Flights flown between June 16, 1938 and July 9, 1939 by Midwest Aerial Surveys, Inc., for the U. S. Dept. of Agriculture, Agricultural Adjustment Administration. Photos numbered BXL-1-1 through BXL-5-26. Scale not given. Stereoscopic coverage. Only indexes are georeferenced.
Winnebago County (Ill.) (W 89°24′--W 88°56′/N 42°30′--N 42°10′)
Illinois State Geological Survey
329 remote-sensing images, 1.93 gigabytes, average file 6 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 12:1. Uncompressed TIFF images on cd available from the Illinois State Library Map Dept.