Cinematography & Optics Calculators
Lens, framing and exposure math for filmmakers — separate from the storage & media calculators.
See how much of a frame a delivery crop keeps or cuts.
Compare angle of view for two sensor and focal length combinations.
Near and far focus limits, total depth of field, and hyperfocal distance.
Footcandles and lux at key exposure for a given ISO, shutter and frame rate.
Aspect ratio calculator
See how much of a frame a delivery crop keeps or cuts, and compare common resolutions by pixel count.
Common pixel dimensions that preserve this ratio, constrained to fit inside the two standard delivery containers.
| DCI-constrained |
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| 16:9-constrained |
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Crop overlay is calculated from the source and delivery ratios only — it does not read the actual pixel dimensions of a photo, so treat the overlay as illustrative of proportion, not a pixel-accurate crop guide. “Try your own photo” only accepts image files and previews them entirely inside your own browser — nothing is uploaded, saved, or sent to this site or anywhere else.
Field of view comparator
Compare the angle of view for two sensor + focal length combinations side by side.
Field of view is calculated from sensor width/height and focal length using standard optical geometry. The “Real camera modes” group uses active sensor dimensions taken directly from manufacturer-published spec sheets, brochures and user manuals (Sony, ARRI, RED, Canon, Blackmagic, Nikon, Panasonic, DJI) — not estimated. Cameras that only publish a general sensor size (rather than a per-recording-mode active area) are labeled accordingly — the Sony FX6 shares the same full-frame sensor as the FX3 and a7S III. This does not account for lens distortion or breathing — always confirm coverage with the manufacturer or by testing on set.
Depth of field calculator
Estimate near and far focus limits, total depth of field, and hyperfocal distance.
| Full stops | 1/2 stops | 1/3 stops |
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Depth of field is estimated using a circle of confusion derived from the selected sensor’s diagonal (diagonal ÷ 1500), a common approximation. T-stops describe light transmission, not physical aperture size, so a cine lens marked T-stop is converted to an estimated physical f-number (assuming ~80% transmission efficiency, typical of modern coated lenses) before calculating depth of field — actual transmission varies by lens. Acceptable sharpness is also subjective and depends on viewing distance, display size, and lens performance — use as a planning guide, not a substitute for checking focus on a monitor.
Exposure table
Generate an exposure table at “key” 18% gray for a given ISO, shutter and frame rate.
| T-stop | Footcandles | Lux |
|---|
Exposure values are calculated using a standard reflected-light formula calibrated to 18% gray. Actual light meters and camera metering systems use manufacturer-specific calibration constants that can vary by a third of a stop or more — always confirm exposure with a meter or the camera’s own tools before a critical shoot.
Quick answers
Direct numbers for the most common lens and exposure questions.
Where the math comes from
Field of view, depth of field, and exposure calculations use standard, published optical and photographic formulas. They are planning tools, not a substitute for testing lenses or metering light on set.
Sensor size presets
Sensor dimensions used are common industry-standard sizes (full frame, Super 35, APS-C, Micro Four Thirds, Super 16, and small-format 1", 2/3", 1/1.7" and 1/2.3" sensors) — the smaller presets cover most drones, action cameras and gimbal cameras. Your specific camera’s active sensor area may vary slightly by recording mode.
Runs entirely in your browser
Nothing you enter here is uploaded or stored — every calculation happens locally on your device.