Category: Processing and quality
DEM (Digital Elevation Model)
A DEM is a raster representing elevation, used for terrain correction, hydrology, and orthorectification.
Also known as: elevation model
Expanded definition
A digital elevation model (DEM) stores elevation per pixel. DEMs are used to correct terrain effects in imagery (orthorectification), model shadows, and derive slope and aspect.
DEM quality and resolution matter. In steep terrain, a coarse DEM can leave residual geometric errors and can affect correction results.