There is a lot of misinformation being floated in the rec.video.dvd.misc newsgroup. Some posters imply that DVD-RAM drives can write to DVD+RW and/or CD-R disks; others swear that DVD-RAM discs can not be read by any other type of drive. Panasonic, meanwhile, states that all of today's DVD-ROM drives can read DVD-RAM Type 2 discs. All sides are overstating the issues, although the Panasonic group may be able to claim a technical victory, if they are speaking of their own product lineup, as the company has finally begun shipping long-promised DVD-ROM drives capable of reading the Type 2 discs. However, these DVD-RAM discs will play on very few home DVD players.
So, what's this Type 2 about? In addition to the ability to write 5.2GB "type 1" disks that can only be played on DVD-RAM drives, DVD-RAM drives can write DVD type 2 (2.6GB) disks that can be removed from their cartridge and played on some third-generation DVD-ROM players, in much the same way that "MultiRead" was a 3rd generation CD-ROM drive spec.
There is, however, a little more to it than that. To remove a Type 2 disc from its caddy, a tab must be broken off the cartridge that, when the disc is re-inserted for further use, forces the drive to perform subsequent write operations to the disc in "forced verify" mode, which is slower than the standard mode of writing to a disc that has never been removed from its caddy.
It is true that some Multiread DVD-ROM players from Creative, Panasonic (Matsushita), etc., which were originally promised for the Fall of 1998, were delayed several times. Fortunately, a few are now widely available d early compatibility problems have largely vanished. The Panasonic SR-8585/Creative DVD-8400E, for example, is a good 8X/40X drive, and is able to read the Type 2 DVD-RAM discs. It's also a fast drive in audio extraction. As well, DVD-RAM drives can read older Toray/Panasonic PD discs. DVD-RAM drives, including Creative Labs' aggressively priced US$299 first-generation model (which includes a PCI SCSI interface and a blank 5.2GB cartridge), are available now.
See our Panasonic DVD-RAM review for details.
Second-generation models, such as the 9.4GB DVD-RAM Drive announced in May 2000 by Panasonic (Matsushita), are due to be released this summer, with internal models expected to retail for under US$600. Vendors, such as LaCie, offering both internal and external Windows- and Macintosh-compatible DVD-RAM solutions. Indeed, Apple itself offers a DVD-RAM drive as an option on some of its G3 and G4 models. (Note, however, that some Mac users report problems getting this drive to recognize audio CDs.) The first-gen drives typically interfaced to a Mac or PC via SCSI, although the new LaCie model is available with a FireWire interface. These second-generation models are capable of storing up to 9.4GB per disc (4.7GB per side) and are backward-compatible with 5.2GB and 2.6GB discs.
As noted in our DVD Status Report, data transfer rates of 10Mbps (synchronous) or 5Mbps (asynchronous) were claimed for the first-generation units, but sustained transfer rates actually proved much lower: a first-gen DVD-RAM delivered only 1385KB/sec. in our tests. In real-world terms, that speed could be characterized as "unbearably slow." (For comparison, a 2x DVD-R/ROM typically manages 2770KB/sec.; most of today's DVD-ROM drives are rated at speeds of 8x or faster.) Thus, claims that second-generation drives, such as the Panasonic model offered by LaCie, will be capable of transfer rates of up to 22Mbps should be taken with a grain of salt.
Also of note: There are hybrid drives from Toshiba, Ricoh and other manufacturers that read DVD-ROM discs and write CD-R (but not DVD-RAM) discs. These drives typically cost about C$500.
However, there are some complicating issues. Most notably, Software Architects, maker of the Write DVD! and FormatUDF! products for Windows, and DVD RAM TUNEUP for Mac, noted some interesting -- and disturbing -- limitations in its first few DVD-RAM driver revisions. For one thing, the company's documentation for its Write DVD! package noted that file names more than 8 characters long may not copy correctly. Gulp. There were also some issues with compatibility (early units had problems reading Video CDs, and Windows NT drivers are available only as an extra-cost option, although our UDF report discusses a possible workaround). As well, v1.0 pioneers had to struggle with awkward limitations such as the requirement that the drive be formatted with FAT16 for some purposes. FAT16, as hard disk jockies will know, is not ideally suited for multi-gigabyte disks and, in fact, can not even be format a disk at the full capacity of a double-sided DVD platter. Fortunately, version 1.21, available as a free upgrade for Windows 98 users, addresses these issues. It's at www.softarch.com. (Windows 95 Rev A users still have a 2.0 GB limit to the files they can create.)
We've tested a DVD-RAM drive, with mixed results, with Windows 2000. Although both Microsoft and HP confirm that UDF reader software, similar to that which currently requires installation of a third-party driver such as Adaptec's UDF Reader, will be built into Windows 2000. However, we were unsuccessful at writing data to a DVD-RAM disc using the operating system, despite the fact that Microsoft's Hardware Compatibility List suggests the drive should work. As it turns out, an extra-cost (US$80) driver from www.softarch.com is required to format and write to DVD-RAM media under Windows 2000. This software also includes an interesting option not found in the company's earlier drivers for Windows 9x or NT: a FixDVD! utility that can repair (some) damaged discs.
However, users who have invested in this leading edge technology and worked around these early snags report that the drives are very reliable, emulate a CD-ROM reader nicely, and, with writing speeds about 1.3MB/sec, are faster than a floppy drive (although that's not saying much). Best of all, DVD-RAM manufacturers claim a projected life for DVD-RAM media of 30+ years. However, you may find it difficult to track down local suppliers of the blank media. There's only one store in our area that sells them, although it's not hard to find supplies on the Web. For example, you can find the discs available for sale at Creative Labs' online purchase site (www.soundblaster.com).
How much can a single DVD-RAM disc hold? Well, with and first-generation drive and one cartridge alone, you can store as many as 5,200 full-colored digital pictures (640x480, 24 bit/pixel, or 230 minutes of MPEG2 compressed DSS satellite quality video (at 3Mbps), or 150 minutes of MPEG2 compressed theatrical quality video; or more than eight hours of CD quality audio (44.1kHz, 16bit)! Second-generation drives, such as the 4.7GB DVD-RAM drives shown by Hitachi at Comdex Fall '99 and promised for August 2000 delivery double this capacity.
Market Confusion
Broader acceptance of DVD-RAM as a rewritable DVD standard is hampered by competing standards. In one camp, DVD-RAM adherents (most notably, Hitachi, Toshiba and Panasonic) cling to the fact that the drives are backward compatible with Toray PD media and that the next-generation drives will support up to 4.7GB per side. This group, fortunately, has the blessing of the DVD Forum standard group, which in June 2000, announced the "DVD Multi" standard, which ensures that certified drives will be able to read a number of different disc formats:
DVD Multi certified recorders add the ability to write to the following formats:
In the other camp, Sony, Ricoh, Hewlett-Packard, Philips, Mitsubishi, and Yamaha favour the incompatible DVD+RW standard. At least Hewlett-Packard came to its senses in Nov. 99 and canceled the bright idea it announced back in June, 1999 of pre-announcing a DVD+RW drive that would, upon its release in Dec., write discs completely incompatible with every drive currently on the market. HP and other DVD+RW supporters now say their second-generation models will not have this problem and will support up to 4.7GB of data per disc. Philips, at PC Expo in June 2000, said it intends deliver a drive that writes discs compatible with standard DVD-ROM drives by year's end; Ricoh promises one by mid-2001.
A Philips technology paper reveals some intriguing capabilities of the +RW format. It includes extra sector location features that allow it to play segments out of order without a break in the video. This is the sort of feature that is ideal for non-linear editing applications. This capability, says Philips, is not present in the standard DVD format.
In short, these compatibility concerns and conflicting standards are holding back acceptance of rewritable DVD technologies.
What's Ahead?
Perhaps the next big thing in DVD will be the emergence of a new class of 'consumer video recorders' that use DVD-RAM or a competing format. The first of these -- a model called the DVM100 from Hitachi that stores 2.9GB of data on special 8cm DVD-RAM discs -- was released in June 2000, carrying an estimated price of US$2283. At the product's launch, Hitachi recorded video to the diminutive disc with the DVM100, then removed it from the camera and immediately played back the video on a PC with an MPEG-2 decoder and a DVD-ROM drive. The disc was then played on a set-top home DVD player.
Digital Photography Review has additional details.
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