Bokeh is the quality of the blur in the out-of-focus parts of a photograph, not just how much blur there is. A smooth, pleasing background can make a subject stand out, while a busy or harsh one can distract. Several settings and lens traits control how it looks.
What Bokeh Describes
The word comes from a Japanese term for blur, and it has become common in photography circles worldwide. Photographers use it to talk about how bright spots, branches and background textures look when they are not in focus. Points of light turn into soft discs, and the character of those discs, whether smooth, ringed or edged, is part of the bokeh.
What Shapes the Blur
- Aperture: a wider opening (a smaller f-number) gives a shallower depth of field and more blur.
- Focal length: longer lenses make backgrounds look larger and softer relative to the subject.
- Subject distance: the closer you are to the subject, the shallower the focus plane becomes.
- Background distance: the farther the background lies behind the subject, the smoother it becomes.
- Aperture blades: more rounded blades tend to make rounder highlights, while a few straight blades can make polygon shapes.
- Lens design: the optical formula affects whether blur discs look soft or have bright or dark edges.
Steps for a Softer Background
- Choose the widest aperture your lens allows, or a value that still keeps the whole subject sharp.
- Move closer to your subject.
- Place the subject well away from the background.
- Use a longer focal length if you have the choice.
- Look for backgrounds with distant lights, foliage or soft colours that turn into attractive blur.
- Check focus carefully, because a thin focus plane punishes small errors.
Good and Distracting Blur
Smooth blur is often described as creamy, and it tends to come from lenses with well-controlled optical design and rounded aperture blades. A subject that stands clear of a gentle background looks more three-dimensional. Busy blur, sometimes called nervous, shows hard-edged lines or doubled shapes that pull attention away. Both are matters of taste, so look at several sample images from a lens before you decide what you like.
| Factor | Effect on blur |
|---|---|
| Wider aperture | More blur |
| Longer focal length | Larger, softer background |
| Closer subject | Shallower focus |
| More distant background | Smoother blur |
FAQ
Do small sensors make bokeh impossible?
No, but small sensors give more depth of field at the same framing, so blur is harder to achieve. Getting close to the subject and keeping the background far away helps on any camera.
Is more blur always better?
No. Too little depth of field can leave part of a face soft. Choose enough blur to separate the subject while keeping the important details sharp.
The Short Version
Bokeh is the character of out-of-focus areas. Wide apertures, longer focal lengths, close subjects and distant backgrounds all increase it. Balance blur with the amount of sharpness the subject needs.
