Back in 2011, Brian and Roger did an interview on BBC talking about the release of the Days of Our Lives documentary. At the beginning, they mention about a top of the pops performance that was wiped out which luckily someone they knew caught it on tape. Not sure which performance they're talking about but I'm guessing either SSoR from March 28th or Killer Queen from Nov. 11th, 1974. What makes me wonder is that for the bluray release, how and what such machine did they used to scale the tape to such HQ since the same tape containing the 11/11 performance surfaced on YT at its entirety without any upscaling or cropping?
Just because something is on Blu Ray it doesn't automatically mean it is in high quality or 'HD'. Blu Ray is simply a storage medium, the same as DVD, cassette, vinyl, an old shoe box......whilst Blur Ray can handle and present HD format material which DVD can't, it can also hold video and audio that standard definition or lower.
Upscaling works by either blurring or duplicating lines of resolution, the picture will not gain any new information, but will be stretched and filtered to fit a new aspect ratio.
All home Bluray players do this when you put a DVD into them.
In the 70's the BBC were recording on to tapes with 650 lines of resolution, much higher than home video recorders of the time (it's almost that of DVD's which is why DVD's were a massive upgrade even if shows were recorded on video).
If you think there is some magical technology involved, since only a second hand copy survived, then you are wrong twice.
Don't believe that "luckily someone they knew caught it on tape", as if someone recorded it from the living room TV with one hand while with the other was adjusting the antenna the get the best signal.
They (in fact one of their minions) probably found a TV station pro copy, an U-matic maybe, almost as good as the original open reel video tape.
It was enough for Brian almighty to make a biblical story out of it - "for it was lost but now is found".
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