University of Illinois Library

1408 W. Gregory Drive


Urbana, IL, 61801


Aerial Photographs of Illinois Counties Repository

History from a Bird's Eye: Illinois Aerial Photographs

A Prospectus for Creating a Digital Archive

April 14, 1997

Support for this project is provided by:

The Illinois State Library, Bridget Lamont, Deputy Director
The University of Illinois at Urbana-Champaign Library,
Robert Wedgeworth, University Librarian

Prepared by:

Beth Sandore, Coordinator for Imaging Projects, Digital Library Research Program
Jenny Marie Johnson, Head, Map & Geography Library,
Douglas Johnston, Director, Geographical Modeling Systems Laboratory and Associate, Professor, Landscape Architecture

The University of Illinois at Urbana-Champaign

Table of Contents


60,000 of the earliest aerial photos produced for the state of Illinois are in imminent danger of perishing unless steps are taken to digitize and preserve the data that they contain and to make them accessible to a broad audience. This archive, stored at the University of Illinois Library, is an invaluable resource for scholars, citizens, and the business community, because it provides the only remaining footprints of historical land and resource usage in Illinois. This proposal requests support to pursue a pilot project to digitize a representative sample of aerial photos from the collection, to create a demonstration database using an innovative combination of text and geospatial searching features that would be accessible across the state through the World Wide Web. The proposal seeks to build upon the Library’s rich existing base of information services and programs that serve citizens and agencies in Illinois at all levels, and to enable critical technology transfer between the academic and the business community by partnering with Scantech Color Systems, Inc., of Champaign, Illinois.

Narrative Description

The most comprehensive collection of aerial photographs of all 102 counties in the state, dates back to the 1930’s. This collection, held by the University of Illinois Library, is invaluable to the needs of researchers and citizens in the state of Illinois because it provides a dynamic history of the geographic features of Illinois in this century when both geographic and social features were rapidly changing. Unfortunately, this collection of aerial photos is rapidly deteriorating due to normal public handling, and storage in less than optimal conditions. Further, the negatives for these photographs no longer exist. Within a few years, many of the older photos will disintegrate, or will be so badly deteriorated that they cannot be used. A permanent, reproducible archive of these photographs is needed—one that will preserve at the highest resolution all of the picture information possible, and one that will make copies of this information easily accessible across the state to all interested Illinois users.

Currently, place and time limit access to printed aerial photographs; they may be used in the Map and Geography Library during regular business hours only. Retrieval of the photography is labor intensive. Users identify the photographs they require using photo-composite indexes and then wait while Library staff pull the requested items. Often Library staff is insufficient to pull the photographs immediately, and users are asked to return the next day to inspect their selections. We are able to supply high-quality photocopies to distant users but in order to do so the users must fax sufficient identifying information so that staff can locate the appropriate site and retrieve the correct photography. Users must expect a delay of a week, or longer, between the submission of their request and the receipt of copies from the University’s Photographic Services Division.

Early this year Champaign-based Scantech Color Systems, Inc. approached the Library and expressed an interest in digitizing approximately 60,000 of the aerial photos in the archive. Scantech’s business strengths include considerable expertise with high quality graphic printing and digitizing, using high resolution, state-of-the-art equipment. The Library and several state agencies have worked successfully with Scantech in the past several years to digitize a number of high resolution aerial photos and other graphic materials. We have established guidelines and standards for the production of high resolution digital images of these photos, and Scantech is eager to demonstrate to the library and archival community at large that these guidelines are appropriate for use in preservation and access efforts on a national level.

Through the funding from the Illinois State Library, the Library, the Geographical Modeling Systems Laboratory and Scantech Color Systems, Inc. intend to begin a pilot project to create a prototype image database with 270 images of aerial photos from Will County, produced in 1939 and in 1954. This project will produce a working database with an interface that enables users to search for particular areas of the state using conventional text and geographic coordinate point descriptors, as well as an innovative graphical location search. Once the prototype is completed, support is needed to create materials that will help to publicize the project and to achieve the desired level of funding and cooperation necessary to create an archive with all 60,000 images.

Statement of Objectives

The goal of the pilot project for which this support has been provided is to create an image database of 270 images that can be searched by using traditional text and geographic coordinate pairs, as well as by using spatial locations enabling the user to visually indicate the area to be searched by means of highlighting an area. The objective is to demonstrate a compelling example of a working and scalable prototype for a large-scale image database project with flexible and user-friendly searching options. After the pilot database is completed, a project report shall be prepared, and publicity and outreach materials shall be developed that will enable us to garner support to launch the full-scale database and search interface construction. The specific plan of work is described in the sections below.

Project team:

  • Beth Sandore, Coordinator for Imaging Projects
  • Jenny Marie Johnson, Head, Map & Geography Library
  • Doug Johnston, Director, Geographical Systems Modeling Laboratory, Assoc.
  • Prof., Landscape Architecture Dept., Research Scientist, NCSA
  • Bob Venable, President, Scantech Color Systems, Inc.
  • Michael Smith, Systems Manager, Scantech Color Systems, Inc.

Proposed time frame:

4 months, beginning immediately upon receipt of funding

Scope of work:

Approximately 270 photos of Will County, from the years 1939 and 1954 have been selected for the pilot project. Will County was selected for several important reasons. First, it enables the analysis of change in two areas—the urban area around Joliet and the rural surrounding areas. Several geographic features also pose interesting subjects for change analysis—the Des Plaines River, a munitions plant, and several other industrial developments.

The work of the pilot project shall be shared among the project participants. Approximately 270 photos will be inventoried, indexed, and cataloged by staff in the Map & Geography Library. The group records and the item-level indexing information shall be entered into a relational database program. The photos of Will County from 1939 and 1954 shall then be scanned by Scantech Color Systems, Inc. Image filtering and adjustment, as well as the generation of multiple resolutions, will be performed by Scantech. The images shall then be delivered to the University of Illinois and loaded into online storage. The images may be stored on a Library or a GMS (UIUC Geographical Modeling Systems Laboratory) server, depending on which is more convenient to the project development. The relational database of text indexing shall be mounted by the Imaging Laboratory staff on a Library server. For the prototype, it is likely that lower resolution images may be delivered through the Web interface. Digital images of the scanned photos will be registered using existing GIS (geographic information systems) tools in the GMS Laboratory. Registration is the process by which an aerial photo is "anchored" or assigned a specific location in geographic space. It involves assigning a number of geographic coordinate points to a photo using existing GIS data that is accessible in the GMS Laboratory. Registration is critical because it ensures that comparisons between aerial photos of the same area for different years will be geospatially accurate.

The project team shall develop the design specifications for a straightforward text and spatial search interface. Elements of design and retrieval technology that are under development at the University of California at Santa Barbara for their NSF/ARPA/NASA Digital Libraries Initiative project will be employed wherever possible. Further, the implementation shall use commercial database building tools developed by ESRI, the developers of the internationally renowned Arc/Info GIS software, to produce a database that is searchable over the Web. The interface design shall be coded and implemented by staff in the GMS Laboratory. The prototype system shall be made accessible on the Web from a University of Illinois server at the end of the pilot project.

At the close of the pilot project, the project team shall prepare a report, to be disseminated on the Web, and on a number of levels across the state for review and response. Local, county, and state government agencies that now use geospatial information as well as aerial photos will be targeted for distribution.

Advisory committee:

The project team shall benefit greatly from regular advice and review of their progress. Therefore, we recommend that the University Librarian establish an advisory committee, comprised of the University Librarian, the project team, state, county or local government agencies that use aerial photos and geospatial information, and representatives from the Graduate School of Library and Information Science, the Geography Department, and other state, county, or local government agencies, including the the Illinois State Geological Survey. The members of the advisory committee shall review the final product as well as provide information and advice as needed during the course of the pilot to prepare for the full-scale project.


A digital archive of aerial photography will inaugurate a new way of accessing the collection of photographs. Using the World Wide Web as a search and delivery mechanism will remove the constraints of place and time. The indexes and data will be available anywhere and anyplace the Internet is available. Users will be able to search the database using text terms such as "airport – Will County – 1939" or by feature names, "Joliet" or "Des Plaines River." They will also be able to enter Public Land Survey descriptions, "Township 25N, Range 2E, Section 19," and latitude/longitude coordinate pairs. Geographic searches on a digital photo-composite index using bounding rectangles or buffered points will take advantage of geographic information systems (GIS) capabilities. GIS will also make it possible for users to add "reference layers" such as county boundaries and highway networks to the digital composite index as assistance in determining location. Once an area has been selected, the system will present a list of images to the user for display selection if more than one image meets the search criteria , or if only a single image is applicable it will be displayed. Users will be able to print the images from their screen, and an option to request data transmittal will also be available. Although other United States research institutions have scanned aerial photographs, none of the existing projects proposes such an in-depth treatment, producing a rich information resource.

Collaborative Efforts (internal and external) and Need for the Project

There are two compelling needs to establish this archive—preservation of a crumbling resource, and the provision of greater and more flexible access to digital surrogates of the photographs to a growing user community. No other archive like this exists, and the opportunity to preserve this one will be lost within the next few years. Further, a digital archive will provide greater access using means that are currently not possible with the print photos and their indices to these materials for the Illinois government, business, and public communities. Currently, there are over 2,000 uses of the aerial photo archive per month. The photos are used by many different groups for numerous purposes. For example, an environmental scientist would use the photos to analyze how the availability of natural resources (e.g., wetlands) in a particular area had changed over time, and what effect that change had on the surrounding physical environment. The photos are particularly useful because they reveal the dramatic population increases around metropolitan areas from the 1930’s through 1950. Many state and government agencies concerned with the environment, natural resources, transportation, social services, and population make use of this type of collection. With the current trend toward making geographic information systems available over the World Wide Web, this project would provide a unique and complementary resource to other online files such as Illinois state agency databases, census and population data, and legislative information systems.

Similarly, several converging interests create the ideal conditions for this collaborative effort. The Library and the GMS Laboratory are equally interested in providing access to the image archive, with complementary approaches using text indexing on the one hand, and geographic feature indexing on the other. Scantech Color Systems, Inc. and the Library are keenly interested in spearheading a digitizing project that implements the standards and guidelines that we have established, so that a significant contribution can be made to the national conversation about digital imaging standards for the archival and preservation communities.

Impact and Assessment

Because this project will be integral to the information operations of many state, county, and city government agencies, it is anticipated that a significant amount of time will need to be spent in contact with these organizations about their interest, their needs, and how these can be met within the scope of the project. Impact will be measured by the record of how many and what types of users connect to the pilot database, and what type of information they use. This information will be easily collected using World Wide Web server logs, which automatically keep records on each page that is displayed in a Web site. The encouragement of the preparation of funding proposals to various state and federal government agencies, as well as private sources, will serve as another assessment of the success of the pilot database project.

Other Support

The Library, the GMS Laboratory, and Scantech Color Systems have each pledged cost share to accomplish this project. Scantech’s cost share alone ($8100 in scanning services) amounts to roughly half of the proposed budget for the project.

After the pilot project Scantech Color Systems is willing and interested to provide the support to digitize the 60,000 images. However, further support is needed in order to process the collection and to create the Web interface and retrieval software, as well as to store and archive the data. The additional support needed to complete the project will be considerable, up to $500,000 or more.