The immediate impetus for recording dynamic sights was a dispute over whether all four feet of a galloping horse were off the ground at the same time. The developers of the early recorders and playback devices attempted to create machines that replicated sounds and sights as precisely as possible. Religious and state authorities have paid little attention to audio recordings, but as the motion picture industry matured, some attempted to control their distribution. The most common use of recordings is to provide entertainment. Many governmental agencies, religious groups, and commercial companies began to produce and distribute documentaries in the 1930s to advocate special interests. Recording technologies allow sociological researchers to make more refined analyses of social phenomena than previously possible. Most people most of the time distinguish experiences derived from recordings from the experiences derived from the mundane world without great difficulty. The only other information technologies that approach recordings in fidelity are still photography and live broadcasting.