Processes, Standards & Methodology

Introduction: A digital collection consists of digital objects that are selected and organized to facilitate their access and use. Functional digital collections include metadata used to describe and manage them. The following metadata schemes and content standards were created for the Percent for Art Digital Collection. Where practicable, standard cataloging conventions were used—specifically, those recommended through AACR2 and other generally recognized cataloging standard resources and organizations. Cataloging art and visual materials is significantly different from book cataloging, however. A beneficial attribute of an art-focused digital collection is that it allows the description of visual materials to be expanded in ways that MARC format cataloging does not; thus there are times when new local standards are necessary. Subject classification was derived from the Library of Congress Subject Headings. A structured vocabulary related to art terms and concepts was created utilizing Getty's Arts and Architecture Thesaurus.

Technical Information

A digital preservation strategy starts at creation time of a digital object. Each of the original sources materials is prepared for digitization. Slides are cleaned before the acquisition stage with a cleaning cloth or canned air as needed. Documents are handled with gloves or as applicable related to their value and condition. Each source object is scanned and saved as an archival TIFF copy, from which a JPEG version of the image is derived for collection viewing. All of the images are stored on a separate server. Archival master images vary in range depending on their bit depth and relative dpi to format size. Slides are digitized using a Nikon SuperCoolScan 5000 ED slide scanner. Photographs and documents are acquired using flatbed scanners—an Epson Expression 10000 XL, usually, with a few exceptions on a UMAX PowerLookIII.

Scanning/imaging software for all devices is Silverfast AI 6.0. Initial settings are assigned by format. For photographs and miscellaneous color images, we use 48>24 bit color. Documents and grayscale images are assigned 16 bit. Small photographs (5 x 7 and less) are scanned at 1200 dpi, while settings for larger photographs are adjusted to 600 dpi. 35 mm slides are scanned to 4000 dpi on the long side to optimize results.

The imaging specification for digital collection resources was designed to produce images optimized for display on the Internet. The originals were cropped using Adobe Photoshop CS2 to include only the artwork and relevant contextual objects and/or physical setting. After reviewing a representative sample of the documents, bit size, "Hue/Saturation," and "Unsharp Mask" adjustments were developed in Photoshop and subsequently applied to the majority of images in order to attain a close tonal and color match to the originals. Level adjustment was performed manually, while recurring processes were automated using a set of Photoshop "Actions" that flattened, sharpened and resized the images. All delivery images were converted from Adobe RGB 1998 to sRGB IEC61966-2.1 colorspace.

Format Specifications

Photographs: Captured on flatbed scanner. Digital images in TIFF format are not resized, captured as 48>24 bit color, archived and saved. Photoshop used to reorient and crop image, set and neutralize shadow and highlight points, adjust levels, contrast and sharpen as needed. Second production TIFF saved. Color profile converted and resolution revised to 125 pixels. Longer dimension resized to 875 pixels; display JPEG saved at quality level 6.

Slides: Captured via Nikon slide scanner. Master TIFF iimage captured at 4000 pixels across the long edge, archived and saved. Photoshop used to reorient and crop image, set and neutralize shadow and highlight points, adjust levels, contrast and sharpen as needed. Second production TIFF saved. Color profile converted and resolution revised to 125 pixels. Longer dimension resized to 875 pixels; display JPEG saved at quality level 6.

Born digital images: Digital file enters Photoshop in RAW format. Imaging software used to convert RAW file to 8 bit RGB. Archived TIFF is saved. Photoshop used to reorient and crop image, set and neutralize shadow and highlight point, adjust contrast. Second production TIFF is saved. Color profile is converted, resolution set to 125 dpi and longer length resized to 875 pixels. Display JPEG is saved at quality level 6.

Textual documents: Scanned from originals using Silverfast AI 6.0 on UMAX Powerlook III, Microtek ScanMaker 9800XL or Epson Expression 10000XL flatbed scanners and saved as 16 bit grayscale or 24 bit RGB color TIFFS. Images are manipulated in Photoshop (CS or CS2), cropped, rotated, levels adjusted, and bit depth reduced. Omnipage Pro (version 14 or 15) is used to OCR 8 bit TIFFS and generate text files for full text access.

Standards & Workflows

The Percent for Art project was divided into four working stages. All standards & workflow documentation provided below have been saved in a file format known as an Adobe® Portable Document Format (PDF) file. In order to view PDF files, you will need Adobe Acrobat Reader for your Web browser. You may download the Adobe Acrobat Reader here.

 

 

Last Modified: June 24, 2008
Comments and questions to Digital Collections Administrator
Metadata Services and Digital Projects, University of Oregon Libraries