"Reginald P. Smithers III" wrote in message
. ..
Bill Kearney wrote:
He called to say he has recently compiled a 2 DVD set

Are these stamped DVDs or just burned ones? Anyone can download and burn
their own DVDs these days. But burned DVDs are proving notoriously
unreliable. Stamped DVDs (like CDs) are far more reliable. If he's just
selling free data onto burned DVDs it's hardly worth paying anything for
them. Just download and burn 'em yourself.


Why are burned DVD's notoriously unreliable? I know there are problems
with DVD+ and DVD- and people trying to "burn" protected DVD's, but if it
is in the correct format and the orginal is not protected, why are they
having problems? I really have not had any problems with viewing burned
DVD's, is it just because I am lucky?


Burned CD's can change. The reason being the construction. The critical
part of a CD is not the clear side but the shiny side. A pressed CD has the
dimples pressed in and then the coating is applied, and the distance from
the surface to the reflective coating does not change. A burned CD,
diffuses an internal material. If heat and chemistry happen, that diffusion
can grow or change. The reason a CD works is the light source is reflected
from the shiny coating or the diffused internal area. The diffused or
dimple is 1/2 wave length in depth, so you get a cancellation of light. A
dark spot. If there is damage to the reflective surface, then bad data.