About Photogrammetry

Photogrammetry History

The science of photogrammetry started early in the 20th century with simple mechanical devices to orient two photographs relative to each other, and the resulting model relative to the ground.The technology progressed to the use of sophisticated optical-mechanical systems, but still using essentially the same concepts.

The late 60’s / early 70’s saw the introduction of computers using the concept of analytical photogrammetry in order to control precision instruments to orient and measure the stereo models. This results in very high precision due to precise numerical calculations as opposed to mechanical approximations. This method improved speed, efficiency, and accuracy and allowed transition from paper-based maps to digital maps.

 

SR 90 Hyak to Easton Project

The image below will make it easy to see how the photogrammetric design work is overlaid onto the orthophoto (corrected aerial photos) imagery. You will also see in inserts at different scales and a survey control point on the ground.