Re: tlug: CD-R reliability

[Marcus Metzler <mocm@example.com>]

Scott Stone writes:
 > On Mon, 3 Aug 1998, Marcus Metzler wrote:
 > 
 > > Scott Stone writes:
 > >  > 
 > >  > Well, CDs are vulnerable to extreme temperatures and (obviously)
 > >  > scratching... it might have gotten too hot in the plane over to Japan, or
 > >  > too cold (from Germany to Tokyo, the plane would fly great-circle over
 > >  > Siberia, right?).  CDs are vulnerable to cold, as well.  possibly the
 > >  > expansion/contraction of the media under the temperature differential
 > >  > caused very small cracks in the media that are causing the errors?
 > > Yes, I can see that, the question is, why does the number of errors in 
 > > crease. Maybe it`s the hot weather here and the temperature difference 
 > > caused by switching on the airconditioning. But it is strange anyway.
 > >  > 
 > >  > Or you could just have an older or slower CD drive.  Some of those don't
 > >  > like reading certain CDR disks, it depends on the quality of the drive and
 > >  > of the CDR media.  3M and Sony CDRs tend to work better in those drives
 > >  > than the cheaper kinds.
 > >  > 
 > > I have used several differnt drives with more or less success. It`s
 > > true that some seem to better than others.
 > > 
 > 
 > At this point I'm going to say that I suspect low-grade media is the
 > problem here.  Try it with some nice Sony, Kodak, or 3M CDRs and you'll
 > have better luck (probably) :) 
Ok, I have to admit that they were the cheapest my brother could
get. The contents weren`t really that important and you don`t want to
waste too much money on that. I just mentioned the whole stuff to give 
some warning what might happen with CD-Rs. The make of the CD-Rs
varied. There is no correlation between the manufacturer and the
errors. I am not really complaining much because a could watch most of 
the stuff. I was just curious and when I saw that the number of errors 
increased even after they were delivered I was a little surprised. 
Anyway, the quality was still good about the same as a video, which he 
can`t send because I don`t have a PAL vcr here (just in case you are
wondering).

If anybody is curiuos. The mpegs were made by using a Pc-card called
snazzy (http://www.dazzle.com/) which uses some mpeg encoder chips
made by DEC who told us there is no interest in Linux drivers when we
asked them for specs (they even said it is not technically possible to 
write drivers for Linux????). 

Marcus
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Dr. Marcus Metzler
Department of Physics    | $B")(B $B#2#7#4!<#8#5#1#0(B
Toho University          | $B@example.com)A%66;T;0;3#2!<#2!<#1(B
Miyama 2-2-1, Funabashi, | $BElK.Bg3X(B  $BM}3XIt(B  $BJ*M}(B
Chiba 274-8510           | 
Japan			 |
e-mail : mocm@example.com
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