[HN Gopher] High speed X-ray video: jumping beans, wind-up toys ...
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       High speed X-ray video: jumping beans, wind-up toys and more
        
       Author : surprisetalk
       Score  : 53 points
       Date   : 2025-11-07 14:06 UTC (4 days ago)
        
 (HTM) web link (www.youtube.com)
 (TXT) w3m dump (www.youtube.com)
        
       | echelon wrote:
       | 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.
        
         | zzlk wrote:
         | 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
        
         | eig wrote:
         | 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!
        
           | scythe wrote:
           | >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.
        
         | scythe wrote:
         | >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.
        
           | SoftTalker wrote:
           | I've wondered how much the average X-ray dosage dropped since
           | they stopped using film and switched to detector-based
           | imaging. Anyone know?
        
             | scythe wrote:
             | 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.
        
         | rdtsc wrote:
         | > 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.
        
       | bkraz wrote:
       | 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.
        
         | s0rce wrote:
         | I thought the insect breathing work at the synchrotron was cool
         | https://www.science.org/doi/10.1126/science.1078008
        
         | jcims wrote:
         | 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.
        
         | shellfishgene wrote:
         | This may be a bit hard, but jumping insects like locusts and
         | crickets?
        
         | Python3267 wrote:
         | 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.
        
         | SweetSoftPillow wrote:
         | Hummingbird
        
         | SweetSoftPillow wrote:
         | Brookesia nana aka nano-chameleon.
        
       | lacoolj wrote:
       | 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!
        
         | cycomanic wrote:
         | Please post a link to your YT channel so we all can take part
         | in the fun.
        
       | rdtsc wrote:
       | 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.
        
       | world2vec wrote:
       | One of the most underrated channels on YouTube.
        
       | pmontra wrote:
       | A Motif interface from the early 90s at about 10:00 in the video.
       | That X-Ray detector has probably a very long history.
        
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       (page generated 2025-11-11 23:01 UTC)