The Exposure Triangle
A quick overview of the Exposure Triangle so you can take better images immediately!
What is the Exposure Triangle?
For those just starting out in photography, the Exposure Triangle put simply, is the relationship between your camera’s aperture, shutter speed, and ISO.
These three factors are at the centre of each image so understanding their relationship and how they compliment each other will help you determine how a picture will look before you take it.
Let’s take a quick look at each of the three components in the exposure triangle!
Aperture
This refers to the size of the circular hole created from the aperture blades in your lens and is arguably the most confusing of the three components.
To keep it simple, aperture has two main functions when it comes to taking photos:
dictating how much light is allowed to pass through the lens and into your camera’s sensor; and
determining how much of the background of your image is in focus or blurry (Bokeh).
When working in difficult light conditions, it’s super important to understand the first function as it will help you “brighten” or “darken” the image so that it’s exposed properly. However, this works in relation with the Shutter Speed and ISO which we’ll get onto later.
The second Aperture function gives you more artistic control over your desired image but of course, will affect the former. For example, if you’re a landscape photographer and want to ensure your whole image is sharp from front to back, you’ll want to set your Aperture to around f/9 or above. This will make the circular hole in your lens relatively small and stop a lot of light coming through. However, if you are shooting at night time, this may result in you losing some of the detail in your shadows and you may need to decrease your Shutter Speed to allow more time for the light to hit the sensor.
Alternatively, if you’re shooting portrait or wildlife photography and want that shallow depth of field where your subject is in focus and the background is all blurred, then you will want to shoot with an Aperture of around f/4 or below. However, this is going to let a ton of light into your sensor so to ensure your image is properly exposed and not blown out (where the highlights are all white), you will want to increase your Shutter Speed so it restricts the amount of time the light has to hit your sensor.
Starting to see the relationship now?
A big factor affecting your Aperture is the lens you use but that’s a whole other topic in itself so keep an eye out for that email.
Shutter Speed
So as you might have guessed already, this refers to how quickly the shutter in your camera opens and closes.
As mentioned above, it affects how much time light has to pass through your lens and onto your sensor but it also gives you loads of artistic creativity too!
For example, if you’re shooting a car driving by or your dog running and you want to capture that subject and make sure it’s not blurry, then by increasing your Shutter Speed to 1/320 (320th of a second), you’re camera’s shutter is going to open and close super quick stopping that action on the sensor.
Alternatively, if you’re shooting a waterfall and want to get that silky flowing look or to capture light trails, then by decreasing the Shutter Speed to 1/2 (half of a second) or slower, you’re going to capture the motion blur of the subject.
ISO
Without going into too much detail as this can get really technical and scientific, ISO essentially determines how sensitive the digital sensor in your camera is to light.
When shooting in low light situations at night or indoors, if you crank your ISO level up, it will create “fake light” and increase your image’s exposure. So say you’re shooting cars at night, you’ve got your aperture wide open (f/2) letting loads of light in and your Shutter Speed is at 1/250 to ensure the cars are sharp as they go by, if your image is still a bit dark and you want to brighten it more, you can increase your ISO to add “fake light”.
Now you might think this is great and you don’t need to worry about getting the best light conditions to take a photo but it does come at a cost. When you boost your camera’s ISO, it creates “noise” in the image which makes it look more grainy and pixelated - I always think it looks like TV static. The better the camera is, the more adept it will be to low-light conditions and can handle higher ISO settings but that means it will also come with a higher price tag.
For anyone just starting out in photography, it’s super important to learn the Exposure Triangle and each component’s relationship with one another so that you can take better photos in any situation and in any condition.
If your camera has the option to, put it in Manual Mode and take photos of the same scene whilst changing the value of an individual component incrementally one photo at a time.
This will help you understand the Triangle better and give you the confidence to look at a scene and know exactly what settings your camera needs to be at. You can also look back at old photos and see where you went wrong and how to correct it moving forward.
Have a great week!
