The Canon EF 600mm f/4 L IS II USM Lens has the great capability of making the background into a smooth blur of color. The smooth blur of color in this example is a pasture being lit by a nearly-set sun.
The rusty barbed wire and old post are placed into the frame using the rule of thirds. I can't say that I was thinking about the rule of thirds when I took this picture, but that is apparently what worked for my eye in the viewfinder.
Camera and Lens Settings
600mm f/4.0 1/125s
5760 x 3840px