733667-001-011-0113

Federal Agencies Digitization Initiative Still Image Working Group — August 2010 In general, master files have the following attributes: a Maintain the essential features and information of the original a Represent the best copy produced by a digitizing organization, with best defined as meeting the objectives of a particular project or program a Represent digital content that the organization intends to maintain and manage for the long term a Are created primarily for the production of a range of copies used for specific purposes (such as derivatives and duplicates) a Document the image at the time of scanning, not what it may once have looked like if restored to its original condition Institutions may create one or more digital master copies depending on the nature of the originals and the intended purpose of digitization. Digitization should be done in a “use-neutral” manner, and should not geared for any specific output. If digitization is done to recommended image parameters and all other requirements as described in these Guidelines, we believe the master 1mage files produced should be usable for a wide variety of applications and outputs. If digitization 1s done to meet the alternative minimum image parameters and all other requirements, the master image files should be usable for many access applications, particularly for web usage and reproduction requests. Generally, given the high costs and effort for digitization projects, we do not recommend digitizing to anything less than the alternative minimum image parameters. This assumes availability of suitable high-quality digitization equipment that meets the assessment criteria described (see the section on Quantifying Scanner/Digital Camera Performance) and produces image files that meet the minimum quality described in the Guidelines. If digitization equipment fails any of the assessiment criteria or is unable to produce image files of minimum quality, then it may be desirable to invest in better equipment or to contract with a vendor for digitization services. SCOPE The focus of the Guidelines is on historical, cultural and archival materials. The scope is limited to digitization practices for still image materials only (e. g., textual content, maps, photographic prints and negatives). The Guidelines are intended to be informative, not prescriptive. We acknowledge that this document does not address the entire range of imaging quality parameters (such as noise, distortion, etc.), but these topics will be incorporated as the Still Image Working Group identifies recommendations in these areas. The Working Group has produced a “Gap Analysis” document that identifies and prioritizes digitization activities that are not currently defined within existing agency guidelines, or are not adequately addressed by existing guidelines. The Gap Analysis contains topics that the Working Group intends to investigate and provide as updates and recommendations in future versions of these Guidelines. The current Gap Analysis can be found on the FADGI website at: http://www.digitizationguidelines. gov/stillimages/documents/Gap.html. We hope to provide a technical foundation for digitization activities, but further research will be necessary to make informed decisions regarding all aspects of administrative, operational, and technical issues surrounding the creation of digital images. These guidelines provide a range of options for various technical aspects of digitization primarily relating to image capture, but do not recommend a single approach. The following topics are addressed in this document: s Digital image capture for still images — creation of master files, image parameters, digitization environment, color management, etc. 5 Color encoding accuracy — color space, color temperature for imaging and viewing, quality of linear vs. area arrays, and quality of different interpolation algorithms Technical Guidelines for Digitizing Cultural Heritage Materials: Creation of Raster Image Master Files 2