This lecture was presented at the
3D Digital Documentation Summit held July 10-12, 2012 at the Presidio, San Fransisco, CA.
Archive of Digital Data for HABS, HAER, and HALS
"The NPS creates a variety of documents and records, such as inventory and monitoring plans, drawings, photographs, and conservation treatment records, to assist in the planning, management and preservation of cultural resources. Most of these, including many of 3D digital documentation products, are permanent records under the NPS Records Retention schedule, requiring the NPS to preserve them in some form. In addition, under NPS Director’s Order 19, cultural resource management records are mission critical, required for the management of the cultural resources within our parks, and must be permanently preserved. Programs such as HABS/HAER/HALS create large amounts of electronic data, such as point clouds, CAD files, and digital field photographs that constitute valuable field data permitting the verifiability of the final documentation.
Electronic records, particularly laser scanning and imaging technologies, present long-term preservation and storage challenges. Even technologies that allow for a file format with an open standard, such as a point cloud conversion to ASCII, are still problematic because of inadequate IT infrastructure within that does not facilitate storage, migration and retrieval of digital data. Moreover, the Library of Congress (LOC), which houses traditional print HABS/HAER/HALS documentation and is the sole repository designated in the National Historic Preservation Act for engineering and architectural documentation produced for Sections 106 and 110 compliance, has collections policies prohibiting proprietary software and storing of data directed at a limited audience that would prevent the inclusion of many of the products being discussed at this summit.
Despite on-going efforts for several years, resolving these issues has proven problematic. The LOC and HABS/HAER/HALS are jointly exploring born digital equivalents to large-format film photography that is currently required to meet Secretary of Interior Standards, but the lack of standards within the commercial photography community as well as the high cost of large-format digital capture and storage makes writing standards difficult. Likewise, the lack of industry standards for technologies such as laser scanning, and the reliance on proprietary software and file formats, discourages the LOC from accepting these files into its collections. Because of this, HABS/HAER/HALS uses laser scanning as a tool to create traditional print drawings on vellum or mylar that can be permanently preserved at LOC, rather than producing laser scans as an end product in and of itself. HABS/HAER/HALS also is consulting with the National Archives and Records Administration (NARA) to determine if some of these file types can be preaccessioned into the Electronic Records Archives (ERA). Currently the file formats that can be preaccessioned are extremely limited, but we hope that NARA can accommodate more in the future. With no other public repository for these files, NPS has few alternatives but to maintain its own digital records and confront the technological and financial challenges this presents. NPS has no IT preservation system in place to prevent the gradual decay of storage media over time and the corruption of electronic files, also known as bit rot. Creating a digital storage system modeled on Open Archive Information System (OAIS), which runs file integrity checks to guard against data loss, would require a significant investment in infrastructure and money at a time when the NPS is facing a multi-billion dollar maintenance backlog for its historic structures.
In sum, 3D digital documentation can produce some exciting products that were not previously possible, but we must recognize that the challenges associated with digital preservation put all of these products at risk unless we find solutions that permit their responsible and economical curation and preservation."
In other words (maybe), this government agency is unable to store certain images digitally because it lacks the technical capability and is burdened by government regulations and it's own existing (2012) limited awareness and practices.
In 2012 (when this doc was written) it wasn't even aware that Sony would for theatrical presentation (not just popular distribution) digitize Lawrence of Arabia, revealing startlingly more detail than could be seen in the distributed 70mm prints.
The solution to "bit rot" involves multiple backups on multiple media (HD, tape, thumb drives, DVD, cloud etc etc) tc...but govt agencies are stuck with regulations and political interests that prevent obvious solutions. As well, of course, they avoid the most obvious solutions, which boil down to mass distribution.