SE Wisconsin Regional Planning Commission

SE Wisconsin Regional Planning Commission Providing full-service geospatial mapping services for Southeastern Wisconsin Regional Planning Commission for more than 15 years.

Illinois Tollway - High Accuracy Mapping

Illinois Tollway - High Accuracy Mapping AeroMetric has completed 36 miles of High Accuracy Mapping along a portion of the I-88 highway in Illinois.

U.S. Army Corps of Engineers: St. Louis District

U.S. Army Corps of Engineers: St. Louis District Providing digital mapping and related professional services to St. Louis District U.S. Army Corps of Engineers (USACE).

USGS 133: Urban Areas Initiative (Chicago)

USGS 133: Urban Areas Initiative (Chicago) Inventorying critical resources for disaster preparedness and homeland security. U.S. Geological Survey's 133 Urban Areas Initiative.


The digital orthophoto process transforms a vertical aerial photograph into the equivalent of a traditional map. Yet it retains the advantages of a photograph—visually displaying actual cultural and land features, and the built environment, rather than representing those features using symbols and lines.

How AeroMetric Produces an Orthophoto

1. Horizontal Corrections: The first step is to determine the exact camera orientation at the moment of exposure during the flight mission—the x, y, z of the camera lens center, plus the effect of aircraft pitch, roll and yaw upon the camera. These elements are derived directly with the use of Airborne GPS and IMU technology, or by means of ground control points analyzed photogrammetrically. This first step results in an image that is free of lens distortions, and is horizontally connected with a standardized scale.

2. Vertical Corrections: The second step involves using a DEM to vertically correct each pixel for the effects of relief displacement. This method depends on knowledge of the camera projective geometry, and the relationship between actual feature height and a predetermined vertical point of reference. The resultant image is an ortho-rectified image map that can be referenced to any known ground system.

3. Radiometric Balance: The final stage in the process involves radiometric and tonal balance correction so that all images blend well, and are naturally and aesthetically pleasing. This can be a challenge when imagery is collected in different lighting conditions on different days.

AeroMetric's Advantage

To help solve this radiometric challenge AeroMetric's own innovative tone-balancing software is used as the first step to providing uniform imagery. We then creatively select from our suite of commercial software programs to stitch together several individual orthophotos and generate seamless orthophoto mosaics.

Quality Assurance

The quality of a digital orthophoto is dependent upon the quality of each step in the process. For example, it is essential to start the process with good imagery and accurate input data, rather than proceeding, and trying to repair flawed imagery later. Because of our attention to quality outputs, AeroMetric will provide you with accurate and visually appealing orthophotography, and do so in your preferred data format.

Stay Informed

Please fill out the information below and we will contact you shortly.

Close this box


Enter the information below to stay up-to-date on all the latest Quantum Spatial news & events.

Close this box