[Obscura]

Depth of Field

There are a number of results of changing the aperture of your shots that you’ll want to keep in mind as you consider your setting but the most noticeable one will be the depth of field that your shot will have.

Depth of Field (DOF) is that amount of your shot that will be in focus. Large depth of field means that most of your image will be in focus whether it’s close to your camera or far away (like the picture to the left where both the foreground and background are largely in focus – taken with an aperture of f/22).

Small (or shallow) depth of field means that only part of the image will be in focus and the rest will be fuzzy (like in the flower on the right. You’ll see in it that the tip of the yellow stems are in focus but even though they are only 1cm or so behind them that the petals are out of focus. This is a very shallow depth of field and was taken with an aperture of f/4.5.

Aperture has a big impact upon depth of field. Large aperture (remember it’s a smaller number) will decrease depth of field while small aperture (larger numbers) will give you larger depth of field.

It can be a little confusing at first but a good way to remember it is that small numbers mean small DOF and large numbers mean large DOF.

The best way to get your head around aperture is to get your camera out and do some experimenting. Go outside and find a spot where you’ve got items close to you as well as far away and take a series of shots with different aperture settings from the smallest setting to the largest. You’ll quickly see the impact that it can have and the usefulness of being able to control aperture.