A set of 254 technical drawings of the People's Photometer for the Sierra Nevada Observatory, Granada, Spain. They were originally housed in three rolls labelled 'XD S Nevada People's Photometer' and include drawings of sizes V, W, X, Y and Z, mixed size sheets, and parts lists. The People’s Photometer was designed in the 1970s by Richard Bingham of the RGO and five were built for various observatories throughout the world, including Sierra Nevada.

From 1976, the Institute of Astrophysics of Andalusia (IAA) had used the facilities of the Mohón del Trigo Observatory (OMT) in Sierra Nevada (Granada, Spain), its main line of research being the photometric study of variable stars. The OMT was equipped with a 32-cm Cassegrain-type KYOTO reflecting telescope and the main measuring instrument was a photoelectric photometer. The OMT received guest astronomers from other institutions. In particular, close collaboration was established with the RGO, with frequent exchanges of staff in both directions. As a result of that collaboration, in 1977 an agreement was signed between the IAA and RGO to locate and jointly use a 75 cm telescope at a new site in Sierra Nevada (Loma de Dílar). An additional agreement was made with the Nice Observatory who offered a second telescope of 60 cm, leading to the creation of a building with two domes of 5 m and 8 m respectively.

The new Sierra Nevada Observatory building was completed in 1981 and the two telescopes were installed. Following a period of testing and modifications at RGO Herstmonceux, RGO transferred the Steavenson Telescope over from Herstmonceux and installed it in the 8 m dome. A general-purpose photoelectric photometer (‘People’s Photometer’) was installed alongside the telescope. The Steavenson Telescope and People’s Photometer were used at the Sierra Nevada Observatory from 1981-1989.

The drawings of the Sierra Nevada People’s Photometer in this series were produced by the RGO Drawing Office from 1968-1976 (bulk of the series) and in 1978, 1982 and 1987.