Sunday, January 20, 2013

Random X-ray photos

24 comments:

  1. Okay Ben, this has to be one of the coolest things ever! Not many people have this capability in their garage! This is a different technique than your backscatter images isn't it? Can't wait for your next video.

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  2. Jaw dropping! Any thought to DIY X-ray fluorescent spectrometry? Imagine the power to see inside stuff AND know exactly what materials it's made of...

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  3. Thanks! These images are standard transmission X-rays. Spectrometry would be awesome -- too many cool projects!

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  4. Very impressive, great quality.

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  5. Any idea why the lenses in the DSLR pic are blocking the x-rays so much? Are they coated with with something or is that just too much glass to go through?

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  6. Anonymous, yes the glass is pretty dense and the X-ray beam is only 50KV at 1mA. It would be nice to have an X-ray beam with higher energy.

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  7. Ok, I would like to build an x-ray but safety is an issue. Are there some good references that I could start looking at? I have a friend that has an old dental x ray unit and it might make a good source but it all comes back to safety. Maybe a thick concrete box (12 or 16 inches) and leaving the room would be a good start (operating the machine remotely).

    Thanks for all the work you have done I really have enjoyed your posts.

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  8. tocs, I don't know of any good introductory safety references for X-rays. Lead is a very effective shielding material, but steel is good too. Notice how the airport baggage scanners are built: It's a tunnel, but the ends have to be fairly open to allow the baggage to pass through, so the manufacturers use lead-coated fabric strips. You don't need 12 inches of concrete -- 3mm thick lead will stop 99.97% of 80KeV X-rays. There is a handy android app that calculates attenuation for all elements. You can get lead sheet at mcmaster.com. Also, you can use a Geiger counter to detect stray X-rays, but a scintillation counter or ion tube would be even better.

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  9. Thanks for the information. Doing some research on radiation shielding, I came across the wikipedia article on the subject (Radiation_protection). There is a small table about Halving thicknesses. It says that the halving thickness for lead is 1cm (0.4 in). How does this relate to the 3mm of lead stopping 99.97% of 80KeV X-rays?

    I do not mind the idea of doing my own research but it is like having to learn a whole new disciple. I suppose this is why so much commercial equipment is so expensive. You pay for some one to tell you "This is safe" or "This will do what you want."

    I just put in a bid on ebay for an x-ray film cassette. It might be a little while before I feel comfortable using it but I think I can get there.

    By the way I also really like your tomography set up. I became interested in tomography years ago after seeing it in the hospital. When ask how it worked I was told by every one "Its just like an x-ray." That was a little frustrating because the CAT scanners use x-rays but they are not like a regular x-ray. A few years later I saw a nice demonstration of how cat scanners work at Auto Rib Cage Projection, in case any one is interested.

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  10. I goofed up an got the "Auto Rib Cage Projection" wrong.
    This should work http://www.colorado.edu/physics/2000/tomography/auto_rib_cage.html

    It was nice a few years ago but right now it is not working on my Linux machine. Will have to look for the proper plug-in.

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  11. Did the xrays corrupt the data on your netbook harddrive? Also is there any chance that xrays might induce some current in electronics that could damage them?

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  12. timelessbeing, X-rays will not induce currents or corrupt data on a hard drive. X-rays can expose photographic film -- especially sensitive high-ISO film.

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  13. tocs, the "radiation halving distance" from Wikipedia is probably referring to much higher energy gamma rays. The 80KeV X-rays do not penetrate mass as easily as gamma rays, so less shielding is needed. Use the android calculator or get the data yourself online from NIST (free).

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  14. All right, clearly I'm an idiot... what's the last image of?

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  15. Anonymous, the items are:

    TV remote control

    Canon DSLR camera

    Wireless headphones

    Asus netbook computer

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  16. Hi Ben,

    Do you think you can you do a post showing some examples of photos taken at different voltages? I'm putting together my own xray setup but I'm starting out with just a 25kV power supply and want to know what if anything I can capture with such low voltage. I haven't found much info on the web relating to this, and think it'd be an interesting experiment.

    Thanks!

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  17. Unknown, that is a really good idea. It would be a sort of "color" image showing penetration of different wavelengths.

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  18. fwiw, recent x-ray renovation where I work involved installation of new lead lined gypsum (drywall) board.
    This stuff is available. I have no idea of price.

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  19. Hello Ben, how did you take the picture? Are you aiming the camera straight to the x-ray tube, with the item in the middle? Pic taken in the dark? Or is there a phosphor screen in between the camera and the item?

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  20. Admin, the camera is on the same side of the fluorescent screen as the X-ray tube. I've corrected the perspective distortion in the image in Photoshop since the camera will not get a straight head-on view with this arrangement. The picture was taken in a very dark room, and the exposure was about 30 seconds at ISO800.

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  21. Hi Ben, your xray of the camera is a fantastic image. Would you mind if I printed it out and used it in the backdrop of a short video? I would really appreciate it.

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  22. Philip, you can use the image for educational or non-commercial use.

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  23. Where did you get the fluorescent screen and how much did it cost?

    The pictures look phenomenal!

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  24. Anonymous, I bought a few different screens on eBay ($30). Search for X-ray cassette, or Lanex, or Cronex, or other terms you find via general searching.

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