SciAn is a Science Animation program that runs on SGI and IBM RS6000 computers. It can read a variety of file formats for the rendering of molecular structures and densities. It is very window/icon oriented so once you have a data file in the proper format, you need only work with the objects.
SciAn Homepage/DocumentationThere is other software available for the visualization of scientific data, however, these are much more complex to work with. Programs like Explorer and AVS have a much wider variety of viewing techniques and controls. The price of this higher control is the complexity involved with even the simplest of operations. The quality of the final image nomally depends on the quality if the hardware of the machine. Currently Explorer comes with the high end SGI graphics machines, while AVS must be purchased as third party software.