10 fps? Try a trillion fps!

[dlcx]

Very cool, so fast that it can see light travel

"That’s fast enough to produce a slow-motion video of a burst of light traveling the length of a one-liter bottle, bouncing off the cap and reflecting back to the bottle’s bottom."

(put your nerd hats on!)

http://web.mit.edu/newsoffice/2011/t...mera-1213.html

[Jim G]

Hey, that's awesome! Light-based ultrasounds? Sounds interesting...

[TomJ]

Very cool, I think the last time I read Wikipedia it was 20 billionFPS

[Zee]

How awesome is that?

Z...

[lench]

my head hurts
so does this thinig record at faster than the speed of light? or have i missed the point entirely?

[luke o]

Originally Posted by lench

my head hurts
so does this thinig record at faster than the speed of light? or have i missed the point entirely?

It's actually the worlds slowest fastest camera

From what I understand they need an enclosure, which they then fire laser pulses into which only last a few billionths of a second. The single pulse is detected by an array of tubes, each capturing different coloured light. The image is formed from putting rows of these tubes into scan lines, kind of like how old tube TV worked, line by line.

I think it actually takes them about an hour worth of pulses to put together a few seconds of real time video.

[stenchlord]

Just happened to see something about this camera when it was presented at TED. Thought I'd share it here.

[phreeky82]

That is all kinds of awesome. If they're sharing their research data as they say they are then I can see a whole lot of research booming in this field. Good on 'em!

[SyN]

cameras too big
will never fit in my pockets

[theicemagic]

It might be rudimentary in my saying so... Everything after the tomato and light in the bottle image made sense to me and seemed about right, but the 'watching light pass through the bottle' simply can't be right, or real or in fact, is completely useless and unusable for filming.

Scientifically I'm interested in this, but I also call fake on the light in the bottle and the tomato footage.
They've said one trillion frames per second which means the shutter speed 'should' be 1/1,000,000,000,000th of a second. Considering effects of the bayer filters (apparently they're using a Canon CMOS from a 5D/5D2 consumer product), what kind of ISO are they achieving to even get an image at this rate?

Additionally, the intensity of the light would be immense.
Then you'd have to consider the time it takes for the light to travel to the camera etc... What I'm getting at is if you move the camera just 1mm closer to the object, you'd probably get an entirely different result.

I'm not doubting the technology, but I doubt those two bits of footage.

[phreeky82]

Originally Posted by theicemagic

They've said one trillion frames per second which means the shutter speed 'should' be 1/1,000,000,000,000th of a second. Considering effects of the bayer filters (apparently they're using a Canon CMOS from a 5D/5D2 consumer product), what kind of ISO are they achieving to even get an image at this rate?

A 10 picosecond search gave this:

Can you capture any event at this frame rate? What are the limitations?
We can NOT capture arbitrary events at picosecond time resolution. If the event is not repeatable, the required signal-to-noise ratio (SNR) will make it nearly impossible to capture the event. We exploit the simple fact that the photons statistically will trace the same path in repeated pulsed illuminations. By carefully synchronizing the pulsed illumination with the capture of reflected light, we record the same pixel at the same exact relative time slot millions of times to accumulate sufficient signal. Our time resolution is 1.71 picosecond and hence any activity spanning smaller than 0.5mm in size will be difficult to record.

and

What are the challenges?
Fastest electronic sensors have exposure time in nanoseconds or hundreds of picoseconds. To capture propagation of light in a tabletop scene we need sensor speeds of about 1 ps or one trillion frames per second. To achieve this speed we use a streak tube. The streak camera uses a trick to capture a one dimensional field of view at close to one trillion frames per second in a single streak image. To obtain a complete movie of the scene we stitch together many of these streak images. The resulting movie is not of one pulse, but is an average of many pulses. By carefully synchronizing the laser and camera we have to make sure each of those pulses look the same.

http://web.media.mit.edu/~raskar//trillionfps/

[theicemagic]

So basically it's a really blurry photo of the light propagation... That certainly sits a lot better with me.