A lot of photography is all about what’s in focus and what isn’t.  While a casual photographer may get upset that not everything in the picture is in focus, an artist and professional will use that fact to their advantage.

In photography it is important to understand that the distance between the subject and the lens is critical.  A lens doesn’t care what the subject is or how it’s composed; all it cares about is how far away it is.  When the lens is focused to that distance then anything at that distance will be focused.  That doesn’t mean to say, however, that nothing else will be focused.

To examine that idea closer we’ll have to understand the different fields of view.  Most scenes can be easily broken up into a foreground, middle ground and background.  The foreground is comprised of the subjects closer to the camera with the background being those things that are farthest away.  If the photographer were to focus on something in the middle ground, it is possible that things in the background and foreground will still be clear.

The measure of how much distance is actually in focus is called depth of field.  The wide depth of field occurs when the focus covers a large distance while a narrow depth of field is when the focus is at a very specific distance.

When taking a picture of a flower for example a photographer may choose to create a narrow depth of field.  This will result in the flower showing up crisp and sharp but everything behind it is a blur. 

When taking a shot of a landscape a wider depth of field is often preferred.  This will result in a photo where the trees in the rocks in the foreground, for instance, are in focus as well as the trees in the background and everything in between. 

The depth of field can be controlled by adjusting the camera’s aperture settings, or “F-stop.”  The higher the F-stop is, the smaller the aperture gets.  The smaller the aperture is, the more depth of field the photo gets. 

This can be a tricky thing but is worth paying attention to even when a camera is set on automatic.  If a camera’s automated system decides to use a small F-stop but you were hoping to have a lot of things in focus then it’s time to override the camera’s settings.  All of a sudden that manual feature looks appealing. 

The depth of field often haunts people who are just learning how to use their camera’s manual settings.  In a brightly lit setting it can be tempting to use an ultra quick shutter speed.  The problems is that that results in having to use a low F-stop.  Now there is a very shallow depth of field being created.  It is possible in these cases to wind up with a picture with such a shallow depth of field that someone’s nose is in focus but the rest of their face is not.

Get used to being aware of the possible depths of field and your pictures will soon benefit.