How to master ISO, aperture size, and shutter speed

Exposure is determined by ISO, aperture size and shutter speed. Learn how to use your camera's manual settings to capture the best images.

With modern digital cameras, you can use sophisticated automatic modes in different situations. Although auto-mode is a great place to start, learning how to adjust exposure yourself will give you greater creative control.

If you’re not ready to switch to full manual mode, many newer cameras feature aperture priority and shutter priority modes. With these semi-automatic modes, you can control either the aperture or shutter manually while the camera automatically adjusts the other.

ISO settings

ISO stands for International Standards Organization and originally described the ability of a film to gather light. In digital photography, ISO refers to the signal gain of the camera's sensor, or how sensitive it is to light. If your shot requires a shallow depth of field, large aperture and a fast shutter speed, you may need to adjust the ISO setting to suit.

Aperture size

As with the pupil in a human eye, a camera's aperture controls how much light passes through. A large aperture lets in more light and reduces depth of field – the range in which objects will be in focus. In contrast, a smaller aperture creates a large depth of field, keeping more of your shot in sharp focus.

Shutter speed

To avoid blurry pictures, you need to match your camera's shutter speed to your subject's speed. Sports photography, for example, typically uses a high shutter speed – 1/500 or higher. If you use a slower shutter speed than your subject, you’ll also capture some blur which can be great for adding a sense of motion.

Ready to master your camera? Learn more photo editing tips and tricks. When you’re ready to edit, try Lightroom to perfect your shots and bring your creative vision to life.