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Radiation dosimeter iphone app

20 megapixel display records a few hours of nothing, then the math DSP seeks scintillation events
 
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I heard that the iphone is getting a 20 megapixel display. The 20 megapixel display records a few hours of nothing, then the math DSP seeks scintillation events

It would have been reassuring or informing at Fukushima or Chernobyl

Pretty easy to test with a smoke detector n an iphone as well.

beanangel, Apr 20 2013

Old theme on HB (reduntant to this idea) Walking_20Geiger_20Counter
[theircompetitor, Apr 21 2013]

Camera phone Geiger counter app http://hackaday.com...o-a-geiger-counter/
[mitxela, Apr 21 2013]

[link]






       Would moderate levels of radiation give any significant signal above the background "dark noise" of the camera? I suspect not. Ingenious, though.
MaxwellBuchanan, Apr 20 2013
  

       Very high speed film can detect raiation but I seriously doubt that the noise from a CMOS sensor would tell you anything.
DIYMatt, Apr 20 2013
  

       The Wiki entry for Scintillator mentions that " Polyethylene naphthalate has been found to exhibit scintillation by itself without any additives" and will probably replace plastic scintillators. Maybe even covers which light up at all the wrong times?
4and20, Apr 20 2013
  

       As [MB] says, unless the dark current noise of the camera is abnormally low (usually involving a deeply chilled camera), that will completely swamp scintillation events.
MechE, Apr 20 2013
  

       Am out of my depth, but omniWiki says that dark current noise exists in all diodes, including it seems photodiodes use for existing scintillation detectors. It may very well be the case that scintillation detectors today woudn't be sensitive to moderate levels of radiation.
4and20, Apr 20 2013
  

       Scintillation counters use a photomultiplier. This is incredibly more sensitive than a CCD. They also tend to be optimized for extremely low dark current, and don't develop thermal noise. They also have extremely high amplification, so a single event will produce a significant current.   

       iPhone CCDs, on the other hand are whatever they can get cheap off the shelf, are decidedly not optimized for either low dark current, nor for high quantum efficiency, and have no particular amplification. They also aren't chilled to reduce thermal noise, which CCDs require for high sensitivity applications. Since they tend to be optimized for fairly bright daylight, or at least require a flash, the scintillation event is almost definitely not going to be detectable.
MechE, Apr 21 2013
  

       Polyethylene naphthalate does fluoresce blue at some level of radiation which eludes me. As a complete aside, I wonder if a similar process is behind the coloured lights some people see just before an earthquake.
4and20, Apr 21 2013
  

       //coloured lights some people see just before an earthquake// Are you sure that's not the LED flashes on their smartphones as they try to film the devastation?
pocmloc, Apr 21 2013
  

       Seeing coloured lights, falling over, can by symptomatic of many things.
not_morrison_rm, Apr 22 2013
  

       As can feeling the earth move.
MaxwellBuchanan, Apr 22 2013
  

       The videos I have seen of "earthquake lights" on Youtube all seem to show iridescent clouds and/or sundogs, both of which are actually very common but seldom noticed. Another video showed (probably) a power transformer blowing up in the distance. Yet I believe "earthquake lights" are fairly well documented.   

       Does anyone have a link to a video of some non- mundane "earthquake lights"?
MaxwellBuchanan, Apr 22 2013
  

       I'll believe in pre-earthquake phenomena (lights, animal behavior, whatever) once there is a documented case of someone reporting it before the earthquake. Oh, and no documented cases of someone reporting the identical phenomenon without an earthquake following.   

       Given twitter/instagram (and the fact that earthquake reports online are now outpacing the ground wave in many cases), it seems reasonable that if these things actually happened, there should be at least a few pictures of the lights on- line.   

       The animal thing is a little harder, because pets sometimes just behave weird. There I'm looking for a statistically significant increase in "weird pet" reports prior to the quake.
MechE, Apr 22 2013
  
      
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