Flights flown between August 14, 1939 and September 10, 1939 by Midwest Aerial Surveys, Inc., for the U. S. Dept. of Agriculture, Agricultural Adjustment Administration. Photos numbered CK-1-2 through CK-5-83. Scale not given. Stereoscopic coverage. Only indexes are georeferenced.
Macoupin County (Ill.) (W 90°09′--W 89°42′/N 39°32′--N 39°00′)
Illinois State Geological Survey
459 remote-sensing images, 3.02 gigabytes, average file 6.73 megabytes
Scanned from 9 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.