I also like this 10,000 fps video [0] credited to Tim Samaras.
Start of Lightning Bolt Caught on Camera
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Re: Start of Lightning Bolt Caught on Camera
#2211k fps. Wow. I will never get tired of watching this stuff. That got me thinking, is there any theoretical limit to the number of frames that can be captured in one second?
Here is a pretty good video at a trillion frames per second: https://www.ted.com/talks/ramesh_raskar_a_camera_that_takes_...
Re: Start of Lightning Bolt Caught on Camera
#23Earlier quoted context omitted.
Electricity travels at about one third the speed of light. That would make a hard limit. Both shutter and data transfer speed.
But that would just be for one recording device. If you could use multiple devices, perhaps with small POV differences that could be corrected, I would expect no limit in that "lossy" case.
POV differences could be eliminated by a simple lens & mirror setup.
Re: Start of Lightning Bolt Caught on Camera
#24Earlier quoted context omitted.
But that would just be for one recording device. If you could use multiple devices, perhaps with small POV differences that could be corrected, I would expect no limit in that "lossy" case.
But if you surrounded an event with a sphere of sensors, there is still an upper limit. The number of sensors is a function of sphere radius, and whether they are limited to the surface of the sphere (which is reasonable since tightly packed sensors will, in general, get in the way of other sensors). A sphere 1km across has a surface are of 4 pi 1km^2 which is roughly 10^7m^2. If you had 1cm^2 sensors then you get 10…
It is not clear how one would synchronize the cameras on such fine time scales either.
Re: Start of Lightning Bolt Caught on Camera
#25Great video, the nature article is much more informative than the one linked. From the nature article, it seems this was the first video of natural bidirectional lightning, not triggered by rockets or aircraft: "In contrast to studies of rocket-triggered lightning and lightning initiated by aircraft, which found delays of 3–6 ms between the onset of negative and positive leader branches, this natural event exhibited…
...carry ten times the charge and exceed a billion volts of potential.
Great Scott!
Re: Start of Lightning Bolt Caught on Camera
#2611k fps. Wow. I will never get tired of watching this stuff. That got me thinking, is there any theoretical limit to the number of frames that can be captured in one second?
Here is a pretty good video at a trillion frames per second: https://www.ted.com/talks/ramesh_raskar_a_camera_that_takes_...
The cameras doing a billion+ frames/sec do not really function the way traditional cameras do -- i.e. you could never use one to take a picture of lightning (which is a pity). They work by firing off billions of extremely short bursts of laser light, and capturing images at progressively longer offsets from the release of a pulse. That strobing light is an integral part of how those cameras work, so they can only be used in situations where you can control the illumination of the object.
(Which does not make that technology, mind you, any less cool. But it's different enough from traditional photography that I thought it was worth mentioning.)
Re: Start of Lightning Bolt Caught on Camera
#27a) overloaded site
b) very nice, but is this "Hacker" News? More like Discovery Channel. How is this interesting from a tech point of view? High FPS cameras. Got it. Got it long ago.
Re: Start of Lightning Bolt Caught on Camera
#2811k fps. Wow. I will never get tired of watching this stuff. That got me thinking, is there any theoretical limit to the number of frames that can be captured in one second?
The number of captured photons is a good hard limit. dalke's answer for ultrafast photography is kind of "cheating" in the sense that they record the same event periodically so they can gather enough light. That technique can't record single unique events that fast AFAIK.
Re: Start of Lightning Bolt Caught on Camera
#29I also like this 10,000 fps video [0] credited to Tim Samaras. [0] https://i.imgur.com/W1X1qFI.jpg
I was wondering how you could talk about a video and then link to a single image (I think jpg doesn't support animation). But it turns out all of
https://i.imgur.com/W1X1qFI.jpg
https://i.imgur.com/W1X1qFI.gif
https://i.imgur.com/W1X1qFI.png
link to the same GIF. :)
Re: Start of Lightning Bolt Caught on Camera
#3011k fps. Wow. I will never get tired of watching this stuff. That got me thinking, is there any theoretical limit to the number of frames that can be captured in one second?
Not that it isn't awesome how fast cameras are, just keep in mind, the clip is 25ms. So at 11,000 fps, that would be 275 images (11 frames per ms). Not sure if we actually have a camera that can take 11,000 images in 1 second. (I guess that depends on the resolution)
Yeah we do. The company I work for designs sensors that can pull that off.