Moire

[Shadowman]

Pattern appears onscreen when zoomed out but not in print and not when zoomed in. I have LR which has slider to remove but didn't need to use it.



f/13, ISO 125, 1/1000sec, 85mm f/1.8
Found similar discussion at this link.
What is this pattern?

[Rufus]

Was the model's name Moira by any chance?

[george013]

Pattern appears onscreen when zoomed out but not in print and not when zoomed in. I have LR which has slider to remove but didn't need to use it.



f/13, ISO 125, 1/1000sec, 85mm f/1.8
Found similar discussion at this link.
What is this pattern?

Never use clothing like this. You will not see them on tv either.

George

[DanK]

Interesting. Thanks for posting.

I went back to the earlier thread that you linked to. I think we have three different phenomena.

1. Moire induced by the particular image, usually with cameras that lack an AA filter

2. Moire that is induced by an interaction between the image and the pixel density of the screen.

3. Moire-like patterns that are caused when lens profiles correct for barrel or moustache distortion.

I think #3 was the issue in the earlier post. That doesn't seem to be the issue here. I'm guessing it's #2.

here. I suspect that what you have is moire induced by the particular

[Shadowman]

Was the model's name Moira by any chance?

Depends on her origins, could be Maury or Mawh. 😳

[Shadowman]

Never use clothing like this. You will not see them on tv either.

George

Yes, sometimes the photographer can make suggestions.

[Shadowman]

Interesting. Thanks for posting.

I went back to the earlier thread that you linked to. I think we have three different phenomena.

1. Moire induced by the particular image, usually with cameras that lack an AA filter

2. Moire that is induced by an interaction between the image and the pixel density of the screen.

3. Moire-like patterns that are caused when lens profiles correct for barrel or moustache distortion.

I think #3 was the issue in the earlier post. That doesn't seem to be the issue here. I'm guessing it's #2.

here. I suspect that what you have is moire induced by the particular

Outcome was interesting, I even wondered if angle of view would cause it in print but it did not.

[Manfred M]

If anyone remembers either high school or first year university physics, moiré patterns are light interference patterns when solid linear patterns with a transparent gap interact with similar linear patterns.

In these images the culprits are the dress and the patterns of how the elements of your computer screen are laid out. As luck would have it, at certain magnifications these two sets of patterns line up, but if you change the size of the image, the lines in the dress and lines in the computer display don't line up and the problem goes away.

I see this from time to time when I am shooting and see moiré patterns on the screen on the back of my camera. When this happens I crank up the magnification and if the pattern goes away, no issue, but if it doesn't I know the issue is related to the subject and sensor patterns interacting and the recorded image is problematic. A retake at a slightly different position of magnification cures the issue. That being said, I can only remember having a "real" moiré issue once or twice. Modern cameras with their much finer pixel pitch seem to be more immune to this effect than older cameras with larger photo sites. AA filters were in common use to try to prevent that issue, but they also softened the image.

[Shadowman]

A very old blog but does discuss different types of moire development.

https://the-print-guide.blogspot.com/2009/12/moire.html

[Manfred M]

A very old blog but does discuss different types of moire development.

Not only very old but rather irrelevant to most of the membership as it primarily deals with half-tone screen issues used in offset printing; printing presses not photo quality ink jet printers. Not something that people that primarily show digital images would find relevant.

He also deals with scanning film on a drum or flatbed scanner. Again, not something a lot of members will do.

The very short section on demosaicing moiré is the only part that is really relevant to digital photographers. The 2009 and earlier cameras and the relatively low resolution is not particularly applicable to modern cameras.