In a building over there, is a camera that absolutely blows my mind.
Is this camera capable of filming the speed of light?
- Yeah. - Dan: Heck.
- Very high tech stuff, guys. - The maximum speed we can do
is 10 trillion frames per second.
This is the reason we came here. Crank it up all the way?
- Yeah. - All right.
I just feel like no human should ever have seen this.
We've filmed the fastest thing.
We've hit our ceiling.
It's not going to be anytime soon
that we're going to film anything faster, so...
Not this year, maybe.
Should we just invent some stuff that's faster?
Let's just start making up stuff.
Yeah, this camera is, like, 50 trillion--
You clearly haven't seen super light.
It was really interesting, the set-up.
You can tell that so many thousands of hours of research
had gone into creating that camera.
I mean, the footage, you can't really tell what's happening.
When you think about what's actually happening,
what you're actually seeing, it's more impressive than the actual footage.
Yeah, it's one of those things where the idea of it
is way more impressive than the visual of it.
'Cause the visual of it looks like
a slightly outdated film effect.
With a picture of a bottle on it.
( synth music playing )
I would say of all the videos we've shot,
this one, while we were shooting it,
I was struggling to comprehend
how the camera was actually acquiring those images.
And also then, you've got to think about the time scale involved.
Like, I can't get my head around how short a picosecond is.
- It's absolutely insane. - Well, nothing else happens on that sort of scale.
Well, as we're struggling to wrap our heads around it,
we thought it would be best to actually ask
one of the people who invented the technology.
We're here with Lihong, who's one of the inventors of the camera.
Do you think you could talk us through it, exactly how it works,
and we can try and understand it,
because I just don't get it right now.
Sure. For the first time, humans can see
how a light pulse propagates in space.
But before I talk about our camera,
let me talk about the standard streak camera.
A standard streak camera gives you a 1-D movie
that's really fast.
You only allow the X dimension,
or horizontal dimension, to pass through,
then you watch a horse race through a slit.
- It won't be as fun. - Right.
We're so used to your smartphone cameras
seeing at least the world in 2-D, if not 3-D.
Yeah, it's a world you can relate to.
Exactly. And so let me talk about how our camera works.
Let's say we start with this object.
But before we send it to a standard streak camera,
we're going to route it
to this digital micromirror device.
We write this code, and that's an important step,
because that allows us later on to decode everything
to generate a 2-D movie.
And this encoded object
is routed to this streak camera
Unlike the standard use of the streak camera,
we allow the wide dimension,
or the vertical dimension to come in.
At the back end, you can use a slower camera
to capture whatever you want to detect.
It's a great invention.
This technology allows us
to look at really short time intervals.
Why do we have to use a laser
instead of just a normal light bulb or a flashlight?
A flashlight turns on too slowly for us to observe.
A laser, we can make it really short.
So we use a state of the art laser pulse,
and that turns on within a femtosecond scale.
So, the laser pulse is on the femto scale?
Right, right. Yeah. But our camera works so fast...
- Yeah, I was going to say. - ...even nanoseconds feels like eternity.
This camera makes it look like the light's just hanging out forever,
but it's really still on the pico scale.
Lihong:
the slowest slow motion movies right now.
The hope is that our camera can be used to study some fundamental physics.
We've all heard of sonar, but there's an optical
counterpart of sonar called lidar.
Very much like radar, as well.
You basically detect a round trip time.
So, from the time, you can measure distance.
Could that be used to see around corners?
Yes, it is feasible, although we haven't done that physically.
- That's like a superpower. - Yeah.
For now, we're doing something very similar to that.
Let's say you have a foggy situation or a cloudy situation.
To your naked eye,
you would not see the airplane at all.
So we can just see through the cloud
and get a movie like this.
You can see this little airplane.
Gav:
the depth information this way, as well.
Lihong:
This would be actually much more accurate than our eye.
And this could be useful,
even maybe in the future for autonomous cars.
We want to drive in a cloudy situation--
a foggy situation,
and you can see objects through the fog.
- Another superpower. - Yeah.
We're also thinking about something more biological.
We know that our brain is the most complex machine probably in the universe.
I want to figure out how our brain computes one plus one, even.
By using our camera, we can potentially see that.
Would this be useful for detecting damage in the brain?
Like, if someone's had a stroke,
would you be able to see that on this?
That's certainly our hope.
Does that mean that in the future,
people will be able to read my mind?
That's one possibility.
I just feel like it must feel like such an accomplishment
to have seen the fastest thing.
It was a surreal moment when we got the first movie at light speed.
Because that's the ceiling as we know it.
We never thought it would be possible, yes.
Well, thank you very much, Lihong,
for teaching us all this fascinating stuff.
I'm going to be thinking about this on the way home.
I'm going to be watching this and trying to understand it.
- Several times. - All right, back to you, Gav and Dan.
Thanks, us.
This is our time cheat sheet,
just a list of all the different time scales.
We usually hang around milliseconds.
A lot of our exposures are down to the microsecond.
- Yeah. - Sometimes when we're using the 2511,
we'll have exposure times that are pushing on the hundredths of nanoseconds,
but that's about as far as our Phantoms go.
- Yeah. - We were down here with this camera
and around in this ballpark.
But before, right, I kind of had it all comprehended.
I had it all in my mind, like, "Yeah, this is the amount of time."
- Now I've lost it again. - Well, what--
- That many zeroes? - What blows my mind
is we had femtosecond long piece of light
- going all around... - Yeah, we did.
...filming it with picosecond differences between frames.
What on Earth is all this about?
Yoctosecond?
Surely, that would make the light look like you blinking.
At this point, I feel like you might
as well just say infinity.
We've actually had a lot of comments over the years of doing this
asking us to film light with our Phantom.
Like, film a torch or a laser beam
or a light bulb or something.
And I always have to explain to them,
light is so fast that our Phantom camera
sees light the exact same way as our eyes do.
So just for the hell of it,
thought I'd demonstrate it here.
Here's the light. Here's a piece of paper.
Let's play it.
Boop. All right. There it is, instantly on.
I just dropped that to prove that it was in slow-mo.
-
Gav:
I thought a good way to demonstrate just how fast
100 billion plus frames a second is,
we could just look at some of our old footage
and determine how long it would have taken
at 100 billion frames a second,
or 10 trillion.
All right, let me pull something up.
Lightning strike.
One of the fastest things
we've ever filmed previously
before we immediately beat it.
If we were to film this at 100 billion frames a second.
to watch the whole clip played back at 24
would take almost four months.
- Four months? - Yeah.
And it's just happening right there.
Gav:
And if somehow we were able
to film this at 10 trillion frames a second,
the whole strike from beginning to end
would take 32 years.
Imagine the length of that storm.
I can actually simulate exactly what that would look like
if filmed at 10 trillion.
Here we go, and it's playing now.
That's exactly what it would look like.
- Flippin'-A. - All right, another clip?
No, no. Watch the whole thing.
Okay.
- 32 years. - That should take us into retirement.
Yeah, I think so.
( no audible dialogue )
Next clip. Remember this bad lad?
Dan:
Gav:
There it is hurtling through the air.
If we'd have filmed this
at 100 billion frames a second,
from the muzzle to when it goes out
of the end of frame would take eight years.
Well, that would kind of defeat the object
of having a tank firing at something.
They'd just be, like,
"I guess I'll move out of the way."
You could serve two presidential terms
before it went out of frame.
Now just for giggles,
it's pretty easy math--
you just add two zeroes.
If we filmed it at 10 trillion,
800 years from beginning to end.
So, like, quite a few Queen Elizabeths.
And finally, the human blink-- specifically, yours.
You can tell it's mine because of the rogue brow.
- Gav:
Gav:
if shot at 100 billion, it would take 19 years
for you to close and open your eyes.
( Dan gasps )
Gav:
It would be like I'd be just about
to celebrate the millennium, and then I'd be like,
"Whoa!"
"3, 2, 1! 2019?"
You blinked and missed the millennium.
And absurdly, if we filmed this
at 10 trillion frames a second,
the most boring video ever,
it would take 1,900 years
for you to open your eyes again.
So, I'd just start blinking
when Jesus was cutting around.
I'd open them up and it would be World War I.
- Pretty much. - Right.
That's a great way of imagining that.
And just think, in all that time,
a few photons of light would just be like,
"Ah, there we go," like it was nothing.
That was honestly an absurd episode.
To take something that-- you know, everyday time, we're used to it,
but to take it to that extreme level,
you could barely even get your head around. I quite liked it.
I liked how much it messed with my head.
Me, too. I quite liked how they were telling us
about the real world applications
it could be used for in the future,
like the police might want to use it
to see around corners with that lidar.
Like the sonar where they fire light out
and bounces off all the surfaces
and they see people around the corner.
Yeah, or easily being able
to see through skin with one picture.
Yeah, you can see how a wound is healing
or you can basically take a MRI with your cell phone.
It makes me slightly terrified
about the future of surveillance technology,
but, you know, we'll see what happens.
Hopefully, you enjoyed that video.
Make sure you check out other episodes
from "Planet Slow Mo."
and you can subscribe to us,
the Slow Mo Guys, if you want.
The episodes aren't usually that heavy, I promise.
Those guys were so smart and they wore lab coats.
I feel like I should just be, like--
- We should take ours off. - Just take it.