Use this cinematography or projection calculation to plan image geometry, exposure, timing, storage, film footage, or presentation from explicitly stated camera and display parameters.

Actual Focal Millimeters (mm)

Required number input.

Crop Factor

Required number input.

Equivalent field-of-view focal length from an actual focal length times a supplied crop factor. The tool evaluates the supplied inputs together and returns the named outputs below; it does not infer omitted operating conditions or change the units shown.^[1]

Equivalent Focal Millimeters (mm)

The resulting equivalent focal millimeters returned as a number.

• Angle-of-view and equivalent-focal-length calculations use nominal sensor or film dimensions and an ideal rectilinear lens. Focus breathing, distortion, image-circle cropping, stabilization, anamorphic optics, and manufacturer crop conventions can change the captured field.
• Use finite inputs in the displayed units and preserve more precision than the final presentation requires. Independently verify safety-critical, financial, compliance, or production decisions.

Confirm critical values with the actual camera, lens, codec, projector, and delivery specification, then run a camera or projection test under representative conditions.

• Field Of View From Focal Length

  Horizontal angle of view of a rectilinear lens from sensor width and focal length; excludes distortion.

• Focal Length From Field Of View

  Focal length from sensor width and horizontal angle of view under a rectilinear thin-lens model.

• 35mm Equivalent Focal Length

  35 mm full-frame-equivalent focal length using the 36×24 mm diagonal divided by the camera sensor diagonal.