Apollo TV camera

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Apollo Lunar Television Camera

TV cameras used on the Apollo (and later ASTP and Skylab) missions varied in design, with image quality improving significantly with each design. For each mission, the camera was 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.

[edit] Westinghouse Lunar Color Camera

Usage: Apollo 10 (lunar orbit), Apollo 11 (lunar orbit), Apollo 12 to 14
Resolution: ~175x~175
Lines per frame: 262
Frame rate: 20 fps (60 fields, with each color filter used for 3 fields, resulting in a 20 fps color video)
Bandwidth: 2 MHz
Sensor: Secondary-Electron-Conduction (SEC) Tube
Colour: Field Sequential Camera

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

During the early moments 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 vidicon tube, rendering the camera useless for the remainder of the mission. On latter missions problems were encountered with image brightness and contrast.

Apollo 10 TV image of Earth

Apollo 11 TV image

Apollo 12 EVA TV image

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

GCTA transmission from the LRV

Usage: Apollo 15 to 17
Resolution: ~ 200 lines
Frame rate:
Colour: Field Sequential Camera
Spectral response: 3500–7000 angstroms (350–700 nm)
Gamma: 1.0
Sensitivity: > 32 dB signal to noise ratio
Dynamic range: > 32:1
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.