Digital ortho, georeferenced or georectified aerial photography imagery is the standard delivery for nearly every aerial survey project involving engineering, surveying or GIS projects. Terra Flight Aerial Imaging routinely provides custom Digital Ortho Aerial Imagery to a large customer base to suit their needs. These customers typically require new and higher resolution imagery than is available from dated stock internet sources.
What is a Digital Ortho Image? An orthophoto is a digital vertical aerial photograph that has been orthorectified (or geometrically corrected) by removing the distortion. The ortho corrected image now projects a uniform and very accurate scale across the entire image. The ortho corrected digital image is then fully georeferenced by assigning a geo-coded (X and Y) coordinate value to every pixel in the aerial image. Digital Ortho Aerial Imagery is used in engineering and or survey data software programs such as AutoCAD, ArcView or ArcGIS, among many others.
Terra Flight Aerial Imaging uses specialized photogrammetric ortho software such as Leica Imagine to process the raw aerial imagery into a digital ortho image. All of our projects meet or exceed National Map Accuracy Standards such as FGDC-STD-008-1999.
What is the difference between these images? Click here to read more.
Examples – CAD Program Overlay
The examples below illustrate a digital ortho image opening as an image layer in an AutoCAD program. In the examples below there are approximately six layers of CAD data shown.
In this example this project was a flood study for a city in southwest Texas that covered approximately 75 square miles.
This example shows a petrochemical facility located in the Houston, Texas area.
This example shows a petrochemical facility located in Beaumont / Port Arthur, Texas area.
This digital ortho image was required by a survey company client which required a new aerial image to be overlaid with new survey data in an AutoCAD environment. In this example, the boundary survey is overlaid perfectly with the digital ortho image. This site has a substantial number of building structures and nursery related infrastructure improvements. These improvements are clearly shown in the digital ortho image without the need of surveying the very complex outlines of every existing structure.
This site is approximately 4.5 square miles or 3,000 acres.
The digital ortho Image used in this example is of an active landfill. This surveying and mapping client, which specializes in landfill mapping, required the digital ortho image to overlay the 2’ generated contour lines and planimetric data as part of the delivery items. The ultimate delivery of this data included volumemetric calculations to determine the amount of compressed fill that was added over a period of time.
The purpose for this ortho image was to generate a new site map for an existing city zoo facility. This facility is undergoing constant upgrading and expansion and the requirement of an updated map became necessary along with a new survey. We provided our client with a new digital ortho image of the site to overlay all of the new and existing survey data and facility maps to generate a new site map.