Dead Pixel?

u8myufo

u8myufo

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Rich
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I have noticed this bright green dot on a few pictures when veiwing in the RAW stage, its in the same place each time. I take it its a dead pixel on my 50D, as it is only a few month old would you suggest taking it back from where I purchased it? or would you just live with it. Any advise would be great. I have taken a snapshot of the screen but when resized down for the forum you cant see it :bang::bang:
 
You pay all that money for it so you want it right. Yes it may be small but if you can get it replaced then do so. What are you losing?
 
Andy said:
You pay all that money for it so you want it right. Yes it may be small but if you can get it replaced then do so. What are you losing?
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He's not losing anything, but by insisting on better than 99.99999% quality he's helping to put up the prices for all of us.

Also - how much does it really matter? The OP has already said that at normal image sizes (ie not pixel peeping) it doesn't show up. In fact, if you print 10x8" at 300 DPI you're only using 7 megapixels, so one hot pixel still won't show up, even if you scrutinise the print with a magnifying glass.
 
Canon Bob said:
1 in 15 million ? I think I'd live with it.

Bob
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KayJay said:
If it's just the one I wouldn't worry about it. Does the 50D have noise reduction? That might help hide it? Although turning it on just to hide that pixel is probably overkill if not needed.

You should see the problem I had with my first 5dmk2 body.
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Andy said:
You pay all that money for it so you want it right. Yes it may be small but if you can get it replaced then do so. What are you losing?
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StewartR said:
He's not losing anything, but by insisting on better than 99.99999% quality he's helping to put up the prices for all of us.

Also - how much does it really matter? The OP has already said that at normal image sizes (ie not pixel peeping) it doesn't show up. In fact, if you print 10x8" at 300 DPI you're only using 7 megapixels, so one hot pixel still won't show up, even if you scrutinise the print with a magnifying glass.
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Thanks all for the comments, i have gone and done it now posting this up. There is obviously two schools of thought, and I have not decided what to do yet. Cant quite see your reasoning though Stewart to put the price of your goods up :thinking: Would you accept a new car with a small but noticeable chip in the paintwork? Or maybe an lcd with a dead pixel? :D
 
It must be bothering you otherwise you wouldnt be posting, take it back :)

Then of course theres the risk of canon putting the price on it by a few pounds because some random got a refund *Wink Wink*
 
I've got a couple of 50D's and I'm quite prepared to accept that Canon may have screwed up a pixel on each of them. I'll start to worry about it when I stop screwing up the other 14,999,999 pixels with the majority of shots I take :(

Bob
 
u8myufo said:
I have noticed this bright green dot on a few pictures when veiwing in the RAW stage, its in the same place each time. I take it its a dead pixel on my 50D, as it is only a few month old would you suggest taking it back from where I purchased it? or would you just live with it. Any advise would be great. I have taken a snapshot of the screen but when resized down for the forum you cant see it :bang::bang:
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Just visit any Canon service center (like Fixation) - and they will remap hot/dead pixels while you wait. I've done it with my Nikon a few times. Pity that camera manufacturers don't release a software for it or better yet make this option available in camera firmware...

FYI, Lightroom and ACR will remove/remap hot/dead pixels automatically so if you use them and shoot RAW those pixels should not matter really...
 
i think they will tell you where to go. Industry standard for lots of things is called "six sigma" (nothing to do with lenses - all started off with Motorola and later Toyota) - all based on standard deviations (one SD being a sigma)

Basically for a process to be 6 Sigma compliant must have no more than 3.4 defects per million operations or products or whatever.......... i.e. 99.999997% is OK.

Therefore one dead pixel out of 14.2 million? - live with it.


as to your point about a small chip on a new car - no, but can very easily be rectified by bodyshop prior to delivery.......... unless you plan on blowing up to a bloody huge size and print off (i.e. size of your wall) then not a problem, and even so, if just one pixel, a simple clone of the pixel next to it in Photoshop CS3/elements will rid you of the issue..............
 
This has came up before, I had a quick look but couldn't find the thread. But I'm sure you can remap them yourself, it had something to do with putting the camera into maual clean mode, then doing somethig else. I know that's not too helpful but maybe someone will rememeber the thread.
 
Just being curious I contacted the shop where I bought it, the guy explained that as I registered it with them at the time it would be under a 2yr warranty and offered to send it back to Canon to have it checked over. Now would Canon be so obliging to give it a quick hoover out before returning it? :lol::lol:
 
u8myufo said:
Now would Canon be so obliging to give it a quick hoover out before returning it? :lol::lol:
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Don't know about Canon themselves but AJ Johnstone (authorised Canon service centre) gave my SLR a spring-clean when I sent it in for a sensor clean under warranty. Got rid of some annoying hairs and dust bunnies on the focusing screen and mirror :)

A.
 
u8myufo said:
? Or maybe an lcd with a dead pixel? :D
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They are allowed 5 on a 19" before it is deemed faulty :thumbs:

1 dead pixel on a cameras image sensor is well within accepted industry tolerance, Nikon will map them out, which is basically turning it off and telling it to do what the one next to it records :) (That was my simplified summary).

I expect Canon would do the same, but to be honest I would not worry about it.
 
Hawker said:
This has came up before, I had a quick look but couldn't find the thread. But I'm sure you can remap them yourself, it had something to do with putting the camera into maual clean mode, then doing somethig else. I know that's not too helpful but maybe someone will rememeber the thread.
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I posted a similar thread to this a while back - here

There were some suggestions given. I decided to just accept them, as others have said a couple of pixels out of 15million or so - That's pretty good success in my book.

Do I notice them? Sometimes, so just use CS3 to heal or clone out.
 
Martyn... said:
They are allowed 5 on a 19" before it is deemed faulty :thumbs:

1 dead pixel on a cameras image sensor is well within accepted industry tolerance, Nikon will map them out, which is basically turning it off and telling it to do what the one next to it records :) (That was my simplified summary).

I expect Canon would do the same, but to be honest I would not worry about it.
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With LCDs monitors it is a little more complex than that.

There are several 'severity levels'
A dead pixel, i.e. one which never turns on, is a low severity
A hot pixel, one which always shows the same colour, is a higher severity.

Then there is a limit for how many high or low severity defects (scratches also count) within the whole frame.
Then after that, there is a minimum distance that two defects of a severity level can be within each other.

If it is reported to Canon and is not within these limits, they will change it. If they are within these limits they won't.
I would try if you can, to ensure that you are returning it as a defect for repair, rather than under the sales act. That way, if it is not considered to be a problem by Canon, you should get the same camera back, and overall it will not put the manufactured defects count up, (and thus will not be recorded, and not put the price up)
 
Just to get back on topic of sensors not LCD's, I've found the thread I was thinking of, post 5 in this link Clicky

Give it a go and let us know if it works.
 
It's not a dead Pixel, it's a teeny tiny alien from outer space. Treasure him, and he will tell you the secrets of how to create jaw dropping crop circles :D
 
Hawker said:
Just to get back on topic of sensors not LCD's, I've found the thread I was thinking of, post 5 in this link Clicky

Give it a go and let us know if it works.
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:thumbs:
Jo said:
It's not a dead Pixel, it's a teeny tiny alien from outer space. Treasure him, and he will tell you the secrets of how to create jaw dropping crop circles :D
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Thats what I am afraid of Jo, spiral images appearing in front of my very eyes each time I look at an image :lol:
 
i purchased a D300 from Jacobs photo and it had a dead pixel. I did a boxing photo shoot taking around 1000 pics at iso 3200 ... every one had an obvious and visible pixel out at A4 print size ... i demanded a replacement and was given one .. all sorted now
 
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