Aerial Photographs: Viewing the Changing Landscape of Colorado Aerial Photographs: Viewing the Changing Landscape of Colorado
Aerial Photographs: Viewing the Changing Landscape of Colorado
Aerial Photographs Home Search by Map Search by Geographic Keyword

About this Site

Print Collection

The Jerry Crail Johnson Earth Sciences and Map Library at the University of Colorado has a collection of aerial photographs taken from 1938 through the 1970s. The collection consists of about 20,000 photographs in print and on film and is largely un-indexed. The collection was originally a working collection used for teaching and research in the Geography Department. The Department of Geography's Staff Cartographer, James J. Robb approached the Earth Sciences Library in 1994 to house its restricted historic air photo collection upon the completion of the new library facility. The Cartography Lab worked closely with the Map Library through the transfer of the photographs, original index base maps, and database to the library in 2001.

Project

This project was conceived as a way to provide access to the photographs by digitizing and indexing them using a geographic information system. The project was funded through an IMLS (Institute of Museum and Library Services) grant administered through the Colorado Digitization Program as part of their Western Trails Project.

The Cartography Lab provided the first computer hardware and software, and developed a GIS methodology, which was the genesis of the existing system.

The project team used ESRI products ArcView and ArcMap to plot the center points of each photograph and to provide enhanced keyword indexing using the attribute table. The photographs were scanned at 600 ppi with 24 bit color, using the "Western States Digital Imaging Best Practices" as a guide. Metadata was created for the photographs by county and year. The website was developed using images and data exported from ArcMap. Geographic and keyword searching capabilities were developed using ASP and MySQL.

We plan to continue to scan and index the photographs, focusing on the area around Boulder and will add photographs and data on an ongoing basis. Please direct questions about this site, project, or the collection to the Map Library at maplib@colorado.edu.

Metadata

Machine-Readable Cataloging (MARC) bibliographic records were created for this project in the Online Computer Library Center (OCLC) database at an encoding level of 'I' (full-level cataloging), and exported to the University Libraries' local online catalog, Chinook. One collection-level record and a total of 22 set-level records were created, the latter of which describe flight lines of photographs by their county and year. For example, there is a bibliographic record for 'Boulder County, 1938' that describes the 121 digitized aerial photographs in that flightline. These original records were created using the Anglo-American Cataloguing Rules, the Library of Congress Rule Interpretations, the Library of Congress Subject Headings, and the OCLC Bibliographic Formats and Standards for MARC 21.

Metadata from the MARC records was semantically mapped then crosswalked into Dublin Core in accordance with the Colorado Digitization Program's (CDP) "Western States Dublin Core Metadata Best Practices, version 1.2"1 for inclusion in the CDP's Western Trails database2 and that of the Colorado Virtual Library3. Eventually, these Dublin Core records will also be harvested by the Open Archives Inititive (OAI) for its international database of academically-oriented digital resources4.

Team

The project team consisted of faculty in the University of Colorado Libraries:

Suzanne T. Larsen, Faculty Director, Jerry Crail Johnson Earth Sciences & Map Library (PI)
Christopher Cronin, Electronic Resources Cataloger
Anna Ferris, Cataloger
Katie Lage, Map Librarian
Holley Long, Digital Initiatives Librarian
Patrick Tally, Scanning Supervisor

As well as Student Assistants Geneva Mixon and Miranda Lavrakas, who did the indexing using ArcGIS.

We would also like to acknowledge Elisabeth Filar Williams, who conceived of the original project and wrote the original grant.