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Media Has an Expiration Date

The movies we love live on discs and computers that will all die one day. How do we keep our media alive?

The tragedy occurred as I was rewatching the final season of Six Feet Under, arguably the best television series ever made.

Each episode begins with a death, sometimes comical, sometimes deeply affecting. In this case, the entire episode died. The image started to freeze, displaying rectangular blocks of colour. The audio soon followed. The episode lived up to its name, “The Silence.”

The DVD I had purchased had failed me. Weren’t DVDs supposed to last a hundred years? Come hell or high water, these robust discs were meant to outlast their own obsolescence. Yet, here I was, unable to rewatch the climax of the show on the very DVD set I had bought not fifteen years prior.

It brought to mind the ephemerality of media. Our childhood photos and home videos, the movies we love, the books we devour, they all have expiration dates. The elements will eventually get to them.

How long can we expect these technologies to last and what can we do to prevent our stories and memories from rotting?

The life and death of an optical disc

For a while, it seemed as if streaming services would be the perfect solution for commercial media: every TV show and movie ever released, at everyone’s fingertips, for a simple monthly fee. Your Six Feet Under DVD has succumbed to disc rot? Simply watch the show in high definition on HBO’s streaming service!

But we have seen how precarious this availability really is. Some movies are simply missing: they are not accessible in a legally available format and seem to have dropped off the face of the Earth. As for popular movies, directors like Steven Spielberg and George Lucas have tinkered with their movies decades later, making the original versions more-or-less inaccessible. The streaming copy of The French Connection was recently edited to remove a racial slur. Distribution rights expire and a movie leaves a platform and finds itself in limbo. Surprisingly, some services get rid of their own in-house productions: in December 2022, we learned that HBO was jettisoning Westworld from its streaming platform. Owning a show or movie you love on disc is starting to feel more reliable.

Discs, however, are not perfect, as I discovered. Read-only DVDs made their appearance in 1995, followed by Blu-rays in 2002. Together with CDs and the now-defunct laserdiscs, they are known as optical media. Information is stored onto them using a laser which creates pits on their surface, like strategically placed potholes. When the disc is put inside a reader, a beam of light reads its surface and pits: an infrared laser for CDs, a red laser for DVDs, and a blue-violet laser for Blu-rays (hence the name).

When optical discs entered the market, the only data we had on their life expectancy came from the manufacturers themselves, who conducted accelerated aging experiments in which they subjected their products to extreme temperature and humidity to simulate what would happen over time. As reported by the National Institute of Standards and Technology (NIST) in 2003, the consensus then was that CDs and DVDs sold for people to record on them once (e.g. CD-Rs) would last 100 to 200 years, possibly more. The rewritable ones had a more modest expected lifespan of 25 years or more, but the read-only ones on which movies are sold? There was so little information that people assumed they would last anywhere between 20 and 100 years.

The problem is that there is a lot of variability in the quality of these discs and no easy way for consumers to know what they are getting. NIST’s own accelerated aging testing the following year concluded that CD-Rs that used phthalocyanine as their dye performed better, especially if the disc’s reflective layer was made of a gold-silver alloy. “Unfortunately,” the paper admits, “it is very difficult for customers to identify these more stable media.”

Indeed, the Associated Press ran a story that same year about a man who was unpacking his 2,000-CD collection and who noticed that up to one in five discs had rotted. Optical discs can be poorly manufactured, allowing air to oxidize the surface in a way similar to rusting. There’s also how we handle and store them: they are a lot more fragile than they look. Smudges and scratches can prevent the laser from reading their surface. Even a paper label on top of a disc can start to peel off and create a wobble, which will make the disc unreadable.

Then there’s the damage that can be done by prolonged exposure to light and humidity. I spoke to Linda Tadic, the founder and CEO of Digital Bedrock, a digital preservation company based in Los Angeles. “Back in the day when I had a job at the University of Georgia,” she told me, “I was living in Georgia, in the South, and my personal CD collection was getting mould on it at home just because of the high humidity.” 

If long-term storage is your goal and you can afford it, here is what archivists often do on their end: they keep optical discs in jewel cases made of a plastic called polypropylene, which is inert; they avoid labels and instead write on the inner plastic hub using a water-soluble pen; they store them upright like books; and they keep them on metal shelves between 5 and 20 degrees Celsius (41 and 68 degrees Fahrenheit) and 30 to 50% relative humidity.

All of this care may make us yearn for the films of old, in which case I have one question for you: do you have access to a salt mine?

Spinning its way to an early grave

 Star Wars, What Ever Happened to Baby Jane, and Grease are just three of hundreds of American movies which have been recommended for preservation by the National Film Preservation Board in the United States. Some of them end up in a salt mine.

Celluloid film can last over a hundred years if properly preserved, Tadic told me, and salt mines are naturally dry and cool. Films don’t need to be stored in mines, however; any climate-controlled vault will do. But analog formats like film can’t escape from chemical death. Nitrate film fades and becomes sticky, while acetate film turns brittle and shrinks. Vinyl degrades at high temperatures. Magnetic tapes hydrolyze over time, shedding their precious magnetic particles and damaging the device tasked with playing them back. The life expectancy of a videotape has been estimated as ranging between 5 and 50 years. Analog has drawbacks if preservation is top of mind.

We have made important strides in creating durable media, but those rapid strides themselves are a problem: technology is moving fast, creating obsolescence in its wake. Your DVD collection may outlive the availability of DVD players. If we look back at the VHS tapes of my childhood, the last dedicated VCRs that could read them were made in 2008. There have been over 100 different formats of videotape since 1956. There is simply no way that a player will be found for all of them 50 years from now. As audiovisual archivist Stephanie Renne put it in a webinar you can watch on the Library of Congress website, digital is not forever but analog is dead. Every solution is temporary.

Those discs and tapes you have may no longer be playable decades from now, so digitizing them is a good idea. Home movies can be brought to a company that specializes in digitizing analog media like film and videotape. They might give you a playable DVD in the end, but Tadic reminded me to also ask for a stand-alone computer file. Why? Because one day, DVD players will no longer exist.

As for commercially stamped DVDs and Blu-rays—that DVD set of Six Feet Under I purchased, for example—they are not meant to last a long time. The solution some people have chosen? Ripping those discs using an external Blu-ray drive to create a digital video file that is playable on any computer. There are two problems with this solution. It is technically illegal, as you are breaking the “digital lock” that the company put into place, even if you are doing this for personal use. This is why you are unlikely to get an archivist on the record encouraging this kind of behaviour.

There is, however, another issue with turning a disc into a file that lives on a hard drive. That hard drive will not be functional decades from now. The cloud storage company Backblaze buys a lot of hard drives and they have reported data from over 200,000 of the disk drives they have used over the years. It’s impossible to know in advance when a specific hard drive will die: much like with humans, all we have are average life expectancies. As Backblaze puts it, if they bought a hard drive six years ago, there is a 65% chance it is still alive today. But hard drives eventually kick the bucket.

One of the reasons is that hard disk drives (HDDs), which is an older and more affordable technology in which the disk is literally spinning and generating heat, are rather delicate. Much like the arm of a record player, the arm that reads the spinning disk inside an HDD can break, as it is rather flimsy and is under a lot of stress. Referring to the small USB drives that use this technology, Linda Tadic confessed that her staff calls them “doorstops” because their little arm is going to break at some point.

You may then wonder about solid-state drives (SSDs), a newer type of hard drive that does not spin or generate heat. Their Achilles heel is that they have a limited number of times that they can read and write data. When they are half full, they start to slow down and eventually, without warning, the drive will simply die. 

Our overreliance on computer drives to archive our media, both at home and in the cloud, also comes with a dire warning. We don’t have enough storage media to store all of our media. The plastic and rare earth elements used in the manufacture of hard drives are not infinite, and less than 1% of those rare earth elements (like neodymium) are currently recycled. Data centres command 4% of the world’s electricity (up from 1% in 2010), and a mid-sized centre uses as much water in a day as a thousand American households. As the climate crisis worsens, our dependence on silicone becomes more problematic. 

Is there a better solution we can bring into life?

Life finds a way

Through the use of chemistry, life on Earth has figured out a way to encode data without requiring optical discs or massive data centres. Groups of three bases in DNA are translated inside our cells into specific amino acids, thus providing instructions on how to build proteins. We can now create artificial strands of DNA in the laboratory, and some scientists and archivists are turning to DNA as a potential solution to our storage woes.

The DNA Data Storage Alliance is made up of academic and industry partners, like Microsoft, IBM, and various university centres, with the goal of developing and promoting an ecosystem for data storage based on DNA. To anyone worried that small animals are being sacrificed to obtain the precious molecule of life, worry not: the DNA is synthesized from chemical solutions and does not require any living organism.

The way that it works is simple. Digital data, like a movie file, is made up of 1s and 0s. Much like with a secret code, these digits have to be converted into DNA’s own alphabet of As, Cs, Ts, and Gs, and different ways of doing this have been proposed. Once the DNA sequence has been determined on a computer, it can be fed into a DNA synthesizer which will create the actual DNA molecule from that sequence, much like a house is built from architectural drawings. The resulting molecule is then stored in a tiny capsule, the size of the end of a pencil, at room temperature. While it is true that DNA can degrade when exposed to ultraviolet light and high humidity, for example, it is overall quite robust. DNA from a 1.2-million-year-old mammoth has been recovered and sequenced; I doubt the same will be said of CDs a million years from now.

When the data needs to be accessed, the DNA can be sequenced (or “read”) by the right instrument and its string of As, Cs, Ts and Gs decoded back into the binary language of digital files. Voilà! A whole movie has been reconstituted from a DNA molecule invisible to the naked eye.

Is DNA the future of media storage? Possibly, but even with our future dependence on life’s blueprint, there’s an issue. “The consumers will not have their own DNA capsules,” Tadic tells me. Her company is part of the DNA Data Storage Alliance. “They will still have to go online to be able to access their content in these data centers.” Even when Six Feet Under gets written into DNA, we will have to rely on streaming services to access it.

Book lovers may be reading this with an air of superiority. But even putting aside the eventual obsolescence of an ebook’s file format, there is a problem with reading paper: age. As we get older, many of us will develop some form of visual impairment, like macular degeneration, which makes reading paper books difficult, if not impossible. No matter how you look at it, we are all eventual victims to the transitory nature of information.

There is a military concept we can lean on here: two is one and one is none. Things break down, decay, or simply get lost. When you have two copies, you really have one, and when you only have one, one day you will have none. This is why backups are so important. Archivists typically create a preservation copy—pristine, untouched, kept at a secure and climate-controlled location—as well as access copies. These access copies are the ones being used, and they can get lost or destroyed, but new ones can be generated from the preservation copy. Information technology specialists have the 3-2-1 rule: three copies of your data on two different types of media (CDs, DVDs, hard drives), with one copy being kept off-site, away from your home or workplace in case a fire or flood were to take place.

Data has to be migrated to keep it viable. As Tadic told me, we have to reincarnate it. It’s not unlike taking care of a plant. Failing that, we will have to rely on oral storytelling but fidelity will be sacrificed in the process.

The tagline for the final season of Six Feet Under certainly got it right: “Everything. Everyone. Everywhere. Ends.”

Even information.

Take-home message:
- Optical discs, like CDs, DVDs and Blu-rays, can become unreadable over time, and the best way to store them is to avoid writing on them, keep them in polypropylene cases, store them upright, and prevent extreme temperatures and humidity where they are kept
- Hard drives also die over time: according to data from Backblaze, an external hard drive bought six years ago has a 65% chance of still working today
- Scientists are working on using DNA as a storage medium, by encoding the 1s and 0s of digital files into the alphabet of the DNA molecule and storing the DNA at room temperature
- The key to archiving media and any information is to have backups and to migrate files regularly before the support they are on dies


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