Depth of field and field of view for a photo

Open Camera & optics

Open a JPEG, PNG or WebP photo straight from your camera or phone with Open photo. Then choose Tools in the left rail and press Camera & optics. In Photo Lab you can do the same for one photo of a set: select it and press Camera & optics for this photo.

Lumina reads the camera data (EXIF) of the photo on your device and fills in the form. The line under the heading tells you what it found, for example “Camera data read from the photo: Fujifilm X-T30.” It also says when it had to estimate the sensor size from the 35 mm-equivalent focal length, or when the photo does not record the focus distance (3 m is then assumed). Photos that went through messaging apps or editors often carry no camera data; enter the values yourself, or use Read settings from a photo file… to load them from the original.

Check the camera and lens

In Camera and lens:

• Sensor size — pick your format, from full frame and APS-C to the small phone types, or Custom size to type the width and height in millimetres.
• Focal length (mm) — the real focal length written on the lens, not the 35 mm equivalent.
• Aperture (f-number) and Focus distance (m) — the distance from the lens to the subject in focus.
• Image width (px, optional) — the long side in pixels; it gives the pixel pitch for the star rule.

Every change updates the results at once.

Read the depth of field

The bold line at the top of the results is the summary, for example “23 mm at f/2 on APS-C …, focused at 3 m: sharp from 2.476 m to 3.805 m, a depth of field of 1.329 m.” Below it you find the Near limit, Far limit, Total depth of field and Hyperfocal distance, a distance scale with the sharp zone, and the table Depth of field at other apertures that shows what stopping down would have changed.

Focus at the hyperfocal distance and everything from half that distance to infinity is acceptably sharp — the table row Focused at the hyperfocal distance: sharp from gives that distance.

Choose how strict “sharp” is

Under Sharpness criterion, Acceptable blur decides the circle of confusion:

• Sensor diagonal ÷ 1500 (classic standard) — the usual value; change Divide the sensor diagonal by to be stricter (for example 3000).
• From a print size and viewing distance — enter the print width and height, the viewing distance and the visual acuity. A big print viewed closely gives a smaller sharp zone.
• My own circle of confusion — type a value in millimetres.

Field of view and equivalence

The Field of view table lists the horizontal, vertical and diagonal angle and the width and height of the scene covered at the focus distance. Full-frame equivalence shows the crop factor, the full-frame focal length with the same view and the f-number that gives the same depth of field.

ND filters and stars

In Exposure, ND filter and stars, enter the Shutter time (1/125 or seconds) and ISO to see the exposure value. Type an ND filter strength and choose ND filter given as stops, optical density or filter factor: the table Exposure and ND filter converts between them and gives the new shutter time, for example 1/250 s with a 6-stop filter becomes 1/4 s.

For night skies, the table Star photos: longest exposure without visible trails compares the 500 rule with the NPF rule. The NPF rule needs the image width; Star declination (°) makes it longer for stars near the celestial pole.

Use the same numbers elsewhere

The link Depth of Field calculator (tool page and API) opens the same calculation as a standalone tool with a JSON API and MCP access for scripts and AI agents. Nothing in this dialog is uploaded; the photo stays on your device.