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How To Remove Moire Patterns From Scanned Photos in Photoshop and Elements

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Moire Example

Moire example from an image scanned from a newspaper.

Scanning photos from books, magazines and newspapers often results in an unsightly interference pattern called moire. If your scanner doesn't offer descreening, it's not too hard to remove yourself.
Difficulty: Average
Time Required: 5 minutes

Here's How:

  1. Scan the image at a resolution approximately 150-200% higher than what you need for final output.
  2. Go to Filter > Noise > Median.
  3. Use a radius between 1-3. Typically the higher the quality of the source, the lower the radius can be. Use your own judgement, but you will probably find that 3 works well for newspapers, 2 for magazines, and 1 for books.
  4. Go to Image > Image Size (Image > Resize > Image Size in Elements) and resample to the desired image size and resolution using the bicubic resampling option.
  5. Make sure you are zoomed to 100% magnification.
  6. Go to Filter > Sharpen > Unsharp Mask.
  7. Exact settings will depend on the image resolution, but these settings are a good starting point: Amount 50-100%, Radius 1-3 pixels, Threshold 1-5. Use your eye as the final judge.

Tips:

  1. If you still see a pattern after applying the Median filter, try a slight gaussian blur before resampling. Apply just enough blur to reduce the pattern.
  2. If you notice halos or glows in the image after using Unsharp Mask, go to Edit > Fade. Use settings: 50% Opacity, Mode Luminosity. (Not available in Elements.)

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