CCDs wear out?

mpmcleod

I read somewhere that the CCDs in DSLRs can wear out. Or more correctly their ability to capture light will become less effective over time, leading to dimmer picture and color that is not correct (or at least different than when the camera was new). This is because DSLR CCDs are very sensitive to light (vs. handheld camera which are constantly exposed to light).

One place I read was that after about 20,000 shots there was a measurable charge difference compared to shot 1.

Can someone tell me is this is true? I would appreciate an EEs jumping in here.

Any links out there with solid information? Anyone notice real-word difference between their brand new photos and photos after 20,000 shots?

thanks,

cmason

Where would the 'wear' come from? There are no moving parts or anything hitting it? Some cameras (Canon) use CMOS instead, btw.

mpmcleod

cmason wrote:

Where would the 'wear' come from? There are no moving parts or anything hitting it? Some cameras (Canon) use CMOS instead, btw.

(I am not an expert this is just my understanding. If there is a expert in this area I would love to hear you thoughts and increase my understanding).

I agree that it would be more likely for my shutter (moving part) to fail but if you think about your LCD monitor or TV you are probably aware that they fail and yet have no moving parts. Also computers memory, CPUs and motherboards fail with no moving parts. However that is failure, which is not exactly what I am wondering about.

All eletrical devices wear (very little) as electrons are displaced and replaced as electricity flows through them. More importantly, in regards to failure, the substrates that the devices are on and in can shift through heating/ cooling cycles, movement, etc.

In the case of a light capturing device, photons are hitting the device (an active force). Electricty is engaging the device to read the photons and measure their energy and wavelength (light intensity and color). The device is calibrated to covert these reading into digital information. Does this change over time?

I couldn't find anythin definitive on the web in casual browsing so I thought I would ask people here if they have noticed any change in their photos between when their camera was new and after 20-100,000 shots.

colourbox

You don't need moving parts to have wear. There aren't any moving parts in a memory card, but the cells in a memory card do have a finite number of reads and writes. It's just a number high enough that you'll get a decent lifetime out of the card.

Maybe someone had heard about the known wear characteristics of a memory card chip, and they confused it with the camera sensor chip?

Khaos

I think you answered your own question in that last post. Over time it is more likely the electronic components on the camera will fail before the actual sensor. I believe the sensor is silicon and will wear very well over time.

Flash cards use electron displacement. Odd number of electrons equal a 1 and an even number equal a 0 in binary code for storage, and yes over time the electrons energy ceases to exist and the card "dies"

I thought the sensor only captured the actual light being shown upon it and the camera is what did the conversion. I could be wrong.

ScottMcLeod

This is how i've been explained to by the Canon Techs:

The sensor doesn't wear out over time, what happens, is pixels individually start failing over time.

When you buy it, it probably has zero dead pixels that you know of (though there's probably a few mapped out...)

Every time the sensor gets charged and takes a picture, it does put wear on the sensor, but they don't get "less sensitive." They just kinda die out, slowly.

Moving parts will likely die before your CCD/CMOS dies though, at least on a DSLR.

Forehead

Which sensor lasts longer?
SO far, I know of only two sensors used in digital cameras--CCD and CMOS.

Which sensor can be expected to last longer, i.e., after 20,000 shots, which one will more likely have the quality of Shot #1?

Also, does sensor SIZE influence durability? Will the large-format sensors (with the larger pixel dimensions) last longer than the smaller sensors of the same pixel count?

flyingdutchie

Forehead wrote:

SO far, I know of only two sensors used in digital cameras--CCD and CMOS.

Which sensor can be expected to last longer, i.e., after 20,000 shots, which one will more likely have the quality of Shot #1?

Also, does sensor SIZE influence durability? Will the large-format sensors (with the larger pixel dimensions) last longer than the smaller sensors of the same pixel count?

There are 4 that i know of : CMOS, CCD, LBCAST and Foveon.

But don't worry about this. Don't choose a camera on a 'how long does a sensor last' question. The answers are 'very very long' and 'very very very long'.

Take, for example, point & shoot cameras. They are submitted to light all the time (previewing image in LCD and video options). These cameras funtion perfectly ok, even after years and years of use. Compared that to DSLRs, whose sensors are exposed to light only a fraction of a second each time a picture is taken.... Do the math

cwphotos

Dont forget the NMOS sensors in the Olympus DSLRs

Bob Bell

Forehead wrote:

SO far, I know of only two sensors used in digital cameras--CCD and CMOS.

Which sensor can be expected to last longer, i.e., after 20,000 shots, which one will more likely have the quality of Shot #1?

Also, does sensor SIZE influence durability? Will the large-format sensors (with the larger pixel dimensions) last longer than the smaller sensors of the same pixel count?

20,000 shots is very little for a dslr. For some people its a year and for some its 2-3 months or less. I know guys who have 150,000 on a body and they are still being published in SI or USA Today.

When a photo site gets burned out or gets hot. Send it to canon for mapping. No biggie. Blow a shutter curtain in the first year, Send it to canon for replacement. Shutter curtains are around @250 depending on camera.

I can see CCD's losing resolution abilities over years of use but that will not be a concern of mine. If I get 200,000 out of 1 body, you can't really complain, ya know

A lot more cameras are tossed on a shelve from the need to upgrade than from major failure. After all, DSLR technology is not a mature technology so the reason to uprade because of features will continue to dominate replacement reasons for a few more years I believe.

DoctorIt

Since this question has naturally evolved into a bit of how does CCD differ from CMOS - here's a link that I've bookmarked. One of the best articles to explain the difference between the two imagers:

http://www.kodak.com/US/en/corp/researchDevelopment/technologyFeatures/cmos.shtml

If anyone has good technical info on the "other" types of chips, please post them! For example, I know my D2H has an LBCAST chip, but from the little I've read, its very similar to CMOS architecture, but with some pep added in so it can handle the machine gun speed.

Bob Bell

thats a good link Dr IT.

Here is another one along those lines: http://www.dalsa.com/markets/ccd_vs_cmos.asp

There was a really nice Foveon article probably a year ago that I am going to look for.

gtc

shutter
the most usual part to wear out in a dslr is the shutter and perhaps the mirror lift mechanism

Cloudkicker

So after it wears out the camera is no good? Or can you get it fixed?

Forehead

I knew a Bob Bell in Camp Verde.

You're not the same guy, are you

Bob Bell wrote:

thats a good link Dr IT.

Here is another one along those lines: http://www.dalsa.com/markets/ccd_vs_cmos.asp

There was a really nice Foveon article probably a year ago that I am going to look for.

Forehead

The camera can be sent in and have things replaced--like the sensor.

There comes a point, though, where you're better off just getting a new camera!

Cloudkicker wrote:

So after it wears out the camera is no good? Or can you get it fixed?

Bob Bell

Forehead wrote:

I knew a Bob Bell in Camp Verde.

You're not the same guy, are you

I don't thinK i've ever been to Camp Verde. Was the one you knew from Chicago and about 6'6, played basketball at D1 school? I am also 38 now.

Forehead

I read last night where one of the really big pluses of CMOS over CCD is how much less power they use.

That's right, right?:D

DoctorIt wrote:

Since this question has naturally evolved into a bit of how does CCD differ from CMOS - here's a link that I've bookmarked. One of the best articles to explain the difference between the two imagers:

http://www.kodak.com/US/en/corp/researchDevelopment/technologyFeatures/cmos.shtml

If anyone has good technical info on the "other" types of chips, please post them! For example, I know my D2H has an LBCAST chip, but from the little I've read, its very similar to CMOS architecture, but with some pep added in so it can handle the machine gun speed.

Forehead

Alas, no got a dslr, just a wimpy Nikon E5400. That little sensor is what, maybe the size of the average little fingernail?

On another note, as many of my shots are in industrial settings, I want them to be PRIMO. But I also can't fumble with camera bodies and extra lenses, nor can I worry about dust getting onto mirrors and sensors.

For industrial equipment/physical plant applications, I've been strongly considering the Sony Cybershot DSC-R1. It doesn't have a lot of bells and whistles (like my Nikon), but that Zeiss lens and 10.2 MP CMOS sensor of "12 times" the size of the one I have--sounds like a sweet combo. And I just gotta have a swivelling monitor for those shots that even an 8-year-old contortionist might otherwise have trouble with!

What's your opinion? Heck, what's ANYONE'S opinion on that Sony?

Bob Bell wrote:

20,000 shots is very little for a dslr. For some people its a year and for some its 2-3 months or less. I know guys who have 150,000 on a body and they are still being published in SI or USA Today.

When a photo site gets burned out or gets hot. Send it to canon for mapping. No biggie. Blow a shutter curtain in the first year, Send it to canon for replacement. Shutter curtains are around @250 depending on camera.

I can see CCD's losing resolution abilities over years of use but that will not be a concern of mine. If I get 200,000 out of 1 body, you can't really complain, ya know

A lot more cameras are tossed on a shelve from the need to upgrade than from major failure. After all, DSLR technology is not a mature technology so the reason to uprade because of features will continue to dominate replacement reasons for a few more years I believe.

Bob Bell

Forehead wrote:

Alas, no got a dslr, just a wimpy Nikon E5400. That little sensor is what, maybe the size of the average little fingernail?

On another note, as many of my shots are in industrial settings, I want them to be PRIMO. But I also can't fumble with camera bodies and extra lenses, nor can I worry about dust getting onto mirrors and sensors.

For industrial equipment/physical plant applications, I've been strongly considering the Sony Cybershot DSC-R1. It doesn't have a lot of bells and whistles (like my Nikon), but that Zeiss lens and 10.2 MP CMOS sensor of "12 times" the size of the one I have--sounds like a sweet combo. And I just gotta have a swivelling monitor for those shots that even an 8-year-old contortionist might otherwise have trouble with!

What's your opinion? Heck, what's ANYONE'S opinion on that Sony?

I personally think its a crazy point and shoot. The LCD thing is weird, having a hot shoe off axis is strange. I think the panasonic Lumix with 10x optical zoom, leica glass, image stabilization might still be the leader in L shaped digicams. For a grand, you should be able to change out lenses. I often use 20mm to 400mm, something that digicams wont offer. Just my 2 cents

Forehead

Yes, the limited zoom (120mm?!) can cramp one's shooting style.

Image stabilization: how does it work? Does it really work that well? After a couple of Starbucks Ventis, coffee nerves could well ruin some once-in-a lifetime/one-in-a million photo ops!

Maybe I should wait until after the Sony Borg Cube assimilates Konica-Minolta.

Bob Bell wrote:

I personally think its a crazy point and shoot. The LCD thing is weird, having a hot shoe off axis is strange. I think the panasonic Lumix with 10x optical zoom, leica glass, image stabilization might still be the leader in L shaped digicams. For a grand, you should be able to change out lenses. I often use 20mm to 400mm, something that digicams wont offer. Just my 2 cents

jimf

Forehead wrote:

Image stabilization: how does it work? Does it really work that well?

There are at least three kinds of image stabilization in common use. DSLR lenses ("IS", "VR") have an element that is moved to counter vibration picked up by motion sensors in the lens. Some DSLR bodies (Minolta? Fuji? I forget) and some P&S cameras use a mechanism that moves the sensor instead. Lastly it is possible to stabilize "electronically", analyzing a frame sequence to determine motion and attempt to correct for it.

All of these techniques work. The mechanical stabilizers, when well implemented, work extremely well. Using the Canon 70-200 f/2.8 IS L I have managed to pull out usable shots when hand-held full-zoom at 1/80th, which I consider pretty remarkable. But even the electronic stabilizer on my Olympus 720sw makes a substantial difference.

flyingdutchie

jimf wrote:

There are at least three kinds of image stabilization in common use. DSLR lenses ("IS", "VR") have an element that is moved to counter vibration picked up by motion sensors in the lens. Some DSLR bodies (Minolta? Fuji? I forget) and some P&S cameras use a mechanism that moves the sensor instead. Lastly it is possible to stabilize "electronically", analyzing a frame sequence to determine motion and attempt to correct for it.

All of these techniques work. The mechanical stabilizers, when well implemented, work extremely well. Using the Canon 70-200 f/2.8 IS L I have managed to pull out usable shots when hand-held full-zoom at 1/80th, which I consider pretty remarkable. But even the electronic stabilizer on my Olympus 720sw makes a substantial difference.

I second that.
VR/IS on lenses works very very well for reducing camera shake.
I shot this picture hand-held at 82mm focal-length, f/2.8 and 1/13th of a second (lens used 70-200mm f/2.8 VR):


-- Anton.

ian408

Electronic wear is somewhat different than mechanical wear. In the case of
a camera shutter, movement of the shutter causes wear. In chips it is the
charge/discharge cycle, manufacturing defects, rough handling, exposure to
the elements, static discharge and a number of other causes. Most of which
you'd need an electron uScope to see.

If you think about how chips are manufactured, there are many things that
can go wrong. The wires between the silicon and packaging can break
over time (inside the chip packaging), the manufacturing processes continuously
change--constant efforts to get more in less space can also have unpredictable
results.

Maybe electronic wear isn't as visible but it still happens. And as someone
else said, you'll probably be sending the camera in for something mechanical
well before you send it in for a new sensor (in most cases and presuming
you've not scratched the filters).

Ian

Forehead

Well, I guess I should look for this feature for my next camera purchase!

jimf wrote:

There are at least three kinds of image stabilization in common use. DSLR lenses ("IS", "VR") have an element that is moved to counter vibration picked up by motion sensors in the lens. Some DSLR bodies (Minolta? Fuji? I forget) and some P&S cameras use a mechanism that moves the sensor instead. Lastly it is possible to stabilize "electronically", analyzing a frame sequence to determine motion and attempt to correct for it.

All of these techniques work. The mechanical stabilizers, when well implemented, work extremely well. Using the Canon 70-200 f/2.8 IS L I have managed to pull out usable shots when hand-held full-zoom at 1/80th, which I consider pretty remarkable. But even the electronic stabilizer on my Olympus 720sw makes a substantial difference.