August 24, 2004

Yet another standard... DVD-/+9

Although BluRay is due out fairly soon, the 'standard' DVD format just got another shot in the arm. This is available in both + and - formats. There is a writeup on this at DVD Industry Insider Report - August 20, 2004: bq. Both have two thin substrates joined by specially designed UV bonding materials. When the laser is through writing to the first layer, it increases power slightly and begins writing to the second layer. When you are playing the dual-layer DVDR9 disc (+ or -) you’ll have to look hard to notice the switch over from one layer to the other. bq. The result is a full 8.5GB or 4 hours of DVD-quality (16 hours of VHS –quality) video. Some manufacturers may refer to the capacity of 4 hours of SP and 16 hours of EP so make certain you understand the playback quality you want before you begin writing your write-once discs. bq. The other big similarity is that the DVD specification requires that players and drives read dual-layer discs. If you encounter one that will read "standard" +/- discs but won’t read DVD+/-R9 media it means the manufacturer had a design flaw which they should correct at no charge. The 8.5 GB will be nice but if it cannot be played back in all players, what is the point... BluRay is a true technological advance using the shorter wavelength of near-UV light to pack more bits into the same space the relatively long wavelength InfraRed used today. How much more? Try 25 GB for a single-layer disk and 50GB for dual-layer. Kinda makes the 8.5GB look a bit... puny by comparison? Hmmm??? Posted by DaveH at August 24, 2004 11:20 PM