Isolation, space and tension.
Simplicity is power when creating graphic images.
Isolating the subject from the background is the perfect way to create an unadulterated focal point.
In this image the contrast between the black background and the white subject cleanly define the edges of the horse and rider. By converting the image to black and white and boosting the overall contrast the sense of drama is also heightened.
Lastly the elimination of distracting background clutter compliments the tension of the subjects suspension in space.
"Masters" Spruce Meadows, Calgary Alberta. Nikon D300s, Nikkor 300mm f/8@1/2000 sec, 400 ISO.
From Photographers Journal