Plan the focus before taking the photo
Check optical depth of field with your actual lens settings. This is an estimate of acceptable sharpness; take a test photo to check focus and movement.
Worked example below. Calculate to check your own settings.
Worked example: full frame, 50 mm at f/2.8, focused at 3 m; faces from 2.7 to 3.5 m.
Some face distances fall outside the estimated zone
Green area: estimated focus zone. Black line: focus distance. Brown line and dots: nearest to farthest face. Diagram is a side view; distances below are the calculation results.
- Near limit
- 2.729 m
- Far limit
- 3.33 m
- Total depth
- 0.601 m
- Hyperfocal distance
- 29.812 m
50 mm · f/2.8 · focused at 3 m · CoC 0.03 mm
A setting to test for the group
Alternative focus: 3.048 m. The first listed full-stop setting covering this group at that focus is f/4. This is a model threshold, not a margin for movement. Check lens limits and take a test photo.
Keeping your current focus distance needs at least f/5.6 among the listed full stops.
Compare apertures at your current focus distance
| Aperture | Near | Far | Group fits? |
|---|---|---|---|
| f/1.4 | 2.858 m | 3.156 m | No |
| f/2 | 2.802 m | 3.229 m | No |
| f/2.8 | 2.729 m | 3.33 m | No |
| f/4 | 2.628 m | 3.495 m | No |
| f/5.6 | 2.504 m | 3.742 m | Yes |
| f/8 | 2.338 m | 4.185 m | Yes |
| f/11 | 2.159 m | 4.913 m | Yes |
| f/16 | 1.915 m | 6.919 m | Yes |
| f/22 | 1.687 m | 13.562 m | Yes |
Approximate optical sharpness, not a guarantee of sharp faces. Motion, missed focus, diffraction, lens design, print size and viewing distance also matter.
No photos needed. Input values stay on this page and are not saved or sent in tool analytics.
Explore family portrait styles →Keep the faces you care about in the focus zone
A wide aperture can separate a portrait from its background, but a second face or another row may fall outside the depth of field. Enter the actual focal length printed on your lens, the aperture and the distance you focus at. The calculator shows the near and far limits of estimated acceptable sharpness.
For a couple or group, measure from the camera to the nearest and farthest faces—not the width of the group. The group check compares that interval with the calculated zone. It also finds an alternative focus distance and the first listed full-stop aperture that covers those distances under the selected assumptions. All calculations run on this page; no photo is requested.
What changes when you stop down?
A larger f-number generally increases depth of field at the same focal length and focus distance. Open the comparison table to see that change for your setup. A smaller aperture also lets in less light, so balance it with shutter speed, lighting or ISO. Very small apertures can soften detail through diffraction; the largest f-number is not automatically the best picture.
Keep room for people moving between focusing and pressing the shutter. The calculated boundary is a threshold, not a safety margin. Review a test photo at the size you intend to use. Nikon’s portrait guidance also recommends allowing enough depth of field for the subject.
The calculation and its limits
This tool uses a thin-lens model: H = f² ÷ (N × c) + f; near = s × (H − f) ÷ (H + s − 2f); far = s × (H − f) ÷ (H − s). Here f is actual focal length, N is the f-number, c is the circle of confusion and s is focus distance, all distances in millimetres. When s reaches H, the far limit is infinity. The equations are documented by DOFMaster.
The format presets use conventional circle-of-confusion assumptions: 0.030 mm for full frame, 0.020 mm for 1.5× APS-C, 0.019 mm for 1.6× APS-C and 0.015 mm for Micro Four Thirds. The stricter option halves that tolerance. These are viewing assumptions, not sensor pixel sizes or promises about a particular camera. Larger prints, close inspection and cropping can need a stricter criterion.
For a group spanning distances a to b, the suggested focus is 2ab ÷ (a + b). The tool solves for the aperture needed at both endpoints and rounds up to its next listed full stop. Lens minimum and maximum apertures vary; only use a suggested setting your camera supports. This model does not handle macro magnification, focus breathing, tilt lenses, motion blur or simulated phone portrait blur.
Need to fit everyone into the picture first? Use the camera distance calculator for framing, then return here with your actual lens focal length. Plan the people with portrait pose ideas and the light with the portrait lighting explorer.
How it works
- Choose metres or feet and your camera format. Enter actual lens focal length, aperture and focus distance. The numbers already shown are a worked example.
- For a couple or group, enter the nearest and farthest face distances from the camera. Choose the stricter sharpness assumption if you want to compare a smaller blur tolerance.
- Calculate the focus zone. Compare apertures, copy your plan and test the settings on your camera before taking the final photo.
Frequently asked questions
What aperture should I use for a group portrait?
There is no single f-number for every group. Focal length, focus distance and the depth between the nearest and farthest faces all affect the answer. Enter those distances to compare your current setting with a calculated alternative, then allow for movement and take a test photo.
Should I enter actual or equivalent focal length?
Enter the actual focal length marked on the lens or recorded in the photo metadata, not its 35 mm equivalent. A 35 mm lens on APS-C is still entered as 35 mm. Choose the camera format separately.
Where should I focus for two rows of people?
Measure the nearest and farthest faces. The suggested focus distance balances the modelled blur at those two endpoints. It is not a universal instruction to focus one third of the way into a group. Check the result, your autofocus placement and the lens aperture range with a test photo.
What does infinity mean in a depth of field result?
At or beyond the hyperfocal focus distance, the model has no finite far limit for acceptable sharpness. It does not mean everything is equally sharp: only the focus plane has exact focus in the thin-lens model.
Does this predict phone portrait mode or macro photos?
No. It estimates optical depth of field for the listed camera formats. Software blur, lens-specific focus breathing, macro magnification, subject movement and missed focus are outside the model.
Is the calculator free, and are my measurements saved?
The calculator and copyable plan are free, with no signup or photo upload. Input values stay on the page and are not saved or included in tool analytics. Basic usage events record actions such as calculation and optional portrait-style clicks.
Explore family portrait styles →