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NIST Releases Study Of CD/DVD Longevity

dirkin writes "The National Institute of Standards and Technology has released a preliminary study of the potential lifespan of CD-Rs and DVD-Rs. The PDF study is here. A good starting point for deciding what type of media to purchase to keep those backups and photos kicking around longer. (You DID buy the silver/gold alloy phthalocyanine CDs, didn't you?)"

4 of 425 comments (clear)

  1. This is not surprising. by Krapangor · · Score: 5, Funny
    The data layer of a CD-R consists of cynanide or phthalocyanine organic dyes. However these dyes have a orientated electric charge like water molecules.
    Take now into account earth's rotation and its magnetic field. It induces an albeit very slow movement of the molecules - the data layer degradation. The same effect causes btw certain currents in the Pacific oceans. While the movement is very slow and in the case of the ocean not very important, it does cause damage after a certain amount of time in the case of a CD-R. You should remember that the scale of the information storage units on a CD-R is in the nanometer range. The information is just "washed away" in an entropy-like effect.

    However, you can slow this movement down. The molecular movement in the data layer is directed. So it can be reversed to a certain degree just be placing the CD-R the other way around. So, all you have to do is to mark the position of the CD-R in your rack exactly. And reverse it's position every month or so. This can increase to the lifetime of a CD-R about 150 percent. More can't achieved (in normal environment) because electric machines like your computer etc. create their own electro-magnetic fields. And the effects of these varing fields are much more difficult to negate.

    BTW: the 100 percent wrong place to store your CD-Rs is on the top of your CRT.

    --
    Owner of a Mensa membership card.
  2. remember kids, by Anonymous Coward · · Score: 5, Funny

    Discerning pr0n collectors choose silver/gold alloy phthalocyanine CDs.

  3. phthalocyanine shmithalocyanine by mg2 · · Score: 5, Funny

    I still think that corn CDs are the best idea... you'll just need to reburn every once in a while.

    It only becomes a problem if you're a big nacho fan...

  4. Re:Readers by Anonymous Coward · · Score: 5, Funny

    "I still have tons of 5" floppy disks"

    That could be a problem, since the only drives around are for 5.25" disks.

    -Anonymous Phil