Copying CD to CD to CD ...

[Cooter]

I read in a reputable book that because of the peculiar block / file
structure CDs use that if I make 2nd, 3rd or so on copies (copy of a copy of
a copy ...) there is danger of data loss after about the third or fourth
generation. Their explanation made sense. If I always copy from the CD to
the hard drive, then back to a CD will this prevent such 'generational' data
corruption?

Thanks,
Cooter

[Graham]

"Cooter" > wrote in message
om...
> I read in a reputable book that because of the peculiar block / file
> structure CDs use that if I make 2nd, 3rd or so on copies (copy of a copy
of
> a copy ...) there is danger of data loss after about the third or fourth
> generation. Their explanation made sense. If I always copy from the CD to
> the hard drive, then back to a CD will this prevent such 'generational'
data
> corruption?
>
> Thanks,
> Cooter
Now if what you think is true,. think real hard, how would having a file
copied twice be less damaging than copying it once? This what you will be
doing if you copy it to your harddrive then burn it. Not that it is truly a
huge issue to begin with. It is always a preferred method to make an image
then burn from the image. If you have a large hard drive you can even retain
the image for a period of time in case you decide to make more copies.

[LVTravel]

Think what is being said here. CDs are written in digital format (1s & 0s).
When a computer reads the signal from the CD Drive it is "stored in memory"
until it is written in digital format again to a new disk. No loss of
signal will occur or the CD would not be able to be read and verified by the
creating CD drive. (Would fail CRC at verification).

If the signal was analog instead of digital, signal degradation could occur
with repeated copies or with distance, i.e., vhs tapes, audio cassettes, old
telephone systems, and even Xerox copies of paper. Each generation will
degrade from the previous unless there is an amplifier in the middle. The
amplifier will copy any noise introduced into the line.

I have successfully made 6th generation copies of program cds, data cds and
music cds with no loss of quality.


"Cooter" > wrote in message
om...
> I read in a reputable book that because of the peculiar block / file
> structure CDs use that if I make 2nd, 3rd or so on copies (copy of a copy
of
> a copy ...) there is danger of data loss after about the third or fourth
> generation. Their explanation made sense. If I always copy from the CD to
> the hard drive, then back to a CD will this prevent such 'generational'
data
> corruption?
>
> Thanks,
> Cooter
>
>

[Graham]

"LVTravel" > wrote in message
...
> Think what is being said here. CDs are written in digital format (1s &
0s).
> When a computer reads the signal from the CD Drive it is "stored in
memory"
> until it is written in digital format again to a new disk. No loss of
> signal will occur or the CD would not be able to be read and verified by
the
> creating CD drive. (Would fail CRC at verification).
>
> If the signal was analog instead of digital, signal degradation could
occur
> with repeated copies or with distance, i.e., vhs tapes, audio cassettes,
old
> telephone systems, and even Xerox copies of paper. Each generation will
> degrade from the previous unless there is an amplifier in the middle. The
> amplifier will copy any noise introduced into the line.
>
> I have successfully made 6th generation copies of program cds, data cds
and
> music cds with no loss of quality.
>
>
The degredation is not from the 1s and 0s, it comes from the errors in
reading and scracthes smudges etc. If each time you copy you lose a little
bit, it eventually becomes fatal.