Field Phase Problem
I've read that PAL discs sometimes have a problem where the two fields
that make up each video frame somehow end up out of phase, so that
each video frame ends up as a combination of fields from two adjacent
film frames instead of coming from the same film frame. Such video
frames might be stored progressively on disc, but playback looks
horrible on progressive displays because each frame shows ghosting
effects at the edges of any motion.
The Rainbow Products disc from Australia has two places where this
happens: For the first 11 minutes, and another 26 minutes beginning at
about the 38 minute mark.
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Uncorrected video frame, the two video fields are from adjacent film frames.
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Corrected video frame, the two video fields are from the same film frame.
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