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Aperture Explained

Today, we’re going to dive deep and explain how Aperture works , best uses, and totally dominate it to your advantage to get the photos you want. Friends, it’s going to get owned today. Hard.

hello my friends today we’re gonna be talking about what aperture is in digital photography so let’s first start off with what is the difference between aperture and f-stop a lot of people get this confused so we’re gonna really make and make an effort to clarify that right now so aperture and photography refers to the maximum opening of the the though the width of your lens so in here there’s something called the diaphragm I don’t have a manual focus lens so I can’t actually show you as a demonstration how it actually changes this is only done through software by changing a setting in my camera that functions to change that electronically but what you’re changing when you win or what you’re what we refer to when we say apertures the maximum opening of the diaphragm or or the diameter of the lens the lens opening and then f-stop on the other hand is a setting within the overall range of your lens so for example right here so I have a the 50 millimeter 1.4 DG Sigma art lens the aperture for this lens is 1.4 that is the maximum aperture of this lens now if I set the the lens through my camera to f/4 as an f-stop that’s a specific setting in the range of this lens this rate this lens goes from f-14 to f-22 and that right there is an f-stop so the reason why it’s called an f-stop it’s really just an act like epic aperture has just been notated as an ephah and italicized F I don’t know the whole background behind why it’s F maybe it’s a Greek symbol I’m not entirely sure but when it said when we’re referring to f-stop we’re referring to a specific setting and F for an aperture stop in in the range of the camera specifically range of a lens so a lot of beginning photographers really make that mistake of really not understanding what aperture versus f-stop is f-stop again is really just talking about this specific setting of an aperture in the lens so when he when you I guess the biggest thing I could really say on that to really that’s super super clear think aperture maximum think f-stop setting just to kind of clarify that hope that helps on that one so what happens when you make a change to aperture and you actually make a change in your adjusting the f-stop of your aperture whether it be like through a ring that would be manually on a manual focus and a manual lens or electronically through just the camera itself what you’re actually changing and what you’re selecting is a photographer is going to be what’s the size of the diet the diaphragm or the diameter the opening of the lens and we get to choose that so the chattin the sizes that we can pick are gonna range typically from point 0 naught or 0.9 sometimes 0.65 all the way to F 32 f 36 at 40 a lot of lenses do not go that far a lot of lenses do also do not go that wide open either both most lenses typically that you’ll see out right now will be between F 1.4 maybe 1.2 to f-22 f-35 I’d open or or more narrow in aperture those lenses are gonna be very expensive but they do exist so when you have a smaller or a more narrow opening as far as the size the aperture what that what that means is that the the opening is getting smaller so there’s gonna be a greater depth of field meaning the distance between where your subjects is in the front most point of focus and the back most point of focus are going to be like it’s gonna be larger so that basically means that you’re gonna be able to have more of your photo in focus if the narrow if there’s more of a narrow or smaller aperture which in this case a narrow aperture is going to refer to a higher f-stop number it’s just an inverse relationship so as the number gets larger because it’s fractional and it’s referring to the size of the opening as the the fractional value so f let’s just say F SAS symbol over like 100 that’s gonna be a smaller opening than over one which is gonna be a larger opening for some terminologies to kind of help you guys get started as well when I say opening up or stopping down the lens it’s referring to how wide or narrow the opening of aperture actually is so when someone says hey open up your lens 2f 1.4 for example F 1.8 what they’re saying is adjust your aperture your f-stop settings so that it’s the smallest number so for example 1.8 so that the diameter of your of your lens is actually larger or it’s the largest in that case that could be the maximum aperture and 1.4 for this lens or could be 1.8 for your lens and if they say hey stop down your lens a little bit you’re letting a little bit too much light in they’re referring to you to actually closing down the aperture which means that they’re asking you to increase the f-stop number to say F for 5.6 or f/8 or f/11 f-16 f-22 that’s what that’s referring to that’s a little bit of nomenclature that you’ll see all the time and that’s referring to opening up or closing down so opening is big closing down is small what happens when you have a more open or a wide open lens in your ear a little bit further down when it comes up f-stops and you’re at a smaller number that means you’re gonna have more shallow depth-of-field more shallow depth-of-field means the distance between the front focus in the back focus from where you’re actually focusing whether you’re doing automatic focus or you’re doing manual focus that’s gonna be very very small in some cases if you’re shooting at 1.4 like this lens is able to do and you’re shooting in a situation where you’re you’re very close to your subject only the eyes in a lot of cases will actually be in focus if you start to step back maybe it’ll be maybe the eyes and the nose and maybe a little bit of ellipse maybe if you move back a little bit further it may be all the way to the ears at 1.4 but that distance is very very small and then as you you increase the f-stop and you actually close down your aperture so we get smaller and smaller that that distance increases increase in increases and that’s the second point that’s very sequential in nature as far as every time you change a setting and you increase that value is just gonna get bigger and bigger that’s just how it works so so what happens as really as the narrow as aperture narrows so that means less light is gonna get to your sensor because you have the thing about light as water so if you have a very big or wide tunnel or or in this case a pipe and water is running through that means if the the opening is really wide a lot of water can get to your sensor in this case but if that if you have that have the same amount of water in the pipe gets smaller with the same amount of water not as not as much waters ultimately gonna hit your sensor and as far as photography’s concerned that means not as much light is actually going to enter through the lens and actually at the sensor so if you use a more closed down or narrow aperture you’re gonna need more light to actually get a properly exposed photo we will do a future video explaining on what you can actually do in post-processing to increase exposure and how much you can kind of pull and play if you’re shooting in RAW in raw as opposed to shooting with JPEG but long story short you’re gonna need more light so if you’re in a situation where there’s too much light and you you need to you need to bring your exposure down then at that point you’ll have to narrow down your aperture let me also talk about just just so you guys know as well really the main difference between smaller and wider apertures the biggest thing is going to depth field I’d have to feel that smaller apertures is going to be greater while if you have a larger aperture the depth of fields can be more shallow but it’s in terms of light in the amount of life they’re gonna need if the if the larger if you have a larger aperture you won’t need as much light if you have a closed or narrow aperture you will need more light and that kind of allows you to kind of ebb and flow as far as how much depth of field you want but there’s there’s gonna be more changes to that as far as what are the best apertures for situations that you’re gonna commonly find yourself in if you’re shooting outside and you you want a lot of background blur set your aperture to the lowest or the max that you can for your lines if that’s F 1.8 F 1.8 will be the best one if you’re indoors it’s really low light and you’re just trying to get a properly exposed photo set your aperture again the 1.8 so you can let in as much light you’ll also get a little bit more shallow depth of field if you’re shooting landscapes and you want everything from the point of focus to the foreground the mid-ground and background and being focused at that point set your aperture to the greatest value that you can for this lens right here that’s gonna be f-22 for your lens and maybe f-18 it could be a little bit different if you want the sharpest photos possible what you have to do every single lens that’s manufactured has a kind of a bell curve as far as sharpness and every single lens that’s been manufactured also has a usually a 1 or 2 soft aperture where the lens is going to the sharpness for this lens right here typically F a 5.6 will be the sharpest for your lens it’s going to be in the middle the range will be the sharpest aperture if you want the sharpest photos granted that’s gonna kind of change your debt to field your depth if easily be kind of middle the road so you’re gonna have some some some a little bit of give in in terms of in front of this the subject being focused so have a little bit of give on the background being a little bit in focus so that’s something creatively kind of to make a make kind of a distinction between you might have to make a little bit of a compromise but if you want the sharpest photos that will give you the sharpest photos we can go we can go on and on with examples I will give you guys in a future video more specific examples and give you more situations so that you know but for the purposes right now will just give you those four so you at least have an idea what some of the best settings are depending on what you want but the thing you always have to ask yourself when it comes to considerations with changing aperture is some okay what kind of environment my what’s the light light do I have a lot of light do I not have a lot of light what kind of subject matter am i shooting am i moving am i shooting a subject that’s moving whether that be a car a person or just an object how fast is that person moving and how much depth of field do I want is it that I have everything in the photo be in focus these are kind of the considerations you have to ask when you’re when you’re starting to kind of dive into the ebbs and flows and the changes that are going to be needed when you’re when you’re starting to make settings and changes in aperture because every single setting that you change as far as changing like the opening or narrowing down it will impact the photo it won’t necessarily always change sharpness sometimes it will sometimes it won’t but it will change exposure every single time that you do that and the more narrow that that opening is yes you’ll get greater depth of field but at the same time you need a lot more light which is going to also change the way the photo looks and how and how much light that you’re gonna need to get it properly exposed photo so you know kind of in closing the biggest things when it comes to aperture is is that you have to really make considerations on okay what do I need to be in focus where’s my lens the sharpest what’s kind of the consider what’s kind of the creative effect that I’m going for what’s actually really important and what’s my subject matter how much light do I have as long as you know those kind of those those settings right there in those values you’ll be totally fine when it comes to to setting aperture to get the results that you really want that right there kind of wraps up today’s video we have a lot of other great content coming out to really help you guys to make sure you’re making sure that you understand the fundamentals so you don’t just get beaten down when you’re out there and you’re just you’re looking at the back your camera and you’re like man why is it so bright like oh my god I can’t get anything in focus because that was me for a really long time actually cuz I didn’t understand aperture among a lot of other settings that we’re gonna cover in future videos but you guys know what to do man if this is this is kind of we’re gonna wrap up just just how we’re talking about just this topic right here but we’ve got a lot of other great content to come definitely if you want more details and and more information on some of the other other other issues that the beginning photographers struggle with I know what I did right here you know what to do definitely check out the website check out some of the more in detail blogs that we have the subscribe button is right below right here you don’t hit that subscribe button and just you know while you’re down there just kind of mouse over a little bit and just hit that like button – and you’re welcome to leave we read absolutely every single comment we read every single email that you guys send us we’re excited to get feedback we’re excited to also know what kind of topics you guys would like us to cover until next time guys peace out

What exactly is Aperture? What’s the difference between Aperture & “F-Stop?”

“Aperture” in photography refers to the size of the opening of a lens. Generally, the term is used to describe the maximum size of the lens opening at its lowest achievable “F-Stop” setting. Beginning photographers confuse the term F-Stop with Aperture, so let’s take a moment to clarify that right now.

“F-Stop” refers to the current Aperture (size of the lens) selected.

Important note before reading on: F-Stop is notated as f/number.  f/1.8, f/2.0, f/2.8/, f/4.0, f/5.6, and so on.  Since this number is always a fraction, the greater the number, the smaller the opening of the lens at that current setting. We will discuss the more technical reasoning behind this in a future post. 

Think: Aperture = Maximum possible size and F-Stop = Current size. F-Stop ( i.e., f/1.8) is the actual Aperture setting while Aperture itself is typically the maximum setting a lens can achieve when fully open.

Take a 50mm 1.8f lens for example. f/1.8 refers to the maximum Aperture achievable for the lens at its widest setting. Now say we set the lens to a Aperture of f/4.0, this is now considered a specific F-Stop within the range of the lens. Both Aperture and F-Stop are referring to the size of the lens, but the sizes being referred to are different. It’s crucial that we make that distinction, as it often leads to confusion.

Note: Aperture is set directly on the lens itself for older generation manual focus only lenses. For autofocus lenses, it can be either set on the lens itself (if the lens has an Aperture ring) or in the camera. Only generation lenses didn’t have automated Aperture blades, so adjusting through the camera will not work.

What happens as Aperture changes?

As you change Aperture, what you’re actually changing is the overall size of the opening of the lens (the diaphragm). Adjusting Aperture directly changes how much light is entering through the lens to then reach the cameras sensor.

With a smaller Aperture, or higher f-stop, for example f/11 or f/22, the opening of the diaphragm in the lens is relatively small compared to the actual size of the lens. When the opening is smaller, less light reaches the sensor. Look at the opening of your lens as water traveling through a pipe. The smaller the pipe, the less water overall moves through. Light functions the same exact way.

Having a smaller Aperture does a couple of things.

One: if less light entering through the lens is hitting our sensor, more and more light is needed to achieve properly exposed photos since the opening is decreasing in size.

Two: as the Aperture narrows, light gets more and more focused which directly changes the Depth of Field of the photo and makes it larger. And as the Aperture decreases, the Depth of Field will only become larger and larger until it gets to a point where the entire photo becomes sharply in focus. (Confused or need more details on how Depth of Field works? See Blog Post: what is Depth of Field for more information) Each sequential decrease in Aperture setting, say from f/1/8 down to f/22, increases Depth of Field. Moving from f/small number to f/big number is referred to as “stopping down” a lens and each step will decrease the amount of light reaching the sensor but increases Depth of Field.

How wide or narrow the Aperture, directly influences how much light reaches the sensor and changes your Depth of Field.

What’s the difference between a small and large Aperture?

To summarize and simplify this as much as possible, think about it this way:

Smaller Aperture (large f-stop number in camera) = smaller hole which means more Depth of Field + more light needed

Larger Aperture (small f-stop number in camera) = larger hole which means less Depth of Field + less light needed

Larger Apertures cause more shallow backgrounds and more background blur. This helps you focus the viewer’s eye by selectively focusing on the elements or subjects you do want then blurring out the foreground or background elements that you don’t. While, Smaller Apertures are best to get all of the elements in a photo in focus and relatively sharp. While in the exact middle of the Aperture range of your specific lens is where you’ll achieve the sharpest photos possible with that lens. With the addition to some elements in the foreground and background also being in focus, but not all.

Note: All modern autofocus lenses have been manufactured this way, it’s a standard in the manufacturing process across all camera/lens brands. 

What’s the best Aperture?

The best Aperture to use is the Aperture that gets you any of the following: the amount of light you need to get a properly exposed photo, a certain Depth of Field, or a specific Shutter Speed you want. In some situations, you’ll be forced to shoot either more open or closed down depending primarily on one of two main factors:

Firstly, the lighting conditions in the environment your shooting in, and, secondly, what the subject is doing. Just know, selecting the best Aperture will always depend on what your goal is during that shoot. Here are some common situations you will eventually find yourself in along your journey and some insights I’ve found to best suit those situations throughout mine:

Is your goal to get a really shallow depth of field in the image and blur out the background? Then shoot at a more open Aperture.

Note: more open Apertures will directly affect how easy it is to focus. You will experience difficulty when shooting at wide open Apertures (f/2.8 and below) with both autofocus and manual focus lenses. And if you miss focus, the subject will be out of focus. Take care when focusing. 

Are you shooting during the day, where you have ample light and want everything in focus? Then shoot at a more narrow Aperture.

Are you shooting at night or in a low light environment where it’s very dimly lit and you need to just get a properly exposed photo? Then shoot at a more open Aperture.

Are you shooting a portrait in a studio setting with ample light and want the sharpest image possible? Then shoot at Apertures in the middle of the range of your lens.

Are you shooting action and  you need a faster Shutter Speed? Well, the fastest Shutter Speeds are available at  f/1.8 or below. Why? Because when you lens if fully wide open, it allows the most amount of light possible, which means you can have a faster Shutter Speed. So what if my lens doesn’t go to f/1.8? No problem, set your lens to the lowest value available. If that’s f/3.5 or f/4.0, then f/3.5 or f/4.0 will be the fastest.

We can go on and on with examples of what Aperture to shoot when and where, but the idea is always this: what is my goal? Below are some questions that will help you figure out what the purpose of the photo is and also help better assess your shooting environment to make the best decision for your specific situation. You can rest easy my friend, after that decision is made, setting Aperture becomes as easy as pressing a button. Thank god. Praise camera jesus, right? That you shall.

What am I shooting right now? What’s the main subject of the photo? Is the subject moving at all? Okay, how fast are they moving? Very fast, moderately fast, slow or are they completely stationary?

What kind of look do I want? Do i want everything to be in focus? Do I want only the subject in focus? What should be in focus here?

Am I shooting on a tripod? No, can I position myself so I can support the angle I’m shooting to make it more stable? No, how important is it for me to freeze the action going on in the photo?

How important are elements in the foreground and background in telling the story and giving context to the image? Does the background or foreground even matter?

Just some thoughts to get you thinking about the different factors that may or may not be important to your specific situation.

When should you adjust Aperture? 

Adjust Aperture when any of the following happen: when the light in your environment changes which then causes your exposure to change and you can’t change either shutter speed or ISO to get a properly exposed photo.

When you’re not in this situation, however, and Depth of Field is important to what you’re shooting, just change the Shutter Speed or ISO to compensate for those changes in light. But, just know, if you’re ever in that one off rare situation where you can’t change either of those AND there’s no way for you to increase the available light (either by changing the direction your shooting, adding artificial light, or moving environments) you’ll be stuck having to change Aperture. Which isn’t really the end of the world, but it will DEFINITELY affect your photo. Outside of those kinds of situations, you won’t really need to change aperture, unless you want to.

Considerations with Aperture

Changes in Aperture DO NOT affect either Shutter Speed or ISO! Whatsoever. Changes in Aperture WILL affect Exposure and Depth of Field. Closing down the Aperture will cause the exposure to decrease, but also increases Depth of Field. Opening up the Aperture Has the opposite effect, decreasing the Depth of Field. We can use Shutter Speed and ISO to change exposure, but they also cause other changes to the image themselves outside of just shifts in exposure. See Blog Post 2: ISO and blog post xx: Shutter Speed for more details. 

Smaller Aperture = Lower Exposure + Greater Depth of FIeld

Larger Aperture = Greater Exposure + Smaller Depth of Field

There’s an interesting relationship between Aperture, Shutter Speed and ISO. Changes to any of these three settings directly affects exposure based on whether the setting was increased in value (causing a decrease in exposure for Aperture and Shutter Speed) or was decreased in value (causing a decrease in exposure for ISO). But, here’s the thing, these settings not only just change exposure. Our other blog posts on these topics will explain what those changes are in greater detail.  What you really need to know in this specific post is that photography is a game of balancing, and everytime you change one setting your directly affecting another.

This simply fact is arguable one of the greatest challenges from beginning photographers. It’s going to take practice and experience to figure out what settings work for you. Only practice and experience will teach you the skills needed to master your specific shooting style. Not to mention, each of us has a unique way we approach photography to begin with, and with practice you too will figure out what settings you prefer in the situations you find yourself shooting the most. We can talk about thousands of examples, but every environment and situation is going to call for differences and the way we all shoot changes the decisions we make. We encourage you to read the in depth articles on the fundamentals of each of these settings, and the best practices to see how they affect an image. But, experience is the key here.

Here are some closing tips though: 

Think of Aperture as the pipe analogy I mentioned before. Smaller pipes mean you’ll need more water, but can also mean the water is more concentrated, concentration in this example meaning a greater Depth of Field.  While a larger pipe means you’ll need less water, but also means the water will be less concentrated and more shallow.  I struggled with understanding this example for 15 months straight. It wasn’t until this past spring that it made sense and I started to understand how to control light. You knowing and learning that from the earlier stages of your journey will make your understanding of photography far greater than where I first started.

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About Devaun Lennox

Is an upcoming fashion and editorial photographer based in Las Vegas, NV. Launching into the scene in early 2017 and shooting, on average, 20 of the top local talents and faces monthly since then, he’s been able to...