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Is it normal or not to have such stripes in a photo taken with strong backlight? Photographed on a new Canon 700D, jpeg from CR2.

enter image description here

  • it's a shame - I think it's a great photo. Framed a little too tightly maybe – osullic Nov 1 '18 at 15:55
  • What was the exposure like? Did you push this significantly in raw conversion? – mattdm Nov 1 '18 at 19:54
  • @mattdm, yes, I pushed it much, but the stripes are seen even without any edits of CR2 file. – apazent Nov 1 '18 at 20:24
  • This definitely isn't normal, even pushed that much. You should try taking some dark frames, with and without the lens (i.e. with lens/body cap on.) – Gene Nov 2 '18 at 23:19
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No, it is not normal. These stripes look a lot like Newton's Rings, even though they aren't rings. Did you use some filter in front of the lens, which might have created those patterns?

  • No, there was nothing between the lens and people on photo. Please open the higher resolution: the shape of stripes is quiet regular, from whole photo from left to right. – apazent Nov 1 '18 at 20:21
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    It is, and it isn't regular. The width of the stripes is highly variable (roughly sinusoidal). They might also be ever so slightly curved. I can't be certain. My money is on a bad filter capacitor inside the camera, because this looks like AC hum bleeding into the internal circuitry of the camera. – dgatwood Nov 1 '18 at 21:12
  • @dgatwood, yes, I meant this sinusoidal regularity. Curved - not sure, it seems they don't vary along the width. So can I state the camera is defective? – apazent Nov 1 '18 at 21:34
  • The only way to know for sure would be to repeat the experiment with a different lens, and try to rule out other things, like some sort of weird optical effect caused by the slightly out-of-focus window screen, inspect the lens for any damage/smudges/unexpected cellophane stuck on the rear element, unusual light sources just to either side of the photo, etc. Rule everything else out. – dgatwood Nov 2 '18 at 5:50
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    Also, this isn't shot in live view mode, is it? If so, try not doing that and see if the problem goes away. It might be interference caused by a defective backlight inverter. – dgatwood Nov 2 '18 at 5:52
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Based on your comment: your image is super-underexposed. From the metadata:

  • Exposure time: 1/125s
  • Aperture: f/5.0
  • ISO: 1600

and it looks like, from the link you gave, that you've pushed this up about three stops in post processing. (That is, to the equivalent of ISO 12,800.)

It is not at all unexpected to see artifacts like banding when taking an underexposed photo at high ISO, and even less unexpected when you push up the shadows like that.

In this particular example, the banding seems rather strong, so there may be some problem. But... I'm also reminded of the old joke: "Doctor, it hurts when I do this." / "So, don't do that!"

  • Okay, I agree, it's super-underexposed and ISO value is relatively high (not so high, usually I face problems with ISO 6400 or at least 3200). But the stripes are seen on the highlighted parts of unedited image too. Is that OK? – apazent Nov 1 '18 at 21:00
  • Also, why do we see sinusoidal waves, not just white noise? – apazent Nov 1 '18 at 21:03
  • I don't know about "OK", but especially for a 2013 camera at ISO 1600 and underexposure (see this question), I'm not shocked. – mattdm Nov 1 '18 at 21:32
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    The patterns of the stripes indicate this is more than just noise from underexposing and then boosting in post. I've shot Canon digital cameras enough to know what the banding one gets from pushing exposure too far with Canon sensors looks like, and this isn't only that. Something else is also going on here. – Michael C Nov 2 '18 at 4:09

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