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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

#51

Post by fjsolwmv »

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.

"20 mph" (slower than the fastest 100m sprint, but faster than the fastest half marathon) would be more clear of an example.

Re: Camera freezes time at 10 trillion frames per second

#52

Post by fjsolwmv »

loteck wrote: post #45
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 feel like many readers of news carry this misunderstanding, so just to clarify: journalists very often do not get to write their own headlines. Many times they aren't even consulted on the headline. They may be just as surprised and dismayed as a reader/critic. It is frequently editors who write the headline, and it might even be editors who weren't involved in the reporting. Editors are always writing headlines wi…

In this case, the ambiguous statement is repeated 3 times in the article.

Re: Camera freezes time at 10 trillion frames per second

#56

Post by TaylorAlexander »

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...

I believe the approach in your video relies on a single laser pulse per frame, with many laser pulses combined to create the series of images for the video. The new approach, in contrast, emphasizes that the capture is done using a single laser pulse captured sequentially in real time.

Re: Camera freezes time at 10 trillion frames per second

#57

Post by max68 »

izzydata wrote: post #53

How many frames per second would you need to film at for a photon of light to be in an identical position on 2 frames?

Δd = 1cm = 0.01m v = 3e8 m/s

v*Δd = 3e6 frames/s

For the camera to pick up 1cm of difference between frames, you have to capture 3x10^6 frames per second. You can do the limit for how much you want your delta to be just by multiplying by the speed of light.

Re: Camera freezes time at 10 trillion frames per second

#58

Post by emeraldd »

izzydata wrote: post #53

How many frames per second would you need to film at for a photon of light to be in an identical position on 2 frames?

For 635nm red laser light, you'd need to be sampling somewhere in the order of 9.4 x 10^14 times a second to get two samples per cycle. Based on roughly 300000000m /635nm x2 but then the question comes down to how many cycles make up a photon and does that question even. Make sense in the first place.

Re: Camera freezes time at 10 trillion frames per second

#59

Post by cimmanom »

izzydata wrote: post #53

How many frames per second would you need to film at for a photon of light to be in an identical position on 2 frames?

A photon needs to actually hit the sensor in order to be recorded, so if we're considering the photon to be a particle (rather than a wave) it would have to be in the same position in order to be in two frames at all.

Re: Camera freezes time at 10 trillion frames per second

#60

Post by rapnie »

jwalton wrote: post #54
izzydata wrote: post #53

How many frames per second would you need to film at for a photon of light to be in an identical position on 2 frames?

Light travels roughly 300 billion m/s, so at 10 trillion fps, light moves about 3cm.

Joking? Wikipedia: 299,792,458 metres per second
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