right, I just posted this in response to those worried about storing DVD discs stacked in spindles. Its nothing to worry about whatsoever IMHO. Any extremely fine scraches you may get from a few fine dust particles isnt signifigant... jco
-----Original Message----- From: Rob Studdert [mailto:[EMAIL PROTECTED] Sent: Tuesday, January 03, 2006 6:14 PM To: [email protected] Subject: RE: And what about storing the CDs/DVDs? On 3 Jan 2006 at 16:05, J. C. O'Connell wrote: > DVDs in my experience are not realy that physicallly sensitive to dust > ( can be wiped off) or even lots of light scratches. I have checked > out from a public library many hundreds of DVD-Videos with literally > dozens sometimes hundreds of scratches on them that played fine on > Video and PC drives. Its amazing because you would not believe > how bad some of them look, really scratched up bad from > a public library, w/ years of daily usage. Seems that > a scratch has to be real severe/deep before the data is > irrecoverable on those at least.... If you've ever seen CD alignment test discs one in the set will often have a series of opaque dots in increasing sizes silk screened on the play surface of the disc. These are designed to test the players hardware and firmware resilience to obscured data. Any good CD player should be able to play a disc with a 1mm opaque dot without loss of data (DVD is slightly less robust). The optical system uses the refractive properties of the media such that the laser beam has a spread of about 1mm at the surface of the disc, only at the discs internal playing surface is it focused. Data integrity is further enhanced by the particular way that the data is written to the disc, there is a lot of redundant information and the data of each frame is interleaved along the track. Rob Studdert HURSTVILLE AUSTRALIA Tel +61-2-9554-4110 UTC(GMT) +10 Hours [EMAIL PROTECTED] http://members.ozemail.com.au/~distudio/publications/ Pentax user since 1986, PDMLer since 1998
