HAL-PC Magazine

A DVD (or CD for that matter) recordable (bit of blank media) contains a layer of chemical substrate (the purple dye sandwiched between the plastic layers); that layer that is hit (burned) by a laser. The DVD laser creates small holes or non-holes (skips) in this chemical substrate. Hits or non-hits are called pits and lands, also known as 1’s and 0’s; off’s and on’s, etc. Enough of them together in the right scheme and you have MUSIC, VIDEOS, PHOTOGRAPHS, or FILES full of stuff. A dual layer contains two layers of this chemical and by adapting the laser intensity, both layers can be written. Tricky, a very complicated process, and requires a lot of precision and the right materials to make sure that after the data has been burned, it can still be read back like a commercial DVD without errors.

Reading back has been the biggest challenge in development of the private label D9 format (D9 format is used for commercial DVDs, 8.5 to 9 gigabytes). Most current DVD home players were not designed to read back private label, dual layer DVD recorded discs. They do read back physically pressed commercial (DVD D9) dual layer discs. Development has been focused on making the private label DVD recorded disc compatible with the commercial DVD dual layer discs.

Philips announced the feasibility of a D9 format in early 2001, and Pioneer quickly jumped into the game. Most recently the D9 recorders and media have hit the market place. Hollywood folks are not at all pleased with this development, as one could imagine. Your commercial DVDs can now be backed up with virtually no loss of signal, no compression necessary, and at 4X on Verbatim’s newest media.

If you have an older DVD burner, a 1X, 2X, or 4X unit, you will have to replace it to burn a dual layer disc (the laser unit is not powerful enough). Most 8X and up burners have better lasers and those units may be upgradeable by flashing the unit’s firmware.

Pioneer just recently put a new unit on the market -- the DVR-A08XL, which is a 16x DVD Dual Layer; it does 4X with DL+R media. Apparently, the DASH (DL-R) media is not yet ready; Pioneer is the leader of the DASH group. But the competition continues in the media arena. NEC, ASUS, SONY, and Opturite also have 16x DUAL Layer DVD-DL models… as low as $70. All of these units also do CD-R, CD-RW, DVD+/-R/RW.

One little hook, the DL+R D9 media costs $9+. That is the 2.4X DVD DL+R D9 media, not the 4X DVD DL+R D9 by Verbatim, which is nowhere to be found but it is talked about. For my money, it makes more sense to just buy an extra copy of the DVD and save a lot of extra work. You make a coaster out of a DL+R D9 DVD and Ouch!, you are going to notice it. There are also the usual media problems, in that not all brands of media work in all burners, not all DVD player units will read all brands of media and if your playback DVD is old, then figure on a new unit. This will all be resolved, just as with the 4X +/- DVD single layer (D5) media, which has dropped dramatically over the past several months.

The base price of the newer Dual Layer DVD units are cheap enough. The quality of the burners are improving…dramatically. PRICE of the media will come down; quality and compatibility will improve for sure. For now, an 8x dual burner is still a winner; $35 for a hundred of 8X white hub printable blanks, FOB my door, sure looks better than $9+ each.

Robert Du Vernay is a HAL-PC member who instructs both the CD and DVD Burning for Everyone classes and conducts a New Internet Users SIG on the 1 st Saturday from 1:30 - 3:00. He can be contacted atrpd@hal-pc.org