18th December 2011, 9:47 AM
(This post was last modified: 8th January 2012, 12:40 PM by Dark Jaguar.)
It didn't actually record an entire second of video. The recording only lasted the time of a single laser pulse (the light source). While it is "a trillion FPS" it wasn't on long enough to record a trillion frames. That's just the ratio.
As for how it worked, yes, there is no shutter, film reel, or electronic sensor nearly quick enough to capture those speeds. The "hundreds of cameras collated together" is close, but here's the trick.
Essentially, the camera they used recorded one LINE of pixels, using a special "reverse CRT" to move through from the left to the right side of the image in that sort of insane time. There was a whole row of image recorders that the "reverse CRT" was hitting in the camera, and even then it was so packed it could only get a single row of pixels. So, because they knew the exact timing of the laser pulse and the camera array, they could reproduce identical conditions repeatedly. There was a moving mirror that could adjust the "height" of the recording. So, this mirror was moved slightly, the laser was fired and several shots were taken over and over again for each row in height. These were all combined into a single video in the end, and there you have it. It's entirely real, but collated from repeated shots with identical lighting conditions. In that way, it could be seen as a cheat.
The speeds are still crazy though. At that speed a bullet would stand still.
As for how it worked, yes, there is no shutter, film reel, or electronic sensor nearly quick enough to capture those speeds. The "hundreds of cameras collated together" is close, but here's the trick.
Essentially, the camera they used recorded one LINE of pixels, using a special "reverse CRT" to move through from the left to the right side of the image in that sort of insane time. There was a whole row of image recorders that the "reverse CRT" was hitting in the camera, and even then it was so packed it could only get a single row of pixels. So, because they knew the exact timing of the laser pulse and the camera array, they could reproduce identical conditions repeatedly. There was a moving mirror that could adjust the "height" of the recording. So, this mirror was moved slightly, the laser was fired and several shots were taken over and over again for each row in height. These were all combined into a single video in the end, and there you have it. It's entirely real, but collated from repeated shots with identical lighting conditions. In that way, it could be seen as a cheat.
The speeds are still crazy though. At that speed a bullet would stand still.
"On two occasions, I have been asked [by members of Parliament], 'Pray, Mr. Babbage, if you put into the machine wrong figures, will the right answers come out?' I am not able to rightly apprehend the kind of confusion of ideas that could provoke such a question." ~ Charles Babbage (1791-1871)