Monday, July 12, 2010

Compass Use For Newbies

By JJ Smith

The most commonly used type of compass for outdoor recreation is called a protractor, orienteering , or baseplate compass. These compasses usually have a clear plastic baseplate, a magnetic needle, and a dial that can be twisted to set the compass. Other types of compasses include lensatic and pocket compasses. These work a little differently, and will not be covered in this article, which focuses only on the baseplate type of compass.

Holding the Compass Properly: Hold the compass flat and level, but elevated high enough so that you can read the compass direction while glancing up to look at objects in the distance. Orient the compass so that the direction of travel indicator, at the top of the compass dial, is facing directly away from you. Having the lanyard around your neck will help you keep the compass oriented perfectly with the direction you are facing.

Next, learn what the magnetic needle does. There are some technical nuances about magnetism, but at the basic level of operation there is only one thing you need to remember: The red end of the needle ALWAYS POINTS NORTH. Once you drill this fact into your mind you'll need to understand that there is more than one NORTH. The magnetic needle actually points toward the Magnetic North Pole, which is in a slightly different location than the geographic or "true" North Pole that maps are based on. The distinction is only important if you are using a map along with your compass. If this is the case, which it most often is, you will have to learn how to make a correction in your compass reading to account for the difference between magnetic north and true north (this is called magnetic declination).

Sighting the Compass: Face in the direction you would like to determine maybe this is a direction in which you can see a landscape feature like a hill or perhaps it is just a straight section of a path you plan to hike. Carefully line up the direction of travel indicator (and your body) with the object or direction you wish to travel. Look at the object then glance down at the compass repeatedly and make adjustments to the way your body is facing until the object is directly in line with the direction of travel indicator.

Now, set the compass: Holding the compass still in the direction you sighted, twist the dial until the hollow orientation arrow lines up beneath the needle. When the needle is "boxed" in this manner, the compass is set.

Finally, read the Compass: The number on the compass dial that lines up with the direction of travel indicator at the top (front) of the compass dial is your direction, also called your bearing. It can be expressed in a number of ways including the quadrant or azimuth method depending on the type of compass you have. The azimuth method is easiest. It is a single number between 0-360 degrees, where 90 is East, 180 is south, 270 is west, and 360 (and 0) is north.

Practice these 5 steps until you are comfortable using bearings to navigate around your neighborhood. Learn how to adjust for magnetic declination and read a map before doing any serious or off-trail hiking.

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