Dear Microscopists,
I just had the idea to look at a computer CD under the microscope.
This is what it looks like.
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Hoping that it will interest you.
Regards
Didier Barbet
Near the center of the CD
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Re: Near the center of the CD
Interesting. So where are the bits?
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Re: Near the center of the CD
Hello Lou,
This is only a border near the center of the disk.
The pieces of information are stored on the silver part.
On the silver part, there is a protective layer, below a reflecting layer, and below a recording layer where the bits are.
Regards
Didier
This is only a border near the center of the disk.
The pieces of information are stored on the silver part.
On the silver part, there is a protective layer, below a reflecting layer, and below a recording layer where the bits are.
Regards
Didier
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Re: Near the center of the CD
There is a difference between a data CD-R and a Music CD-R. A Music CD-R has, as I recall, three dots in that inner band that identify it as a Music CD-R to devices dedicated to making a music CD. These tell the recorder that this is a Music CD-R. Music CD-R discs cost more than a data CD-R because the price difference goes into a pool shared by music labels to address royalty issues arising from piracy from home-grown copies sharing commercially produced music CDs.
Mike
Mike
Michael Reese Much FRMS EMS Bethlehem, Pennsylvania, USA
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Re: Near the center of the CD
My audio cd-player accepts both music and data cds. Only half of the data cds are rejected. Which I always thought strange, since audio data allow for some errors whereas a data backup must be byte perfect. If the test is in those dots, it seems not too reliable if also some data cds are accepted.
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Re: Near the center of the CD
But the question is, does your audio player also record? I have downloaded audio in a computer and written it to CDs that will play anywhere - home car whatever. Some player/recorders such as my SONY are very uppity about what CDs they will record on. In other words, it must be a Music CD. This makes perfect sense since SONY is also in the music (and movie) business. However, I have found that if a CD is written to the RED BOOK specifications in a computer, they will usually play in anything.
Mike
Mike
Michael Reese Much FRMS EMS Bethlehem, Pennsylvania, USA
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Re: Near the center of the CD
Nope, not even if I'd put a blank music score paper in It's that kind of old fashioned single function device. But I get your point now.
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