Canon HFS100 + recording audio seperately

[intellijel]

I am trying to record video of a synthesizer so I set up the camera to record at it's native 60i and then fed the audio from the synth to my computer (using ableton live to record it).

The plan was to sync the video and audio together in an editor (sony vegas) afterwards.

The problem is that once I did this I found that the audio on the camera (recorded by built in mic) was higher pitched and playing back faster than the audio I rendered from Ableton live.

I tried re-rendering the audio from Ableton at 48Khz but did not notice a difference...


I think I may be getting lost with some things here:
1. Should all my audio in Ableton be recording at 48Khz (from the beginning, not just rendered this way?)
2. Do I need to do anything to the video I import to Vegas? (i.e. conversion? format correction?)
3. Should I be shooting at 60i or 30i?

Any tips to achieve this simple goal would be great!

[edDV]

1. yes
2. no
3. 60i and 30i are the same thing.

Since consumer cameras and computers can't be genlocked to an external reference, there will be a small clock drift error in the camera and a wide drift in the PC clock. Pros sync video and audio capture to an external reference so everything matches in post. They use a slate with time code so editors can quickly sync separate sound.

Manual technique is to record the sound to the camcorder and PC and then compare waveforms during the edit. You will find variable and continuous time base drift that requires audio speed changes to match the video. It is challenging to maintain lip sync. Perfect lip sync requires sub frame audio adjustment.

A worse case is shooting multi-camera with separate sound. You will find ungenlocked cameras drift relative to each other. Normally you choose one camera as reference and then adjust other cameras and sound tracks to the reference camera track.

An alternate "music video" technique is to match video to a base audio track. This implies a multi camera quick cut technique with precise video to sound sync match where lip sync is visible.