A laser pointer at 2B FPS [video]

As I understand it, this is sort of simulating what it would be like to capture this, by recreating the laser pulse and capturing different phases of it each time, then assembling them; so what is represented in the final composite is not a single pulse of the laser beam.

Would an upgraded version of this that was actually capable of capturing the progress of a single laser pulse through the smoke be a way of getting around the one-way speed of light limitation [0]? It seems like if you could measure the pulse's propagation in one direction, and the other (as measured by when it scatters of the smoke at various positions in both directions), this seems like it would get around it?

But it's been a while since I read an explanation for why we have the one-way limitation in the first place, so I could be forgetting something.

[0] https://en.wikipedia.org/wiki/One-way_speed_of_light

Ah, two billion. The first several times I saw this it looked like "twenty eight", which didn't seem terribly interesting.

The view from one end of a laser going between two mirrors (timestamp 1:37) is a fairly good demonstration of the camera having to wait for light to get to it.

I thought his method of multiplexing the single channel was very smart. I guess it's more common on 2 channel or high end 4 channel scopes to have a dedicated trigger input, which I've checked this one doesn't have. That said, there're digital inputs that could've been used. Presumably from whatever was controlling the laser.

Techniques like this are/were used to film nuclear explosions (but with a single explosion).