Using Maximum Depth Of Field
A wide-angle lens with a small aperture keeps everything in the foreground and background in focus.
A typical infinity focus icon. A few cameras
have an infinity focus mode that takes advantage of hyperfocal distance.
Often you will want to get as much depth of field as possible because important parts of a scene that you want sharp are both near to and far from the camera. Maximum depth of field seems particularly important for photographs of landscapes and other scenes where a distant horizon is a part of the picture.
When a subject extends to the far distance, many photographers unthinkingly focus on that part of the scene. When you are focused on that distant point everything from that point and beyond will be sharp. But since one-third of the available depth of field falls in front of the point on which you are focused and two-thirds behind it, you are wasting two-thirds of your depth of field because
everything past the focus point is going to be sharp anyway. That may mean that some other part of the scene in the foreground will not be included in the one-third remaining depth of field and consequently will not be sharp.
Instead of focusing on infinity, if you focus on some object one-third of the way between you and the horizon, you will have brought forward the point on which you are focused and so increased the depth of field in the foreground of your picture. This new point of focus is called the hyperfocal distance. You can use this procedure not just for landscapes, but whenever you want to shift depth of field toward and away from the camera.
When you focus on the most distant part of the scene (top), here it's the mountains, all available depth of field to the right of that point is wasted.As a result, the middle and foreground are not sharp because they don't fall within the range of available depth of field.
By focusing on the hyperfocal distance (bottom), the most distant part of the scene remains in focus but the near point of depth of field moves closer to the camera. The entire scene is sharp.
HOW TO: INCREASING DEPTH OF FIELD
. Photograph in bright sun so the aperture closes down.
. Zoom the lens out to a wider angle of view or move farther away from the subject.
. Switch to aperture priority mode and select a small aperture such as f/11 or switch to landscape or infinity focus mode.