What Is Aperture?

If you want to learn more about aperture, then you’ve come to the right place!

Trevor Holmes


What is aperature?

Let’s start at the very beginning: What is aperture? Great question! Aperture is often referenced in optics — a branch of physics focused on the study of light. In optics, aperture is the name for a hole through which light can travel.

But, aperture doesn’t only matter in physics. It affects how your video looks and even how the tone of your video feels. So, how does this light-controlling hole affect your videos? Let’s dive in and learn more!

What is the aperture on a camera?

The aperture on your camera is a hole in the lens that controls the amount of light that passes through the camera lens to fall on the sensor.

Think of it like your eyes: When you squint, less light comes through to the pupil, and when the eye is opened fully, all of the light enters.

Something to keep in mind is that the aperture on your camera not only affects the brightness or exposure of your image, but it affects depth of field, too.

What is an f-stop?

The aperture setting is typically identified by an f-number, often called an f-stop, which is a ratio comparing the focal length to the effective aperture diameter.

A wide aperture has a lower f-stop, so more light will come through the lens (smaller number = larger hole).

A small aperture has a higher f-stop, so less light will come through the lens to reach the sensor (larger number = smaller hole).

Make sense?

What is depth of field? Depth of field (DOF) refers to the amount an image is in or out of a focus. A shallow DOF is when the subject is in focus but the background and foreground are out of focus. A deep DOF is when the background and foreground are in focus and the subject is out of focus. A shallow DOF is generally more desirable.

Is it better to have higher or lower aperture?

There are benefits to having either a higher aperture or a lower aperture. It all depends on what kind of look you are going for — because high and low apertures create distinct looks that help you dial in that “sweet spot” for your style.

A higher aperture (e.g., f/16) means less light is entering the camera. This setting is better for when you want everything in your shot to be in focus — like when you’re shooting a group shot or a landscape.

A lower aperture means more light is entering the camera, which is better for low-light scenarios. Plus, lower apertures create a shallow depth of field, making the background blurry. You want to use a low aperture when you want a more dynamic shot. For example, we use low apertures like (f/1.8) in our Wistia studio to create that cinematic look.

When you’re setting up for a shot, keep this tip in mind:

  • The higher the number, the more of your shot will be in focus.
  • The lower the number, the less of your shot will be in focus.

What does the f-stop number, e.g. F1.4 mean?

Simply put, the f-stop number is tied to aperture. The higher the f-stop number, the smaller the aperture, which means less light enters the camera. The lower the f-stop number, the larger the aperture, and the more light enters the camera.

So, f/1.4 means the aperture is pretty much all the way open, and lots of light is entering the camera.

You might be wondering why f-stops are displayed using decimals (e.g., 1.4, 2.8, and more). Well, that’s because they’re a fraction that stands for the ratio of the focal length of a lens to the diameter of the entrance pupil.

Basically, f-stops are a quantitative measure of the lens speed and are often specific to what type of lens you’re using. For example, some lenses don’t go below an f/4 and others can go down to an f/1.2.

Traditionally, a lens that goes below an f/4 is classified as a “fast lens,” which refers to the maximum aperture diameter (or f-stop).

How do you use aperture?

When it comes to physically using aperture on your camera, adjusting your aperture should be simple! Every camera has an f-stop number digitally displayed on an LCD screen, or on the dialog box on the top of the camera.

To increase or decrease the aperture, simply adjust the camera’s circular jog wheel. If all else fails, check your camera’s manual!

As for how you should use aperture in the context of your shot, here are a few considerations:

Is your background messy?

If your background is messy or busy, it can be distracting for the viewer and pull their attention away from the subject of your shot. Use a low aperture to blur your background! Stick to as low of an aperture as possible to focus on your subject and keep the background blurry.

Is this a portrait?

If so, you may want to use a lower aperture (f/1.8). The lower the number, the more shallow the depth of field. Less things will be in focus, and the setting will create a dynamic-looking shot.

Is this a landscape?

If you’re shooting landscape, you may want to use a higher aperture (f/16). With a higher aperture, more things in the shot will be in focus.

What is it that you are shooting?

If you’re still fuzzy on what setting to pick, go ahead and try a couple of shots! Take a couple shots at one f-stop, and if you don’t like that look, adjust accordingly.

The beauty of DSLRs is that you can play around with your aperture and instantly see the results to find just the right setting for what you’re trying to achieve.

What aperture should you use for video?

You can use many different apertures for recording quality video. If you’re familiar with photography, aperture for video follows the same rules you’re already familiar with.

Aperture is one of the three main adjustments for exposure/brightness on your camera, with the others being shutter speed and ISO. Setting the right aperture also depends on what the shutter speed and ISO are set at; they all work together to create one balanced-looking shot.

Aperture for video follows the same rules as aperture for photography:

  • Higher the number = darker the image
  • Lower the number = brighter the image

Most importantly, you have to consider the context: What is it that you’re shooting?

Here are some examples: If your subject is running or moving a lot, then you probably want a higher aperture where more of the scene is going to be in focus, so your subject doesn’t become blurry.

Now, if you’re shooting a closeup of something extremely cute and still, like a closeup of a sleeping dog, then you’ll want to crank that aperture all the way down. With a lower aperture, you’ll be able to have a dynamic depth of field in your shot.

Finally, with autofocus tracking recently taking over the DSLR game, you don’t have to worry too much about your shot being in focus, but these rules above still apply when properly exposing for a shot.

What is the best aperture?

The best aperture is … well, all of them!

Most people will probably say lower apertures are the best. That’s because, in a lot of cases, more expensive lenses typically have lower f-stops (e.g., 1.2, 1.4, 3, etc) and a more expensive lens can sometimes equate to better quality. For example, prime lenses (i.e., those with a fixed focal length), like a 24mm, 35mm, or 50mm, can have apertures as low as 1.2 and can create some dynamic looking shots.

That said, the best aperture is truly relative to the lens.

Here’s what we mean by that: Each lens is different and has different characteristics. So, depending on whether you use a macro, zoom, prime, or telephoto, one setting is going to look different across each one of these lenses.

Some zoom lenses have a fixed aperture throughout the range of the zoom. These lenses include a 24–70mm f/2.8, a 24–105mm f/4.0, and a 70–200mm f/2.8. Some newer lenses even have a lower aperture, like the 28–70mm f/2.0. These lenses tend to be more expensive than zoom lenses with a variable aperture. An example of a lens with a variable aperture is an 18–55mm f/3.5–5.6. This means that as you zoom in, the aperture gets smaller, and the number gets bigger.

At the end of the day, when it comes to aperture, the main thing to remember is that it controls how much light comes into your shot — and you want to use that knowledge to choose the best aperture based on the context of what you’re shooting.

Trevor Holmes


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