One of the banes of video game, as well as other physical media collectors is the term “disc rot.” The words will send a shiver down the spines in those of us who have large collections of media on disc. Wether its a CD collection, DVDs or disc-based video games, all are vulnerable to eventual failure to what is basically cancer for disc-based media.

First of all, how to discs store and read data?

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Video games, DVDs/Blu-rays and CDs all work off the same technology. A disc imprints on a thin layer of plastic with millions of tiny dots in a spiral that circles the disc. These dots represent the ones and zeros of the code that makes up the data on that disc. A laser passes over these dots as the disc spins, reading the data. The disc player detects if the laser is reflected back; if it is, it reads a ‘1’, and not it reads a ‘0’.

CDs use a ‘slow’ invisible laser with a wavelength of 780 nanometers, DVDs use a faster, 650nm red laser and Blu-ray discs, predictably, use an even faster 450nm blue laser. The frequency of the laser determines how long it takes for the beam to hit the disc and bounce back. The faster the laser, the closer together the data can be placed on the disc and the more data that can be stored.

So what causes disc rot?

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Disc-based media is typically constructed of four layers (sometimes more with additional protective layers); the base which is solid plastic where the data is written, followed by the reflective aluminum data later, then a protective lacquer layer and finally a label on the top. Disc rot occurs when the lacquer layer starts to break down.

When the protective layer fails, the aluminum layer is exposed to air and oxidizes to cause holes or other problems to occur. When this happens, that part of the disc becomes unreadable. This can cause anything from digital artifacts to complete failure of the disc.

This can happen if the lacquer wasn’t prepared properly, or if the discs are stored in volatile environments that expose them to elements that could damage the layer. Some batches of discs are far more susceptible to disc rot than others. For instance, the Gamecube game Metal Gear Solid: Twin Snakes suffers far more disc rot problems than other games of the era.

What can I do to stop it?

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While you can’t stop disc rot once its happened and you have no control over the way your discs were manufactured, there are things you can do to minimize the chances of disc rot from happening.

• Keep your discs in their cases. Not in stacks, not in paper sleeves.
• Keep your disc collection in a cool, dry environment.
• Store discs upright rather than horizontal.
• Avoid touching the surface of the disc to minimize scratches and any contamination of the lacquer layer.

In conclusion

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In the end, we'll likely see lots of video games, CDs and movies fall victim to disc rot as they age. As long as collecting markets remain strong, this will only push the value of well-preserved and fully functional discs higher. The best you can do is to take care of your own collection to make your disc-based media collections last as long as they can.

Thanks for reading. As always, upvotes, resteems and comments are appreciated!

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