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What is the name of the phenomenon where a repeating pattern on a photo is colorized in alternating stripes, like this?

enter image description here

In addition, does leading software like Photoshop and Lightroom have intelligent tools to combat/remove this phenomenon?

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  • \$\begingroup\$ Photoshop has a specific de-Moiré tool which works well on this. It's referred to in the link-only answer below & I'd rather that user came back & added a précis to their own answer than steal their thunder [& points]. i.stack.imgur.com/qTd9g.png \$\endgroup\$
    – Tetsujin
    Jun 17 at 16:02

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This is named moire. And happen when the angle of the camera is different by small amount to the pattern.

You can use for example this manual to remove it.

  • From the Photoshop Class folder, open file.

  • Go to View > 100%. He’s been scanned at 359 ppi, and as you can see, a strong dot pattern is evident.

  • First, go to Filter > Noise > Median.

  • Make the radius 2 pixels and click OK.

  • Next, go to Image > Image Size and reduce the image to 150 Pixels/Inch (ppi).

  • Click OK.

  • Finally, go to Filter > Sharpen and apply the Unsharp Mask filter. Try these settings: Amount: 50% Radius: 3 px Threshold: 5

  • Click OK.

Open the original and compare them side-by-side by choosing Window > Arrange > 2-up Vertical. Make sure they are both zoomed to 100%. The final image should have a much more natural texture than the original.

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This is a moiré effect. Not easy to remove, which is why cameras often have a low-pass filter in front of the sensor; this reduces the definition a bit but reduces the moiré. If you have the RAW file, demosaïcing apps can let you use a different demosaïcing algorithm that reduces the occurrence of moiré.

In this very case, just de-saturating the area a bit could be sufficient: enter image description here

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    \$\begingroup\$ While the color moiré was removed, the pattern moiré is still evident. \$\endgroup\$
    – scottbb ♦
    Jun 17 at 22:53
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Bonjour, this is called Moiré... Sometimes It is quite tricky to tackle despite the tools ... The best tutorial for you : https://photographylife.com/what-is-moire

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    \$\begingroup\$ While this link may answer the question, it is better to include the essential parts of the answer here and provide the link for reference. Link-only answers can become invalid if the linked page changes. \$\endgroup\$
    – Tetsujin
    Jun 17 at 15:36

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