OHADP: The Oklahoma Historical Aerial Digitization Project

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What is the Oklahoma Historical Aerial Digitization Project?

The Oklahoma Historical Aerial Digitization Project (OHADP) started in 2007 as the Archival Photo Imaging Project, a Special Project in the Underground Injection Control (UIC) Department of the Corporation Commission. Before 2007, aerial photos were acquired and scanned on a case-by-case basis. However, Charles Lord, the UIC Manager, used to be a field inspector for the Corporation Commission and recognized the benefits of having historical aerial photography in the field. In November 2007, Charles wrote a grant request for $7,000 to purchase a DR-9080C Canon Scanner and $7,000 for a temporary worker’s salary to scan all available aerial photos at the time.

When the grant expired there was no end in sight for the aerial photo project, so Patricia Billingsley, head of the Corporation Commission Brownfields Program at the time, found funding in the Brownfields grant for the project, since the Brownfields program made use of the photos to research responsible parties for cases and to conduct Phase I Environmental Site Investigations.

Today, the project is funded by the UIC Program and the Brownfield Program.

The OCC has gathered and scanned hard copies of aerial photos from the Oklahoma Department of Libraries, the Oklahoma Department of Environmental Quality, and the Oklahoma Geological Survey. We currently have photos scanned and georeferenced from 1937 to the 1980s.

An employee scans acquired photos (usually 9” x 9” hard copies) at 300 dpi and saves them as JPEGs.

Next, GIS specialists in the office georeference (but do not georectify or orthorectify) the photos using county roads, trees, small streams, buildings, and surface features (excluding waterbodies) as references. All photos are georeferenced with at least three control points and as little compression as possible.

Then, OCC staff upload georeferenced images to our data portal and  Aerial Viewer , below.

1. Download individual georeferenced photos directly from the viewer above.

2. Send a hard drive to get all the photos.

If you would like all the georeferenced and not-yet-georeferenced photographs that we currently have, please send an Open Records Act request to the Commission's Office of Public Information:

Mailing Address Matt Skinner Oklahoma Corporation Commission -- Office of Public Information Jim Thorpe State Office Building -- Room 311 - C 2101 N. Lincoln Blvd. Oklahoma City, OK 73105 The message should say something like:  Mr. Skinner, Under the Oklahoma Open Records Act, I am requesting the OCC's historical aerial imagery. I understand I need to deliver an empty hard drive of size 2 TB or greater to Madeline Dillner or Colin Brooks to hold the photos.

Since the 1930s (and sometimes earlier), historical aerial photos were taken of the ground by aircraft equipped with mapping cameras (see below). The photos were taken either vertically, with the camera pointing straight down off the side of the plane at the ground below, or obliquely, with the camera pointing at an angle towards the horizon. Most oblique photos were either taken at 30 degrees (“low oblique”) or 60 degrees (“high oblique”) from vertical (Fig.2). Oblique photos are useful for seeing the skylines of cities and changes in elevation, but vertically-taken aerial photos can be placed together into a photo mosaic similar to today’s aerial imagery in viewers like Google maps. This trait makes them extremely valuable to anyone interested in studying how a landscape has changed over time.

To gather photos for the entire state of Oklahoma for one year, the USDA (usually) hired a private company out of Oklahoma City or Tulsa to fly in north-south (and sometimes east-west) flights over each county and take pictures out of a plane at regular intervals. There is approximately a 60% overlap between consecutive photos in a flight, and about 20-40% overlap between adjacent flights, so that the photos may be viewed stereoscopically to appear three-dimensional (pic below).

Most photos are taken between a 1:20,000 and 1:60,000 scale (i.e. 1 centimeter on the photo is 200-600 meters on the ground of the photo area). Photos taken at a 1:20,000 scale generally cover 4 sections (i.e. 1/9th of an Oklahoma township).

You can credit the Great Depression for historical aerial photos in the US. On May 12, 1933, President Franklin Roosevelt authorized the creation of the USDA Agricultural Adjustment Act as an attempt at helping the failing economy by regulating supply and demand of agricultural products. The Act primarily gave farmers subsidies in exchange for leaving some of their land fallow, and created the Agricultural Adjustment Administration to oversee subsidies. The Agricultural Adjustment Administration, now the Farm Services Agency, also oversaw the decadal collection of aerial photography of the US by county starting in the 1930s. The USDA used these photos to for agricultural planning and soil conservation efforts (Source: Illinois State Geological Survey. Illinois Historical Aerial Photography Collection History. 25 3 2013 .)

Each county and state made hard copy prints from the negatives provided by the USDA before sending the negatives to the National Archives. However, in the 1980s, many of the original negatives at the Archives had deteriorated to such a state that they were unusable, and were subsequently destroyed. The Archives made copies of them as negatives before disposing of them, but these copies are generally of poor quality. Consequently, the best existing records of these photos are the original prints and any copies made from them. Hard copy photos made from the original negatives are scattered around the United States, usually housed at state Geological Surveys, state universities, and county USDA Farm Services Agency offices. Viewing hard copy photos at these locations usually requires an appointment, since it takes time for libraries to pull photos for the requested area.

Do you have hard-copy aerial photos that need a new home?

 Let us know! The OSU Map Library might be able to take them off your hands and properly catalog and store them until they can be digitized. 

Disclaimer: This list was written in 2014 and has not been updated since then. Some states may have added or updated their projects since 2014.