Re: CD Life Expectancy
I had a chance to talk to "my" CD Archival Characteristics fellow today. He is trying to help industry develop techniques so that they can rate unrecorded CD's for expected archival life. If successful, you'd find "30 year, 50 year, etc" CD-R s on the market. We are a long way from having these ratings at the present time. Even the same brands are inconsistent in their life.
One very useful factoid is that Roxio Easy Media Creator 8 now has a feature that allows one to find how hard the error correction is working when playing a CD. The parameter one cares about for CD-R's is BLER max (maximum block error rate), which has to be under about 220. For DVD's the parameter is PImax or PIEmax which must be under about 280. My expert suggested that one should keep a log of these readings vs time for each of your archive disks. This should help determine when it is important to copy the data onto a fresh disk. My expert pointed out that the same disk will give different BLER readings when played on different drives, etc.
I hope this us useful.
seacue