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Light Damaged Sensor Risk?


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#1 Macks Fiiod

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Posted 19 August 2016 - 11:47 PM

I've heard bits and pieces on how one shouldn't blast a light directly into a digital camera (or maybe only DSLR?) to avoid damage to the sensor.

 

How much light is required to actually screw it up permanently?

 

lens-flares.png

 

I ask because that technical warning seems to have been thrown out the window on countless music video shoots with wide open apertures and work lights/sunlight blasting lens flares right into the sensor. Are they slapping on thick ND filters and boosting the brights back on in post to save the sensor's health?

 

Been stuck on this one for a while.

 

Thanks.


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#2 Dom Jaeger

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Posted 20 August 2016 - 12:57 AM

I think it's more of a potential risk shining strong lasers onto a sensor, or shooting directly into the sun for an extended period. I've never heard of problems with normal lighting like you'd find at a concert or something.

Arri recommend not shooting directly into the sun but obviously lots of people do. I imagine it depends on how long you keep a focussed image of the sun in one spot on the sensor, and whether you use filtration. I've seen a black (actually purple) sun effect on Alexa footage which can happen if the sensor is overexposed by 8 or more stops past clipping (an effect common to CMOS cameras apparently) but it didn't damage the Alexa sensor.
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#3 David Mullen ASC

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Posted 20 August 2016 - 01:21 AM

I wouldn't worry about it, other than lasers, which can burn a spot in the sensor.  I certainly pointed into a lot of stage spots doing musical numbers for "Smash"...


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#4 Robin R Probyn

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Posted 20 August 2016 - 03:01 AM

Yes lasers are the one to worry about from what I know.. quite often used at concerts.. and unavoidable not to be strafed by the damn things sometimes..but its only for a second or less..

 

Ive had my camera over 2 years with plenty of direct sun and lights.. not for hours on end of course.. but without problems..its just off axis lights can sometimes give you grief with purple artifacts .. grid patterns etc..

 

More of a worry is OLED EVF,s.. these don't like direct light at all.. but usually have some sort of Auto shutdown/white out mode..


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#5 aapo lettinen

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Posted 20 August 2016 - 08:28 AM

With sun it is normally more of a temperature risk, with lasers you can get so much overvoltage to the photosites that is destroys the insulations between them. CDs in the microwave type of effect in the micro scale. Maybe you could get lots of over voltage also with the sun in some situations but it is much more unlikely than with lasers where there is no upper limit for point intensity and the intensities may be thousands of times higher than with sun
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#6 Macks Fiiod

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Posted 20 August 2016 - 12:08 PM

Videos like these are cool


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#7 Keith Walters

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Posted 06 September 2016 - 06:14 AM

It's not easy to damage the silicon sensor itself with heat, since they're already  heated to hundreds of degrees in the manufacturing process to "anneal" the silicon after the multiple doping processes, and also to create a protective layer of silicon dioxide.

However what you can easily damage is the coloured polymers that make up the Bayer mask on single sensor cameras. That can produce a localized discoloration that would ruin the sensor for commercial use.

Three chip CCD and CMOS cameras are virtually indestructible because the dichroic filters they use are made of multiple thin layers of glass.


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#8 Bruce Greene

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Posted 06 September 2016 - 11:00 AM

I've shot some welding recently, with no visible damage to the Alexa.  There's no artificial light that can equal arc welding for brightness...

 

There were some strange artifacts recorded though :)


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