I was having trouble reading files stored towards the outside of several CMC BA3 discs. Windows was having real trouble reading the disc at these locations and throwing up lots of 'bad sector' errors in event viewer.
This is what the disc scan of one disc looked like:
I planned to perform more scans on affected discs and evaluate how many discs had gone bad etc, but I did not have time so I put the disc aside in a nearby jewel case to keep it handy.
I revisited the disc some days later and noticed something strange. The bad files were verifying just fine now. So I re-scanned it and now it looked like this:
Not an amazing scan and worse than a typical 0-day scans of these discs but still...perfectly readable. This was taken about 5 days after removing the disc from the wallet.
Pretty interesting. It seems that:
1 - Storing the disc in a wallet really screwed up the discs..maybe warped them or imprinted a pattern on the surface. Of course many people say not to store discs in wallets but I did not expect such a dramatic and rapid degredation of the disc.
2 - The disc seems to have 'fixed' itself (at least partially) via several days of being stored properly in a jewel case. Maybe something to do with the elasticity of the disc, or the viscosity of the hard-coat?
Anyway I found this pretty interesting. You might think I would never store discs in wallets again but actually I put some more in to see if I can replicate this