My definition of depth of field is the range of distance from the camera that is the sharpest to be in focus. Then its broken down into to parts, Shallow depth of field and extensive depth of field. Shallow depth of feild is your subject is in focus but the rest of the picture is blurred and extensive depth of field is when your whole image is in focus.To get shallow depth of field i put the Af Area to 1 point and that point was on my subject. then put my aperture to F3.5 but if you can go lower you would get a better result. After that i set my shutter to about 1/200 with a iso of 100. In rode to get the extensive depth of field you want everything in focus so i put the aperture to the my highest F22 an because i took the picture while moving the shutter speed had to be higher about 1/400. I prefer shallow depth of field its easier for the viewer to look at. your eye is drawn to 1 subject as appose to extensive depth of field.