An archival DVD or archival gold DVD is the best option when choosing DVD as a storage format for digital information such as digital photographs, digital videos, and other types of digital files.
For DVDs, there are three basic formats:
Obviously, the read-only format cannot be used to store your own digital files. The DVD -RW or +RW discs can be erased which is not a great feature for longevity and tests have shown that the materials used in these discs are not very stable. Therefore, the -RW and +RW formats are not considered archival DVDs. Another type of erasable disc is the DVD-RAM disc, but this format is not in widespread use and little is known about its stability. For this reason, this format is also not considered an archival DVD.
That leaves the recordable DVD which comes in three formats: -R, +R, and a dual layer or DL version of the –R or +R formats. Tests have shown that the dual layer versions do not compare well to the single layer versions in terms of stability. For the DVD+R, although similar materials are used and generally similar stability with the DVD-R format exists, many DVD+R discs have compatibility issues. In other words, they do not burn or read well in a wide range of burners or readers. Therefore, the best option for an archival DVD is the recordable disc format.
Unlike the CD-R, there is no stable phthalocyanine dye used to store the digital information in recordable DVDs. Instead the dye is similar to an azo or cyanine dye and is usually blue or purple in appearance depending on the dye that is used. The DVD-R dye is less stable than the light green phthalocyanine dye used in archival CD-Rs. The metal reflective layer, which reflects the laser light back to the player’s detector after the dye layer is read in order to create a signal, is usually a silver alloy. Silver alloy is not very stable and can corrode over time. Therefore, to make an archival DVD, a gold metal layer is used as the reflective layer. Overall, this archival gold DVD media is not as stable as the gold CD-R primarily because of the less stable dye that is used.
The recordable disc color when viewed from the base is usually a bright blue or purplish-blue tone when a silver alloy metal layer is present as shown below.
When a gold metal layer is present the disc usually appears like the one shown below.
The largest manufacturer of this type of archival gold DVD is MAM (Mitsui Advanced Media) in the United States. Several other companies such as Delkin and Kodak purchase these MAM gold DVDs and rebrand them. The manufacturer of this media advertises that it will last 100 years. Whether this figure is accurate is not really important. What is important is that this type of DVD-R is the most stable available and should be used if an archival type DVD is desired.
Another type of disc available on the market that is advertised as archival is from Verbatim or Falcon. This DVD-R has two metal layers – a silver alloy metal layer to reflect the laser light and a gold metal layer as a protective barrier for the more reactive silver metal. Research to evaluate the stability or longevity of this type of disc is limited but it is anticipated that the stability is better than the average silver alloy only DVD-R, but not as good as the all gold disc. A quick summary of DVD-R stability from most stable to least stable is below.
Summary of DVD-R Stability
Even if an archival DVD is used to store digital files, it is recommended to always have a second copy of the information available on a different type of storage medium. Also, regardless of whether archival media is being used or not, the technologies to read the media eventually become obsolete and the information stored on such media will have to be transferred to another format if the information is to remain readable in the future.