Disks degrading over time...

[Kingnog]

I've heard a lot about both CD and DVD media degrading over time. Especially Princo's, which seem to be hated by everybody....
When a disk 'goes bad' after, say, a month...what does that mean? Can it play the movie, but has some errors and skips? Is the drive unable to read the disk at all?
I was wondering if it was possible to make a copy of the 'bad' disk and get it working again on fresh dye

[instigator_008]

This is known as "Rot". Basically, the dye breaks down making it impossible for the dvd to be read. Therefore, you will not be able to rescue reliable data from any disc suffering from rot.

[Kingnog]

Well, thats not good, considering I just bought a 100-pack of princos...

[spiderman2k1]

I buy alot of CompUSA media and it's Princo's and I had them for about a year so far with no problem's. It come's down to how good your burner is. I had a Ricoh 2600A 2X CDR burner some stuff I can not read to this day and it was picky on the media I put in it. I then got a HP burner took any brnad of CDR's ever disc I have burned with it still work's fine. IF your burner is good at burning cheep media you will not have problem's

[Kingnog]

I have an LG GSA-4040B ...

[valzuniga]

I bought a cdrw drive back in the 90's, a hp 7100i when the top speed was 2x, many of the cd's that I burned at that time, are now failing or not working at all, I would say to back up your cd's about every 5 years, or atleast use good media, and back up not as often.

[Gazorgan]

Most of my 'rot' can be traced to Sharpie markies on plain (non silkscreened) disks. The can eventually eat down to the dye layer and contaminate it.

[smearbrick1]

The ink from a sharpie is not acidic or basic enough to eat (or rot as you put it) through the polycarbonate layer protecting the surface of the disc. Regardless whether the disc is plain or matte finish. There is still a polycarbonate layer protecting the dye. In fact, the dye is sandwiched between two polycarbonate layers. Must be something else.

[epo]

CD-s aren't sandwiched...

Roting DVD-s *can* be rescued at least up to some point. That's because DVD drives (+PC) are much better at error correction than players and DVD includes really heavy error correction. (I'm currently working on my first Princos, my player refuses to reconise)
Another story with CDDA, VCD, SVCD as there is no error correction code. So, remaking Audio-CDs after every 5 years results to eventual quality degradation. Tests prove that degradation is audible in 6th-7th generation, but these tests didn't include aging.

[valzuniga]

Where are these "tests" you speak of? I would very much like to read them!! Please post a link to validate your information, and for further interest of the readers.

Thank you in advance, this is very interesting!!

[NightWing]

Sorry. Top layer usualy lacquer.

Here is the breakdown on the layers of a cdr.
http://www.osta.org/technology/cdqa15.htm

PS: When did Alaska become a country? Go to www.3m.com and check the list of countries. Click on Select a country.

[tompika]

PS: When did Alaska become a country? Go to www.3m.com and check the list of countries. Click on Select a country.

I was looking for "Select a country" but all I found was AREA and LOCATION...

[NightWing]

Not per say pick a country but the line "area of the world" and the bulk being countries was slightly funny.

Usualy they include the two states and or areas under US protection as the US. Here it kind of funny to see Alaska on the list.