Aperture in photography is often the subject of some confusion, leaving people feeling stuck using their cameras in auto mode without ever diverting into other modes.
Taking photographs in manual mode (if your camera has it) will allow you more control over the image, including depth of field.
What Is Aperture In Photography?
Aperture is the measurement of the opening where the light and image comes in to the lens on your camera. This is often adjustable and measured in “f-stops”, that describe how open of closed the diaphragm is. The larger the aperture, the more light is able to be captured. As you move through the f-stops, each one either doubles or halves the amount of light captured by your camera, depending on the direction you choose. The larger the number, such as f/8, means a smaller entrance point while a smaller number, such as f/2.8, means a larger opening.
The human eye has an aperture of about 4mm, expanding to 8mm (f/2.1) in the dark and reducing to 2mm (f/8.3) in brightly lit areas. The iris is the diaphragm that automatically adjusts the aperture of the eye depending on the amount of light that is present.
What Does Aperture Do?
Aperture in photography is used to limit the amount of light entering the lens. A smaller f-stop will let in more light than a larger number one. Aperture also effects Depth of Fieldw (DOF).
Each time you change your aperture, you also change your depth of field. The larger f/number of the aperture, the smaller the depth of field. This is important when you want your subject in focus and the background blurry, such as when taking portrait shots. Macro photography often heavily uses aperture to ensure that the image is sharp where the photographer wants it to be, and blurry elsewhere.
How Do I Use Aperture?
In auto mode – if your camera has one – the aperture is selected for you based upon the conditions in which you are taking the photo.
If you are in a low light situation:
- Adjust the aperture to make the entrance aperture larger will allow more light to be in the image.
- Use care while adjusting the aperture, as a large aperture allows for more distortion and other optical aberrations.
- Read the manual that came with your camera to learn how to change the aperture, as each camera is different.
- Check your lens to see what your minimum and maximum aperture is.
One of the best ways to learn how to use different aperture settings is to take your camera, find something you’d like to take a picture of at varying distances and experiment with changing the aperture.
You’ll see how different apertures affect the image!
- Check your manual on how to manually change aperture.
- Aperture changes the depth of field.
- The larger the f/number, the smaller the aperture.
- The smaller the f/number, the larger the aperture.
- Larger apertures can cause distortion and other optical aberrations.