Thursday, January 25, 2007

Historical Aerial Photography in the GCMC

Pictures of the Past: Aerial Photographs in the GCMC

GoogleEarth has popularized the use of aerial photography in research, and these images are becoming more common in everyday use. GoogleEarth is available on the computers in the GIS lab in the Geospatial Center & Map Collection. Digital images of current aerial photography for the state of Indiana is also available for download from the Indiana University GIS website. And the GCMC has digital access to the most recent aerial photography for Delaware County. But the Center is also an excellent resource for historic aerial photography from all over the United States and even parts of Australia.

Complete sets of aerial photography at 1:100-feet and 1:400-feet scales for Delaware County are available for research. The dates of the photography are 1974, 1979, 1982, 1985, 1987, 1992, and 1997. These sequential photographs are an excellent tool for viewing changes in the landscape of an area over time. Recently a graduate student in Architecture used four aerial photographs of the same site in Muncie dated at intervals of five years to study the development around her research site. The number of buildings added in each progressive photograph was quite dramatic.

Some development of Marion County can be studied using aerial photographs of the county in the GCMC. Two sets of aerial photographs at 1:100-feet scale from Marion County are available. The dates of these sets are 1985 and 1994.

The GCMC also has historic aerial photography in the 1:400 feet scale of other Indiana counties: Grant County, 1984; Hamilton County, 1985; Henry County, 1993; Madison County, 1985; Monroe County, 1993; and Randolph County, 1993. Smaller aerial photographs of other Indiana counties are also available as reference materials in the GCMC: Boone County, 1939 and 1955; Carroll County, 1938, 1939, 1951, 1952, and 1958; Pulaski County, 1938 and 1957; and White County, 1938, 1939, 1951, and 1958.

The GCMC also has historic orthophotoquad maps and orthophoto maps of most of the United States. Orthophotoquad maps are aerial photographs layered onto the USGS 1:24,000 topographic quadrangle maps. The orthophotomaps are usually color versions of similar maps. Most of these maps are 1:24,000-scale maps. The GCMC contains sets of maps from all but nine states--Arizona, Kansas, Kentucky, Montana, New Jersey, New York, North Dakota, Ohio, and Rhode Island. The GCMC has orthophotoquads from all other states. The sets of maps from Florida, Georgia, North Carolina, Texas, and Virginia are exceptionally thorough. The maps of Alaska include satellite image maps and radar image mosaic maps. (The image of the region of Ugashik is shown above).

The GCMC also houses sets of aerial photographs of parts of Australia. The largest coverage is of South Australia. A new (2005) set of topographic maps of New South Wales was recently added to the Collection.

With the exception of the smaller reference materials of Boone, Carroll, Pulaski, and White Counties, the entire collection of aerial photography may be checked out from the GCMC for two weeks. Please contact the GCMC with any questions about using historic aerial photography for research and learning.

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