Audio Recording and Moving Image Media: from Cylinder and Silent Film to Videotape and CDs
- What is the best type or brand of CD or DVD to purchase for long term storage of files?
- How long can I expect my CD and/or DVDs to last?
- I have audio and/or video on tape. Whom can I contact to transfer it to digital media?
- What is the best way to pack vinyl record albums for storage? For shipping?
The Library of Congress cannot recommend specific brands of CDs or DVDs, as we are generally prohibited from voicing preferences for particular manufacturers or vendors. In addition, we do not have conclusive evidence that one manufacturer is superior; there is a tremendous variety in the performance of various brands. That being said, initial evidence points toward the “gold” type of CD-R and DVD-R as being more durable than other types of CDs. Gold compact discs tend to be more stable, as the gold metal reflective layer does not oxidize; however, there is still a dye layer in gold CD-R and DVD-R recordable media that is susceptible to damage from light.
For more information, refer to the CD Longevity Research currently underway at the Library of Congress. Other studies include the article Electronic Media Collections Care for Small Museums and Archives (Canadian Conservation Institute [CCI]) and the article CD and DVD Longevity: How Long Will They Last? by Andy Marken.
CDs and DVDs, like anything else, deteriorate. The compact disc is a laminated system usually involving a reflective layer (where the information is stored in digital format) sandwiched between two polycarbonate layers. Manufactured or “read-only” CDs and DVDs are made from a stamped or molded plastic disc that imparts the information onto the reflective metallic layer. The actual metals used are proprietary information, so little is known about their exact physical composition. Recordable CDs and DVDs (CD-R and DVD-R) use a dye in combination with a reflective metal layer; a certain frequency of light alters the physical structure of the dye during the recording process, while another frequency “reads” the information. Since these dyes are affected by light, long-term light exposure can result in deterioration, as will fluctuations and extremes in both temperature and relative humidity.
The best approach for preserving CDs or DVDs is to keep them in a cool, dry environment in protective jewel cases. During handling, avoid touching the surface of the disc. Copying discs will also work as a preservation strategy; however, the copies should be regularly checked, since a recordable CD is less stable than a manufactured CD. Avoid writing on the surface of the CD or DVD. If marking is necessary, use a non-solvent based ink pen.
For more information, refer to the publication Care and Handling of CDs and DVDs: A Guide for Librarians and Archivists (Council on Library and Information Resources) and the article CD and DVD Longevity: How Long Will They Last? by Andy Marken.
The Library of Congress cannot recommend specific service vendors to digitize your audio and video collections, as we are generally prohibited from voicing preferences for particular manufacturers or vendors. The Association for Recorded Sound Collections (ARSC) maintains a directory of members who offer services for audio preservation and restoration, as well as ARSC members and non-members who offer equipment and supplies for audio preservation and restoration.
Vinyl records and other phonographic sound discs are susceptible to heat; therefore, protecting the discs from extreme heat during shipment should be the primary concern. Pack vinyl discs in strong boxes that can bear the weight of the discs, making sure to line packing material (foam, bubble wrap, etc.) on all six interior sides of the box. The discs should be placed in the box vertically with a strong upright support (for example, a few pieces of heavy duty cardboard, cut to the same size as the album cover) every few inches to prevent “slouching” of the discs during transport. Make sure to label the container with easily readable markings indicating the top of the box.
For more information, refer to the Library of Congress webpage Cylinder, Disc and Tape Care in a Nutshell.