Pentax K100D User Manual - Page 137

135 Effect of Aperture Adjust the amount of light hitting the CCD by changing the aperture. Opening the aperture (reduce the aperture value) Objects closer and farther than the focused subject will be more out of focus. For instance, if you take a picture of a flower against a landscape with the aperture open, the landscape in front and behind the flower will be blurred, emphasizing only the flower. Closing the aperture (increase the aperture value) The range in focus expands forward and backward. For instance, if you take a picture of a flower against a landscape with the aperture narrowed, the landscape in front and behind the flower will be in focus. 5 Function Reference Depth of Field When you focus on a portion of the subject, there is a range in which object closer and farther will also be in focus. This focused range is called the depth of field. • The depth of field for the q differs depending on the lens but compared to a 35 mm camera, the value is roughly one aperture setting lower (the focused range becomes narrower). • The wider the wide-angle lens, and the farther away the subject, the deeper the depth of field is (some zoom lenses do not have a scale for depth of field because of their structure). Depth of field Shallow Area of focus Narrow Aperture Open (Smaller value) Lens focal length Longer (Telephoto) Distance to the subject Near Deep Wide Close (Larger value) Shorter (Wide-angle) Far