Flights flown between August 23, 1938 and September 3, 1938 by Park Aerial Surveys, Inc., for the U. S. Dept. of Agriculture, Agricultural Adjustment Administration. Photos numbered RU-21-1862 through RU-29-2552. Scale not given. Stereoscopic coverage. Only indexes are georeferenced.
Henry County (Ill.) / W0902600-W0895200 / N0413500-N0410900
Illinois State Geological Survey
538 remote-sensing images, 2.98 gigabytes, average file 5.67 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.
Mode of access: World Wide Web. System requirements: Plug-in or image viewer, ExpressView Browser plug-in available for download. System requirements for interactive map: Google Chrome best.