Off-nadir viewing allows for the creation of stereo images and the corresponding calculation of DEM. For example, the Space Imaging (SI) System has the ability to collect imagery in both a fore and aft direction along the orbital track. This feature will enable collection of high-quality stereo imagery within tens of seconds. This capability allows the SI system to create accurate DEM (90% LE) of 3.0 meters with ground control and 7.0 meters accuracy without ground control.
