Calibration of SQM-L photometers for the NixNox project

Abstract

Twelve SQM-L night sky photometers have been tested and analyzed to determine their internal precision and differences in response. These photometers will be used by amateur astronomers around Spain, under the supervision of the Sociedad Española de Astronomía (SEA), to locate and characterize sites with dark skies well suited to perform astronomical observations (NixNox Project). A simple experimental setup has been built to obtain zero offsets for each photometer in order to correct all the observations.