DVD recordable

Embedded Data: A DVD-R disk (also applies to DVD+R) which still has space available. Data is burned onto the disk with a writing laser.

DVD recordable and DVD rewritable refer to part of optical disc recording technologies. DVD optical disc formats that can be recorded by a DVD recorder, (written, "burned"), either write once or rewritable (write multiple times) format written by laser, as compared to DVD-ROM, which is mass-produced by pressing, primarily for the distribution of home video. DVD recordable is a general term that refers to both write-once and rewritable formats, whereas DVD rewritable refers only to rewritable formats.

Like CD-Rs, DVD recordables use dyes. Depending on the intensity of the laser, the reflective property of the dye on a particular spot will determine whether it is a peak or a valley representation from pressed DVD. Dyes give the data side of a disc a distinct color. Dyes are also the reason playback is not guaranteed. Their reflective properties are not as good as with stamped DVDs that commonly have aluminum as the reflective layer.

Recordable DVDs are divided into three incompatible camps:

DVD-R/DVD-RW (DVD "dash")

An internal DVD writer capable of burning either dash or plus discs

First DVD recordable format released in the market. Developed by Pioneer and backed by the DVD Forum. Has broader playback compatibility than the "+" especially with much older players. The dash format uses a "land pre-pit" method[1] to provide 'sector' address information.

DVD+R/DVD+RW (DVD "plus")

Developed by Philips and Sony with their DVD+RW Alliance. The "plus" format uses a more reliable bi-phase modulation technique[2] to provide 'sector' address information. Introduced after the "-" format.

DVD-RAM

As RAM stands for Random Access Memory, it works more or less like a hard-drive and was designed for corporate back-up use. Can only be read in drives that are DVD-RAM compatible. DVD Forum backs this format.

Multi-format drives can read and write more than one format; e.g., DVD±R(W) (DVD plus-dash recordable and rewritable) is used to refer to drives that can write/rewrite both plus and dash formats, but not necessarily DVD-RAM. Drives marked, "DVD Multi Recorder" support DVD±R(W) and DVD-RAM.

DVD recordable media are sold in two standard sizes, a standard-sized 12cm size for home recording and computer usage, and a small 8cm size (sometimes known as a miniDVD) for use in compact camcorders.

DVD write-once formats

DVD rewritable formats

Speed

Drive speed Data rate Disc write time Equivalent CD rate Reading speed
1× 11.08 Mbit/s 1.385 MB/s 53 min 9× 8×–18×
2× 22.16 Mbit/s 2.770 MB/s 27 min 18× 20×–24×
4× 44.32 Mbit/s 5.540 MB/s 14 min 36× 24×–32×
5× 55.40 Mbit/s 6.925 MB/s 11 min 45× 24×–32×
6× 66.48 Mbit/s 8.310 MB/s 9 min 54× 24×–32×
8× 88.64 Mbit/s 11.080 MB/s 7 min 72× 32×–40×
10× 110.80 Mbit/s 13.850 MB/s 6 min 90× 32×–40×
16× 177.28 Mbit/s 22.160 MB/s 4 min 144× 32×–40×
18× 199.44 Mbit/s 24.930 MB/s 3 min 162× 32×–40×
20× 221.60 Mbit/s 27.700 MB/s 2 min 180x 32×–40×
24× 265.92 Mbit/s 33.240 MB/s 2 min 216x 32×–48×

Notes:

Capacities

See also: DVD#Capacity

Most DVD±R/RWs are advertised using the definition of 1 Gigabyte = 1,000,000,000 bytes instead of the more traditional definition of 1 GB = 1,073,741,824 bytes = 1 Gibibyte.[3] This can be confusing for many users since a DVD advertised as having 4.7 GB (4.7 billion bytes) may show up on their device as only having 4.38 GB.

Format Decimal Capacity Binary Capacity
DVD±R 4.70GB 4.38GiB
DVD±RW 4.70GB 4.38GiB
DVD±R DL 8.55GB 8.15GiB
DVD-RAM 4.70GB 4.38GiB
MiniDVD 1.46GB 1.39GiB
MiniDVD DL 2.66GB 2.54GiB

Longevity

See also: Optical_disc_recording_technologies#Longevity

According to a study published in 2008 by the Preservation Research and Testing Division of the U.S. Library of Congress, most recordable CD products have a higher probability of greater longevity compared to recordable DVD products.[4]

References

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