The Basics of Photography - Aperture
Photo by Wan San Yip on Unsplash
Aperture. If you’re new to photography, you may be hearing different terms thrown about loosely. Aperture, shutter speed, ISO, f/ stop. What do they all mean? In this article, I’m just going to cover aperture, and I will cover the other topics in separate articles.
What is aperture?
Aperture is the first of three sides of what’s called the exposure triangle. The other two being ISO and Shutter Speed. In the most basic of explanations, aperture is referring to the hole in your camera lens that lets in light. That’s it. Of course there is more to it than that, but at the most basic level that’s all it is. A lot of beginners get tripped up when discussing aperture primarily because of how the f/ stop concept works. Let me explain. Every camera lens has a maximum aperture and a minimum aperture which indicates how large or small the hole in the camera lens can get. These sizes are indicated by what is called the f/ stop. Here is where beginners get confused. On a lens, the smaller the f/ stop number (e.g. 1.8 or 2.8), the larger the hole in the lens gets, therefore letting in more light. Of course the opposite applies as well. The larger the f/ stop number (e.g. 11, or 16), the smaller the hole in the lens is, therefore letting in less light. You may often hear photographers refer to lenses with a wide aperture (larger opening) as a “fast lens”. This simply means that the lens is able to open up the aperture really wide (small f/ stop number) and let in a lot of light. You will commonly hear these terms in sports photography as indoor photography generally requires a fast lens due to poorer lighting conditions.
The upsides and downsides to aperture
As with most things in life, there is a downside to this concept, or it could be an upside depending on your situation. When you open the aperture up wide (smaller f/ stop number), you are sacrificing the amount of things that you will have in focus. For example, a lot of portrait photographers will shoot at an aperture of 1.8 or 2.8, which is a wide aperture. This wide aperture creates a shallow depth of field, meaning you will get a blurry background behind the subject but if the depth of field is too shallow, then you could have out of focus subjects if they are behind one another. If you are shooting a single subject, this usually isn’t an issue as they are all you need in focus. The problem starts to develop if you are shooting multiple individuals or groups of people, especially if they are at varying distances from the camera lens.
To combat this problem, you would increase your f/ stop (make the hole smaller, larger number) which will increase the depth of field, allowing more things to be in focus. Again, the downside to doing this is you must now compensate another way since you are reducing the amount of light that the lens is letting in. You compensate by increasing the ISO or lowering the shutter speed to let in more light. But those topics will be discussed in a different article.
Which f/ stop should I use?
The f/ stop that you choose will be entirely dependent on your shooting situation and the lens you are using as well as what creative look you are trying to achieve. If you are shooting landscape photography or anything where you want everything in focus with minimal blur, you will want to increase your f/ stop number (smaller hole). This will let in less light, but will ensure that more things are in focus. On the opposite side of the spectrum, if you are someone who is shooting portraits, indoor sports, or anything where you want a blurry background behind your subject (bokeh), then you will likely want to shoot at a wider aperture, such as f/1.8, f/2.8, or an f/ stop in that range. This will let in more light, but will blur the background and create a much shallower depth of field.
Something that you should keep in mind is that not all lenses are the same, and not all lenses can open up wide to f/1.8 or even f/2.8, and not all lenses will close down all the way to f/16. It’s important to check the lens specifications before purchasing to determine the minimum and maximum aperture. The lens aperture ranges are generally listed on the lens itself around the glass. I will go more in depth into this subject in another article!