Have you ever admired photos where the subject is sharp, but the background is beautifully blurred, creating a dreamy effect? This sought-after effect, often called “bokeh,” adds depth and professionalism to your images. You might be wondering how photographers achieve this, especially with elements like twinkling Christmas lights turning into soft, glowing orbs in the background. Let’s explore the secrets behind creating blurry backgrounds and how you can replicate this effect in your own photography, even with just your iPhone.
Let’s visually compare the impact of different lenses on background blur. Below are three photos taken from a similar position, using a 35mm f/1.8 lens, a 50mm f/1.4 lens, and a 70-200mm f/2.8 lens respectively. Observe how the background changes while the subject remains relatively consistent in the frame.
Notice how the Christmas tree in the background appears increasingly blurry as we move from the 35mm to the 70-200mm lens, even though the framing around the subject is similar. This difference is primarily due to depth of field and focal length.
Understanding Depth of Field for Blurry Backgrounds
To achieve a blurry background, a shallow depth of field is essential. Depth of field refers to the area in your photo that appears sharp and in focus. A shallow depth of field means only a small portion of your image is sharp, while the rest is blurred. This is achieved with a wide aperture, indicated by a low f-stop number (like f/1.4, f/1.8, or f/2.8).
However, aperture alone isn’t the only factor. When using a wider lens like a 35mm, even with a wide aperture like f/2.8, the background blur might not be as pronounced if you are very close to both your subject and the background. This is because the distance between you, your subject, and the background influences the degree of blur.
Example of a photo taken with a 35mm lens at f/2.8 showing less background blur due to proximity to the Christmas tree.
In the 50mm example, taken from roughly the same position, you can see a slight increase in background blur compared to the 35mm shot. This is because a longer focal length naturally compresses the background more, contributing to a shallower depth of field effect, even at the same aperture.
Image demonstrating slightly increased background blur with a 50mm lens at f/2.8 compared to a 35mm lens from a similar distance.
The Role of Focal Length and Lens Compression
The most dramatic background blur in the initial comparison is achieved with the 70-200mm lens. To frame the subject similarly to the previous shots with this lens, it was necessary to move significantly further away from the Christmas tree – approximately 15 feet, compared to about 2 feet with the 35mm and 50mm lenses. This increased distance, combined with the longer focal length (shot at 160mm in this case), creates a much more pronounced blurry background.
Photo taken with a 70-200mm lens at 160mm and f/2.8, showcasing significant background blur due to lens compression and distance.
This effect is largely due to “lens compression.” Longer focal lengths compress the perspective, making distant background elements appear larger and closer to the subject. This, in turn, enhances the bokeh effect, making out-of-focus areas appear smoother and more blurred.
Key Takeaways for Achieving Blurry Backgrounds:
- Focal Length Matters: Longer focal lengths (like 85mm, 135mm, or 200mm) are more effective at creating background blur than wider focal lengths (like 35mm or 50mm).
- Distance is Key: Increasing the distance between your subject and the background will significantly enhance the blur. The further the background is, the blurrier it will become.
- Wide Aperture is Crucial: Use a wide aperture (low f-stop number) like f/1.4, f/1.8, f/2, or f/2.8 to minimize depth of field and maximize background blur.
Experimenting with Blurry Backgrounds: Your Turn
Now it’s your turn to experiment! If you have a DSLR or mirrorless camera with interchangeable lenses, try this exercise:
- Set your aperture: Choose the widest aperture your lens allows (lowest f-stop number, ideally f/2.8 or wider).
- Compare focal lengths: Take a photo of a subject (a person or object) using your shortest focal length lens, and then another photo from a similar position using your longest focal length lens. Observe the difference in background blur.
- Distance variation: With a fixed focal length lens, try taking photos of the same subject from different distances, while maintaining similar framing. Notice how the background blur changes as you increase the distance between the subject and the background.
For group photos, a helpful guideline is to set your aperture to match the number of people you are photographing to ensure everyone is in focus. If you are new to manual mode and aperture settings, don’t hesitate to seek further guidance or explore online resources to deepen your understanding.
Blurry Backgrounds in Real-World Scenarios
Here are a few more examples illustrating blurry backgrounds achieved in various photography situations:
Portrait of a person in an urban setting, captured with an 85mm lens at f/1.6, showcasing background lights beautifully blurred.
In this portrait, holiday lights across the street are rendered as a soft, blurred backdrop thanks to the 85mm lens and wide f/1.6 aperture. The distance between the subject and the lights further enhances the bokeh effect.
Wedding photo featuring string lights in the background, blurred using an 85mm lens at f/1.8 due to distance and wide aperture.
Here, string lights at a wedding venue create a magical blurred background. The photographer used an 85mm lens and a wide f/1.8 aperture, combined with distance from the lights, to achieve this effect while keeping the couple sharp.
High school senior portrait with city lights blurred in the distance, captured using a 70-200mm lens at 175mm and f/2.8.
In this senior portrait, city lights in the background are beautifully blurred using a 70-200mm lens at 175mm and f/2.8. The subject’s distance from the background and the longer focal length contribute significantly to the bokeh.
Vertical senior portrait example with background lights blurred, using a 70-200mm lens at 78mm and f/2.8.
Another example from the same senior shoot, this time using the 70-200mm lens at 78mm. Even at a wider end of the zoom range, the background lights are noticeably blurred due to the aperture and distance.
Detail shot from a wedding, with string lights blurred in the background, captured with an 85mm lens at f/2.0.
This detail shot from a wedding showcases how an 85mm lens and f/2.0 aperture can beautifully blur string lights in the background, even when photographing details closer to the subject, by focusing across the room from the lights.
Vertical detail shot from the same wedding, further illustrating background blur with an 85mm lens at f/2.0 and string lights.
A vertical orientation of the previous detail shot, again highlighting the pleasing background blur achieved with an 85mm lens and f/2.0 aperture when photographing wedding details with string lights in the distance.
Achieving Blurry Backgrounds with Your iPhone
Even if you don’t have a DSLR or mirrorless camera, you can still create blurry backgrounds using your iPhone’s Portrait mode. This mode simulates a shallow depth of field using computational photography.
The following examples were taken with an iPhone 11 Pro using the selfie camera. The first image is in standard photo mode, while the second and third are in Portrait mode, simulating apertures of f/16 and f/1.4 respectively.
iPhone Portrait mode artificially blurs the background, but it effectively separates the subject and creates a pleasing bokeh effect. You can even adjust the simulated aperture (f-stop) in Portrait mode, both before and after taking the photo, to control the amount of background blur. Experiment with different f-stop settings to see how they impact the depth of field in your iPhone photos.
Conclusion
Creating blurry backgrounds, or bokeh, is a powerful technique to elevate your photography. By understanding the interplay of aperture, focal length, and distance, you can master this effect and add a professional and artistic touch to your images, whether you’re using a professional camera or just your smartphone. Experiment with these techniques and explore the creative possibilities of blurry backgrounds in your photography.
