How to make a night-sky time-lapse

Choose a place where you are allowed to stay for the whole session, and check access, weather and the Moon before leaving. Keep paths clear and protect equipment from wind and dew. The sky changes with season, latitude and viewing direction, so check a sky chart for the scene you want rather than assuming the Milky Way will be visible in every direction.

A phone or camera with manual exposure, a stable support and a way to take repeated frames is a useful starting point. Some devices have a built-in interval timer; others need an app or remote. Check that yours can save each frame and that the battery and storage can cover the planned run. NASA's smartphone guide explains steady support, focus and exposure for night photographs.

Multiply the desired video length in seconds by its playback frame rate. A 10-second clip at 24 frames per second needs 240 usable photographs. Allow extra frames for testing or rejects.

If your intervalometer defines interval as the time from one exposure's start to the next, 240 frames started 22 seconds apart take approximately 88 minutes to capture. This is an estimate: the first exposure, processing and your device's interval rules affect the exact finish time. Some timers define the delay after an exposure instead. Check the manual and run a short sequence before relying on the calculation.

The start-to-start interval must allow the exposure and any time your camera needs before it can take the next frame. For example, a 20-second exposure with a 22-second start-to-start interval leaves two seconds between exposures. If processing or writing takes longer, increase the interval or change the camera settings. Longer gaps make the final motion less continuous.

1. Secure the camera or phone on a stable support. Frame the sky and foreground before starting, leaving room for the scene to change.
2. Focus on a bright, distant star or light, magnify the image if your device allows it, then lock focus. The infinity mark is a starting point, not a guarantee.
3. Set exposure and ISO manually if available. Take a test frame, inspect focus and star shape at high magnification, and adjust for the scene. Longer exposures collect more light but can also make stars trail in a fixed frame.
4. Set the interval and take a short run. Check for missed frames, camera shake and unwanted lights before committing to the full sequence.
5. Start the sequence and avoid touching the support. Check the lens for dew and the power supply during a natural pause, without shining light into other people's photographs.

There is no universal shutter speed: focal length, sensor, sky brightness and the amount of trailing you accept all matter. NASA's astrophotography guide discusses intervalometers and the trade-off between gathering light and star movement.

Copy the originals to your computer before editing. Review the sequence for blurred or missing frames, then apply consistent adjustments across the set. Import the ordered images into an editor that supports image sequences and choose the playback frame rate used in your calculation. Export a short test before processing the entire set.

If brightness changes sharply between frames, check for automatic exposure, changing light, clouds or dew. A day-to-night sequence needs exposure changes as the light falls and can flicker; begin with a fully dark sequence until your equipment and editing workflow are familiar. Keep the original files so you can try a different edit.

Use the lowest light you need to move safely and follow the site's rules. A dim red light can help preserve dark adaptation, but bright red light can still affect it. The National Park Service explains why brightness matters. Check with nearby photographers before using any light, and leave wildlife and other visitors undisturbed. Never look at or point a camera at the Sun without appropriate solar protection.

Reviewed 15 November 2026 using NASA's smartphone astrophotography article, NASA's astrophotography guide and the National Park Service's dark-adaptation guidance. Camera controls and timer definitions vary by model; consult your manual.