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4.8 million frames per second is wild. Currently the phantom can achieve I think 1.5M fps in black and white with a "postal stamp" resolution. I wonder what res

by h1fra 3y ago

4.8 million frames per second is wild. Currently the phantom can achieve I think 1.5M fps in black and white with a "postal stamp" resolution. I wonder what resolution this camera could output but I guess it's probably smaller than < 120px.

xattt 3y ago
From Wikipedia: > 1,750,000 frames per second at a resolution of 1280 x 32 It’s just a slit! This is wild it’s even possible.
credit_guy 3y ago
It's wild indeed. Maybe even wilder is that a camera capable of taking on million frames per second was developed in 1940. It was called the Repatronic camera [1],[2]. I can't provide a link, but I read in the book "Dark Sun" by Richard Rhodes that they had a 3.5 million frames per second camera when they detonated the first thermonuclear bomb, Ivy Mike, in 1952. I found in a different place that the guy who built this camera was a certain Berlyn Brixner. The wikipidia page for Berlyn Brixner [3] does not mention this detail, unfortunately. [1] https://www.nnss.gov/docs/fact_sheets/DOENV_1136.pdf https://www.nnss.gov/docs/fact_sheets/DOENV_1136.pdf [2] https://en.wikipedia.org/wiki/Rapatronic_camera https://en.wikipedia.org/wiki/Rapatronic_camera [3] https://en.wikipedia.org/wiki/Berlyn_Brixner https://en.wikipedia.org/wiki/Berlyn_Brixner
davidhyde 3y ago
They should probably have indicated how many frames they can capture too. > The team created a DRUM camera with a sequence depth of seven frames, meaning that it captures seven frames in each short movie. Seems like their movies could possibly only be 7 frames in length so not really comparable to Phantom type cameras which can capture a lot more content. Still, it’s great to see the mirror tech used in DLP projectors having other uses. Some 3D resin printers use it too but that’s still projection I guess. I think those dlp mirror chips are amazing and probably fascinating to hack around with.
- h0l0cube 3y ago
  > He realized that rapidly changing the tilt angle of periodic facets on a diffraction grating, which can generate several replicas of the incident light traveling in different directions, could present a way to sweep through different spatial positions to gate out frames at different time points. My guess is the ‘sequence depth’ relates to the amount of diffraction gates. So perhaps all that’s needed is an ultrafast shutter to string together a long ‘movie’
  - foota 3y ago
    The diffraction grate (not gate, it is gating but it's a grate) has a number of possible diffraction modes dependent on the angular range of the DMD (an array of tiny mirrors that flip back and forth between two positions). In this case, there are 7 possible diffraction modes, and the sequence depth (the term for the number of frames) is 7 in reflection of this.
    - h0l0cube 3y ago
      > not gate, it is gating but it's a grate I didn't mean to conflate the two, it's gating through a... 'grating'. Though the article and the paper do use the term 'diffraction gating'. > "Luckily, it is possible to accomplish this type of swept diffraction gate by using a digital micromirror device (DMD)—a common optical component in projectors—in an unconventional way," said Liang. "DMDs are mass-produced and require no mechanical movement to produce the diffraction gate, making the system cost-efficient and stable." "Diffraction-gated real-time ultrahigh-speed mapping photography" https://opg.optica.org/optica/fulltext.cfm?uri=optica-10-9-1223&id=538060 https://opg.optica.org/optica/fulltext.cfm?uri=optica-10-9-1...
      - foota 3y ago
        The terminology here is confusing, you could say it really grates on me.

by h1fra 3y ago

xattt 3y ago

From Wikipedia: > 1,750,000 frames per second at a resolution of 1280 x 32 It’s just a slit! This is wild it’s even possible.

credit_guy 3y ago

It's wild indeed. Maybe even wilder is that a camera capable of taking on million frames per second was developed in 1940. It was called the Repatronic camera [1],[2]. I can't provide a link, but I read in the book "Dark Sun" by Richard Rhodes that they had a 3.5 million frames per second camera when they detonated the first thermonuclear bomb, Ivy Mike, in 1952. I found in a different place that the guy who built this camera was a certain Berlyn Brixner. The wikipidia page for Berlyn Brixner [3] does not mention this detail, unfortunately. [1] https://www.nnss.gov/docs/fact_sheets/DOENV_1136.pdf https://www.nnss.gov/docs/fact_sheets/DOENV_1136.pdf [2] https://en.wikipedia.org/wiki/Rapatronic_camera https://en.wikipedia.org/wiki/Rapatronic_camera [3] https://en.wikipedia.org/wiki/Berlyn_Brixner https://en.wikipedia.org/wiki/Berlyn_Brixner

davidhyde 3y ago

They should probably have indicated how many frames they can capture too. > The team created a DRUM camera with a sequence depth of seven frames, meaning that it captures seven frames in each short movie. Seems like their movies could possibly only be 7 frames in length so not really comparable to Phantom type cameras which can capture a lot more content. Still, it’s great to see the mirror tech used in DLP projectors having other uses. Some 3D resin printers use it too but that’s still projection I guess. I think those dlp mirror chips are amazing and probably fascinating to hack around with.

h0l0cube 3y ago
> He realized that rapidly changing the tilt angle of periodic facets on a diffraction grating, which can generate several replicas of the incident light traveling in different directions, could present a way to sweep through different spatial positions to gate out frames at different time points. My guess is the ‘sequence depth’ relates to the amount of diffraction gates. So perhaps all that’s needed is an ultrafast shutter to string together a long ‘movie’
- foota 3y ago
  The diffraction grate (not gate, it is gating but it's a grate) has a number of possible diffraction modes dependent on the angular range of the DMD (an array of tiny mirrors that flip back and forth between two positions). In this case, there are 7 possible diffraction modes, and the sequence depth (the term for the number of frames) is 7 in reflection of this.
  - h0l0cube 3y ago
    > not gate, it is gating but it's a grate I didn't mean to conflate the two, it's gating through a... 'grating'. Though the article and the paper do use the term 'diffraction gating'. > "Luckily, it is possible to accomplish this type of swept diffraction gate by using a digital micromirror device (DMD)—a common optical component in projectors—in an unconventional way," said Liang. "DMDs are mass-produced and require no mechanical movement to produce the diffraction gate, making the system cost-efficient and stable." "Diffraction-gated real-time ultrahigh-speed mapping photography" https://opg.optica.org/optica/fulltext.cfm?uri=optica-10-9-1223&id=538060 https://opg.optica.org/optica/fulltext.cfm?uri=optica-10-9-1...
    - foota 3y ago
      The terminology here is confusing, you could say it really grates on me.