Blurring the background of your photos, also known as achieving a shallow depth of field or bokeh, is a powerful technique that draws the viewer's eye to your subject and creates a professional, aesthetically pleasing image. It's a skill every DSLR photographer should master. This guide provides useful tips to help you learn how to blur backgrounds effectively using your DSLR camera.
Understanding Depth of Field
Before diving into techniques, it's crucial to understand depth of field (DOF). DOF refers to the area of your image that appears sharp and in focus. A shallow DOF means only a small area is in focus, while a deep DOF means a larger area is sharp. Blurring the background requires a shallow DOF.
Key Factors Affecting Depth of Field:
-
Aperture: This is the most important factor. A wide open aperture (low f-number, like f/1.4, f/2.8, or f/4) results in a shallow DOF and significant background blur. A narrow aperture (high f-number, like f/16 or f/22) results in a deep DOF with a sharp background. Learn to understand your lens's aperture range.
-
Focal Length: Longer focal lengths (e.g., 70mm, 100mm, 200mm) create a shallower DOF than shorter focal lengths (e.g., 24mm, 35mm). This is why telephoto lenses are popular for portrait photography where background blur is desired.
-
Distance to Subject: The closer you are to your subject, the shallower the DOF will be. Conversely, the further away you are, the deeper the DOF.
-
Sensor Size: Larger sensors (like those found in full-frame DSLRs) generally produce a shallower DOF compared to smaller sensors (like those in APS-C cameras).
Mastering the Technique: How to Blur Backgrounds
Here's a step-by-step guide on how to achieve that desirable background blur:
-
Choose the Right Lens: Prime lenses (lenses with a fixed focal length) often have wider maximum apertures (e.g., f/1.8, f/1.4) than zoom lenses, making them ideal for shallow depth of field. A 50mm f/1.8 or an 85mm f/1.8 are excellent choices for portrait photography.
-
Set Your Aperture: Select the widest aperture your lens allows (the lowest f-number). Experiment to find the sweet spot that provides the desired amount of background blur while still keeping your subject acceptably sharp.
-
Adjust Your Focus: Use your DSLR's autofocus system to precisely focus on your subject. Make sure your subject is sharply in focus before taking the shot. Consider using single-point autofocus to focus specifically on the eyes in portraits.
-
Position Your Subject: Position your subject at a distance from the background. The further the background is from your subject, the more blurred it will appear.
-
Shoot in the Right Light: Good lighting conditions are essential. Adequate light allows you to use a wider aperture without compromising your shutter speed (preventing motion blur).
-
Consider Your Composition: Think about the background elements. A busy background will be more difficult to blur effectively. Choose a background that complements your subject and won't distract from it, even when blurred.
-
Post-Processing: While in-camera techniques are crucial, post-processing tools like Adobe Photoshop or Lightroom can help refine the blur and enhance the overall look of your image. However, don't rely solely on post-processing to create a blurred background; mastering the in-camera techniques is key.
Practice Makes Perfect
The best way to learn how to blur backgrounds is through practice. Experiment with different settings, distances, and lenses to see how they affect your depth of field. Take lots of photos and analyze the results. Over time, you'll develop a keen eye for creating stunning images with beautifully blurred backgrounds. Remember to review your images critically to identify areas for improvement.
Don't be discouraged if your first attempts aren't perfect. Mastering DSLR photography takes time and dedication. Keep practicing, and you'll soon be able to confidently create professional-looking photos with beautifully blurred backgrounds.
