What is the 180-degree shutter rule for video?

Set your shutter speed to roughly double your frame rate — 1/50s at 24fps, 1/60s at 30fps — to produce motion blur that reads as natural film-style movement rather than the harsh, stroboscopic stutter a much faster shutter produces, or the overly smooth, blurred look a much slower one creates.

Why 'Half the Frame Time' Became the Standard

The rule traces back to mechanical film cameras, where a rotating shutter disc physically covered roughly half of each frame's exposure cycle — a 180-degree disc opening out of a full 360-degree rotation, hence the name. That mechanical proportion happened to produce motion blur that closely matches how the human eye perceives movement, which is why digital video cameras and cinema cameras still target the equivalent exposure time even though none of them use an actual rotating mechanical shutter anymore.

When Deliberately Breaking This Rule Makes Sense

A faster shutter speed than the 180-degree target produces the crisp, hyper-detailed, slightly stuttery look associated with war films and some action sequences — a deliberate stylistic choice, not a technical error. A slower shutter speed produces heavier, dreamier motion blur, sometimes used for a specific artistic effect, though it risks looking simply blurry or low-quality if applied without a clear creative reason. Outside of a specific stylistic goal, the 180-degree target remains the reliable, natural-looking default.

Work out the exact 180-degree shutter speed for any frame rate in the Exposure Triangle Solver, pre-filled near the 1/50s target for 24fps.