# Help-What is wrong with my camera/lens???



## alibongo (Nov 7, 2009)

I recently bought a used 28-135 IS lens for my canon 20d. I took it out tonight to get some nighttime hdr shots, when I got home this is what I found..




What could cause the black strip at the top of the photo? Also, the pic looks to be really low quality, it was shot at iso 100 on a tripod with a remote..In addition, if you look at the scale to the left of the picture it looks like there is alot of static involved with the image..

Here is another one, instead of the black at the top, there are greenish black strips on the sides, if you go to my imageshack page and zoom in on the picture you will see that there is the same type of static as the first on the scale. Again, iso 100 shot on a tripod with remote..







The previous photos I have taken with this camera on several different lenses have all been okay. Even nighttime hdr using photomatix, they have all been sharp and clear. 

What could be the problem?


Thanks in advance for your help...

Alex


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## Garbz (Nov 8, 2009)

Post some non-tone mapped shots please. The quality of an image is very hard to judge due to HDR processes. Even with the finest gear some HDRs are just horrid due to the software not matching the tone or aligning the images correctly.

As for the green stripe, again is it there in non-HDR images? Photomatix can introduce artefacts and things like that quite easily, though I haven't ever seen it appear quite as consistently as that.


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## alibongo (Nov 8, 2009)

Sure, the hdr seems to show the problem better, but in the pics below check out the left side and right sides, the left seems to be worse than the right.. It is in all pics with long exposures but seems to be fine with any daytime pictures..


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## Garbz (Nov 8, 2009)

The HDR masked the fact that the stripe went vertically over the entire frame. On the HDR I thought it was flare or something, but I'm afraid to say it looks like a camera problem.

The quality of the image is fine by any standard, so I think HDR would have caused any concerns you have there. Even at ISO100, HDR pushes a lot of brightness out of dark areas creating very crap image quality. I have only managed to do one somewhat decent night-time HDR, and I have seen few examples of it working well too. 

But the stripe, it's consistency to the edge of the frame, and the fact that it appears over both exposed and black areas is really not good  I don't like saying it but give Canon support a call.


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## ruaslacker2 (Nov 8, 2009)

Did you remember to turn off the IS while shooting from a tripod ?  It will still try to compensate causing focus problems.


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## alibongo (Nov 8, 2009)

Yes, the IS was off in all pictures. Garbz, so you think it may be a camera problem not a lens problem? I will have to try out another lens but it seems like I never had this problem before shooting night shots with any other lens.


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## Garbz (Nov 9, 2009)

For the simple fact that lenses are round, and bend light into all sorts of angles, I think because of the very perfect consistency of those green lines it's a camera problem.

Definitely try and narrow it down first with another lens though.


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## Flash Harry (Nov 9, 2009)

Looks a bit like when you shoot at a higher SS than sync speed when using flash, I think you may have a slight problem with a sticky shutter curtain. H


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## UUilliam (Nov 9, 2009)

looks like you have a lens hood on?
maybe catching vignette off that?


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## Tiberius47 (Nov 10, 2009)

Take a picture of a uniform surface, such as a wall so we can see more clearly what the problem is please?


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## Garbz (Nov 10, 2009)

If you're going to do that, also take a very long exposure with the lens cap on. From the looks of things the green effect comes up regardless if light is hitting the sensor or not. Try giving us a 5-10min exposure, or a shorter exposure at higher ISO.

Flash sync would only happen if there was something to actually illuminate with the flash.
I have never seen vignetting perfectly square across the top of a frame.


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## alibongo (Nov 10, 2009)

Alright, sorry for the delay, here is a 5 min exp with the cap on manual focus, IS turned off at ISO 400. The camera wasn't perfectly still but didn't think that would matter:






By alexchallinor, shot with Canon EOS 20D at 2009-11-10


Does anyone know what the thing is in the bottom left corner? Also, are the tiny spots dead pixels?!?! It's strange how the green is now focused in the center and not the sides..



Thanks again for the help!


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## alibongo (Nov 10, 2009)

Alright, sorry for the hold up, the first pic is with the 28-125 IS which I thought was the trouble. ISO 400, Manual focus, IS off. The second pic was with a 50 1.8 with the same setting as above. The 3rd pic is with the 50 1.8 but with a 60 sec exposure, it seemed to produce similar results to the first pic. Also, are all those spots dead pixels?!?!?





By alexchallinor, shot with Canon EOS 20D at 2009-11-10





By alexchallinor, shot with Canon EOS 20D at 2009-11-10





By alexchallinor, shot with Canon EOS 20D at 2009-11-10


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## alibongo (Nov 11, 2009)

Here is one shot for 5 min ISO 400 IS off manual focus with the cap on.. Are all those spots dead pixels?


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## alibongo (Nov 11, 2009)

Same stats with a different lens..


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## Overread (Nov 11, 2009)

I would say its one of two possible problems 
1) duff memory card
2) duff/dirty sensor.

The first is easily tested and you cna do that by formatting the card in camera (not in the computer). Then see if the shots keep repearting the effect. If you have a second card try using that instead as well.

2) If its dirt on the sensor (like oil possibly from internal components squirting a bit onto the sensor - the 5D had this problem) then you can have it professionally cleaned out (best done since oil is a swine to get of well). However I would rather send thecamera off for a proper servicing in this case otherwise your likley to end up spending even more should the clean not prove effective (unless you have a friend who can clean the sensor well for you)


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## Garbz (Nov 12, 2009)

1) In order to consistently cause a colour shift in an area the memory card would have to have every group of bits wrong in the same place. More likely diagnostic of this would be if the image didn't open, or had horribly corruption.

2) Dirty sensor would be unlikely to produce this since this image is dark. If you shoot with the lens cap on you don't see black spots or grease on the sensor, unless there's a light source in the camera body, but really who would design something like that.

Unfortunately that really only leaves one problem, and that is something is wrong with the sensor, or the analogue to digital converter. Now it's time to call Canon  

Also yes those are dead pixels, but that is a given. If you increase the sensitivity and increase the time the pixels are on, it all turns into a question of when and how many pixels will be dead. They are reset on the next exposure though. My first dead pixel appears as soon as 1/10th at ISO800, or about 2 min at ISO100.


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## alibongo (Nov 12, 2009)

I guess I will call Canon today. Garbz, thanks for your help your definitely appreciated.


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