This is amazing. These framerates are 1/10th of what a cursory google search says I can get out of a top of the line high-speed camera, but for probably 1/100th the price. You could make so many awesome instructional videos with a tool like this.
1. Start recording with time delay. Probably requires
excellent clock synchronisation, a real time kernel,
reliable/comparable hardware (gatter timings differ at
small timescales). If this works, this would provide a
high quality equidistand framerate.
or
2. Start recording randomly, synchronize by time or
with an video event, and merge the frames. This will
result in a stochastic distribution of frame rates. The
usefulness of such a movie depends on what it is
supposed to be used for (thinking of scientific usage).
Will probably not give nice slow-mo movies. But
here comes the catch: With interpolation, the shortest
reachable frame rate dictates the quality of this
"superposition camera". How many cheap cameras do we
need to archieve, on average, the top line high speed
camera?
As long as your leads didn't have too much capacitance, it ought to just work.
The phase shifting you can do in software by (for example) restarting the camera hundreds of times till by chance it starts a frame with the phase offset you want, and then just run on from there.
I'm talking the actual quartz crystal here, not the output of some digital clocking chip (which you're right, wouldn't work).
"A Phantom camera he uses goes up to a maximum of 1000 fps in 4K — an exposure time of 1/2000 sec with a 180° shutter speed — and the image starts looking pretty dark on the screen."
I'm just trying to find what shutter speed you can get with the Pi camera.
Edit: Just having a little play:
./raspiraw -eus 500 -md 7 -t 1000 -ts tstamps.csv -hd0 hd0.32k -h 64 --vinc 1F --fps 660 -r "380A,0040;3802,78;3806,0603" -sr 1 -o /dev/shm/out.%04d.raw 2>/dev/null
500 microsecond exposure (1/2000 seconds) seems to run.
You can reduce the shutter time nearly arbitrarily, as long as you increase light intensity. I did place fast rotating propeller just above a 5000lm led, and did two 9us long flashes. See this image on how bright the two blades of propeller look, at both captured locations (the rest is dark, image was taken inside a closed cardbox, without flash everything was just black): https://raw.githubusercontent.com/Hermann-SW/Raspberry_v1_ca...
There was a MIT student project group that took 16 v1 cameras(!) global external shutter frames and created an animated .gif from that! "Ultra high-speed imaging, capturing matrix style bullet time" https://www.raspberrypi.org/forums/viewtopic.php?f=43&t=2404...
Reproducing something like this using cheap sensors would require some hardware acumen, but isn't unfeasible. Most industrial cameras, even cheap ones, have external triggers/clocks with nanosecond latency.
And unlike v2 camera, the cheap v1 camera allows (besides high framerate capturing) for global external shutter capturing as well(!). I did capture an in flight 109m/s airgun pellet 10 times in a single multiple exposure frame! https://stamm-wilbrandt.de/en/Raspberry_camera.html#global_e...