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Comments on the two reply posts.
First, I suspect that the Sony does NOT demodulate the NTSC
and then digitize it! I suspect ... but have heard that sets do this ...
it digitizes the IF somewhat undersampled (i.e. for a 45 MHz IF,
at say 15 MHz), just as it would do for ATSC, and use a DSP to
find and phase lock the carrier(s) and then demodulate them
digitally. In fact, whether in fact it does that really is the question!
As to analog/digital differences in quality ... 256 level is absolutely
enough for TV, zero quibble, given the gamma used. And a test
DVD (HDTV that is, even if not Blu-ray) is going to have an absolutely
great super-high bitrate that is going to show no banding ... and this one
does not show bands. The information content of these test discs is very very low indeed! Remember that except for motion patterns there is ZERO
interpolation to do between A and B frames! All the bits can be
put in those A and B frames.
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