In this image, I created a "ghosting" effect straight out of the camera. You simply set a slow shutter speed, let your subject move slightly, then fire the flash to freeze your subject at the end of the movement.
Here's where previsualization comes into play. I knew I wanted to "ghost" this image, but I did not want it in color. I wanted it to look like an old black and white "ghost hunter" image. So, the only post production I did was increase contrast and convert the image to black and white.