Shelf Life of Digital Media vs Cost

[I-HEAR_YOU]

OK I see a lot of discussions of how wonderful the new digital age is with Compact Flash Cards, SD Cards, Hard Drives and many more formats for recording audio vs cost of Tape Formats,

Analogue tapes that were recorded 50 years ago still survive and yes they have lost a little oxide and need to be rejuvenated. But at the end of the day they still are usable.

CDs and DVDs that are recordable have a shelf life of ??

Hard Drives if left on the shelf will fail after 5 to 10 years unless fired up and run every 6 months or so.

We work in an industry that spend Millions of $ on production and complain about the cost of the most important part, the recording media!!

When you buy a recorder, do you buy the cheapest?? When you buy Radio Mics do you buy the cheapest??

So why buy Media that is cheap? Like buying cheap tyres for your expensive car. If it doesn't stay on the road it really doesn't matter how good the car is.

Quality costs. If the media fails does that not cost the production? In the good old days did we do backups of backups to be sure we wouldn't lose our recording??

We get more files on the new media. So we can lose more if they fail.

My question,who knows how long these Digital formats will survive? And is it really as good as tape??

Is it worth the cost ??

[RPSharman]

It's not about money for me.  I made more money "selling" DVD media to production than I do now without that revenue stream. To me it's about not using hundreds of DVDs and packaging.

We had the same discussion a while back about batteries and if the failure rate of rechargeables. Is it worth it?

I say 'yes' on both counts.

[soundslikejustin]

According to the "Care and Handling Guide for the Preservation of CDs and DVDs - A joint Council on Library and Information Resources (CLIR) and NIST project" guide,

"Among the manufacturers that have done testing, there is consensus that, under recommended storage conditions, CD-R, DVD-R, and DVD+R discs should have a life expectancy of 100 to 200 years or more; CD-RW, DVD-RW, DVD+RW, and DVD-RAM discs should have a life expectancy of 25 years or more. Little information is available for CD-ROM and DVD-ROM discs (including audio and video), resulting in an increased level of uncertainty for their life expectancy. Expectations vary from 20 to 100 years for these discs.

"Few, if any, life expectancy reports for these discs have been published

by independent laboratories. An accelerated aging study at NIST estimated the life expectancy of one type of DVD-R for authoring disc to be 30 years if stored at 25°C (77°F) and 50% relative humidity. This testing for R discs is in the preliminary stages, and much more needs to be done."

_____________________________

The guide also mentions that five years is the shelf life of unburned disks.

[I-HEAR_YOU]

I remember when DVDs first came out and they cost $15.00+. Now they cost $ .50c-.

Something has to give and I can't see how they are going to last 100 Years. Having watched them delaminate in tests!!

The issue is, is it really cost effective if you have to clone every so often and what do you lose by cloning??

[Marc Wielage]

"Among the manufacturers that have done testing, there is consensus that, under recommended storage conditions, CD-R, DVD-R, and DVD+R discs should have a life expectancy of 100 to 200 years or more; CD-RW, DVD-RW, DVD+RW, and DVD-RAM discs should have a life expectancy of 25 years or more.

"Should" is the weasel-word here. The sad reality is, I have CD-Rs from 1994 that work fine today, while other name-brand disks from 1998 or even 2004 went bad! None of this stuff is permanent. Studios are painfully aware that the potential lifespan of data files is much more limited than that of magnetic analog tape and 35mm motion picture film.

I told this story before, but just a few month ago, I ran into a situation with digital picture files of a major 2003 film I had worked on in post, and the files were all NG because we can't get the readers any more. (The perils of saving to an obsolete format -- DTF2, in this case.) Luckily, the HDCam master tapes were fine, and we wound up using these. It would've been better to use the 2K data files, but I don't think it will matter in this case.

For my own projects, I try to operate on Peter Krogh's 3-2-1 Backup Rule: 3 copies of your data, stored on 2 separate kinds of media, with 1 stored off-site (out of your office). I still get screwed every so often by losing a small file here or there, but very infrequently.

Long-term storage for massive archives is a lot more complex. The only thing that works is to store data on LTO tapes and hard drives, and then migrate the data to new formats every 4-5 years. The Association of Recorded Sound Collections has a lot of scientific data and studies on this topic (and by coincidence, they're having a convention in LA this week).

--Marc W.

[studiomprd]

" But at the end of the day they still are usable. "

But at the end of the day they may still be usable.

film has been lost, sound has been lost on all sorts of formats...

and there are as MFW noted, some formats that have become unusable (obsolete)...

but, in fact, are our original recordings really needed in our business, 5+ years after the movie is finished??  (remember, the synced dailies are archived for later use in doing director cuts, special editions, etc.)

[johnpaul215]

I don't think there is a great answer.

Analog sounds amazing, but it is a pain in the ass for everyone. Digital non-linear also allows for simple backups, bilions of tracks (eek) and speeds up the workflow (and reduces labor time).

First off, we are production sound people. When recording digitally, we can use whatever is best for our immediate responsibility. That may be CF cards, or DVD-Ram in caddies or even Lacie Rugged drives. Unlike analog tape, it's kind of up to production to archive digital media (IMHO). They won't come to me in 2043 and ask for the audio from some film we did in 2009.

As for the shelf life.... I have complete faith in nothing. I still help out at a college radio station and I know for sure that many CD-Rs we burned in the late 1990s are unplayable today. We really lost things that way. Did we just buy crappy ones because we had no budget? Maybe. Some were definitely the better quality name brands, and that was mostly done because CD burning was temperamental in the 1990s. Lots of voodoo was involved.

I don't know if the current DVD/DVD-Ram media is significantly better, but those CD-Rs were worthless for archiving.

That same radio station still has a lot of old 2-track reel-to-reels that are fine. They are not strictly climate controlled, but they are in a building with normal office style climate control (as opposed to an old barn).

I have plenty of friends that archived band recordings to DAT in the mid/late 1990s and those DATs are failing too. I know one case in particular where we had to try 3 or 4 DAT decks before we found one that could play the DAT at all. It played fine, but something made the first attempts spit out the tape as junk. Kind of scary.

I suppose there is some sort of better digital backup that archivists are using, maybe some sort of RAID system that rotates out individual drives as they fail.

Hard drives are cheap enough now that I keep at least one backup drives of most of my work. I occasionally copy that to a newer, probably bigger, drive. That requires some effort, but it is keeping files on a new drive regularly.

On the video side of our industry..... I'm not union, so I can only talk about low budget indie films. They are using the same HDDs.

You figure with film, there is no backup of something happens. When I do RED shoots, that card/drive is immediately copied and backed up to multiple drives. *Usually* the people I work with split the drives up and take them home at night. Sometimes that's 3 drives going in 3 cars to 3 locations.... plus a master copy on the camera truck/DIT station.

As the film is edited there is usually at least a copy in two locations. In my experience the editor has their backup system and regularly gives cloned drives to the producer and/or director. You figure if there was only one drive, it would really be worth about half a million dollars.

I did once work on a film that was shot digital. The DIT had some sort of RAID system, but I found out there was no other physical backup on the day the RAID wasn't booting and he was sweating bullets. Two days later  saw his car in the parking lot of a shopping center with his DIT cart in the back (untinted windows) while he was eating burritos. Maybe it's just me, but I thought that was completely crazy. Made me wonder why I was doing multiple backups.

[johnpaul215]

whoa, sorry that was so long.... I was eating my lunch and got on a roll. (no pun intended)

[I-HEAR_YOU]

I have plenty of friends that archived band recordings to DAT in the mid/late 1990s and those DATs are failing too. I know one case in particular where we had to try 3 or 4 DAT decks before we found one that could play the DAT at all. It played fine, but something made the first attempts spit out the tape as junk. Kind of scary.

The reason they (DATS or any other Tape Format) won't play first time is they oxidize. By playing them over a few times the heads of the machine actually polish the tape. Not so good for the machine heads, but that is what works. Make sure you clean the heads after each pass.

All formats of OXIDEE tapes will have this problem after time. The dryer the storage conditions the better. In the good old days we baked tapes to rejuvenate them.

Thanks for the input JP

[studiomprd]

" heads of the machine actually polish the tape "

polish?? is that when the oxide comes off??

and, BTW, magnetic oxides on disc surfaces are also integral to the operation of typical HD's, too

[I-HEAR_YOU]

" heads of the machine actually polish the tape "

polish?? is that when the oxide comes off??

and, BTW, magnetic oxides on disc surfaces are also integral to the operation of typical HD's, too

Yes..... The oxide is actually removed by the heads.

[Marc Wielage]

The reason they (DATS or any other Tape Format) won't play first time is they oxidize.

Not exactly. Oxidize = the chemicals react with air molecules, losing electrons and changing its structure.

What really happens with tape -- analog or digital -- is that it sheds. Once it starts losing its particles, whether metal particle or metal evaporated or iron oxide -- you start running into dropouts and head clogs. I've seen tapes shed so badly, the coating starts to peel off the tape backing in sheets. Then there's sticky-shed syndrome, which is also known as hydrolysis. That's bad, too.

I rarely had a DAT do this, but I've sure seen it with 35mm mag film and 2" & 1/4" reel tapes, and even 2" and 3/4" videotape. Never seen it happen with 1" videotape, but I haven't used 1" video in many years.

--Marc W.

[I-HEAR_YOU]

What he said

Degradation of magnetic tape: binder oxidation studies 

References and further reading may be available for this article. To view references and further reading you must purchase this article.

M. Edge^a, N.S. Allen^{[img alt=Corresponding Author Contact Information]http://www.sciencedirect.com/scidirimg/entities/REcor.gif, a}, W. Chen^{†, a} and C.V. Horie^{‡, a}

  ^aCentre for Archival Polymeric Materials, Chemistry Department, Manchester Metropolitan University, Faculty of Science and Engineering, Chester Street, Manchester M1 5GD, England

  AbstractCommercial videotapes have been artificially aged to quantify extent of binder degradation. Analysis by attenuated total reflectance FTIR shows evidence for the growth of absorptions in the C---O stretching region. It is due to oxidative degradation of the various binders which occurs rapidly, with the magnetic ferric oxide playing a major role in inducing the growth and decomposition of active hydroperoxides. Initial concentrations of hydroperoxides in the binder layers were found to vary significantly with the manufacturing operation. Hydroperoxide decomposition rates increased with increasing humidity levels and temperature giving rise to concurrent increases in the rates of increase of C---O absorption in the i.r. at 1170 cm⁻¹. Although increasing humidity levels may instigate hydrolysis, for oxidation moisture may be serving as a plasticizer. Arrhenius plots are given for the binder layer using a measure of the C---O absorption as the criterion of deterioration. Linear relationships were not obtained suggesting parallel degradation mechanisms.

 

^{[img alt=Corresponding Author Contact Information]http://www.sciencedirect.com/scidirimg/entities/REcor.gif}To whom all correspondence should be addressed.

^† Visiting Research Fellow from CICCA, Beijing, People's Republic of China 

[Marc Wielage]

I think this basically means: too much humidity = bad. Low humidity = good for tapes and media. High temperature = bad for everything.

--Marc W.