Anyone Know What's Caused This?

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Name
Ian
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A friend of mine asked me what this was on his photo. It's not on every one but occurs intermittently. My thoughts were the card? Anything else (sensor, lens element) would surely see it on every photo...

It's the horizontal lines which you may need to click through to see although you might be able to make them out in the foreground grass. I've never seen anything like it before.


Squirrel
by Tom Swann, on Flickr
 



As I see it, Ian, card and sensor would show perfectly straight lines
and those are waaaay not. Because of that observation, my guess
would be a not too good sensor cleaning which can be verified by
inspecting it directly or through a loupe.

If confirmed, and other — but proper – cleaning will do it!. HTH. :cool:
 



As I see it, Ian, card and sensor would show perfectly straight lines
and those are waaaay not. Because of that observation, my guess
would be a not too good sensor cleaning which can be verified by
inspecting it directly or through a loupe.

If confirmed, and other — but proper – cleaning will do it!. HTH. :cool:
Agreed. The lines in the top half of the picture particularly look like moisture smears.
 



As I see it, Ian, card and sensor would show perfectly straight lines
and those are waaaay not. Because of that observation, my guess
would be a not too good sensor cleaning which can be verified by
inspecting it directly or through a loupe.

If confirmed, and other — but proper – cleaning will do it!. HTH. :cool:
Agreed. The lines in the top half of the picture particularly look like moisture smears.
But wouldn't moisture smears show in every photo, not just intermittently.
 
I'm sure that's digital artifacts, but couldn't tell you why it's happened.
Same here..

Zooming into the image (e.g. around monkey on the left) show areas of artefacts not just lines.

Q. Does it happen with images produced from RAW files?
 
Odd how it doesn't go across the squirrel.
When I first looked I though it was wire mesh in the grass.

Was the picture taken through glass or something?
 
But wouldn't moisture smears show in every photo, not just intermittently.
Any fault on the sensor will show more on some images and less on others. If the sensor has in fact been recently cleaned, I would put that as the most likely reason for the lines. If the sensor has not been cleaned, it must be something else. Ask your friend.
 
Thankyou all for taking the time to reply. It's given us somewhere to start.
 
Hope you come back with the cause, its interesting.

41909401892_7b3cbdf028_o.jpg
 
That's not a picture from a tv screen is it?
 
Zooming in on the image in Flickr shows that the lines ARE dead straight but are intermittent, making them look wavy at the posted size. Not sure what the cause is but I would suspect a card or reader problem. Re-downloading the image might clear it up but looking at the way the corruption follows the monkeys' faces and other well defined areas of colour, I think it's probably sensor or camera processor related
 
What I don't understand is why there are << chevron shapes in the noise.
 
It follows the contours of the face but isn't restricted to high contrast areas so is unlikely to be something like sensor overload.
Was this a raw file or an in-camera jpg?

I suspect the latter - and the something has gone a bit wangy with the graphics processor on the camera.

... I have no experience at all in diagnosing this kind of thing with cameras but it's got a certain amount in common with the kind of debugging I sometimes have to do in the day job ...

@HoppyUK is more likely to have a definitive explanation than anyone else I can think of.
 
It's affecting other images too. Some taken last night and I can guarantee no TV screen and no filters on lens. Also not taking stills from video.

Glad it's nothing obvious!

Thanks again for the replies.

Edit to add - he's trying a different lens, card and card reader this week. The latter being cheap things to fix if they are the problem.
 
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It follows the contours of the face but isn't restricted to high contrast areas so is unlikely to be something like sensor overload.
Was this a raw file or an in-camera jpg?

I suspect the latter - and the something has gone a bit wangy with the graphics processor on the camera.

... I have no experience at all in diagnosing this kind of thing with cameras but it's got a certain amount in common with the kind of debugging I sometimes have to do in the day job ...

@HoppyUK is more likely to have a definitive explanation than anyone else I can think of.

Not much to go on, but looks like some kind of digital artifact. Could be anywhere in the chain from the sensor back, but usually turns out to be a card problem.
 
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It's affecting other images too. Some taken last night and I can guarantee no TV screen and no filters on lens. Also not taking stills from video.

Glad it's nothing obvious!

Thanks again for the replies.

Edit to add - he's trying a different lens, card and card reader this week. The latter being cheap things to fix if they are the problem.
Suggest he also to takes some RAW images to see if the artefacts are still visible in the edit. Might also be useful to try a different computer system for downloading and processing the files.
 
Suggest he also to takes some RAW images to see if the artefacts are still visible in the edit. Might also be useful to try a different computer system for downloading and processing the files.

I asked for a copy of one of the raw files yesterday. Will be interesting to see.
 
This is purely an observation - but it doesn't seem to affecting any of the deep shadows. So I'd say it's not a mechanical issue - like smears on the sensor - but a processing issue.

As mentioned, this could be any point in the chain, so it's worth starting with the things that are easiest to check.

Different card. Different card reader. Different PC. Get the camera to export a RAW image only. Get the camera to export a JPEG image only. Don't process it in LR/PS.
 
Looking at the other images, it appears to me to only affect areas that are green or have significant green intensity. Sensor issue?
 
A glitch in the matrix :D
 
Non of the dark parts of the image seem to be affected, look at both the faces and the squirel's tail, no, or very few, issues with them. Also dark bits on the grass/leaves seem to be clear of the issue as well. I'd thus guess that it is done in the processing, probably in camera processing.
 
Another wind up?????
Definitely not. When I saw the first image I suspected something connected with an electronic shutter. Then I looked at the EXIF (and camera model). Looked at the OP's friend's Flickr feed. I was expecting to see similar banding in other similarly exposed images. However, the only ones that display this feature seem to be limited to areas containing significant green luminosity. Areas devoid of green, notably blue and red areas, are entirely devoid of banding. A Bayer filter consists of 50% green. I put 2 and 3 together and came up with what I felt was a reasonable hypothesis.

It doesn't look like something that sensor cleaning would solve. Similarly, I doubt that it's a card problem. Happy to be proven wrong.
 
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Looking at Mike's crop, the issue is clear on the monkey's head as well as around the green bits.
And brown is composed of? The other images don't seem to contain any banding in red and blue areas.
 
Not "significant green intensity". Certainly not as green as the unaffected blob just by the monkey's nose.
 
I guess it could also be a confused noise reduction algorithm (if that's how you spell Al-Go-Rhythm?)
 
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