The Crow

I went out and took some pictures today. I snapped this and was really happy with how it came out. I've been playing around with my aperture, and still really don't understand what I'm doing. Every picture I took , I took with a high aperture and a low aperture, and somewhere in the middle. Except this bird. He was just flying by, I have no clue what my aperture was set at, and discovered this when I got home. I've got about four shots of him in various forms of flight and they all came out like this.