The RMSC Strasenburgh Planetarium Star Theater: some technical details
Projection dome size
Diameter 65 feet (19.8 meters). Height at highest point 40 feet 6 inches above floor level.
225, all facing approximately forward, first installed 1985. The previous seats, which faced toward the center of the theater, featured tilt-swivel mounts and loudspeakers in the headrests. They were removed because the concentric arrangement was not suitable for film shows, and because maintenance requirements on the old seats had become excessive.
Zeiss model VI, installed 1968, the Planetarium's original instrument. Click on the link to "The Star Projector" for more information.
8-perf 70mm, installed 1995.
Four full-color 500mw diode laser scan heads plus one 1.6-watt blue-green system for atmospheric beam effects, upgraded in 2014. Powered by Pangolin laser software.
In an innovative configuration designed and installed by Strasenburgh Planetarium technical staff, three Panasonic PT-D4000U DLP video projectors create a seamless image using Dataton Watchout video compositing software. The Watchout image in the Strasenburgh Planetarium Star Theater covers almost half the circumference of the dome and reaches about one-third the dome's height, creating an image format like a huge windshield in front of the audience. Our configuration as of February 2014 provides a rectangle of approximately 2728 by 768 pixels, allowing us to project images from still cameras aboard the International Space Station and Space Shuttle at nearly full width with full resolution. Even larger images, such as mosaics from the Hubble Space Telescope, can be explored by panning and zooming.
An advantage of our "windshield" image format compared to the fulldome systems found in some other planetariums is that no imagery is projected behind our audience, where it would merely "bounce back" stray light into the main viewing area, impairing contrast and saturation.
A fourth video projector, dubbed the "Lookout" projector, is pointed backward at a hemispherical mirror to create all-sky motion effects such as clouds and streaming stars. The Dataton Watchout software feeds imagery to this projector as well as to the three main video projectors.
A fifth video projector, aimed at the central viewing area in front of the audience, is used for Power Point presentations and open captioning for films.
The Watchout production software makes it possible to create and update shows quickly. All star and laser shows at RMSC Strasenburgh Planetarium are produced in-house.
Slide projectors (still in occasional use!)
Panorama system: Two banks of nine 35mm slide projectors create 9-segment panoramas spanning 270 degrees of dome azimuth.
All-sky system: Two banks of six 35mm slide projectors create 6-segment all-sky images covering the entire dome.
Multi-image system: fifteen 35mm slide projectors create partially overlapping images in the central viewing area in front of the audience.
Speakers: Six channels of sound are fed to speakers behind the dome in positions at the left rear, left front, bottom center, top center, right front, and right rear. Two additional channels are fed to left and right sets of "cove" speakers arrayed around the springline inside the dome.
Playback equipment: Soundtracks for shows are usually played from Tascam DA-88 digital tape decks or from data files on hard drives.