laserdisc capture: combining audio & video from 2 different players

[leslie80]

Hoping someone with experience can offer advice on capturing video from one machine, playing the same disc in another unit and ripping the audio (optical), then combining the two.

How difficult is is to sync? I especially wonder about how much timing difference there can be when different units are used. And I don't want to use software to "stretch" one to fit the other unless any resulting distortion is very very slight.

If there normally is a significant difference in playback speeds, how much improvement can be gained from a tech's callibration of the machines? I guess what I'm asking here is, how accurate is the callibration process - can I ever hope to have the times match (after I trim the start/end and "shift" them together)?

Reason I'm doing this in first place is because I'd really like to have lossless pcm audio to work with, but the better video performance comes from a machine that has no optical/coaxial out. I have little experience with captures/dvd authoring (all vhs souces) but I'm willing to go the extra mile on this project unless it sounds really troublesome.

thanks in advance for any feedback or suggestions!

[Nelson37]

I've used this method to synch audio and video from two different capture devices, should work similar.

First check that the original audio is in synch. Then load it into any editor that gives you a visual wave display. Load the second file, and synch the two displays. Add silence or cut the beginning as needed.

If a minor stretch of a second or two is needed, this will not be at all noticeable.

Make sure and check the beginning, a few minutes in, the halfway mark, a few minutes short of the end, and the very end, to see if synch is maintained.

Do NOT repeat NOT depend on software playback of elementary files to reliably determine correct synch. AUTHOR the files and playback the DVD image, THAT is a reliable and dependable method. Unless you have extra hair you don't really need.

[leslie80]

...load it into any editor that gives you a visual wave display. Load the second file, and synch the two displays. Add silence or cut the beginning as needed.

If a minor stretch of a second or two is needed, this will not be at all noticeable.
Do NOT repeat NOT depend on software playback of elementary files to reliably determine correct synch. AUTHOR the files and playback the DVD image, THAT is a reliable and dependable method. Unless you have extra hair you don't really need.

thanks for your response...those points especially sound helpful. Anyone with LD-specific experience want to respond to questions in my original post about timing? I have about 10 discs to convert, btw.

[chowmein]

I wouild recommend Reaper for syncing audio, it has very good built-in algorithms for stretching audio and maintaining high quality. Just position your cursor over the end of the audio file & CTRL-ALT to stretch to match your other track.