"Smile for the Dead" uncovers the eerie mystery of William H. Mumler's spirit photography and his ghostly portraits of the1800s. This documentary investiga 　　"Smile for the Dead" uncovers the eerie mystery of William H. Mumler's spirit photography and his ghostly portraits of the1800s. This documentary investigates Mumler's techniques and why society so needed him in the post-Civil War era. 详情