The initial Corona missions suffered from mysterious border fogging and bright streaks which appeared irregularly on the returned film. Eventually, a team of scientists and engineers from the project and from academia (among them Luis Alvarez, Sidney Beldner, Malvin Ruderman, Arthur Glines, and Sidney Drell) determined that electrostatic discharges (called corona discharges) caused by some of the components of the cameras were exposing the film. Corrective measures included better grounding of the components, improved film rollers that did not generate static electricity, improved temperature controls, and a cleaner internal environment. Although improvements were made to reduce the corona, the final solution was to load the film canisters with a full load of film and then feed the unexposed film through the camera onto the take-up reel with no exposure. This unexposed film was then processed and inspected for corona. If none was found or the corona observed was within acceptable levels, the canisters were certified for use and loaded with fresh film for a launch mission.