Depth of Field Simulator
Change the lens, aperture, sensor and focus distance and watch the background blur and the sharp zone respond. The numbers use the same formulas as any depth of field calculator, and the preview applies them to every layer of the scene.
A drawn scene with five layers at fixed distances: the flowers 1 m away, the person 3.5 m, trees 40 m, distant hills and sky far beyond. The blur on each layer is worked out from the real optics for your settings; the framing is approximate.
Settings
Sharp from 3.42 m to 3.59 m, a zone 17 cm deep.
- Near limit
- 3.42 m
- Far limit
- 3.59 m
- Total depth
- 17 cm
- Hyperfocal distance
- 139 m
Hyperfocal distance: focus here and everything from half this distance to infinity is sharp (circle of confusion 0.029 mm, the sensor diagonal divided by 1,500).
For more background blur
- Open the aperture (a smaller f-number).
- Use a longer lens, or step closer to your subject.
- Put more distance between the subject and the background.
- A bigger sensor gives a thinner zone for the same framing and f-number.
What is depth of field?
Depth of field is the range of distances, in front of and behind the point you focus on, that looks acceptably sharp in the picture. Beyond it, things soften gradually. It is not a switch from sharp to blurry: the near and far limits in the calculator mark where the softness becomes noticeable at normal viewing size.
What controls it
- Aperture. A wider opening (a smaller f-number such as f/1.8) gives a thinner sharp zone and a softer background. A narrower opening (f/11 or f/16) gives more of the scene in focus.
- Focal length. At the same distance and f-number, a longer lens gives a thinner zone, because the subject is magnified more.
- Distance to the subject. The closer you focus, the thinner the zone. Doubling the distance makes the zone roughly four times deeper.
- Sensor size. For the same framing and the same f-number, a bigger sensor gives a thinner zone, which is why full-frame and medium-format cameras are known for soft backgrounds and phones for deep focus.
How to use the simulator
Pick an example (Portrait, Street, Landscape, Close-up, Phone) or set your own camera and lens. The diagram shows where the sharp zone lies between you and the horizon; the five layers of the scene (flowers, person, trees, hills, sky) blur according to how far each one is from your focus point.
Depth of field questions
What is the hyperfocal distance?
It is the closest focus distance at which everything from half that distance to infinity is acceptably sharp. Landscape photographers focus there to keep the whole scene sharp. It gets shorter with a wider lens and a smaller aperture.
Why is more of the sharp zone behind the focus point than in front of it?
At typical distances about one third of the zone lies in front of the point you focus on and two thirds behind it. The two parts become equal only at very close, macro distances.
Does a full-frame camera really blur backgrounds more than a crop sensor?
Yes, when you frame the shot the same way and use the same f-number. A full-frame camera needs a longer lens (or a closer position) to match the framing of a crop-sensor camera, and that gives the thinner zone. Use the sensor menu above to compare.
Is f/22 the sharpest setting?
No. A very small aperture gives the deepest zone, but diffraction starts to soften the fine detail of the whole picture, usually beyond about f/11 to f/16. Use the widest aperture that still gives the depth you need.
Can a phone make blurry backgrounds?
Phone cameras have small sensors and short lenses, so their natural zone is deep. Portrait mode adds the blur with software, which is an imitation of the optical effect shown here.
How accurate is the calculator?
The near limit, far limit and hyperfocal distance follow the standard thin-lens formulas with a circle of confusion of the sensor diagonal divided by 1,500. Other calculators may use a slightly different convention, so their numbers can differ by a few percent. The scene preview is an illustration, not a photograph.