Depth Of Field
Depth of Field is the area in an image that appears sharp and in focus. In an image with a shallow depth of field, the subject is in focus while the background is blurry. With an increased depth of field the background is also in focus. Our vision is better in the daytime is because our pupils constrict in the light, giving the lens of our eyes a larger depth of field, allowing us to see far-away objects more clearly.