Mastering Bokeh: Creating Beautifully Blurred Backgrounds

Introduction

Have you ever marveled at those stunning portraits where the subject stands out sharply against a dreamy, out-of-focus background? That magical effect is called bokeh, and it’s a hallmark of professional photography. In this article, we’ll demystify bokeh, explore its creative possibilities, and reveal how to achieve it in your own photos.

What is Bokeh?

Bokeh (pronounced “bo-kay”) originates from the Japanese word meaning “blur” or “haze.” It refers to the aesthetic quality of the out-of-focus areas in an image. Bokeh is all about depth of field—the range of distances within which objects appear acceptably sharp. Let’s break it down:

• Narrow Depth of Field: When only a small part of the image is in focus (like the subject’s face), we say it has a narrow depth of field. This is ideal for portraits, as it isolates the subject from distractions.
• Deep Depth of Field: Conversely, when most of the image is sharp (from foreground to background), we have deep depth of field. Landscape photography often benefits from this approach.

Four Factors Influencing Bokeh

1. Sensor Size: The size of your camera’s sensor affects depth of field. Larger sensors (common in professional cameras) allow for shallower depth of field, enhancing bokeh.
2. Lens Type: Different lenses produce varying bokeh. Prime lenses (like your EF 50mm) often excel in creating creamy, pleasing backgrounds.
3. Aperture Size: A wide aperture (small f-number) results in shallower depth of field. Experiment with settings like f/1.8 or f/2.8 for beautiful bokeh.
4. Subject-to-Camera and Subject-to-Background Distances: The space between your subject, camera, and background significantly impacts bokeh. Closer subjects with distant backgrounds yield better results.

Demonstrating the Impact of Distance

Cherry Blossoms

These three images of the cherry blossoms clearly demonstrate two key elements of controlling depth of field: the distance of the camera to the subject and the aperture setting of the lens. The largest flower on this branch is roughly the size of the tip of my thumb so the camera is very close – about 9cm from the flower. The rest of the tree is is roughly 45cm from this flower so it’s very close.

The first was taken at f/2.8 and about 90cm from the flower. You can see the image has a very shallow depth of field with a silky bokeh effect making the background extremely ambiguous. Although you get the idea that the flowers are part of a natural background – tree branches, greenery, and other flowers – it’s very soft and draws attention to the bud. The depth of field on this image is about 8cm.

Adjusting the aperture two stops to f/5.6 makes a noticeable difference on the image. Much more of the flower is in focus and you can now see that it’s an entire branch of flowers. Focus has become much sharper on our subject and the tree is coming into focus as is the far background although you still can’t quite make it out enough to identify it with any certainty.

Finally I close the aperture to f/11 and the image is looking very different from the first photo. The flowers are even sharper and a number of buds are now in focus as well. You can now clearly identify the tree and other branches. Greenery in the far distance is becoming identifiable as other shrubs and the gray band is now beginning to look like a driveway with more grass and possibly some trees even further in the distance.

What hasn’t changed is the fact that the background is still pleasantly out of focus! Although the image doesn’t have the same feeling and much more of the background is identifiable the subject is still the clear focus of the photo.

You can clearly see that the closer the camera is to your subject, the shallower the depth of field is even at very small apertures and when the subject is very close to the background.

Statue

You can’t really take a good headshot of a human being with the camera only free feet from your subject at 50mm because all you would see are eyes and that’s it. What we’re looking at is how distance affects depth of field, but now we’ll move the camera back a ways and use a different subject to compensate for how much smaller the subject will appear.

Let’s look at this cute statue. This subject is very low to the ground which will allow me to include some foreground as well to show you how depth of field affects the whole frame. It’s around 20” (50cm) tall so it represents the frame-size of a tight headshot and since my kids weren’t willing to come outside with me, I had to make do! My camera is 6’ (just under 2m) from the subject and the background is roughly 25’ (7.5m) away from the subject. Setting focus for this set of photos was much easier since I was far enough away that I could find focus without having to move the camera closer or farther away. I set the focus on the near eye (camera left eye).

The first image, like the first flower photo, has the aperture set to f/2.8. You can see how much the subject pops out of the background. You can see that the foreground is out of focus and the background, although clearly recognizable as trees, is nicely blurred and no significant distraction. When you look closely at the image you can see that the entire front of the subject is in focus from the toes to the back of the head where the focus starts to fall off. The background goes out of focus very quickly due in part to the fact that the statue is on the top of a small rise.

The next image in the set is set to f/5.6 and the whole frame is starting to come into focus. The foreground is sharpening but is still out of focus enough that it’s not much of a distraction. You can also see that the background is becoming much clearer and is beginning to fight for attention but remains blurry enough that the subject is still the clear focus. Our subject has also sharpened ever so slightly and the edges of the statue are starting to look like a cut-out.

The final image has the aperture set to f/11 and now the whole image is easily identifiable. Although the subject is still the most clearly focused part of the image, everything in the frame is now identifiable. Individual leaves on the rhododendron in the background can be seen, you can start to see some details on the garden tag in the background, and the trees are also now really starting to fight for attention in the frame. The entire statue is now in very sharp focus but the edges of the subject are starting to meld into the background.

Summary

Aperture clearly has a massive impact on the depth of field in an image. If you want to control the bokeh in an image, heading to the aperture setting is your first stop but you can’t end there. The distance of the camera to the subject and the subject to the background also play a significant role in controlling depth of field.

Placing your subject as close to the camera as possible all but guarantees a shallow depth of field. As you saw with the flowers, even at f/11 with the background only inches away from the subject, the depth of field was very shallow. Moving the camera away from the subject six feet required the subject to be pulled off the background significantly to achieve a similar effect.

So if you’re using an entry-level zoom lens and trying to blur the background when you can only stop down to f/5.6 move as close to the subject as you can, pull the subject off the background as much as possible, and voila! Bokeh that pulls your subject out of the frame beautifully!

I hope you found this blog helpful and remember to check back often for new tips and tricks. Until next time, keep taking photos!