 Exploring imagery and elevation data is a very important course for those who desire to make effective use of imagery and DEMs in GIS analysis. Imagery has become widely available from so many sources, from satellites such as Landsat and Sentinel, to digital aerial photography, to very detailed imagery from unmanned aerial systems. The number and size of pixels, the spatial resolution, defines your ability to identify distinct features on the ground. Even casual users of imagery are aware of how this affects the utility of image datasets in real-world applications. On the other hand, even many experienced GIS users are less aware of the finer points related to the positional accuracy of imagery pixels and how this positional accuracy is achieved. It is quite possible, for example, for features within a high-resolution image to be in the wrong place in the world. For example, if lane markers on a highway that are clearly visible in an aerial photograph are not in the correct location due to hills in the terrain, the GPS location of a car traveling along that lane may not appear to be between the lane markers in map display. Students in this course will learn how elevation models are created and how they're used to improve the positional accuracy of imagery by correcting for relief displacement. They'll also perform slope, aspect, and hydrologic analyses and overlay imagery on elevation models to create realistic 3D visualizations. Many students comment that this class was one of the most immediately useful courses in the curriculum and that they were able to put what they learned to use right away at work or in their research.