Flights flown between August 24, 1939 and September 21, 1939 by Midwest Aerial Surveys, Inc., for the U. S. Dept. of Agriculture, Agricultural Adjustment Administration. Photos numbered BWS-1-1 through BWS-4-81. Scale not given. Stereoscopic coverage. Only indexes are georeferenced.
DuPage County (Ill.) (W 88°16′--W 87°55′/N 42°00′--N 41°41′)
Illinois State Geological Survey
236 remote-sensing images, 721 megabytes, average file 3.1 megabytes
Scanned from 7 x 9 contact prints (nominal scale ca. 1:20,000) on Crosfield 646IE drum scanning system at 750 dpi. Quality assurance target not published but available by contacting the Illinois State Library Map Dept. MrSID files compressed at a target ratio of 12:1. Uncompressed TIFF images on cd available from the Illinois State Library Map Dept.