5D MK 2 Discussion: Black dots at high exposure

[PictureFreak]

There has been a lot of word going around that black dots are appearing in areas of high exposure with the 5D MK 2. Here are some crops taken at various ISO of my images. I think the problem of the black dots only start to appear at high ISO. Seems that many 5D MK2 users are experiencing this problem to a varying degree of severity. The black spots consistently appear on the right side of the street lamps. Below is an image that is suffering quite badly from the black spot problem

http://fakechuckwestfall.wordpress.c...ark-ii-****ed/

Hopefully Canon will offer a fix for it asap. Seems that this problem also appeared on the pre-production models. Wonder if Canon spotted it then???

Comments and opinions anyone? Thanks

ISO 100



ISO 800



ISO 1600



ISO 6400



ISO 12800

[metalgear]

just to clarify , you took these shots on your "retail stock" 5D mk II ?

1. can you repeat the last shot here http://img.photobucket.com/albums/v1...8162605bmp.jpg
at different ISO's to check ?

2. are you shooting on raw or jpeg ? if RAW try using another RAW converter and shooting in jpegs to try to isolate the fault.

3. suggest you take precaution and register this with your shop immediately, just in case.

curious to see your findings.

[PictureFreak]

Originally Posted by metalgear just to clarify , you took these shots on your "retail stock" 5D mk II ? 1. can you repeat the last shot here http://img.photobucket.com/albums/v1...8162605bmp.jpg at different ISO's to check ? 2. are you shooting on raw or jpeg ? if RAW try using another RAW converter and shooting in jpegs to try to isolate the fault. 3. suggest you take precaution and register this with your shop immediately, just in case. curious to see your findings.

Yep, this is the 5D Mk2 i got from MS Color last week

1. Nope i am not facing that problem currently, hopefully never....Like i mentioned earlier, different cameras are affected to varying levels of severity. The image above seems rather bad...Anyway, here are some more crops. Did some sharpening and noise reductions...

ISO 100



ISO 800



ISO 12800



All seem ok to me

2. I shot all in JPEG. Will try to test out RAW shots in the next couple of days

3. I already shot Canon Technical Support an e mail. Letz see what they say...

[phoakm]

By looking at the pictures, the so call black dots happened when using high ISO.
Could it be the sensor interpolation mechanism having issue? The matrix getting more bigger.

[SianZronG]

maybe the NR in action? what was the NR setting?

[PictureFreak]

Originally Posted by SianZronG maybe the NR in action? what was the NR setting?

In-camera noise reduction was set to standard....There is quite a lot of technical discussion going on abt this on DPreview....

[surefire]

It's a big problem - lots of threads discussing this issue:-

http://forums.dpreview.com/forums/re...hread=30222755

http://forums.dpreview.com/forums/re...hread=30252536

http://photo.net/canon-eos-digital-camera-forum/00RewZ

http://photography-on-the.net/forum/...d.php?t=609860

I would hold off on buying the MkII until there is official response from Canon. Apparently, it may be hardware-related and can't be solved by a simple firmware upgrade.

[bernstein1234]

Originally Posted by surefire It's a big problem - lots of threads discussing this issue:- http://forums.dpreview.com/forums/re...hread=30222755 http://forums.dpreview.com/forums/re...hread=30252536 http://photo.net/canon-eos-digital-camera-forum/00RewZ http://photography-on-the.net/forum/...d.php?t=609860 I would hold off on buying the MkII until there is official response from Canon. Apparently, it may be hardware-related and can't be solved by a simple firmware upgrade.

I'm not sure if this is batch problem, but apparently the 5D2 which I bought just yesterday did not have this problem.

Here's a sample showing high high ISO (12800) with high contrast area:

Original image at ISO 12800


Cropped portion

[surefire]

Originally Posted by bernstein1234 I'm not sure if this is batch problem, but apparently the 5D2 which I bought just yesterday did not have this problem. [/IMG]

I think you need to look at small point sources of light against a dark background - for example, light bulbs on a Christmas tree. At least that's what I have concluded from the samples I have seen. There were many people who thought they didn't have the prob with their Mk II but realised later they were looking at the wrong place/wrong types of samples.

It's also discussed in the Chinese forums:-

http://forum.xitek.com/showthread.php?threadid=582285

[bernstein1234]

Originally Posted by surefire I think you need to look at small point sources of light against a dark background - for example, light bulbs on a Christmas tree. At least that's what I have concluded from the samples I have seen. There were many people who thought they didn't have the prob with their Mk II but realised later they were looking at the wrong place/wrong types of samples. It's also discussed in the Chinese forums:- http://forum.xitek.com/showthread.php?threadid=582285

Hmmm no offence to your post but the Chinese forum said (directly): "the original 5D and the Sigma (they call it 死马 lol) DP1 also have this problem".. and "不好意思地告诉大家，D3也是有的，只要曝光时间长，就有，至少我的有" = sorry to tell you, D3 also got this prob, as long as you long exposure then have this prob, at least for me"....

[solasido]

just a though... noise artifacts are normally more visible in darker area.. it could be that the darkspots are kind of noise reduction mechanism? logically if the noise dots in dark area are converted to black/dark-dark grey dots, they will be less visible to cheat our eyes..

[surefire]

Originally Posted by bernstein1234 Hmmm no offence to your post but the Chinese forum said (directly): "the original 5D and the Sigma (they call it 死马 lol) DP1 also have this problem".. and "不好意思地告诉大家，D3也是有的，只要曝光时间长，就有，至少我的有" = sorry to tell you, D3 also got this prob, as long as you long exposure then have this prob, at least for me"....

this is not a Canon vs Nikon issue so no need to get so defensive lah. i am not a fanboy, just looking for the truth. if you read my links, you will find that artifacts found in other cameras are not related to this issue. here, all the black dots appear only on the right hand side of the bright point. also, it doesn't appear only on long exposures.

[surefire]

Originally Posted by solasido just a though... noise artifacts are normally more visible in darker area.. it could be that the darkspots are kind of noise reduction mechanism? logically if the noise dots in dark area are converted to black/dark-dark grey dots, they will be less visible to cheat our eyes..

see my response above. if it was noise artifacts, they wouldn't just appear on the RHS. see post #81 of this thread too for a sample closer to home-

http://www.clubsnap.com/forums/showt...=442495&page=5

[solasido]

oh man.... disaster.. the black area after the spot light is so visible..

reminder again... dun rush to buy any new released product..

Originally Posted by surefire see my response above. if it was noise artifacts, they wouldn't just appear on the RHS. see post #81 of this thread too for a sample closer to home- http://www.clubsnap.com/forums/showt...=442495&page=5

[PictureFreak]

Originally Posted by solasido oh man.... disaster.. the black area after the spot light is so visible.. reminder again... dun rush to buy any new released product..

Here is a posting that just came in on Canon Rumors

"Much ado about nothing
I’ve talked to countless people with 5D Mark II’s that have used other cameras as well. The black dots seem to affect a lot of cameras from Canon, Nikon and even Sony. The nature of digital photography?
Various people have also said there has been no issue at all, even when they succumb to severe pixel peeping. So for now, I’d say the camera is operating as usual. Perhaps a firmware upgrade will make it less visible. It’s one of those things I don’t have the technical knowledge of to really get to the root of it.
Still safe to buy a 5D Mark II…… the only issue is actually getting one!"

http://www.canonrumors.com/

[panzerpunk]

i don't see any black dots??

[doodah]

Originally Posted by surefire I think you need to look at small point sources of light against a dark background - for example, light bulbs on a Christmas tree. At least that's what I have concluded from the samples I have seen. There were many people who thought they didn't have the prob with their Mk II but realised later they were looking at the wrong place/wrong types of samples.

Actually, bernstein1234 is looking at the right thing. Even the black dots on Picturefreak's shots are not too obvious to me, as pointed out by panzerpunk.

Now, these are obvious after some magnification beyond 1:1.

[PictureFreak]

Originally Posted by doodah Actually, bernstein1234 is looking at the right thing. Even the black dots on Picturefreak's shots are not too obvious to me, as pointed out by panzerpunk. Now, these are obvious after some magnification beyond 1:1.

Yes i agree, it is very hard to see the black spots under normal viewing. I cannot see the black spots even when viewing my images full screen on a 20 inch. I am quite sure they won't show up in most prints as well.

[panzerpunk]

could it be dynamic ranges of colours from something that ranges from FFFFFF region to something close to 000000 region in a matter of 100-200 pixels or something?
that will give linearly 82.9k colour changes per pixel which the processor can't resolve?

ok that sounds illogical. what if you take a picture of a bright background with a very dark spot, will i see white/greyish dots if the same theory applies?

[FeiFei]

Sorry if this is OT but I can see black dots here

http://forums.dpreview.com/forums/re...hread=30265749