Everyone knows light exposes film, but other forms of radiation do as well-a fact you can use to take pictures in some pretty unusual ways.

It's also how radioactivity was first discovered. In 1896, French physicist Henri Becquerel stored some x-ray film in a drawer along with a uranium rock. He suspected that uranium might emit strange rays when exposed to sunlight, but this sample had been kept entirely in the dark, so he was surprised to find, on developing it, that the mineral had exposed the film. The discovery of natural radioactivity won him a Nobel Prize.

It's not hard to repeat Becquerel's experience at home with standard film. I took apart a 10-pack of Fujifilm ISO 3000 instant film and wrapped each piece in tinfoil. This must be done in absolute darkness because 3,000-speed film is extremely sensitive. (I sacrificed the first pack practicing in the light.)

Next I set a big, flat butterfly-shaped earring directly on top of the wrapped film. I suspended the most radioactive thing I have, a small radium puck from an old classroom set, several inches above the earring. This allowed the radiation to shine through it and onto the film, exposing it right through the foil wrapper. Then I developed the film by pulling it through the rollers of an old Polaroid camera (once again, in complete darkness).

This exposure took about 36 hours, determined by trial and lots of error. If you're willing to wait longer, less-radioactive sources work too, even common salt substitute. Yes, sodium-free salt (potassium chloride) is sufficiently radioactive (from the isotope potassium-40) that after several months, a saltshaker-ful will form an image on film. Provided you don't forget and eat the radioactive source on your breakfast.

Achtung! Stronger radiation sources such as radium watch hands, and any source that's flaking off fine particles, should be handled with care to minimize exposure and avoid contamination.

Photo credit: Mike Walker

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[Hundertmark via BoingBoing]

We can only assume that while some poor boy with an unconfirmed fractured tibia had to wait i excrutiating pain for a hospital's only x-ray room to open, Flickr member Reintji had locked the doors from the inside as he tossed forth a pile of vintage gaming equipment to be scanned despite its inherent and shameless lack of medical insurance.

Fast forward a few weeks, and an HMO lacky is approving the expenses of Mr. Play Station the Third. Then just for a moment, the little guy claims a victory over mega corporations...while an even littler guy nurses his still-broken leg. [Flickr via AcidMods via technabob]

Apparently the trials at 6 airports have gone so well that the TSA would like to have all passengers "go through the whole-body imager instead of the walk-through metal detector." In other words, everyone who gets on a plane will be seen quasi-naked.

The TSA is quick to remind the public that the technician is "off-site" and unable to associate your grey naked body with your real, grey naked body.

Swapping all metal detectors to whole body scanners should make that 3oz liquid rule a thing of the past, but with each scanner running $100,000 to $170,000 apiece, the upgrade won't exactly be free. And really, I think the TSA should be paying me if they expect to see my naked behind. At least then I'd know the money was worth it. [NYT and Budget Travel and Getty Images]

The researchers believe that this "technology" could eventually be refined to make inexpensive medical devices for developing countries. They have even applied for a patent that would cover such devices. In the meantime, using Scotch tape in normal situations should not produce any harmful effects, although one researcher on the project noted: "If you're going to peel tape in a vacuum, you should be extra careful." But "I will continue to use Scotch tape during my daily life, and I think it's safe to do it in your office. No guarantees."

"No guarantees?" I would expect media fear mongers to run with that one. "What everyday household item causes cancer? We'll tell you at 11." [CNN and Wired Science]

Pathfinder is currently developing two "checkpoint friendly" models: one wheeled trolley with a removable laptop case, one a briefcase that reveals the laptop when it's unzipped. These new foam and nylon cases will set you back between $100 and $200. Targus's X-rayable cases vary from a $39 backpack and a $100 business traveler version. And there are at least four or five other manufacturers also submitting prototypes to the agency for checking.

But there's still a catch, of sorts: the TSA is not certifying these bags, and asks that manufacturers use terms like "checkpoint friendly" instead, and avoid buckles pockets or zips in the design. Does that mean your impractical bag won't seal securely and some officious security guard may still make you fish out your laptop anyway, as he doesn't believe it to be "friendly" to the X-ray machine? Time will tell. [NYTimes]



[Image: Nick Veasey]

First of all, photodiodes are attached to a TFT substrate produced using its proprietary amorphous silicon technology. The X-rays are detected photon by photon, before being converted into visible light, which is converted in turn to electrical signals that can be displayed as diagnostic images on a flat panel screen.

The machine also has an image enhancement function to eliminate almost all of the digital image noise interference, in order to provide the highest radiography sensitivity in the industry. The FPXD will not just be confined to medical use, as Samsung has plans to adopt the technology so that it will work with CAT scans, airport security and building inspections. [Samsung Press Release]

The process, called passive millimeter-wave technology, currently provides "somewhat fuzzy" grayscale images, but the researchers are working to get the quality up so you can really see those nipples stand out. –Adam Frucci

The Inquirer [via Ubergizmo]