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Comment by ziml77 | Hacker News Reader

Nice, but aren't the cameras supposed to be triggered in sequence instead of all at once? I thought there was still a little bit of motion in the movies, but in these the subjects all freeze in place.

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You can do that with synchronized video cameras and AI inbetweening: https://www.youtube.com/watch?v=AsY0sKH3nG4&t=4s

That's true if you want them to move slowly like in the movie. But to just freeze them you need to take all the pictures at the same time

Technically yes but since the resulting bullet time sequence is really short, it won't make much of a difference, I think.

yes. in the special edition DVD, the special features show the bullet time scene in the studio and you can hear the shutters from the camera clacking like dry fire from an automatic rifle

One would think the cameras all record at the same time and you can just pan around and adjust speed whenever?

In theory the idea also enables a higher frame rate than that of which the cameras are individually capable, thus allowing a finer slow motion effect.

A nice compromise (since a wedding photo booth isn’t going to be super choreographed) could be to group the cameras in to, say, two groups. Trigger them periodically, 180 degrees out of phase with their neighbors, and assuming the virtual camera is moving by one real camera per frame, you’ve got double the frame rate but can still choose a path in post-processing. And of course it could easily be abstracted out to n camera sets.

This is getting pretty complicated though, he “hard-coded” the camera motion into the shape of the frame. Physical things are hard, haha.

Depends on the setup you're using the trouble with doing video is to get the effect to be smooth you need frames at very particular times from each location which is tough to ensure out of video equipment where a bank of cameras you can trigger to take a single frame in sequence. To do the same with video you need to have a system to send a slightly out of phase sync signal to each camera in the array or just wing it and fudge the jittery motion and ramping with some VFX in post production.

Now that you mention it: if they were all recording video you probably could adjust speed and pan around freely in post...

These particular cameras can't do video (same with the original Matrix bullet time setup).

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