Longevity of Recordable CDs, DVDs and Blu-rays — Canadian Conservation Institute (CCI) Notes 19/1

[formdissolve]

Longevity of Recordable CDs, DVDs and Blu-rays — Canadian Conservation Institute (CCI) Notes 19/1 - Canada.ca

www.canada.ca

"The longevity of recordable compact discs (CD-Rs), recordable digital versatile discs (DVD±Rs)Endnote 1 and recordable Blu-rays (BD-Rs) is uncertain, leading to a widespread lack of trust by libraries and archives."

I only have a few CDs from the 80s that have rotted out, but it seems like more DVDs have rot in my collection. Nowhere near as bad as HD-DVDs though, I think I had a 25% rot rate on those in less than 10 years.

 

[Haflermichi]

Unless I missed it, there is not one mention of the difference in physical size of the pits between the compared mediums, other than mentioning the increased capacity for storage of data.
To me this is a crucial issue. The smaller the pits are the more vulnerable they become to physical damage by way of scratches on the substrate. In addition, the read back mechanism must also capable of increased precision and accuracy.
Perhaps that is not the intent of the article. It seems to be mostly about chemical stability.
But this image from wikipedia is telling, and I would think a scientific discussion should include physical damage.

Damage to a CD that could be error corrected might represent irrecoverable data on a Blu-Ray.

 

[LTig]

There was one batch of CDs sometime in the 80s or early 90s which were made with material which did rot quite fast. That lead to a hype about CDs having a much shorter lifetime than advertised. All other pressed CDs however have avery long lifespan, some manufacturers of burnable CDs specified 200 years. I haven't yet found a Cd in my collection of 1000+ which could not be played. Even burned CDs and CDRWs are fine so far.

With writable DVDs though we had very bad experiences when used for data backup. Some could not be read back after 6 months. That was quite unexpected.

 

[somebodyelse]

There was one batch of CDs sometime in the 80s or early 90s which were made with material which did rot quite fast. That lead to a hype about CDs having a much shorter lifetime than advertised.

It was a specific pressing plant rather than a batch - PDO Blackburn. https://en.wikipedia.org/wiki/Compact_disc_bronzing