Understanding the Exposure Triangle in Photography: A Beginner’s Guide

Morning folks, I trust you had a good week so far. If you’ve been dabbling in photography, you’ve probably heard about the exposure triangle. It’s a fundamental concept that every photographer should understand. Don’t worry, we’re going to break it down in a simple, easy-to-understand way. I’ve always explained this concept in my personal photography workshops or lectures, but it would be good to share it here too.

If you’re interested in personal coaching or 1-on-1 mentoring, get in touch with me.

What is the Exposure Triangle?

The exposure triangle is a concept that illustrates the relationship between three fundamental elements of photography: aperture, shutter speed, and ISO. These three elements work together to control the amount of light that reaches your camera’s sensor and determines how light or dark your image will be.

There are pros and cons to adjusting each of these elements and I’ll explain further which are the ones I personally would change first, before the others.

The Three Elements of the Exposure Triangle

1. Aperture

Aperture refers to the size of the opening in your lens. When you adjust your aperture, you’re changing the size of this opening. A larger aperture (represented by a smaller f-number) lets in more light, while a smaller aperture (represented by a larger f-number) lets in less light.

A digital camera is literally based on how our own eyes work. Think of aperture as your eyes iris (black part). It will open and close to let in more/less light as needed. The camera aperture operates in exactly the same way.

But aperture does more than just control light. It also affects depth of field, which is the amount of your image that’s in sharp focus. A larger aperture creates a shallow depth of field (blurry background), while a smaller aperture creates a greater depth of field (more of the image in focus).

The image below illustrates this visually:

2. Shutter Speed

Shutter speed is the length of time your camera’s shutter is open. A faster shutter speed (represented by a smaller fraction of a second) lets in less light and freezes motion, while a slower shutter speed (represented by a larger fraction of a second or even several seconds) lets in more light and shows motion blur.

Again, the eye analogy is likened to blinking fast or slowly. Most shutter speeds on cameras are in the really high end of fractional seconds. You’ll start learning what shutter speeds are suitable to different environments as you experiment in different situations, or at least a general idea of where your shutter speed should be.

3. ISO

ISO is a measure of your camera’s sensitivity to light. A lower ISO (e.g., 100 or 200) means less sensitivity, while a higher ISO (e.g., 800 or 1600) means more sensitivity (but an increase in digital noise).

The eye is a perfect example again, because remember what its like walking out a dark room into the bright daylight? That is what your sensor is experiencing if your ISO is too high. Out of the 3 pillars of these fundamentals, ISO is the one I change LAST if I need to adjust my settings manually. I’ll try make adjustments on aperture and shutter speed first.

Balancing the Exposure Triangle

Now that you understand the three elements of the exposure triangle, the challenge is to balance them. This is where the concept of “stops” comes in. In photography, a stop is a measure of exposure. If you increase your exposure by one stop, you’re doubling the amount of light. If you decrease it by one stop, you’re halving the amount of light.

Here’s how it works in practice:

• If you want to use a larger aperture to get a blurry background, but your image is too bright, you could use a faster shutter speed or a lower ISO to compensate.
• If you want to use a slower shutter speed to show motion blur, but your image is too dark, you could use a larger aperture or a higher ISO to compensate.

The key is to experiment with different settings and see how they affect your image. With practice, you’ll get a feel for how to balance the exposure triangle to get the results you want.

FAQs

What are the 3 important parts of the exposure triangle?

The three important parts of the exposure triangle are aperture, shutter speed, and ISO. These three elements work together to control the amount of light that reaches your camera’s sensor and determines how light or dark your image will be.

Why is it important to understand the exposure triangle for photography?

Understanding the exposure triangle is crucial for controlling how your images look. It allows you to manipulate light, depth of field, and motion to create the desired effect.

Is ISO 800 brighter or darker than ISO 200?

ISO 800 is brighter than ISO 200. A higher ISO number means more sensitivity to light, which results in a brighter image. However, a higher ISO also results in more noise or grain in your image.

How do you explain exposure in photography?

Exposure in photography refers to the amount of light that reaches your camera’s sensor. It’s determined by three elements: aperture (how big the opening of the lens is), shutter speed (how long the sensor is exposed to light), and ISO (how sensitive the sensor is to light). These three elements make up the exposure triangle.

Understanding the exposure triangle is a fundamental part of photography. It might seem a bit complicated at first, but with practice, you’ll be able to manipulate aperture, shutter speed, and ISO to create exactly what you want and have full control.

Written by Seagram Pearce