What makes a background blurry?
A blurry background comes from a shallow depth of field: only a thin slice of the scene is in focus, and everything outside it softens. The soft, out-of-focus look is often called bokeh, although strictly that word describes the quality of the blur. Four things control how much blur you get, and you can combine them.
Quick settings
- Set the camera to Aperture Priority (A or Av), or manual.
- Choose the lowest f-number your lens allows, such as f/1.8, f/2.8 or f/4.
- Focus on your subject, ideally on the eye in a portrait.
- Move your subject well away from the background.
- Zoom in or step closer to your subject.
- Check your shutter speed, and lower ISO or add light if needed.
The four levers
Aperture
A smaller f-number means a wider opening and a shallower depth of field. Going from f/8 to f/2.8 makes a visible difference. The widest aperture depends on your lens: many kit zooms open to around f/3.5 to f/5.6, while prime lenses commonly reach f/1.8 or wider.
Distance from camera to subject
The closer you are to your subject, the shallower the depth of field becomes. Stepping in a few paces can increase blur more than you expect, though your framing changes too.
Distance from subject to background
Blur grows as the background moves farther behind your subject. A person standing against a wall will show little blur, while the same person standing well in front of distant trees will show much more. This is the easiest lever on any camera, including a phone.
Focal length
A longer focal length makes the background look more compressed and blurrier at a similar subject size. An 85mm or 135mm lens, or zooming a kit lens to its long end, will usually blur a background more than a wide-angle lens, if you keep your subject the same size in the frame by standing farther back.
Getting the most from a kit lens
If your lens only opens to f/5.6 at the long end, you can still get decent separation:
- Zoom to the longest focal length.
- Stand close to your subject.
- Pull the subject as far from the background as you can.
- Choose a plain, distant background.
Many people also buy a fast prime lens such as a 50mm f/1.8, which is often affordable and makes blur much easier. See the best portrait lens for focal length options.
Sensor size
Larger sensors generally give shallower depth of field for the same framing and aperture. That is why phones, which have tiny sensors, struggle with natural background blur, and why full-frame cameras often render it more easily than smaller-sensor cameras. It is a general tendency rather than a rule that stops you from getting a good result on any camera.
Phone portrait mode
Phones usually simulate blur with software, sometimes using depth data from a second lens or sensor. To get the best results:
- Switch to Portrait mode.
- Stay within the distance range the app recommends.
- Keep your subject clearly separated from the background.
- Check edges, such as hair and glasses, where software can slip.
Many phones let you adjust the strength of the effect while shooting or afterward in the photo editor, and some let you remove it entirely. If you want less blur, look for an option to adjust the depth or aperture value on the photo, or take the picture in regular Photo mode instead. Features differ by phone model, so check yours.
When you want less blur
If blur is too strong, do the opposite:
- Use a higher f-number, such as f/8.
- Step back from the subject or zoom out.
- Move the subject closer to the background.
For scenes that should be sharp from front to back, see the hyperfocal distance guide.
Blurry background versus a blurry photo
A soft background is intentional. A blurry subject is a problem. If the subject is soft too, the cause could be:
- Missed focus. At wide apertures the sharp zone is thin, so a small error shows. Review camera focus points and autofocus modes.
- A slow shutter speed causing camera shake or subject motion (see shutter speed for portrait photography).
- A smudged lens or filter.
If you cannot tell which, zoom in on the eye or the subject’s sharpest edge and compare.
Common mistakes
- Using the lowest f-number but leaving the subject right in front of the background
- Focusing on the wrong thing, so the face is blurred and the background is sharp
- Over-relying on phone software around hair and complex edges
- Setting the widest aperture for a group, where some faces will fall outside the focus zone
For the bigger picture of using focus and blur together, read how to create depth in your photography, or return to the basics in how to focus your camera.