dead pixel question?

[jaclblue]

A friend told me that it is common for all digital cameras to have dead pixels... is this true? I shoot with a 10d so I called canon and they told me almost the same thing. They also told me that if I wanted I could send in my camera and they would try to repair my dead pixels??? (after testing I have a dead pixel) Are finding dead pixels like finding a grey hair on your scalp if you try to remove it 5 more pop up??? What is normal as far as how many dead pixels ??? any information here would be appreciated

Thanks,
Jeff

 

[critter1]

Dead pixels and/or stuck, or hot pixels are absolutely normal.

If you go and buy an LCD monitor today, the usual answer is that the monitor can have up to 7 bad pixels before an exchange will be accepted.

Sometimes a single bad pixel will be objectionable.

Often, you have to look hard to find them. It depends.

I don't know, but from previous posts on this subject, most believe that bad pixels can be mapped out by Canon. Some don't agree.

One acid test is to take a 60 second exposure at high ISO with the lens cap on. Then view the result, but this is only for the brave and tolerant.

For the weak, ignorance is bliss.

 

[bethrouns]

http://www.starzen.com/imaging/deadpixeltest.htm

-Beth
(gear listed in profile)



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[Leonard Leffand]

Dead pixels are acceptable for displays but not for digital camera sensors in a professional grade camera. I own two 10D's and recently one of them (3 months old) developed 2 dead pixels. They were blazingly clear in a dance recital I shot. I had to manually correct about 200 images. The good thing is that you can clone stamp them into oblivion, the bad thing is that it is a real pain in the rear to do so.

I took my 10D into the local camera store where I bought it and it was sent to Canon for repair. It has only been a week so I do not have it back yet, but at first they wanted $144 to replace the sensor not realizing it was still under warranty. The proper paperwork was sent and it is being repaired.

Also you cannot repair a bad pixel or two on a sensor, the entire thing must be replaced which involves opening up the camera which could expose yu to a host of other issues once they put the thing back together.

Hopefully, they will fully test it prior to returning it to me.

Back to my original comment, on a display there is an acceptable number of dead pixels that must be tolerated, but on a professional quality DSLR it is absolutely unacceptable and do not let anyone tell you otherwise!!!

Lenny

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[Stordal]

I agree 100% with Leonard Leffand. As long as the dead pixel is on the CMOS (in other words, showing up on all your pictures) and not only the LCD (which doesn't affect the picture quality), this is totally unacceptable. I also had a dead pixel problem on my 10D, and brought it in to Canon (still under warranty). They immediately apologized, and told me that they would exchange the CMOS sensor. They also told me that they have a very strict quality policy on these higher end cameras, so that's why they don't just map out bad pixels, they simply exchange the whole sensor.

Hopefully I will have mine back at the end of the week. And, like Leonard Leffand, I hope they test it before they send it back... I'll get really frustrated if it comes back with another dead pixel, or dust on the sensor or something. Living without the 10D for 2 weeks is hard enough!

Dead pixels are acceptable for displays but not for digital camera
sensors in a professional grade camera. I own two 10D's and
recently one of them (3 months old) developed 2 dead pixels. They
were blazingly clear in a dance recital I shot. I had to manually
correct about 200 images. The good thing is that you can clone
stamp them into oblivion, the bad thing is that it is a real pain
in the rear to do so.

I took my 10D into the local camera store where I bought it and it
was sent to Canon for repair. It has only been a week so I do not
have it back yet, but at first they wanted $144 to replace the
sensor not realizing it was still under warranty. The proper
paperwork was sent and it is being repaired.

Also you cannot repair a bad pixel or two on a sensor, the entire
thing must be replaced which involves opening up the camera which
could expose yu to a host of other issues once they put the thing
back together.

Hopefully, they will fully test it prior to returning it to me.

Back to my original comment, on a display there is an acceptable
number of dead pixels that must be tolerated, but on a professional
quality DSLR it is absolutely unacceptable and do not let anyone
tell you otherwise!!!

Lenny

--

 

[Alekhine]

Hopefully I will have mine back at the end of the week. And, like
Leonard Leffand, I hope they test it before they send it back...
I'll get really frustrated if it comes back with another dead
pixel, or dust on the sensor or something. Living without the 10D
for 2 weeks is hard enough!

Dead pixels are acceptable for displays but not for digital camera
sensors in a professional grade camera. I own two 10D's and
recently one of them (3 months old) developed 2 dead pixels. They
were blazingly clear in a dance recital I shot. I had to manually
correct about 200 images. The good thing is that you can clone
stamp them into oblivion, the bad thing is that it is a real pain
in the rear to do so.

I took my 10D into the local camera store where I bought it and it
was sent to Canon for repair. It has only been a week so I do not
have it back yet, but at first they wanted $144 to replace the
sensor not realizing it was still under warranty. The proper
paperwork was sent and it is being repaired.

Also you cannot repair a bad pixel or two on a sensor, the entire
thing must be replaced which involves opening up the camera which
could expose yu to a host of other issues once they put the thing
back together.

Hopefully, they will fully test it prior to returning it to me.

Back to my original comment, on a display there is an acceptable
number of dead pixels that must be tolerated, but on a professional
quality DSLR it is absolutely unacceptable and do not let anyone
tell you otherwise!!!

Lenny

--

I also agree 100% with both you and LL.

My 10D also seems to have just ONE dead pixel, but im not sure im going to sent it back to canon for the replacing of the sensor for many reasons: first, i dunno if they're going to really replace the sensor or just try to map the bad pixel * second * I myself like some other friends have had a bad experience about sending back products still under warranty, in my case, i had been waiting long time to get back a product and then i realized that they just sent it back exectly the way i sent it to them!!

Another reason would be - I think the camera will be sent to some authorized center and how can i know that my camera is going into some expert's hands?, in my case i would want to go personally to Rome (i am italian) to follow the operation because I dont trust in the warranty policy, nobody works for you for free!

well and even if they are going to replace the sensor, it could have the same issue, not to talk about other problems like dust or smth else!

So the dilemma is, am i sending it back since i ALSO believe ONE dead pixel is UNACCEPTABLE or maybe I'd better leave my camera the way it is since i wouldnt know what's gonna happen?
thank you in advance for any advice..

Regards
Guido Tramontano

 

[RF Cat]

http://www.starzen.com/imaging/deadpixeltest.htm

-Beth
(gear listed in profile)



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Ian the RF Cat - wrote:-

Please provide some advice on hot pixels. I have run the test and found what I would call hot, I set the threshold to 80 got 2 in mid 80s and 1 at 100. There are no dead pixels reported. I also found my LCD monitor has a hot red or green pixel smack in the middle of my review screen. Why red/green, well in C1 it is green, but under the test software it is red. Only a problem on black or single colour displays.

The reported ones don't appear to affect the 10D pictures from what I can see. I will be printing some A4 rather than the 4 to a page I have been doing of late, then I will have more detailed look.
Also needing reading glasses will probably hide them anyway.

thank you Ian M

still learning
LOVE MY 10D
need to learn to check spelling and how to type!
http://www.pbase.com/ianm_au
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[JoachimT]

Hi,

I dont think that you should be paranoid about dead pixels. If you dont see any, dont waste your time searching for some. Because you might/will find some on long exposure with high ISO. then you will not be able to live with those even though you are not doing this kind of photography (such as night shots etc...) Plus, it is not because you dont have any dead pixels now, that you wont have any in the future.

3 months after I bought my 10D, I noticed a dead pixel. I take a lot of night shots, and it was there all the time. I compared with the shots that i took when I first got my camera and that pixel was not there.

I contacted Canon and they told me to send the camera to Irvine, CA. They returned it after 10 business Days (roughly 3 weeks if you add up the shipping time). I was happy until i tested the camera. The report said that they mapped out the dead pixel, but It was still there.

I called them again, and they told me to return it again with more proof, so I burnt a CD, printed some shots and sent it again. 3 weeks later, I got it back. Unfortunatly, the story was the same. The report said fixed, but the camera wasn't.

I was furious, this time Canon sent Fedex to my place to pick the camera up. 3 weeks later they returned it. The report said CMOS changed. It was indeed changed. And since then I did not see any dead pixel... yet. I would not be surprised that in 2000+ shots, one of those stuck pixel will show up.

I would say that if you can live with the dead pixel that you have, dont waste your time sending your camera to Canon. The time that my camera was at canon center was totaly wasted and knowing how fast the price of this kind of camera is dropping, you should not waste a second not using it.

I hope that my story helps... sorry for such a long post
Joach!m

 

[mats jonsson99386]

...Back to my original comment, on a display there is an acceptable
number of dead pixels that must be tolerated, but on a professional
quality DSLR it is absolutely unacceptable and do not let anyone
tell you otherwise!!!

Lenny

I assume you also always return enlargements with one or more single small dust spots?

 

[Leonard Leffand]

If there is a visible abnormality to a print whether it is in the printing or imaging process it is not acceptable and must be corrected. Wuld you deliver a print to a customer with a visible spot on the print from dust or any other source? My customers pay top $$ and have every right to expect perfection.

--

 

[Leonard Leffand]

I fully agree that if you can't see it in most pictures then it is a minor inconvenience to clone it out. The problem is that I shoot performing arts and on one particulair shoot I had to fix over 200 images for 2 bad pixels, to me that is a problem.

Lenny

--

 

[critter1]

I certainly agree with those that finding any significant imperfection with a two or three thousand dollar camera is unhappy and undesirable. I "expect" perfection too.

On the other hand, is it gonna happen? Does it happen? How frequently?

I don't know the answer to those questions, but from what I've read here over the past few years, hot, stuck and dead pixels are more normal than not.

If 9 out of 10 cameras were perfect, then having the 1 in 10 would be unacceptable to me too.

If 9 out of 10 cameras are "imperfect", then finding the elusive 1 in 10 would be an unpleasant experience, except in the successful end.

So, every individual has to judge his camera in his hands for himself whether it is "acceptable" or not.

If anyone knows the statistics of perfect vs imperfect sensors, then that would be useful information to share here.

 

[bob201044]

Due to the current manufacturing process, a sensor free of imperfections will cost MANY times the current cost of the 10D. Silicon wafers are extremely expensive and are not absolutely perfect. An acceptable level of imperfection has to be allowed or it would not be possible to have the digital cameras we now enjoy.

If you have an objectionable pixel that shows up clearly in your images then you should consider returning it for adjustment/repair. Otherwise, a small number of hot/dead pixels is normal and a practical constraint in the manufacturing process. Maybe one day the process will allow for noise-less, 20MP perfect sensors...but that day is not in the very near future.

Hope that helped
Omarlyn

 

[Leonard Leffand]

do not think that I am being too critical here. I do not believe there are significant focus issues with the 10D, while it may not focus as accurately as my Nikon F5 it is fine. But dead pixels that are consistenly noticable on your images is not a grey area, this is simply not acceptable, especially in a pro class model.

I certainly agree with those that finding any significant
imperfection with a two or three thousand dollar camera is unhappy
and undesirable. I "expect" perfection too.

On the other hand, is it gonna happen? Does it happen? How
frequently?

I don't know the answer to those questions, but from what I've read
here over the past few years, hot, stuck and dead pixels are more
normal than not.

If 9 out of 10 cameras were perfect, then having the 1 in 10 would
be unacceptable to me too.

If 9 out of 10 cameras are "imperfect", then finding the elusive 1
in 10 would be an unpleasant experience, except in the successful
end.

So, every individual has to judge his camera in his hands for
himself whether it is "acceptable" or not.

If anyone knows the statistics of perfect vs imperfect sensors,
then that would be useful information to share here.

--

 

[Leonard Leffand]

Any 20MP sensor will cost yo big $$$$. part of the process of bringing a product to market is the ability to manufacture consistent high quality components. That is why today's SLR's are 6MP and not 20MP, can they build it, sure, is here a high defect rate, sure, that helps to drive up the cost of the higher MP models. The reality is of course there will be defecitve 6MP sensors in the manufacturing process but they are screened out in the QA process. The 6MP sensor you get in your new 10D should be free of any defects.

Due to the current manufacturing process, a sensor free of
imperfections will cost MANY times the current cost of the 10D.
Silicon wafers are extremely expensive and are not absolutely
perfect. An acceptable level of imperfection has to be allowed or
it would not be possible to have the digital cameras we now enjoy.

If you have an objectionable pixel that shows up clearly in your
images then you should consider returning it for adjustment/repair.
Otherwise, a small number of hot/dead pixels is normal and a
practical constraint in the manufacturing process. Maybe one day
the process will allow for noise-less, 20MP perfect sensors...but
that day is not in the very near future.

Hope that helped
Omarlyn

--

 

[critter1]

I could be wrong, but I think the original poster was asking whether or not he should start a life long campaign to have a perfect sensor in his hands.

Misery loves company, and he has lots of company I think.

Even those that are saying that less than perfect is unacceptable to them, all seem to be suggesting that it has eluded them so far.

For the original poster, it also depends on whether he is talking dead vs hot vs stuck, and where on the sensor is the bad pixel, and whether if "ruins" every picture for him.

Should he "expect" to find a perfect sensor? I doubt it. Should he "want" a perfect sensor? Absolutely. Should he try to get a perfect sensor? That's his personal choice on how much time and misery he wants to invest.

If it is true that a couple of phone calls will lead to success, then absolutely he should do this.

 

[critter1]

It all depends on what the production yield is for a perfect 6MP sensor.
What if it was only 1%? I have no idea what the real numbers are.

Perhaps Canon should sort the sensors into groups based on the 100% testing that they are doing anyway, instead of having a pass/fail.

Perfect sensors would be one price.
1 imperfection is a smaller price.
4 imperfections is yet a smaller price, etc.

Then the market would determine what is "acceptable" and "unacceptable".

That's how many electronics are produced anyway for many years. Sorted and priced according to 100% testing.

Due to the current manufacturing process, a sensor free of
imperfections will cost MANY times the current cost of the 10D.
Silicon wafers are extremely expensive and are not absolutely
perfect. An acceptable level of imperfection has to be allowed or
it would not be possible to have the digital cameras we now enjoy.

If you have an objectionable pixel that shows up clearly in your
images then you should consider returning it for adjustment/repair.
Otherwise, a small number of hot/dead pixels is normal and a
practical constraint in the manufacturing process. Maybe one day
the process will allow for noise-less, 20MP perfect sensors...but
that day is not in the very near future.

Hope that helped
Omarlyn

--

 

[jaclblue]

First I have to say THANK YOU all of your posts are great and it gives me some perspective and knowledge into something I didnt know much about.

After further review/research I have found that my camera doesnt have a dead pixel or any hot pixels for that matter. I agree with all of you that looking for a dead pixel is a frivilous process. It was this frivilous process that caused me to think that I did have a dead pixel. The bottom line is; if you can't see it on an image then dont worry about it.

here are some great links that I found to be EXTREMELY helpful I hope you find them as helpful as I did.

Thanks
Jeff

http://www.steves-digicams.com/olympus_apm.doc

http://www.photo.net/bboard/q-and-a-fetch-msg?msg_id=006URA

A friend told me that it is common for all digital cameras to have
dead pixels... is this true? I shoot with a 10d so I called canon
and they told me almost the same thing. They also told me that if I
wanted I could send in my camera and they would try to repair my
dead pixels??? (after testing I have a dead pixel) Are finding
dead pixels like finding a grey hair on your scalp if you try to
remove it 5 more pop up??? What is normal as far as how many dead
pixels ??? any information here would be appreciated

Thanks,
Jeff

 

[Glen Elliott]

The one thing you could do is create an action for each orientation (landscape and portrait) and clone out the pixel manually. Once the action is recorded you can batch process all your pics. That is...if photoshop recognizes the clone stamp tool during action recording.

I fully agree that if you can't see it in most pictures then it is
a minor inconvenience to clone it out. The problem is that I shoot
performing arts and on one particulair shoot I had to fix over 200
images for 2 bad pixels, to me that is a problem.

Lenny

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