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Is it a common issue on canon 60d to have moire & aliasing issue when recording videos. Or is it that my sensor or lens has a defect? I'm using the kit lens EF-S 18-135mm IS.

Does anyone here have this issue?

Turning down sharpenss & contrast didn't help.

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2 Answers 2

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Aliasing (and therefore moire, a type of aliasing) is a problem for almost all Canon DLSRs (as well as other manufacturers). The root cause is line skipping, whereby in order to get the necessary framerate only every third line of pixels is read from the chip.

If you have fine detail that is about the same size as a line of pixels then as the camera moves the detail will pop in and out of existence as it passes each active line of pixels.

The latest generation of sensors to be found in the 1DX and 5D mkIII apparently address this issue by reading the whole sensor and downsampling in order to produce the 1080p image.

The issue can be remedied to an extend by mounting an anti-aliasing filter (much stronger than the one in front of the sensor) on the lens. This blurs the image so that the detail will be spread over several lines, and not pop in and out as it crosses an active line of pixels.

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I can confirm the 5D mkIII has improved video to fix this moire issue thanks to its DIGIC 5+ processor. –  Mike Mar 18 '12 at 22:53
    
gotta have 5D mk3 after 10 yrs =) –  Petrick Lim Mar 19 '12 at 8:15

Moire patterns are ancient. They pre-date digital cameras by 100 or more years. They are caused when there is a small size difference between the pattern of the object and the pattern of the sensor, screen, etc.

You see them on commercial TV, typically on a news show or a talking-heads show where the guest wears a houndstooth jacket or some other cloth with a strong pattern. The solution is simple: make the guest change clothes.

Its is 99% the case that this is not a problem with your gear.

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thank you Pat =) –  Petrick Lim Mar 22 '12 at 8:38

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