Flights flown between July 13, 1939 and September 4, 1939 by Midwest Aerial Surveys, Inc., for the U. S. Dept. of Agriculture, Agricultural Adjustment Administration. Photos numbered BWR-1-3 through BWR-6-64. Scale not given. Stereoscopic coverage. Only indexes are georeferenced.
DeKalb County (Ill.) / W0885600-W0883500 / N0420900-N0413800
Illinois State Geological Survey
366 remote-sensing images, 1.33 gigabytes, average file 6.53 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.