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How to Use a Compass || REI



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a compass is part of the 10 essentials

and most people take one with them into

the mountains but how in the world does

it work luckily it isn't too hard to use

your compass and when paired with a good

map and a bit of know-how it becomes a

powerful tool for navigation in this

video we're going to cover the essential

parts of the compass how to set up your

compass to account for the declination

for your region how to take a bearing

from a map to find an object in the

field and how to take a bearing in the

field to find yourself on a map alright

it's going to be hard to talk about how

to use the compass without first

understanding what all the different

parts are for so let's go through that

real quick this is the base plate it's

clear so you can see the map below it

and there's always at least one straight

edge that you'll use later for taking

bearings on the side there are rulers

that you can use along with your map

scale to help you calculate distance

on top you'll find a direction of travel

arrow to remind you which direction to

point the compass when you're taking a

bearing this big circle is the rotating

bezel which is marked with degrees from

zero clockwise up to 360 above the bezel

is a little marker called the index line

which marks where you'll read your

bearings inside the bezel the first

thing you'll notice is the magnetized

needle which always points to the

magnetic north pole not the true North

Pole we'll get into the difference in a

minute there's also a big arrow called

the orienting arrow which we'll use to

help you orient the bezel alongside the

orienting arrow our orienting lines that

you'll use to help you line up the

compass with north on a map finally some

compasses have a handy declination scale

which makes it easier to adjust

declination what's declination you ask

well declination is the angle difference

between true north and magnetic north

the needle in your compass will only

point to magnetic north so right now

it's pointing to somewhere in northern

Canada not Santa's workshop if you don't

adjust your compass to account for the

difference between magnetic north and

true north

it can really mess up your navigation

depending on where you are in the

country the declination will be a

certain number of degrees to either the

west or the east

you can find the direction a number of

degrees in the declination diagram near

the legend along with the date of the

maps most recent revision if your map

hasn't been revised for several years

it's worth looking up the current

declination online different compass

brands set declination in different ways

and once you know the declination for

your region you can put that information

into your compass when you do and the

needle lines up inside the orienting

arrow the north marker on the bezel will

point to true north this map of the Lake

Tahoe area has a declination of 14

degrees east and it was updated very

recently so we need to move the

orienting arrow 14 degrees to the east

now that the declination is set you can

start using your compass with your map

first off a bearing describes a

direction in terms of degrees bearings

are way more precise than just saying go

east or west instead you can say to get

to the lake follow a bearing of 79

degrees one of the most common way is to

use the bearing is when you're out

hiking and you want to head to a

specific point like a peak or your

campsite if you know where you are on a

map it's a simple process start by

finding your current location on the map

let's say were here now set your compass

on the map so that the straight side of

the baseplate lines up with your

position next find the point you want to

head toward let's say it's this peak and

rotate the entire compass until it forms

a line between your position and your

destination

make sure the direction of travel arrow

is pointing in the direction of the peak

once the compass is in position rotate

the bezel until the orienting lines are

lined up with north and south on the map

you can use the edge of the map to help

you get the lines position just right

remember to make sure that the North

marker on the bezel is pointing to north

on the map and not south okay once the

orienting lines are running north-south

look at the index line to read the

bearing you've just captured here it's

188

Congrats now you can use the compass to

follow the bearing pull the compass in

front of you with the direction of

travel arrow pointing away from you now

rotate your whole body until the north

side of the magnetized needle is inside

the orienting arrow if it helps you can

remember red in the shed once you've got

red in the shed you're facing the

bearing of 188 and your destination if

you're out hiking and you want to find

your location on a map you can also take

a bearing off a landmark near you then

you can transfer that bearing to your

map and figure out where you are start

by finding a landmark that you can also

identify on your map hold your compass

up with the direction of travel arrow

pointing away from you and directly at

the landmark now keep the compass flat

and rotate the bezel until the

magnetized needle is inside the

orienting arrow or red is in the shed

once the needle is in you've captured

the bearing a compass with a sighting

near makes it easy to take very accurate

bearings hold the compass at eye level

and point it at the object then tilt the

mirror until you can see straight down

into the bezel this way you can see the

object and the bezel at the same time

once you've got the bearing you can

transfer it to the map lay your compass

on the map and line up its edge with a

known landmark make sure that the

direction of travel arrow is pointing in

the direction of the landmark with the

edge of the compass lined up against the

object rotate the entire baseplate until

the orienting lines are running

north-south and the North marker on the

bezel is pointing to North on the map

once you've finished you can draw a line

on the map along the edge of your

compass you are somewhere along this

line if you want to find your exact

position you use the process called

triangulation all you have to do is take

another bearing but with a different

object that's at least sixty degrees

away from the first where the two lines

intersect is your position

if you take a third bearing you'll end

up with a little triangle and the

smaller the triangle the more accurate

the reading compass skills can be

daunting at first but they get way

easier with practice watch the video a

few times to get familiar with the

techniques and then test them out on

your favorite Trail and for more

practice and a deeper dive into

navigation click here to find a

navigation class near you