# Questions tagged [true-north]

The direction to the geographic north pole.

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### EXIF: Can you calculate latitude from longitude value and true north value?

I have an iPhone image that contains the GPS longitude and a bearing relative to True North. Is it possible to calculate the latitude from these two values? EXIF metadata in question: GPS Longitude ...
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### How to interpret GPSDestBearing and GPSImgDirection?

I need to take some photos capturing the GPS coords and direction of camera. I'm using an iPhone 8+ and this is the relevant output I get from Acute Photo EXIF Viewer: EXIF GPS Tags GPSDestBearing:...
• 73
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### True-North Bearing between two GPS coordinates

I am trying to find the correct equation to find the bearing off of true-north between two GPS coordinates. I have seen a lot of online calculators and a lot of formulas on this GIS stack exchange, ...
• 171
526 views

### Calculating convergence angle for point data in QGIS

I have been a user of ArcGIS Desktop for many years and this function is easily done within ArcMap using the 'Calculate Grid Convergence Angle (Cartography)' tool. I am wondering if there is a ...
• 41
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### How is ST_Azimuth (in PostGIS) calculated?

What algorithms are internally calculated in PostGIS? Can you explain it with simple code? (I want to know the standard of true north.)
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### Using azimuths and bearings in GeographicLib? [closed]

I am currently using the JavaScript port of the geodesic routines from GeographicLib: https://geographiclib.sourceforge.io/html/js/ https://github.com/yurijmikhalevich/node-geographiclib I am ...
• 3
687 views

### How can I find the average bearing using a set of zig-zaggy coordinates, knowing the user travelled in a straight line during that period?

Some background: I'm developing an app which uses augmented reality and GPS data in order to improve the True North accuracy of the device. Currently, iPhones have a True North accuracy of about 15º ...
• 131
1 vote
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### meridian convergence local coordinate systems [duplicate]

I am new to the concept of meridian convergence. I understand that it is the angle between True North and Grid North. But I have problems understanding how meridian convergence affects local ...
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### How can I rotate a map layer in QGIS so that center of map always have north upwards?

I'm working in the polar regions and make maps in different scales. The convention is to show e.g. the Antarctic continent with the prime meridian upwards on the map and polar stereographic projection....
• 368
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### Does Magnetic Deviation depend on altitude? [closed]

Magnetic declination, sometimes called magnetic variation, is the angle between magnetic north and true north. Declination is positive east of true north and negative when west. Magnetic ...