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37

This is moiré. It occurs because a screen is actually a grid of squares that are being used to make the image. When it ends up trying to be mapped to another grid of pixels (either by being captured by a sensor or by scaling) points of light or pixel data don't line up exactly. Some pixels get 2 pixels of information, some get the border between pixels. ...


11

Human eyes see moiré in the overlapping of two regular patters. In photos you see the photographed pattern overlapped with the pixels, which form the second pattern. Of course you can see moiré with your naked eyes, but you need two overlapped patterns in the scene. Your eyes don't add one of them.


9

There doesn't appear to be any moire in the image itself. What you are seeing are scaling errors when the image is resized by a particular application for display on a particular size screen or print. To solve this you can create, optimize, and export different resolutions of the image for different display environments. For instance the display on a ...


9

As your existing (+1) answer says, it's a Moiré pattern. But you see it particularly when the image is scaled. You don't say what does the scaling, but I'm guessing you're just zooming the display, or pasting into Word/Powerpoint/etc., in which case you may benefit from scaling the image using a different method in the GIMP (free), Photoshop (expensive) or ...


9

And it's not just an imaging artifact. It can occur whenever fine lines in one orientation intersect fine lines in another orientation. It is common in fabrics where the spaces between the threads are larger than the threads, thereby allowing light to pass through and interact with the pattern of threads in other parts of the fabric. The moire in this ...


8

The patterns from Moire Demonstration Kit work best and print themselves without moire more easily than the test patterns from the Moire Fringe AF Adjustment Method answer — either circles or fine mesh. The concentric-circle patten in particular should be very effective, as it has decreasing distance between each circle making it almost guaranteed to ...


7

"The pattern caused by the shadows and the grill together looked very much like moiré to me" It was moiré. Two overlaying pattern causing combination patterns is what a moiré pattern really is. When moiré pattern appears in a digital camera, one of the patterns is the pixel grid of the camera sensor. As humans doesn't have a pixel grid in their eyes, a ...


6

Moire occurs because the scene is sampled at a discrete resolution which is the nature of digital imaging. There is nothing to do about that but reduce the frequency of the signal reaching the sensor. In fact, moire occurs in monochrome sensors too which have no sub-pixels. The matrix of pixels form a fixed grid to sample an image formed by incoming light ...


5

There are a few ways to deal with moiré and none of them is a guarantee in every situation: Moiré adjustment tool/brush/filter in your post processing tool(or manual techniques with similar impact, manually blur areas of the image with moiré) Stop down your aperture to introduce diffraction Use a higher resolution sensor Have the model use a different ...


5

The effect is called Moire. It is caused by the grid pattern of the photosites in your sensor and the grid of pixels in the screen interacting. It happens when the grids do not exactly line up. It can occur with any gird or parallel lines. It is explanined in more depth here. To reduce this effect try to reduce how much of line the screen is to the sensor.


5

Even I had experienced similar problems while shooting night sky photos and later stacking them together although not as apparent of a moire pattern as you have. after a bit of troubleshooting, I found out that by disabling Lens Correction before stacking the photos and applying it after stacking eliminates the problem. A side note would be that I used ...


5

I'm guessing this has to do with two overlays that were very slightly misaligned from each other such that the small variations in each image due to the Bayer matrix become apparent. If so, this is a rare case where working in raw is actually hurting. Put another way, the raw data has some regular high frequency content due to the Bayer matrix. Normally ...


5

The moiré effect is due to spatial frequency folding. If a repetitive pattern (cloth, floor tiles, roof tiles...) in your picture is going to be about 1px after scaling, you get moiré. The best cure is to blur the image before scaling it down, to remove those kind of details, which won't be visible in the final image anyway. Roughly, the blur radius should ...


4

If the problem only happens when scaling, then that means the scaling is bad. A simple/low quality algorithm was used and therefore the scaled image looks differently than the original. With a quality scaling this does not happen. It would help if you would make the original image available. What software did you use to scale the image? For a quick check ...


4

This is known as Moire and generally occurs in patterns outside of nature. When the fine patterns in the image intersect with the camera sensor, these moire effects occur. If you are using Lightroom, then it is very easily corrected. Open your image in Lightroom and go to the Developer Module Then click on the Adjustment brush. When the sliders for the ...


4

You are attempting to image a label, signage that was produced by lithography. This method breaks up the original image so that it is comprised of tiny dots of colored ink. Each will have a different dot size and coloring. This type of image is called a half tone. Now the digital camera images is fabricated using a comparable method. The digital imaging ...


3

I solved the mystery! I shoot RAW, edit in Lightroom, and export to JPEG. In LR I normally check "Enable Profile Corrections" under Lens Corrections. When I unchecked this box, the photo exported without the moire. Not sure what's going on under the hood, but lesson learned.


3

You have diferent issues here. Lets separate them. 1) You have a bright wall and dark people... It is the same case as if you have a bright window with people on an interior. Your options are limited. Use aditional ilumination, like firing a flash as fill light. If you are shooting from far away this could not work. But if you have permissions you can use ...


3

As other answers state, the effect is called Moire. But why does it happen when you downscale or zoom-out? As prevoiusly stated Moire happens when two patterns interact, specially if the two patterns have a "frequency" (read size of the repeating characteristic) close enough to each other. What happens next is a mathematic relationship between the patterns, ...


3

Moire is a kind of "aliasing" - an effect where something is seen (or heard) incorrectly because the frequency of the source is too high for the sensor (in a picture high frequency is caused by repeating patterns where the individual pattern is too small to be recorded). Aliasing does happen in the human eye (at least in theory - because you can't really ...


3

There are probably at least two things going on here that are contributing to the artifacts you see in your photos: Moire. When you take a picture of a regular pattern (like the rows and columns of a large LED display screen) the pattern you are photographing and the pattern on your camera's digital sensor can interfere with one another. It's like looking ...


2

Most people will be reading this on a moiré generator, also known as an LCD screen. Photo from Useful Photo Tips: Photographing Screens.


2

If you happen to be in Paris then you can you can stop by the Centre Pompidou (the inside out modern art museum), head up to the fourth floor and walk to the end of the atrium where you'll find this piece: It's a series of wire shapes in front of a striped background which represents the most severe moire torture test I've ever put a camera through. If you ...


2

Take a picture of anything with a small repeating pattern. Preferably set up the perspective so that the size of the pattern as it ends up on the sensor varies accross the picture. This varies the frequency of the pattern on the sensor, which is useful since different effects may appear at different frequencies. It will also help in comparing the cameras ...


2

To clarify what the people above said, the pattern you are seeing probably comes from photographing the gaps between pixels. For various reasons (e.g. camera tilt) they won't be perfectly aligned with the pixels on your CCD and in the resulting image. When downscaling, the algorithm has to decide what color will be a resulting pixel based on colors of ...


2

What are they and how could I remove them on Photoshop? That's called moiré -- it's similar to what you see on TV when someone wears a shirt or tie with narrow stripes that seem to vibrate. If you search for something like remove moire in photoshop you'll find plenty of articles with advice for removing. Here's one from photographylife.com.. An alternative ...


2

Your ways are: using any film to record images instead of digital technology using the camera with strong enough AA filter using the camera with surplus of resolution (medium format cameras, may be very expensive) using very tight aperture (big F number) so that image is blurred enough with diffraction for moire to disappear. 1,5x crop camera with F13 will ...


2

There is a tool in Adobe Camera Raw specifically for fixing moire. In case you are not familiar, ACR comes with PS and Lightroom.


2

In general, it is not possible to reliably remove moire once it has been captured by the sensor. That's why the correct way to handle the problem is the blurring filter placed before the sensor. In the real life, however, high megapixel cameras can often get rid of the filter because the image is not going to be perfectly sharp anyway. The "technology" here ...


2

Moire is one form of "aliasing", which is false detail artifacts created by digital sampling at lower resolution than is necessary to accurately and adequately reproduce the smallest level of detail present. Better lenses have provided a bit finer image detail than the past sensor sampling could resolve accurately, causing this false aliasing (including ...


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