Manual Table Of Contents
- Design Philosophy
- Quick Start
- Location Details
- Settings
- Components
- Additional Information
- Advanced
Overview
The Ephemeris feature shows sun and moon positions throughout the day for any location. Perfect for planning sunrise/sunset shoots or moonrise photography.
What is Ephemeris?
Ephemeris calculates where the sun and moon appear in the sky at any given time. For photographers, this means:
- Sunrise/sunset times – Plan golden hour shoots
- Sun position – Know where light comes from
- Moonrise/moonset – Plan night photography
- Moon phase – Full moon, crescent, new moon
Using Ephemeris
Accessing Sun/Moon Data
- Open a location from the map
- Tap Ephemeris or sun/moon icon
- View sun and moon positions for today
What You See
Sun Information
- Sunrise and sunset times
- Current sun position (azimuth and altitude)
- Civil/nautical/astronomical twilight times
- Golden hour and blue hour periods
Moon Information
- Moonrise and moonset times
- Current moon position
- Moon phase (with visual indicator)
- Illumination percentage
Time Slider
- Drag to see sun/moon positions at different times
- Visualize where light will be throughout the day
- Plan shooting times based on sun direction
Sun Rays (Home Screen)
Sun Rays appear on location thumbnails on your home screen, showing the direction of sunlight at sunrise/sunset.
What are Sun Rays?
Small arrows on each location card indicate sun direction:
- ↑ Up arrow – Sun behind you (backlit subject at this time)
- ↓ Down arrow – Sun in front/above subject (front lit at this time)
How it Works
GeoLog calculates sun position relative to where you took the photo:
- Uses the photo’s GPS coordinates
- Considers the camera heading (direction you were facing)
- Shows whether sun rises/sets behind you or in front of you
Enable Sun Rays
Settings → Display → Show Sun Rays
Toggle on to see sun direction arrows on the home screen.
Planning Shoots with Ephemeris
Golden Hour Planning
- Open your location
- Check Ephemeris for sunrise/sunset times
- Note the sun’s azimuth (compass direction)
- Plan to arrive 30 minutes early
Golden Hour Windows:
- Morning: 30 minutes after sunrise
- Evening: 30 minutes before sunset
Moonrise Photography
- Check moon phase (full moon is best for moonrise shots)
- Note moonrise time and direction
- Arrive early to set up
- Moon appears where azimuth indicates
Landscape Direction
The Ephemeris shows sun azimuth (compass direction):
- 90° – Sun rises in east
- 180° – Sun due south at noon
- 270° – Sun sets in west
Match this with your location’s heading to know where light comes from relative to your composition.
Sun Rays Details
Reading the Arrows
Sunrise arrows:
If you return to this location at sunrise:
- ↑ Up arrow = sun will be behind you (backlit scene)
- ↓ Down arrow = sun will be in front of you (front lit scene)
Sunset arrows:
Same logic applies for sunset timing.
Why This Matters
Knowing sun direction helps you:
- Plan for backlit vs front-lit subjects
- Avoid shooting into the sun (unless that’s your goal)
- Schedule visits for optimal lighting
- Return to locations at the right time of day
Example
You photographed a mountain at location X, facing west:
- Sunrise arrow shows ↓ (down) = sun rises behind the mountain
- Sunset arrow shows ↑ (up) = sun sets behind you, lighting up the mountain
- Best time: Sunset for front-lit mountain shots
Tips
Planning Shoots:
- Check Ephemeris the day before
- Account for travel time to location
- Golden hour is brief—arrive early
- Weather apps complement sun/moon data
Moonrise Shots:
- Full moon rises at sunset (look east)
- New moon is invisible
- Crescent moon visible near sun
- Moon phases cycle every 29.5 days
Using Sun Rays:
- Quick glance shows optimal time to return
- Filter locations by sun direction preference
- Plan multi-location shoots in sequence
Accuracy:
- Calculations accurate to within a few minutes
- Atmospheric refraction can affect visible sunrise/sunset by ~2 minutes
- Horizon obstructions (mountains, buildings) change apparent times
Settings
Customize Ephemeris display:
- Time Format – 12-hour or 24-hour
- Twilight Display – Show/hide twilight periods
- Sun Rays – Enable on home screen
Related Features
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