Occurrence

When I load my Aerial raster imagery or DEM/DTM surface grid into Discover3D, it is only displayed at a low resolution and is pixelated when I zoom in.

It looks fine and full resolution in Mapinfo Professional.

Solution

Discover3D has limitation on the resolution of individual image branches (layers). These can be set under Tools>Options>Size, but they have practical limits even on high end 64bit computers

In practice these are -

Rasters Images - 4096 x 4096 pixels
Surface Grid - 10 000 x 10 000 cells.

To workaround this limitations multiple "tiles" of a larger dataset can be loaded easily.