Pick which of the three you want to solve for — shooting interval, clip length, or event duration — and PhotoPills fills in the rest, along with how many photos you'll need and how much memory card space to bring.

Tap Calculate to choose which one you're solving for, then fill in the other two plus your frame rate and file size — the settings box handles the rest.

Never shot a time lapse of this particular subject before? The Interval Table gives you a tested starting interval and typical duration — from fast-moving clouds (1 second) to a slow sunset (1–3 seconds over 40 minutes).

The pattern in the Interval Table isn't random — the faster something moves across the frame, the shorter your interval needs to be to keep the motion looking smooth instead of jumpy.

The calculator's Total memory usage result accounts for your image size setting, so you know exactly how much card space (and battery) to plan for before committing to a long event duration.

You've already met this Timer in the Exposure, Star Trails, and Spot Stars lessons — it's the same tool everywhere. Start it once your interval shooting begins and it counts down the full event duration, so you know exactly when to pack up.

Say you want a time lapse of fast-moving clouds over the mountains for a club meeting presentation.