LocationScoutCam-solar compass

This app records GPS coordinates and camera angles when taking photos and displays them on a map. 

It also includes a solar compass showing sunrise/sunset times and the sun's position. 

All features are completely free to use.

The solar compass can be shown on the map, when the camera starts, and during photo preview. 

When displayed at camera start, it helps you understand the camera angle and current sun position. 

During photo preview, you can change the date and time while keeping the latitude, longitude, and camera angle fixed. 

This allows you to investigate shadows when visiting different seasons.

Note: On the map, the direction is based on the device being level. 

During camera start and photo preview, the direction is based on the camera's position being vertical. 

If you look directly at the sun, the error may be large since the device is not vertical.

The app is optimized for location hunting and fieldwork, aiming to collect as much information as possible in one site visit.

GPS coordinates are only used to show location information while using the app. 

No information is sent to our servers. 

The app does not run in the background, so battery drain is minimal.

Additional Information on Calculations:

- Direction 

All compass and camera angles are corrected for declination based on latitude and longitude, using true north as a reference. 

The direction is the same as the iOS native compass, but it may be affected by nearby electronics like buildings and computers.

- Declination

The declination is calculated using The World Magnetic Model 2020 (WMM2020) file. 

This file provides predictions for the next five years and is valid until December 31, 2024. 

We will update to WMM2025 once it is released.

- Solar Altitude and Sunrise/Sunset Calculations

We use formulas defined by NOAA (National Oceanic and Atmospheric Administration). 

NOAA runs a web service called NOAA Solar Calculator, which calculates various values based on latitude, longitude, and time zone. 

If you are unsure about the accuracy of the values calculated by our app, please try this web service. 

(If there is a difference, it may be a mistake on our part, so please let us know!)

- Sunrise and Sunset Times

Sunrise and sunset times may differ by about one minute from the time when the sun's altitude is zero. 

This is because the sun's visual diameter is 0.53°, and sunrise/sunset is defined as when the top of the sun reaches the horizon. 

For example, if the sun's altitude is -0.46° at sunrise, adding the 0.53° visual diameter results in 0.07°, indicating correct calculation.

- Shadow Length

The number below the shadow length shows how long the shadow of a 1m stick would be. 

When the sun's altitude is close to zero, the shadow length approaches infinity, assuming no obstacles in the sun's direction. 

If you want to take photos with long shadows, check for obstacles in the sun's direction at that time.

Note on Photo Saving:

Photos are saved to the OS's photo library and linked with the app through the file name. 

If you delete photos taken with the app or rename them using another app, they will no longer be displayed in the app. Please keep this in mind.