The exposure triangle is simply the relationship between your ISO, shutter speed and aperture. These three components work together to create an actual exposure or photograph.
ISO is a term from the film photography days which referred to film sensitivity to light.
The lower the film sensitivity or ISO the less “grainy” the photo will be. The lower the ISO, the cleaner the photo is. Shutter speed is simply the amount of time (measured in seconds) that the camera’s shutter is open allowing light to hit the sensor to make an exposure. The higher the number, the fast the shutter will open and close. Aperture refers to how large or small the opening is through the lens. This opening is what controls how much or little light can pass through the lens and onto the camera’s sensor. It is also known as the F-stop.
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