What is Camera Aperture? Dhavalilama’s Photography Basics
When it comes to mastering the art of photography, it is always important to first understand the basics. One of the most important of these basic concepts is camera aperture .
No matter how novice, or experienced you may be, a strong foundation of photography basics can really make a difference in how your photos turn out.
What is Camera Aperture?
Let’s start with the real basics on aperture—more specifically, what exactly is aperture?
Aperture refers to the opening on your lens’ diaphragm. This is what lets light pass through the lens.
What is Camera Aperture?
You know what aperture is now, but how does it relate to your camera? You will see that aperture on your camera is calibrated in what are known as f/stops.
The lower the f/stop the more exposure. These lower f/stops represent larger aperture while higher f/stops represent lower aperture.
So, a f/16 stop has a small opening that lets light in, while an f/1.4 has a larger opening that lets more light in.
Aperture is Controlled By What Mechanism?
Now you are ready to start controlling and manipulating the aperture on your camera. When you change the aperture on your camera setting, you are simply manipulating that diaphragm on the front of your lens.
Think of the mechanism that controls your aperture similar to the iris in your eye. It contracts and expands depending on how much light needs to get in there. The aperture refers to the diameter of this “iris” on your camera.
Aperture’s Role in Photography
Chances are, if you have been reading different photography tips and suggestions, you have been hearing a great deal about aperture. But what is aperture’s role in photography?
Aperture Affects Exposure
One of the main goals you will have when manipulating your aperture is to impact the exposure on your photos. However, it isn’t as simple as changing the aperture to change the exposure—aperture is actually a component in three main elements that make up exposure, also known as the exposure triangle.
They are aperture (of course), ISO and shutter speed. Whenever you manipulate the aperture you are also impacting the other ISO and the shutter speed. You can’t get proper exposure without proper aperture settings, but make sure that you look to ISO (image noise) and shutter speed (motion blur) when changing your aperture.
Aperture Affects Depth of Field
Another one of the ways that your aperture will impact your final photo has to do with depth of field.
The depth of field is the zone of sharpness in front of and behind the subject on which the lens is focused.
So, your depth of field is how sharp or blurry the area behind your subject is.
If you want a blurry background, and one that lets your foreground image really pop, then you want a lower f/stop or a large opening in the lens. This gives you less depth of field and that blurred background look.
If you want a sharp background, then you want a higher f/stop, or a smaller opening in the lens. This gives you more depth of field, and keeps the background just as sharp as the main image you are focusing on.
What is the F-Stop or F-Number?
We’ve already mentioned that those f/numbers or f/stops on your camera are responsible for regulating the amount of light that can go through a lens. The ‘f’ before the number actually means focal length.
The numbering system can be confusing to understand and why a higher number means a smaller opening instead of vice-a-versa.
Well it actually all has to do with math.
So, f=focal length. If the focal length of the camera is 100 mm, and the number after the “/” is 2, this is what the equation would look like.
25 is the diameter size, in millimeters of the physical opening of the lens where the light is passing through.
Now, let’s reverse some of those numbers.
So 50 (the focal length)/25 (the diameter) = 2. This is where you get numbers like f/2. But if that 50 mm lens is at f/22, instead of f/2, you are going to have a 2.27 mm opening—this is much smaller than the 25 mm opening at f/2.
So, with all of these math equations together, this is why you will see small numbers for larger openings.
Large or Small Aperture?
When deciding whether to use a small or large aperture, you also need to keep shutter speed in mind. The best way to think about this is to imagine the aperture opening is like an hour glass. The size of the opening in the hour glass will dictate how long it takes for the sand to pass from one side to the next.
So, the smaller the aperture the longer your shutter speed will need to be—you will need more time to accommodate the smaller opening.
When to Use Different Camera Apertures
Now that you have all of the math equations down, it is time to put all of your camera aperture knowledge to use. But first, let’s start with a basic guide on the different times to use different apertures. While every camera, situation and setting is different, these are all great places to start when trying out your new aperture know-how.
When you shoot landscape photos, you want the entire image to be crystal-clear. This isn’t a situation where you are honing in on a subject and want the majority of your background to be blurry or out of focus.
This is why you need a large f/number and a small opening. This will give you a deeper depth of field and make sure that the entire photo has the sharpest results possible.
F/16- Shooting Towards the Sun
If you are shooting towards the sun, such as situations where you may be shooting at noontime, then there is a way to manipulate your aperture to prevent the image from being overwhelmed by the sun. Most photographers dread shooting out in the bright sun, but you just need to remember the “Sunny 16 Rule.”
If you are ever in a situation where the bright sunlight is too much to handle and your subjects are getting raccoon eyes or you are dealing with harsh shadows, just change your aperture to f/16 and tweak from there.
You will also want to manipulate your ISO and shutter speeds (raise your shutter to get rid of ambient light and lower to let more ambient light in).
F/8 Groups of People
If you are shooting groups of people, where you want everyone in focus on people on the street or on the go—then you want to start at f/8. In fact, f/8 is a great setting to have locked and loaded on your camera if you are carrying it around and ready to shoot at any moment.
It is a great “central” or “neutral” setting that works in a number of situations. So, if you have your camera with you to capture a fun brunch out with friends or whatever comes your way, keeping it at f/8 so you are ready to point and click and get a great image is always a smart move.
Using f/4 for portraits is a great way to create a shallow, but not too shallow of a depth of field. If you want a nice, clean, crystal clear detailing of your subject’s face, without all of that background noise getting in your way—this is a great camera aperture for you.
You of course, can move your settings down lower, even to 2.8 if you want to, but give f/4 a try first—it will typically deliver a much better result for portraits.
Aperture is really important in astrophotography or space photography. If you want to take images of the sky, such as the star constellations, you will need to allow much more light into the camera to illuminate the sensor and allow enough light in to make the stars really pop.
With the right aperture you can let enough light in to make it easier to see stars you would not be able to see alone with just your naked eye. This is also a great f/stop to start at because you will likely be shooting on a tripod with longer exposure duration.
F/1.4 Northern Lights Photography
I’ve talked in the past about the difficulties that can come with shooting the Northern Lights. However, if you know what you are doing and are willing to put in the extra time—it can totally be worth it with northern light photography.
I recommend starting with the f/1.4 exposure, one of the lowest numbers allowing the most amount of light in. This is one of the only ways to really be able to capture the colorful natural wonder of the Norther Lights.
Now that you have a better grasp on camera aperture, what it means and how it impacts your photos—you can knowledge to better your photography skills and take your images to the next level.