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Camera freezes time at 10 trillion frames per second

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Re: Camera freezes time at 10 trillion frames per second

#11

Post by fiter »

degenerate wrote: post #3

It doesn't really capture 10 trillion frames per second. The laser pulses at a regular interval, and the combination of the regular pulsing + multiple pictures taken at different points along those pulses makes for 10 trillion distinct frames captured within the timeframe of 1 second. There is no actual video captured. I get that being a tech journalist is difficult, you have to juggle between the tech and the layman…

There's even an easy analogy for this! Putting strobe lights on fast, repetitively moving machines allows you to see their motion slowed down.

EDIT: I'm responding here to the parent poster's claim, not to the original article. For more information on the technique used in the article, see this other article[0] about "CUP" vs this article about "T-CUP". In CUP they use a random 2D sampling of a scene projected onto a streak camera.

[0] https://www.osa-opn.org/home/articles/volume_26/december_201...

Re: Camera freezes time at 10 trillion frames per second

#12

Post by ummonk »

degenerate wrote: post #3

It doesn't really capture 10 trillion frames per second. The laser pulses at a regular interval, and the combination of the regular pulsing + multiple pictures taken at different points along those pulses makes for 10 trillion distinct frames captured within the timeframe of 1 second. There is no actual video captured. I get that being a tech journalist is difficult, you have to juggle between the tech and the layman…

Note that a rate such as "x frames per second" doesn't mean it needs to be able to operate for the full second. That would be like saying you can sprint at "12 miles per hour" means you can run all of 12 miles in an hour.

Re: Camera freezes time at 10 trillion frames per second

#13

Post by ummonk »

fiter wrote: post #11
degenerate wrote: post #3

It doesn't really capture 10 trillion frames per second. The laser pulses at a regular interval, and the combination of the regular pulsing + multiple pictures taken at different points along those pulses makes for 10 trillion distinct frames captured within the timeframe of 1 second. There is no actual video captured. I get that being a tech journalist is difficult, you have to juggle between the tech and the layman…

There's even an easy analogy for this! Putting strobe lights on fast, repetitively moving machines allows you to see their motion slowed down. EDIT: I'm responding here to the parent poster's claim, not to the original article. For more information on the technique used in the article, see this other article[0] about "CUP" vs this article about "T-CUP". In CUP they use a random 2D sampling of a scene projected onto a…

That's not what they're doing. They're seeing the actual motion of something that doesn't necessarily move repetitively.

Re: Camera freezes time at 10 trillion frames per second

#14

Post by lerchmod »

ummonk wrote: post #12
degenerate wrote: post #3

It doesn't really capture 10 trillion frames per second. The laser pulses at a regular interval, and the combination of the regular pulsing + multiple pictures taken at different points along those pulses makes for 10 trillion distinct frames captured within the timeframe of 1 second. There is no actual video captured. I get that being a tech journalist is difficult, you have to juggle between the tech and the layman…

Note that a rate such as "x frames per second" doesn't mean it needs to be able to operate for the full second. That would be like saying you can sprint at "12 miles per hour" means you can run all of 12 miles in an hour.

Some people can...

Re: Camera freezes time at 10 trillion frames per second

#15

Post by SketchySeaBeast »

thanatos_dem wrote: post #4
ttty wrote: post #2

Where is the video? That's what I'm looking for

Here’s a video from 2011, but it’s only at 1 trillion FPS using the same laser pulse approach - https://m.youtube.com/watch?v=-fSqFWcb4rE Also, the music is pretty cringey, so I’d just leave it muted...

Watching this confuses me as to the timing of it all... if the conceit is that we're watching the bundle of photons move through the bottle that's because the photons from the source are hitting the camera, right? So is it the light moving through the bottle + the travel time to the sensor? Should refraction and reflection across the surface cause a lot of weird visual interference (as the bottle's size is no longer insignificant the time scale for lights velocity)? Is that what we're seeing there?

Re: Camera freezes time at 10 trillion frames per second

#16

Post by tantalor »

degenerate wrote: post #3

It doesn't really capture 10 trillion frames per second. The laser pulses at a regular interval, and the combination of the regular pulsing + multiple pictures taken at different points along those pulses makes for 10 trillion distinct frames captured within the timeframe of 1 second. There is no actual video captured. I get that being a tech journalist is difficult, you have to juggle between the tech and the layman…

"The first time it was used ... the process was recorded in 25 frames taken at an interval of 400 femtoseconds"

1 / (400 femtoseconds) = 2 500 000 000 000 hertz

So definitely in the "trillion fps" for a very short period of time with multiple frames.

Re: Camera freezes time at 10 trillion frames per second

#17

Post by zwieback »

degenerate wrote: post #3

It doesn't really capture 10 trillion frames per second. The laser pulses at a regular interval, and the combination of the regular pulsing + multiple pictures taken at different points along those pulses makes for 10 trillion distinct frames captured within the timeframe of 1 second. There is no actual video captured. I get that being a tech journalist is difficult, you have to juggle between the tech and the layman…

Agreed. We work with traditional high speed cameras (up to 1Mfps) and I thought, wow, someone is going several orders of magnitude faster??

Turns out the research is super cool and the paper is well written and interesting but it's not what I thought.

Re: Camera freezes time at 10 trillion frames per second

#18

Post by quadcore »

endorphone wrote: post #5
degenerate wrote: post #3

It doesn't really capture 10 trillion frames per second. The laser pulses at a regular interval, and the combination of the regular pulsing + multiple pictures taken at different points along those pulses makes for 10 trillion distinct frames captured within the timeframe of 1 second. There is no actual video captured. I get that being a tech journalist is difficult, you have to juggle between the tech and the layman…

I don't quite understand how your original point refutes the headline. They are saying that it captures frames at a rate that, measured in seconds, would be ten trillion frames per second. The headline seems entirely accurate.

How long can they maintain that frame rate for?

Re: Camera freezes time at 10 trillion frames per second

#20

Post by debt »

thanatos_dem wrote: post #4
ttty wrote: post #2

Where is the video? That's what I'm looking for

Here’s a video from 2011, but it’s only at 1 trillion FPS using the same laser pulse approach - https://m.youtube.com/watch?v=-fSqFWcb4rE Also, the music is pretty cringey, so I’d just leave it muted...

Only 1 trillion FPS? Yawn
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