Cheap solution for shooting with multiple (>2) cameras in sync (genlock or LANC?)

Question

I'm doing research into natural phenomena in computer vision, and I'm looking for a method of shooting video from multiple camera angles. It's likely that the subject will move very erratically, therefore any synchronization issues between the cameras will be a problem. Imagine a flame or flowing water, it's hard to say exactly but it's going to need to be microseconds rather than milliseconds. I will want to use as many as 8 cameras, ideally constrained by budget rather than the ability to keep them in sync.

The cameras the department owns are Canon DSLRs, however after much searching it seems infeasible to synchronize them, especially with this level of accuracy. Therefore if I can find affordable cameras that can be synchronized easily, we might be able to buy some.

The two options available to me seem to be genlock and LANC. From what I can tell, I'm not going to get hold of a single genlock-able camera for under, say, £5000. Even forgetting the genlock signal, that's too much for us to be able to afford one, let alone 8. The Sony/Canon LANC thing seems more feasible, however I can't find any reliable information about how to go about setting this up or what cameras actually support it which are available now. I keep hitting dead-ends trying to look into this, and it doesn't help that mostly everyone doing this is trying to shoot in just stereo. Can anyone advise me on what set up we'd need and how much it would roughly cost? Or if there's some other synchronization solution that someone would like to recommend? Ease and cost are the biggest factors! Quality of video would of course be nice, but something is better than nothing.

Thanks! And I hope this doesn't sound like a shopping recommendation question. While I do want to go shopping, I really just need help understanding the synchronization techniques, and I'll work out what to buy after that!

Answer 1

I've done 4-camera DSLR shoots with Nikon gear (D7000 & D3S). For our shots, we simply did a clapstick after all the cameras rolled AND just before cutting, so we had two sync points. Our longest shot was about 18 minutes long, and there was no noticable drift in sync in out post system. Although genlock is the PREFERRED way to go, I've found that a lot of digital equipment is ~close enough~ (heck, I've shot a music video with playback from a CD boombox and a constant speed (not crystal controlled) camera motor and it was SPOT ON.

For something that's under a minute, which your project sounds like, I'm fairly confident you won't need to worry about sync.

Just get a clapboard, make sure all the cameras can see it clearly and are RUNNING, then clap it down. Without cutting, jsut reposition your focus and focal length to where you need it for the shot. Capture the shot, then, again without cutting, zoom back out to where all eight cameras can see the clapstick, and clap. THEN you can cut your cameras. Sync up the frames where the clapstick hits in all 8 shots, e viola.

Good luck!