When I started photography, there was a lot that was lacking. I am a self-taught photographer, therefore, had no guidance whatsoever while learning. I knew that at some point I wanted to earn a living from photography but really had no idea whom to apprentice under. Instead of sitting around and waiting for someone to teach me the craft, I bought my own camera and began practising as much as I could. I studied as much as I could form online educational platforms and books.

This process of teaching myself is something that I appreciate so much because it built a passion for photography that will never go away. I failed at achieving what I would envision so many times but kept at it until I figured out how to create what I imagined. The downside to teaching myself was that it took a very long time to understand some basic concepts. The Exposure Triangle was something that took me three years to understand.

I was forced to understand the concept when I started using artificial lighting in my images. Once I understood the concept behind the exposure triangle, most of what I had struggled with began to fizzle away. I began to look at photography with new eyes. I gradually became more focused on composition and storytelling. The exposure triangle is a concept that pieces everything together in photography.

For a long time, I believed in using specific settings for specific scenarios. I stuck to this method for a long time. However, when it came to using artificial lighting this method failed severely. I had to go back and relearn the process. In today’s blog post I will try to demystify what the Exposure Triangle is. Understanding it at the very beginning of your journey will save you a lot of time and headaches. If you have already started and you did not have an understanding of what the exposure triangle was, then today is your lucky day.

What is the Exposure Triangle?

The exposure triangle is the relationship between the exposure settings. Exposure settings are Aperture, Shutter Speed and ISO. To know more about these read this article. The relationship between these three exposure settings is called the exposure triangle because when one exposure setting is adjusted, another exposure setting has to be adjusted as well to bring an image back to an ideal exposure. Hence the relationship is visually represented as a triangle.

Now before I go too far, there is the need to introduce another term that really throws people off.

A Stop of Light

There are so many definitions of a stop of light. It’s so complicated it hurts. You do not need to know all the complex definitions and stuff. Think about it this way. A stop of light is a unit measurement of the amount of light in a scene. A stop of light is similar to measuring length for example in metres. The beauty about this whole concept is that as a photographer you do not need to know how many stops of light there are in a scene because it just does not matter. There are more important things like composition.

However, as a photographer, you first need to know how stops and the exposure triangle relate and secondly, know how to determine the number of stops you need to move amongst the exposure settings.

Switching Between Stops

If there is information that I am going to give you today that might change everything for you as far as exposure settings and how they relate to the exposure triangle is this.

Every click that you make on your camera for any exposure setting is 1/3 of a stop.

Once you have this you are home free with the exposure triangle. Every click that you make to adjust any exposure setting on your camera is 1/3 of a stop. Therefore to move a full stop of light you need to make 3 clicks.

Example (try do this practically on your camera)

Aperture; Keeping the shutter speed and ISO constant. Change this exposure setting by a full stop.

f/8: 1/200: 100 –  f/11: 1/200: 100

Shutter Speed: Keeping the aperture and ISO constant. Change this exposure setting by a full stop.

f/8 : 1/200: 100 –  f/8 : 1/400:100

ISO: Keeping the shutter speed and aperture constant. Change this exposure setting by a full stop.

f/8: 1/200: 100 – f/8: 1/200: 200

Using Stops to Adjust Exposure

From the example above, we have adjusted each of the exposure settings by a full stop. We adjusted one exposure setting without affecting the other two in each of the three scenarios.

In a real-world situation, this will not always be the case. Adjusting one exposure setting will always affect the amount of light entering the camera. This means that by adjusting one exposure setting we will either increase the amount of light or decrease the amount of light. In order to adjust for an increase or decrease in light, we need to adjust another exposure setting to compensate for the loss or gain of light in order to get to our ‘correct’ exposure.

This is quite a lot to take in so let me use an example to better illustrate what I mean.

This is a scene within one of the rooms where I live. There are two large windows letting in quite a bit of natural light into the scene. Off the top of my head, I am going to randomly pick some exposure values to take images of my toy dinosaur Brutus who is happily posing on the table.

BTS: Shoot Location
BTS: Camera set and ready for action
BTS: Brutus in all his glory

For the aperture, I will use f/5.6. For the shutter speed, I will use 1/200 and an  ISO of 100.

This is an image of the resulting image taken in this scene.

Exposure Settings: f/5.6 1/200 ISO 100

The resulting image from this scene is completely dark. There are no details of Brutus or the table. This is clearly not an ideal exposure and we, therefore, need to adjust the exposure settings accordingly in order to get some details.

In order to do this, I will need to have an understanding of why my settings did not capture the right exposure and also have an understanding of light in the scene. Notice that there are two large windows. This means that there is a lot of natural light coming into this scene. Based on the exposure settings that I chose, it means that they were not appropriate to capture the light entering this scene. The aperture size (f/5.6) was small. This means that the amount of light entering the camera was not much. The shutter speed (200th of a second) was also a bit too high meaning that it also cut out the little light let in by the small aperture. The ISO (100) is the lowest ISO setting on my camera meaning that it was also not as sensitive to the little light entering the camera. This resulted in a dark image.

We did not enter the correct exposure values into our camera for this scene. The question now is how do we adjust these settings to achieve the correct exposure. This is where the Exposure Triangle comes in. It is clear that f/5.6, 1/200, ISO 100 are not appropriate exposure values for this scene. We also know that by observing the scene we are shooting in, there is a lot of light and Brutus deserves a better photograph with all that light. Our exposure settings need to be adjusted to let in more light into the camera. The first setting I will adjust is the Shutter speed. In this article, we identified that the shutter speed controls the amount of light and motion in an image. I have placed the camera on a tripod and Brutus is not moving. I can, therefore, let in more light into the camera by slowing down the shutter speed. I want to slow down the shutter speed by 2-stops of light(randomly chosen). In order to do so, I will adjust using a scroll wheel on my camera. (Remember 3 clicks is 1 full stop of light)

{1/200 – 1/160 – 1/125 – 1/100} {1/80  –  1/60  –  1/50 }

            One-Stop of Light                  Two Stops of Light

I will, therefore, lower the shutter speed from 1/200 to 1/50 and take a photo without first affecting the other exposure settings. The final exposure is as below.

Exposure Settings: f5.6 1/50 ISO 100

After reducing the shutter speed by 2-stops of light

The resulting image shows some details of the background and some details on Brutus’s body. We have let in a little more light but still not enough to show all the details that we want to see in our shot. This means that we have to still let in more light. To do so we can open our aperture much wider, as f/5.6 is rather small. Let us try to bring in 2-stops of light as well using the aperture by widening it. To do so I will use the same scroll dial on my camera to adjust the aperture. (Remember 3 clicks is 1 full stop of light).

{f/5.6 – f/5.0 – f/4.5 – f/4.0} {f/3.5  –  f/3.2  –  f/2.8 }

One-Stop of Light             Two Stops of Light

I will, therefore, open up the aperture from f/5.6 to f/2.8 and take a photo without first adjusting the other exposure settings. The final exposure is as below.

Exposure Settings: f2.8 1/50 ISO 100

Image after increasing the aperture by 2-stops of light

I can see Brutus!!!! We have been able to come up with an ideal exposure for this scene. Our ideal exposure is now f/2.8 1/50 ISO 100.

This is a side by side comparison of what we started with and what we finally came up with.

I know you might be asking yourself why I did not adjust the ISO. In this article, we talked about the effects of increasing the ISO on an image. The first reason I did not adjust my ISO is I did not want to introduce grain into my image and therefore I kept the ISO as low as possible. The second reason I did not adjust it was, the scene I was shooting in was not a low light scene. As discussed in this article, the ISO is used to compensate for low levels of light in a scene and as such this was not such a scenario.

This also tells us one thing. Just because you adjust one exposure setting, it does not mean that you have to adjust the other two as well. In most circumstances, you will adjust two exposure settings and leave one out. In other circumstances, you will have to adjust all three at the same time. It is all a matter of the scenario that you are in.

The Exposure triangle as explained is the relationship that exists amongst the exposure settings. This relationship guides us in making a decision in the final exposure that we want to achieve. A Stop as also explained is the amount of light captured in a scene. Understanding how to change stops and how to use them to determine exposure in different lighting scenarios will save you a ton of time while learning photography.

Stops are crucial in understanding the exposure triangle. The two concepts are interlinked and require one to take their time and practice as much as possible in order to have a firm understanding. I guarantee that once you have understood the exposure triangle and how stops work you are set for a home run.

If you still have questions or comments feel free to leave them in the comment section below. I will be taking my time to go through them and give answers and insight to your queries.

I’ll see you in another post. Bye.