Hitting save is not the final step: The care and feeding of digital files

Each WHO Content Provider is responsible for maintaining its own archival master files (the high-resolution files created by scanning or photographing original materials). Like the artifacts in a museum collection or the manuscripts in an archive, these digital files must be carefully preserved in order to ensure their longevity. In fact, although it may not seem like it, digital material is actually MORE fragile than printed paper or microfilm. 

 

Information created, stored, and accessed digitally is at risk for loss in two important ways: obsolescence and physical damage. Obsolescence can affect hardware, software, and even the arrangement of the data in a stored file, and it can occur in an alarmingly fast pace. Digital information is also vulnerable to physical threats. Like obsolescence, physical damage can occur to multiple components required to access digital information, namely hardware and media.

                                                                         --Digital Preservation Management tutorial, Cornell University

 

Because the large-scale digitization of cultural heritage materials is so new, and because technology changes so rapidly, it is impossible to recommend a single, permanent strategy for digital preservation. The Wisconsin Heritage Online Preservation Recommendations (or Word version) offer a tiered structure so your organization can choose, based on available resources, which level of preservation to consider during each step of the digitization process.

 

There are three key elements to a good preservation plan, and you should take these into consideration BEFORE you begin digitizing materials.

• Quality files and metadata. Scanning your original materials in a high-resolution, non-proprietary format helps ensure that your files will remain accessible and usable in the future. Well-organized, consistent metadata that follows a widely used scheme (like Dublin Core) helps ensure that your information can be located easily and migrated to other programs in the future, if necessary.
• Lots of copies. Save more than one copy of each file, and store the copies on different types of storage media and in different locations. 
• Regular monitoring, migration and upgrades. 

 

 

Physical Storage

Careful handling and storage of the CDs, hard drives, and other physical objects where your digital files reside is essential.

• "Selecting Storage Media for Long-Term Preservation," Digital Preservation Guidance Note 2, National Archives

• "Care, Handling, and Storage of Removable Media," Digital Preservation Guidance Note 3, National Archives

• Digital Storage Media, National Park Service Conserve-O-Gram
• "How to choose CD/DVD archival media," Patrick McFarland, Ad Terras Per Aspera blog
  

   

   

Improving the lifespan of CDs and DVDs

(from North Carolina ECHO's Digitization Guidelines, Chapter 6: Digital Preservation)

Always	Avoid	Never
Store media in controlled archival environment	Damage to the upper and lower surfaces and edges of the disk	Attach or fix anything to the surface of a disk
Store media in a jewel case or protective sleeve when not in use	Scratching and contact with surfaces that might result in grease deposits (e.g. human hands)	Write on any part of the disk other than the plastic area of the spindle
If using sleeves, use those that are of low-lint and acid-free archival quality	Exposing disks to direct sunlight
Wear gloves when handling the master disks

 

 

Read more about digital preservation . . .  

• Digital Preservation at the Library of Congress (National Digital Information Infrastructure and Preservation Program) and The Signal, the program's excellent blog

• Howard Besser, "Digital Longevity," Section IX in Handbook for Digital Projects: A Management Tool for Preservation and Access, Northeast Document Conservation Center, 2000

• David Rosenthal, "Requirements for Digital Preservation: A Bottom-Up Approach," D-Lib Magazine, November 2005 

• "Long-Term Management and Preservation," Introduction to Imaging, Getty Research Institute

• Digital Preservation for Museums, Canadian Heritage Information Network. Key points include:

• Ensuring each object in the digital collection is assigned a persistent identifier (e.g., develop a consistent system for naming your files)

• Develop a timetable for evaluating holdings (e.g., perform regular checks to make certain your digital files are still readable)

• "An Introduction to Digital Preservation," State Library of North Carolina's Digital Information Management Program via WebJunction

• Digital Preservation, Northeast Document Conservation Center