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Message: <blockquote data-quote="WayneF" data-source="post: 477214" data-attributes="member: 12496">Moire in the sensor is basically when the detail in the image (the size of the closely spaced stripes) are finer detail than the pixel spacing of the sensor can resolve.  Hence alaising, false detail that we call moire.Size depends on distance, stripes appear larger when up closer.Anti-aliasing filters on sensors just blur the image a little bit, not enough to much matter, but just a bit so to eliminate finer detail than the sensor cannot resolve, hence no alaising.  Today some 24 megapixel cameras are omitting the AA filter,  being assumed enough resolution, sufficient to not be a problem ... very often.  Not fail safe.How does the original size image look at 100% size?  See moire there?Resampling high resolution images to be smaller can in some cases cause moire, containing detail finer than the resampling of the smaller image can show.  In such cases, very slightly blurring the image (about the slightest amount) before resampling can prevent the moire. That blurring does not hurt anything, an image 1/8 the size only contains 1/8 the detail anyway.Also showing the image on the LCD monitor can in a few cases show moire, due to the matrix spacing of the screen.  As we zoom to change size, we might sometimes go through a zone that shows moire (a few images might).Probably the worst cases are when scanning magazine images (typically 150 dot per inch halftone images) with scan resolutions not exceeding the 150 dpi.  It really needs 2x or 4x sampling (300 dpi or 600 dpi) to prevent the moire then.</blockquote>

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