Understanding the exposure triangle requires you to have a firm grasp on aperture, shutter speed and ISO. These three settings make up the exposure triangle. In this post we will be diving into just one of these settings and that is aperture.
Each setting is extremely important to create a properly exposed, sharp photo. The key is making sure you understand how to get them to work together to create the photo you want. So let’s get started on the first key element in the exposure triangle.
Read more: 3 Steps for Perfect Exposure for Every Photo
Table to Contents
What is aperture?
Aperture is the hole or opening in which light travels through. It determines not only how much light to bring in, but also how much of your image is in focus. Aperture is the actual opening of the lens’s diaphragm.
What is f-stop?
Aperture and f- stop are very similar. Sometimes aperture will be written and talked about in the term “f – stop,” which is written like f/. That term is followed by a number like 1.2, or 5.6 etc. So you will hear photographers say “I had my f-stop at 3.2.” Or they will write it like this “In this photo, my aperture was f/3.2.”
How aperture affects light
Lower number means more light allowed
If you want to bring more light into your photo, you will want to shoot with a smaller number. This is often referred to as “opening up your aperture.”
For example if I need a light to find something in the dark, I am going to get a larger flashlight rather than using a laser pointer. If I need more light in my photo, I will open up to a lower number.
The diagram below illustrates that.
Larger number means less light allowed
To decrease the amount of light coming into your image you will use a higher aperture setting. This is referred to as “closing your aperture”.
Maybe the sun is very bright in the sky and I don’t need all of that to properly expose my photo, I will close to a higher number so less light is allowed in my photo.
What does aperture do?
Besides affecting the light in your photo aperture also plays a large roll in how sharp your image will be. It determines how much of your photo is in focus and how much is blurred.
Creates a beautiful blurry background
The thing I love most about setting my f/ wide open is creating those blurry backgrounds that make photos look more professional.
If you have ever looked at a photo where the subject is tack sharp but the background is blurry, this is created by their choice of aperture. These type of photos really make the subject pop.
Read more: Master Depth of Field with 4 Simple Tips
Smaller number = less in focus
The smaller the aperture number like f/ 1.2 and f/ 2.8, then less of the photo will be in focus. That means you will have that nice blurry background.
Plus, if you are shooting in your house and have your aperture wide open it helps to hide the mess that may be in the background. That is one of my favorite tricks for capturing real life without all the mess.
The larger the number like f/11 or f/14, then more of the photo will be in focus which is perfect for group photos.
Read more: 6 Tips to Improve your Background
Shooting “Wide Open”
Another thing to keep in mind about when people talk about aperture or f stops is they say they are shooting “wide open” or a “narrow” or “smaller aperture.” When people say they are wide open or to “open up your aperture” they mean to lower your number.
For example, if you are shooting at f16 and you open up your aperture you would change it to a lower number and like f1.8. If you want to shoot wide open you would change it to the lowest number possible depending on your lens.
Read more: 6 Reasons Why You Have Blurry Photos
Which aperture is best?
Depending on what photography style you are going for, you will find that one aperture range works best for you. Some people need a very low number to make their subject pop and stand out from a blurred back ground. While others will need everything in focus to really capture the scene.
Aperture really depends on your lens too. I wrote an entire post about Finding Your Perfect Lens.
Portraits use wider apertures
Portrait photographers like to use a low f/ number to draw the attention to the subject and nothing else. Having the subjects eyes in focus with a blurry background creates a beautiful and professional looking image.
Landscape photography use closed apertures
If you are trying to capture a beautiful landscape shot you are probably going to want everything in focus. You want to see the clear lake, the sharp trees, and the fluffy white clouds. If your aperture is too low, not everything will be in focus. So a closed aperture like f/14 or more will be what you use.
Read more: Elevate Landscape Photography with Light
Examples of different apertures
Here are a few examples of what a picture will look like using different aperture settings. I started wide open at f/1.4.
Notice how in the ones where my f/ was wider (smaller number) there is some great bokeh and as my aperture was more closed up you can see all the details in the background.
Frequently Asked Questions
They both have their place in photography. First determine how much light you need in your photo. Then decide how much of your image you want in focus. That will help you determine what will be the best aperture for your shot.
This is a number on the aperture scale. It usually means a smaller focal plane with a blurrier background. This f/ will let in a lot more light as well.
The lower the f/ number, the better. If it is a solo shot, f/ 1.8- f/2.8. Then based off of how many people & if they are on different focal planes, go up as necessary.
You want the majority of the scene in focus for landscape shots so you are going to want to keep your f/ at 10 or higher.
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