This shot was made with the camera mounted on the roof of a car driving across the Golden Gate Bridge. The tower fans out along the top of the box as the car approaches it. Notice the scanning at different relative speeds on the sides of the box. On the right side (top panel) the cars to the right of the camera car are passing at nearly the same speed, so they have time to scan with some length to them. The cars on the left side (third panel down) are passing somewhere near a relative speed of 100 mph, so they appear as short blips.