Current frame
{{ frameCoverageLabel }}
{{ angleSummary }}
{{ lensClassBadge.label }} {{ equivalentFocalLabel }} {{ targetFitBadge.label }}
Camera Frame {{ fieldWidthLabel }} {{ visualNumericMarker }}
Start from portrait, room, product, video, surveillance, wildlife, or aerial framing values.
Choose how distances and frame sizes are entered and displayed.
Pick a camera format preset, or use Custom plus Advanced sensor dimensions.
Use the orientation of the final still, video, or inspection frame.
Shorter focal lengths widen the frame; longer focal lengths narrow it.
mm
Frame coverage is calculated on this plane.
Used to estimate the lens focal length needed for a required scene width.
Enter the native sensor width x height in millimetres.
mm
to mm
points
Metric Value Detail Copy
{{ row.metric }} {{ row.value }} {{ row.detail }}
Lens Horizontal FOV Frame width Frame height Use cue Copy
{{ row.lens }} {{ row.horizontal }} {{ row.width }} {{ row.height }} {{ row.use }}
Cue Status Planning note Copy
{{ row.cue }} {{ row.status }} {{ row.note }}
Tags: Education, Photography, Videography
Depth of Field Calculator Plan depth of field from lens, aperture, sensor format, focus distance, circle of confusion, background blur, framing, and motion checks.
ND Filter Exposure Calculator Calculate ND filter stops from metered and target exposure settings, then compare fixed, stacked, and variable filter choices for stills or video.
Time-lapse Plan Calculator Build a time-lapse shoot plan with interval, clip length, frame count, storage, battery, and exposure-gap warnings before setting the camera.
Lens Equivalence Comparator Match lenses across camera formats with target focal length, depth-of-field look, video crop adjustments, and practical lens candidates.
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Advanced
:

Framing starts with geometry before it becomes an artistic choice. A lens projects a cone of view onto the active sensor area, and that cone covers a measurable width and height at the subject distance. When the camera is too close, even a wide lens may miss the edges of a room. When the camera is far away, a moderate lens may frame a whole product table, inspection bay, or animal enclosure without changing the lens at all.

Focal length is only one part of that relationship. A 24 mm lens records a broad view on a 36 x 24 mm sensor, but the same lens on a smaller sensor records a narrower crop from the middle of the image circle. The focal length printed on the lens stays 24 mm. What changes is the angle recorded by the active sensor area, which is why sensor format and frame orientation belong in the same framing calculation as focal length.

Angle of view
The angular span captured by the lens and sensor, usually read horizontally, vertically, or diagonally.
Field of view
The physical scene width and height visible at a chosen camera-to-subject distance.
Subject plane
The flat wall, table, ground strip, doorway, or target area where the frame coverage is being estimated.
Equivalent focal length
A 35 mm full-frame comparison number. It compares framing across formats, but it does not change the real lens focal length.
Camera field of view geometry A camera projects an angle of view toward a scene plane where subject distance determines the covered scene width. camera angle of view scene width subject distance sensor size and focal length set the cone

Distance is the part that turns an angle into a real-world measurement. At the same focal length and sensor size, doubling the camera-to-subject distance doubles the covered width and height on a flat subject plane. Moving the camera also changes perspective, foreground scale, and background size, so the framing number answers coverage, not the whole look of the image.

Real camera modes can narrow the active area. Video crops, stabilization, digital zoom, aspect-ratio crops, and open-gate choices may use a different width and height than a sensor marketing label suggests. Close focus can also change framing on lenses that breathe as they focus. For fisheye or heavily corrected action-camera footage, simple rectilinear field-of-view math is only a rough planning guide because the projection itself is different.

A field-of-view estimate is most useful before a shoot, installation, inspection, or mapping pass. It helps choose a lens, decide whether the camera can stay where it is, and check whether a required target width fits with enough margin. It cannot guarantee edge coverage when the setup is close to the limit, so tight plans still deserve a real test frame or manufacturer-specific active-sensor data.

How to Use This Tool:

Start from the setup that best resembles the job, then adjust the actual camera, lens, and distance values until the current coverage and target-width status match the framing problem.

  1. Choose a Setup preset such as Room interior, Product tabletop, Talking-head video, Surveillance corridor, Wildlife scout, Aerial mapping pass, Portrait half-body, or Custom. The preset fills realistic starting values that you can still edit.
  2. Set Units, Sensor format, and Frame orientation. If the active recording area is not listed, open Advanced and enter Custom sensor size.
  3. Enter Focal length as the actual lens value in millimeters. Do not enter a full-frame equivalent number, because the selected sensor format already handles the crop-aware comparison.
  4. Enter Subject distance as the camera-to-scene-plane distance. The summary updates frame coverage, horizontal and vertical angles, diagonal lens class, and full-frame equivalent framing.
  5. Use Target frame width when the job starts from a required scene width. Set it to zero when you only need the angle and current frame coverage.
  6. Use Lens sweep range and Sweep samples in Advanced to shape the Lens Coverage Table and FOV Width Sweep chart. These controls compare lenses at the same distance and sensor setup.
  7. Resolve any Check the camera setup warning before relying on the results. Common causes are a focal length or subject distance at zero, a negative target width, custom sensor dimensions at zero, or a sweep range whose minimum is not below its maximum.

Interpreting Results:

Frame coverage is the main number when the question is physical fit. It estimates the width and height of a flat scene plane at the entered distance. Angle of view is better for comparing lenses, sensor formats, and camera modes because it describes the cone before that cone reaches a subject distance.

Target width fit compares the calculated horizontal frame width with the requested target width. Target fits means the frame is at least 10% wider than the target. Tight fit means the target fits with less than 10% spare width. Needs wider lens means the current lens and camera position do not cover the requested width.

  • Coverage Details: check sensor gate, crop factor, equivalent focal length, target margin, lens needed for the target width, and distance needed for the current lens.
  • Lens Coverage Table: compare common focal lengths and the selected sweep range using the same subject distance.
  • Framing Guide: read target coverage, lens category, practical lens pick, camera placement, crop awareness, and rectilinear-assumption notes before treating the plan as shoot-ready.
  • FOV Width Sweep: use the chart to see how frame width and height shrink as focal length increases. If the chart cannot render, the lens table carries the same comparison data.
  • JSON: copy or download the numeric result when the calculation needs to stay with a shot plan, inspection note, or documentation record.

The main false-confidence risk is treating a close pass as exact. If a target barely fits, add margin or shoot a test frame. A small crop, focus-breathing shift, lens distortion correction, or distance measurement error can remove the spare width shown in the estimate.

Technical Details:

Rectilinear field of view is a triangle calculation. The active sensor dimension forms one side of the imaging geometry, the focal length sets the angle, and the subject distance projects that angle onto a flat scene plane. Horizontal, vertical, and diagonal angles use the corresponding active sensor dimensions. Portrait orientation swaps the active horizontal and vertical dimensions, while the native diagonal still controls crop factor.

The calculation assumes a flat subject plane parallel to the sensor. That model fits rooms, product tables, walls, corridors, copy stands, inspection targets, and many aerial-planning sketches. It becomes less reliable for curved scenes, very close subjects, fisheye lenses, action-camera distortion correction, and recording modes that crop the sensor before saving the frame.

Formula Core:

The angle equation uses millimeters for sensor size and focal length. Distance and target width are converted to the selected display unit for comparison, but the geometric relationship stays the same.

αs = 2⁢arctan(s2f) Fs = 2D⁢tan(αs2) ftarget = wDT Dtarget = Tfw crop factor = 43.27wn2+hn2 f35 = f×crop factor
Symbol Meaning Visible source
s Sensor dimension used for one angle calculation. Sensor format, custom sensor size, and frame orientation.
w, h Active horizontal and vertical sensor dimensions after orientation is applied. Selected sensor format or custom sensor size.
wn, hn Native sensor width and height before any portrait-orientation swap. Selected sensor format or custom sensor size.
f Actual focal length in millimeters. Focal length field.
D Camera-to-scene-plane distance. Subject distance after unit conversion.
T Requested horizontal scene width. Target frame width after unit conversion.

For a full-frame 36 x 24 mm setup with a 24 mm lens at 4 m, the horizontal angle is about 73.7 deg and the vertical angle is about 53.1 deg. The projected frame is about 6.00 m x 4.00 m. With a 5 m target width, the fit ratio is 1.20, leaving about 1.00 m of spare width. Reversing the same geometry gives about 28.8 mm as the focal length that would make the 5 m target width fill the frame at that distance.

Lens Class Rules:

Lens class labels come from diagonal angle of view. They are practical framing cues, not image-quality ratings.

Label Diagonal angle rule Practical meaning
Ultra-wide At least 100 deg. Very broad coverage where distortion, edge stretching, and active crop deserve extra checking.
Wide At least 75 deg and below 100 deg. Useful for interiors, landscapes, architecture, and wide establishing views.
Standard wide At least 55 deg and below 75 deg. Moderately broad framing with less dramatic edge expansion than an ultra-wide view.
Normal At least 38 deg and below 55 deg. Middle framing where camera position usually matters more than lens drama.
Short telephoto At least 20 deg and below 38 deg. Narrower framing often used for portraits, products, and detail isolation.
Telephoto At least 8 deg and below 20 deg. Tight framing for distant subjects, sports, wildlife, or surveillance details.
Super telephoto Below 8 deg. Very narrow framing where small aiming, distance, or support errors are obvious.

Target Fit Rules:

Target fit compares calculated horizontal frame width against the requested target width. A target width of zero turns this check off.

Status Rule Meaning
Target fits Frame width divided by target width is at least 1.10. The requested scene width fits with practical horizontal margin.
Tight fit Frame width divided by target width is at least 1.00 and below 1.10. The target fits, but a small crop or measurement error may matter.
Needs wider lens Frame width is below the target width. Use a shorter focal length, move the camera back, or reduce the required target width.

Displayed angles are rounded to one decimal place, target focal length estimates to one decimal millimeter, and physical lengths to readable metric or imperial units. Repeated runs with the same sensor size, orientation, focal length, distance, and target width produce the same geometric result.

Limitations:

Field-of-view estimates are useful planning numbers, but the real frame can differ when the lens, camera mode, or subject does not match the rectilinear geometry model.

  • Fisheye lenses and heavily distorted wide lenses use projections that do not match simple rectilinear angle math.
  • Focus breathing can change framing at close focus compared with the lens marking or infinity-focused specification.
  • Video crops, stabilization, digital zoom, open-gate modes, and aspect-ratio crops may use less than the full sensor area.
  • Sensor labels are approximations. Phone, action, compact, cinema, and specialty cameras can use active dimensions that differ from a common format name.
  • The result does not estimate depth of field, exposure, resolution, motion blur, image quality, distortion correction, or whether a lens physically covers the selected sensor.

Worked Examples:

Room interior. A full-frame camera in landscape orientation with a 24 mm lens at 4 m covers about 6.00 m x 4.00 m, with an angle of view near 73.7 deg horizontal and 53.1 deg vertical. With a 5 m target width, Target width fit shows spare width, and Lens for target width is about 28.8 mm.

Talking-head video on APS-C. An APS-C 1.5x setup with a 35 mm lens at 1.8 m covers about 1.21 m x 0.80 m. If the target frame width is 1.6 m, the current setup is short and the required lens is about 26.4 mm. Moving back also increases coverage, but it changes perspective and background size.

Product tabletop. A full-frame camera with a 70 mm lens at 0.8 m covers about 41 cm x 27 cm. A 60 cm target width needs either a focal length near 46.7 mm at the same distance or the same 70 mm lens moved to roughly 1.17 m. In close product work, leave extra margin because focusing distance and lens breathing can shift the frame.

Wildlife scout. An APS-C setup with a 400 mm lens at 30 m gives a narrow horizontal angle near 3.4 deg and covers about 1.76 m x 1.17 m. A 3 m target width therefore needs wider framing, while the full-frame equivalent is roughly 614 mm. That reach is useful for detail but too tight for a larger animal or environmental frame.

Troubleshooting. If the warning says the lens sweep range must use a positive minimum below the maximum, a range such as 200 mm to 10 mm cannot build comparison rows. Change it to a range such as 10 mm to 200 mm, then recheck Lens Coverage Table and FOV Width Sweep against the same subject distance.

FAQ:

Should I enter the focal length printed on the lens or the full-frame equivalent?

Enter the actual focal length printed on the lens. The selected sensor format handles crop-aware framing, and Full-frame equivalent is reported as a comparison only.

Why does portrait orientation change the width and height?

Portrait orientation swaps the active sensor width and height for horizontal and vertical coverage. The native sensor diagonal still controls crop factor and full-frame equivalent framing.

What does target width do?

Target frame width checks whether the current setup covers a required horizontal scene width. It also estimates the focal length and camera distance that would make that width fill the frame.

Why does my real lens show a different frame than the estimate?

The estimate assumes rectilinear geometry, the selected active sensor dimensions, and a flat scene plane. Fisheye projection, distortion correction, focus breathing, video crops, stabilization crops, and exact sensor dimensions can shift the real frame.

Why am I getting a camera setup warning?

Common causes are a focal length or subject distance at zero, a negative target width, custom sensor dimensions at zero, or a lens sweep minimum that is equal to or higher than the maximum.

Does entering camera setup data upload anything?

No calculation upload is needed. The camera values are calculated in the browser, and copied or downloaded outputs are created only when you choose those actions.

Glossary:

Angle of view
The angular span captured by the camera for a selected sensor dimension and focal length.
Field of view
The physical width or height visible on the subject plane at the entered distance.
Crop factor
The ratio between a 36 x 24 mm frame diagonal and the selected sensor's native diagonal.
Full-frame equivalent
The focal length on a 36 x 24 mm frame that would give a similar angle of view.
Rectilinear lens
A lens projection that aims to keep straight lines in the scene straight in the image.
Focus breathing
A framing change caused by a lens changing its effective angle of view as focus distance changes.

References: