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nighttime scene

I took several night time photos and most of them have these transparent rings in the centre of them. Does anyone know what might be causing it?

I took the photo using a Canon Rebel T4i, a Canon EF-S 18-135mm lens with a Rocketfish UV filter. Camera settings ISO 400, f/5.6, 30.0s exposure.

Brigitte
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    Are these photos from a digital camera or scans of film? Did you have anything attached to the front of your lens? A filter? The pattern is moiré – osullic Sep 06 '17 at 21:03
  • This discussion on photo.net of diffraction patterns in images may be relevant as that effect to me, looks like a diffraction pattern. I wonder what camera and lens it was ? – StephenG - Help Ukraine Sep 06 '17 at 21:16
  • Relevant: the incorrectly named https://photo.stackexchange.com/questions/7626/what-is-the-newton-effect about Newton's Rings – ths Sep 06 '17 at 21:42
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    @osullic Nope, not moiré. Alan Marcus nailed the pattern. It is a beautiful example of Newton's Rings. As Alan asked, how did it get there? Clearly, you have been near water. That's a hint. Brigitte, tell us more about the stuff you have attached to the front of your lens that might be touching in the very centre. – Stan Sep 06 '17 at 23:34
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    Maybe it is Newton's rings, but it looks more to me like a perfectly centered reflection of the front of the lens reflected off the back of a flat filter. Kind of like in this question: What is causing the strange lighter circles in images taken with my Canon 15-85? – Michael C Sep 07 '17 at 04:09
  • What camera, lens, filter, etc. were used to take the photo? What exposure parameters (ISO, Tv, Av)? What, if any post processing? – Michael C Sep 07 '17 at 04:12
  • Newton's rings have a characteristic wave pattern with the succession of rings getting logarithmically narrower as they approach the edges as is shown. There were two smooth surfaces touching somewhere in the events leading up to the creation of the images. That it (they) are centred, leads me to believe they were produced during the exposure. – Stan Sep 07 '17 at 05:45

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This is called “Newton’s Rings”. They are an interference effect between reflections that happen when two reflective surfaces are in close contact. This is the same effect as a rainbow pattern seen in thin films like oil on water. It can happen when a slide or negative is placed in a plastic sleeve. Now you know what it is, now you must figure out what is causing it. Could happen when you scan a negative or a slide. You need to tell us more. What camera? Any optical filters mounted? It this film or digital? How did you reproduce the image?

Alan Marcus
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  • Spot-on observation, and nice connection with thin-film interference (oil rainbows on water). +1 – scottbb Sep 07 '17 at 02:50
  • I'd say it's the UV filter, considering what the OP wrote. – Noldor130884 Sep 08 '17 at 09:47
  • @ Noddor 130884 - Some filters are dyed gelatin sandwiched between flat glass covers. Newton's Rings can occur however; modern filters are dyed in the mass glass. Additionally, dust and scratches on a filter are not rendered sharp and clear. In other words, unlikely anything on or inside the filter would produce a tack sharp image. – Alan Marcus Sep 08 '17 at 15:48