The Blurry Background Effect

Have you ever wondered how photographers produce pictures where the background is blurry? In this new age of technology, digital camera manufacturers have made photography easier than ever before. Understanding how to use your camera’s settings to your advantage will help you with many future photography decisions. I will provide you with an in depth explanation about how the Blurry Background Effect works, and walk you through the steps on how to achieve it with your DSLR camera.

Photo by Matt Platz (Click to Enlarge)

What Causes This Effect?

The Blurry Background Effect occurs when the camera’s Depth of Field (DOF) is altered. DOF is defined as the measurable range that the picture is in focus, starting from the lens to as far as the background goes.

Try this: close one of your eyes and put your finger about four inches away from your nose. Now focus your eye on your finger. Notice how the background is blurry? Now try this again, except this time look beyond your finger and focus on the background. Now your finger is blurry, but the background is in focus. This is a demonstration of Depth of Field. Cameras operate in the same way our eyes do. The advantage to the camera is being able to manually select the DOF. (To read more about Depth of Field, visit Cambridge In Colour).

Photo by Matt Platz- Depth Of Field (Click to Enlarge)

How Do I Adjust the DOF On My Camera?

There are three camera settings that affect the outcome of your picture: Shutter Speed, Aperture, and ISO. On your camera, the DOF can be adjusted by changing the aperture. The aperture is expressed in the term f then some number, such as f5.6. In essence, this number system determines how blurry the background will be. The smaller the aperture number, the blurrier the background.

Canon Camera- Aperture Priority Mode

How To Achieve This Effect

You can easily achieve this effect by using Aperture Priority Mode on your DSLR. Your camera probably has a dial on the top. When the dial is turned to Av, you are able to manually select the aperture. The camera does the rest of the work by automatically choosing the shutter speed and ISO for you. To blur the background, select this mode and choose a smaller aperture number to your liking.

Camera Modes Dial

When to Use This Effect

Photographers use this effect to eliminate background distractions within the photograph and draw the eye back to the subject. The Blurry Background Effect should generally be used in low action situations, where the subject is nearly motionless. These could be situations such as a close up of a flower, or a portrait of a face.

When you are using a small aperture number, the lens requires more time to search for the correct focus point. Unless you own a series of professional camera equipment, focusing on a fast moving subject with a small aperture number would be extremely difficult, if not impossible.

Out of Focus Shot

Five Steps to Achieve This Effect

Now that I have provided you with some information on the Blurry Background Effect, I will list out the steps you must take in order to achieve it:

1. Set your camera to Aperture Priority Mode (Av)

2. Adjust the aperture number to a smaller number

3. Make sure your subject is nearly motionless

4. Bring the subject into focus

5. Snap your picture!

Call to Action!

Now that you know how to blur the background of your photos, go out and give it a try! Post in the comments what you will be using this effect for.

Send your pictures to mattplatz@hotmail.com and I will feature them on my blog!

Tune in next week for useful techniques on photographing water!