Lab 7 - Introduction to Photogrammetry

Goals and Objectives
The purpose of this lab is to introduce the class to photogrammetry techniques and stereoscopy. Part one involves looking at scales and measurement as well as relief displacement, part two involves creating and looking at stereoscopic images, and part three involves orthorectification.

Part 1
For part one we looked at images of Eau Claire, WI in Erdas Imagine. Using the measurement tool and hand rulers, we measured actual images and calculated perimiter, as well as relief displacement. With displacement something like a smoke stack may appear at a more oblique view (side view), with relief displacement, we find the principle point of the image and measure to the object, calculating displacement and correcting.

Part 2
For this part we looked at stereoscopy. We created an anaglyph image of Eau Claire, which requires 3D glasses to view. Using this image we can visualize easier elevation and buildings. In order to create this image, we used a digital elevation model to produce ground control points.

Part 3
For this part of the lab we looked at orthorectification. Using Erdas Imagine Lecia Photogrammetric Suite (LPS), we created an accuate set of ground control points to rectify an image.