What is Aperture, How it Works and How to Use it

Understanding f-stops is important to creating stunning photos like this one. As a beginner photographer, you may have heard terms like f-stop or f-number and wondered what they actually mean.

In this article, we’ll dive into these in detail and talk about how to apply them to your photography. Why Aperture Matters As we’ve already defined, aperture is basically a hole in your camera lens that lets light through.

This is not a particularly complicated subject, but it helps to have a good mental concept of aperture blades. Yes, aperture shutters, also known as diaphragms in optics. Look inside the camera lens.

If you shine the light at the right angle, you’ll see something that looks like this: these blades form a small hole, almost round in shape – your aperture.

They can also open and close and change the size of the aperture. This is an important concept!

You will often hear other photographers talk about large and small apertures.

They will tell you to “stop” (close) or “open” (widen) the shutters for a particular photo. As you would expect, there are differences between photos taken at a large aperture and photos taken at a small aperture. .

Aperture size directly affects the brightness of a photo, with larger apertures letting more light into the camera compared to smaller apertures.

However, this is not the only thing that is affected by the aperture. Another major influence is depth of field – the amount of your photo that looks sharp from front to back.

For example, the two images below have different depth of field depending on the aperture size: Adjusting the aperture is one of the best tools you have to capture the right images.

You can adjust it by putting the camera into aperture priority mode or manual mode, both of which let you choose any aperture you want.

That’s why I always only shoot in aperture priority or manual mode! Before you try it out for yourself, there are a few other things you might want to know. What is F-Stop? F-Stop, also known as f-number, is the ratio of the focal length of a lens to the diameter of the entrance pupil.

In very simple language, f-stop is the number that your camera shows you when you change the aperture size of the lens. You may have already seen this in your camera.

On the LCD or in the camera’s viewfinder, the f-stop looks like this: f/2.8, f/4, f/5.6, f/8, f/11, etc.

These are just examples of different f-stops, and you may come across much smaller numbers like f/1.2 or much larger ones like f/64. Aperture is marked with f numbers.

If you ever read an article online that ignores this simple fact, you will be very confused. Pop quiz: Which aperture is bigger – f/8 or f/22? You already know the answer to this question, because the aperture is a particle.

So, f/8 is a larger aperture. If someone tells you to use a large aperture, they recommend an f-stop like f/1.4, f/2, or f/2.8.

If someone tells you to use a small aperture, they recommend an f-stop like f/8, f/11, or f/16. To understand, take a look at the diagram below showing the different aperture sizes: As you can see, an f-stop like f/2.8 represents a much larger aperture opening than something like f/16. What does the “f” stand for? Many photographers ask me an interesting question: What does the “f” stand for in f-stop or in the aperture name (like f/8)? Simply, “f” stands for “focal length”.

When substituting the focal length into a fraction, solve for the diameter of the aperture blades in the lens.

(Or, more accurately, the diameter the blades appear to be when looking through the front of the lens). For example, say you have an 80-200mm f/2.8 lens that is fully zoomed out to 80mm.

If your f-stop is set to f/4, the diameter of the aperture blades will appear exactly 20 millimeters (80mm / 4) in your lens, while at f/16 the diameter will be reduced to just 5 millimeters (80mm). / 16).It’s a cool concept.

Physically, at f/4, the aperture blades are opened much wider, as shown below: What F-stop values ​​can you actually set? Unfortunately, you can’t just set the desired f-stop value.

At some point, the aperture blades in your lens won’t be able to close any less, or they won’t be able to open any wider. Typically the “maximum” aperture of a lens, often referred to as the “wide open” aperture, will be approximately f/1.4, f/1.8, f/2, f/2.8, f/3.5, f/ 4 or f/5.6. Many photographers are really interested in the maximum aperture that their lenses offer.

Sometimes they will pay hundreds of extra dollars just to buy a lens with a maximum aperture of f/2.8 instead of f/4 or f/1.4 instead of f/1.8. Why is a large maximum aperture in a lens so important?

Because a lens with a larger maximum aperture lets more light into the camera.

For example, a lens with a maximum aperture of f/2.8 lets in twice as much light as a lens with a maximum aperture of f/4.0.

This difference could be a big deal when shooting in low light conditions. Since maximum aperture is very important to people, camera manufacturers have decided to include this number in the name of the lens.

The maximum aperture it offers is f/1.8. I took this photo at f/1.8 with a Nikon 20mm f/1.8 lens.

With a large aperture (and tripod), you can practically see in the dark. If you have a 50mm f/1.4 lens, the maximum aperture you can use is f/1.4.

Professional constant aperture zoom lenses such as the 24-70mm f/2.8 will have a maximum aperture of f/2.8 at each focal length.

For cheaper consumer lenses such as the 18-55mm f/3.5-5.6, the maximum aperture will change depending on the focal length.

In between, there is a gradual shift from one to the other. Photographers generally don’t care much about the smallest or “minimum” aperture that a lens allows, so manufacturers don’t put that information in the lens name.

The minimum aperture of a lens is usually around f/16, f/22 or f/32. F-stop and depth of field, in addition to the amount of light that the lens aperture allows, has another big effect on your photos – depth of field. I always find that depth of field is easiest to understand by looking at photos like the comparison below.

In this example, I used a relatively large aperture of f/4 for the left photo, and an incredibly small aperture of f/32 for the right.

Any part of your photo that intersects with the window glass will be sharp.

The thickness of the glass varies depending on your aperture.

Also, depth of field decreases gradually rather than dropping off sharply, so the window glass analogy is definitely a simplification. This is why portrait photographers like f-stops like f/1.4, f/2 or f/2.8.

If you want a shallow focus effect, set a large aperture such as f/1.4.

That’s what I used here to capture the eyes of this cat as sharp as possible while rendering the background very blurry.

(This also works for portraits or any other subject.) On the other hand, you should see why landscape photographers prefer f-stops like f/8, f/11, or f/16.

If you want your entire photo to be sharp to the horizon, this is what you should use. It might not be as exciting as taking pictures of cats, but I still love it!

Each step down lets in half as much light: f/1.4 (very large opening of the aperture blades, lets in a lot of light) f/2.0 (lets in half as much light as f/1.4) f/2.8 (lets in half as much light than f/2.0) f/4.0 (etc.) f/5.6 f/8.0 f/11.0 f/16.0 f/22.0 f/32.0 (very small aperture, almost zero light) These are the main “stop” apertures, but most cameras and lenses today allow you to set some intermediate values, such as f/1.8 or f/3.5. To see this information in a table, please choose: f/1.4f/ 2.0f/2.8f/4.0f/5.6f/8.0f/11.0f/16.0f/22.0Very large apertureLarge apertureLarge apertureModerate apertureModerate apertureModerate apertureSmall apertureSmall apertureVery small aperture Lets in a lot of lightHalf less lightHalf less lightHalf less lightHa if like a lot of light (very “medium” aperture) Half less lightHalf less lightHalf less lightHalf less light (making your photos very dark)Very thin depth of fieldThin depth of fieldThin depth depth of field Moderately shallow depth of field Moderate depth of field Moderately large depth of field Large depth of field Large depth of field Very large depth of field Typically, the sharpest f-stop on a lens will be somewhere in the middle of this range — f/4, f/5,6, or f/8.

However, sharpness isn’t as important as things like depth of field, so don’t be afraid to set other values ​​when you need them.

There is a reason why your lens has so many possible aperture settings. Other F-Stop Effects Page 2 of our Aperture article dives into every single Aperture effect on your photos.

It includes things like diffraction, sun stars, lens aberrations, etc.

While all of this is important, it’s not what you need to know—especially in the beginning. Instead, know that the two biggest reasons to adjust aperture are to change brightness (exposure) and depth of field.

They have the most obvious effect on your images, and you can always read about the smaller effects later. Conclusion Hopefully you now have a good feel for f-stop and the ways it affects your photos.

In summary: F-stop (or f-number) is the number you see on your camera or lens when you adjust the aperture size.

Because f-stops are fractions, an aperture of f/2 is much larger than an aperture of f/16.

Like the pupil of the eye, a large aperture lets in a lot of light.

If it’s dark outside and you don’t have a tripod, you’ll want to use a large aperture, around f/1.8 or f/3.5.

Your lens has a maximum and minimum aperture that you can set.

For a lens like the Nikon 50mm f/1.8G, the maximum aperture is f/1.8 and the minimum aperture is f/16.

In addition to the amount of light passing through the aperture, it also affects depth of field – how much of the image appears in focus.

Large apertures like f/1.8 have a very shallow depth of field, which is why portrait photographers love them so much.

Landscape photographers prefer to use smaller apertures such as f/8, f/11 or f/16 to capture the foreground and background of the scene as sharply as possible at the same time.

There are other effects of aperture, but exposure and depth of field are generally the most important. That’s it!

If you understand the basic points, you have the basics of f-stop and aperture. Of course, putting everything into practice is another matter.

Even if this entire article makes sense for now, you’ll still need to take hundreds of photos in the field, if not thousands, before these concepts become fully intuitive. Fortunately, you have the building blocks.

Aperture and f-stop aren’t complicated topics, but they can seem a bit contradictory to photographers just starting out.

Hopefully this article has cleared up some of the confusion and you now have a better understanding of aperture basics. Below are some examples of photos taken at various f-stops from f/2.8 to f/16 to give you an idea of ​​how they are used in the field: Taken at a large aperture of f/2.8, which provides a shallow focus effect. Shot at f/8, relatively medium aperture.

Since there was no foreground right next to my lens in this case, every part of this image (from front to back) is very sharp. Shot at a small aperture of f/16.

Here my foreground was so close to the lens that I needed a huge depth of field.

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