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Camera freezes time at 10 trillion frames per second

inrs.ca

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Re: Camera freezes time at 10 trillion frames per second

#41

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…

That is not the case, from the article that you criticized:

> The first time it was used, the ultrafast camera broke new ground by capturing the temporal focusing of a single femtosecond laser pulse in real time (Fig. 2). This process was recorded in 25 frames taken at an interval of 400 femtoseconds and detailed the light pulse's shape, intensity, and angle of inclination.

Obviously they're only recording extremely small timeframes with this setup, but it is indeed real time.

Re: Camera freezes time at 10 trillion frames per second

#42

How close is this to planck time?

in orders of magnitude: about 10^13 * 10^-44 = 10^-31 ... not very close. If you amplify planck time to 1 s, a frame of this cam would take about 10^14 times the age of the universe (10^17 s) in comparison.

Re: Camera freezes time at 10 trillion frames per second

#43

Earlier quoted context omitted.

How is that relevant?

Just trying to understand.

Sorry, I thought you were challenging the notion that it's 10 trillion frames per second because it's not a full second (someone else did that elsethread)

Apologies for my tone

Re: Camera freezes time at 10 trillion frames per second

#44
post #33

This phys.org "article" is simply a copy of the INRS press release you can find here: http://www.inrs.ca/english/actualites/worlds-fastest-camera-... Actual paper: https://www.nature.com/articles/s41377-018-0044-7 Website for the INRS lab's project on this: http://coilab.caltech.edu/research_6.html (includes PDF of the above paper and others) As almost always, the phys.org "article" adds nothing of value to the press…

Thanks! We've updated the link from https://m.phys.org/news/2018-10-world-fastest-camera-trillio....

Re: Camera freezes time at 10 trillion frames per second

#45

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 with a balance of different motives and goals. Strict accuracy isn't always on the top of that list.

Re: Camera freezes time at 10 trillion frames per second

#46
post #33

This phys.org "article" is simply a copy of the INRS press release you can find here: http://www.inrs.ca/english/actualites/worlds-fastest-camera-... Actual paper: https://www.nature.com/articles/s41377-018-0044-7 Website for the INRS lab's project on this: http://coilab.caltech.edu/research_6.html (includes PDF of the above paper and others) As almost always, the phys.org "article" adds nothing of value to the press…

Thanks for the links! I see your point, but lots of people wouldn’t know about this if it was just a press release. I know I don’t have enough time to check for them.

Yes, of course. The person posting the link, however, should do even the tiniest bit of legwork.

Re: Camera freezes time at 10 trillion frames per second

#49

Earlier quoted context omitted.

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…

When the light reaches the camera, it has already moved roughly the same amount forward through the bottle. So my guess is yes, each frame is visibly showing "the past".

My guess is also that, if the laser is really focused, and if the bottle wasn't in the way, refracting some light back to the camera, we wouldn't even be able to see anything.

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