Moiré patterns can appear on over-sharpened images, or on images with superimposed grids. The patterns will be formed when an image is taken, or when it is scanned, edited or printed.
A moiré pattern can be easily recognised if you enlarge the image (100% - 800%). As you can see in the following example, the image shows strong noises or over sharpening.
As our photo prints and photobooks are photographically printed, all the details in the images will become clear and distinct. As a result, the moiré pattern will also come into being during the process.
How to avoid moiré
In order to avoid the moiré effect, we would recommend you to blur the parts of an image that show the moiré pattern.
You can select the parts that were affected by the moiré patterns, or create a mask. Then you can apply the filter "Gaussian Blur". There is no standard criteria on how to adjust the settings. It depends on the image itself, its size and how strong the moiré pattern is.
After blurring the affected parts, you can enlarge the image once again (100% - 800%). The parts should be homogeneous and the moiré pattern should not be visible any more.
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