You asked about pictures of unsmiling faces. I don't think the idea of "smile for the camera" was in, then. Remember, when picture taking first started, the cameraman held a stick up with the flash at the top, above his head. When the flash went off it was really startling. I think people had to brace themselves psychologically for the flash and weren't thinking about smiling. And the whole process of picture taking may have been an ordeal. Peggy Guinn Bowen