Now the same procedure with a sphere, but without relativistic effects. You see the sphere distortet to some kind of disk: this is because of the limited speed of light. Light rays need a certain time to reach your camera - light from more distant point needs a longer time than light from a point near you. The image in your camera is created by the light rays that reach you simultanously. So the ray from the distant point has to start before the ray from the near point. (mpeg 200 frames, 1.1 MB)