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by noipv4 1287 days ago
Coporation

BTW, what makes the pictures in the paper wildly dithered like that?
2 comments
re9 1287 days ago
Scanning printed material probably, newspaper photos are made of dots... Printing + scanning artifact -- https://www.scantips.com/basics06.html https://photo.stackexchange.com/questions/70139/what-caused-...
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rbanffy 1287 days ago
Also, how to fix it: https://www.getrevue.co/profile/shift-happens/issues/moire-n...
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re9 1287 days ago
Probably easier with ImageMagick: https://legacy.imagemagick.org/Usage/fourier/#noise_removal
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Maursault 1287 days ago
The original image was, of course, a photograph made from negative B&W film. For one color printing, the picture was halftoned[1] to simulate greyscale or continuous tone. When the reproduced halftone image was scanned, due to the scanning dpi, it created a moiré pattern.[2]

[1] https://en.wikipedia.org/wiki/Halftone

[2] https://en.wikipedia.org/wiki/Moiré_pattern

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