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.
Seats
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.
Star projector
Zeiss model VI, installed 1968, the Planetarium's original
instrument. Click on the link to "The Star Projector" for more information.
Film projector
8-perf 70mm, built by Pioneer Technologies (later acquired by Iwerks Entertainment), installed 1995.
Laser projectors
5-watt argon, 1-watt krypton, with in-house system for color
separation and pattern production
Video systems
In an innovative configuration designed and installed by
Strasenburgh Planetarium technical staff, three commercial-off-the-shelf 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 December 2009 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 is inexpensive and easy to
use, so we can create and update shows quickly. All star and laser shows at
RMSC Strasenburgh Planetarium are produced in-house.
Slide projectors
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.
Sound system
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.