How to Control Aperture and Create Images You Love

1 aperture
Controlling the aperture is one of the most powerful ways to improve
your images. It’s also the topic that continues to perplex photography
students everywhere. Rather than unnecessarily complicating matters, I
prefer to demystify the subject. In this tutorial, I’ll reveal how both a
wide and small aperture can be used to create consistent and beautiful
results.

Consider the Background

 

2 butterfly
When I’m about to take a photo, the first question I ask myself is,
“What kind of background would be best?” With wildlife, sports,
portraits, and still-life objects, I often want the subject sharp, and the background to be a soft blur.
As you’ll see in the example above, the blurred background allows the
viewer to focus on the beautiful details of the butterfly, not on the
leaves behind it. To do this, I chose a wide aperture by adjusting to a
smaller f-number. At f/5.6 the opening in your lens is physically wide
open, creating what’s known as shallow depth of field.
3 puffin
In the example above, I photographed an Atlantic Puffin at f/5.6. The
bird is tack sharp while the foliage in the distance is very soft. The
theme of the photo is clearly about its colorful beak, and there is
little else in the photo to detract from it. For this reason, wildlife
photographers typically use wide apertures for the majority of their
work. To further emphasize the effect, try positioning yourself so there
is distance between the subject and the background.

Freezing Action

 

4 soccer
If you flip through the pages of Sports Illustrated, you’ll notice
how most of the players are sharp while the fans are out of focus. The
wide aperture chosen by the photographer not only creates that shallow
depth of field, but it also lets a great deal of light into the camera.
As such, it’s possible to use a fast shutter speed to freeze the action.
If you are serious about sports photography,
a lens that opens all the way to f/2.8 is worth the investment. You may
even hear people refer to them as “fast lenses” which describes the
speed in which the wide aperture lets light into the camera.

Focus on What’s Important

Before going any further, allow me to spend a moment on focus. When
using a wide aperture, be sure to place your active focus points on the
subject you want sharpest. These two vineyard photographs were both
taken with the same wide aperture of f/1.8, but they look very
different. This is due to my placement of the focus point indicated here
by the arrows. For the image on top, I focused on the vines closest to
me. As a result, everything behind it is soft. For the image on the
bottom, I focused on the distant vines. The shallow depth of field then
works to blur everything in front of the focus point.
5 focus example
We can see how all of this comes together in the image of the male
buck. I saw the large deer in October just after sunrise. With my active
focus point on his face, I knew the deer would be sharp. A wide
aperture of f/5.6 created a shallow depth of field. Not only was the
background blurred, but the tall reeds in the foreground as well. The
perspective makes it seem as if we’re spying on the creature through the
tall grasses.
6 buck
As you can see, a wide aperture
can help you create images that surpass routine snapshots. With this
new knowledge, you’ll start to recognize the techniques other
photographers have used in their photographs. Begin practicing with wide
apertures and you’ll soon be changing settings like a pro. Now, let’s
turn our attention to small apertures.

Small Apertures

 

7 castle
There’s a common misconception amongst photography students who
believe sharp photos are solely result of fast shutter speeds. While
that is part of the equation, the other equally important consideration
is the aperture. By achieving greater depth of field, it’s possible to
keep the entire subject in focus. In this second portion of our aperture
tutorial, I’m going to share the specific f-stops and techniques used
to create tack sharp images.
8 aperture opening
Don’t let the terminology trick you. The term “small aperture” refers to the physical size of the lens opening.
This may seem counterintuitive since the actual f-number is larger.
Yet, f/22 is a smaller aperture than f/16 because the aperture blades
inside the lens don’t open as wide. See the example above.
9 empire state
When you hear photographers say they are “stopping down”,
it means they are using a narrower aperture opening, for example going
from f/8 to f/11, or from f/11 to f/16. This renders everything sharp
from near-to-far, hence the phrase “great depth of field”. I’ve created a
phrase to help you remember this. “The greater the f-stop number, the
greater the depth of field.”
10 brooklyn bridge
Great depth of field is also useful when you’re photographing flowers
or close-up objects. If the aperture is too wide like f/2.8, only a
handful of the petals will be sharp. The solution doesn’t necessarily
have to be f/22 which is more suitable for a vast landscape; a better
compromise would be f/8 which provides enough depth of field for most
macro opportunities. Then, by simply focusing on the center of the
flower, the entire subject remains reasonably sharp.
11 dahlia
In a big sweeping landscape, it can be tricky to determine where to
focus. For me, apps that calculate precisely where to focus are just not
practical (or fun). To further emphasize the effect of the small
aperture, I have found a simple solution that really works. Place your
focus point on an object that’s 1/3rd of the way up from the bottom of
the frame and use a small aperture like f/22. Not only will the object
in the bottom third be sharp, but so will everything in front of, and
behind it. As an example, I focused on the large boulder towards the
bottom of the frame in this photo from Yosemite National Park.
12 yosemite

 

Where the Tripod Comes In

While f/22 may be an ideal setting for a landscape, it does present
photographers with a challenge especially in low light situations. Since
a small aperture doesn’t let much light into the narrow opening of the
lens, a slower shutter speed and/or higher ISO become necessary to
achieve a good exposure. These longer exposure times are the primary
reason most landscape photographers use tripods.
13 central park

 

Bonus Tip

If carrying a tripod is not possible, you can create a makeshift
camera support by placing the camera on a bag, a wall, even the ground.
Then, to avoid jostling the camera during the exposure, set the two
second timer to automatically trip the shutter.

14 jefferson

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