File names of digital images may be developed from the title of a project, the title of a collection or a collection number, or from the title of the object itself. The file names are based on relevance to a project or to the object. Metadata for the digital images or files will capture pertinent data such as creator, dates, etc. Recommendations include a two to three character prefix that designates a clear association with a specific project.
Examples that meet the standards listed:
Willa Cather Archive
Western Waters, The Platter River Basin in Nebraska
All file identifiers for files stored on CD-ROMs should be compliant with ISO-9660:1988, and its relevant extensions mentioned below.
cc.0123456789.tif (17 characters in length)
File identifiers (often referred to as filenames) can be up to 30 characters in length, including:
- The file name (before the file extension)
- The dot separator(s)
- The file extension
(56 characters in length)
Length of file path, including file identifier, cannot exceed 255 characters. File names may include the following characters: A-Z, a-z,".", "_", "-" (period, underscore, and hyphen)
"Pic.0001.c-2_small.tif" would be a valid file name.
"Picture 3 of 40.tif" is not a valid filename because it contains illegal spaces.
Alphabetical characters in file identifiers should conform to the Rock Ridge Interchange Protocol (RRIP). RRIP extends ISO-9660:1988, while remaining completely compliant with it.
Numerical characters are allowed in file identifiers.
File Name Protocol
- Digital images are stored in the TIFF file format. Derivatives may include the following: JPEG, JPEG2000, GIF, PNG, and PDF.
- Digital image files stored on CD-ROMs should include master TIFF files and may also include derivatives created in support of a project.
- Information on content of CD-ROMs should be maintained for easy access to original master images stored on them. Currently in Archives and Special Collections this is kept on the Digital Imaging Database.
- In addition to digital images, the metadata on each image file should be retrieved from the Digital Imaging Database, saved in an XML or a delimited text format and burned onto the CD-ROMs as well. The database software allows export of specific records. This ensures that metadata for images exist on the storage media.
- CD-ROMs should be tested to ensure that the files can be retrieved.
- Store vertically.
- Do not touch reflective surface of disc.
- Do not bend.
- Store in archival sleeves, or jewel cases.
- Temperature conditions should remain between 41 and 72 degrees Fahrenheit.
- While the long-term effect of ambient room lighting is unknown, generally it is recommended that CD-ROMs be stored in a box or other enclosure.
- Do not write on the CD-ROMS, unless you use a CD-safe marker, and even then only mark on the clear plastic hub where there is no data.
- Do not apply adhesive labels.
- Avoid cleaning discs, unless the disc is unreadable or obviously very dirty. Wipe from the center of the disk outward, NOT in a circular spiral around the disc.
Caring for CD-ROMs
"Digital Conversion Methodologies," Jill Koelling, Nebraska State Historical Society