Understanding Aperture

Understanding Aperture

Aper­ture is defined as “a hole or an open­ing through which light trav­els”. Under­stand­ing aper­ture is key in help­ing you take bet­ter pho­tographs and in under­stand­ing the expo­sure tri­an­gle. Under­stand­ing aper­ture will also help you get that fab­u­lous blur­ry back­ground that many pho­tog­ra­phers strive for, or that crisp, clear land­scape shot you may be look­ing for. 

If you think about your cam­era in terms of an eye, the aper­ture is like the pupil. Aper­ture is the hole in which light enters the cam­era. The lens will deter­mine the aper­ture range you can shoot, not your cam­era. Remem­ber not every lens has the same capabilites. 

Aperture & Fstop

Aper­ture and Fstop are essen­tial­ly the same things. You may hear some­one say, “what was your aper­ture?” or “what was your Fstop?”. They are ask­ing the same ques­tion. As I men­tioned, your cam­era lens deter­mines the aper­ture that you can achieve, which is also known as f‑stop, and you will see num­bers writ­ten on your lens such as “f1.2” or f “4–5.5. This is the aper­ture range of your lens.

The low­er the num­ber, the big­ger the hole, the more light that comes in, result­ing in only a small por­tion of your pho­to being in focus. This helps you achieve those pic­tures with a blur­ry back­ground. Shoot­ing a larg­er aperture—F1.8–2.5 means more light will come into the cam­era, and there will be less focus in your photo. 

The high­er the num­ber the small­er the hole, the less light that comes in, result­ing in a larg­er por­tion of your pho­tog being in focus. This helps you achieve a pho­to where the whole image is crisp and clear. Shoot­ing a low­er aper­ture-F16-22 means less light will come in and more focus. Low­er aper­tures are great for land­scape shots. 

This is often con­fus­ing to pho­tog­ra­phers just start­ing out in man­u­al. You just want to keep in mind that the small­er the num­ber, the big­ger the hole, and the larg­er the num­ber, the small­er the hole. It’s back­wards to what makes sense and this is what trips many begin­ners up. 

What aperture to use when?

I say it all of the time to my students…I tru­ly believe that aper­ture is where pho­to­graph­ic mag­ic hap­pens. It adds dimen­sion and light to your pho­to­graph, and I feel it also helps take a snap­shot to a more pro­fes­sion­al look­ing photo. 

So, when do I use what aper­ture you may ask? I tend to set my aper­ture based on what I am shoot­ing. If I am shoot­ing one sub­ject, such as below, and want that beau­ti­ful, but­tery blur behind the sub­ject, I will shoot wide open, mean­ing an f1.8‑f2.5. I focus on the sub­ject that I want to be clear and in focus, I make sure there is a bit of dis­tance between my sub­ject and the back­ground, and the lens cre­ates that soft but­tery background. 

I shoot at a more nar­row aper­ture when I shoot land­scapes and want every­thing to be crisp and clear. Or if I am on vaca­tion and I want every detail of a build­ing or mon­u­ment to be in focus, like in the shot below. A nar­row aper­ture is per­fect for pho­tograph­ing a larg­er group of people. 

I hope that this helps clar­i­fy aper­ture a bit and that I’ve helped you under­stand things a bit more clear­ly. Now I want you to grab that cam­era, find a sub­ject, and work on cre­at­ing your own amaz­ing back­grounds. Shoot wide open to get that blur and nar­row down to get more clar­i­ty in your pho­to. And if you want to learn even more about the expo­sure tri­an­gle, make sure to check out The Begin­ners Pho­tog­ra­phy Essen­tials Course.