To ensure correct compass readings, set an accurate declination value.
Paper maps point to true north. Compasses, however, point to magnetic north – a region above the Earth where the Earth’s magnetic fields pull. Because magnetic North and true North are not at the same location, you must set the declination on your compass. The angle in between magnetic and true north is your declination.
The declination value appears on most maps. The location of magnetic north changes yearly, so the most accurate and up-to-date declination value can be obtained from the internet (for example www.magnetic-declination.com).
Orienteering maps, however, are drawn in relation to magnetic north. This means that when you are using orienteering maps you need to turn the declination correction off by setting the declination value to 0 degrees.
To set the declination value:
You can also enter the compass settings by keeping Compass mode.
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