7

Can anyone explain these wavy lines forming a across in the photo?

I used a Nikon AF-S DX 18-140mm 3.5-5.6G ED VR at 140mm, ISO was set to 160.

Here is a 1:1 pixel crop:

enter image description here

enter image description here

enter image description here

enter image description here

  • yes, sorry its a 18-140mm DX VR,with VR on. 100% crop. – Barco555 Sep 22 '18 at 13:26
  • 1
    Was this taken through a chain link fence, or perhaps chicken wire, or some other diamond-shaped fencing? – scottbb Sep 22 '18 at 21:30
  • 2
    Was there any kind of filter on the front of your lens at the time? If so, exactly what filter was it? – Michael C Sep 23 '18 at 3:39
  • 1
    @scottbb Yeah, but I still think it's kind to ask to show appreciation ;) – Alexander von Wernherr Sep 27 '18 at 5:35
  • 1
    @AlexandervonWernherr Truly classy. =) – scottbb Sep 27 '18 at 5:36
-3

It appears to be diffraction from sunlight passing through the leaves in the tree. It's the same thing you'd get intentionally from using a cross screen filter. Had the focus been on the leaves, I expect that the classic "star" pattern would be more obvious.

  • That doesn't explain the similar second 'X' on the left of the second example frame where no backlit trees with gaps between the leaves are directly behind it. – Michael C Sep 23 '18 at 3:42
  • @MichaelClark There was initially only the 1:1 example photo in the question, however I agree with you that this doesn't seem a wholly satisfying explanation. – Kat Sep 23 '18 at 9:38
  • 1
    With the additional pictures provided now, which were not initially present, I'm inclined to agree it probably is not diffraction in the trees. – user10216038 Sep 23 '18 at 15:36
9

It strongly appears you were shooting through a chain-link fence, chicken wire, or something else with a diamond-shaped pattern. Here is where I think the fence or wire would be (apologies for my unsteady hand drawing on a laptop trackpad):

enter image description here

enter image description here

The latest photo you uploaded shows even more distinctly what could plausibly be fence wire in the upper right corner, crossing diagonally across the sky in the background. In this photo, your lens appears to be further away from where the putative fence is (i.e., more chain links in the near field of view). Another poorly hand-drawn demonstration where I think the fence is:

enter image description here

The fencing would cause wavy lines parallel to the wires, that only shows up in the defocused areas of your image. In this thread at dpreview.com, user Tom Axford demonstrates how several narrow strips of paper held in front of the lens creates parallel wavy lines:

enter image description here
Out-of-focus background from dpreview.com discussion

enter image description here
Out-of-focus background with black strips held in front of lens

Now, the reason I think your entire background doesn't have wavy lines is because the purported fencing is a bit further from the front of your lens than the paper strips Tom Axford used to demonstrate the effect. Thus, the background region immediately surrounding each of the wires in the fence would demonstrate diffraction (the cause of the parallel wavy lines).

  • I'd agree with and upvote your answer if the OP had not said "No fencing" in a comment. – Michael C Sep 23 '18 at 3:44
  • 1
    @MichaelClark Understood. I focused more on the "Can anyone explain these wavy lines..." part of the question. Yes, it can be plausibly explained, and xiota provided very compelling reproduction of the effect through fencing. So perhaps the followup should be, "are you sure it wasn't shot through fencing?", or "how sure are you that it wasn't shot through fencing?" – scottbb Sep 23 '18 at 3:47
  • 1
    The fencing idea seems reasonable except that fencing similar to the diagram drawn would need to be within a few feet of the camera and hard to miss by the OP. Fencing farther away would need non-functionally large grid openings to come anywhere near the suggested diagram. – user10216038 Sep 23 '18 at 21:40
  • @user10216038 Absolutely, because the purported fence is not clearly visible, it must be quite close to the lens. As a matter of fact, you can make some calculations for probable distance from the lens, assuming 2" or 2 1/4" chain link fence (most common, and economical). The lens focal length and sensor size are known. The rest is geometry by similar triangles. – scottbb Sep 23 '18 at 21:48
  • 1
    I don't know why anyone would deny the presence of a fence, but I'm inclined to disbelieve the "no fencing" claim. At the very least, there is something very similar to a fence present. – xiota Sep 25 '18 at 2:25
5

Agree with scottbb's assessment, you are likely shooting through an obstruction with a diamond pattern, such as a chain-link fence or a net. (Consider this a supplement to scottbb's answer.)

  • The "wavy lines" criss-cross in a diamond-shaped pattern, as scottbb illustrates.
  • There is a bluish-gray haziness following the same diamond pattern.
  • Examination of bokeh balls within the image show "shadows" of the obstruction.

    1

Here is an independent replication of scottbb's overlays. Rather than draw in where I think the fence may be, I highlight only portions of the image where I can see "wavy lines" or a clear difference in clarity from the surrounding area (haziness). I did this while zoomed in extremely closely, so I could not see whether a diamond pattern was being formed until after zooming out at completion.

img1 img2

Here are some pictures of a chain-link fence for comparison. Notice the tone of the haziness reflects the color of the fence:

fence-1 fence-2 fence-3

Strongly doubt any of the following:

  • "... diffraction from sunlight passing through the leaves in the tree." Such diffraction is unlikely to create such a regular diamond-shaped pattern. "Wavy lines" are also present where there is no sunlight passing through leaves.

  • Glare, which can create linear streaks of haziness with flare spots that correspond with the lens' glass elements. Glare is unlikely to create a criss-cross, and flare spots are absent in the images.

  • Obstruction by reeds of grass. While reeds of grass would produce a criss-cross pattern, it wouldn't be so regularly spaced. The haziness would also be expected to have a brownish or greenish tone from color of the reeds.

  • "Smearing" after cleaning the lens with a dirty cloth. In a diamond pattern?

  • Heat waves. In a diamond pattern?

  • A diamond pattern drawn on a filter or the front element of the lens. This possibility can be distinguished from another obstruction by examining multiple uncropped images from different perspectives. A drawing on the lens would not change position relative to the rest of the scene.

  • Supernatural phenomena.

  • I meant to get pictures of blur through chain link fence. +1 for beating me to it! – scottbb Sep 23 '18 at 1:56
  • 1
    @scottbb Considered donating them to your answer, but thought mentioning haziness and "shadow" in bokeh warranted writing separate answer. – xiota Sep 23 '18 at 1:58
  • 1
    Yeah, I didn't make it very clear in my answer. The lighter shaded haziness was part of the giveaway. Also, when looking at the X pattern in the 1st image in the question, I couldn't get over the part in the middle of the X where they "cross over" each other, just like the wires in a chain link twist around each other. – scottbb Sep 23 '18 at 2:01
  • This post makes a strong argument, but the OP said there was no fence. – Patrick Taylor Sep 26 '18 at 7:35
  • 1
    @PatrickTaylor People claim all sorts of things. I'm inclined to disbelieve the "no fencing" claim. – xiota Sep 26 '18 at 7:39

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.