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  1. Member
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    Just something I was thinking about. Betacam runs the tape at something like five to six times faster than traditional Beta in order to get 300 lines of video with 120 lines of component color. But you get a short runtime per tape as a result.
    W-VHS on the other hand is able to give you two hours of standard VHS-like runtime but with an HD signal and also component color.

    I learned from digital video that if you take a 1080p resolution 4:2:0 video you can get a 4:4:4 480p video out of it. I'm guessing analog video might work differently in that regard.

    I guess my question is, would you be better off with W-VHS than Betacam if looking for both higher quality and longer record time, if hypothetically speaking, both had been available in 1982 when Betacam launched?
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  2. Member Cornucopia's Avatar
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    You have got some numbers wrong.

    Both are component analog signals.
    Betacam (82) records (vertical resolution) exactly 525 iines NTSC or 625 lines PAL, and its signal is continuous. That means its limit of resolution is down to the filtering in the camera's & recorder's electronics. They say (in that wikipedia article) the "effective" horizontal resolution is 300 lines (with Beta SP being 340), but I can tell you from experience that it is more than that - more like 550-600.
    The difference is that the limit used in those web calculations always refers to the 4.2MHz bandwidth limitation of BROADCAST NTSC. However, component recording formats do NOT have that limitation yet. They are UPSTREAM of the the transmitter (with a Luminance bandwidth of ~6.4MHz, IIRC), and since they are not (usually) "broadcasted" to their recorders, so the bandwidth being recorded is higher that what actually will end up going out via the TV transmitter. And the equivalent chrominance is ~5.7MHz, so also much higher than previously stated. All of that was limited by what the available cameras of the day were able to provide, which was often the limiting factor.

    W-VHS has a number of improvements in technology due to being designed 11 years later, which Betacam doesn't have: higher density metal particle tape, time-compression integration allowing double data throughput, dual R/P heads allowing 2 tracks' worth of data to be stored simultaneously (doubling the throughput again), & advanced crosstalk cancellation. That, plus a higher speed than consumer VHS does allow for analog HD (1035/1125) to be recorded. However, it also cost ~ double what Beta/SP cost (recorder vs. recorder). That, plus the fact that it used the MUSE system which didn't catch on beyond Japan, also means that it wasn't near as compatible with existing systems (which were VERY predominantly still SD through the 90s).
    W-VHS did have a record time of ~107 minutes vs. 31 minutes of Beta, but that is also not 120+ minutes either. But for pros (the only folks who were buying either of these devices) tape runtime was not a deciding factor. Also, Beta was designed for mobile acquisition. W-VHS was not.

    There was a very good reason BetaSP was the king of analog SD, and it continued to be popular even well into the HD & Digital revolutions.

    Apples vs Oranges.

    Scott
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    Thank you so much for your feedback. That's all satisfying to my curiosity. I never worked with Betacam since I didn't get into video production professionally until the early 00s. Even then I was on the lower end of the market using DV/HDV at the time. But I remember these pro formats (not W-VHS) growing up in the 80s/90s.

    I would assume there has to be an upper limit to Betacam as well though, aside from the cameras/decks used, since I assume the tapestock had a maximum signal limit it could hold. Even for really nice metal particle tape. But I don't know.

    I was just curious if cost was no factor and both formats dropped into 1982 with both cams and decks available, which would have been preferred.
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  4. Member Cornucopia's Avatar
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    Limit of BetaSP was like equivalent to 600x480/576, with ~50dB SNR.
    None of the analog formats except Hi8, IIRC, used metal particle tape. Metal didn't really appear on analog videotape until late 80s (metal started in early/mid80s with analog audiotape first), and by that time of late 80s most of the other analog formats had been established. It did get used for a number of digital tape formats, though.

    I am intimately familiar with Beta/SP and its pros and cons, but have only had sporadic use with W-VHS. My memory is that W-VHS didn't hold up as well with artifacts and with multiple generations. Remember, any time you incorporate some form of compression (be it digital bitrate reduction, analog dynamic range compression, or time domain compression), and anytime you decrease analog areal recording density & speed per bandwidth, you are making compromises and the signal is - for lack of a better term - more fragile. So, I would say BCSP was very robust, and WVHS less so, but both are head & shoulders above your consumer formats like vhs & betamax, and even Umatic.
    Looking strictly at resolution, of course an HD signal has the lead over an SD signal. But those formats had other parameters to gauge them by, and I would say that it wasn't until digital hit its stride and digital compression went through a few generations, before HD (often in the form of HDCAM) was hands down 100% better all the time over SD, using all those metrics. That was around 2001/2002. So the safe bet in the 80s and early 90s would have been Beta, BetaSP.


    Scott
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  5. Capturing Memories dellsam34's Avatar
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    Professionals usually go for a reliable and well supported format, Betacam delivered that. W-VHS was more of like IMAX for film, It wasn't built around mobility and speed, The camera's are oversized and are suitable for studio or steady shooting, Also the cost is another factor, Studios main goal is to get the news delivered, HD wasn't that important to them.
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    Originally Posted by Cornucopia View Post
    Limit of BetaSP was like equivalent to 600x480/576, with ~50dB SNR.
    None of the analog formats except Hi8, IIRC, used metal particle tape. Metal didn't really appear on analog videotape until late 80s (metal started in early/mid80s with analog audiotape first), and by that time of late 80s most of the other analog formats had been established. It did get used for a number of digital tape formats, though.

    I am intimately familiar with Beta/SP and its pros and cons, but have only had sporadic use with W-VHS. My memory is that W-VHS didn't hold up as well with artifacts and with multiple generations. Remember, any time you incorporate some form of compression (be it digital bitrate reduction, analog dynamic range compression, or time domain compression), and anytime you decrease analog areal recording density & speed per bandwidth, you are making compromises and the signal is - for lack of a better term - more fragile. So, I would say BCSP was very robust, and WVHS less so, but both are head & shoulders above your consumer formats like vhs & betamax, and even Umatic.
    Looking strictly at resolution, of course an HD signal has the lead over an SD signal. But those formats had other parameters to gauge them by, and I would say that it wasn't until digital hit its stride and digital compression went through a few generations, before HD (often in the form of HDCAM) was hands down 100% better all the time over SD, using all those metrics. That was around 2001/2002. So the safe bet in the 80s and early 90s would have been Beta, BetaSP.


    Scott
    Again. Thank you for your reply. Super helpful.

    It is interesting. If digital had taken longer, I wonder if we would have seen W-VHS or something like it mature into more of a professional analog HD system. I know Sony also had their HDVS.

    I don't know if it's just nostalgia or what, having grown up with VHS, Video8, and to some degree Betamax, and Laserdisc, but I've become interested in the analog video formats again. My friends and I used to cut our teeth on VHS and Video8 camcorders shooting little stop motion animation movies and live action horror and comedy movies back in the 90s before I bought a TRV900 in 1999 and started shooting DV. So it reminds me of my youth. Of course back then I hated the look because it wasn't film. It didn't look like a proper movie but like a soap opera. These days I go out of my way to find old SoV (Shot-on-Video) movies from the 80s and 90s. Funny how perspective can change over time. Lol.

    Just out of curiosity, kind of a stray thought since you brought up digital compression, but I wonder what the actual bitrate of VHS would be, if it had been digital back in 1977. I've heard estimates that a VHS tape could hold the digital equal of anywhere from 2GBs to 8GBs, with D-VHS tapes holding 50GBs. But they used higher end tape. I'm just talking straight 1977 VHS. I think knowing the digital capacity of that would give a better idea of the kind of bitrates a digital equivalent would be at different speed. Even if we are talking apples to oranges.

    it's something I've been thinking about since I've been transferring some old VHS tapes to DVD these past couple days. I'm surprised at how good they look on my 55" 4K TV. I was expecting an absolute mess on the big screen. Granted they are being scaled up through my DVD-recorder and sent out of its HDMI port. But I've done tests in the past on my computer where I've converted DVDs to 352x480 resolution mp4s (just to see the results), and unless the bitrate is high enough like that of DVD, it's not looking anywhere near as good as the VHS tapes do on my big screen. They are blocky/pixelated versus the softer noisy VHS, which I think I prefer. It seems less distracting. But if you have to use bitrates as high as DVD to get rid of the pixelation, you might as well be using a full D1 resolution instead of half. It appears less pixelated it seems. So I can never seem to find a valid use for half D1. With that considered.
    Anyway, like I said, just a stray thought.
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    Originally Posted by dellsam34 View Post
    Professionals usually go for a reliable and well supported format, Betacam delivered that. W-VHS was more of like IMAX for film, It wasn't built around mobility and speed, The camera's are oversized and are suitable for studio or steady shooting, Also the cost is another factor, Studios main goal is to get the news delivered, HD wasn't that important to them.
    Yeah I can definitely understand that.
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  8. Member Cornucopia's Avatar
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    I think you are seeing it through the lens of nostalgia.

    VHS & Beta and V8 was, and is, for lack of a better term, poor. I won't say crap (although looking at 3rd gen home-recorded SLP, is could very well be). Those consumer formats never even achieved the capability that SD was capable of (C-format & Laserdisc being the best composite analog versions and Betacam/SP & MII being the best component analog versions, and D2 and D1 being the best uncompressed digital versions respectively).

    The problem with digital has always been HOW MUCH BITRATE IS GOOD ENOUGH? (good enough for WHO?, WHEN?) And back when digital consumer video formats were just getting popular (late 90s, early 2000s), what was "good enough" then is embarrassingly mediocre today. So many folks undercut themselves in the name of small size/quick transfer that those old digital copies with their excessive artifacts don't hold up as well, in fact even as well as standard analog degradation does. Folks here were/are guilty of it all the time, even in today's streaming-heavy era.

    But I for one have little nostalgia for either of those - my bar is high and I want the best, regardless of format, so it's a little easier to be objective when evaluating.
    Here's an example that I've mentioned on this forum before: guitar virtuoso Ry Cooder's "Bop Til you Drop" album came out in 1979, and it had the notoriety of being one of the first non-classical albums that was full D-D-D recording chain. And though the digital technology wasn't even as good then as it will have been a few years, or decades, later, the engineers were adamant at getting the best possible quality out of it, and made sure to eek out every bit of dynamic range available while maintaining proper dithered processes all along the way. And it shows - listen to "The Very Thing that Makes Her Rich (will make you Poor)". I describe it as "silky" and "scintillating", with NO background hiss, just the "natural" studio-produced reverb. And well produced analog recordings of that era simply did NOT sound anywhere near to what this did. Which is why digital recording exploded in the ensuing era.
    Now, I've heard this recording on multiple formats - original LP, FM radio, cassette, CD, mp3, SACD, streaming (Spotify/aac). It's easy to order the quality: 1st is SACD, then CD (superbitmapped), regular CD, LP, aac, mp3, FM radio, cassette. Notice how both analog & digital are in the mix, but well-crafted digital still is top dog.

    The same can be said on the video side of the difference between (well-produced) VHS, vs D1 or even DVD. When factors of inadequate efforts & production choices are factored out...it's not even close. I would go hands down with DVD (since I have almost no access to true D1 material any more) every time. That doesn't even take into consideration the extra features and the convenience factor.

    I'm not going to dwell much on "what if"'s with regard to bitrates expected of vhs. If you want to get a reasonable guess, you could look at what LTO and similar data backup tapes have been throughout the years (since it happens to also be 1/2" magnetic tape). Not counting its many precursors of lower capability, when LTO1 came out in 2000, it read/wrote ~160mb/sec with a total of 100GB per tape. VHS in comparision had a much slower tape speed but countered that with the helical scanning, so it probably was equivalent, and would likely not have the advanced track-writing capability that LTO had, and while LTO tapes were 607meters, your usual T-120vhs tape was 247 meters, so 2/5 the size, making that equivalent to ~40GB. That's using 2000-era technology, not 1976 era. That's about as much as I am going to speculate.


    Scott
    Last edited by Cornucopia; 13th Jun 2024 at 08:13.
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