I'm starting to think you should try to scout for some sort of xray machine, just like Mike. Might come in handy in situations like this one.
They apparently are not legal in this country, you need a permit, and can only sell 2nd hand to others with permits etc.
Here are the exemptions to Aussi X-Ray (ionizing radiation) regulations: See Part 4 of
http://www.legislation.nsw.gov.au/maintop/view/inforce/subordleg+52+2013+cd+0+NIt looks like all CRT tubes are exempted. CRTs are great generators of low-energy X-Rays, which is why the face is made of leaded glass (for viewer shielding).
For electrostatic deflection CRTs, a neat trick is to intentionally impact the beam on one of the deflector plates. Depending on the impact site and angle, it is sometimes possible to produce a nice X-Ray stream exiting somewhere on the opposite side of the tube. But you will need to crank the KV way up (60-200 KV) and the amperage way down. And periodically move the impact point to avoid burning a hole.
But a more practical approach is to simply buy an X-Ray tube. eBay is your friend: There's a bloke in Iowa who will gladly ship Down Under:
http://www.ebay.com.au/itm/C-E-I-X-Ray-Tube-OX-70-g4-Brand-New-/231619642943?pt=LH_DefaultDomain_0&hash=item35ed9b463fStriking an arc from any 60-200 KV source will create X-Rays. Ideally, the arc will be in a vacuum to limit copious UV and ozone production from an air-gap. Tungsten is the best anode material due to its ability to handle localized heating without melting.
Note: X-Rays are generally classified as "soft" (10-50 KV) and "hard" (60-200+ KV). Soft X-Rays are safest (less ionizing and less penetrating), but they tend to scatter more easily, meaning images may be both dimmer and fuzzier. In cases where the target can't be right against the phosphor screen, or is relatively dense, hard X-Rays will yield much better images. A good compromise is around 80-90 KV.
Once you have an X-Ray source and something you want an image of (the "target"), the next step is to find a way to convert he X-Rays passing through the target into an image.
For hobby use, the simplest target is a phosphor sheet, where the phosphor is X-Ray sensitive (not uncommon). Ideally, the phosphor will have a visible light emission curve with a time constant of single-digit milliseconds. The reason for these specific characteristics comes from a chain of reasoning that starts with how X-Rays are best generated from ad hoc sources: As very brief but intense pulses well separated in time. This is needed to limit localized cathode heating and thus keep the X-Rays sharply focused. It also keeps the dose rate extremely low while still permitting excellent images to be generated.
Commercially, such phosphor sheets may be called "X-Ray intensifier screens" or "X-Ray scintillator screens".
A camera is aimed at the fluorescent sheet, and an exposure is taken for every X-Ray pulse. The exposure start is delayed from the X-Ray pulse by the fluorescence latency of the phosphor, and the exposure duration is limited to the maximum expected glow rise and decay time (which can be calculated, but is best determined experimentally). Most consumer cameras with external shutter releases can be configured to capture excellent X-Ray images.
Many images will be needed, since each pulse contains relatively few X-Ray photons, even fewer of which will pass through the target. This means hundreds or thousands of pulses (and exposures) may be needed to generate a final high-contrast image. The image processing techniques used to combine the individual exposures are straightforward, and are well documented online. For a dense target, millions of X-Ray pulses may be needed, and combining them becomes a bit trickier, since stray image artifacts due to camera sensor shot noise, cosmic rays, and normal ambient background radioactivity would need to be corrected for.
It is certainly possible to create home X-Ray images both legally and safely (the main worry is HV, not X-Rays). And it is great training in both scientific investigation and engineering processes, since it is simple enough to get "interesting" initial results, but very demanding to get high-quality results.
BTW, pretty much any "continuous" X-Ray tube can be operated in pulse mode. And by some definitions, "continuous" may be pulsed at any rate above 25 Hz (continuous to the human eye). So be sure to read the find print.
Update: Here's a really simple DIY 100 KV pulse generator:
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