Beginner’s Guide to Aperture
What in the world is aperture?
Aperture refers to the size of the opening in the lens through which light enters your camera. When you take a picture, you can specifically choose the size of this opening by adjusting the f-stop. When you change your f-stop, you change the size of the opening. Doing so results in two main things: 1) it changes the light entering your camera and 2) it affects the depth of field. Take a look at the illustration below:
This illustration represents the lens opening. You can see how as the numbers get bigger, the opening becomes smaller.
How Aperture Affects Light
Wider apertures (small f-stops) allow more light to enter the camera. So if you take a photo and it’s too dark, one of your options is to choose a smaller f-stop to brighten it.
Narrow apertures (large f-stops) allow less light to enter the camera. So if you take a photo and it’s too bright, you can choose a larger f-stop to darken it.
f/2 | 1/60th | ISO 400
f/4 | 1/60th | ISO 400
f/8 | 1/60th | ISO 400
How Aperture Affects Depth of Field
Wider apertures (small f-stops) create a shallow depth of field. This means that only a small portion of the image is in focus while the remainder of it is blurry. Shallow depth of field is good for isolating a subject, focusing on details, or shooting portraits.
Narrow apertures (large f-stops) create a deep depth of field. This means that more of the image will be in focus. Deep depth of field is good for landscape photography.