Historical Aerial Photography CD Roms 1951-1952

Scanned Aerial Photography from 1951-52 are available in digital format distributed on 2 CDs. Aerial photography of Rhode Island for 1951-52 was obtained from the collection of historic aerial photography on file at the RI Department of Administration, Statewide Planning Program. Original photography for the 1951-1952 was obtained from the Directorat of Intelligence, United States Air Force and consisted of 812 black and white 9"X9" photopositive prints at a scale of 1 inch = 1667 feet. These prints were produced from photo-negatives captured using standard airborne photogrammetric techniques between October 20, 1951 to November 22, 1951 and May 16, 1952 to June 13, 1952. This photography has not been orthographically rectified for photographic distortion associated with aircraft/camera orientation or ground elevation variation. Actual dates along with fight line and photo identification number were imprinted on each of the photographs.
To produce the digital images for 1951-1952 approximately every other print in the full 812 photos was scanned to provide 100% area statewide coverage. Scanning and compression of the images were done by contracted consultants in August of 2001. Individual prints were scanned on a flat bed scanner using commercially available software on microcomputers using Microsoft operating systems. The scanning rate selected was 400 dots per inch (dpi) with 8 bit gray (standard) and software default settings selected. Resulting scanned images were saved to Tagged Image File (tif) format. These tif images were then compressed at a 5:1 ratio with LizardTech MrSID Geospatial Encoder 1.4 to produce MrSid images(.SID). Images contained on these CDROM products have file names(shown as #H_###) corresponding to the combined two-digit flight line (#H) and three-digit photo number, imprinted on the photos. A table showing flight numbers, photo numbers, MrSid image file names and the year the image was taken is also included on this CDROM.
Indexing and copying of data to CDROM media was conducted at the Rhode Island Department of Administration, Statewide Planning Program in February 2002.
Two separate composite data sets of images were composed, one for Northern RI and one for Southern RI. The Northern data set consisted of 216 images and the Southern data set consisted of 181 images. This provided full coverage for the state with north/south photographic overlap allowing for individual towns to be contained on one of the two CDROM products. Tables showing flight numbers, photo numbers, MrSid image file names and the year the image was taken are also included on these CDROMs as Northern/Southern_RI.xls (MSExcel).

 

Software

For those who are not already GIS users or who lack the specialized software required for extended GIS analysis, we have included Lizardtech's MrSID GeoViewer. This program is also available for free over the world wide web and can be accessed at http://www.lizardtech.com/. Please consult the accompanying license for any questions concerning this program's usage.

If you do not already have Arcview or another application that supports the MrSID image format, you will need to install the MrSID GeoViewer software on your computer. 

MrSID GeoViewer is a very small installation. It requires only the following:

Windows

  • Microsoft® Windows 95/98/2000 or Windows NT® 4.0 with service pack 6 or greater
  • 200MHz PC processor
  • Minimum of64MB RAM
  • Internet Explorer 4.0 or greater, or Netscape® navigator 4.5-4.7

Power Macintosh

  • Apple® G3 or later
  • Mac® OS 9 or later
  • 20MB allocated to Web browser
  • 5MB hard disk space
  • Internet Explorer 5.0 or greater or Netscape® Navigator 4.5-4.

Additionally, please note that ESRI's Arcexplorer (2.0) supports the MrSID image format. Arcexplorer is a free GIS data viewer available from ESRI. For information about other GIS and image processing software with which to view MrSID images, please see http://www.lizardtech.com/.

About RIGIS

The Rhode Island Geographic Information System (RIGIS) is a consortium of government and private organizations employing computer and communications technology to manage and use a collective database of comprehensive geographically related information. The mission of the RIGIS is to monitor, coordinate, and provide leadership for activities related to the use of GIS technology within Rode Island, to support initiatives to implement or use the technology, and to manage and provide access to a common database of geographically referenced information.

The RIGIS database is maintained on a server at the University of Rhode Island's Kingston Campus, and at the Rhode Island Department of Administration in Providence. The Environmental Data Center within the Department of Natural Resource Sciences at the University provides on line access (web-browser only) to most RIGIS data via the Internet at www.edc.uri.edu/RIGIS. Data can also be provided on magnetic and optical media by request from the RIGIS coordinator at the RI Department of Administration's Statewide Planning program at rigis@admin.ri.gov.

RIGIS data are copyright protected and licensed for use by the RI Board of Governors for Higher Education. Restrictions include prohibiting the secondary distribution of RIGIS data without prior written approval.

RIGIS Contact Information:

John Stachelhaus-RIGIS Coordinator
RI Dept. of Administration/Statewide Planning
1 Capitol Hill
Providence, RI 02908

email: rigis@admin.ri.gov

telephone: (401) 222-6483