Super fast exposure time - BBC News

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Jul 21, 2010
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kennephoto said:
Pretty sure you can use any light, since its quite literally capturing a photo of light. You just adjust the exposure to compensate for the amount of light like we already do.

Right, so at 1 billionth of the current max shutter speed of 1/8000 s, to 'just adjust the exposure to compensate for the amount of light like we already do,' you'd need to go 36 stops higher than ISO 100. Know any cameras that can set ISO 6,871,947,673,600? ::)
 
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luciolepri said:
WOW!

It looks strange they're using a old Sigma 28-70/2,8 instead of a superfast lens, considering they need multiple exposures to get the image at that crazy fast frame rate.
Thanks to the new Sigma service, I could borrow them my Canon 50/0,95...

I think the BBC report was using that as an example. I'd be they are using their own custom optics for this. Probably. I could be wrong though.
 
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neuroanatomist said:
kennephoto said:
Pretty sure you can use any light, since its quite literally capturing a photo of light. You just adjust the exposure to compensate for the amount of light like we already do.

Right, so at 1 billionth of the current max shutter speed of 1/8000 s, to 'just adjust the exposure to compensate for the amount of light like we already do,' you'd need to go 36 stops higher than ISO 100. Know any cameras that can set ISO 6,871,947,673,600? ::)
Actually you both are wrong. You cant use any light. You need femtosecond pulsed laser source to illuminate the scene. Then streak camera, PMT or other device is used to capture reflected pulses to create a probability distribution by acquiring millions of scans and calculate arrival time of photon (extract time information). Image is then calculated and integrated for whole scene using piezo-controlled mirrors. In short for people with non-technical background, repeated measurement of scene illuminated by femtosecond spaced pulses combined with maths is used to calculate the time information at a point/line. This is then calculated for all points/lines in scene to construct an image. So its takes quite a while to construct one super-fast timelapse (counterintuitive isnt it).

Small issues getting it into Canon 1DXXX:
1) You need at least two people to hold even simplest of femtosecond lasers
2) Its a two piece assembly with micrometer beam alinment on optical table; good luck with handholding
3) You need the scene to repeat millions of times. Like if you want a video of kid running, you will need the kid to run same path millions of times (this is only for time lapse imaging; does not apply to their around the corner imaging)
and many more but I am bored.
I am sure they will overcome these problems sometime in future!!!!
Source: I use the same camera at nanometer scale. So I collect images with nanometer spatial resolution and picosecond time resolution.
 
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comsense said:
neuroanatomist said:
kennephoto said:
Pretty sure you can use any light, since its quite literally capturing a photo of light. You just adjust the exposure to compensate for the amount of light like we already do.

Right, so at 1 billionth of the current max shutter speed of 1/8000 s, to 'just adjust the exposure to compensate for the amount of light like we already do,' you'd need to go 36 stops higher than ISO 100. Know any cameras that can set ISO 6,871,947,673,600? ::)
Actually you both are wrong. You cant use any light. You need femtosecond pulsed laser source to illuminate the scene. Then streak camera, PMT or other device is used to capture reflected pulses to create a probability distribution by acquiring millions of scans and calculate arrival time of photon. Image is integrated for whole scene by integrating using piezo-controlled mirrors. In short not non-technical background, repeated measurement scene illuminated by femtosecond spaced pulses combined with maths is used to calculate the time information at a point/line. This is then calculated for all points/lines in scene to construct image. So its takes quite a while to construct one super-fast timelapse (counterintuitive isnt it).
Small issues getting it into Canon 1DXXX:
1) You need at least two people to hold even simplest of femtosecond lasers
2) Its a two piece assembly with micrometer beam aliment on optical table; good luck with handholding
3) You need the scene to repeat millions of times. Like if you want a video of kid running, you will need the kid to run same path millions of times (this is only for time lapse imaging; does not apply to their around the corner imaging)
and many more but I am bored.
I am sure they will overcome these problems sometime in future!!!!

Interesting...sounds almost like a reverse ray-tracing rendering!
 
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comsense said:
neuroanatomist said:
kennephoto said:
Pretty sure you can use any light, since its quite literally capturing a photo of light. You just adjust the exposure to compensate for the amount of light like we already do.

Right, so at 1 billionth of the current max shutter speed of 1/8000 s, to 'just adjust the exposure to compensate for the amount of light like we already do,' you'd need to go 36 stops higher than ISO 100. Know any cameras that can set ISO 6,871,947,673,600? ::)
Actually you both are wrong. You cant use any light. You need femtosecond pulsed laser source to illuminate the scene. Then streak camera, PMT or other device is used to capture reflected pulses to create a probability distribution by acquiring millions of scans and calculate arrival time of photon. Image is integrated for whole scene by integrating using piezo-controlled mirrors. In short not non-technical background, repeated measurement scene illuminated by femtosecond spaced pulses combined with maths is used to calculate the time information at a point/line. This is then calculated for all points/lines in scene to construct image. So its takes quite a while to construct one super-fast timelapse (counterintuitive isnt it).
Small issues getting it into Canon 1DXXX:
1) You need at least two people to hold even simplest of femtosecond lasers
2) Its a two piece assembly with micrometer beam aliment on optical table; good luck with handholding
3) You need the scene to repeat millions of times. Like if you want a video of kid running, you will need the kid to run same path millions of times (this is only for time lapse imaging; does not apply to their around the corner imaging)
and many more but I am bored.
I am sure they will overcome these problems sometime in future!!!!
Source: I use the same camera at nanometer scale. So I collect images with nanometer spatial resolution and picosecond time resolution.

I love CR...
 
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Jul 21, 2010
31,265
13,157
comsense said:
neuroanatomist said:
kennephoto said:
Pretty sure you can use any light, since its quite literally capturing a photo of light. You just adjust the exposure to compensate for the amount of light like we already do.

Right, so at 1 billionth of the current max shutter speed of 1/8000 s, to 'just adjust the exposure to compensate for the amount of light like we already do,' you'd need to go 36 stops higher than ISO 100. Know any cameras that can set ISO 6,871,947,673,600? ::)
Actually you both are wrong. You cant use any light. You need femtosecond pulsed laser source to illuminate the scene.

Ok, but I was being facetious. :)

FWIW, many years ago I used femtosecond laser time-resolved resonance Raman spectroscopy to study reaction intermediates of visual pigments (rhodopsin, etc.). Nd:YAG flashlamps, beamlines running across massive air tables decorated with mirrors and dichroics, fun times. I currently use a femtosecond Ti:sapphire laser (pumped with a frequency-doubled Nd:YVO4 laser) in fluorescent imaging applications.
 
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