Flickering railings and windows in Video shots

3 replies [Last post]
Joined: Mar 23 2005

I have a Panasonic HDC-SD 700 Camcorder which takes very good video, which I edit with Mac i-Movie 09. My disappointment is that if a shot includes railings or windows , these "flicker" . Obviously the "flickering" is a distraction from the rest of the scene.Does anyone know what causes this? And how it can be avoided?
I would add that the Panasonic is not alone in this. My previous camcorder, a Canon HV 20 produced exactly the same annoyance.

Alan Roberts
Alan Roberts's picture
Joined: May 3 1999

Almost certainly, the camera does not have the essential optical low-pass filter that would eliminate the higher spatial frequencies that cause aliasing when they move. All high-end cameras have such filters, but few cheap ones do.

You can't really avoid it, except by avoiding shots in which it happens. Keeping the depth of field short will help, because it puts backgrounds out of focus, but that would be hard in such a small camera.

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Joined: Jun 16 2006

Presumably you are converting the original footage to AIC in imovie?
Does the 'aliasing' you describe appear as bad on the original footage,or is it worse on the AIC imovie files?
As Alan says, there's little you can do to overcome aliasing on the original without optical filtering, but some versions of the AIC codec are reported to make the problem worse.
If so, then converting to ProRes would probably be a better option, for mac editing.

Joined: Jan 13 2007

Try De-Interlace effects with those shots.