I never intentionally sought to create bokeh backgrounds. In fact, I only learned about bokeh fairly recently. But I have been taking photos with those fuzzy backgrounds for a long time, playing with different combinations of depth-of-field and aperture settings to create what I liked to call “3D” photos. I am a food blogger, after all, and the 3D effect works wonders in food photography. After I learned about bokeh, I went through the thousands of photos in my hard drive and was surprised how many of them had the kind of background that have come to be known in photography as bokeh.
What is bokeh?
Bokeh… is a photographic term referring to the appearance of out-of-focus areas in an image produced by a camera lens using a shallow depth of field. Different lens bokeh produces different aesthetic qualities in out-of-focus backgrounds, which are often used to reduce distractions and emphasize the primary subject. [Wikipedia]
If you want to get into the technical aspect of creating bokeh, read this and this. The second link is especially interesting as it includes the result of bokeh experiments using various camera lenses.
There is really no good or bad lens for creating bokeh in photos as the quality of blurring also depends on the distance of the subject to the objects in the background. A 50mm lens set at f/1.8 can create good quality blurring if the distance between subject and background is a mere few feet. But if the distance is longer, the background can be washed out.
One thing seems clear, however — good or bad bokeh is not always the result of technical skill nor the kind of lens used. In many cases, what is good or bad bokeh is a subjective thing since the ultimate test is whether the bokeh is pleasing to the eye. And that is something that will always vary from one viewer to the next.
Sunlight filtering through the leaves of the tree created the bokeh in the photo above. If you’re wondering what camera and settings I used:
Camera: Canon EOS 40D
Shutter speed: 1/85 sec
Exposure program: Manual
Aperture Value: f/4.6
ISO Speed Ratings: 400
Focal Length: 105.0 mm
Below, another tree trunk similarly photographed.
Is the appearance of the light spheres necessary for a photo to be considered to have bokeh? Some seem to think so and it might be redundant to say it again but the concept of bokeh is a pretty subjective one. As far as I’m concerned, good bokeh simply means the background is pleasantly blurred to make the subject pop out of the picture.
Just how blurred should the background be for it to be considered bokeh? Personally, I have no idea. Photographers are in a constant state of disagreement although most agree that background objects should have no hard edges. Just how fuzzy the edges should be for them not to be considered “hard” is beyond me.
In macro photography, it is often tempting to go to extremes and open the aperture as wide as it can go to create an extremely blurred background. But there are cases when the background can actually enhance the subject and make it pop out even better. In such cases, less blurring becomes more effective. Take the photo of a cosmos flower above, for instance. By only slightly blurring the green leaves but still allowing them to remain an integral part of the photo, the flower appears more natural as it is set against its most natural setting — its own leaves. Bright yellow against green works visually well too.
But if you have to have those little light spheres, the effect can be created in many surprising ways.
Those are DVD cases, standing side by side on a shelf, behind Yoda. What created the white spheres? They are the result of lens blur and the reflection of the overhead light on the DVD cases with dark background and white text. You can actually make out some of the letters especially on the right side of the photo.
A direct source of light in the background is not always necessary to create a bokeh background effect. In this photo, the out-of-focus white flowers and green leaves, both lighter than the rest of the colors in the background, create interesting patterns.
So, you like bokeh? There are only two things to learn, really — depth-of-field and aperture settings. Experiment, experiment, experiment. :)