Apollo 15 Mission
Mission Photography
Camera Equipment | Orbital Photography | Surface Photography
The Apollo 15 mission was designed to obtain the most extensive quantity and variety of photography of any mission thus far. There were several different varieties of photographic equipment, both on the surface and in orbit. The camera equipment operated on the lunar surface or in the LM by astronauts Scott and Irwin included three 70-millimeter Hasselblad Data Cameras (HDC, LM1, LM2), a 16-millimeter Data Acquisition Camera (DAC), and a color TV camera (LM4), or Lunar SurfaceTV camera. The main photographic tasks during orbit were performed with the Mapping Camera System and the Panoramic Camera, which were in the SIM bay. Various tasks were also accomplished using four command module cameras: a 70-millimeter Hasselblad electric camera, a 16-millimeter Maurer DAC, a 35-millimeter Nikon, and a Westinghouse color TV camera.
Lunar Surface TV Camera
The RCA television camera (LM4) used on the lunar surface could be operated from three different positions--mounted on the LM modularized equipment storage assembly (MESA), mounted on a tripod and connected to the LM by a cable, and installed on the LRV with signal transmission through the lunar communication relay unit. While on the LRV, the camera was mounted on the ground-controlled television assembly. The camera could be aimed and controlled by the astronauts or remotely controlled by personnel in the mission control center. Color was achieved by using a rotating disc driven by a 600-rpm motor. Lunar color scenes were scanned, field sequentially, and down-linked serially to the Manned Space Flight Network. Video was received and recorded from lunar distance at any of the three Deep Space Stations.Mapping Camera System
The purpose of the mapping camera system was to obtain photographs of high geometric precision of all lunar surface features overflown by the spacecraft in sunlight. This camera system consisted of a 76-millimeter Fairchild mapping camera (SIM3) using 5-inch film, a 3-inch stellar camera using 35-millimeter film, and a laser altimeter. The electrically operated system was powered by 115 volts, 400 Hertz alternating current (AC), and 28 volts direct current (DC) spacecraft power.The laser altimeter, when operating independently, gave altitude data at a frequency of three data points per minute when the mapping camera was off and approximately 2.5 points per minute when the camera was on. The altimeter malfunctioned during the orbital mission, and no data were obtained after revolution 38. A complete girth of the Moon with the altimeter was acquired on revolution 15/16; sporadic data were recorded otherwise. About 30% of the planned altimeter data was obtained.
The stellar camera was mounted on an axis at 96° from that of the mapping so that it photographed the sky while the mapping camera photographed the lunar surface. Any photography designated "stellar" refers to this photography, except that discussed as Special Photography and Experiments. The film cassette containing stellar and mapping photography was removed from the SIM bay by the command module pilot during trans-Earth trajectory and was returned to Earth in the command module.
Panoramic Camera
The optical bar panoramic camera consisted of three major assemblies: (1) the roll frame assembly, which basically provided the platform for the rotating lens system; (2) the gimbal structure assembly, which rocked the roll frame assembly back and forth to provide for stereo photography and to compensate for the forward motion of the vehicle; and (3) the main frame assembly, which attached to the vehicle and provided a platform for the film transport system as well as for the roll frame and gimbal structures. Two mirrors folded the 24-inch (610-millimeter) focal length into a more compact configuration, and the camera had a relative aperture of f/3.5 and field of view (FOV) of 10.77° (20 kilometers of surface and 100 kilometers altitude). The lens was rotated about an axis parallel to the SM, and a capping shutter opened during the time the lens passed through a 108° arc (320 kilometers of lunar surface at 100 kilometers altitude) below the vehicle. The light admitted was focused through a variable width slit from a minimum opening of 0.38 millimeters to a maximum of 7.6 millimeters. The slit width and scanning rate (rate of rotation of the lens) established the photographic exposure time.The camera was mounted on rails that were attached to shelves in the SIM. During camera operation, the SM positive X axis had to be in the direction of the velocity vector. The film takeup cassette was removed from the panoramic camera by the command module pilot during trans-Earth trajectory, and was returned to Earth in the command module.
70-millimeter Hasselblad Electric Camera
The 70-millimeter Hasselblad electric camera was used during rendezvous and docking operations and during translunar coast and trans-Earth coast to photograph the Earth and Moon. It was also used to acquire dim-light, earthshine, and UV photographs (using a 105-millimeter lens). This Hasselblad camera had a motor-driven mechanism that was powered by two sealed nickel-cadmium batteries. The mechanism advanced the film to the next frame and cocked the shutter whenever the camera was activated. The normal 80-millimeter lens could be easily replaced with a 105-millimeter, 250-millimeter, or 500-millimeter lens.35-millimeter Nikon Camera
The 35-millimeter Nikon camera was mounted in the righthand rendezvous window and periodically made time exposures during the dark portion of the lunar orbit. The purpose of the experiment was to determine whether, and to what extent, reflection from dust particles at the Moulton point contributes to the gegenschein. The gegenschein region was not acquired but, instead, the camera photographed another part of the Milky Way as a result of a translation error in coordinates from the ground.Westinghouse Color TV Camera
A Westinghouse color television camera, used in the command module, could be handheld or bracket-mounted. The scanning rate for the camera was the commercial 30 fps, 525 scan lines lines per frame. The resolution of the camera was 200 TV lines per picture height with an aspect ratio of 4:3 and a range or operation from 5 to 12,000 f-c. A 5-centimeter black-and-white video monitor, which could be Velcro-mounted on the camera or at various locations in the command module, aided the crew in focus and exposure adjustment. A camera ringsight also aided in directing the lens at the desired target.
Both the service module and the command module performed orbital photographic tasks. The main photographic tasks during orbit were performed with cameras in the scientific instrument module (SIM), located in the service module. In the SIM bay were two photographic packages: the mapping camera system and the panoramic camera. The service module tasks were to obtain high-quality metric/mapping photographs and high-resolution panoramic photographs in both stereoscopic and monoscopic modes.
Orbital Photography - Photographs taken from lunar orbit provide synoptic views for the study of regional lunar geology. The photographs were used for lunar mapping and geodetic studies and were valuable in training the astronauts for future missions.
Metric/Mapping Camera Photography - The mapping/metric photography was performed using the Mapping Camera Subsystem, which included the metric camera, the stellar camera, and the laser altimeter. This equipment was mounted in the SIM bay section of the CSM. This photography was collected to be used for establishing a unified selenodetic reference system, for photomapping at scales as large as 1:250,000, and for synoptic interpretation of geologic relationships and surface material distribution.
The Mapping Camera was operated on 16 passes during the period of lunar orbit. The camera was also used twice during trans-Earth coast, the first time for 2 hours and 29 minutes, and a second time for approximately 13 minutes. Camera operation was near normal. The deployment mechanism exhibited an anomaly; however, this problem had no effect on acquisition of the photography.
Inflight contingencies required rescheduling of planned photography, resulting in a loss of approximately 10% of the preplanned photography. A total of 3481 frames were taken, but only 2491 frames are considered usable. Some frames are blank as a result of exposure during operation with the laser altimeter on the darkside.
Panoramic Camera Photography - The 610-millimeter (24-inch) ITEK panoramic camera obtained high-resolution panoramic photographs, in both stereoscopic and monoscopic modes, of the lunar surface during the Apollo 15, 16, and 17 missions. The camera provided 1- to 2-meter-resolution photography from an orbital altitude of 111 kilometers (60 nautical miles). The panoramic camera was located in the SIM bay of the service module. Panoramic photographs supported photographic data for the other command service module cameras and for the SIM experiments, scanning the lunar surface from lunar orbit, providing greater area coverage and higher resolution for given regions.
Two panoramic camera photographs of Dawes Crater. The 60-centimeter-focal-length lens of the camera provides high-resolution photographs of the lunar surface from orbital altitudes. Approximately one-fourth of the 11.4-centimeter × 114.8-centimeter frame is reproduced; the area shown includes terrain south of the CSM at viewing angles between 15° and 45° of the vertical. High-resolution photographs such as this support continuing studies of lunar surface features long after the completion of the last Apollo flight.
Because of the extended capability of the life-support equipment and the new mobility provided by the lunar roving vehicle, the Apollo 15 astronauts explored a much larger area than had been possible on previous missions. The 67-hour stay time of the lunar module on the lunar surface accommodated three EVA periods for a total of almost 38 man hours of lunar surface activity. While on the surface, the crew took 1151 photographs with the Hasselblad cameras. Major photographic tasks were to record surface activities and document sample retrieval.
Surface Activities - Photography supporting the lunar surface activities was designed to document the deployment of experiments, to augment crew observations, to expand descriptions during the traverses, and to record the effects of the interaction between Apollo equipment and the lunar surface.
Sample Documentation - The Apollo 15 landing site is between the Apennine Mountain Front and Hadley Rille. The objectives of the mission, in order of decreasing priority, were description and sampling of three major geologic features: the Apennine Front, Hadley Rille, and the mare. Approximately 78 kilograms of rock and soil samples were collected, and 1152 photographs were taken with the Hasselblad cameras. The photographic surveys taken during this mission were designed to record the surface characteristics of the sample areas, the retrieval of the sample, and the location of the sample at the time of collection.
Summary
New camera systems that were mounted in the scientific instrument module (SIM) bay of the service module provided a major photographic capability that had not been available on earlier missions, manned or unmanned. Additional camera equipment available for use within the command module (CM) and on the lunar surface increased the photographic potential of the mission over previous manned flights. The Apollo 15 crew returned an unprecedented number of photographs. The 61-centimeter-focal-length panoramic camera exposed 1570 high-resolution photographs. Mapping camera coverage consists of 3375 frames from the 7.6-centimeter-focal-length camera; a companion 35-millimeter frame exposed in the stellar camera permitted precise reconstruction of the camera-system orientation for each photograph. Approximately 375 photographs were exposed between trans-Earth injection and the deep-space extravehicular activity (EVA). The Apollo 15 crew also returned approximately 2350 frames of 70-millimeter photography, 148 frames of 35-millimeter photography, and 11 magazines of exposed 16-millimeter film. Mission photography was accomplished from the command module, from the lunar module, during EVAs, and from the SIM during five days in lunar orbit.