What's your favorite type of compass
- Thread starter budman
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While Budman is asking questions re compass types, I would like to know what the small combo unit appearing compass that Ron shows in his Navigation tape.
Secondly, Suunto,http://www.suunto.fi/field/index.html
offers a global capsule compass. Is this better, and if so why? Supposedly, it is more useful around the world, as opposed to a normal compass. Can anyone explain this? Has anyone used their compass that is supposed to be a companion to a GPS unit? In other words, it is big, is it worth it?
Thirdly, if anyone can and will answer these questions I may not need it
, but are there any mini-treatises on the web or elsewhere about the principles of good compass use. I need a refresher course, especially when I realize I do not even know how to differentiate among the types of compasses. Any recommended longer works on compass use?
Thanks.
Secondly, Suunto,http://www.suunto.fi/field/index.html
offers a global capsule compass. Is this better, and if so why? Supposedly, it is more useful around the world, as opposed to a normal compass. Can anyone explain this? Has anyone used their compass that is supposed to be a companion to a GPS unit? In other words, it is big, is it worth it?
Thirdly, if anyone can and will answer these questions I may not need it
Thanks.
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The silva Ranger is small compact and allows you to set the magnetic variation for your location. I like the concept and it has served many of my students well. Personally, I carry a cheap $7 silva. It works great.
The compass is simply a tool and the trick is...knowing how to use it.
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Greg Davenport
http://www.ssurvival.com
Are You Ready For The Challenge?
Are You Ready To Learn The Art Of Wilderness Survival?
The compass is simply a tool and the trick is...knowing how to use it.
------------------
Greg Davenport
http://www.ssurvival.com
Are You Ready For The Challenge?
Are You Ready To Learn The Art Of Wilderness Survival?
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You don't have to spend a lot for such a simple device, but if you want one of the best, get a military issue Stocker & Yale compass (around $50). It's made of real metal, has glow in the dark marks, and is rock solid.
The compass in the video you mentioned is a silva with a thermometer. I picked a few up at a swap meet.
The GPS shows you where you are but not the direction you are facing. Not long ago I was on a SAR, it was snowing, I had my Magellan GPS and map. I located my position on the map with the GPS and noted a small building on the map appeared to be about 1/4 mile away almost due North of my position. With the compass I made my way to the cabin... That would have been very difficult with just one of either instrument.
Ron
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Learn Life Extension at:
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The GPS shows you where you are but not the direction you are facing. Not long ago I was on a SAR, it was snowing, I had my Magellan GPS and map. I located my position on the map with the GPS and noted a small building on the map appeared to be about 1/4 mile away almost due North of my position. With the compass I made my way to the cabin... That would have been very difficult with just one of either instrument.
Ron
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Learn Life Extension at:
http://www.survival.com ]
Hello Greg
You mention that the Silva Ranger can compensate for local magnetic variations. Can it handle a Northern/southern hemisphere change? Are there any out there that can?
I have a Stocker an Yale that I bought when I lived in Canada. The needle is at a funny angle, and gives erroneous readings, now that I am living in New Zealand. Stocker and Yale can supply a needle assembly specifically for the southern hemisphere.
You mention that the Silva Ranger can compensate for local magnetic variations. Can it handle a Northern/southern hemisphere change? Are there any out there that can?
I have a Stocker an Yale that I bought when I lived in Canada. The needle is at a funny angle, and gives erroneous readings, now that I am living in New Zealand. Stocker and Yale can supply a needle assembly specifically for the southern hemisphere.
pso,
Maybe I'm a complete idiot but that's a new one on me, or maybe I didn't understand the question.
I've used a cheap silva below the euqator many times and it's always read true. North has always been north.
This can be verified with GPS if you're moving in a car or boat, since GPS will give you direction of travel efficiently while your moving. - Jeff
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Randall's Adventure & Training
jeff@jungletraining.com
Maybe I'm a complete idiot but that's a new one on me, or maybe I didn't understand the question.
I've used a cheap silva below the euqator many times and it's always read true. North has always been north.
This can be verified with GPS if you're moving in a car or boat, since GPS will give you direction of travel efficiently while your moving. - Jeff
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Randall's Adventure & Training
jeff@jungletraining.com
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pso
Compasses are subject to errors from both magnetic inclination and declination. Most compasses for navigation have an adjustment for declination. Manufacturers such as Suunto and Silva sell versions of their compasses with different counterweighting for different latitudes (to address inclination). Some models such as International versions of the Brunton Pocket Transit Compass are available in versions that have more sophisticated mechanisms whose accuracy is not degraded by the typical magnetic inclination virtually everywhere on the earth's surface. More info on the subject can be found at http://www.cam.org/~gouletc/decl_faq.html
[This message has been edited by Alan_B (edited 02 December 1999).]
Compasses are subject to errors from both magnetic inclination and declination. Most compasses for navigation have an adjustment for declination. Manufacturers such as Suunto and Silva sell versions of their compasses with different counterweighting for different latitudes (to address inclination). Some models such as International versions of the Brunton Pocket Transit Compass are available in versions that have more sophisticated mechanisms whose accuracy is not degraded by the typical magnetic inclination virtually everywhere on the earth's surface. More info on the subject can be found at http://www.cam.org/~gouletc/decl_faq.html
[This message has been edited by Alan_B (edited 02 December 1999).]
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Allen_B, I believe you have answered my question. Thanks. (Do I have to publically admit that I have not yet quite comprehended the answer?....nah)
pso, Certain Suunto models have a global capsule which are supposed to make the compass world friendly and thus not impacted by whatever Allen_B was talking about. In other worlds, this avoids having to have a compass optimized for a certain locale.
Put somewhat more pleonastically: What I recall and all I found out a few months ago, is the following: In a normal compass the needle is magnetized. In a globally adept compass for use anywhere in the world, the magnet is separate from the needle. This global capsule better takes into account worldwide variations whereas normal compasses are optimized for the location where they are sold. This is (I think....maybe???) a different concept than just magnetic deviation from true north. Oh yes, I was told that global capsule compasses also react more smoothly and quickly.
The global capsule is supposed to be generally better and costs a couple of bucks more. I have no idea who makes what models that would be "enhanced," only that the Suunto GPS companion compass comes in both types.
Donald
Miami, FL
pso, Certain Suunto models have a global capsule which are supposed to make the compass world friendly and thus not impacted by whatever Allen_B was talking about. In other worlds, this avoids having to have a compass optimized for a certain locale.
Put somewhat more pleonastically: What I recall and all I found out a few months ago, is the following: In a normal compass the needle is magnetized. In a globally adept compass for use anywhere in the world, the magnet is separate from the needle. This global capsule better takes into account worldwide variations whereas normal compasses are optimized for the location where they are sold. This is (I think....maybe???) a different concept than just magnetic deviation from true north. Oh yes, I was told that global capsule compasses also react more smoothly and quickly.
The global capsule is supposed to be generally better and costs a couple of bucks more. I have no idea who makes what models that would be "enhanced," only that the Suunto GPS companion compass comes in both types.
Donald
Miami, FL
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Donald,
I can't claim any expertise about this compass stuff but here is my simple interpretation. As you move latutides (north and south) the compass needle is pulled vertically by the earth's magnetic field a different amount. Since the compass is presuably most accurate when the needle is level, I would expect that this could lead to some error. I don't know how big the errors can get with typical compasses but my guess is that unless you are very near the poles or require an exceedingly accurate bearing the issue is moot.
My Brunton Pocket Transit is an international model designed to work in both the Northern and Southern hemispheres even though I've never used it anywhere but in North America. My limited experience is that the dampening on this instrument is greatly inferior to that on the standard version of the same instrument that I have used and the international version cost another ten bucks or so.
Returning to the original question about favorite compasses, I would have to say that my favorite highly depends on the task at hand. For example, I am a big fan of the Suunto sighting compasses and inclinometers (typically enclosed in aluminum cases and with models number like KB-14 or something). These compasses are very easy for shooting bearings to landmarks. I've even found them easy to use from a small boat in fairly choppy water. The downside of these compasses is that they don't have the clear base that makes it easy to relate maps directly to the terrain (although a small clear plastic ruler with a built in protractor works well).
If you do use a GPS and quad maps you may want to consider one of the Suunto or Silva models designed specifically for plotting GPS data on maps. Cheers! -Alan
I can't claim any expertise about this compass stuff but here is my simple interpretation. As you move latutides (north and south) the compass needle is pulled vertically by the earth's magnetic field a different amount. Since the compass is presuably most accurate when the needle is level, I would expect that this could lead to some error. I don't know how big the errors can get with typical compasses but my guess is that unless you are very near the poles or require an exceedingly accurate bearing the issue is moot.
My Brunton Pocket Transit is an international model designed to work in both the Northern and Southern hemispheres even though I've never used it anywhere but in North America. My limited experience is that the dampening on this instrument is greatly inferior to that on the standard version of the same instrument that I have used and the international version cost another ten bucks or so.
Returning to the original question about favorite compasses, I would have to say that my favorite highly depends on the task at hand. For example, I am a big fan of the Suunto sighting compasses and inclinometers (typically enclosed in aluminum cases and with models number like KB-14 or something). These compasses are very easy for shooting bearings to landmarks. I've even found them easy to use from a small boat in fairly choppy water. The downside of these compasses is that they don't have the clear base that makes it easy to relate maps directly to the terrain (although a small clear plastic ruler with a built in protractor works well).
If you do use a GPS and quad maps you may want to consider one of the Suunto or Silva models designed specifically for plotting GPS data on maps. Cheers! -Alan
If you look at the FAQ mentioned above, you can see that a compass can show more than 40 degrees wrong, if you use it in a place it wasn't made for. Perhaps good enough for finding a coast, river or road, escecially if you're lost and don't know precisely where you are anyway. But not very useful if you're trying to find a spot from a known location.
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Urban Fredriksson
www.canit.se/%7Egriffon/
"Smooth and serrated blades cut in two entirely different fashions."
- The Teeth of the Tyrannosaurs, Scientific American, Sep 1999
40 degrees is considerable - the difference between going north and northeast.
Although I uderstand the problems associated with compasses the closer you get to the poles, my personal experince has found that most compasses give fairly accurate readings just about anywhere (never been to the poles), given your not in a cave, or around some other geographic structure causing severe deviation.
Again, if you want to check your compass, then compare it to a GPS (options set for magnetic north) when traveling. - Jeff
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Randall's Adventure & Training
jeff@jungletraining.com
Although I uderstand the problems associated with compasses the closer you get to the poles, my personal experince has found that most compasses give fairly accurate readings just about anywhere (never been to the poles), given your not in a cave, or around some other geographic structure causing severe deviation.
Again, if you want to check your compass, then compare it to a GPS (options set for magnetic north) when traveling. - Jeff
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Randall's Adventure & Training
jeff@jungletraining.com
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Compass tip (now don't get excited this is just something I recently found useful.)
Background: I purchased the Spyderco Mini-Police Necklace. The chain was too short to pull it over my head and use the knife. I went looking for a 28" sterling silver chain, but the longest I could find was a 24" sterling silver ball chain which worked, just not as perfectly as a 28" chain. The cost was about $13. (My wife will not part with her 28" chain
) I also recently bought an inexpensive Suunto mini compass/thermometer which has a split ring on it, I suppose similar to the one Ron used in his video.
The point: I went hiking around in the Everglades National Park and took the compass on the 24" sterling silver ball chain. When I wanted to verify a direction I just pulled up the compass and it worked fine.
Obviously any non-magnetic chain or lanyard such as paracord would work, but hey I had it. Since a lot of the larger compasses come with their own lanyard this is probably too obvious for most of this group
Hmmm...so how do I justify it...now that I have typed this...oh yeah...parts of the glistening chain could be used for flash in improvised fishing lures or for trading purposes on those jungle trips.
[This message has been edited by Donald (edited 03 December 1999).]
Background: I purchased the Spyderco Mini-Police Necklace. The chain was too short to pull it over my head and use the knife. I went looking for a 28" sterling silver chain, but the longest I could find was a 24" sterling silver ball chain which worked, just not as perfectly as a 28" chain. The cost was about $13. (My wife will not part with her 28" chain
The point: I went hiking around in the Everglades National Park and took the compass on the 24" sterling silver ball chain. When I wanted to verify a direction I just pulled up the compass and it worked fine.
Obviously any non-magnetic chain or lanyard such as paracord would work, but hey I had it. Since a lot of the larger compasses come with their own lanyard this is probably too obvious for most of this group
[This message has been edited by Donald (edited 03 December 1999).]
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Donald,
I lanyard my compass with 550 to a belt loop just above my right pocket. The compass is thus safe and easily accessed from the pocket.
------------------
Greg Davenport
http://www.ssurvival.com
Are You Ready For The Challenge?
Are You Ready To Learn The Art Of Wilderness Survival?
I lanyard my compass with 550 to a belt loop just above my right pocket. The compass is thus safe and easily accessed from the pocket.
------------------
Greg Davenport
http://www.ssurvival.com
Are You Ready For The Challenge?
Are You Ready To Learn The Art Of Wilderness Survival?
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Hi everyone, just a quick question perhaps some of you compass experienced people can answer; has anybody any experience with the Brunton Eclips (I think it's called that) compass ? It uses a rotating disk with a red circle for the north and is supposed to be more foolproof, it is pakaged in a rubber like cover that also seems to hold survival cards, GPS conversion cards and so on.
I've seen a Silva compass like it in Holland that looks to be a full twin but our Dutch price is over $125 while the Brunton costs about $75 in the USA.
Any info is appreciated.
Bagheera
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I've seen a Silva compass like it in Holland that looks to be a full twin but our Dutch price is over $125 while the Brunton costs about $75 in the USA.
Any info is appreciated.
Bagheera
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Griffon,
My read of the FAQ is that error due to magnetic DECLINATION can exceed 40 degrees but that the magnitude of errors due to magnetic INCLINATION are not specified in the FAQ and may be dependent upon the particular compass design (my inference). I know that this is confusing but DECLINATION is easily accounted for with widely available info (on all USGS topo maps for U.S.). The author of the the FAQ suggests that INCLINATION can be compensated for by tilting your compass. This would be consistent with Jeff's experience that his Northern Hemisphere compass gave him fairly accurate readings south of the equator.
[This message has been edited by Alan_B (edited 03 December 1999).]
My read of the FAQ is that error due to magnetic DECLINATION can exceed 40 degrees but that the magnitude of errors due to magnetic INCLINATION are not specified in the FAQ and may be dependent upon the particular compass design (my inference). I know that this is confusing but DECLINATION is easily accounted for with widely available info (on all USGS topo maps for U.S.). The author of the the FAQ suggests that INCLINATION can be compensated for by tilting your compass. This would be consistent with Jeff's experience that his Northern Hemisphere compass gave him fairly accurate readings south of the equator.
[This message has been edited by Alan_B (edited 03 December 1999).]
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Terrific info, thanks to all. Learn from the best, or die with the rest. BTW, just ordered a Silva Ranger 15CL from Campmor @32.97. Good price? It'll go into the maxi-kit until I figure out my GPS/compass combo. How about some ideas? Magellan 410/Brunton Eclipse?or? Jason
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The silva ranger is good and afordable compass. You can't go wrong with it. Just make sure to change the declination setting when you go from one trip to the next.
Note: you could just set it at 0 and adjust the variation mathamatically.
The GPS is a good tool but not one you should rely on. It doesn't always lock in enough different sattelite (sp) to pinpoint your location and the batteries can fail due to cold soaking, etc. I will post a story that one of my former students told me this year about a rescue he performed. He is a USCG rescue swimmer (they are doing a lot of in land rescues these days). I will title it "Batteries can fail"
Best,
------------------
Greg Davenport
http://www.ssurvival.com
Are You Ready For The Challenge?
Are You Ready To Learn The Art Of Wilderness Survival?
Note: you could just set it at 0 and adjust the variation mathamatically.
The GPS is a good tool but not one you should rely on. It doesn't always lock in enough different sattelite (sp) to pinpoint your location and the batteries can fail due to cold soaking, etc. I will post a story that one of my former students told me this year about a rescue he performed. He is a USCG rescue swimmer (they are doing a lot of in land rescues these days). I will title it "Batteries can fail"
Best,
------------------
Greg Davenport
http://www.ssurvival.com
Are You Ready For The Challenge?
Are You Ready To Learn The Art Of Wilderness Survival?
Silva lost the right to the name "Silva" in some markets (USA?), and they not long ago bought Brunton [partly] in order to sell their compasses under that name. So if it looks the same, it's reasonable to assume it's because it is. But perhaps made to be used in another part of the world.
And I agree with what Alan_B wrote. I didn't mean what I wrote to come across as anything else
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Urban Fredriksson
www.canit.se/%7Egriffon/
"Smooth and serrated blades cut in two entirely different fashions."
- The Teeth of the Tyrannosaurs, Scientific American, Sep 1999