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

Removing Moiré from Scans When Your Scanner Doesn't Have Descreen

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Moiré Reduction

Bore and after moiré reduction. | View Larger

© S. Chastain (Source: 'The Birth of Venus' by Botticelli) Moiré detail

Moiré detail | View Larger

© S. Chastain (Source: 'The Birth of Venus' by Botticelli) Moiré examples

Moiré resulting from a scan from a newspaper (top) and a book (bottom).

© S. Chastain

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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