Today we are going to talk about one of my favorite subjects…aperture. Yeah maybe that makes me weird or geeky, but I'm owning it. I love aperture!

I guess this is kind of how I see the world. It creates layers of focus that lets you guide the viewer's eye through the photograph. It allows an artistic expression of how you portray your scene, subject, vision.

OK, so what is it exactly? How does it do all of this magic? Let's talk about that.

WHAT IS IT:

Aperture is actually the size of the opening in your lens that lets light through to your camera sensor - similar to the pupil in your eye. When the opening is really big, then the number, referred to as f-stop, is small. So f1.4, for example, is a really large hole in your lens, allowing a lot of light in. f22, on the other hand, is a really small hole and lets very little light in.

I know, I know. This all gets really confusing really quickly. But if you stick with me now, and then again when we talk about it later (oh and we will) eventually it will start to make sense.

HOW DOES IT AFFECT MY PHOTOS?

Aperture affects the depth of field of your photo. This refers to how much of the image is actually in sharp focus. A shallow depth of field means only a portion of the image is in focus, where a deeper depth of field means most or all of the image is sharply focused.

Now, the shallow depth of field - only a portion of the image is in focus - is achieved through a SMALL f-stop number like f1.4, f2.8 or even f4. Those numbers mean big hole, shallow depth of field. A face might be in focus, and everything else is blurred. Here's an example of that…

The benefit of shallow depth of field? Well, it's an artist method for one thing - to create a specific effect. And it also really emphasizes your subject, bringing the viewer's eye right there before wandering elsewhere.

The blurred background of a shallow depth of field image is referred to as bokeh. This is a Japanese term that describes the aesthetic quality of the blur. Yep, that's right, even blur can be beautiful. Depending on the lighting and your lens, some bokeh takes on a circular quality, some more "swirly". It's a whole other rabbit hole we could go down. Some lens reviews talk about bokeh quality as a feature of the lens. So let's move on before we get stuck here.

A deep depth of field, on the other hand, allows most or all of the scene to be in sharp focus. This works well with landscapes for example, like this one…

SOME FACTORS TO CONSIDER:

Let's say you are shooting in Aperture Priority mode. To me, that is the BEST way to really learn aperture. You put your camera on the A (or Av) setting and then YOU choose the aperture, and your camera chooses everything else. Sounds easy, right?

It is…but there are a couple of things you still need to consider.

Let's recap:

A small f-stop number like f2.8 = a large hole in your lens = lots of light coming into your camera

A large f-stop number like f22 = a small hole in your lens = little light coming into your camera

Why is this important? Well, if you are off somewhere and see a beautiful scene, and think "I want ALL of this to be in focus, I'm selecting f22." That would be fine on a bright sunny day. BUT if it's getting to be dusk, or a cloudy day and it's not pretty bright out…there could be some issues.

When I say issues, here's what I mean. IF you choose f22 and the light is fairly low (cloudy day, sun going down), then your camera will need to compensate for the low light coming into that little hole by changing your shutter speed. It will change your shutter speed by making it slower, therefore allowing MORE light to come in.

That can be okay UNLESS the shutter speed slows down too far, which can result in focus problems. If the shutter speed is 1/60, 1/50, 1/30…it becomes difficult to hold your camera still enough to make sure your image is sharp. It really depends on you and how steady you can hold your camera. But if it's getting into the 1/40th range, you will likely see some blurry photos.

What the heck do you do about that?? Well, it could be as simple as changing your aperture a bit. Sure f22 sounds nice, but let's bump it down to f16, f11, even f8. You'll still get a pretty evenly focused image, but you'll let more light into the camera. And that makes your camera happy.

There are some other things you can do, like increase the ISO. We don't want to go too far down that rabbit hole either - this is a blog post, not a novel.

In order to get all of the buildings, and the background in focus, this Peru photo was shot using f22.

To emphasize the sculpture, while still having the architecture in the background, this Paris photo was shot using f4.

LET'S SUMMARIZE:

Aperture adjusts the size of the hole in your lens.

It allows you to adjust depth of field.

Choosing a small f-stop number (large hole) like f2.8 or f4 will result in a shallow depth of field with a focused subject and blurry (bokeh) background.

Choosing a large f-stop number (small hole) like f18 or s22 will result in a deep depth of field and sharply focused scene.

WHEW! I know, I get it. It's a lot and it can scramble the brain. To help all of this make more sense, I created the Camera Settings Cheat Sheet, which you can download here. It summarizes all of this (and more) in a handy pdf.

Here's my recommendation for how to get this information overload to become an aha moment. Get our your camera, set it to aperture priority (likely A or Av on your top dial). Now go out - doesn't matter where - and make photos in f4. All day. Or for an hour. Or all weekend. Whatever you are willing to do. NOW set it to f22 and make photos all day. Or for an hour. Or all weekend…you get the picture. (hee hee, literally)

I would even say to pick a week and every day make photos in a different aperture. Or pick a day and every hour change the aperture. I think you get it. It only makes sense by doing it. Over and over.

Don't worry about the outcome, this is just practice. Just play. Kids learn from play and so do we. It's a scientific fact. So listen to science, get our your camera, and play with aperture. And you know the drill…post your results to our Facebook group. I can't wait to see you there!

Aperture 101

Ready to create photos you LOVE?