If I can first draw a quick parallel between 2
Vauxhall Vectra's parked next to each both look the same but one has
a 3.0 V6 engine the other a lean 1.4 are they really the same?
The same can be said of the discs, disc printing and more so the
copy process also.
As you know you can copy DVD data at between 1x and 16x. We do
not recommend using more than 2X.
Why - a disc spinning at 16X on a DVD is equivalent to 72X on a
CD.
The faster you burn
1> the more errors will be written to disc
2> the more gear changes are required on your drive to keep burning
at a constant speed which in itself causes more errors to occur.
How can you tell if a disc is burned too fast?
Most times you can see with the naked eye by looking at the back
of your disc and see if you can see subtly different coloured bands/
rings on the data area. If so you will most likely find CRC errors
where it changes from one band to another. This can be checked by
downloading CRC Checking software (Sorry CRC = Cyclic Redundancy
Check error - its the check digits on your packets of data)
Next you need to ask are all discs verified?
This takes as long as the burn process itself where every single
disc is validated against the original data to be copied and rejects
highlighted.
So copying is not just copying as you will see.
Same goes for the blank media itself.
Ever wondered why some discs cost more than others?
Its down to a number of factors
a> thickness of material this should be 1.2mm thick exactly.
Thinner media is produced by some manufacturers to avoid paying
Phillips royalties there is also a double saving of polycarbonate
and royalty fee, downside, compatibility of disc with players. Ever
had a disc that refuses to play?
b> amount of Nickel (for DVD) or silver (for CD) put down on
the disc. This is the reflective surface for the laser. 70 Microns
is the minimum recommended - some will skip and put less on this
reduces readability of the disc, some put the minimum, quality discs
put more. Why? to increase readability and longevity of disc life.
c> quality of the dye in the disc. although all DVD-r's are blue
the dye in the disc is affected by UV light (why we always recommend
keeping DVD in a black backed case). Some dyes are more stable than
others. Sony, TDK and Verbatim offer 80 year guarantees others 50
some no guarantee, why could this be, similar analogy to sun cream
could be drawn here, it all looks the same but some says factor 50
some factor 5.
d> In manufacture of the disc, rejects occur. There are only
4 companies globally who make all CD-r and DVD-r and sell them to
the branded companies you know and love. Every DVD-r will have a
small amount of errors built into the plastic through imperfection
in the polycarbonate, dye, nickel etc. different manufacturers have
acceptable levels of errors. Sony TDK, Verbatim having the lowest
acceptable error rates IE Reject more discs from the manufacturing
process. The rejects are then graded where lesser brands accept
the top tier of discs, low quality brands take the next, A grade
media the next then unbranded the bottom tier.
Why do I share this knowledge with you?
Discus Group prides itself on being in the top 5% in the industry
for quality yet bottom 25% for cost.
We implement the best processes, employ the best people, set industry
best practise. We are not afraid of sharing our passion and knowledge
for quality to help the public make informed buying decisions.
I trust you will find this information useful for
future projects you may have and offer you over 300 pages of helpful
information like this on our web site. Use it as a free resource
please.
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