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FrozenGate by Avery

Concert Laser kills dSLR sensor






I didn't think this was sensor burn, (in the traditional meaning), because the camera is hit several times and only once the damage showed, and in white? I believe this more since reading this post below the videos...

"alienshards 07/26/10

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I doubt the pixels themselves are actually damaged. More likely it's the readout circuitry.

As light is shown on the sensor, each pixel acts like a bucket and stores electrons that are generated by photon strikes.

Then, each bucket is effectively "moved" (by changing conductance of certain sections of the material in a certain order) into a set of masked pixels; these cannot absorb photos. Each sensing pixel has a masked pixel right below it.

the store electrons (and thus the information) is then moved, again by manipulating the semiconductance of the chip), so that each pixel's data can be read individually. This results in a flow of electricity, and thus a current.

If all the pixels on a row are filled completely with electrons, and then read out, this results in a higher than normal current flowing through the readout circuit. I believe it is this that is actually damaged.

This also explains why only one line is damaged- it must line up exactly. "


I still don't think I'll show this video to my Dad though. Just in case I ever want to borrow his 5D!

M
:)
 
heres a pic of a white wall using my laser camerea

DSCN3816-1.jpg


i have a dslr just for laser photos and a dslr for every day use.
 
That wall needs painting Andy. Just look at all those marks! :crackup:

M
:)
 
Aren't display lasers required to be metered 5mW or below when doing crowd scans? Or is that just me dreaming?
 
^ thats you dreaming :p Lasers used at big concerts and such can be several hundered mW's in power
 
Woodofcville said:
Aren't display lasers required to be metered 5mW or below when doing crowd scans? Or is that just me dreaming?
Click to expand...

If my goldfish-esque memory can work, according to the ILDA crowd scanning document, the MPE for crowd scanning is something like 10mW/cm^2. It's also usually ignored. The power can be cranked up for when it's above eye level, but it's supposed to be low for crowd scanning, so the blink/aversion reflexes can kick in fast enough.
 
Woodofcville said:
Aren't display lasers required to be metered 5mW or below when doing crowd scans? Or is that just me dreaming?
Click to expand...

in the US yes... but the flood of powerful lasers coming in from china has brought the price down to the point that anyone can hop on ebay and buy a projector that puts out serious power without knowing any of the dangers of said projector...

or it could have been in europe where they go by MPE exposure limits, and even then, usually exceed them either unknowingly or just because they don't really care I guess
 
That is European audience scanning, and they like 10x the MPE power. The argument is that statistics show that when done properly, the risk of 10X MPE is low. Key word here is "properly" with calculations, measurements,controlled distances, and pre show quality control checks. some of which are NOT seen in that video.

In other words don't try "audience scanning" unless you go to a ILDA conference or consult some folks on PL or Laserfreak and learn how.

Why I really posted is a warning. If you think CMOS sensors pop easily in high end cameras, wait till you meet some one who hits a high end DMD projector with a laser. They really hope their insurance is current. The DMD chips pop even easier then the CMOS ones. So if your doing a rave miss the Barco with the beams, or be prepared to pay "BIGBUCKS" for the repair. This has been seen with the high end, big lens, professional models.

ref: http://www.laserist.org/forums/showthread.php?t=156

When I worked at the university, one of my students aimed a 5-6 mW hene into a VIDICON based camera via a F2.2 video lens. (That is a tube folks, the glass thing used before CCDs) When he noticed it burned the sensor, he carved his initials into the vidicon before he brought it to me for repair (GRUMBLE!) There is a huge installed base of vidicon security cameras left over from the 80s and 90s.

Steve
 
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