ErMaC wrote:Actually it's the area of the picture where on a VHS tape the Hi-Fi audio track is stored. You'll notice you don't see those lines on DVDs or LDs, but you do see it on VHS tapes. I don't remember offhand if SVHS has this problem but I believe it doesn't.
You don't see them on LDs because LDs do not use a pair of heads sweeping around a drum to read the disc, while VHS *does* - and the head that's come to the end of its sweep has to hand off to the other. But the tape is wrapped around slightly more than 180 degrees of the drum, so there's a little overlap. (I have a book somewhere; I may be misremembering.) DVDs, meanwhile, have nothing whatsoever to do with this analogue process. I *have* seen this changeover on notionally professional recordings - the Culture Q Connection on the Kizuna DVD - so I'm guessing Beta SP has the same mechanism, because I can't imagine why any D format, or Digibeta, would have the same issue.
As for the HiFi track - I thought that went directly under the picture information across the entire width of the tape, recorded by a separate pair of heads about 30 degrees or so ahead of the video heads?