Guide

How to use Where the Sun Sets

Turn sky geometry into a practical astronomy-photography plan.

From an astronomy target to a field decision

01Choose the targetSun, Moon, twilight, Milky Way, meteor shower or star trails.
02Set place and date semanticsViewer / Planner calculate UTC calendar days; event clock times use the device time zone.
03Read azimuth + altitudeDirection alone is not enough: check where the object sits above or below the horizon.
04Check natural lightCompare solar altitude, twilight stage, Moon altitude and Moon interference.
05Choose composition + a starting pointUse focal length, field of view and exposure lessons as a starting range, not a universal setting.
06Verify on locationOpen Field Mode to re-check live direction, GPS position, nearby events and device heading when supported.

Understand the geometry behind the shot

Use the foundation lessons when the direction, phase or light itself is the question. Then return to Viewer or Planner with a physical model for what is moving and why.

Planning the night sky

For twilight, the Milky Way or meteor showers, start with time and observing coordinates, then check solar altitude, darkness and Moon interference before choosing focal length and exposure.

Location and privacy

GPS coordinates are processed in your browser to set or verify the shooting position and are not sent to Where The Sun Sets servers. When the map is displayed or moved, map-tile requests are sent to the map provider, which can infer the approximate area being viewed from those requests.

Map, Sky Path and Planner do different jobs

Map shows ground bearings. Sky Path shows the Sun and Moon above the horizon. Planner compares an observer-to-target bearing with rise/set bearings. A bearing match is not a complete 3D line-of-sight or terrain-visibility solution.

What is a bearing?

Bearings start at north (0°) and increase clockwise: east 90°, south 180°, west 270°. The colored map rays show the bearing of each rise/set event.

Golden hour and blue hour

Golden hour happens while the sun is low and light is soft and directional. Blue hour is around twilight before sunrise or after sunset. These times are useful planning references, but weather and terrain still matter.

How do I plan a sun/moon landmark shot?

In Planner, set the observer to your camera position and the target to a landmark. The app calculates the target bearing and scans future sunrise, sunset, moonrise or moonset bearings for close matches.

Use Field Mode on location

Field Mode turns the plan into a live cockpit: current Sun/Moon sky summary, target bearing, nearby rise/set events, GPS position and device heading when the browser provides them. Unsupported sensors degrade gracefully; the astronomy plan remains usable.

For meteor showers, ZHR is an idealized radiant-rate measure, not the number your camera will record per hour. Exposure and focal-length values in Learn are starting ranges; verify stars, histogram, foreground and tracking on site.

Important limitation

The app does not include DEM terrain, 3D buildings or weather. A bearing match is a candidate, not a guarantee of visibility. Check weather, elevation, obstructions and lens choice before shooting.