Yikes! Cosmic rays ate my pixels!

DavidH said:
Most of the big pro tv cameras have an abillity to map out any affected pixels - an extended black balance identifies the pixels...Have no idea whether any digital stills camera has the same ability but I doubt it at the consumer end of the market at least.
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The firmware update for the Epson R-D 1 included a bad-pixel-mapping feature, and my Olympus C4040 point-and-shoot has it too. On the other hand, my Nikon D100 does not. Those are the only digital cameras I have handy for examination.

It would be interesting if some print or online publication could do an authoritative survey to find out (1) how big a problem this is, if any, and (2) if it's a problem, which cameras have a feature to address it and which don't.

Of course, even if you can map out bad pixels, you still lose their ability to contribute to the image, so that's not a perfect solution -- but it's better than no solution.

Film isn't immune to this problem, either -- I recall reading a Kodak publication warning not to rely on T-Max P3200 film after its marked expiration date, even if it's been kept in a freezer, because its high sensitivity makes it susceptible to fogging by cosmic rays.

I don't travel by air very much (the earth's atmosphere dissipates most of the energy of cosmic rays, so they don't have much effect on the ground) so I'm not too worried -- but if I traveled by air a lot and were about to invest in an expensive digital camera, I guess I'd want to know whether this was going to be a potential issue.

For that matter, I wonder if the high-energy scanners now used to inspect most checked luggage might also be able to knock out a pixel or two occasionally...
 
Abbazz said:
Cosmic rays can also adversely affect film. And there is no way to protect the stock in your freezer against those radiations (see this thread).

Cheers,

Abbazz
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You could put your freezer in an old mineshaft two miles down.....
 
A good Tilley hat will protect you against neutrino's Im told. Keep your film under your hat...:D:D
 
jamiewakeham said:
Oh, dear... awful jokes! Am I not the only physicist on this board, then?

Jamie
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I think you may be, I colour-in for a living, my son’s doing is A level at the moment!!
 
jano said:
Wouldn't the ray affect the sensor only if it were on/powered?
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It seems not. Apparently cosmic ray hits can "fog" a digital image during exposure (this is an ongoing issue for operators of space-based telescopes) but highly energetic ones can also hit a sensor hard enough to knock out individual pixels permanently. I didn't save them, but there are a bunch of web links on this type of thing.
 
Don't go too close to the sun, a nuclear blast, or a particle accelarator and you and your M8 will be fine. I hope. :p
 
Well this is just ducky. $5000 for a camera and every time you take it on a trip some pixels get killed off. I wonder how many pixels will already be dead by the time the M8s are flown from Solms to distributors around the world, then flown to the dealers, then flown to the customer. Send it back under Passport you say? Great, since Solms will be the only place that can fix it at least to start, that's a 9 hour plane ride back to NJ and a 3 hour plane ride to Chicago, so it's like Sysyphus pushing the rock uphill :bang: Seems like a good reason to stick with $800 one-generation-past Canon refurbs.
 
Ben Z said:
Well this is just ducky. $5000 for a camera and every time you take it on a trip some pixels get killed off. I wonder how many pixels will already be dead by the time the M8s are flown from Solms to distributors around the world, then flown to the dealers, then flown to the customer. Send it back under Passport you say? Great, since Solms will be the only place that can fix it at least to start, that's a 9 hour plane ride back to NJ and a 3 hour plane ride to Chicago, so it's like Sysyphus pushing the rock uphill :bang: Seems like a good reason to stick with $800 one-generation-past Canon refurbs.
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I wouldn’t worry about it one or two layers of aluminium foil offers the same protection from neutrinos as 1/4" lead shielding.
 
Sparrow said:
I wouldn’t worry about it one or two layers of aluminium foil offers the same protection from neutrinos as 1/4" lead shielding.
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There is, however, a peculiar neutrino shielding property of ordinary brown paper if wrapped around a Leica M8. This property is mediated by affixing an antineutrino catalyst seal to the outside of the paper and coding it with a set of codes. The sealed camera must then be put in a protective box.

Catalyst seals are available from CERN in Geneva and from the Kamioka research plant in Japan; however, research shows that ordinary gummed paper stamps available from most post offices do the job, too, due to the gum affixed on their back. If you want to protect your M8 this way, I have a set of codes handy that you can write on the outside of the wrapped M8 before having it placed in the protective box, which is also available for your convenience at the nearest post office.

Philipp
 
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