[Techtalk] viewing CD-RW disks in DOS

[Alvin Goats]

>> Conor Daly:
>> If you're able to see ordinary CDs in DOS, you should be able to see CDRWs also. 

I found that the older drives I have (up to 56x speed, but before
"silver" CD-R's) cannot reliably read the "silver" CD-R's, cannot read
the CD-RW's at all; my portable CD players can play the "silver" but
won't play CD-RW, but they ALL can read CD-ROM and the "blue" and
"green" CD-R's. 

I don't remember the details, but it has to do with the angle of
deflection by the laser after the burn and with the different materials
used in the dye and the the type and configuration of the laser/detector
reader of the player. FYI, I *CAN* play CD-RW music CD's on my CD-RW
drive, but not on anything else I have. The Yamaha FAQ below has the
explanation.

One other thing that I've noticed during burning, on some CD-RW disks
that give me trouble (Memorex on a Yamaha CRW-4260) there is a
"refocusing" statement. It is as if there is a difference in the
refraction of light that requires the laser to be refocused, which
appears to be just outside the drive's focus ability. If so, this may be
part of the blue/silver/black/CD-RW disk issues. 
Deep Blue: azo dye.
Blue or Green: cyanine dye.
Silver: phtalocyanine dye (colorless).
Gold:	phtalocyanine dye (colorless).
CD-RW: an alloy of silver, indium, antimony and tellurium.


A source for more information and FAQ's on CD-R and CD-RW disks:

http://www.mscience.com/faq.html#CDR

http://www.emtec-webassistance.com/en/Cd/Information/Cd_R/

http://www.yamaha.ca/computer/support/faq/g101.html

http://www.techadvice.com/tech/C/cdr_media.htm

http://www.mediastore.com/cdr/cdr_faqs.asp