Planning a Smooth Speed Ramp

A speed ramp gradually changes the capture frame rate during a single continuous shot, so the footage eases into or out of slow motion instead of cutting hard between speeds. Getting the start and end frame rates right — and knowing how long the resulting clip will actually play — makes the difference between a smooth, intentional ramp and a jarring one.

Reading Speed as a Multiplier

Speed is simply the ratio of capture frame rate to playback frame rate. Capturing at the same rate you’ll play back gives normal 1× speed. Capturing faster than playback stretches time into slow motion; capturing slower speeds it up. A ramp from 24fps to 120fps played back at 24fps moves from real-time at the start to 5× slow motion at the end.

Why the Resulting Duration Matters

A ramping shot doesn’t produce a simple, single-speed duration — the playback length grows as the average of the start and end speeds across the capture time. Knowing the resulting duration in advance helps you time a ramp to hit a beat, a cut point, or a specific moment in the action.

This tool is especially useful for:

• Cinematographers planning in-camera or post-produced frame rate ramps.
• Editors timing a ramp to land on a specific cut point or beat.
• Anyone planning action or sports footage that needs to ease into slow motion.