Understanding Aperture Part II

Utilizing aperture in your photography is a great way to add an artistic touch to your images. Through the use of adjustments in depth of field, lighting and lens flares, a photographer can create imagery that is both compelling and thoughtful, showing an advanced use of lens and camera tools that go beyond a basic point and shoot. In my last post, I introduced aperture, what it means and how to use it to affect the artistic nature of your photography. In part two, we’ll discuss some specific tactics and photo styles to help you to get the most out of your aperture. Some of the most common photo styles that are heavily influenced by a carefully selected aperture are portrait photography, landscapes, and night photography. I’ll also give a quick tutorial on using your aperture to capture aesthetic sunbursts in your landscapes. Let’s get started.

Portrait Photography
The use of aperture is perhaps most prevalent in detailed portrait photography. This includes photos of people, animals and isolated subjects. While I am by no means an expert on high level macro photography, the principles are the same (focusing on utilizing a shallow depth of field to isolate a subject), so macro will be included here as well.

This bighorn sheep was captured at 600mm at f/8 to ensure that the entire body was in focus while still keeping separation between the subject and background and producing a nice blurred background bokeh. Photo Credit: Chris Gheen.

When shooting portraits, the goal is to isolate the subject. As a photographer it is key to eliminate any distractions in the foreground or background that could potentially draw the viewer’s eye to another portion of the frame. Using aperture as a way to highlight your subject is a great way to show intentionality in your portraiture. By selecting a wide aperture (low f/ number) the photographer ensures a shallow depth of field, which will help to reduce the clarity of background and foreground distractions. The classic high level portrait photos with that oh so softly blurred background is what sets photographers apart from John Q. Tourist with the newest iPhone. And by using a fast lens, the photographer is able to increase the bokeh in the background to really add to the artistic quality of the photo. Think of it as a way to highlight both your subject, and your equipment. A delicate bokeh behind a tack sharp subject not only isolates the subject, but also provides contrast between the sharp and the soft that we discussed in my recent post about composition.

When shooting portraits, it is crucial to get the subject’s eye in focus. If your subject doesn’t have an eye (examples include flowers or other macro scenes), focus on the point that you want the viewer to connect with the most. By capturing the eye in focus, the viewer is naturally drawn to the subject, making the human connection possible with an inanimate photograph. The next step after getting the eye in focus is to ensure a reasonable amount of the subject is still in focus. Depending on the scene, this may be the entire subject, or just the face, or maybe even only the eye. A common mistake I’ve seen in portrait photography is that oftentimes a photographer will select too wide of an aperture, which makes the depth of field too shallow. This can result in portions of the subject being out of focus and can detract from the overall sharpness of the photo. Be extra careful of this when using long lenses, as depth of field is exaggerated at longer focal lengths.

Landscape Photography
In landscape photography, often times the goal is to ensure clear, in focus exposure from front to back in your frame. This means having to increase your aperture value enough to get a clear shot, while avoiding the diffraction that occurs at higher apertures.

This image, captured at f/11 to ensure crispness all the way to the back of the image and optimal clarity throughout. Photo Credit: Chris Gheen.

For this, in 90% of exposures, I recommend shooting at f/11. By shooting at f/11, you’re going to ensure enough of your exposure is in focus to provide a sound landscape focus profile, without getting diffraction that occurs at higher apertures. Diffraction is what happens when you force light through a very small opening (typically above about f/20 depending on the lens) and the light is forced to bend as it moves through that opening, and it can cause softening of your images. There are times when this diffraction is not big enough of a concern to worry about, and we’ll discuss those later in this post. But the important thing to remember here is that for optimum clarity in your landscape images, opt for aperture values between f/9 and f/16, depending on light and other settings in your image and how long your focal length is.

If you plan on utilizing focus stacking, however, understand that there is a “sweet spot” on every lens where it is its most crisp. Sometimes that can be a very low aperture, and you’ll be better off shooting at that lower setting and stacking your images. See Matt’s post on focus stacking to learn more about this brilliant technique that will help you gain maximum clarity all the way through your image even when shooting at low apertures.

Night Photography
When shooting nights, there are a ton of different factors that come into play. Whether you’re at home shooting star trails, in the desert chasing the milky way, or on one of our Ultimate Northern Lights tours, it’s important to know that your aperture will play a huge part in how crisp your stars will be, and how long you’ll need to keep your shutter open. To start, when not shooting star trails, opt for a very wide aperture.

This image, captured at f/4 and 15 second exposure allows for greater light transmission and the ability to capture more stars in a shorter amount of time to limit the blur as the stars move across the sky. Photo Credit: Chris Gheen

This will ensure you can maximize the amount of light getting through your lens, and also minimize the amount of time necessary to keep the shutter open in order to capture the stars. This is great for getting compelling foreground shots under a starry sky, or for photographing the milky way, as the less time the shutter is open, the less blurring you’ll get in your stars. However, know that the lower your aperture value, the more your stars will appear to move as you keep the shutter open, and as a result, the shorter your shutter speed must be to really freeze the stars in your image. By shooting through a narrower (higher number) aperture, you will actually be able to keep your shutter open longer as the camera will be viewing the stars through a smaller opening, and as such, they will appear to move less relative to the sensor. It sounds complex, but know that this really only makes a difference once you start adding in things like motorized star tracking tripod heads and other fancy toys like that. You’ll be able to achieve incredibly crisp and bright stars with very long shutter speeds at lower apertures as you increase the camera’s depth of field and capture more of the stars in the distance. I’ll be writing a full post on night photography in the coming weeks where we’ll discuss how to use aperture, shutter speed and a variety of tools and tricks to maximize your astrophotography.

Sunburst Photography
One of the coolest tricks to know about using your aperture is the use of sunbursts. These are the star shaped light patterns around the sun that you see in a lot of landscape photos taken where the sun is in the frame.

This sunburst panorama from Bryce Canyon was shot at f/22 to ensure maximum crispness in the lines surrounding the sun as a way to introduce a more compelling composition component to the image. Photo Credit: Chris Gheen.

The sunburst is an effect that occurs as you shrink down your aperture opening (large f/ numbers) and cause the light to force its way through the small opening. There will be naturally occuring gaps in your lens’ aperture blades where faint amounts of light are able to squeeze through when pointing your lens directly at a bright light source. These gaps cause the flaring that occurs when shooting at the sun, as well as the flares that occur when shooting street lights or other bright artificial light sources. This can actually be used to your advantage when shooting landscapes as it adds a very compelling component to your imagery, and can actually give you additional options for shots long after sunrise. The sun does not need to be at the horizon, or even close, in order to grab a quality sun star. Just line up your subject, crank your aperture to f/18 or higher (I usually go for f/22 to really get crisp lines around the sun), make adjustments for your shutter speed and ISO to ensure correct exposure of your subject, and fire away. It is important to note that your camera’s evaluative metering will show that your scene is over exposed, so I’ll often spot meter to my subject when attempting a sunburst, to make sure that my foreground isn’t too dark and shoot in manual rather than aperture priority so that my camera isn’t over compensating for the sun being an overly bright portion of the image (spoiler alert: the sun will be bright no matter what). Another thing to keep in mind is that the effect will be roughly the same at 1/1000 second exposure as it will at 1/30 second exposure, so don’t worry about losing your sunburst at lower shutter speeds. One more note about sunbursts is that the shape and definition of the light pattern is specific to the lens. Each lens has slightly different aperture blade shapes and as a result will give you a slightly different sunburst pattern as you change your aperture. There are actually a few high end lenses now that have a cult like following specifically for the clarity and definition of their sunburst capabilities.

Overall, I’ve found that most folks on our tours are often more intimidated by aperture than by any other component of the exposure triangle. It really is not necessary and can be a great tool to add to your photography tool box to help you get the most out of your images. There can be a ton of variety in the artistic nature of your images just by adjusting your aperture a few clicks one way or another. The most compelling images I’ve seen from our guests are often ones where folks just tried something new to experiment with their camera’s settings and came out with something great. That’s the beauty of digital. I’ve told countless guests on our tours that digital film is cheap. Try something new. Experiment with different settings and play with your camera, and it may surprise you by just what you can accomplish. Until next time, get out, see what you can come up with by modifying that aperture, but be intentional and I’m sure you’ll surprise yourself with a few new techniques. Happy shooting!

Chris Gheen








Chris grew up exploring the mountains of North Carolina, originally with his family on weekend camping trips and later as a self taught rock climber and backpacker, leading him ultimately to a degree in Recreation Management from Appalachian State University with a focus in Outdoor Experiential Education. Immediately after graduating, Chris drove west, knowing the mountains and opportunities for adventure were much bigger. Since then, he has worked in a variety of guiding applications, from small leadership non-profits, to adolescent wilderness therapy, to commercial hiking and tourism guiding in California, Arizona, Utah, Colorado, Wyoming and Montana, always with a camera in hand. Chris loves teaching and sharing his passions and experience with others and is sure to provide careful insight and education whenever the opportunity arises. Chris currently resides in Bozeman, Montana where easy access to Yellowstone National Park allows him frequent trips into the park to photograph wildlife and the unique geologic features of the area. When not behind the lens, he spends his time backcountry skiing, ice climbing, and mountain biking, always on the lookout for a new unique perspective to photograph. The mountains have always been a point of inspiration for Chris and he is excited to capture the beauty of the natural world in an effort to share the space he is so privileged to work in with those around him. For a look at some of Chris’ work, visit his website www.chrisgheenphoto.com


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