Digistar Generated Orrey 


Our Digistar Projector 

      The Abrams Planetarium Sky Theater uses an Evans and Sutherland Digistar projection system, which replaced the orginal Spitz ISTP projector installed in 1963. 

        The remainder of the Digistar system consists of a Sun Ultra for administrative tasks, a graphics co-processing system, and a number of monitors and control consoles. The system was installed in early 1993, and officially dedicated on September 14, 1994. The Digistar was upgraded into a Digistar II system during the summer of 1999.

         The Digistar projection system is the first planetarium projector based entirely on computer graphics display technology. The projector uses a 7-inch diameter monochrome flat-screen display, similar to a computer monitor. This screen lies horizontally, with the screen facing upwards.  A fish-eye lens above it to magnify the display and focus an image onto the hemispherical ceiling.  The projector produces a very high resolution (8000 x 8000 pixels) and extremely bright image, necessary to create a realistic starfield on the 15-meter diameter hemispherical ceiling. 

     The graphics processing computer which runs the projector takes numerical data from the files and manipulates them to compensate for the spherical distortion of the projection surface. It handles complex line or point art, and can transform shapes or perspectives rapidly, giving the illusion of motion.  So for example, the audience can be transported through the Solar System or out 200 light-years to distant stars of the Milky Way. 

Digistar Generated Space Station

Photo credit: Digistar Generated Orrey by Jenny Pon       
Space Station, Author Unknown