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

Lens To Film Millimeters (mm)

Required number input.

Focal Length Millimeters (mm)

Required number input.

Exposure factor caused by lens extension when the lens-to-film distance exceeds focal length: (extension/focal)². 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]

Exposure Factor

The resulting exposure factor returned as a number.

• Exposure arithmetic assumes calibrated ISO, aperture, shutter, flash guide number, and filter density conventions. Lens transmission, reciprocity failure, bellows factors, flash zoom, ambient balance, metering bias, and clipping can alter the practical setting.
• 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.

• Depth Of Field

  Finite depth of field from focal length, f-number, circle of confusion and focus distance using thin-lens near/far limits.

• Depth Of Field Near Limit

  Thin-lens near depth-of-field limit Hs/[H+(s−f)] from hyperfocal distance, focus distance and focal length in matching units.

• Hyperfocal Distance

  Thin-lens hyperfocal distance H=f²/(N·c)+f from focal length, f-number and chosen circle of confusion.