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Rob Hummer gave a talk at Cine Gear Expo 2011 about how film and digital cameras catch light.

He makes a handful of extraordinary claims about digital sensors - including a claim that you get dead pixels on camera sensors by bringing them on aircraft due to gamma radiation and that there's a cover up by camera makers about it.

There's a little problem though with digital cameras, I promise you.

Anyone ever take their cameras on an airplane? Ok, every time you do that you kill photo sites on your camera, because when Canon, Nikon, Casio, Panasonic ship cameras in North America, they do it by boat, and that's because you need about - at altitudes of 20,000 feet and higher - you need about 125 feet of concrete to shield yourself from the gamma rays of higher altitude. They don't hurt us, but gamma rays induce voltages in sensors that fry our pixels.

He goes on to give an anecdote about a set of cameras for a film shoot that were damaged in a 12-hour flight.

At DALSA, when I said we should tell people about this, they said "Oh no, we don't want people to know about this, because there will be a big class action lawsuit [...]

He explains software on the camera hides the damage caused by dead pixels, and that film is immune to gamma rays.

Considering people have been carrying digital cameras on airplanes for at least the last 15 or so years - do gamma rays actually damage a modern, or less modern digital sensor. Is film immune to this effect?

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    Clearly Hummer is confusing gamma rays with cosmic rays, which are completely different things. Also, he seems to think that the higher the shielding needed to stop a ray, the higher the chance a ray will interact with a camera. The opposite is true since "shielding" and "scattering" are the same thing, at their heart. – Sklivvz Jan 5 '18 at 10:05
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    It is also worth to note that it is very common to use the sea to transfer cargo around just because it is cheaper, not because there is some weird gamma effect thingie going on. And how the hell satelittes work, then? I doubt we put so much concrete in orbit to shield then, and last time I checked Hubble didn't use film. – T. Sar Jan 5 '18 at 17:13
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    @T.Sar Hubble get its camera replaced every so many years. WFPC2, one of its main cameras, was replaced a few years back because it had a bunch of hot pixels. Satellites that can't be reasonably serviced have relatively short operational lifetimes. Correcting for a few bad pixels in software is no big deal, and always done as part of the image reduction process to get rid of data from bad pixels. – KAI Jan 5 '18 at 18:43
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    @JourneymanGeek I think you are misunderstanding the claims about software corrections to bad pixels. When they say "hide" bad pixels, they mean that they make them go away because that's what any reasonable person would want. It isn't some secret or conspiracy. Procedures for doing this go under names like "pixel mapping", and are advertised features of cameras. – KAI Jan 5 '18 at 19:01
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    No, film is not immune to gamma rays. On the contrary: photographic film (or rather: plates) is how gamma rays were first discovered! The claims here are bullshit because they ignore the fact that we are always subjected to radiation, so called background radiation. At cruising altitude in an airline, there is slightly more radiation, yes. But apart from a slightly higher intensity, there is nothing magical about that, and it does not warrant a huge cover-up due to billions of pixels dying. – MichaelK Jan 8 '18 at 12:05

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