Exclude – excludes the raster DEM from the i-model

Full size – publish the raster DEM as a full resolution attachment to a local copy of a raster image.

Reduce Size – creates a reduced size version of the DEM as a raster attachment

The variable MS_RASTER_DOWNSAMPLING_PREFSIZE_FORIMODEL controls the size in MB of the reduced size Raster DEM. The default is 5.