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

Source Aspect Ratio

Required number input.

Target Aspect Ratio

Required number input.

Fraction of source image height retained when cropping to a wider target aspect ratio at unchanged width. 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]

Retained Height Fraction

The resulting retained height fraction 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.

• Aspect Ratio Calculation

  Unreduced width-to-height aspect ratio for an image or screen measured in matching units.

• Aspect Ratio From Resolution

  Display width-to-height aspect ratio from integer pixel dimensions; does not simplify to a fraction.

• Resolution From Aspect Ratio

  Rounded integer pixel width required for a given height and positive width-to-height aspect ratio.