[Park Seward]

You can do it the "easy" way or the "right" way.

The easy way is to do a clap stick or hand clap visible on camera and heard on the sound track. You then manually sync the tracks together. Be sure to ID the tracks visually and aurally. (take 21, etc). You must slate the cameras each time they start a take.

It can get real confusing if you use take 5 of the bass, take 27 of the guitar, take 19 of the keys, etc. Notes will be very important.

The right way is to provide SMPTE timecode from the Pro Tools system to send to each camera. Also, you need a black burst generator to lock the PT and cameras so they don't drift. Timecode is not enough in itself since the timecode phase will drift. As you may know, timecode changes at the start of a frame. With no reference, the timecode will drift.

This is assuming that the cameras can take black burst and external SMPTE timecode. Some prosumer cameras cannot. If not, see "easy" above.

Someone need to make a note as to which take is used in the final recording. If you take 50 takes of the guitar solo, which one was used in the final song? Or to make matters worse, which parts of the 50 takes were used. Of corse you can use cutaways to hide any obvious sync issues.

If you are recording everyone at the same time, it gets easier. You will have some drift if you don't have a black reference to everyone but a short song may hold together fine. Just remember you may need to nudge video a little.

Good luck.