Depth of field is the term used to describe the zone in which photographic subjects will be in focus. Anything in front of or behind that zone will be out of focus. You can have a very narrow depth of field to focus on a very specific point on a subject, like this:
Or you can have a very wide depth of field to get almost the entire image in focus, like this:
Most cameras these are digital, and most digital cameras are of the “point and shoot” variety. This means that they have what’s called an “infinite depth of field”, which basically means there is no aperture adjustment in the camera. That usually means that something that looks great in real life will often look flat and uninteresting as a photo.
Even though I’ve had a change of heart about camera phones recently, the fact remains I can’t escape just how great my old Canon 10D SLR really is. The ability for me to adjust the aperture on this camera to change the depth of field makes all the difference. Even in “auto” mode, this camera does a great job of making the subject snap to life. This was just a quick “point and shoot” shot taken of the Auggie the doggie (or as I call him, Doogins):
As a thumbnail it’s hard to notice the subtle difference depth of field makes, but click on the image to bring it up to full size and you’ll see what I mean. The photo below is from the local street fair going on today. Again you can see the difference depth of field makes to make the subject really jump out from the surrounding elements.
Of course, depth of field can also work against you if you are set to autofocus and the camera decides to focus on the wrong subject:
These images have nothing to do with depth of field, just interesting things I came across at the street fair.