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High speed X-ray video: jumping beans, wind-up toys and more(youtube.com)
60 points by surprisetalk 7 days ago | 21 comments
  • bkraz3 days ago

    I may have the opportunity to use a much higher framerate camera in the future. Please leave suggestions for things that are fairly transparent to x-rays (no metal, or very thin small internal parts), and demonstrates the utility of high speed capture (typically things breaking, bouncing, shattering). The last requirement is that the object be very small, just 1 to 2 cm long. Since learning about ptycography, I may try that as well since x-ray ptycography is one of the real world uses for these sensors.

    • CamperBob22 days ago |parent

      - Aim a few watts' worth of laser light at a popcorn kernel, maybe. Might be amusing to capture the resulting kinetics when it pops.

      - Put a crystal of something on a turntable and see if you can capture a video of its scattering angles. Bonus: read the movie and turn it into a 3D model for viewing.

      Did you ever XRF that windup toy to see what it was contaminated with? I'll throw in my lot with one of the commenters and guess "Lead."

    • s0rce3 days ago |parent

      I thought the insect breathing work at the synchrotron was cool https://www.science.org/doi/10.1126/science.1078008

    • jcims3 days ago |parent

      I wonder if you could blow some fine mesh aluminum/iron powder through a small whistle to see any of the airflow effects.

      Spurious xray emission from triboelectric effect.

      Phase change of various materials changing absorption characteristics.

      Capacitor discharge.

    • Python32673 days ago |parent

      Here's an interesting one, if the equipment is sensitive enough you could test if you can see the difference in air densities as a .22 caliber bullet passes by.

    • SweetSoftPillow3 days ago |parent

      Brookesia nana aka nano-chameleon.

    • shellfishgene3 days ago |parent

      This may be a bit hard, but jumping insects like locusts and crickets?

    • SweetSoftPillow3 days ago |parent

      Hummingbird

  • rdtsc3 days ago

    That's wild they have a high speed 8K photon counting device for x-rays now. It's not the one he tested but it's the latest one the company has https://www.dectris.com/en/detectors/x-ray-detectors/eiger2/

    It's also neat how he describes how the acquisition works: 32bit tiffs, pci card, real-time linux, and a special rack-mounted server.

  • echelon3 days ago

    I got nervous watching him put his hand in front of the machine.

    You don't want to subject yourself needlessly to ionizing radiation. A little here and there is probably okay at small doses and for valid reasons, but it all adds up over a lifetime.

    He didn't mention how much X-ray radiation this puts out in the first half or so of the video. I worry it's more than a medical photograph as it's continuous high sample rate video, but I'm not an expert. Would be curious to know.

    Also curious about the shielding and leaking.

    Don't damage your DNA if you don't have to. This is a cool, semi-educational video. I don't think I'd take the same risk though.

    • rdtsc3 days ago |parent

      > He didn't mention how much X-ray radiation this puts out in the first half or so of the video. I worry it's more than a medical photograph as it's continuous high sample rate video, but I'm not an expert. Would be curious to know.

      > Also curious about the shielding and leaking.

      If you'd watch the video the last part explains exactly that. The energy levels involved, how the beam is stopped, how backscatter is checked. He is definitely no dummy who just found an x-ray machine in a dump and just powered it up for clicks and giggles.

    • eig3 days ago |parent

      Be rest assured Ben’s previous job was in the medial imaging industry. While he worked on MRI machines rather than ionizing radiation, I think he’s very well aware of the dangers of X rays and has many projects dealing with ionizing radiation. There’s a lot of bad safety science YouTubers, Ben isn’t one of them :)

      Funny thing: it’s actually rare to get radiation damage to human hands and feet since there’s not too much growing tissue there!

      • scythe3 days ago |parent

        >there’s not too much growing tissue there!

        On the contrary, I was told stories in school that old IR doctors used to lose the hair on their hands after using the fluoro for years. The fingernails are also radiosensitive.

        The main reason that X-rays of the hands and feet are usually very low risk is because the beam intensity (dose) required to penetrate the small amount of tissue is very low. Because the video uses a high-sensitivity detector (photon counter) the dose may be even less than usual. However, it would still be a regulatory violation if you did it in a hospital.

    • zzlk3 days ago |parent

      I think it's probably not true that it all adds up over a lifetime. That's the model that is widely used but there's some good evidence to suggest it's not accurate.

      see: https://en.wikipedia.org/wiki/Linear_no-threshold_model

    • scythe3 days ago |parent

      >I worry it's more than a medical photograph as it's continuous high sample rate video, but I'm not an expert. Would be curious to know.

      Typical fluoro skin entrance exposure rate to go through someone's hand is on the order of 1-3 millisieverts per minute. With a more advanced detector (like this one) it may be lower, but increasing the frame rate or resolution will tend to require higher dose rate. The associated risk of skin cancer is quite small. But please be aware that unnecessary X-Ray imaging of living things is against the law in most jurisdictions.

      • SoftTalker3 days ago |parent

        I've wondered how much the average X-ray dosage dropped since they stopped using film and switched to detector-based imaging. Anyone know?

        • scythe3 days ago |parent

          You can compare diagnostic reference levels (DRLs) from different years for the same exam; these correspond to the 75th percentile patient dose for a particular imaging study. It can be a little annoying to find older DRLs (I just tried).

          NCRP 172 (published 2015) provides a direct comparison of digital to film for some examinations. For upper GI fluoroscopy without oral contrast the DRL for film is 3.9 mSv and for digital is 1.5 mSv. I think this is roughly typical.

  • lacoolj3 days ago

    Not only is this incredibly cool, but it bridges my knowledge of x-ray (CR/XR, in this case, DR) even further. I work for a medical imaging company and we actually sell and promote our digital radiography machine that will do this, but for humans (at a much, much slower rate, but enough to be useful in medical diagnostics).

    I had never considered an application of use outside of medicine.

    So, my day is now accounted for. In addition to "overdue training" on things I already know, I will be youtubing all the x-ray, MRI, ultrasound fun things that you would never see otherwise.

    Thank you OP!

    • cycomanic3 days ago |parent

      Please post a link to your YT channel so we all can take part in the fun.

  • pmontra3 days ago

    A Motif interface from the early 90s at about 10:00 in the video. That X-Ray detector has probably a very long history.

  • world2vec3 days ago

    One of the most underrated channels on YouTube.