What is the name of the phenomenon where a repeating pattern on a photo is colorized in alternating stripes, like this?
In addition, does leading software like Photoshop and Lightroom have intelligent tools to combat/remove this phenomenon?
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Sign up to join this communityWhat is the name of the phenomenon where a repeating pattern on a photo is colorized in alternating stripes, like this?
In addition, does leading software like Photoshop and Lightroom have intelligent tools to combat/remove this phenomenon?
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.
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:
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