bad link to the iFixit blog link
here's the correct one
http://ifixit.org/blog/7401/if...
ahh, there it is now. wasn't there when i first looked at the story
what, no link to the press release?
Film vs digital detector doses are comparable, but when you factor in repeats due to improper exposures, film is a little higher. It's not enough to make it worth switching to digital detectors based on dose considerations alone though. There are plenty more compelling reasons to switch from film to digital.
The wider dynamic range of digital detectors gives a lot of flexibility when it comes to the amount of exposure used. If not enough radiation is used, a digital detector will produce a noisier, but often still useful image. The film image on the other hand will be too light and generally non-diagnostic. If too much radiation is used, the digital detector will produce a pretty, low noise image where the film image will end up being too dark and often non-diagnostic.
It is ultimately the responsibility of the imaging professionals (radiologists, technologists and medical physicists) to develop proper imaging protocols to suit the age and sizes of the patients being imaged, not only from a radiation dosimetry point of view, but also an image quality point of view.
For a long time now the tendency, particularly with CT imaging, has been to use a one size fits all protocol for everybody.
The move to reducing medical radiation exposure has been going on for several years now. Recent high profile incidents (such as what happened with CT patients getting CT angiograms at Cedars Sinai) prompted many institutions to review their imaging protocols. The Image Gently campaign has worked towards getting institutions to develop pediatric specific imaging protocols for several years now. For procedures involving potentially high radiation exposures, radiologists review and protocol the requests to make sure the requested exam fits the clinical indications. Outpatient imaging centers performing CT imaging need to get their scanners accredited in order to get Medicare reimbursement. Accreditation by the ACR (American College of Radiology) places dose limits on several types of scans. If a site's protocol results in a radiation dose that exceeds the limits, they fail accreditation and need to adjust their protocols.
The FDA can and should require manufacturers provide the tools to enable imaging facilities to monitor and record the amount of radiation given during a procedure, but it needs to be the responsibility of the users to make sure the imaging equipment is used properly on patients.
is the one that you carry with you.
for a photography newbie, i'm of the opinion that the specific camera doesn't really matter. They're all more or less the same anyway. what's most important is finding one that you'll want to carry around with you and use. the more you use it the less newb you'll become over time. you'll learn things and by the time you're ready to upgrade you'll know what to look for.
Thanks for all the work you put into
it's been my main source of news and laughs for most of the 14 years it's been around.
Best of luck with whatever comes next
and rather enjoyed it. The ending was different from what I expected or thought it might be, but given the nature of apes, a much more fitting ending than the one I imagined.
the only people the apes kill are the ones that deserved it. on the other side, lots of apes were killed by people.
the apes don't really need to get rid of people to take over the planet. humans take care of the problem all on their own
This has been known for decades. The more time at altitude the LESS you should be exposed to other forms of radiation. That's why they ask you questions about flying before any medical procedure involving radiation.
I'll bet the pilots are incredibly pissed about all these scans because for one thing it can reduce their legal flight time.
In the US, medical exposures are not counted against occupational exposure.
To make things worse these things are not just your normal transmission x-ray where you just want to see what photons make it to the sensor and the dark spots tell you where the dense stuff is. What these scanners are doing is providing far more radiation with the aim of getting atoms to absorb and re-emit photons - effectively making you radioactive while the scanner is on. The idea behind that is the wavelengths of the re-emitted photons can be used to determine what elements are present, find metal and perhaps find explosives. Because that really adds up to a shitload of radiation if it's going to scan all the way through you the dose is cut back and you just end up with the skin being exposed to quite a lot and no ability to sense internally hidden explosives.
No. The x-rays being detected are those that scatter off the person being scanned. They are *not* making anybody radioactive in any way. There is no way scattered x-rays are going to tell you the elemental composition of anything. Density, but not composition.
It is also not a "shitload of radiation". If these machines were detecting transmitted radiation instead, that would actually require *more* radiation exposure and would operate more like x-ray units found in hospitals.
The biggest difference between time and space is that you can't reuse time. -- Merrick Furst