Overview

The IMAX camera system consists of the camera, magazine, lens, power filter, and power cable. Seven lenses are available, and four are usually flown on a mission. A tape recorder and 2 microphones are used for audio recording. Two 150-watt cages photoflood lights are used to provide sufficient lighting for filming operations. The camera body is stored in a double locker, and two and a half additional lockers are used for storing auxiliary IMAX equipment.

For external photography, the camera may be gimbal mounted to the orbiter aft starboard window or the starboard overhead window. The aft starboard window has a direct attachment via Velcro to the gimbaled mount. The gimbaled mount attaches to the overhead mount via Velcro. The overhead window mount is installed in the orbiter with support pins and thumbscrews designed for the overhead window interface. The gimbaled mount allows panning and tilting with adjustable motion damplers. The overhead window mount bracket stows in the window shade bag on the middeck.

In-flight operations

Crew interaction with the IMAX camera entails the loading and unloading of film magazines, mounting of different lenses, selection of exposure, and positioning of the camera for the various types of scenes required.

On a typical IMAX mission, Earth scenes may be shot with ASA 25 film, using the 40mm lens for wide-angle views and the 60mm and 110mm lenses for closer views of specific Earth features. Similarly, activities in the payload bay can be filmed using the 30mm, 40mm, 60mm, and 110mm lenses. In-cabin scenes may require ASA 250 film and the 30mm lens. The crew positions photoflood lights in the middeck and flight deck for interior filming. A stereo cassette sound recorder and two microphones are also used by the crew to record on-orbit activities.

Camera body

• 65mm, single-lens reflex design
• 15 perforations per frame, horizontal pull-across
• Format: 2.07- x 2.77-inch aperture size, 1.34:1 aspect ratio
• 155 shutter; 1/56 sec exposure time
• Bayonet-type lens mount
• 30-volt variable speed dc motor (6 to 36 frames/sec)
• Power consumption: 300 to 500 watts
• Film travels at 336 feet/minute (5.6 feet/second) at 24 frames/second (3.5-minute filming time per roll of film)
• Two-thirds stop light loss from beamsplitter
• 1000-foot capacity magazines (1100 with polyester base film)
• Film: 65mm motion picture standard

Size

• 11 inches high, 11 inches wide (plus magazine), 20 inches long, plus lens, with 1000-foot magazine
• 85 pounds with lens and 1000-foot magazine

Viewfinder system

• Full reflex viewing via beamsplitter
• Magnifier - Engaged by pushing slide forward; normal viewing with slide fully backward
• Diopter adjustment

Lenses

All lenses are equipped with IMAX heavy-duty bayonet mounts, front element support cages, and focus levers

30mm Zeiss f3.5 (fisheye)

139-degree horizontal angle and stops to limit focus to 17 inches to infinity

40mm Zeiss f4

82-degree horizontal angle with external limiting ring to prevent lens from being mounted on camera when gimbaled mount is in short position

50mm Zeiss f2.8

69.7-degree horizontal angle with external limiting ring to prevent lens from being mounted on camera when gimbaled mount is in short position

60mm Zeiss f3.5

60-degree horizontal angle with ultraviolet (UV) filter on back of lens

100mm Zeiss f3.5

39-degree hroizontal angle with no. 85 filter on back of lens

110mm Zeiss f2

35-degree horizontal angle with UV filter on back of lens. Focus limited to a range of 6.5 feet to infinity. Alternate to 100mm lens

250mm Zeiss f.56

16-degree horizontal angle with no. 85 filter on front of lens. Also with stops to limit focus from 20 feet to infinity. External limiting ring to prevent lens from being mounted on camera when gimbaled mount is in short position

Author: Ursula Callaway
Curator: Terry McDonald
Responsible NASA Official: James Clement
(Note : This page copied from http://shuttle.nasa.gov/sts-71/pob/sts71/imax/fastfax1.html )