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On Mon, 25 Aug 2003 15:39:11 GMT, "Just a nutter"
<> wrote:
>> Someone reported on the AVS Forum that Vivastar DVD-Rs recorded about 6
>months
>> ago would no longer play. Is DVD rot caused by the cheapness of the
>blanks or
>> the way they are stored?
>
> It is my understanding that the disks we use can not be the subject of
>DVD Rot.....I am told that Rot can only occur in commercial disks that have
>multi layers. The Rot occurs at the boundary between the layers.

Whether or not people want to call it "rot", all it takes for a DVD-R
to go bad is for the organic dye inside to change its reflectivity
enough to transition to different data. When you consider all it takes
is a certain powered laser to cause the dye to transition, why can't
poorly made organic dye start to break down on its own over time
without a powered laser? Anyone who might think chemicals (organic or
not) are guaranteed to be perfectly stable over time is wrong.

The answer is the dye break down can occur, and I've had it happen on
Princo media in under a month. Nothing else can explain perfectly good
media becoming unreadable after sitting on a shelf away from light or
excess heat. I still call it rot, but some people insist that it
isn't. Other better brands of media have not yet died, but that's not
to say they won't someday.

I agree it's a bit risky to archive important data on DVD+-R until
it's been around for more years. I'm probably wasting my time
archiving what I have because it'll probably go bad in a few years.
With CDRs at 10-20 cents each, it's not so bad if they go bad (and
none of mine have so far) but with DVD+-Rs in the $1 to $1.50 range it
is bad if they start to rot en masse.

In article <>, Jacky
<> wrote:

> Whether or not people want to call it "rot", all it takes for a DVD-R
> to go bad is for the organic dye inside to change its reflectivity
> enough to transition to different data. When you consider all it takes
> is a certain powered laser to cause the dye to transition, why can't
> poorly made organic dye start to break down on its own over time
> without a powered laser? Anyone who might think chemicals (organic or
> not) are guaranteed to be perfectly stable over time is wrong.

And anyone who thinks DVD-R manufactures just use any old dye is
equally wrong. Longevity was likely a factor in the very design of
DVD-R technology, and the dyes used in the process would obviously be
formulated to remain stable. Besides, a catalyst such as oxygen would
be required anyway.

> The answer is the dye break down can occur, and I've had it happen on
> Princo media in under a month.

You get what you pay for.

> Nothing else can explain perfectly good
> media becoming unreadable after sitting on a shelf away from light or
> excess heat. I still call it rot, but some people insist that it
> isn't. Other better brands of media have not yet died, but that's not
> to say they won't someday.

Sure, maybe 40 years from now.

> I agree it's a bit risky to archive important data on DVD+-R until
> it's been around for more years. I'm probably wasting my time
> archiving what I have because it'll probably go bad in a few years.
> With CDRs at 10-20 cents each, it's not so bad if they go bad (and
> none of mine have so far) but with DVD+-Rs in the $1 to $1.50 range it
> is bad if they start to rot en masse.

Doesn't matter what the media costs, it's the content.