Triangle of Exposure

The exposure triangle in photography is the relationship between aperture, shutter speed, and ISO. These three settings work together to control how much light reaches the camera sensor and therefore how bright or dark the photo becomes.

The three parts

• Aperture controls the size of the lens opening, which affects both brightness and depth of field.
• Shutter speed controls how long the sensor is exposed to light, which affects brightness and motion blur.
• ISO controls sensor sensitivity to light, which helps in darker scenes but can add noise.

How it works

If you change one setting, you usually need to adjust at least one of the others to keep the same exposure. For example, using a faster shutter speed lets in less light, so you may need a wider aperture or a higher ISO to compensate.

Simple example

If you want to freeze fast action, you might use a fast shutter speed. That reduces light, so you could open the aperture wider or raise ISO to keep the image properly exposed.

In short, the exposure triangle is the basic balance system that helps you control both exposure and creative effects in a photo.