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Here's a tip, drawn from a recent experience. Start recording from VHS after the "snow," since it might wreak havoc on a DVD recorder's encoder.
A VHS tape originally recorded on a full size Hitachi video camera had a 5 or 10-second lead-in of snow (unrecorded tape) before the recording starts. My first attempt to record this, played on a Sony SLV-N71, to my DVDR resulted in the first five minutes or so of the recording being highly pixelated, like a low-quality VCD or a WMV at about 200 kbps. After that, it clears up and looks fine.
When I saw the result, I went on the hunch that the snow at the beginning of the tape sent the DVDR's encoder into a tizzy. I had set the bitrate on the recorder to 7.2 mbps, but even so, it looked terrible right after the snow. Just a wild guess here but perhaps these machines record with Variable Bit Rate, not Constant Bit Rate, so after allocating a peak bitrate to deal with the complex and constantly changing video pattern of the snow, the encoder was tired and shagged out after a long squawk and only allocated a really low bitrate thereafter, according to the law of averages.
This preceding bit of pseudoscientific speculation does raise an interesting question, though: Do DVDRs record in VBR or CBR?
Anywhiz, I recorded the exact same tape with the exact same bitrate (7.2 mbps) again, but this time starting after the snow, and all was fine.
A VHS tape originally recorded on a full size Hitachi video camera had a 5 or 10-second lead-in of snow (unrecorded tape) before the recording starts. My first attempt to record this, played on a Sony SLV-N71, to my DVDR resulted in the first five minutes or so of the recording being highly pixelated, like a low-quality VCD or a WMV at about 200 kbps. After that, it clears up and looks fine.
When I saw the result, I went on the hunch that the snow at the beginning of the tape sent the DVDR's encoder into a tizzy. I had set the bitrate on the recorder to 7.2 mbps, but even so, it looked terrible right after the snow. Just a wild guess here but perhaps these machines record with Variable Bit Rate, not Constant Bit Rate, so after allocating a peak bitrate to deal with the complex and constantly changing video pattern of the snow, the encoder was tired and shagged out after a long squawk and only allocated a really low bitrate thereafter, according to the law of averages.
This preceding bit of pseudoscientific speculation does raise an interesting question, though: Do DVDRs record in VBR or CBR?
Anywhiz, I recorded the exact same tape with the exact same bitrate (7.2 mbps) again, but this time starting after the snow, and all was fine.