Popular Science: Everyone knows light exposes film, but other forms of radiation do as well—a fact you can use to take pictures in some pretty unusual ways.It’s also how radioactivity was first discovered. In 1896, French physicist Henri Becquerel stored some x-ray film in a drawer along with a uranium rock which, he found after developing the film, had exposed the film.It’s not hard to repeat Becquerel’s experience at home with standard film. Theodore Gray at Popular Scienceexplains how with Fujifilm ISO 3000 instant film.