Apollo TV camera

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Apollo Lunar Television Camera, as it was mounted on the side of the Apollo Lunar Module. Notice how it is stowed upside-down.

Television cameras used on the Apollo Project's missions (and later Apollo-Soyuz Test Project and Skylab missions) varied in design, with image quality improving significantly with each design. A camera was carried in the Apollo Command Module. For each lunar landing mission, a camera was also placed inside the Modularized Equipment Stowage Assembly (MESA) in Quad 4 of the Lunar Module (LM) Descent Stage, so it was capable of broadcasting the first steps of the astronauts as they climbed down the ladder of the LM at the start of the first moonwalk/EVA. Afterwards, the camera would be detached from its mount in the MESA, mounted on a tripod and carried away from the LM to show the progress of the EVA.

Contents

RCA slow-scan TV camera [edit]

Apollo 7 slow-scan TV

Apollo 7 and Apollo 8 used an RCA slow-scan camera.[1]

Westinghouse Apollo Lunar Television Camera [edit]

Lunar Module training mockup, showing relative position of deployed camera

In October 1964, NASA awarded Westinghouse the contract for the Lunar TV Camera.[2] Stan Lebar, the Program Manager for the Apollo Lunar TV Camera, headed the team at Westinghouse that developed the camera that brought pictures from the Moon's surface. The camera was first tested in space during the Apollo 9 mission in March 1969.[3] This is the camera that was used on Apollo 11, and captured humanity's first step on another celestial body on 21 July 1969.[3]

  • Usage: Apollo 9 (Earth orbit), Apollo 11 (lunar surface), Apollo 13, Apollo 14, Apollo 15, Apollo 16 (back-up to the lunar surface color camera, never used)
  • Transmitted Resolution (lines x samples): 320x250 (10 frame/s mode) / 1280x500 (0.625 frame/s mode, never used)
  • Sensor Resolution: Up to 650 TV lines vertically, horizontal resolution dependent on bandwidth
  • Bandwidth: 4 Hz to 500 kHz
  • Black and white
  • Sensor: 1 Secondary Electron Conduction (SEC) Tube
  • Analog FM transmission

The camera was built by Westinghouse, was 11 by 6 by 3 inches (280 mm × 150 mm × 76 mm) in size, and weighed 7.25 pounds (3.29 kg). It consumed 6.25 watts of power. It had four interchangeable lenses: "telephoto", "wide-angle", "lunar day" and "lunar night".

  • Photo of the high-quality SSTV image received from Apollo 11 at Honeysuckle Creek Tracking Station

  • Photo of the high-quality SSTV image before the scan conversion

  • Photo of the high-quality SSTV image before the scan conversion

  • Westinghouse camera on the Lunar surface during Apollo 11

Westinghouse Lunar Color Camera [edit]

  • Usage: Apollo 10 (CSM), Apollo 11 (CSM), Apollo 12, Apollo 13, Apollo 14, Apollo 15 (CSM), Apollo 16 (CSM), Apollo 17 (CSM)
  • Additional planned usage not implemented: Skylab Orbital Test flights prior to 1980. The ASTP cameras were modified to fly on the shuttle had the STS CCTV system not been available for the hoped 1979 maiden launch. by the time STS-1 flew the RCA CCTV system was already in place. (Crew Station Closed Circuit Television CCTV for Operational Flight Tests 08.06.1976)
  • Resolution: more than 200 TV lines (SEC sensor - 350 TV Lines in vertical dimension)
  • Scan rate: 59.94+ fields/s monochrome (color filters alternated between each field) / 29.97+ frame/s / 525 lines/fr / 15734.26+ lines/s
  • Color: Field-sequential color system camera
  • Bandwidth: Real 4.5 MHz / 2 MHz up to 3 MHz (transmitter limitation)
  • Sensor: Secondary-Electron-Conduction (SEC) Tube
  • Optics: 6x zoom, F/4 to F/44

This camera was based on the TV camera used on previous missions inside the CSM, with modifications to adapt it to the lunar environment.

During the early part of the first Apollo 12 EVA, the camera was inadvertently pointed at the Sun while preparing to mount it on the tripod. This action caused an overload in the secondary electron conduction tube (sensitive for low light conditions), rendering the camera useless for the remainder of the mission. The camera worked properly for about forty-two minutes. On later missions, while modifications were made to prevent such accidents, problems were encountered with image brightness and contrast (and sharpness – due to the camera overheating while stored, and operating in the MESA).

  • Apollo 10 TV image of Earth

  • Apollo 11 TV image

  • Westinghouse color camera on the Lunar surface during Apollo 12

  • Apollo 14 EVA image

  • Edgar Mitchell with the Apollo 14 camera

RCA J-Series Ground-Commanded Television Assembly (GCTA) [edit]

  • Usage: Apollo 15 (lunar surface), Apollo 16 (lunar surface) and Apollo 17 (lunar surface)
  • Resolution: more than 200 TV lines (SIT sensor - 600 TV Lines)
  • Scan rate: 59.94+ fields/s monochrome (color filters alternated between each field) / 29.97+ frame/s / 525 lines/fr / 15734.26+ lines/s
  • Color: Field-sequential color system camera
  • Spectral response: 350–700 nm
  • Gamma: 1.0
  • Sensitivity: > 32 dB signal to noise ratio
  • Dynamic range: > 32:1
  • Bandwidth: up to 5 MHz
  • Sensor: Silicon Intensifier Target (SIT) Tube
  • Optics: 6x zoom, F/2.2 to F/22
  • Automatic light control (ALC): average or peak scene luminance

Because of the failure of the camera on Apollo 12, a new contract was awarded to the RCA Astro division in Hightstown, NJ. The RCA system was a new, more sensitive and durable TV camera tube. The design team was headed by Robert G. Horner. The team used newly developed SIT, and the improved images were obvious to the public.

The system was composed of the Color Television Camera (CTV) and the Television Control Unit (TCU). These were connected to the Lunar Communications Relay Unit (LCRU) when mounted on the Lunar Roving Vehicle (LRV).

Once the LRV was fully deployed, the camera was mounted there and controlled by commands from the ground to tilt, pan, and zoom in and out.

  • GCTA transmission from the LRV

  • Apollo 15 television camera and high-gain antenna

  • Apollo 16 television camera. Notice the sunshade attached to the top of the lens, a feature first used on Apollo 16.

Usage [edit]

Cameras used, CM = Command Module, LM = Lunar Module

  • Apollo 7: RCA B&W SSTV (CM)
  • Apollo 8: RCA B&W SSTV (CM)
  • Apollo 9: Westinghouse B&W (CM)
  • Apollo 10: Westinghouse color (CM)
  • Apollo 11: Westinghouse color (CM), Westinghouse B&W (LM)
  • Apollo 12: Westinghouse color (CM & LM)
  • Apollo 13: Westinghouse color (CM & LM), Westinghouse B&W was a backup for LM (not used), LM camera was not used
  • Apollo 14: Westinghouse color (CM & LM), Westinghouse B&W was a backup for LM (not used)
  • Apollo 15: Westinghouse color (CM), RCA GCTA (LM), Westinghouse B&W was a backup for LM (not used)
  • Apollo 16: Westinghouse color (CM), RCA GCTA (LM), Westinghouse B&W was a backup for LM (not used)
  • Apollo 17: Westinghouse color (CM), RCA GCTA (LM)

See also [edit]

Notes [edit]

  1. ^ Apollo TV PDF
  2. ^ Steven-Boniecki (2010), p. 54
  3. ^ a b Steven-Bonicki (2010), pp. 80–81

References [edit]

External links [edit]
vehicles
vehicle
components
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