Flights flown between July 31, 1939 and August 3, 1939 by Midwest Aerial Surveys, Inc., for the U. S. Dept. of Agriculture, Agricultural Adjustment Administration. Photos numbered BWZ-1-3 through BWZ-6-70. Scale not given. Stereoscopic coverage. Only indexes are georeferenced.
Lee County (Ill.) / W0893700-W0885600 / N0415400-N0413500
Illinois State Geological Survey
467 remote-sensing images, 2.86 gigabytes, average file 6.27 megabytes
Scanned from 7 x 9 contact prints (nominal scale ca. 1:20,000) on Crosfield Celsis 6200 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 6:1. Uncompressed TIFF images on cd available from the Illinois State Library Map Dept.