Shadow of a Ghost (1981)

An old mansion, sealed for years, re-opens as a museum. A ghost is sighted by the museum's guide, our heroine, who has fallen for a social outcast, a scientist obsessed with finding ghosts with his machines. A film with a ghost, but a lot more than just a ghost story. A film about embracing the advancement of society, opening one's mind and pursuing one's beliefs against all odds. Based on a scifi novel.