Time Lapse
Calculator

The number of frames needed equals the desired final video duration multiplied by its playback frame rate, and the shooting interval equals the total real-world time span divided by that frame count. Shooting a 4-hour sunset into a 10-second, 30fps clip requires 300 frames, one captured roughly every 48 seconds.

Too long an interval makes motion appear jerky or causes fast-changing subjects (like clouds or crowds) to skip unnaturally between frames, while too short an interval wastes storage and shooting time capturing more frames than the final video will actually use. The right interval balances smoothness against the total real-world duration you're compressing.

The compression ratio is simply real-world duration divided by final video duration, so an 8-hour shoot compressed into a 20-second clip has a compression ratio of 1440:1, meaning every second of final video represents 1440 seconds (24 minutes) of real elapsed time. Higher compression ratios need proportionally longer intervals for the same frame count.

Higher playback frame rates (like 60fps vs 24fps) make motion look smoother, but they also require more total frames for the same final duration, meaning either more total shots or a shorter real-world capture window, so the choice trades off smoothness against how much real time you can compress. For most subjects, 24-30fps is plenty smooth.

Flicker in time-lapses usually comes from the camera's auto-exposure or auto-white-balance adjusting slightly between shots taken at different times (especially during changing light like sunrise or sunset), not from an incorrect interval calculation, which is why experienced time-lapse shooters use fully manual exposure settings throughout the shoot.