In addition to ghosts and poltergeists, Grosse also investigated numerous claims of precognition. He also put together an extensive collection of alleged examples of psychic photography. He continued this work right up until the summer of 2006.
Grosse examined not only ghosts and poltergeists but also numerous reports of precognition. He compiled an extensive collection of alleged psychic photographs. This research was conducted up to the summer of 2006.