Four (4) original large-format vintage gelatin silver prints on glossy paper from NASA's Second Lunar Orbiter mission, November 18-25, 1966. The photographs are designated II-197M, II-197H1, II-197H2, and II-197H3, lower left. A total of 215 sets of photographs were planned for the second orbiter mission in 1966, each consisting of one medium-resolution image and three high-resolution images of the same area. The four complementary images in group 197 show the Maestlin G crater and its smaller binary crater. The area in the main image slightly to the southeast of Maestlin G was designated as Landing Site 5 for the Apollo 11 and 12 missions, a backup site should the need arise. Unframed. Sheets measure 24" H x 20" W. 

Note: "Five Lunar Orbiter missions were launched in 1966 through 1967 with the purpose of mapping the lunar surface before the Apollo landings. All five missions were successful, and 99% of the Moon was photographed with a resolution of 60 m or better. The first three missions were dedicated to imaging 20 potential lunar landing sites, selected based on Earth-based observations. 

The Lunar Orbiters had an ingenious imaging system, which consisted of a dual-lens camera, a film processing unit, a readout scanner, and a film handling apparatus. Both lenses, a 610-mm narrow angle high-resolution (H) lens and an 80-mm wide-angle medium resolution (M) lens, placed their frame exposures on a single roll of 70 mm film. The axes of the two cameras were coincident so the area imaged in the HR frames were centered within the Medium Resolution frame areas. The film was moved during exposure to compensate for the spacecraft velocity, which was estimated by an electric-optical sensor. The film was then processed, scanned, and the images transmitted back to Earth.

Lunar Orbiter 2’s mission was to photograph 13 primary and 17 secondary landing sites for the Apollo program in the northern region of the Moon’s near side equatorial area." (Source: NASA.gov)

Each in very good condition with slight wrinkling, predominately on edges, a few corners with handling creases.