How much light NMOS sensor can take before damaged

[splim]

You may not doing it, but if...

someone borrowed your cam(those with live view),
went to beach to take sunset,
mount on tripod,
turn on live view to frame, because the eye can't take the light from the sun from viewfinder ....



What I want to know is, how safe is it, eg. like doing HDR that require a longer expose for shadow with the afternoon sun in frame, without using any ND filter ? (not using live view here)

[headfonz]

not a good idea...you may 'burn' your sensor just like how our eyes get burnt by staring directly in the sun with or without shades. the manual has something on this.

[tomcat]

Originally Posted by splim You may not doing it, but if... someone borrowed your cam(those with live view), went to beach to take sunset, mount on tripod, turn on live view to frame, because the eye can't take the light from the sun from viewfinder .... What I want to know is, how safe is it, eg. like doing HDR that require a longer expose for shadow with the afternoon sun in frame, without using any ND filter ? (not using live view here)

You would need to assure yourself first as to whether the person you are lending the camera to actually have any basic knowledge on photography or not before you let him have your camera.

Long, long before you could damage your sensor through over-exposure (even without using Live View), the image would have been overblown to the extent that the image is completely white and completely white images are useless for HDR purposes. So there's no need to subject the camera to that level of overexposure in the first place if the user has some basic knowledge of photography.

If it is just turning on the Live View to frame a sunset shot, and then turning off after that's done, that's just normal usage and can't possibly damage the sensor.

[srinivasanj]

Strange coincidence that my friend and I were discussing this exact same issue this morning.

Exposure for sunrise/set can also be controlled by aperture isnt? Since the 'image' is so bright, wouldnt adjusting aperture be a better option maintaining shutter constant? The usual method of shooting HDRs is to keep aperture constant though, to get keep the DOF constant I would assume.

So what is the best way to shoot sun-related shots without damaging the sensor?

[Zoobiee]

Originally Posted by srinivasanj So what is the best way to shoot sun-related shots without damaging the sensor?

Maybe ND filters?

[OlyFlyer]

Come on guys, people have been taking images of sunset sunrise ever since cameras got invented. That is the most photographed scenery in the world. I never heard of burned out sensors or burned out eyes. I think you are overly careful, but I would not use LV for that, the VF is much better and there is absolutely no way you damage your eyes or the camera that way. Of course, stareing for a long time is different, but even that, at sunset or sunrise, I doubt it can do any damage. You will close your eyes and give up long before.

As for lending the camera to a friend, I would say no. I would never lend my camera basically to anyone, but definitely never to one not already have a dSLR of some brand, which in that case would be pointless for this occasion. I think the risks are more in the lending than in taking a few sunset photo, even with LV.

[srinivasanj]

Good point there. Just wondering if the sensor starts ageing over time due to frequent over exposures.

Does any body know if the sensor ages normally, like humans I mean...function of time?

[headfonz]

Agree with Olyflyer's points on not using LV for framing shots with the sun in frame.

my earlier response was more concerned with this line

like doing HDR that require a longer expose for shadow with the afternoon sun in frame, without using any ND filter ?

maybe i misunderstood the TS's question as "shooting a long exposure of the afternoon sun" instead of the intended meaning of sunset.

what i was trying to say is that i don't think its a good idea expose the sensor directly at the sun at between 12pm - 5pm here in SG, and i won't try it even with the aperture closed down to f16 - f22

[OlyFlyer]

Originally Posted by srinivasanj Good point there. Just wondering if the sensor starts ageing over time due to frequent over exposures. Does any body know if the sensor ages normally, like humans I mean...function of time?

Overexposure is probably not a problem. It would be a problem if you concentrate the light to a point, like focus on the sun. Than, according to some people may burn your sensor. I am not sure they are right but it is better to be careful with the midday sun. Sunset and sundown shound not be a problem, definitely not for an image which is taken with a proper shutter speed and not overexposed. Why would you constantly overexpose? What is the point?

[Octarine]

Originally Posted by headfonz what i was trying to say is that i don't think its a good idea expose the sensor directly at the sun at between 12pm - 5pm here in SG, and i won't try it even with the aperture closed down to f16 - f22

Can you give a good explanation for this? All sensors (ok, except those with IR modification) have an IR filter and most people use UV filters at their lenses. So what's left? Ordinary light of the range we can see with normal eyes.
Secondly: when do you expose your sensor to the sunlight? Only after the mirror flipped up and the shutter is open. As long as you don't do something terrible stupid (Bulb exposure of 2min into direct sun) I don't see any issue here. Even half-automatic modes will limit the amount of light to a reasonable value.
So what do you think will damage your sensor then during an appropriate exposure for a normal picture? As OlyFlyer said: if there were anything dangerous in taking pictures of sunset or sunrise we would know already by the huge amount of burned sensors and spoiled cameras...

[egnaro]

will light like this damage my camera phone shooting sunset like this?

[drakon09]

Originally Posted by egnaro will light like this damage my camera phone shooting sunset like this?

Nope, don't worry.

[Gizmore]

Can you give a good explanation for this? All sensors (ok, except those with IR modification) have an IR filter and most people use UV filters at their lenses. So what's left? Ordinary light of the range we can see with normal eyes.
Secondly: when do you expose your sensor to the sunlight? Only after the mirror flipped up and the shutter is open. As long as you don't do something terrible stupid (Bulb exposure of 2min into direct sun) I don't see any issue here. Even half-automatic modes will limit the amount of light to a reasonable value.
So what do you think will damage your sensor then during an appropriate exposure for a normal picture? As OlyFlyer said: if there were anything dangerous in taking pictures of sunset or sunrise we would know already by the huge amount of burned sensors and spoiled cameras...


By looking at the EM spectrum, it's easy to deduce.



Point is that human eyes are only sensitive to a certain spectrum of light. From about 380nm to 770nm, which is pretty narrow.




The problem with electronic sensor is that it is sensitive to a a wider band of light.




The purpose of a camera is to capture an image and that image has to be similar to what our eyes perceived. Therefore, IR filters are inbuilt into cameras as electronic sensors are very sensitive to it. UV filters are not inbuilt into camera because the sensor sensitivity at UV wavelength is not as much as IR. And so, UV filters are not inbuilt.

[drakon09]

Actually it's not about the light frequency; it the strength of the emission i.e. intensity, that will hurt electronics.

Now, the idea that sunlight will damage the sensor probably came from people burning themselves while changing lenses; the lens catches sunlight, focuses the light onto a point, and then skin/clothes starts burning.

However, where cameras are concerned, there's little danger of that happening because the lens will cast a circle of light onto the sensor, not a concentrated point. At the same time, silicon can take extremely high temperatures without burning.

So when shooting into the sun, the last thing you should worry about is the camera, because your eyes will go first!

[headfonz]

Originally Posted by Octarine Can you give a good explanation for this?

sorry i am not technically competent enough to give you a good explanation

anways, this is a forum reply i read once that i got the idea from: http://forums.popphoto.com/rss/messa...essage.id=5390

Quote: The only way a sensor (CMOS or CCD) can be "burned" is by leaving it exposed directly to the sun for a long period of time. If you accidentally leave the shutter open while the camera is pointed at the sun, the heat generated (by the sun hitting the sensor, *not* by any electricity in the sensor) can melt the RGB filters (which are a thin membrane over the microlenses) and ruin the sensor's ability to take color images. Otherwise, there is no "burn out" from long exposures of any kind. None. Your sensor can quite easily do hours-long exposures with no effect to the sensor at all, as long as you're not pointing it at the sun. And long exposures don't cause any kind of heat from electricity to build up in the sensor -- the heat actually comes from the surrounding circuits, not from the sensor itself. And what the heat does is simply increase dark current (which shows up in images as "hot pixels"), it doesn't harm the sensor in any way.

interesting how this thread is turning out

[OlyFlyer]

Originally Posted by drakon09 Actually it's not about the light frequency; it the strength of the emission i.e. intensity, that will hurt electronics. Now, the idea that sunlight will damage the sensor probably came from people burning themselves while changing lenses; the lens catches sunlight, focuses the light onto a point, and then skin/clothes starts burning. However, where cameras are concerned, there's little danger of that happening because the lens will cast a circle of light onto the sensor, not a concentrated point. At the same time, silicon can take extremely high temperatures without burning. So when shooting into the sun, the last thing you should worry about is the camera, because your eyes will go first!

Well explained about where and how image is created. It is a common misunderstanding that the image is created in the focal point, which is not.



This is illustrated by the image above.

In fact, I doubt anybody ever burned himself or herself while changing lens. Even on the midday sun that takes quite a while and you really need to be extremely unlucky or very precise, because burning can only be done if you hold a lens in parallell with the sun's rays and hold something exactly in the focal point. Just try it with a piece of paper, you will also see it takes quite a while before anything happens even in Singapore, which is almost exactly on the equator, nearest the sun. Normally, when I change lens I never have my lenses without front cap when I start and it never takes more than 3-5 seconds before the rear cap is also on and the new lens is installed on the camera. I doubt that time is enough for any damage on anything, even under very unlucky conditions.

[dorts]

Quote: can melt the RGB filters (which are a thin membrane over the microlenses) and ruin the sensor's ability to take color images.

Not bad! Become black and white pictures.

[drakon09]

Originally Posted by OlyFlyer In fact, I doubt anybody ever burned himself or herself while changing lens. Even on the midday sun that takes quite a while and you really need to be extremely unlucky or very precise, because burning can only be done if you hold a lens in parallell with the sun's rays and hold something exactly in the focal point. Just try it with a piece of paper, you will also see it takes quite a while before anything happens even in Singapore, which is almost exactly on the equator, nearest the sun. Normally, when I change lens I never have my lenses without front cap when I start and it never takes more than 3-5 seconds before the rear cap is also on and the new lens is installed on the camera. I doubt that time is enough for any damage on anything, even under very unlucky conditions.

Spot on Flyer; I was quoting an urban myth, myself I haven't seen any lens accidents yet!

[splim]

Many reply but... never mind..

Found something here
http://panasonic.co.jp/corp/news/off...n070514-2.html

There is one paragraph in it:
"Conventional MOS image sensors require polymer onchip microlenses and dyed RGB color filters, which are fragile and extremely susceptible to sunlight exposure and a change in temperature. As a result, color images captured by a camera used under direct sunlight, including the ultra-violet (UV) portion, and higher temperature conditions will fade faster."...

Sounds like it will eventually cause color fading if it's a conventional type

[tomcat]

Originally Posted by splim Many reply but... never mind.. Found something here http://panasonic.co.jp/corp/news/off...n070514-2.html There is one paragraph in it: "Conventional MOS image sensors require polymer onchip microlenses and dyed RGB color filters, which are fragile and extremely susceptible to sunlight exposure and a change in temperature. As a result, color images captured by a camera used under direct sunlight, including the ultra-violet (UV) portion, and higher temperature conditions will fade faster."... Sounds like it will eventually cause color fading if it's a conventional type

You do realise that this is a sales pitch by Panasonic for their NMOS sensor? They are just saying that their NMOS sensor is different and better than conventional MOS sensors because.... "Conventional MOS image sensors require polymer onchip microlenses and dyed RGB color filters, which are fragile and extremely susceptible to sunlight exposure and a change in temperature. As a result, color images captured by a camera used under direct sunlight, including the ultra-violet (UV) portion, and higher temperature conditions will fade faster." ... but their NMOS sensors don't.

I'm sure that both Canon and Nikon will also have something different to say about the CMOS sensors that they are also using in their DSLRs.