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Re: old never used memorex cd media




Hi,

Gene Heskett wrote:
> perhaps put them in a file drawer and close it to put them in the dark?

At least keep them covered in the spindle by the top paper disk and
the sideward collar.
I have most of my media in dark places. But some sit in their jewel cases
on my desk or on a shelf. No direct sun light, though.

Another problem might be temperature. The dye of optical media is a matter
of chemistry. Whether light has much direct impact seems to differ over
medium types and dyes. But temperature is always an issue.

Librarians seem to fear repeated quick temperature changes of their recorded
media. See
  https://www.clir.org/pubs/reports/pub121/sec5/
for interesting facts and rumors collected by very literate people.
(E.g. you can flood your CD spindle with a deadly dose of gamma rays without
 causing more damage than "discoloration" and a "burnt-substance odor".)


> I've not had a similar occurance with a spindle of dvd-r's, but
> they are a year or 2 newer.

The dye of CD-R[W] sits between the thin upper label sheet and the
polycarbonate disc. This is mechanically less robust than with DVD and BD
where the dye sits between two polycarbonate discs.
If a gap emerges between dye and clear disc, the optical properties will
be affected.


Have a nice day :)

Thomas