Clips are slightly out of sync

Thanks for the description ... I would not have thought of that from your earlier comments.

So it sounds like you take say the three different guitar video tracks, three synced audio tracks (one for each different guitar part) ... and try and sync the audio with video while you're cutting between camera views while the audio program plays.

Shooting a higher frame rate, and using that for the sequence frame rate ... say 59.94/60fps might make the sync close enough to be less noticeable to you. Although if you dropped that back to 24/23.976/29.97 for output, not sure how that would all look ... hmm.

Neil

Richard has a great comment!

Besides this video/video-post thing, I'm also a musician and have performed in, directed, and recorded various music things. Including directing a hand-bell choir performing in a loft at the back of the sanctury while the organist and the main pipe installation were at the front, 200 feet away.

Timing when 'we' played against the organ was tricky enough, as if we played what sounded "with" the organ, our sound got to the audience in-between as as notably late. So it took some practice on my part to keep my group directed ... and ahead of the organ.

Then the organist decided to change "stops", the selection of pipes, for one section. To the "antiphonal organ" stop of pipes that were also in the balcony with us. Oh, that was a joy ...

Of course, we needed to play exactly with those pipes, but before and after, when he was using the main organ, play ahead of him. Right ...

We hadn't been doing too bad before he added the antiphonal organ. After that, we never 'stuck the landing' for getting accurately "with" the organ. And got some comments that it was awesome, others that well it was nice but can't the bells keep up with the organ?

I did a video recording, and from that, told people I could prove the organ wasn't keeping up with the bells! Because naturally, with the bells right next to the camera, our sound arrived first most of the time.

So ... as both someone with years in camera work and now video post, and as a life-long musician ... recording music live is a hassle. And there are always compromises.

Neil

In the natural world sound is allways behind the picture, due to the fact that the speed of light is a lot faster than the speed of sound. The human brain expects this and it looks natural. If you have close sync in a video and it still looks 'wrong' there's a good chance the sound is before the pictures, the brain cannot cpoe with this. Try moving your 'wrong' pictures a frame earlier it might all heal up.

As an asside, what is real sync?

I have made a dozen or so dvds of organ recitals, shot around the organ consoles. When the organist presses a key you expect to hear the note but with some stops there is a delay before the pipe speaks so the sound is late. The pipes themselves are often tens of feet away and some are closer than others. So just listening live at the console the sound is 2 or 3 frames late. The  recordist I work with mics the organ about 80 feet down the nave so that is 2 frames late. When we made the first dvd we tried various sync variations and the only one that looked right was to have the note heard as the key was pressed, this, in real life, never occurs. 

In St Paul's cathedral in London there is a rank of trumpet pipes over the west door,  a couple of hundred feet from the rest of the organ. If using these pipes with the main organ the organist has to play the pipes a beat early so that their sound is in sync with the other stops. Of course if you are sitting at the west end everything is even furthur out of sync.

unless you're shooting in a professional environment where all the cameras are "genlocked" there's gonna be some drift between the cameras.  If you had a very precise clock, you'd see that video which is shot in 1 frame increments and those frames would not be perfectly aligned between the cameras.  The fact is that you may hear the difference between the different audio tracks, but it's highly unlikely you'll be able to perceive any problem with the synch within a frame.  and regardless, you're just gonna have to live with it.

If you have separate audio, something that has no video ... simply selecting all the media both camera and the audio, Premeire will auto-select the audio-only file to sync to. It's normally a pretty easy process to setup.

Then it creates a multicam sequence and depending on how you select that to open it, it appears as either a stack of all the cams on different video tracks for selecting the 'cut' order (blue on the timeline), or a single track (in green) as-cut.

Neil

As you said video clips can only be moved in one frame jumps. There is no real way around this. Audio on the other hand cane be moved down to sample level, often 48000th of a second. If you unlink the audio from the video and select 'audio time units' instead of timecode you can then move the audio at this higher resolution. I often do this to align audience reaction audio to stage audio to remove time delay echos. With regards to video with modern rolling shutter cameras the top of the frame is not in sync with the bottom anyway.