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Bill Gill

On 1/12/2015 2:01 AM, wrote:
Someone recently told me that if a DVD is put on PAUSE and left that way
for a long time, the laser will damage that part of the DVD.
I dont think that is true, but I'm not sure.

I know if a VCR is left on pause the spinning head will wear the tape
at that spot. (which is why a VCR will shut itself off is left on pause
for too long). But I dont think the laser keeps reading the DVD when
it's paused. I'm thinking the laser is turned off, and whatever picture
is paused on the screen is just stored in memory. From my recollection
of what I have heard, any optical disc (CD, DVD or Data disc) is read by
the laser and "READ AHEAD", whereas the digital code is put into memory
ahead of what you are actually seeing or hearing. This I was told is
why a movie wont start playing immediately when it's inserted. I know
the computer discs (which are usually slower to load), always spin up
and read the disc before a menu pops up on the screen. This delay is
real noticable when installing Windows or any operating system.

Anyone know the truth about this?

Even with the disk still spinning there wouldn't be any
wear, since the laser wouldn't be concentrated on one spot.
As far as I know the disk would keep spinning. It doesn't
take that long for the disk to spin back to where it was
reading because it is spinning very fast so there would
be no perceptible loss of time waiting for it to start
reading again. The data is buffered, but I think that is
more a matter of having time to get all the data together
before presenting it. Technically it is possible for
the data on the disk to be stored discontinuously. That
is one part could be on one part of the disk and the next
part on a completely different part. I doubt if it is in
a DVD, but if you make a disk image of your computer hard
drive it could quite easily be that way.

Bill