Understanding F-Stops In Photography And How To Use Them (2024)

What Are F-Stops?

To make it as simple as possible, an f-stop is a setting on your camera which specifies the aperture of your lens when taking a photograph. The f-stop is represented using numbers such as f/1.4 or f/5.6 – some of the most common f-stops. The “f” in f-stop stands for focal length, referring to your lens.

To make it more complicated, the f-stop is also known as the aperture. The f-stop is a setting that will regulate the amount of light that passes through your lens at a predetermined shutter speed. This means that a smaller f-stop is going to let in less light than a larger f-stop. It’s a smaller aperture vs a larger aperture. The f-stop is the setting for the aperture. F-stop and aperture are essentially the same thing.

What is Aperture?

To understand how to properly use f-stops, we need to take a closer look at what exactly the aperture is. The aperture by definition is the hole in your camera’s lens that appears when you click the shutter button and the shutter opens to take a picture. Think about the aperture as a window. The bigger the aperture is, the bigger the window to your camera would be and the more light will be captured.

In the case of a camera, the aperture is always circular. Manual cameras produce circular apertures by blades that form a ring around the lens of the camera. In other words, a large aperture will have a wider diameter and a small aperture will have a shorter diameter.

Different lenses can produce different aperture sizes. A lens does not only impact the size of your aperture, but also its diameter. The size of the aperture determined by your camera’s lens is measured as an f-stop.

What is Aperture Used For?

Different apertures are for letting in different amounts of light. Experts often compare an aperture to an hourglass. The size of the aperture, just like the opening between the two chambers of an hourglass, dictates how much light will reach the sensor of your camera.

With a small aperture, almost no light will move through the shutter and into the camera. This is the same as having an extremely thin opening between the two chambers of an hourglass, hardly letting any sand pass from the top to the bottom.

What is the F-Stop Used For?

The f-stop is used to represent your current aperture setting. There is an aperture scale represented by a series of progressing f-numbers. This is one of the trickiest things to understand. What you need to know is that smaller numbers mean a larger aperture setting while larger f-stop numbers translate to a smaller aperture setting.

What Do F-Stop Numbers Mean?

The f-stop numbers can be read in a scale of decreasing apertures. Not all these numbers match across all types of photography equipment. Sometimes, they depend on which camera you have. That being said, all the f-stop numbers will represent a setting for the aperture relative to your lens’s maximum aperture. The larger f-stop numbers will still decrease the light entering your camera lens.

The following are the most common f-stops on the aperture scale:

f/1.4
f/2.0
f/2.8
f/4.0
f/5.6
f/8.0
f/11.0
f/16.0
f/22.0
f/32.0

F/1.4 is the largest aperture setting and works to let in the maximum amount of light. The next setting of f/2.0 lets in half as much light as f/1.4, while f/2.8 lets in half as much light as the previous f/2.0. That’s how the scale progresses.

F/32.0 is the smallest aperture that you’ll likely ever use. It should only be utilized when you need to let almost no light into your camera’s sensor.

F-stops are fractions of the focal length being used. If you want to properly calculate your aperture size while using a specific f-stop, you need to divide the focal length by the setting. For example, a 200mm lens using an f-stop of f/4.0 means the total diameter of your aperture is 50mm. In other words, it’s ¼ of the lens.

Continuing with this, a 50mm lens that has an f-stop setting of f/2.0 means the lens opening is 25mm. A 50mm lens with an f-stop setting of f/8.0 has a lens opening of only 6.25mm wide.

How Does F-Stop Affect a Picture?

Your f-stop setting can affect the outcome of your photograph in a variety of different ways. The biggest is going to be with light. You need to learn which apertures make more sense in what lighting conditions to capture the photograph you desire.

For example, using a massive aperture on a bright and sunny day is going to result in a huge amount of light being taken in by your camera sensor. This creates a picture that appears washed out and fuzzy. The exact opposite happens at night. Using a large aperture while taking photos in the dark means that your pictures will be adequately lit with your subjects visible. The less light there is, the larger the aperture you need.

Of course, it takes a lot of practice to get this right. As you journey to becoming a professional photographer, you will get the hang of which apertures to use in which lighting conditions to achieve unique effects.

Another thing you need to know about f-stops is that they work with shutter speeds to bring light into a photograph. The shutter speed determines how long the lens of your camera stays open and the f-stop determines how wide that opening is. These two aspects have a huge impact on one another.

The key thing to understand here is that even if you have a wide aperture, a fast shutter speed can reduce the amount of light in an image. A very small aperture using a much slower shutter speed will actually let in more light than you may think. These are the kinds of factors you need to consider when taking professional photographs.

Which F-Stop is Best?

There is no perfect f-stop. The best f-stop to use is going to change constantly depending on your settings and what you want the final product to look like. To be honest, figuring out the best f-stop to use in a particular situation can only come with much practice and experience.

But through experimentation, you can come to understand how to properly implement the f-stop setting. It’s no different than mastering the other settings on your camera, like ISO and depth of field. A lot of your choices are also going to depend on your artistic choices as a photographer.

All that being said, there are some general rules you can apply when mastering f-stops.

You always want to use a smaller aperture (a higher f-stop) when it’s bright and sunny outside. When there is ample light, your aperture needs to be smaller so that you don’t wash out your image. On the flip side, always go with a wider aperture (a lower f-stop) when there isn’t sufficient light. This includes nighttime or inside in the dark.

It’s also important to know that if you add a flash, you’ll need a smaller aperture. The flash on your camera is an excellent source of light and needs to be considered in conjunction with the natural sources of light around you.

Large apertures are ideal for portrait photography when the subject is clear but the background is blurred. This is actually how you get the much-desired bokeh effect. With a larger aperture, you get a shallower focus. This means an attractive depth of field effect with things like headshot photography. In fact, the bokeh effect can even be seen on smartphones when taking pictures using portrait mode.

If you’re interested in having your foreground subject and your background being equally in focus, a smaller aperture is better. A smaller aperture (higher f-stop) will create a more balanced photograph and remove the bokeh effect.

Final Thoughts

The f-stop is a setting for your aperture. The aperture is how open your camera shutter is when taking a picture. Always remember that the higher the f-stop number, the smaller the aperture. The smallest f-stop setting will be the most open your aperture can be, resulting in maximum exposure to light.

But there is more to taking photographs than just the f-stop numbers and your aperture. Professional photographers understand that there are many components that go into the final photograph taken. You have to consider focal length, intensity, and direction of a light source, the shutter speed, the appropriate f-stop, and of course your ISO settings.

These are aspects that you will learn to master on your way to becoming a pro photographer.