How to Use a Lensatic Compass
- 1). Determine your local declination angle. This is the angle between true north and magnetic north. The declination angle varies by location and is usually provided by a recent map of your area. For example, a declination angle of 5 degrees means that magnetic north is 5 degrees clockwise from true north.
- 2). Set your compass needle to point to true north. A lensatic compass typically allows you to rotate the compass needle to true north and lock it so that it always points to true north. If the declination angle is 5 degrees, you would turn the needle 5 degrees counterclockwise and lock it.
- 3). Lay the map on a flat surface and completely unfold the lensatic compass. Put the compass on the map so that the long side is parallel with the north/south gridline of the map.
- 4). Hold the map and compass so they can move together without slipping. Rotate the map and compass carefully until the needle is pointing at 0 degrees. Your map is now oriented toward true north.
- 5). Line up the compass to point to your desired destination and note the compass reading. This indicates the heading you need to maintain to reach your destination.
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