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Sorry if this topic has been posted already. Can anyone provide some good general information regarding compasses?

 

Specifically, I want to know how helpful it is to use a compass during geocaching? Is it better to have one that shows true North or magnetic North?

Can anyone recommend a good model for a beginner?

 

Much thanks for the information!

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A Silva Landmark will cost you about 20 bucks at Wal-mart. I learned early on not to trust cheap ones.

 

As for electronic compasses - you'll get different opinions. I prefer a good ol' magnetic compass. No batteries, no recalibrating and it's Y3K compliant.....er...maybe. :P

 

With a magnetic compass it's important that you know the declination in your particular area. Check out the discussion HERE for some great links.

 

I use a compass on just about every cache hunt that takes me into the woods and even a few of the urban micros I hit. I've always found it to be very helpful.

 

When you get into the woods under a lot of tree cover and start moving slow, you'll notice the arrow on your GPS's navigation screen will start pointing all different directions. I use my compass to re-align my GPS with north (basically turning the GPS in my hand until the "N" on the GPS is pointing the same direction as the arrow on my compass) then follow the GPS arrow ...usually right to the cache. Works like a charm.

 

Of course, this is only relevant if your GPS doesn't come with an electronic compass build in....mine doesn't.

 

Bret

Edited by CYBret
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The best deal for a beginner if you would like one that will show true norht or magnetic north would be from Brunton, most all of the Brunton Compass's will have adjustable declinatin, Suunto and Silva will also offer adjustabe declination but at a much higher price. The Silva Compasses that are sold in the USA are made by Suunto. It would be a good idea to carry a compass and a topo map of the area you are going to be in for a back up if somethng should happen to your GPS.

 

There are some geocaches that require you to use a compass heading to find the cache. There are not many of them though. A compass screen on a GPS may work fine but it can be hard to get a real accurate degree reading, and unless the GPS has an electronic compass in it the compass will not work unless you are moving.

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A compass can always be helpful while Caching, particularly when you get closer to the cache site. They can be found at most sporting goods stores from about $20 to $200. Suunto, Silva, & Brunton are three excellent manufacturers that come to mind, but there are others.

 

Most handheld compasses with a floating magnetic needle point to magnetic north. The difference between True & Magnetic north is called 'declination' and it changes with the latitude and longitude. You'll need to know what it is in order to use the GPSr (which usually shows true north) with a magnetic compass. A USGS quad map will show you the declination for your area.

 

Hope this helps.

 

- Kewaneh

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No, you don't need a compass to find most caches. However, I feel that map and compass skills are very important to keep honed if planning outdoor adventures. And a compass is necessary for some offset/puzzle/multi caches. If your GPS doesn't have an actual compass, you'll definitely want to buy a magnetic compass to carry along.

 

An excellent basic compass is the Suunto M-3 Leader. I've used the M-3 to field map hundreds (thousands?) of archaeological sites. Some info: declination adjustment screw, smooth action, very durable, easy to use, and the numbers are etched in rather than merely painted on. If you need more precision than this, you should be shopping for professional survey equipment.

 

Forestry Suppliers sells the M-3 Leader for $20, the same price local sporting good stores charge for 'toy' compasses.

 

Best Wishes,

Bob

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I'd second CYBret. I use my Silva compass at all time with my GPSr (not only for geocaching). Indeed, often when close to ground zero the GPSr goes "nuts" and the compass comes handy to triangulate the position (especially for micros). I would recommend grabbing a book of two at your local library. The “GPS for dummies” or “Geocaching for idiot’s” books are well written and go other the triangulation technique, and there are some good small navigation guides out there. You should buy a compass that allows changing the declination; the declination will be indicated on the map you use. Be careful to change your GPSr to true north if you use a map and declination. If you don't use a map you should stick with magnetic north. That is a personal choice but I would rather buy a good compass with a mirror, they are more precise. I use the ancestor of the Silva Ultra 530 that I have for about 10 years (prove to be excellent quality). Not sure how much they retail today, probably around 50$ or 60$.

 

Some prefer the electronic compass on their GPSr, but they have 3 big problems:

 

1. they eat the batteries like crazy (and if you are out of batteries, you can always find your way with the magnetic compass or at least get out of the woods).

2. they are less handy for triangulation (no mirror)

3. they don’t have scales, useful with maps.

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Sorry if this topic has been posted already.  Can anyone provide some good general information regarding compasses?

 

Specifically, I want to know how helpful it is to use a compass during geocaching?  Is it better to have one that shows true North or magnetic North?

Can anyone recommend a good model for a beginner? 

 

Much thanks for the information!

I have found a compass useful for geocaching exactly Twice in 689 caches. One time was when placing a cache that used a compass to shoot a bearing. The other time was when I needed one to do the same thing to find a cache. The time I needed it to find a cache I used the compass built into the compass page of my GPS and it worked well enough.

 

Some people swear by them. I find they may someday serve a purpose when my GPS breaks but other than that, they are dead weight.

 

As for what kind, about anything you find in the hiking section of a store is going to work well enough. Anything running about 15 and up will work. Silva is a good brand. There are other good brands. All compasses point towards magnetic north. You need to know your local declination to find True north. Which one you use depends on how you think, and work with maps. Or in Geocaching what the cache owner is thinking and how they work with maps. Hopefully they told you.

 

The reason some people find a compass handy when caching is that when a GPS gets to closer to a waypoint (the cache) than it's error (EPE) the pointer bounces around and you can't use the pointer anymore. So before they get to that point they whip out their compass use it to shoot a bearing and then walk to where that bearing pointed them at.

 

Since you can use a GPS to about 20' from a Waypoint and until that point the pointer on the GPS is accurate you can also use it to shoot a bearing and walk to where that bearing pointed you at.

 

Maybe I'm missing something but that's why I don't use a Compass and why I don't find them handy for geocaching as an activity unless the cache is specificaly designed to use a compass.

 

Edit: Having said all that I do carry a compass as standard geocaching gear and I got one specificly designed for shooting a bearing that set me back about 50 bucks. It's a silva.

Edited by Renegade Knight
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Actually, in some cases, using a compass to find a cache is indeed very helpful. If the best place you can get a satellite signal is some distance away from ground zero, then you can use the compass to triangulate the bearing from different locations and zero in on the likely hiding spot. This is especially helpful when the signal is bouncing all over the place the closer you get to the hiding location and i'm not talking a little wobble.

 

Case in point, we logged a DNF here after determining by triangulation from 25-50 feet out, where to zero in on the cache location. The nearby structure made us question our signal when we were up against it. We found the suspected spot, but were unsure due to apparent activity at the location. A confirmation call allowed us to confirm over the phone the spot we described was indeed the hiding location which looked like it was discovered by muggles and the cache gone MIA.

 

Not all stories are about DNF's though. This one had me overthinking the hide, and triangulation allowed me to zero in on the location and find the cache. The signal was very bouncy in this spot and I had to step back between 50-100 feet and triangulate the possible location resulting in a find very quickly.

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I work for a logging company, designing roads and making maps. We use silva's and some called nexus by Brunton. Any good compass should have a way to set your declination. Most compasses come with a mirror which can be used as a signalling device if one should ever get lost. I have over 15 yrs experience working in the wood and will not leave home without one. We now use a trimble for most of our surveying recording and measurents but a compass is always handy to have. One basic rule. ALWAYS TRUST YOUR COMPASS. IT DOESN'T LIE.

Have fun in the woods

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I too believe that a compass is useful, particularly when in the woods, and/or somewhere where your WAAS isn't working. As a surveyor who uses a handheld to find previous points, I find it useful once you are in the area get a good fix at a stand still and use the compass and distance shown to get closer to the point. Then repeat, or as some have mentioned you can intersect lines coming from several points in the area.

 

The point is that the compass will give you reasonably accurate bearing when you are standing still, but the GPS nav screens will be subject to vagueries of the particular reception and will not show your current direction if you are standing still or moving slowly. You usually can get a better fix in the woods if you find a good spot and stand still for a minute or so holding the GPS so that it can get the most satellites.

 

Garmin's have the option of showing true north or magnetic so that even a keychain compass can be helpful. Of course it would be better to have one that can set off declination so you don't have to switch your GPS setup around. I would guess other GPSR's have those options also.

 

Now days GPS units may display distance in fine units, but I learned using the older GPS12 types where distance resolution is at best 0.01 miles. Thus using the bearings to intersect into the specific location provides a more precise method.

 

By keychain compass, these are often given away free and have a wind chill thermo and table on them. Perhaps they are for cross country skiing.

 

Brunton 9045 TAG-A-LONG PLUS is one example. I am not recommending this as the best option, but have found that even the minimal compass is useful. And it takes no battery power to run.

 

- jlw

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