Flight flown August 23, 1941 by Woltz Studios, Inc., for the U. S. Dept. of Agriculture, Agricultural Adjustment Administration. Photos numbered CG-1B-3 through CG-1B-175. Scale not given. Stereoscopic coverage. Only indexes are georeferenced.
Boone County (Ill.) (W 88°56′--W 88°42′/N 42°30′--N 42°09′)
Illinois State Geological Survey
147 remote-sensing images, .98 gigabytes, average file 6.84 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.