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desdemona
01-21-2008, 15:47
I can see I need lots of work in the compass and map area.
I have a cheap compass (It has all sorts of other goodies like a very strong whistle and magnfier, so even if the compass is useless it is ok), and I was playing with it a bit yesterday. Not a terribly big deal since I was on a very well-maintained trail.


But I obviously dont' have much of a clue. Any really good books that have LOTS of illustrations. I am a very visual learner. I want a book with map stuff as well. (And GPS, though I don't intend to get one at this time).

Also help with getting a compass?? I want something with not too many bells and whistles. Just an inexpensive reliable model. Something I could get at REI say.

--des

Topcat
01-21-2008, 16:11
Go to the public library and ask for the orienteering merit badge book from the boy scouts. it is straight forward and easy.

Dances with Mice
01-21-2008, 16:24
Go here. (http://www.learn-orienteering.org/old/) It should answer most of your questions.

Bob S
01-21-2008, 16:28
I have a good book called “Finding Your Way In The Outdoors” by Robert L. Mooers I’ve had it for years. It’s pre-GPS (1972) but it has a lot of good info and some exercises you can do to become more comfortable with a compass. You don’t need an expensive compass to get by. A Wal-Mart $5.00 one will work fine. Better ones don’t point north any better then a $5.00 one. Just make sure it’s filled with liquid to dampen needle movement. Also anyplace that sells Boy Scout item will have a compass.

Nest
01-21-2008, 16:37
Yep, the Boy Scout book mentioned above will teach you all you need to know for what you want. As far as compasses, a good one can be bought for around $12-$15 at REI.
http://www.rei.com/product/408023
http://www.rei.com/product/727086
http://www.rei.com/product/738795

Any of these three will be all you need. For what you want a compass for, the fancier ones with all the attachments, aiming sights, and flip tops are just extra weight and money.

Now if you do want to get into more advanced map reading, this is the compass I have. It is one of the best ones I've ever used, and it's a lot cheaper than the higher end ones.
http://www.rei.com/product/737056

Looking at the first three I linked to, that's all you need to look for in a compass. A good flat base plate (the flat plastic piece on the bottom) is really nice. Make sure you can read the numbers. For example, the green one may be easier to read than the clear ones. Depends on your eyesight, but make sure you can read everything on the compass. One last thing is make sure the compass is liquid filled. I know some people may disagree, but I have always found that liquid filled compasses are more accurate. The are more stable, they don't sway as much, and the non-liquid filled ones can sometimes get hung up and give you a false reading.

The Old Fhart
01-21-2008, 16:44
An excellent book that is well written and easy to understand with plenty of pictures and examples is "Staying Found (http://books.google.com/books?id=U6KDPYrnNH8C&dq=staying+found+book&pg=PP1&ots=zt-0XsSbRD&sig=J9DyDYZ0lGYNMCfWFWTABVFmWWY&hl=en&prev=http://www.google.com/search?q=staying+found+book&sourceid=navclient-ff&ie=UTF-8&rlz=1B3GGGL_enUS208US209&sa=X&oi=print&ct=title&cad=one-book-with-thumbnail#PPA3,M1)" by June Fleming. Almost the entire book is on line at the link if you want to just read it but at $13 I'd go out and buy it.

Mags
01-21-2008, 16:55
Many local outdoor groups will also teach land nav 101 type courses for a very reasonable price. A book is fine, but sometimes hands on instruction (and practice!) is more valuable.


The New Mexico Mountain Club probably offers something: http://www.swcp.com/~nmmc/ (http://www.swcp.com/%7Enmmc/)

Also, you asked about a basic compass. The Suunto A-10 (http://www.rei.com/product/727086) or Silva 1-2-3 (http://www.campmor.com/webapp/wcs/stores/servlet/ProductDisplay?productId=13871&memberId=12500226)are good, solid and inexpensive compasses.

hammock engineer
01-21-2008, 17:44
Do a search online for your city and orienteering. A lot of places have courses set up to either teach you or a course you can follow. A good book is nice.

take-a-knee
01-21-2008, 18:22
One of four essays at Kifaru's site, be sure and look at the others:

http://www.kifaru.net/plot_blust.htm

Be an Expert with Map & Compass by Bjorn Kellstrum is a classic work on the subject.

Here is a link to Army Field Manual 21-26, a LOT of good info here. Study the first several chapters and be sure to peruse the chapter on terrain association, being able to understand and apply this concept is the key to "staying found" in the mountains

http://www.enlisted.info/field-manuals/fm-21-26-map-reading-and-land-navigation.shtml

Critterman
01-21-2008, 18:39
A great book is " Be expert with map and compass" by Bjorn Kjellstrom.

Rain Man
01-21-2008, 20:00
The Compass Store site might be helpful.

http://www.thecompassstore.com/

Rain:sunMan

.

Rain Man
01-21-2008, 20:13
A great book is " Be expert with map and compass" by Bjorn Kjellstrom.

You can get it for $1.99 on http://www.alibris.com

A great site for AT books, too!

Just FYI.

Rain:sunMan

.

rhjanes
01-21-2008, 20:14
Go to the public library and ask for the orienteering merit badge book from the boy scouts. it is straight forward and easy.

I orienteer with Ralph Cortney (He WROTE that book). In fact, we were up last weekend orienteering at his home BS camp.

Look up where you are for a local orienteering group. They teach map and compass work and are very helpful. You can guy a Orienteering compass at REI for about 13 bucks. You can then make a meet and test out your skills. A lot of orienteering clubs have events at city parks. Not quite as intimidating as going out to a 1000 acre BS camp!!!

rhjanes
01-21-2008, 20:20
Oh, and Orienteering, at the advanced level, is WAY more precise and complicated than hiking on blazed trails. Orienteering goes AWAY from any trails. We do stuff like "pick a route to go half a mile thru dense woods, locate your attacking point and then zero in on the man made object in the erosion gully". When you find it, the man-made-object is a broken down deer feeder, and you just shot thru half a mile of woods to locate it.

WalkingStick75
01-21-2008, 20:50
Great suggestions here. Once you get the basics go in your back yard and plot a simple square 90 degree turns, 10 paces or so. Sounds too basic but this is how I instruct PADI (scuba diving) students the basics before we go underwater. Expand on that by having a friend construct a simple course and see if you can repeat it.

Have fun

desdemona
01-22-2008, 00:00
Thanks for all the great suggestions!!

--des

ed bell
01-22-2008, 00:21
From a simple standpoint, I have found that once you can stare at a topo map and understand what it tells you, (i.e. the mountaintops, valleys, gaps become apparent) the compass, and learning how to use it falls into place. You don't have to be advanced in your skills to benefit. Study, study, study. I have stared at maps all my life and I love to walk trails after staring at the maps. Remember to understand scale and contour intervals. Some maps are laid out in a common fashion, and some are unlike others you typically see. Always check the legend. There have been lots of good links given here. It's a wonderful skill to have, and it might save your skin (or someone else's) one day.:sun

pure_mahem
01-22-2008, 08:01
Just so you know the usual difference between an expensive compass and a cheap one is how fast the needle will move to the north position. There are other things that will increase price incredibly such as tritium glow in the dark stuff and more detailed scales and declination adjust ability but a lot of the needed features can be found in the simple compass examples already given. FWIW the cheap walmart compass is just as good as any of the examples given. They use to sell a couple different Silva compasses but I haven't looked in a while so I'm not sure what they carry at the moment. I use a simple Brunton key chain compass and halve a backup on my 4 in 1 whistle that I use regularly. Yes I own a couple expensive ones but I don't use them much. For the most part I just carry it for a just in case. As suggested knowing how to read a topo map is agood skill to know and I can usually look at one and with knowing a couple of land marks be good to go. I use the Brunton to just maintain my direction if I'm headed somewhere when I can't see the landmark I'm headed for. Lot of good info posted in this link. I'm definately going to check out those army field manuals from that link.

NICKTHEGREEK
01-22-2008, 08:04
USGS Finding Your Way With Map and Compass.

http://erg.usgs.gov/isb/pubs/factsheets/fs03501.html

dloome
01-26-2008, 21:10
The best book I've found is Map and Compass Navigator published by Brunton. There are a LOT of different compasses out there. I would read a bit about backcountry navigation and the various compass types before purchasing one.

And while it's true that a Walmart compass points to North just like a Silva, this is only the most very basic function of a compass. Certain features like adjustable declination (and better materials and reliability) which add to the price are well worth it. There is absolutely NO WAY I would put any amount of trust in a cheap compass. A compass could very well save your butt some day- Don't try to save a few bucks here. Lots of good ones out there for under $50.

I always carry a Brunton Eclipse 8097 which I usually just use for map orientation. On winter or hikes where I know I'll be heading off trail, I swap it for a Silva Ranger CL which has a sighting mirror. While compass knowledge can be extremely valuable, don't forget to work on map reading skills as well.

Wilson
01-26-2008, 21:49
I made a living with a map and compass for 4 years, You don't need to be an expert or understand declination for a compass to be usefull. Just figure out the basics and use common sence.
Don't buy a cheap or expensive compass with an air bubble in it, it may be inaccurate.
Get a local map, take your compass and go for a little walk around the neighborhood. Pay attention to what the compass does as your walking in different directions...Its all very simple once you get the basic concept.

If you leave the trail, road, river, stream, ridge, whatever, just note which direction would take you back to some point of it. The more you use it, the better you will be at it.

take-a-knee
01-26-2008, 22:05
I made a living with a map and compass for 4 years, You don't need to be an expert or understand declination for a compass to be usefull. Just figure out the basics and use common sence.
Don't buy a cheap or expensive compass with an air bubble in it, it may be inaccurate.
Get a local map, take your compass and go for a little walk around the neighborhood. Pay attention to what the compass does as your walking in different directions...Its all very simple once you get the basic concept.

If you leave the trail, road, river, stream, ridge, whatever, just note which direction would take you back to some point of it. The more you use it, the better you will be at it.

Sorry, but understanding declination IS part of the basics of map reading, if you don't understand it, it will embarrass you at a minimum one day, or cause you some real misery. You don't have to be able to explain mercator projection to a class to navigate, but if you don't understand declination, you can't translate data from map to compass.

Pedaling Fool
01-26-2008, 22:16
Especially when using a compass in Maine.

woodsy
01-26-2008, 22:29
Sorry, but understanding declination IS part of the basics of map reading, if you don't understand it, it will embarrass you at a minimum one day, or cause you some real misery. You don't have to be able to explain mercator projection to a class to navigate, but if you don't understand declination, you can't translate data from map to compass.


Especially when using a compass in Maine.

Declination is an important aspect of navigation by map and compass, like both John and take-a-knee stated.
Declination here in Maine is about 18 degrees. Without adjusting for declination, you could find yourself some distance from where you expected to end up, depending on how far you traveled .

Wilson
01-26-2008, 22:35
Takeaknee, Your first part of your statement is "by the book" and correct.
Declination, if I recall correctly is the diff between magnetic north and true north. Some parts of the world it can be a big difference. Around here not that much.
Its been almost 20 years since I *had* to use declination. That was as an artillery spotter. For hiking and hunting I've never bothered or have it factor in at all. I just use the 8 basic directions, not trying to find a geocache.

Unless I was doing an orienteering course, how would not using declination embarass me?
Where'nt you stationed in Alaska? further north declination can be more severe I would think.

Wilson
01-26-2008, 22:38
Excuse me..just read the 2 post from maine 10-4....I take back what I said about declination, except for areas where it is zero or relatively small.

warraghiyagey
01-26-2008, 22:38
Declination is an important aspect of navigation by compass, like both John and take-a-knee stated.
Declination here in Maine is about 18 degrees. Without adjusting for declination, you could find yourself some distance from where you expected to end up, depending on how far you traveled .
What's a declinashin??
http://www.freesmileys.org/smileys/ad/hiding.gif

The Old Fhart
01-26-2008, 22:53
Woodsy-"Declination is an important aspect of navigation by compass, like both John and take-a-knee stated.
Declination here in Maine is about 18 degrees. Without adjusting for declination, you could find yourself some distance from where you expected to end up, depending on how far you traveled ."Absolutely correct. If you ever wondered how far off you'd be, I figured it out mathematically and if you made an error of 1.1 in your bearing and walked 1 mile, you'd be off 100 feet. If you didn't correct for declination and it was 18, in 1 mile you'd be off aproximately 1600 feet, or about 1/3 mile which I'd consider significant.

The only area where declination isn't important is along the 0 isogonic line, roughly Wisconsin through Florida.
3160 Isogonic lines -click to see full size

Montego
01-26-2008, 22:53
What's a declinashin??
http://www.freesmileys.org/smileys/ad/hiding.gif

Ah.....thinks it's some sort of paper a buncha people signed, giving us freedom, or something like that :D

Wilson
01-26-2008, 22:54
I've got a ton of trail and other maps here ...and except for my old military ones of Fort Bragg, none of them even list the declination difference.

Seems like there ought to be a lot of lost folks out there. Kidding.

warraghiyagey
01-26-2008, 22:58
Ah.....thinks it's some sort of paper a buncha people signed, giving us freedom, or something like that :D
OH!! Got it. http://www.freesmileys.org/smileys/ad/patriot.gif

Montego
01-26-2008, 23:04
OH!! Got it. http://www.freesmileys.org/smileys/ad/patriot.gif

Well heck Warrgey, I may be a OKIE, but that don't mean I don't know that the "Declinasian" of Indepenence is! http://www.freesmileys.org/smileys/char020.gif

Bob S
01-27-2008, 03:09
I never really worried about declination as most of my camping is almost due north or due south from me. And I’m only 2.5 degrees out (Toledo Oh.) of true north not enough to be worried about.

Now I use GPS and I have it set to true north, it automatically corrects for declination. I still have a compass & map with me, but GPS has taken the main stage for use.

Two Speed
01-27-2008, 08:06
desdemona, lots of good suggestions and material offered here so I won't try to add to it; there's plenty for you to look at.

The main thing is that by taking the time and effort to inform yourself you're doing the right thing.

Knowing how to use a map and compass is a basic skill that EVERY outdoorsman/woman should have. Being good at reading a map and working a compass will not come in a day; you will have to work at it. However, this is one of those things that pays off in spades. Once you learn to read a map you can find water more readily, find stealth campsites more to your liking, etc. All of those benefits are aside from the main bennie, which is greatly reducing the probability of being lost and confused one day.

Short version: what ever you do, get started.

Yeah, it'll be confusing from time to time, but once you get the hang of it you'll thank yourself for making the investment in building your skills.

10-K
01-27-2008, 08:30
I just learned about declination in detail this month in the Outdoor Survival course I'm taking. It is very, very important! For instance, in Maine with an 18 degree west declination if you did not adjust for it you'd be off almost 1/3 of a mile after walking only 1 mile!


Find *your* declination here: http://www.ngdc.noaa.gov/seg/geomag/jsp/struts/calcDeclination

The Old Fhart
01-27-2008, 09:30
TOF (POST #28)-"...I figured it out mathematically and if you made an error of 1.1 in your bearing and walked 1 mile, you'd be off 100 feet. If you didn't correct for declination and it was 18, in 1 mile you'd be off aproximately 1600 feet, or about 1/3 mile which I'd consider significant."

tbradnc (POST #35)-"For instance, in Maine with an 18 degree west declination if you did not adjust for it you'd be off almost 1/3 of a mile after walking only 1 mile!"Declination is very important as those two quotes show. Also understanding the difference between map/compass and GPS is important as well. A compass only indicates the direction of travel and if you don't know exactly where you are initally, you could be walking parallel to where you think you are. A modern mapping GPS will tell you where you are, generally within about 20 feet, and if you mark the point you have chosen as a destination, the GPS always points toward your destination, even if you have to go around obstacles like cliffs/lakes where you would have to calculate offsets if you were using a compass. The GPS also leaves a trail of electronic 'breadcrumbs' on the map on the screen so you can easily backtrack.

It seems that hunters, fishermen, snowmobilers, and ATVers are seeing the importance of GPS and accepting them faster than hikers. The State of New Hampshire just completed mapping and marking 1000 miles (7000 miles left to go) of snowmobile trails (http://www.wmur.com/news/15114165/detail.html) (click on link) with GPS and this has already been used to help snowmobilers in trouble. The GPS data for the A.T. on the ATC site was taken about 2001 and is quite out of date.

micromega
01-27-2008, 10:06
Just to be clear, since no one seems to have mentioned it, declination is only important when using map and compass together. There is a lot that can be done by compass alone without any need to understand or correct for declination.

It is also possible (though not advisable) to do rough navigation by map and compass while disregarding declination. It won't be precise and involves some risk, but in an emergency situation it can be done. That said, learning and understanding declination is simple and easy enough that its foolish not to.

russb
01-27-2008, 10:26
Declination on a map is more important than "true north" IMO. In fact I don't even look at true north on the map. Magnetic north is all that is necessary. If one solely uses magnetic north, then even knowing the declination (degrees) is unnecessary.

I understand the argument that other outdoors people are embracing GPS more readily than hikers. I think of it this way:

Some choose to use snowmobiles to reach a destination while I use snowshoes. Their method, which uses more advanced technology than mine, is much more efficient. However, their technological solution also has other limitations such as fuel requirements, breakdown possibilities, and environmental obstacles. Also for me it is not the destination but the journey. I hike the trails not just to get somewhere, but to enjoy myself. Yes I understand that snowmobilers (I do not mean to single them out, they serve just as an example) also enjoy their journey but it is in the same vein as HYOH. We all use technology to enjoy the outdoors, we all choose what technology (or do not choose to use that technology) to make our own time in the outdoors enjoyable for us. everyone's list of "acceptable technology" will be different. Another example is free-dried food. I like to cook, it is part of what makes my time in the outdoors enjoyable. Commercial freeze-dried food is a technology I choose not to use. In the end HYOK and navigate with whatever tools make it enjoyable for you, or ride the ATV if that suits you too. :)

take-a-knee
01-27-2008, 10:34
Just to be clear, since no one seems to have mentioned it, declination is only important when using map and compass together. There is a lot that can be done by compass alone without any need to understand or correct for declination.

It is also possible (though not advisable) to do rough navigation by map and compass while disregarding declination. It won't be precise and involves some risk, but in an emergency situation it can be done. That said, learning and understanding declination is simple and easy enough that its foolish not to.

I did mention it Micro (post #22). If you buy a compass like a Silva Ranger, it can be set for the declination for your area. You just have to remember to reset it when you travel to a different area.

micromega
01-27-2008, 11:17
Sorry, but understanding declination IS part of the basics of map reading, if you don't understand it, it will embarrass you at a minimum one day, or cause you some real misery. You don't have to be able to explain mercator projection to a class to navigate, but if you don't understand declination, you can't translate data from map to compass.

I'm sorry, Take-a-Knee, maybe I'm being obtuse, but I don't see how you're saying anything about declination being irrelevant when using compass alone?

Also, for my second point, I'm saying you can translate data from map to compass without compensating for declination as long as you accept that it will not be an accurate translation. By doing so, one would need to accept the risk that, as you so aptly put it, "it will embarrass you at a minimum one day, or cause you some real misery".

There is no excuse, really, not to understand and use declination adjustments, in most cases. But for someone new to the concept, I wouldn't want them to feel they cannot use compass until they wrap their brain around declination. If you have a map and compass, using them in a familiar setting like a local park will provide benefits whether you understand declination or not. Experimenting with and without declination in a familiar setting is also a great way to understand the concept.

Topcat
01-27-2008, 11:53
If not already on the map, I always mark magnetic north on it and use that line for all my shots and bearings. For me it is easier than doing the math in my head.

In this day of GPS, some people are losing this skill, but it is an important one, maybe not on the AT but check out some of the CDT journals and see how much time people spend trying to find where they are. Of course, your never really lost, just taking the scenic route.

russb
01-27-2008, 12:25
If not already on the map, I always mark magnetic north on it and use that line for all my shots and bearings. For me it is easier than doing the math in my head.


That is exactly what I do. I actually draw in parallel lines for magnetic N that are same width as my compass across the entire map to make it easier.

10-K
01-27-2008, 12:38
That is exactly what I do. I actually draw in parallel lines for magnetic N that are same width as my compass across the entire map to make it easier.

Either way will work. I use a baseplate compass and find it easier to orient my compass with the map rather than change the map to work with my compass. Same thing, less work.

Thanks
Thomas

mudhead
01-27-2008, 13:24
The only area where declination isn't important is along the 0 isogonic line, roughly Wisconsin through Florida.
3160 Isogonic lines -click to see full size
cool.

!


Find *your* declination here: http://www.ngdc.noaa.gov/seg/geomag/jsp/struts/calcDeclination

Thanks for that. I have been using 19 degrees since the sixties.
Time to get into the current century.

Bob S
01-27-2008, 14:30
GPS is no different then any other new technology; some people will never want to embrace it. They will say it’s foolish to rely on it; it will never replace the tried & true, what if the batteries go dead, what if you drop it, what if it gets wet, Bla, Bla, Bla.

I’m sure the first autos were looked at like this; people said they would never replace the horse. I’m sure they gave lots of reasons for the horse being better. But the auto did take over and is never going to have a horse come back and replace it except in a very select situation in the remote outback. Even then one could argue that an oil-driven vehicle of one kind or the other could do the job of the horse.

I was watching a story (on PBS) about how writers first thought the computer publishing programs were going to destroy their future. They were sure the typewriter was the best / only to write a story. They were afraid of the computer. And the story pointed out how now every writer loves the fact that the computer allows them to be much better story tellers then the typewriter ever could, like the GPS and compass comparison the computer & publishing program does things the typewriter never could. The computer has also allowed more people to become writers much easier then before. It’s the same way with GPS, it opens up the outdoors to more people then the compass did. And it does it better then a compass ever will be able to. It allows people to get out and get back safely.


I have had a GPS for 4-years, it has never failed to work for me, it does things (very helpful things) that a compass cannot do. And GPS will continue to get better and less expensive and become even more reliable. In time, as with the horse even those of us that love the compass and argue it is king will see the GPS as a better tool to take onto the trail. After all, how many people now live by the horse in their life and no autos? I know someone will post about a situation (someone they know of) that still uses horses only. But this is not a good argument as this horse person is on the fringe of humanity, not the mainstream.


I always have a map with me, because I like them. I always have a compass for the just in case moment if the GPS were ever to fail. But the compass almost always stays in the backpack. I think it’s important to learn and understand how to use a compass (I did this years ago in Boy Scouts) as it has made my understanding of GPS better. But it’s not the king of back country navigation it once was.


Criticize GPS all you want, but it like the computer publishing programs and the auto, is here to stay. This is not a bad thing.

PS everyone can afford GPS, E-Bay has used ones with lots of life in them for sale at very good prices. I bought my GPS at Office Max for only $119.00 4-years ago. Prices are dropping all the time.

russb
01-27-2008, 15:10
Either way will work. I use a baseplate compass and find it easier to orient my compass with the map rather than change the map to work with my compass. Same thing, less work.

Thanks
Thomas


I use a baseplate compass to, it find it easier to orient the compass on the map when I have the magentic north lines right on the map when I point the compass edge in my desired direction of travel. You are right though, it is a little more work, but for me, it saves time in the field. It is fascinating that we all use slightly different techniques, likely due to how we were taught (or figured out). I know I learned my technique from my father. In fact the compass I have was a gift from him when I turned 10 and proved I knew how to navigate with one. A Silva Huntsman, still have it and use it.

russb

10-K
01-27-2008, 17:16
I use a baseplate compass to, it find it easier to orient the compass on the map when I have the magentic north lines right on the map when I point the compass edge in my desired direction of travel. You are right though, it is a little more work, but for me, it saves time in the field. It is fascinating that we all use slightly different techniques, likely due to how we were taught (or figured out). I know I learned my technique from my father. In fact the compass I have was a gift from him when I turned 10 and proved I knew how to navigate with one. A Silva Huntsman, still have it and use it.

russb


I agree Russ, and didn't mean to come across like an expert navigator. I've learned 90% of what I know about using a map and compass together in the past 4 weeks.

If I'm going to be out and about in the woods I figure spending some time learning about navigation and first aid will be time well spent.

Thanks
Thomas

jzakhar
01-27-2008, 17:35
anyone know if it is possible to determine the magnetic declination of an area with a standard compass ?

The Old Fhart
01-27-2008, 17:53
Can't be done with just a compass. Post #44 gives 2 good ways to determine your local declination.

russb
01-27-2008, 18:01
anyone know if it is possible to determine the magnetic declination of an area with a standard compass ?

Yes, but one would have to know true north. Thus to accomplish this feat, I would wait until nightfall to establish true North via Polaris (the North Star) which is within 1-degree of true North. From this direction, I would calculate the difference between my compass reading of North (magnetic North). This difference is the declination.

As long as one has a method for determining true north, then it is possible to calculate the declination with a compass. There are many ways to determine true North. The stick-shadow method takes a long time, but maybe less than waiting for nightfall with a clear sky. ;)

russb
01-27-2008, 18:03
I agree Russ, and didn't mean to come across like an expert navigator. I've learned 90% of what I know about using a map and compass together in the past 4 weeks.


I am no expert either.


If I'm going to be out and about in the woods I figure spending some time learning about navigation and first aid will be time well spent.



Plus it is fun, IMO. :)

The Old Fhart
01-27-2008, 18:19
russb-"Yes, but one would have to know true north...."Ah, but the ways you go on to describe, although workable, depend on visibility/weather, and technically use more than just a compass. In order to calculate declination you have to have a reference which means you have to know true north, as you have said. Sextants, GPS, map and known landmarks, or just the declination arrow on the map legend will give it to you.

Just carrying a map for the area with the declination on it is the simplest way-use the K.I.S.S. principle.;)

russb
01-27-2008, 19:14
Ah, but the ways you go on to describe, although workable, depend on visibility/weather, and technically use more than just a compass. In order to calculate declination you have to have a reference which means you have to know true north, as you have said. Sextants, GPS, map and known landmarks, or just the declination arrow on the map legend will give it to you.

Just carrying a map for the area with the declination on it is the simplest way-use the K.I.S.S. principle.;)

Yes I suppose you are correct in a technical sense that one's knowledge and other natural phenomena extend beyond "just a compass". Somehow I thought the question had a more practical basis. Though One would never need to know the declination unless one had a map, which of course as you mention has the declination on it. Though a very old map would be off.

Love your name BTW.

10-K
01-27-2008, 19:41
Yes, but one would have to know true north. Thus to accomplish this feat, I would wait until nightfall to establish true North via Polaris (the North Star) which is within 1-degree of true North. From this direction, I would calculate the difference between my compass reading of North (magnetic North). This difference is the declination.

As long as one has a method for determining true north, then it is possible to calculate the declination with a compass. There are many ways to determine true North. The stick-shadow method takes a long time, but maybe less than waiting for nightfall with a clear sky. ;)

We learned how to find north with a digital watch too. ;-) It's actually very clever, I would have never thought of it.

Thanks
Thomas

russb
01-27-2008, 20:04
We learned how to find north with a digital watch too. ;-) It's actually very clever, I would have never thought of it.

Thanks
Thomas

Don't forget to factor in daylight savings time if applicable. ;)

Mags
01-28-2008, 11:57
GPS is no different then any other new technology; some people will never want to embrace it. They will say its foolish to rely on it; it will never replace the tried & true, what if the batteries go dead, what if you drop it, what if it gets wet, Bla, Bla, Bla.




It is a tool like anything else. Like any tool, it has its uses. It also has its limitations.

A map, compass and GPS all work wonderful together for different reasons. Sometime is it just quicker to pull out a map and take a quick bearing.
Other times getting your exact location in a featureless terrain (desert for example) is very nice with a GPS and plain hard with a map/compass.

And just like a car is useful at times..you better know how to find alternative methods if it breaks down. :) (Public transit, giving a friend a call, AAA, etc.).

Peaks
01-28-2008, 18:06
And while it's true that a Walmart compass points to North just like a Silva, this is only the most very basic function of a compass. Certain features like adjustable declination (and better materials and reliability) which add to the price are well worth it. There is absolutely NO WAY I would put any amount of trust in a cheap compass. A compass could very well save your butt some day- Don't try to save a few bucks here. Lots of good ones out there for under $50.

.

You should not need to pay more than $10 to $12 for a good basic compass.

rhjanes
01-28-2008, 18:20
That is exactly what I do. I actually draw in parallel lines for magnetic N that are same width as my compass across the entire map to make it easier.

Our Orienteering maps, even do that for us! Line up the base plate in the direction of travel.....rotate the lines to the NS line, proceed in the direction indicated, noting land features MATCHING your map.

Oh, and on declination, it DOES change. Plus, read the fine print on the maps! Most Orienteering maps, are considered "local" and they have it corrected on the map (put you declination adjustment on zero). But CHECK. Our local club is having a national orienteering meet (maybe even some internationals will attend, they have before). I know the organizers will be making lots of anouncements that the declination is factored in the maps, so set to zero.

woodstock64
12-11-2010, 23:00
Bob S. While I agree with you that GPS is a great technological advance, until battery technology becomes vastly improved, I will always choose to carry a compass on the trail. As to your ascertain that "Everyone can afford a GPS" in light of our current recession, I would say that pre-recession quote sounds awfully presumptuous now.

swjohnsey
12-11-2010, 23:14
anyone know if it is possible to determine the magnetic declination of an area with a standard compass ?

You can do it if you can find the North Star. North Star for practical purposes is true north. Grid north is close enough to true north not to make a difference. Compass needle points to magetic north. Difference in azimuth between North Star and Magnetic North is declination.

fiddlehead
12-12-2010, 07:52
I always thought that Mississippi river was about the 0 deg. line.
Now, i see that it is about 5 deg East and the 0 deg line is much further East.

I too need to look it up from time to time.
I agree that 99% of the time, my compass stays in the pack and the GPS is readily handy.
But it is good to know both.

You don't hear nearly as many naysayers anymore since they are in most cars and those who wouldn't go near them, are now forced to have them around and even people who never even owned a compass never get lost anymore.