The element that connects Shutter Speed, Aperture and ISO into one is the exposure triangle. Understanding the exposure triangle correctly, it means you can get to grips with exposure as a whole. 

The Exposure Triangle - A Beginners Guide

In this guide, we explore the exposure triangle in-depth, look at how best to use the exposure triangle and some awesome examples. 

What is The Exposure Triangle?

The exposure triangle in photography is essentially how much light reaches your sensor. It’s also known as the “Exposure Value”. The Exposure Triangle in Photography. The exposure triangle is made up of three parts – Shutter Speed, Aperture and ISO

The Exposure Triangle
The Exposure Triangle

The exposure triangle is incredibly important both in photography and filmmaking. These three need to be working in unison and if one changes, the other two must as well. 

It’s unity. The exposure triangle helps you create better imagery. We delve into the detail on how best to utilise the exposure triangle. But before we dive into that, let’s explore each part in a bit more detail: 

Shutter Speed

Shutter speed is essentially how long the shutter stays open on your camera measured in milliseconds. If your shutter speed isn’t open long enough or open too long you’ll have an over or under-exposed image. 

However, by timing the shutter speed correctly, and balancing it with the aperture and ISO you can create, crisp, iconic images. Slowing your shutter speed also allows you to create a cool motion blur. 

The smaller the number the faster the shutter speed.

Aperture

The aperture is the lens opening in the camera which allows the light to pass through. Setting a large aperture essentially let’s more light in, and a lower aperture will let less light in.

Aperture is defined by “f/stops’ and they are displayed as follows: 

  • ƒ/1.4
  • ƒ/2
  • ƒ/2.8
  • ƒ/4
  • ƒ/5.6
  • ƒ/8
  • ƒ/11
  • ƒ/16

The lower the aperture number, the more light is let in. For example, 2 will let in more light than 11.

ISO

ISO is essentially how sensitive your camera is to light. The ISO is expressed as a number, for example, ISO 100. 

ISO stands for the International Organization of Standardization which establishes sensitivity ratings for camera sensors. 

For instance, the higher the ISO number the more sensitive the camera is to light. It’s useful for nighttime photography but used in daylight for example will cause a lot of noise within the shot.

Therefore a lower ISO number is preferred to prevent overexposure.

How Do These Three Complement Each Other?

All three of these aspects work with one another to achieve the right exposure for your images and video footage

AN example of this is if you open up the aperture longer to let more light in – you must compensate with a low ISO or faster shutter speed to balance it out.

How Does The Exposure Triangle Work?

The exposure triangle as mentioned above is the balance of the three elements, shutter speed, ISO and aperture. All three must balance correctly to get the right effect, whether it’s looking for motion blur, or a sharp, crisp image – the three factors must balance. 

Examples of How to Use the Exposure Triangle

There are plenty of ways to use the exposure triangle, and we explore these methods down below. 

Depth of Field

Depth of field is a great example of utilizing the exposure triangle to the max. The depth of field effect is where you control the focus area of the image to give it depth. 

Photographers and filmmakers tend to shoot with a small aperture to achieve large depths of field. Whereas a large aperture achieves a shallow depth of field. The Bokeh Effect is the perfect example when utilising the shallow depth of field. 

Read our in-depth guide on the Bokeh Effect here.

Motion Blur

Motion blur is one of the best effects to come from the exposure triangle. Creating motion blur starts with the camera’s shutter speed. For instance, slowing the shutter speed allows you to create motion blur

Depending on your camera’s setup you can either manually balance the ISO and aperture with the shutter speed. Or, you can use the shutter priority mode. This essentially balances the ISO and aperture automatically to allow you to create the motion blur.

Remember: 

  • A decrease of one-stop in shutter speed is equal to double the length of time the shutter is open. 
  • A 50 percent decrease in the size of the shutter opening is equal to one-stop decrease in aperture. 

Dark Shots

When shooting throughout the night or in the dark it’s best to shoot using manual. You will need to ensure you set your aperture much lower than in normal light. ISO should be reduced to as low as possible to counter. 

Then set the shutter speed to be shorter to capture a crisp image. 

We hope this article on the exposure triangle was useful for you! Check the rest of our photography and filmmaking articles below. 

Happy filmmaking!