So, What Does Aperture Do For Me?

Have you noticed that you can see further distances clearly during the day than you can at night?

The reason is, in dark conditions your vision isn’t as clear as it is during the day and that reason is aperture.

During the day, especially in bright conditions, your pupil gets really small giving you, effectively a small aperture.

With a small aperture more of the scene in front of you is in focus. While at night your eye has to open up wide in order to let more light inside your eye.

With your pupil open wide you can’t see as far or have as much of a scene in focus. This concept is known as Depth of Field .

As the aperture in your eye, and subsequently in your camera, gets smaller so does the depth of field.

This means that with a really small aperture more of your scene is in focus which mean more of it front to back is in focus.

For instance, have you ever seen wildlife photography with a blurry background? That was taken with a wide aperture which has a very shallow depth of field,

On the other hand landscape photography, where much of the scene even far away from the focal point, is still in focus. This type of photography is usually taken with a small aperture which gives a larger depth of field.
Flowers, Lakes, Peaks
from: "20 Lakes Basin, Hoover Wilderness" By Stephen PaulThis photo was taken with a small aperture. Notice that the distance is in focus and also the items in the foreground are in focus as well.