5D footage is at 30.0000fps

if you covert your .mov to 29.97, you need to change some setting in vegas for that particular sound. because your video length is shorten by .1%, you need to change your sound length.

7d has the fix. it has the proper frame rate of 29.97.

[maxsideburn]

just keep in mind that if you're using a digital audio recorder that it's clock speed will be different than your cameras and that after a while your sync will drift. it won't be much, maybe a second over 20-30 minutes.

there is a way to calculate the clock speed of both devices and adjust your audio to never lose synch, but it requires lots of math and is not very easy. I can probably find the link for you if you need though.