[Frameworks] X-Ray motion-pictures

[alena williams]

love this!

> On 20. Nov 2019, at 07:53, Scott Dorsey <kludge at panix.com> wrote:
> 
> Okay, old guy tells stories.
> 
> 
> Back in the twenties and thirties, doctors would employ open fluoroscopes,
> with an X-ray source behind the patient and a fluorescent screen in front
> of them.  X-rays passing through the patient would cause the screen to 
> illuminate and the doctor could see what was going on inside in realtime.
> 
> Many of the old classic sequences that still show up in educational films
> such as the man eating and man voicing different vowels and consonants,
> were shot off the screen of an open fluoroscope.
> 
> This approach has some problems.... namely it takes a lot of radiation to
> get a nice bright image, and all of that radiation (not just the backscatter)
> is pointed at the doctor.  So although you can see open fluoroscopes in old
> movies where W.C. Fields has swallowed his cigar, you will not see them in
> use today.
> 
> Because doctors needed to see movement and didn't want to irradiate themselves
> constantly, a number of manufacturers made cinefluoroscope systems with a 
> Mitchell or Acme 35mm pin-registered camera movement, a very fast lens,
> and a fluorescent screen all in one package.  The high speed Leitz Noctilux
> lenses were originally designed for these applications.
> 
> These were in common use for heart imaging until maybe a decade ago, and
> if you are looking for a film image you may be able to find cardiological
> radiologists around with a film cineangography system.  These systems all
> provide full aperture 35mm images.  So if you want 16mm you'd have to get
> the lab to bump it down.
> 
> All of these systems today have been replaced with high resolution video
> systems.  The nice thing about the video systems is that they result in
> less radiation to the patient because the light sensor is faster than Tri-X.
> These systems are small and convenient enough that some cardiologists will
> have their own system rather than contracting it out to a radiologist.
> The bad thing about them is that they tend to have more smear on motion
> than the film systems because of the longer persistence phosphors.
> 
> Now... if you don't need to deal with human beings, you can pour a whole
> lot more radiation into the object.  There are a bunch of fairly inexpensive
> X-ray inspection systems for PC boards that give you realtime video with
> decent resolution.  Not very high energy radiation since they just need to
> be looking at thin board traces for the most part.
> 
> So... if I were looking to rent some time on a machine, I would ask a 
> cardiologist if they could recommend a local radiology guy, or I would
> talk to PC board fab people, depending on whether I was looking at people
> or objects.  I have only done static x-rays, not moving ones, and there
> aren't a lot of folks doing moving ones artistically today so it could be
> really cool.
> --scott
> 
> 
> lens was originally designed 
> 
> _______________________________________________
> FrameWorks mailing list
> FrameWorks at jonasmekasfilms.com
> https://mailman-mail5.webfaction.com/listinfo/frameworks