There are a lot of myths about photography that bug me that people perpetuate. Not every weird looking photo from the 19th century is a Memento Mori (i.e. post-mortem). A lot of photos floating around on the internet labelled as such are actually living subjects. And only in the earliest days did photographs take a long time to produce. By the Civil War exposure times were rapidly becoming comparable to modern cameras.People didn't smile for photos because they thought it made them look foolish. Portraits were supposed to be serious and formal.