01 · Minimal kit
Start with what you have.
- An Android phone with manual camera controls. RAW capture is ideal because it preserves more image data, but JPEG can still work.
- A rigid phone clamp and tripod. A beanbag or solid ledge can work if the phone cannot move at all.
- DeepSkyCamera installed, enough free storage, and a charged battery or power bank.
- A clear night away from direct lamps. Darker skies reveal more, but bright constellations are visible from many towns.
02 · Field setup
Make the phone absolutely still.
- Clean the main camera lens and mount the phone. Use the main 1× camera; avoid digital zoom.
- Point toward a star-rich area. Looking high above the horizon usually reduces haze and light pollution.
- Turn on airplane mode or Do Not Disturb. Disable battery optimisation for DeepSkyCamera so Android does not pause a long sequence.
- Set the display dim and use the app’s red night mode. Avoid white lights for about 20 minutes so your eyes adapt.
- Compose with the preview grid. Leave room around the constellation or Milky Way area you want to identify.
03 · DeepSkyCamera controls
Set preview and capture separately.
This is the app’s most important idea: viewfinder settings are independent from the settings used for saved photographs. A bright preview can help you aim without forcing the final RAW to use the same extreme ISO.
A reliable first-night recipe
| Control | Start here | Why |
|---|---|---|
| Preview | 1 s, very high ISO | Makes bright stars easier to see while aiming. The official manual uses ISO 12800 as an example where supported. |
| Format | RAW or RAW+JPEG | RAW preserves much more editing latitude. Choose JPEG only when RAW is unavailable. |
| Type | Lights | These are the normal sky photographs you will later stack or upload. |
| Exposure | 10–20 s untracked | Test a frame at 100% zoom. Shorten it if stars become dashes. The app’s pinpoint-star calculator can help. |
| ISO | 800, then 1600 if needed | The manual recommends staying around ISO 800 or 1600 for typical wide phone apertures. |
| Interval | 1–3 s | Gives the phone time to save large DNG files. Increase to 6 s if frames are missed. |
| Frames | 30 | Enough to practice stacking while keeping the first session manageable. |
| White balance | 3800–4300 K | A consistent neutral starting point; RAW allows later adjustment. |
| Focus | Infinity, then refine | Zoom the preview on a bright star and adjust until it is smallest and crispest. |
- Open the lower image-settings bar with the triangle above the shutter control.
- Choose RAW, Type: Lights, then exposure, ISO, interval, and number of frames.
- Set manual or customised infinity focus. Do not trust autofocus in a dark, empty frame.
- In Settings, enable night mode and “display always on” if your phone tends to sleep.
- If you will stack with dark frames, leave in-app hot-pixel removal off. Otherwise, High Quality is reasonable for a single slow exposure when supported.
- Add a 5–10 second start delay, tap the shutter, and do not touch the tripod.
04 · Capture sequence
Build the result from a clean sequence.
- Take one test exposure and zoom into stars. Correct focus first; then shorten exposure if trails appear.
- Check the histogram. Keep the sky background away from both the extreme left edge and the bright half of the graph.
- Run 20–50 light frames without moving the phone. A sequence of 30 × 15 seconds gives 7.5 minutes of total light.
- Watch for dew, tripod movement, passing clouds, aircraft, and nearby headlights.
- Before packing up, capture calibration frames while the sensor is still near the same temperature.
Large modern sensors can produce very large RAW files. If the app loses frames, allow a longer interval and use fast internal storage or a suitable high-speed card.
05 · Darks and stacking
Capture calibration frames for cleaner stacking.
For dark frames, cover the lens completely and keep the same ISO and exposure time as the lights. Capture 10–20 without changing the phone’s temperature more than necessary. Darks help identify hot pixels and fixed-pattern noise.
Bias frames use the fastest shutter speed with the lens covered. Flats help correct vignetting and dust but require an evenly illuminated surface and are optional for a first wide-field phone session.
Stacking aligns the stars across many lights and combines their signal. NightTrace currently accepts one source photo per upload. Support for full multi-frame light and calibration sets can be added later.
06 · NightTrace
Send the original pixels.
Upload the original RAW file rather than a social-media copy. Add the capture time, location, direction, phone, exposure, and ISO when you know them. NightTrace primarily identifies the sky from the star pattern, while good capture details can make difficult photographs easier to match and verify.
Primary reference: DeepSkyCamera Free 2.1.7 manual, January 2026.