As you know, a CD or DVD must be handled with care, or it will acquire scratches that eventually make its data unreadable. Now, I pay good money for those discs, and want to keep them for as long as possible, like books in a library. ONE solution is to take each CD or DVD, just as soon as you open the package, over to some ripping software, so you can make legal archival copies. Then you put each original disc in a safe place, and use the copies until they become scratched to worthlessness. THEN you dig out your saved original disk and make more copies.... (Of course, if the discs were more scratch-resistant in the first place --an idea already posted here-- and lasted as long as books, then there would be little need to make copies, would there?)

You may be aware that the motion-picture and music-recording industries are totally against any such legal usage of the discs they sell. They WANT your original discs to expire as fast as possible, so that you can keep buying new ones. I suppose, if they ran a bookstore, they'd demand that you trash each book you buy, just as soon as you finished reading it -- and they'd make libraries illegal, too. In their own industry, though, since they can't actually make you wear out your discs fast, they are about to implement the next-best-thing that they can think of -- discs that automatically become useless a couple of days after you break the seal. Their surfaces turn black, preventing access to the data layer inside the discs! While I don't know the exact technology involved, I suspect the trick relies on the oxygen in the atmosphere, which causes fresh-cut apples to quickly turn brown.

The blatant greed that is behind this conspiracy to cost you more money (AND to fill the landfills even faster) is intolerable, and must be fought. I therefore suggest that a special oxygen-proof coating be developed, which can be applied to each CD or DVD disc as zippily as possible after the seal is broken. It has to be easy to apply, always yield a smooth transparent and uniformly thin coating, and dry zippily, too. If it is also a scratch-resistant coating, then that could be its prime advertising focus, and none of the conspirators will ever be able to stop the marketing of this product.
-- Vernon, Jul 24 2003

The self-destructing DVD http://slashdot.org...=198&tid=137&tid=97
Here's the news blurb (with links) that led to this idea. [Vernon, Oct 04 2004, last modified Oct 21 2004]

Part Two http://www.wired.co...,1294,62083,00.html
The rejected self-destructing DVD [Vernon, Oct 04 2004]

Hooray! Being Baked!!! http://www.newscien...s.jsp?id=ns99996583
Now if only this was available for home use! [Vernon, Nov 02 2004]

Could I spray this on my apples to stop them from turning brown then?
-- DeathNinja, Jul 24 2003


Epoxy or clear nail polish would probably do the trick, but why not just make a copy? It would be second generation, but probably of no worse quality than reading the original through a layer of whatever.
-- phoenix, Jul 24 2003


phoenix, beware of dissolving the original disc, if something like nail polish is used! Yes, I know one could still make a copy of a freshly opened self-destructing disk, but eventually this means you will only possess the copy and not a ledgible original, and the Industry Conspirators would then happily arrest or sue you for piracy.
-- Vernon, Jul 24 2003


I've actually been involved in the development of a protective cover for CDs... the biggest problem is that whenever you add a coating or film, etc... is that it not only protects the disc from being damaged, but it also protects the disc from being read.

Many have tried this, and spent much money on it... My company has built several prototypes for a customer pursuing exactly this... after many dollars and much failure, I think this will be dropped. I even researched static cling films and whatnot that might allow the disc to remain readable, no luck so far.

Great idea though, no bones here...
-- X2Entendre, Jul 24 2003


// and they'd make libraries illegal, too. //

Obviously not, given that many libraries (in the UK and the US, in my experience) do lend videos and DVDs.

Ditto video rental shops.
-- JKew, Jul 25 2003


X2Entendre, I'm not surprised that others have worked on scratch-resistant coatings for CDs/DVDs; certainly I'm not the first person to be annoyed by scratched discs -- although I learned earlier than most, since I have a collection of 12" LaserDiscs, a technology that was on the market well before CDs came along. (The movies on those discs are nearly the same quality as DVDs, so as long as spare funds are tight, they represent about 100 movies I don't have to buy on DVD.)

Anyway, the reason for this particular annotation is to note that even while I was writing the main idea text, I was a little concerned about how workable it might be. The problem was (my first thought), when you add any thickness at all to the surface of a disc, you effectively move the data layer inside the disc away from the focal point of the laser data-read system. I don't know how much focus-adjustment there is in the average CD or DVD player, but thought that there would be a little. On the other hand, that problem is actually a non-problem, because inside the drive, the disc is lifted from the tray (duh!), and so the relative locations of laser focal-lens and data layer will remain the same. This leaves issues of index-of-refraction and transmitivity of the coating (CDs use infrared laser light, and DVDs use red laser light) -- so if the coating is much different from the composition of the main body of the disc, then such problems as you describe are quite likely. I do find it difficult to believe that these issues cannot be solved, though.

JKew, libraries exist partly for historical reasons (remember how expensive it was for scribes to copy books?), because there was no other way to expose many people to the few books that were published each year. Even the advent of the printing press did not really make a dent in the need for and usefulness of libraries -- up until perhaps 20 years ago. Modern computerized typesetting means that books technically don't have to cost much more than the paper and ink they consist of -- and most paper gets recycled these days (a significant cost-reduction factor). But the book-publishing industry is almost as much of a cartel as the RIAA or the MPAA, and so prices of books are not reflecting their modern lessened cost of production. Likely the publishers will claim that simply because books CAN last a long time and ARE frequently shared, that is why they "must" maintain high prices...not to mention that the Web is probably cutting into the need for libraries, or even on-paper books altogether. The Web IS a worldwide and always-open library...and the more this aspect of reality cuts into book sales, the longer that books will keep high price tags (which in turn will drive people away from buying books!).

Regarding the rental industry, this is not a real problem, because of an unfortunate tendency of people to carelessly handle (or even mistreat) things they don't own. The result is damaged discs (and tapes!) which must be replaced, much to the profit of the manufacturers. As for libraries that stock CDs and DVDs (and tapes), I do realize they don't carry many copies, so the rate of exposure of those discs to the population is just a trickle, compared to the rental industry (or piracy). This would be the ONLY reason why the Industry Conspirators would let libraries continue to exist (besides tradition) -- provided, of course, they first made sure it was impossible for anyone to copy a borrowed disc. See, what they really want is for nobody to own any copies at all; they want you to pay for each and every time you play any song or movie...and just as soon as they think they could get away with it, they'll sue anyone who MEMORIZES a song for copyright violation!
-- Vernon, Jul 25 2003


Folks, I just saw an article indicating that those time-limited DVDs have hit the market, but hardly any are being sold. Hooray!
-- Vernon, Feb 06 2004


[Vernon] - I was under the impression that it was legal to make a single copy of a music CD for "personal use," but not of software CDs - although I honestly can't attribute this to any source, and don't even know if it's US or Australian law.

I can't imagine the rationale behind such a distinction, but it seems to be in my brain. Someone around here must be a walking encylopaedia of copyright law...
-- Detly, Feb 06 2004


[Detly], you are allowed to make an archival copy of any copyrighted thing that you buy. The idea is that you have the right not to lose what you paid for. Naturally, you are not supposed to use the archival copy unless the original is damaged beyond usefulness. What **I** would do is make a new copy to use, and keep the archive in storage. But I don't know for sure how that plays with the lawyers. For safety against lawsuits, you probably should put the damaged original in storage along with the archive. ALTERNATELY, as soon as you get the original and copy it, put the ORIGINAL in storage, and just use your "archival" copy, which you throw away and replace whenever it gets damaged too much. I think any judge with sense would see the equivalency between the two notions, although the first means you have two copies of the original on-hand.
-- Vernon, Feb 06 2004



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