What Happened to Selenium Photocells? The Sensor That Let Light Meters Work Without Batteries

#SeleniumPhotocells #VintageTechnology #CameraHistory What happened to selenium photocells, the remarkable sensors that allowed light meters to work without batteries? For decades, selenium photocells quietly powered exposure meters using nothing more than the light they were designed to measure. From the first practical selenium light meters of the 1930s to their golden age in mid-century cameras, these self-powered sensors became one of photography’s most elegant technologies. Their distinctive honeycomb cells appeared on countless cameras and handheld exposure meters, giving photographers reliable readings without switches, batteries, or external power. But beginning in the 1960s, cadmium sulfide sensors offered greater low-light sensitivity and much smaller dimensions. As through-the-lens metering became increasingly important, selenium photocells could no longer fit the direction camera design was taking. By the 1980s, silicon photodiodes had pushed light-meter technology even further, and selenium gradually disappeared from new cameras. In this video, we explore how selenium photocells worked, why photographers trusted them for decades, what technologies replaced them, and why some vintage selenium light meters are still functioning today. If you enjoy documentaries about forgotten electronics, vanished technologies, vintage components, and the inventions that once shaped everyday life, subscribe to the channel for more stories like this. #LightMeters #FilmPhotography #PhotographyHistory #AnalogCameras #TechHistory