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Comment by greiskul | Hacker News Reader

"Digital files need to be regularly transferred, putting them at greater risk of being damaged."

Wait, this doesn't make any sense to me, isn't much easier to make a backup of a digital file compared to an analog movie? The digital file can be replicated any number of times with no loss of fidelity, and can be transported on the internet. How is film a better preservation strategy?

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IIRC there's actually quite a bit of overhead and risk when doing digital storage on spinning or tape storage. Properly prepared and stored film will last quite a long time and often what degradation there is follows a known pattern. Replicating many times can be destructive to film but if archival is your goal, you do it a limited number of times and almost certainly have digital backups as well.

Except when ten years have passed and everyone's forgotten about the movie and tending its backups. Corruption happens, then it's too late. If you have a film print in a vault, it can be ignored or forgotten for decades and there's still hope.

Every large studio will have an archive department whose sole job is to protect the integrity of these films. They won't just 'forget' about a movie that's been placed into the archive system.

Oh yes they will - not least because digital archival is quite a bit more expensive than print archival, but doesn't generate much revenue, so guess who gets the shitty end of the stick in times of squeezed budgets? Also, while big studios can afford to invest in that sort of thing, lots of high-quality films originate outside big studios, where there's even less awareness of or capital for proper digital archival. In quite a few smaller studios the archive consists of disconnected disk arrays sitting in a box, a collection of LTO tapes, and a print master.

Anyone have any ballpark numbers on how the finished products are saved? Quick estimation of RED 4K at a _minute_ is about 2.5TB [1]. The file-vaults of studios then will eventually rival the NSA's data collection warehouse!

[1] http://www.hdslr-cinema.com/tools/filesize.php?w=4096&h=2304...

From a recent IEEE Spectrum article: "If you were to make a 2-hour motion picture with an extended color range in 4K and at 48 frames per second, the raw (uncompressed) movie file would occupy more than 15 terabytes. For comparison, the total amount of data in all of the e-mails sent in the United States in one year has been estimated to be 10.6 TB." http://spectrum.ieee.org/consumer-electronics/audiovideo/las...

The email estimation seems off by several orders of magnitude. If you follow the link in the IEEE article, you get this:

> It's estimated that the average size of an email is 75 kilobytes. Say we decide that 75 kb average is way off the mark and bump it up to 200 kilobytes per email times 144.8 billion emails per day times 365 days per year and were at just under 10.6 terabytes per year (3 of those Seagate drives will do the trick).

But doing that math myself results in:

   200 000  *  144 800 000 000  *  365  =  1.05 * 10^19

In other words, 10 exabytes. 1,000,000 times more than 10 TB. So, 3,000,000 Seagate drives, not 3.

Uhm... so? 15 TB of storage cost way under $1k.

Out of the camera is more like 6 GB/min [1] and DCI is limited to ~2 GB/min [2]. Those are both lossy; lossless masters would be much larger but it's questionable whether they need to be preserved.

[1] http://www.red.com/tools/recording-time

[2] http://en.wikipedia.org/wiki/Digital_Cinema_Initiatives

Well, the data for the final master copy is measured in terabtes but when you add up all the ingredients (unusued footage, VFX intercopies, safety copies, multi-layered VFX and audio stuff) a sci-fi blockbuster can hit a petabyte, easy.

I don't really get the every bit is precious thing when archiving film. Take the movie Casablanca, for example. Why would anyone care about more than the final cut, plus a few outtakes and screen tests? What's so precious about a blizzard of minute detail?

Well, suppose the master is damaged, and you need to go back to the original footage and reconstruct the scene using the same post-production methods that were available then? alternatively, suppose business conditions or personal conflict led to a truncated version of the original film being released, but the source materials allow the reconstruction of the director/ screenwriter/ producer's original vision?

The former has been the case with Fritz Lang's film Metropolis, with the complete version available today being a built (IIRC) from a mix of different masters and some raw footage, and the latter has been the case for another silent classic, Erich von Stroheim's Greed, which is a historical masterpiece but was heavily cut at release for both content and runtime. More recently, the version of The Good The Bad and The Ugly you get on DVDs now restores 19 minutes that were cut from the original...and I could cite a bunch of other important films (at least, if you're a film nerd) that only exist in their current form because someone knew the release version was compromised and went looking for the original production footage.

But they do. When I was in the business, many a story was written about some old editor dying and they find the original and only negative in a closet in his house.

When it comes to film prints it is probably better if they are ignored and not meddled with. The history of the Star Wars prints (http://arstechnica.com/business/2010/05/star-wars/) shows weaknesses of both analog and digital.

Edit: more about that http://arstechnica.com/gadgets/2014/05/could-disney-finally-...

Of course, you can also produce the movie in digital (to save cost and for convenience), then make a few film transfers as an extra archival backup.

I had the same thought: you can always shoot digital and make a film transfer; unless, of course, the only company making movie film goes under…

Digital movies MUST be transferred or you might lose it to "bit rot". The only thing you need to view an analog, film movie is light.

Not necessarily. Long term archival of data is hard and expensive to do... Storing stuff is easy, retrieval not so much.

I've heard of cases where 25 year old data stored in disk was corrupted over the years and had to be retrieved. In one case, somebody "lost" records of a few million bucks of receivables due to a bitched system migration.

sure it is, but you try opening up a word processor or spreadsheet file last saved in 1991 - it might not be corrupt, but there's a good chance that it won't come in properly. Likewise you have a floppy disk, hard disk, or CD-ROM from the same period you might have difficulty hooking it up - the CD-Rom is your best shot, but that assumes it was correctly encoded in the first place.

As in every other industry, film people tend to resist new technology, then stampede into it, then do the same thing with some other technology a few years later - we don't do backwards compatibility all that well (because there's not a whole lot of money in it) and while there are technical standards for everything from color space to perceived audio loudness, they are frequently slightly abused or subverted for artistic or budgetary reasons.

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