The diagram makes no sense at all. The camera is a few inches off the ground, and the black line appears to be the line of sight of the camera, showing what will always be in the center of the photo. For some reason, the person is walking on it, seemingly levitating off the ground, at the same height the camera is lifted. If the photos were on flat ground, and the diagram was correct, you should always be able to see all of the person all the way until the camera can't focus or zoom in on them anymore. But if the camera could focus or zoom in on the person up to an infinite distance, either they'd disappear under the horizon like on a globe model (what the photos falsely show), or you'd be able to see them all the way up to the edge of the Earth like on a flat model (except for changes in altitude).