Saw an interesting X-Ray system this week.

[Neal Chaves]

My mother broke her arm and we went to the orthopedic practice to have x-rays. The machine itself was a film type, but they were no longer using film. Instead, the technician inserted an 8X10 cassette made by Agfa, pulled the slide and made the exposure. The cassette was then taken to the back room and inserted in a washing machine sized Agfa unit and read to produce a B&W digital file. The tech told me it was a JPEG.

Then the cassette is erased and ready to use again. They also had 10X12 size cassettes. They are the same dimensions as the x-ray film holders, which are of a different design than view camera film holders. X-ray film holders did not have, or need a dark slide, but these digital ones apparently make use of one. With a sensitivity comparable to x-ray film, there is no reason they would not work in a view camera with a back made to hold them. I tried to reseach the sysem on-line but couldn't come up with much info.

[ic-racer]

Did you look here: http://www.crcpd.org/Pubs/QAC/Oct08QAC.pdf or here: http://radiographics.rsna.org/content/27/3/675.long

Personally, I'd not mess with x-rays at home Your camera lens won't focus them anyway.

Anyway I have seen small hand held devices that look like a camera that capture the image by leaving out the need for x-rays and the phosphor plate and the laser to read the plate. Apparently, since the A/D sensor is sensitive to visible light, a direct image from the lens can be captured. I hear they are quite popular.

[Neal Chaves]

Thanks Ic-racer! I thought the plates might be sensitive to visible light, as well as x-rays, like x-ray film, but they are not. There is no photgraphic application for this technology. As it says in the PDF, these plates require even higher x-ray exposure to form an image than required for film. A step backward as far as patient saftey is concerned.

[Amedeus]

What you are looking at is a flat panel X-Ray detector that is fully solid state. (I'm pretty familiar with the products ... )

http://www.perkinelmer.com/pages/050...products.xhtml

You can read more about this on the above link. This company delivers the guts, others will develop a product around it.

The technology at this point can do video x-ray. Actually quite neat to see fluid flow and moving internal organs ;-)

These plates are indeed not sensitive to visible light in the final product form. The detector though is sensitive to visible light and a scintillator is used to convert x-ray radiation into photons ...

[Neal Chaves]

Very interesting Amedeus. Resoloution is still only that of a DSLR. Nothing of benefit to the large format photographer here (yet). When you think of it, doctors have to send these image files around the hospital computer network or over the Internet. They don't need or want high resoloution, but now details that could have been seen with a loupe on an X-ray negative film are no longer available to them.

[Amedeus]

Resolution is definitely not on par with ccd/CMOS sensors for numerous reasons. Choice made of what is practical for the application. As for the detail when needed, we support other imaging techniques that can and will get you there another way.

Reality is that by now most advanced medical facilities are on digital imaging. The advantages are too numerous, not only from a storage perspective but more so from an image processing diagnostics perspective and the ability to see things real time life.

[C. D. Keth]

Thanks Ic-racer! I thought the plates might be sensitive to visible light, as well as x-rays, like x-ray film, but they are not. There is no photgraphic application for this technology. As it says in the PDF, these plates require even higher x-ray exposure to form an image than required for film. A step backward as far as patient saftey is concerned.

X-Ray film isn't sensitive to x-rays, or at least that's how it was explained to me. X-ray film was bipacked with another film that would produce light when hit with x-ray energy. That film would expose the film which would then be developed and read.

[Amedeus]

That is correct Christopher.

X-rays pass through a phosphor coating that glows and it is this light that is captured on the film. The phosphor coating is located in the film cassette. It's also this phosphor coating that a "limitation" on the detail captured on the film.

In a digital system a similar scintillator is built up, one for each (large) pixel.

X-Ray film isn't sensitive to x-rays, or at least that's how it was explained to me. X-ray film was bipacked with another film that would produce light when hit with x-ray energy. That film would expose the film which would then be developed and read.

[Tobey69]

agree that....

[Steve Smith]

X-rays pass through a phosphor coating that glows and it is this light that is captured on the film.

That makes me wonder why there is so much paranoia about putting film through airport scanners.


Steve.