Tips about How to Choose and Use Compass

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    11-Mar-2016

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A compass helps you orient the map, identify features and pinpoint your position. True, you may hike for days on a trail and never even look at it, yet if you take a wrong turn or a whiteout blows in, a compass (in tandem with a map) suddenly becomes one of the most important tools in your pack.

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Tips about How to Choose and Use CompassIf you love outdoor sporting, then you will know compass is one of the outdoor products to help you in the journey.

A compass helps you orient the map, identify features and pinpoint your position. True, you may hike for days on a trail and never even look at it, yet if you take a wrong turn or a whiteout blows in, a compass (in tandem with a map) suddenly becomes one of the most important tools in your pack.

A compass is one of the Ten Essentials, a crucial piece of equipment you should carry on any outdoor adventure. Compasses vary widely in features and cost, however, from minimalist $10 models to high-end versions that can approach $100 or more. To help you navigate the optionsand select the compass that's right for youconsider these pointers on design, features, and functions.

The compass is your second most important navigation tool, but it is also the most important to get exactly right. Unfortunately, there's not much room for DIY here.

Your compass should have specific features, and they're absolutely worth a few bucks extra.

It should have:

1.A clear base plate- To see underneath the compass.

2. A sighting mirror- To sight objects at eye-level.

3. A rotating bezel, marked with 360 degrees in 2 degree increments.

4. Meridian lines- For map use.

5. Declination Adjustment and arrow- to correct for the difference between magnetic and true north.

And there are many more features. Just be sure you at least have the basics.

Basic compass types

A base plate compass features a free-spinning magnetized needle inside a rotating dial, or bezel, that is mounted to a flat piece of hard plastic (the base plate). It is the most usefuland recommendeddesign for backcountry navigation, especially for plotting directions to or from a map. A digital compass is often incorporated into GPS units, altimeter watches, and other handheld and wristtop devices. Though useful for general orientation, digital compasses aren't designed for hands-on map work and depend on battery power to function. Coin-sized accessory compasses can be found on keychains, watches, and other tiny items; they are useful for rough directions but not much more.

A rough orientation

Any compass, even the most inexpensive, will indicate the general direction north when held level and away from large metal objects and power lines (which interfere with the local magnetic field). In many cases, just this rough approximation will provide the information you need to make appropriate navigation decisions. Keep in mind, however, that compasses do not point due north. They point instead to the magnetic north pole, which is currently located in northern Canada. The difference between "true" north and "magnetic" northknown as the magnetic declination or variationvaries anywhere from zero degrees to 30 degrees or more, depending on your location. (In the Northeast, declination ranges from approximately 10 to 20 degrees.)

Ferrous metal can distort a compass reading, so be sure to take bearings away from your car, camera or other metallic objects. Magnetic interference can easily alter a compass reading enough to mislead you. So, if you are plotting bearings at a picnic table, check to see if your compass is being exposed to metal bolts or brackets that may affect its accuracy. Electrical fields (a running car engine, for example) can also throw off the accuracy of a compass (true for both floating-needle and digital compasses).

Be careful where you store a compass. For example, do not store a compass on top of a stereo speaker, which is equipped with a powerful magnet, or a place exposed to strong electric current. Do not place it in your pocket next to your cell phone. Over time, such exposure could demagnetize the needle. A compass responds to the dominant magnetic fields in its vicinity; you want it to be the earth's.

Be aware of regional magnetic zones. Compasses not only need to be held level to "swing" properly, they need to be appropriate for the latitude. In general, the earth has 5 different magnetic "dip" zones. These areas can cause a compass needle to drag against the housing, affecting the accuracy of a bearing. Fortunately, the contiguous United States all falls within the same magnetic dip zone.