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Comment by dr_zoidberg | Hacker News Reader

I'm a bit confused here. There are a few Sony cameras (the RX series) that have a 960fps capabiilty, with exposure times of under 1/1000th of a second. That's around 8 times the 125 fps limit set by ITAR, yet those cameras are sold pretty much everywhere around the world. What am I missing/not understanding here?

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1 μs is less than 1000 μs. (And, yes, also they are probably not made in the US.)

The 1 μs is the time the electronic shutter takes to act, and there's no spec sheet for that that I'm aware of in the Sony cameras. As for exposure times at high frame rate, they go up to (down to?) 1/10,000th of a second, so definitely the electronic shutter must be working faster than 100 μs to reach that.

But as someone already pointed out, my main issue was understand the "International" (the I from ITAR) as meaning that it was a treaty signed by many countries, when it actually means "exporting from the US to International markets".

The language in the law is "electronic shutter speed (gating capability)", which I think is the same as the "exposure time." I mean, "exposure" is sort of a misnomer for digital video cameras: the focal plane is exposed to light all the time because there's no shutter. It's just that some of the time it's turned off ("gated"). And when you set the "shutter speed" on a mechanical camera to 1/60, that's the exposure time. You seem to be talking about something slightly different, like maybe the sensitivity rise time?

Japan doesn't have the same export laws as the US.

Right, that was it. I just took the "International" part of the name to mean as if it were signed by many countries, not a "from the US to the rest of the world".

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