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Post by nathangeorge on Aug 30, 2023 5:12:11 GMT
I vaguely recall hearing something on the radio a few years ago about a massive BBC project to upload archive content to some kind of giant cloud. If I remember rightly, the project started with educational / research material with music being the next priority. So my question, how safe are digital archives / repositories?
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Post by garygraham on Aug 30, 2023 5:26:02 GMT
" The DVD bitrate and compression can't even get close to being an identical copy even of a 40-year-old VHS tape. And a VHS tape is not the same as a broadcast tape. " A computer encode of a VHS tape would be as good as the original if encoded properly. Same for a broadcast tape. You don't lose anything. All these older formats (Umatic for example) are much lower resolution that today's HD world - so nothing is lost if recorded properly. A computer can very well do its part for preservation - but it does ultimately depend on what you're playing it on. My biggest headache trying to preserve VHS (as an example) is being able to find a VHS player that's up to scratch in this day and age, without spending a small fortune and forking out for a time base corrector. In short, the DVD bitrate is much higher than any of these old formats - meaning it can capture them perfectly, if you know what you're doing. But what does "encoded properly" mean? I encode VHS and S-VHS to digital all the time. Some of my home encoded shots have even been shown on TV. If the encoding is uncompressed then yes the digital file will be identical to the VHS. But the file size will be about 500Mb per minute and only about 9 minutes of video will fit onto a DVD disc as data. DVD is MPEG2 encoding. I believe the BBC uses a bitrate of around 50 Mbit/s for archival material in MPEG2 format. Whereas best quality on a DVD is only 9.80 Mbit/s. That isn't the whole story either because archival video is encoded with all iframes which increases quality but also the filesize. Lossy (compressed) formats such as MPEG2 or MP4 give an illusion of quality. They throw away data that is less likely to be noticed and they smooth the picture. If uncompressed can't be used, I've found the best compression for VHS is still the MJPEG codec. That works out at about 22.5 minutes on a data DVD. The bitrate for this episode of Vision On on YouTube is about 1Mbit/s! It is effectively encoded at 640x480 whereas the original programme would have been 768x576. The frame rate is at 25 frames per second instead of the 50 fields interlaced original. However it's a telecine anyway which is only 25fps. This is all vastly inferior to the original 2 inch broadcast tape. www.youtube.com/watch?v=KBWJ8TqJxL0
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Post by garygraham on Aug 30, 2023 5:37:05 GMT
From what heard the BBC digitisation project produced 2 D3 tapes of each 2" tapes, which I assume are stored in different places, as well as the original tapes being donated to the BFI. And then Panasonic discontinued the D3 video format and some years ago the BBC found it didn't have enough video head time left to digitise all the D3 tapes. What happened? It isn't clear. There has been talk about D3 tapes being "selected for preservation". Is it only duplicates that haven't been copied or is unique material being left to die on the "non-selected" D3 tapes? What I find extraordinary is that the BBC wasted £98m on its failed Digital Media Initiative (know as "Don't Mention It" at the BBC). Why not offer Panasonic a few millions to make some extra D3 video heads? Or perhaps they did and Panasonic said no? Migrating to half inch tape formats and ditching two inch and one inch masters was a mistake. And choosing D3 was an even bigger mistake. This is why there are so many tape drop outs in archive programmes. It was known that these metal based tape formats were problematic more than 30 years ago. I'm not completely up-to-date but last I heard the BBC was migrating video to LTO data tape. Although the tape is believed to have a life of up to 30 years, again this depends on equipment continuing to be available. to play the tapes. It may be that tapes need to be migrated after just 15 years. It seems unlikely that TV companies will be able to migrate their entire archive of LTO tapes onto the latest format every 15 years. Many hundreds of thousands of tapes in the case of the BBC... And of course many organisations aren't even migrating material off obsolete videotapes as they can't afford it. So people are right to be concerned.
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Post by sonnybh on Aug 30, 2023 20:31:02 GMT
From what heard the BBC digitisation project produced 2 D3 tapes of each 2" tapes, which I assume are stored in different places, as well as the original tapes being donated to the BFI. And then Panasonic discontinued the D3 video format and some years ago the BBC found it didn't have enough video head time left to digitise all the D3 tapes. What happened? It isn't clear. There has been talk about D3 tapes being "selected for preservation". Is it only duplicates that haven't been copied or is unique material being left to die on the "non-selected" D3 tapes? What I find extraordinary is that the BBC wasted £98m on its failed Digital Media Initiative (know as "Don't Mention It" at the BBC). Why not offer Panasonic a few millions to make some extra D3 video heads? Or perhaps they did and Panasonic said no? Migrating to half inch tape formats and ditching two inch and one inch masters was a mistake. And choosing D3 was an even bigger mistake. This is why there are so many tape drop outs in archive programmes. It was known that these metal based tape formats were problematic more than 30 years ago. I'm not completely up-to-date but last I heard the BBC was migrating video to LTO data tape. Although the tape is believed to have a life of up to 30 years, again this depends on equipment continuing to be available. to play the tapes. It may be that tapes need to be migrated after just 15 years. It seems unlikely that TV companies will be able to migrate their entire archive of LTO tapes onto the latest format every 15 years. Many hundreds of thousands of tapes in the case of the BBC... And of course many organisations aren't even migrating material off obsolete videotapes as they can't afford it. So people are right to be concerned. I heard the BBC were caught out by D3 being discontinued.
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John Wall
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Post by John Wall on Aug 31, 2023 23:06:12 GMT
The technical side of preservation - without the presentists hacking things about - is very difficult, as has been expounded above.
Interestingly older material is easiest. Photography developed, no pun intended!, in the 19th century as did, silent, movies. It’s extremely easy to retrieve the signal from the medium and if the material is stored properly the signal can be easily retrieved in the future. Sound movies are early 20th century and, again, relatively simple technology. I understand that Hollywood are “saving” movies on 35mm.
The difficulties with the various tape formats have been well, and frighteningly, detailed above.
In terms of digitisation memory isn’t really a problem as there almost seems to be an infinite amount now available. I believe that movies are now distributed electronically, how much memory does a couple of hours 4k movie consume?
The “cloud” is actually servers in various parts of the world meaning that things can be stored in multiple locations. What then matters is the ability to decode the information which is another matter. Some preserve programs but these are invariably linked to operating systems. Will it be possible to play mpegs in 100 years time?
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Post by garygraham on Sept 3, 2023 11:03:32 GMT
The technical side of preservation - without the presentists hacking things about - is very difficult, as has been expounded above. Interestingly older material is easiest. Photography developed, no pun intended!, in the 19th century as did, silent, movies. It’s extremely easy to retrieve the signal from the medium and if the material is stored properly the signal can be easily retrieved in the future. Sound movies are early 20th century and, again, relatively simple technology. I understand that Hollywood are “saving” movies on 35mm. The difficulties with the various tape formats have been well, and frighteningly, detailed above. In terms of digitisation memory isn’t really a problem as there almost seems to be an infinite amount now available. I believe that movies are now distributed electronically, how much memory does a couple of hours 4k movie consume? The “cloud” is actually servers in various parts of the world meaning that things can be stored in multiple locations. What then matters is the ability to decode the information which is another matter. Some preserve programs but these are invariably linked to operating systems. Will it be possible to play mpegs in 100 years time? I wonder what impact a solar flare would have on servers? I'm still a fan of BD-R data discs with one copy of some things on hard drive too. It's no wonder the BBC has gone for data tape. It's still a great way to store masses of data. When you think how much is on even a 40-year-old VHS tape.
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John Wall
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Post by John Wall on Sept 3, 2023 12:47:49 GMT
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Post by richardwoods on Sept 9, 2023 17:09:57 GMT
Well, if archive TV was still produced and sold to the public in hard copy such as DVD & Blu-Ray then I would feel a lot happier with the reduced risk of loss offered by multiple high quality copies being out there. I think we are in danger with the move towards streaming as pretty much the only way to view old programs of losing more historic material as we are potentially finding ourselves back in the pre home recording era, and we all know how well that went with centralised archiving. In addition we have the issue of perceived unsuitability of material by some and all that entails. Potentially we could be heading in to quite a high risk time for old material.
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Post by garygraham on Sept 9, 2023 18:28:11 GMT
Well, if archive TV was still produced and sold to the public in hard copy such as DVD & Blu-Ray then I would feel a lot happier with the reduced risk of loss offered by multiple high quality copies being out there. I think we are in danger with the move towards streaming as pretty much the only way to view old programs of losing more historic material as we are potentially finding ourselves back in the pre home recording era, and we all know how well that went with centralised archiving. In addition we have the issue of perceived unsuitability of material by some and all that entails. Potentially we could be heading in to quite a high risk time for old material. I definitely think we're heading into a risky time. With organisations such as the BBC under financial pressure perhaps. Storage isn't the only cost. Staff have to oversee any migration and update records. And often for material that has no foreseeable financial benefit. Whatever our view, surely no one can dispute that "cancel culture" has reduced or even eliminated the chance to earn an income from numerous old programmes and films. Some aren't shown at all. Others just as clips. Editing time to remove "unacceptable" bits is another cost. More widely, the younger generation hasn't been encouraged to consume old TV and films in the way we were in the past. Many don't want to, for fear of what they might see. So that has reduced the market. Some of the most mainstream, popular shows from 40, 30, even 15 years ago contain material that will have the Twittersphere shrieking in horror now. Nearly everything I watch from my collection of VHS tapes has something. Even cuddly shows such as Victoria Wood ("bras for men"). I don't think people realise just how much is quietly being snipped out. Recently I noticed the final gag on the first episode of Man About the House on ITVX has gone.
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John Wall
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Post by John Wall on Sept 9, 2023 18:37:09 GMT
👆 There are quite a lot of stereotypical “dumb women” in shows that are relatively recent. Has any Les Dawson with his mother in law gags been shown recently? Mike Yarwood has just died, he was massive 40-45-50 years ago, will we get any repeats?
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Post by garygraham on Sept 9, 2023 19:14:44 GMT
👆 There are quite a lot of stereotypical “dumb women” in shows that are relatively recent. Has any Les Dawson with his mother in law gags been shown recently? Mike Yarwood has just died, he was massive 40-45-50 years ago, will we get any repeats? My friend and I joke that we're like the men in "The Worm That Turned"on The Two Ronnies. Gathering in secret to watch forbidden films and TV. Expect we're not the ones dressed as women. Talking of which, surely drag and the Carry On films can't survive much longer if this continues? The BBC has succeeded in alienating older viewers while at the same time younger aren't tuning in. In the past it was older viewers who brought along younger to BBC services to an extent. I can't see broadcast TV surviving in its current form.
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Post by John Wall on Sept 9, 2023 19:18:58 GMT
TPTV have just shown Fireball XL5, Venus was very much a 1962/63 woman.
They’re now onto Thunderbirds and Lady Penelope is a vast improvement but Tin Tin and Grandma aren’t up to much and the Hood is a slant eyed Asian baddie.
However, those shows were made without blue screen, green screen, CGI or whatever and are still great 👍
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Post by garygraham on Sept 9, 2023 22:49:02 GMT
TPTV have just shown Fireball XL5, Venus was very much a 1962/63 woman. They’re now onto Thunderbirds and Lady Penelope is a vast improvement but Tin Tin and Grandma aren’t up to much and the Hood is a slant eyed Asian baddie. However, those shows were made without blue screen, green screen, CGI or whatever and are still great 👍 Good production values and HD quality thanks to 35mm film (and bright lighting?).
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John Wall
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Post by John Wall on Sept 10, 2023 7:45:19 GMT
TPTV have just shown Fireball XL5, Venus was very much a 1962/63 woman. They’re now onto Thunderbirds and Lady Penelope is a vast improvement but Tin Tin and Grandma aren’t up to much and the Hood is a slant eyed Asian baddie. However, those shows were made without blue screen, green screen, CGI or whatever and are still great 👍 Good production values and HD quality thanks to 35mm film (and bright lighting?). Yep, they were early adopters of colour, with Stingray in, iirc, 1963/4 and Lew Grade bankrolled them.
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Post by garygraham on Sept 10, 2023 8:19:38 GMT
Good production values and HD quality thanks to 35mm film (and bright lighting?). Yep, they were early adopters of colour, with Stingray in, iirc, 1963/4 and Lew Grade bankrolled them. I wonder if lower speed, finer grained film was used too in the 1960s with brighter lighting? Perhaps the economic crisis of the 70s led to a reduction in light levels on set and the use of faster film?
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