How your camera aperture works tips for beginners

The camera aperture is one of the most important adjustment options on your camera.

If you understand and master the aperture, photographing is much more fun. So, let’s get started right away.

In this lesson, you will learn camera aperture, among other things:

How to blur the background of your subject.
How the aperture is related to the exposure time.
How to adjust the aperture and use it for your photos.
We will first define the term aperture for you and explain its function as simply as possible. Don’t be put off if you don’t understand everything right away.

With each sentence here everything becomes a little clearer and after you have tried it practically, hopefully no questions are left unanswered. So, it’s best to take your camera right away.

For the basic understanding, a small preliminary remark:

There are two basic settings on how to influence the exposure of your photo. One of them is the aperture described in this lesson.

The second setting is the shutter speed, which is the duration of how long your image will be exposed. The longer the shutter speed, the more light falls on the sensor. We’ll discuss shutter speed in more detail in the next lesson. For this lesson, it’s enough if you know there’s shutter speed.

The aperture: A short definition

The aperture is the rear opening of your lens. You can control how large this opening is and determine how much light hits the camera’s sensor.

The size of the opening is indicated by the number of apertures. When a photographer talks about the number of apertures he used for a particular image, he uses numbers such as f/1.8, f/2.8, f/5.6.

The interesting thing now is that the higher the number behind the f/, the smaller the opening of the aperture. And vice versa: the smaller the number of apertures, the larger the opening of the aperture.

Take a look at the following picture. You can see that well there.

This means that when you set f/4, relatively much light hits your camera’s sensor, and when you set f/13, very little light hits the sensor.

What this is good for, we will explain to you later and then try it out practically. Then we also see where the differences are for photos with different apertures.

But first we have to work our way through the theory. Don’t give up! It will all make sense. So, back to the aperture number.

Burn this phrase into your brain: The smaller the number behind f/, the more light hits the sensor in your camera:

Small number, large opening, lots of light – large number, small opening, little light!

If that sounds illogical to you, imagine the numbers behind the f as a break. If we ask you if 1/16 (one sixteenth) is greater than 1/8, what would be your answer? No! Exactly. Just because the number 16 is greater, not 1/16 is more than 1/8. So: f/16 is less than f/8. f/16 thus lets less light in than f/8.

Tell yourself again: small number, lots of light – big number, little light!

Ok, take a deep breath. We move on.

This is a typical series of apertures:

camera aperture is one of the most important

The numbers you can set depends on your camera and especially on your lens. So it’s normal if the setting on your camera starts with a different aperture number or you have aperture numbers between the ones mentioned here.

Our standard lens has no small aperture numbers like f/1.4, f/2.0 and f/2.8. It only starts with an aperture of f/3.5.

Additional knowledge: aperture levels

If you want to delve a little deeper into the theory, then the additional knowledge about aperture levels is interesting for you. However, for the basic understanding of the aperture, you don’t necessarily need it and can skip it first and dedicate yourself directly to the practice in the following section.

You’re still there? Very good. Then let’s take a look at the following table:

Number of apertures	twice as much light as this Number of apertures	half as much light as with this Number of apertures
f/2.8	f/4	f/2
f/4	f/5.6	f/2.8
f/5.6	f/8	f/4
f/8	f/11	f/5.6
f/11	f/16	f/8

In the left column you will see different aperture values. The individual steps between two values are called aperture level. For example, if you reduce your aperture from f/4 to f/5.6, this is a difference from an aperture level.

With every whole aperture level, your camera’s sensor gets double or half as much light.

With an aperture of f/4.0, your sensor reaches twice as much light as an aperture of f/5.6, but only half as much as an aperture of f/2.8.

If you’ve been experimenting with the aperture a little bit, you may have noticed that your camera has more aperture levels than the ones shown in the table. For example, you can set an aperture of f/3.5 or an aperture of f/7.1 on your camera.

The reason for this is that there are also half aperture levels and third aperture levels. As a rule, you can determine in the menu of your camera whether you want to work with half or with third aperture levels.

So you have more than just the full aperture levels available. Of course, this does not change the connection between the aperture levels and the amount of light that falls on your sensor.

In the following two graphs you will see the respective rows of apertures with half and third levels, with all the aperture levels marked in bold.

Half aperture levels

Third aperture levels

Which of the two aperture levels you use is entirely up to you. Try both times and see which one you can get along with best. We have set third aperture levels for our cameras, as this allows us the greatest flexibility when taking pictures.

How to set the aperture on your camera

Enough theory, now let’s try out how to use the aperture in practice. It is best to take your camera to hand.

Mode A

Each camera has different modes. As a rule, the modes M, A, S and P are always included. For some cameras, the modes are called M, Av, Tv and P. To try out the aperture in practice, set the camera to mode A or Av. The abbreviation A stands for Aperture, the English word for aperture.

In mode A, you can manually determine your aperture count. So you can decide for yourself how much light you let on the sensor.

In mode A, your camera automatically selects the shutter speed that matches your chosen aperture number, so that your image is always properly exposed.

Mode A is also often called aperture priority or automatic shutter speed. Just choose which label you’d rather use, or just call it mode A.

You set the mode on a wheel on the top of your camera.

If you’re at the very beginning, you might be wondering now what the shutter speed has to look for here. Please don’t worry about it.

This is what the camera in mode A does automatically for you. We are now concentrating solely on the aperture number and mode A. We’ll take a closer look at shutter speed in the next lesson.

Now that you’ve set your camera to A mode, the next step is to set the aperture number you use to take your photo.

On many cameras, you control the number of apertures on a wheel in the front right of the camera. If you can’t find directly where to control the aperture on your camera, just check your manual.

To see what number of apertures you have set, you need to look through the viewfinder or on your display, depending on the camera type. There you will find the aperture number with the f/ at the beginning.

How to use the aperture for your photos

Now let’s take a look at how you can use the aperture for yourself and your photos.

Use the aperture: 1 photographing in low light conditions

We have already mentioned that the aperture determines how much light falls on your camera’s sensor. Reminder: large opening, lots of light – small opening, little light.

In low light conditions, you have the option to open your aperture wide and still leave enough light on the sensor to get a correctly exposed photo.

In the upcoming lessons, we will discuss shutter speed, manual exposure, and ISO. When you know all these terms and understand how they relate, much becomes clearer.

At this point, it’s enough to let you know that a large aperture can help you take pictures in low light conditions.

The following picture was taken, for example, in very low light conditions. Outside it was already dark and the scenery was only illuminated by many lanterns, which did not emit much light. So in this situation we opened the aperture wide to be able to take a photo anyway.

Aperture: f/2.5, shutter speed: 1/50 s, ISO: 400, focal length: 35 mm

Use the aperture: 2 depth of field or blurred background

But you don’t just use the aperture to determine how much light you’re letting into your camera. With the change of the aperture, you also have a very important stylistic means of photography in your hand: the depth of field. By choosing your aperture number, you determine whether the background of your main subject is crisp or blurred.

You’ve probably seen many photos where a person can be seen crisply, but the background is indistinct and blurry. This is exactly the effect you can achieve by using the aperture.

Of course we also have such photos. We picked out one of them.

In the image, the effect is much clearer. It is recorded with an aperture of f/1.8. Here, really only the incense stick in the foreground is sharp. The background can only be seen in a sketchy way.

Of course, you can also achieve the opposite effect by setting your aperture. By closing the aperture very far, i.e. selecting a large aperture number, you will achieve a very high depth of field. Instead of a blurred background, all elements of your image are sharp.

Which aperture is best?

Now, of course, the question arises as to which situation you should take pictures with which aperture. That is frankly a matter of taste. Nevertheless, we would like to give you a short guide, which aperture values can be useful for which situation.

Low depth of field is recommended whenever you want to focus on your main subject through a fuzzy background. This is the case, for example, with portrait photography. Low depth of field is possible with small aperture numbers between f/1.8 – f/4. There are even lenses that reach aperture numbers of f/1.4 and lower. However, they are usually very expensive.

But if you want to photograph not just one person, but a group of people, you have to work with a larger number of apertures, so you have to close the aperture further. It would be stupid if only the people in the front row were sharp and the people behind them were blurred.

By closing the aperture, you get more depth of field in the image and make sure that everyone in the image is sharp.

For example, you want to achieve a lot of depth of field in landscape photos, so that the landscape in the photo looks as truthful as possible. If you look at a landscape with your eyes, the foreground, the middle ground and the background are also sharp (unless you have left your visual aid at home).

In landscape photography, it is therefore recommended to take pictures with a closed aperture. By this we mean aperture numbers of z.B. f/11 or f/13.

But as we said above, it’s all a matter of taste. Imagine, for , you walk through the Sahara and suddenly see a beautiful red rose. Pretty unlikely, but who knows.

Now the Saharasand is somehow not so cool and you just want to put the focus on the rose. So you open the aperture completely (e.g. f/2.8) and focus only on the flower. This has the advantage that the beautiful rose is sharp, but the not so beautiful sand is but blurred.

But now imagine that the sand is so dry that great cracks have formed in the sand and in the middle of it blooms this beautiful red rose. In this case, the sand would be a great feature and could give your picture the last kick. So you want both the rose and your background to be sharp and take the picture with a brisk as closed aperture as possible (e.g f/11).

But beware:

You might be tempted to close your aperture extremely far now to get as sharp a sharpness as possible in your image. Unfortunately, this usually does not work. Although the depth of field actually increases as you close the aperture. At the same time, however, the general sharpness of the images decreases again from a certain number of apertures.

The number of apertures is not possible and varies from lens to lens. Each lens has a certain aperture value, where it achieves the greatest total sharpness. This is usually between aperture f/7.1 and f/11.

Our tip: Avoid too many aperture numbers to avoid blurry photos. At the latest from aperture f/16 it becomes critical with many lenses. An aperture of f/22 often significantly reduces the sharpness of the entire photo.

Exceptions confirm the rule as always. If you have some time, just take your camera and put it on a tripod. Now you simply take several photos from the same subject and always choose a different aperture.

Afterwards you can look at the pictures and find out which aperture your lens achieves the highest sharpness and from which number your images become blurred. This way you can find out exactly how far you can go with your lens.

Briefly summarized once again

Open aperture → e.g. f/1.8 or f/3.5 → Low depth of field → e.g. in portraits and all situations where you just want to focus on your main subject and the background should be blurred.

Closed aperture → e.g. f/11 or f/13 → High depth of field → e.g. in landscape photography, or axe photography and all situations in which you want to have your image sharp from foreground to background.

Additional knowledge: Full control over depth of field

The aperture is actually just one of three factors you can use to influence or control the depth of field in your image. In the lessons to come, this will become even clearer, but for the sake of completeness we would like to mention it here.

That’s why we’re making a little excursion to depth of field at this point. If you only want to deal with the aperture at first, you can also skip this part and read it to you later.

So here are all the factors at a glance that have an impact on depth of field:

The aperture

The focal length of your lens (wide angle vs. telephoto lens)
The distance from your camera to your subject

Let’s start with a small but fine overview of how the factors affect the depth of field in your image:

We have already clarified the connection between aperture and depth of field. Let us now look at the other two factors.

Keyword: focal length

We will discuss the focal length in one of the next lessons. To understand this section, therefore, a really very, very short explanation: The focal length corresponds to the zoom of your camera: short focal length = low zoom = wide angle and long focal length = a lot of zoom = telephoto lens.

If you take pictures with a wide angle lens, you still have a relatively high depth of field in the image even with a wide open aperture. The following image of Basti in action was photographed .B with a relatively wide open aperture of f/4.

However, since it was photographed with a short focal length of 18 mm and the distance to the subject was relatively large (see next point), this photo still has a relatively high depth of field.

But if you’re shooting with a telephoto lens, it’s the other way around. Even if you take pictures with an already quite closed aperture, you will still have a relatively low depth of field in the image.

You can see that very well at the next picture. Although it was recorded with a relatively closed aperture of f/8, the background is blurred. This is because it was recorded with a very long focal length of 300 mm, i.e. a very large zoom.

Keyword focal length — Aperture: f/8, shutter speed: 1/400 s, ISO: 800, focal length: 300 mm

Keyword: Distance motif/lens

When you take a portrait photo and your model stands half a meter away from you, the background becomes very blurry. If you take a big step back now and take another photo with the same settings, the depth of field is not so low anymore.

As you can see, it’s not just the aperture that’s responsible for the depth of field.

Practical tasks

Sun. Now let’s try it out. We hope you have your camera at hand. You need them.

This is what you need for your first practical tests:

Your camera

Your camera’s manual if you’re not sure how to change the number of apertures on your camera
A motive. Maybe you have a little cuddly toy or something similar that can be used as a model.

You can easily do the first exercises at home.

Make sure you have a lot of light at your disposal. This also applies to photos in your apartment. It’s best to turn on all the lamps you have at your disposal.

After you turn on the camera, you set the wheel to aperture priority – mode A (or Av on some cameras). Now, when you look through the viewfinder or on your display, you’ll see several numbers glowing at the bottom of the screen. One of them should have a f before. Found? That’s the number of apertures.

Now you look through the viewfinder and focus on your motive. To set the aperture number, you must first press the shutter button briefly and focus your subject. You can then use the wheel to change the number of apertures.

1 Familiarize yourself with the setting of the aperture on the camera

For setting the aperture number, it depends a bit on which camera you have. Trying out usually helps. Often there is a small cog in the front right of the camera. This allows you to change the number of apertures.

If you don’t have this wheel, just try which wheel changes the aperture number for you or, if necessary, just look at the manual. Found? Prima! You have already successfully passed the first task!

2 Discover the effect of the aperture setting

So, now we are taking pictures. Just look for a motif and take pictures with different aperture numbers.

Try the entire scale of the aperture once, i.e. also very wide open and very closed apertures. Do you see how your subject and background changes?

If you select very large aperture numbers, you probably need to place the camera on a tripod or place it on the table. Since very little light falls on the sensor due to the very small aperture, your camera tries to compensate for this with a long shutter speed, which can cause your images to shake. You can learn more about shutter speed in the next lesson.

3 games with depth of field

Once you’ve become familiar with the setting of the aperture on your camera, try using the depth blur consciously for your images. Choose the largest possible aperture of your lens (smallest aperture number) and look for subjects that look good with a fuzzy background.

Photograph the subject from different distances and see how this affects your background.

Did you understand the aperture? Super! This is already a very big step on the way to learning to take pictures. In the next lesson, we’ll look at shutter speed, the second very important setting on your camera.

Did you like our explanation of the aperture?