2004.01_Dvd Writers-Six Writers on Test Under Linux.pdf

COVER STORY

DVD Writers

Burn Out

When is a DVD not a DVD? There are currently no less than five DVD standards

battling it out to capture their share of the market – and no-one can really say

which way the decision will go. Linux Magazine tested six DVD writers that can

handle all of these standards; read on to avoid making an expensive mistake.

BY MIRKO DÖLLE

normalized, approved by the DVD Forum

[1], and sport the familiar DVD logo as

proof. Rewritable media should prefer-

ably the contactable to this format to

allow them to work in older drives and

players.

The first rewritable DVD medium to be

released was the DVD-RAM. It was origi-

nally intended for data storage, just like

a hard disc. This is why this type of

medium can be rewritten up to 100,000

times. DVD-RAM media are recognizable

by golden markings on the underside, a

kind of sectoring. DVD-RAMs can be

read in nearly any DVD drive.

The other two writable formats

approved by the DVD-Forum are DVD-R

and DVD-RW. These so-called “DVD-

Minus” formats are very similar to CD-R

and CD-RW, especially with regard to

handling. Burning programs write data

to the DVD medium, and rewritable

DVD-RWs can be completely erased, if

required, by the burning software.

why not? Unfortunately, if this is

the only information you have to

base your purchase on, you will soon

find yourself lost in a labyrinth of com-

peting standards. All of them are DVDs,

but the RAM, Minus, Plus, R, or RW

standards all require a specific media

type. As to which disks can be played in

your video DVD player, or on your laptop

– now that is a completely different

question altogether.

Competitive Formats

The “DVD-Plus” formats were created to

compete with the minus formats and are

not official DVD formats – instead of

using a large spiral like DVD-R or CD-R,

the DVD+RW has real tracks organized

in concentric circles, just like a hard disc.

The DVD-Plus Standard is backed by

major players, such as Philips, Ricoh,

Hewlett Packard, Sony, Mitsubishi,

Yamaha, and Verbatim.

The first Plus medium was the

DVD+RW; the write once DVD+R

The Standards Jungle

In the beginning there was just the DVD-

ROM; hard to distinguish from a

CD-ROM at first glance. To allow both

sides of the medium to be used, the data

layer was not created by vacuum deposi-

tion coating, but placed between the top

and bottom surfaces. This makes nearly

all DVDs laminates comprising two disks

with a thickness of 0.6 millimeters that

are glued together (see Figure 1). Apart

from this, the DVD-ROM is very similar

to the CD, except for the fact that the pits

of the data structure are smaller and the

spiral is tighter.

Of course, DVD-ROMs are not writ-

able, but at least they have been

Figure 1: DVDs comprise two 0.6 millimeter disks glued on top of each other. The reflection layer, which

is easily damaged, is thus in the center of the medium and well-protected

January 2004

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Six DVD writers on test

A DVD writer for Christmas? Well,

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DVD Writers

leads to older players mistaking DVD-RW

and DVD+RW for dual-layered DVD-

ROMs, and as the laser cannot focus on

the second layer, the disc cannot be

played.

Figure. 2: Overview of all five writable DVD media: top left DVD-RW, top right DVD+RW, lower left

DVD-R, lower right DVD+R, and bottom DVD-RAM. The differences in reflection characteristics are easily

recognizable

Omnivores and Hunger

Strikers

The battle between the Plus format, as

supported by the manufacturers, and the

Minus format approved by the DVD

Forum, is still raging. This is why we

restricted our test to multiple format

burning devices advertized as supporting

both Plus and Minus formats – this

should leave you on the safe side as a

user. We tested a total of 6 ATAPI drives,

SCSI burning devices are only used in

professional studio nowadays.

We deliberately chose no-name and

low-end DVD media, keeping to a price

range of under US$ 2. Branded products

can be very expensive in comparison;

they often cost three to five times as

much as no-name products – and this is

why media such as Prodisk, Princo, and

Xcitek are so prevalent.

The results were ambivalent: not all

the burning devices could handle all the

media we threw at them. In the case of

the BTC DRW-1004, even brand name

DVD-R media by TDK and Teac refused

to work. Only the LG GSA-4040B and the

Iomega Super DVD Drive accepted all the

media types without complaint.

Sadly, it was not just the case of media

and drives not getting along. The bur-

ning program, dvdrecord , simply could

not handle some media – dvdrecord

refused to burn Prodisk DVD-Rs, no mat-

ter what drive we tried. The table

provides an overview of what drives co-

operated with what media and burning

programs.

medium did not appear until 18 months

later.

RAM. Incidentally, no drivers or special

burning programs are required to write

DVD-RAMs. The burning device acts just

like a hard disc when a DVD-RAM is

inserted and can be partitioned, format-

ted, and written to as required. To format

a new DVD-RAM with Ext3, you can

simply type mke2fs -j /dev/scd0 , before

going on to mount /dev/scd0 /mnt to use

the medium just like a floppy.

Similarities and Differences

In theory, any DVD media can be played,

or read, by any DVD player or drive. As

usual, this theory has very little to do

with real-life applications. The only for-

mat that is more or less reliable is

DVD-R; at least older DVD-ROM drives

and DVD players can use it. One reason

for this is the fact that the DVD-R was

around, or at least on the cards, when

DVD players went into production. The

other reason is that DVD-R most closely

conforms to the optical characteristics of

the DVD-ROM. The reflection level at the

surface is between 45 and 85 percent

(just like the DVD+R) in comparison to

a DVD-ROM. Also, the data are orga-

nized in a spiral, whereas the DVD+R

uses sectors and tracks.

Some DVD players are also capable

of playing DVD-RAMs, however, this

medium was designed for data storage

and uses sectoring in a similar way

to DVD-Plus media. The sectors form

an easily recognizable pattern on the

underside (see Figure 2); this is an

unmistakable characteristic of the DVD-

Problems Reading Plus Media

One of the major issues preventing the

DVD+R from becoming more wide-

spread, is the fact that it was introduced

at a later date. Often, the firmware of a

DVD player will be incapable of handling

DVD+Rs. And rewritable DVD media

are a constant source of trouble. They

reflect a mere 18 through 30 percent of

laser light (see Figure 2) in comparison

to a single-layered DVD-ROM – and thus

achieve reflection levels typical of dual-

layered DVD-ROMs, where the data are

stored in two superimposed layers.

The laser is required to focus differ-

ently for dual-layered media than for

single-layered DVDs. It is quite common

for the firmware to use the level of reflec-

tion as an indicator. This commonly

The Winners

The winner in our test comes from LG.

The GSA-4040B drive costs US$ 150

(retail version) or US$ 140 (bulk), which

makes it 25 percent cheaper than

Iomega’s Super DVD drive. Neither of

these drives gave us even the slightest

cause for complaint throughout our test

series, and both worked perfectly with

the whole range of burning programs

and media.

Also, only the LG and Iomega drives

are capable of writing to DVD-RAMs.

January 2004

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DVD Writers

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These disks (see Figure 2, bottom)

are quite expensive at 8 through 12

US$ each, but you can rewrite them

up to 100,000 times, that is 100 times

more than DVD-RWs or DVD+RWs in

theory.

This makes them an interesting

alternative to streamer tapes or magneto-

optical disks (MODs), in applications

where large quantities of data need to be

transported frequently. Of course, the

DVD-RAM does not offer the same speed

as a Firewire or USB 2.0 hard disk.

3rd spot was taken by the fairly wide-

spread NEC DV-1300A burning device. It

is just as expensive as the winning drive,

but cannot burn DVD-RAMs. The drive

had trouble with Prodisk DVD-Rs using

dvdrecord and growisofs , but handled the

Prodisk, or in fact any, media without

complaint when we used cdrecord-

ProDVD .

The Teac DV-W50DK only came in 4th.

For one thing, the drive is only slightly

cheaper than Iomega’s Super DVD drive,

but cannot handle DVD-RAM media.

Hot on its heels, in second to last posi-

tion, was the Plextor PX-708A, which

weighed in at 280 US$ – the Plextor is

the only drive in our test that can burn

DVD+Rs at 8x speed, and this explains

the price difference. However, the Plex-

tor drive would not burn DVD-RAMs.

There was one thing we noticed in

connection with a faulty DVD+RW

medium. After growisofs had cancelled

the burning process because of the

media error, we had to open and close

the drive tray again manually to con-

vince the burning device to accept the

medium. Attempting to mount the

medium without opening the tray first,

caused our computer to crash in one

case. In other cases, the system and the

mount command both froze for almost

half an hour.

The BTC DRW-1004 drive came out

bottom of the class. Just like our test

winner, the drive costs 150 US$, but it

had a lot of trouble with DVD-R media

by Prodisk, Princo, TDK, and Teac no

matter what burning program we used.

Either the drive refused to write to the

medium, or the medium would not work

in a DVD player later. Xcitek DVD+RW

media also set the drive a seemingly

unsolvable task, in fact, the BTC burning

device is very choosy about what media

it uses. Our advice is to opt for the LG

GSA-4040B instead.

Conclusion

DVD burning devices work on Linux,

although, to be fair, we should qualify

that statement. A bundle consisting of a

burning device, media, and a burning

software may not work, as the dvdrecord

case goes to prove. Our advice is to

choose either the current version of

growisofs , or the commercial cdrecord-

ProDVD (which is free for private use) as

neither of these programs caused us any

trouble.

■

INFO

[1] DVD Forum, the DVD Standardization

Organisation: http://www.dvdforum.org

Overview of Devices on Test

Position:

Picture:

Manufacturer:

Iomega

NEC

Teac

Plextor

BTC

Model:

GSA 4040B

Super DVD

DV-1300A

DV-W50DK

PX-708A

DRW-1004

Internet:

http://www.lgelectronics. http://www.iomega.com http://www.nec.co.uk/

http://www.teac.co.uk

http://www.plextor.be

http://www.btceurope.nl

co.uk/

Cache:

2 MByte

Interface:

ATAPI, UDMA-2

Formats and Burning Speeds

DVD-R / DVD-RW

4x / 2x

DVD+R / DVD+RW

4x / 2.4x

8x / 4x

4x / 2.4x

DVD-RAM / DVD-ROM

3x / 12x

– / 12x

CD-R / CD-RW / CD-ROM

24x / 16x / 32x

16x / 10x / 40x

16x / 10x / 32x

40x / 24x / 40x

Linux Burning Program: Media Supported

cdrecord-ProDVD 2.0.1

DVD-R, DVD-RW,

DVD-R 1

DVD+R, DVD+RW

growisofs 5.13.4.7.4

DVD-R, DVD-RW,

DVD-R 1 ,DVD-RW,

DVD-R, DVD-RW,

–

DVD+R, DVD+RW

dvdrecord 0.1.5

DVD-R 1 ,DVD-RW

–

Includes (Retail kit)

IDE cable, audio cable,

mini-guide, Windows

IDE cable, audio cable,

IDE cable, screws,

audio cable, screws,

DVD-RAM, manual,

software

screws, DVD-R, CD-R,

jumpers,eject tool,

DVD+RW, Windows

Windows software

Manual, Windows

DVD+R, Mini guide,

software

Windows software

Price (retail):

150 US$

210 US$

150 US$

200 US$

280 US$

150 US$

UK available from:

http://www.scan.co.uk

http://www.aria.co.uk

£100

£140

£90

£110

£190

£105

1: Could not write Prodisk DVD-R

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January 2004

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