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Old 27th February 2006, 23:20   #9  |  Link
jmac698
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Quote:
there is no way that NTSC SD video has a Luma B/W of 13.5MHz.
From the capture guide:
This makes your final sample rate 704 samples / 52 µs = 13.54 MHz.

This is sample rate. According to the Nyquist theorem, you can record frequencies of half the sample rate, making the bandwidth 6.77MHz. Modern video DAC's have excellent filters and I expect to reach very near this value. If you read my post, I said rate, so while I was correct, I should have compared bandwidth MHz numbers together, I apologize for the mistake. In any case, the luma bandwidth is still greater, in one estimation (approx.), 6.77/3.57=1.88 times better.

Quote:
either grab the .ts file or rip it
this would be ideal, but not everyone has an HDTV/DVB card. Also, many satellite settop boxes don't even have firewire. The point, obviously, is to record from a hidef channel on a satellite box in better quality. I suspect the svideo signal itself is also partly to blame.

Anyhow, the technique is there for those who want to make use of it, as is the multiple cap technique to reduce noise. Judging from the forums, many of us are interested in ways of improving quality.
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