I did a search on ETS and found most of the compass threads were somewhat older and possibly out of date. I recalled a recommendation for a Suunto MC-2 and when I searched for it on REI it is no longer available. Doing a google search I did find the compass, but at what seems to be an elevated price point now ($36 US being the lowest price point I saw, which I guess isn't too bad, up to over $80 US).

I looked through several of the threads on compasses (again mostly older threads) and found a recommendation for a Suunto MC-3. I searched and found a deal on one here .

So I was just wondering, is this still considered a good compass? Are there better options available now? DS and I need a good compass for our Scouting adventures and at that price point would make a great stocking stuffer for us. As always, thanks in advance for your help.

That one looks nice. I have a Brunton TruArc3 that works well for me, and is $8.49 on Amazon (no affiliation with either Brunton or Amazon).

Compass technology hasn't changed very much lately. if you look,you can probably find a perfectly fine compass used.

The one you reference will certainly work well; the declination offset feature is highly desirable. I like a compass with a mirror, like the MCB Mariner -useful as a signal mirror, shaving, removing thorns, etc.

A lot depends on just how you will use the instrument. All of these will point N, unless abused and will get you home. They will last forever, as well. My MC-2D is at least twenty years old and still aligns dependably.

The Suunto MC-2 is available on Amazon.com for around $40
The Suunto MC-2G (with a global needle) is available on Amazon for around $55

These are excellent compasses even compared to the British Military issue Silva Compass 4 baseplate compass.

If I was to replace my Suunto MC-2 is will be with a Suuto MC-2G.

http://www.amazon.co.uk/Suunto-SS0042520...ds=Suunto+MC-2G

That's true, but unfortunately the quality of Suunto products has changed for the worse in the meantime. I bought an MC-2G many moons ago and it served me well for about a decade. I had to retire it a little while ago due to the capsule developing a huge bubble, making the compass generally useless at higher altitudes.

I was very much dismayed about the capsule leak, which happened for no good reason. When looking for a replacement compass I noticed that the newer line of Suunto products is built of inferior materials and with much less attention to detail. Instead of getting a new MC-2G I decided to buy an entirely different type of compass altogether and I haven't had any regrets about my decision since.

Anyway, the MC-2G is a superb design, possibly the most practical out there. Unfortunately, it's let down by the less than stellar build quality, which has gotten worse in recent years. The MC-2G is still a decent compass for the money, but I could not recommend it wholeheartedly any longer.

True, but that isn't really saying much. Most of the compasses marketed by Silva are now made abroad, the quality is even worse than Suunto. The Silva 4 is a good design by all means but cheaply made, which is probably what makes it attractive to the military in the first place.

Probably the best Silva compass at this point is the 54B model, incidentally also used by the military. It is pretty expensive for what you get though, and it's a prismatic rather than mirror compass.

Any older (pre-2000) compass made by Silva, Sunnto or Brunto is a much higher quality product than the current crop. Therefore, buying second-hand would make a lot of sense if you can find a quality compass in good condition.

Thanks for the recommendation chaos, looking into that one on amazon.

hikermor, I didn't really think compass technology had changed all that much (which would certainly explain the lack of newer threads for them) but as I noticed the Suunto MC-2 getting harder to find, and as others have mentioned the changes that can happen over a year or two in the build quality, I thought I might ask to see if there are any other options available. As far as the use goes, I anticipate whatever map and compass or orienteering exercises DS might encounter in his scouting adventures (I do know they will need a reliable compass, as well as their ranger beads, to take a pretty precise bearing and go a certain distance to find hidden treasure for a Scout vs Wild camp out they have coming up in January).

AFLM, I see the MC-2 recommended a LOT, thanks for the source

Tom, I am disappointed to learn that the quality of the Suunto has decreased.

I was wondering about the purpose of the mirror on a compass? Other than it's obvious utilitarian use what is the purpose? In my mind I'm seeing it maybe being used to make sure you maintain your compass bearing as you get a line of sight (I'm sorry I'm not well versed in compass speak, I hope I said all that correctly). I almost ALWAYS have a dedicated signal mirror that goes with me so I'm not that worried about the utilitarian and signal mirror usage. If it has other important usage related to the compass I'd be interested to know.

thanks again everyone

For me,the mirror and its sight aperture allows a more accurate sighting on a terrain feature, cutting down on parallax error and variations due to shakiness in a hand held instrument... I am totally with you on carrying a dedicated signal mirror. in fact, I think the signal mirror is more critcal than the compass on most excursions.

For the trivial increase in weight, one then has two signal mirrors. If you want to attract attention, two mirrors flashing away should be really, really effective. I have never heard of this actually happening in real life. Perhaps others have? Aside from that, the capsule containing the mirror folds over and protects the mechanism (and just looks cool, to boot).

Another less common, but highly effective use of the compass. The first birthday present I gave my wife was a high end Suunto sighting compass, engraved on the side with "To Susan with love." It worked, as we just celebrated our 25th.....

Ok, the mirror is primarily used as a sighting device. Here's a good, short instructional video by Silva that covers the basics of map and compass navigation:
https://www.youtube.com/watch?v=4O8DmkAC2wI

Note that different kinds of compasses exist on the market. In general, a simple, inexpensive baseplate compass is the easiest to use with a map and the best option for learning the basics IMHO. Honestly speaking that's what I would recommend as a first choice if you're not quite sure what the mirror is used for. Maybe a Suunto A10 or equivalent, no need for anything particularly extravagant.

Mirror, prismatic and lensatic compasses have additional features and sighting aids for extra precision. However, they tend to be less user friendly as far as the basic functions and require more skill and experience to make good use of all the advanced features.

Also, many high-end compasses tend to be designed with a specific task in mind. E.g. a top-of-the-line prismatic compass is great for surveying or directing artillery fire but much less practical for general land navigation than a $10 baseplate compass.

A quality mirror compass is a wonderful tool, but only if you know how to use it effectively. For most tasks and users it's basically overkill. I love mirror compasses and I'm also very fond of my Cammenga lensatic for serious land navigation, but it's a different cup of tea. A baseplate is much easier to use for a novice and the learning curve is not quite as steep.

If the need is for basic land navigation, how necessary is any compass? My take is that a compass is rarely necessary, absent foggy/cloudy conditions or navigating at sea.

The vast majority of my experience has been in the topographic feature bountiful western US. Here you orient yourself and/or the map by aligning the terrain features and proceed up or down the ridge or canyon, heading for the peak, pass, or valley. I have gone weeks without referencing the compass. If you are operating in flat, featureless terrain or thick forest, it may be a different story. At sea, a compass is frequently used, at least pre-GPS.

I don't think a compass is strictly necessary. Neither is a steel knife, signal mirror or a box of windproof matches. People did just fine without those modern amenities for many millenia... Apart from those unlucky ones that didn't. History is full of folks who met their sad demise because they weren't really equipped well enough to survive.

On a serious note, it is possible to get by most of the time without a map and compass. Terrain association, sun and stars, it's all good. That said, I would put a quality compass very high on my priority list when it comes to navigation in unknown, unfamiliar or generally difficult terrain.

Much of my hiking takes place in dense woodland where conspicuous landmarks are few and far between. I have a pretty good sense of direction and I don't get lost easily (knock on wood!)... But I'd be pretty embarassed to admit how many times checking my bearings with a compass saved me from taking a wrong turn, and possibly from a potential disaster on more than one occasion.

YMMV - but if you don't carry a compass out in the bush you'd better make sure to include a signal mirror in your kit indeed, you might be needing it more often than usual.

Perfect description of a situation where a good compass will prove its value. Not really so necessary in sunny Arizona with its mountainous terrain. Like anything else, the need for a compass, and either other item, depends upon the environment, circumstances, and objective.

I think it is important for all compass users to clearly understand alternatives to compass use - navigating by sun and stars, for example. Be aware of local magnetic variation, which can range from the screwdriver in your shirt pocket to the iron content of the rocks surrounding your location. For that matter, be aware of the limitations of whatever map you may be using (out of date? wrong scale? no topo?)

While I often go months without referring to my compass, it is always in my pack, if not in my pocket. Any decent compass is light, quite reliable, and incredibly useful when you need it - a bit like a FAK (or a knife, matches, or signal mirror) when you think about it......

In the north with low sun angle in winter and hilly conditions & any cloud/fog with out a Compass you are done!

The map & compass topic is one of my favorites :-D

My thoughts ...

I think the knowledge of how to use a paper map (as in a USGS topo), compass, and GPS is vital for anyone spending time in the field. This includes understanding map coordinates (Lat/Long & UTM), how to a coordinate on a map, how to read a coordinate from a map, how to enter a coordinate into a GPS, how to use a map to set a compass bearing, ...

Suunto: My Suunto M3 (without mirror) purchased maybe 5-8 years ago is very high quality (no bubbles in capsule, smooth bezel movement, design). Probably my preferred compass across LOTS of them. I can't speak to the current quality.

Navigation by landmarks: Hikermor brings up a VERY good topic that is not mentioned much in forum discussions. Out west navigation using a map can easily be done using visual landmarks. When in a canoe on the Boundary Waters (northern Minnesota/Canada) I genuinely struggles to see features on the horizon, though I've found some people are pretty good at it. In the midwest U.S. navigation by landmarks is really tough. Unless you can spot a identifiable (on the map) antenna or tower navigation has to be done using the map itself. When in completely featureless dense woods or big water the only way to navigate is to get compass bearings from a paper map (field bearing) or to use a GPS with a electronic compass that points the way. The hand compass will certainly be more accurate. If you don't know how to do this the only thing the compass does for you is help you walk in a straight line (to where??)

GPS: The lack of midwest U.S. navigation landmarks is what has lead me to really appreciate the GPS. They get knocked for being battery operated, and I have found myself with dead batteries and no replacements, but that only has happened one time (never again). GPSs make navigation super easy, especially if the GPS is pre-loaded with expected important waypoints. Still, it is critical that users know how to use it, how to convert a GPS coordinate to a place on the paper map, and how to find the coordinate for a place on the paper map.

Type of Compass: I much prefer a good plastic baseplate compass with adjustable declination. Those without a mirror are good for rough directions ("head that way"). Those with a mirror are a much more precise tool ("head toward that big tree on the right"). I've read arguments that both are actually good enough. Since I use a GPS too, I can't comment on the accuracy of non-mirror vs mirror compasses alone. In dense forests a mirror is of little use.

Silva: This has been mentioned before, but do keep in mind that Silva in the U.S. is a completely different company than the original Silva in Europe due to U.S. trademark issues. I'd trust the Europe Silva. Not so sure about the U.S. Silva (I don't buy them because I feel the U.S. company stole Silva's good name and reputation - just my view). Brunton used to sell the real Silva of Europe compasses, but I don't know if that is still true today.

Brunton: This is one of the few U.S. compass makers. An being that I live in the U.S. I tend to want them to be good and high quality. For a while they were merged with Silva of Europe and at that time their product quality suffered (even though the pure Silva products were still high quality). Now Brunton has split away again ... but I'm not sure if their quality has improved (I hope so). Their simple rounded low-cost baseplate compasses are my preferred pocketable compasses (I even bring them to places like Disney World to keep myself oriented - yeah, such a compass nerd).

Military Style Lensatic Compasses (Cammenga & lower cost versions). Lots of folks love these. I bought a Cammenga and really tried to like it. I like the idea the capsule simply can't bubble or run dry ... but without adjustable declination I just didn't care for it. I strongly recommend a good plastic baseplate compass over the lensatic compass (unless you've had enough lensatic training to make up your own mind).

A small, but often significant point about topo maps. Consider the age of the map. I worked in a park where the topos were published in 1943. They were among the first to use the then new technology of aerial photography. As a result, the topography, with only a few exceptions, is spot on, but the cultural features are often missing. I have often used two maps,typically a recreation map, which is up to date on roads and trails, and a topo map for the really fine topographic representation. There area also some topo that do not show trails at all accurately; ground truthing must have occurred in a friendly neighborhood bar...

I have topos from the 1950s in my daypack. Last month, rehiking a section of the AT--that was rerouted thirty years ago--another hiker warned me that I was going off-trail. "Oh no: this is where the trail went in the seventies" just kind of threw him off.
We crossed paths a couple of hours later. He wanted to know if I was able to "stay on the old trail"...

I agree the Suunto M3 is a decent compass. Though to be fair, it has the same limitations as all the modern plastic body compasses marketed by Silva, Brunton, Suunto or Kasper & Richter (another good brand, but for some reason not mentioned very often).

The problem with most liquid filled plastic compasses is that the capsule might break or leak. It's not really a matter of if, but when. Mechanical damage, low temperatures, changes in air pressure are all contributing factors. To be sure, a compass is a precision instrument and should be taken good care of in the field. But stuff happens and my experience suggests even a high end modern compass made by a brand as reputable as Suunto can fail very suddenly and for no good reason.

The main problem IMHO is that the compass capsule is typically made of a relatively hard and brittle plastic liable to microscopic cracks (or worse). Then a bubble will form, at first maybe just a small one but it could grow exponentially at higher altitudes, maybe so much as to interfere with the needle movement. Alas, the Suunto global needle is particularly sensitive to that problem, it just doesn't seem to work correctly without liquid.

K&R has a different solution. They make capsules from a flexible thermoplastic, which expands or contracts depending on the outside temperature and air pressure. It is a sound concept and has been working just fine so far in my experience.

The Cammenga lensatic is an entirely different breed. I like it for what it is, and it is a very useful and reliable tool. Truth be told, you can navigate with a lensatic compass and map just as easily as with a baseplate compass, all it takes is getting used to a slightly different technique. The lack of adjustable declination is a disadvantage, but then again, many if not most "serious" compasses made for professional use lack that feature. Again, it's a matter of technique. You can always navigate by magnetic north if you don't feel like doing a little extra math.

Those who find the above beyond their skill would do better to invest in a land navigation class first. I have met a surprising number of people who bought a compass without really knowing how to use one, which they would never admit obviously. Maybe it's an ego thing but frustrating no less.

We are dealing with mechanical gadgets, any of which can be broken or fail for a variety of reasons. What should occur is that the user will be well versed in the proper use of the compass and map, be aware of potential problems, checking and constantly verifying. Backup strategies and ploys are always useful.

How many ways are there to determine north if your compass is on the fritz? (and the hoary "moss grows on the n side of trees" doesn't count)

For me, I can think of a few:

• Backup compass
• Technology
• Observe sunrise and determine where North is from where East is
• Observe stars and find Polaris
• Observe known landmarks
• Shadow stick method
• Analog watch method, if someone with me is wearing one

Yes, there is that. Anything made by man can fail. However, liquid-filled compasses tend to be particularly fragile in my experience. The Cammenga lensatic is a much more robust design on the other hand. A definite plus in my book.

Back in the early 20th century most quality compasses were dry - no liquid, hence no stabilized floating needle, which is a minus at a first glance. On the up side though, I've tinkered with WWI-era military compasses that were still every bit as accurate as the day they left the factory. Despite all the evidence of hard use - some of those toys had been clearly carried on the battlefield and had more nicks and dings than I could count. Compare that to my pampered top-of-the-line Suunto that gave up the ghost after less than a decade of very casual, low stress service.

For some time I did a lot of hiking with an old Soviet army wrist compass. (http://www.thesovietrussia.com/genuine-soviet-military-russian-compass-handheld-wrist-new-surplus) Chunky, primitive and really weird looking, but short of running it over with a truck it could take just about any punishment in the field. So my point is, take away the liquid-filled capsule and it's going to eliminate the Nr.1 problem by far with most modern day compasses.

As far as a low tech alternative to a compass... I think we know the answer to that already. Sun, moon, stars, terrain association - if available/applicable in the first place. A big IF indeed. YMMV but in my opinion there really is no alternative to a good compass other than another compass, GPS or some equivalent modern navigation aid.

with all the talk on how fragile some compasses are wouldn't it be prudent to find a way to protect it? At least while it's not in regular use. I must admit I've had concerns about my own compass, it's a cheapie clear base plate map compass and rides in a nylon compass pouch clipped to my pack. I'm wondering if it wouldn't be a good idea to see about finding a slim case (like the type for cell phones) it will fit in to help protect it.

This fragile compass talk puzzles me - my Suunto is more than twenty years old and still looks and works just fine. No bubbles at all. I generally stow it in an interior pocket in my pack next to the map when not in active use. When I am using the map and compass, it is tucked inside a shirt pocket and secured from loss by a neck lanyard. It does have a protective cover which houses the mirror - that may help its longevity. I also have a deck mounted kayak compass which is more than fifteen years old. It is doing just fine, although it hasn't been used quite as intensively in the last few years.

It would be truly bad news if compass quality has actually declined. When you really need to use a compass you more or less have to trust it completely.

I think SOME compass models have a well-tracked history of bubbles. I have two of Brunton's high-end "eclipse-style" mirrored compasses and have had bubbles in both ... and the manufacturer replaced them both for free.

Then again, I have something like eight Brunton base style compasses (used to teach map & compass skills), they are now about 10 years old, have been used a lot by young Boy Scouts, and NONE of them have bubbles.

I KNOW that liquid-filled compasses can withstand time and abuse. My base Silva Polaris compass purchased in 1970 - my first compass - has been used so much that its surface is almost translucent with scratches ... and yet it is fully functional and still has no bubbles.

I think there's a prevailing theme there. It seems that back in the day most compass manufacturers took quality control more seriously. Their products cost more relatively speaking but were made to higher standards.

To second Ken's experience, I have had my eye on a pretty old Silva, possibly from the late 70's, in near perfect condition (apart from the cosmetic nicks and scratches). Understandably enough, its owner would not part with it under any circumstances. Also, I have an Eastern European military issue liquid-filled compass in my collection, made ca. 1980 and with a lot of mileage. The capsule is still perfectly free of bubbles or defects.

Compare that to the current market offerings. Despite its excellent design, my ca. 2006 vintage MC-2G Suunto had some flaws even before the fatal capsule leak. The bezel developed slight play from use, nothing catastrophic but enough to affect the accuracy of readings up to maybe one degree. Not nice, or at least not what one would expect from a top-of-the line model made by a leading brand. I can attest from personal observation that the currently produced MC-2G is made to even lower standards.

I don't know, maybe I'm a little harsh on Suunto but I'm not the only person who's had serious issues with their products. A little while ago I came across this thread - clearly another unfortunate customer with a nice bubble in his almost new MC-2:
http://tasmania.bushwalk.com/forum/viewtopic.php?f=15&t=18780
Well, could be worse - the bubble in mine grows even bigger at some altitude. 4000' seems enough to do the trick already.

Just the other day I inspected the latest compasses at a local store (mostly Suunto, Recta and a few Silva models). Some of the less expensive (~$20) baseplate compasses - still in their original, unopened packaging - already had bubbles! The salesman retorted immediately that a bubble has no effect on the compass accuracy, therefore is not considered a manufacturing defect covered by warranty. Which is admittedly in line with Suunto's official warranty policy, so I suppose that's the end of that.

It's a shame really, but maybe now in the era of GPS the demand for quality compasses is decreasing so much that the manufacturers can get away with inferior products. Worse yet, a lot of people have started to treat compasses as disposable items. I know a local scout leader (and a great guy he is) who buys Silva and Suunto baseplate compasses by the dozen for his troop. Most compasses don't last longer than a few years due to "rough" handling and bubbles so they are replaced without much thought (not that it's a big investment in the first place). Curiously enough, a few of those inexpensive baseplate compasses soldier on for many years while the rest fall apart fairly quickly.

OK,here's a question - How MUCH does a bubble affect the accuracy of a compass and is there anything one can do in the field to reduce the inaccuracy? Deviations of one or two degrees are usually insignificant in most situations....

by my calculations, being off by just one degree, and traveling just one mile, you'll be off course by about 92 feet (roughly 8.7 feet off per every 500 feet traveled)

That would be true if the error is not random;even if that were the case one could rather easily observe the objective and arrive at the correct spot. Usually you are dealing with a swinging needle that goes on either side of the true azimuth. In practice, one does pretty well to be within two degrees.

As Hikermor mentioned. There is some deviation in a compass needle - especially when taking a bearing while on the move.

Unless someone is out in extreme weather such as fog or blinding snow where you cannot see your surroundings at all, there is no need to "dead stick" (our old school slang for needing a 100% accurate compass reading.) So being out 1-4 degrees over a mile with decent sight visibility of your surroundings is well within acceptable limits for 99% of hikers, hunters, boaters. And most times, you find the trail, road or boat dock you were navigating to.

IME a small bubble should not affect the accuracy at all. However, a bubble larger than 1/4" or so could already prevent the needle from swinging freely, introducing a completely random error that might be 5 or 180 degrees depending on how exactly you hold the compass and how the bubble moves inside the capsule.

A bubble this size is pretty bad. That compass needs to be repaired or replaced, either way it cannot be expected to give accurate, consistent bearings:
http://tasmania.bushwalk.com/forum/downl...4&mode=view

While a small bubble does not necessarily mean the end of a compass it's still a cause for concern. A small bubble is likely to grow bigger in cold temperatures and high altitudes.

Is it possible to repair a copass with this sort of defect in the field? I'm not sure. If there is really no other way you could poke a small hole and drain the liquid from the capsule. Unfortunately, that does not seem to work well in my admittedly limited experience.

Generally speaking, an accuracy of 2 degrees would be considered excellent, 3 degrees still acceptable from what I've been taught about land navigation. Keep in mind that even a compass in perfect working condition isn't really capable of perfect readings. IIRC, a top-notch prismatic compass has an ideal accuracy of +/- 0.5 degree. A good mirror or lensatic compass somewhere between 1 and 2 degrees. A baseplate 3 degrees or so.

This is the inherent accuracy of the compass and its sighting system (or lack thereof). It does NOT take into account user error or slight mechanical defects (loose bezel, slightly offset sighting mirror/sight line etc.).

At one point I had tried to remove a bubble by placing the compass near an incandescent light bulb for a while - to heat it up. I'd read somewhere online that worked. Well, it melted the capsule. Too close I guess.

I sent the melted mess to the manufacturer with the story telling them that if they chose to ignore me due to my own damage I'd understand it ... and they replaced it anyway. I'm thinking it must have been the first of the two mirrored Brunton Eclipse compasses.

By the way, feature-wise and for ease of use I really REALLY like the Brunton mirrored Eclipse compasses. It looks like they are called the "Brunton TRUARC 20" now. They added a global needle and it looks like they dumped the info cards. They says its improved now - I hope they fixed the bubble issue.

That compass has a smaller width mirror that lifts up which is not quite so good for signaling, but I would bring Doug's survival pak anyway so not a big deal for me. Still, you'd better check them for bubbles before heading out.

Put your compass in hot (not boiling) water will reduce or even remove air bubbles. Thats what I do occasionally.

Only temporarily. Expose the compass to low temperature and/or low air pressure (at high altitudes) again and the bubble will grow back IME.

Nevertheless, it is a quick fix for a little while at least. Also, that's why it's a good idea to carry a compass close to your body on winter treks and in the mountains - keep your compass warm and there's less chance of a bubble forming inside the capsule.

Checked out my compass this weekend, and my worst fears were realized. Apparently I either need a safer carry mode for my compass when not in use or a way to protect it in the pouch. When I checked it, at first I thought it was A-ok, no bubbles, then I noticed the needle was a bit wonky. Closer inspection revealed a cracked plastic casing that had allowed all the fluid to escape. Sad part is, I'm not sure how long it's been that way. I've recently picked up a new day pack that will hopefully give me the option to tuck a future compass safely inside the pack when it's not being used. I may also put it in some kind of hard plastic case or maybe an altoids tin for additional protection.

Its not really how old the Topo Map is, it how accurate it was when it was made and how much has changed in the area since. Accurate Map with very few changed = Good Useful Topo. Still given a choice I would take a Topo updated last year in comparison to one made 30 years ago.

Only 30 years? Working at Channel Islands National Park, I used topo maps that were produced in 1943. .The basic topography from that era is still in use today, more than 70 years later. Using them routinely from 1982, I found that the topography was usually spot on. Not so with cultural features, but that is why you carry a pen and pencil.

Interestingly, although the islands held still for their photos in 1943,the maps show nothing of the military camps and fortifications that existed at that time.

This situation is true for a lot of wild spots, at least in the western US.

The very best thing to have is good, sharp copies of aerial photographs. They typically are date stamped, and even for out of the way places like the Channel islands (US)there is now a plentiful selection.

The best map of the Channel Islands NP is National Gepgraphic's Trails Illustrated #252 - Channel Islands National Park. It is current on both topography and culture, but is still essentially the 1943 aerial photography. This is probably the case for many areas in this series.

You can never have too many maps/photos....

A bubble has almost no effect on the dampening quality of the rest of the liquid, nor on the compass' precision. In fact, it gives you an advantage at holding the compass naturally horizontally (working like a bubble level).

Also, I doubt that a hiking compass must be of a top quality overall as soon as it offers good enough rigidity of the casing and the needle axis is concentric with the dial. The rest is just your skills.

By the way, if the bubble is interfering with your aesthetics sense - use a round sticker in the middle of the top glass. If you don't see the bubble you are staying calm and your compass is leveled - exactly what you need to read the compass reliably.

I've got this http://www.ebay.com/itm/New-Professional...g-/281643293201 cheap model not so long ago and love it for map working, as it is much more precise and convenient to use than, lets say, a mirrored Brunton for $50. With that construction you are looking at the dial from the side through the integrated regulated dioptric loupe, not over a confusing and too close mirror, so you see the target, the readings, and the levelness quality simultaneously in focus. No more frustration trying to see something through the narrow slit in the mirror, the lid's window of this one is fully transparent. Also it has a photo tripod mount hole in the bottom, I'm sometimes using it on my hiking stick (which has a hidden photo head), when I want to make an exceptional azimuth fix. All metal casing, even though a bit clumsy finished.

Yes, I have used some very old ones as well. As long as you know the current declination for converting you magnetic azimuth to grid, and visa versa, then you are good to go. It gets really interesting when you are using some ancient mining maps produced in another language in a country where quality control does not exist. Makes for some interesting walks.

Sorry to burst anyone's bubble, but I have to disagree on pretty much all counts.

A large bubble can and will destroy the accuracy of a liquid-filled compass. The accuracy of a compass depends on the ability of a small magnetized needle to swing freely and point to magnetic north. The magnetic force that orients the compass needle is tiny, so it is important to ensure that the compass needle can turn without the slightest hindrance. That's why any decent compass will have a small jewel (usually sapphire) bearing to ensure a smooth needle movement.

A bubble inside a liquid-filled capsule essentially acts as an air pocket trapped against the housing. If large enough, it will block the movement of the compass needle and push it around forcibly as you move the compass and the bubble begins to shift back and forth. Once that happens the needle will no longer point north consistently. Instead, you will be getting totally random bearings with no way of knowing if any of them is actually right.

I don't speak about this from theory. I have seen it happen in real life and have done a fair bit of land navigation in my time, sometimes under pretty demanding conditions. YMMV but in my experience it is a scary proposition to be caught out in the wilderness with a compass you can't trust and no other effective navigation aid when you really need it.

There is absolutely no advantage to having a bubble in your compass. Other than highly specialized surveying compasses (usually prismatic type) that make use of a spirit bubble (attached separately to the compass housing) there is absolutely no point in adding that feature to a general purpose compass. Same for a photo tripod mount - what the heck is that all about? I see these features becoming more and more common on the cheap Chinese compasses sold lately. In reality, it's nothing more than a pathetic attempt to attract uninformed customers who'd be much better off getting a quality compass from a reputable manufacturer.

Actually, the eBay special on your link is a pretty obvious example of a low quality Chinese knockoff. As a matter of fact, I know that particular model well, it seems to be very common these days. I would not rely on that compass under any circumstances. The build quality is very low and the "advanced" features are a joke. I've had an opportunity to test three identical examples a couple of years ago. None of them would point north accurately, each was off by up to 10 degrees IIRC. Then again, not sure what more one could expect from a "New Professional Pocket Military Army Geology Compass for Outdoor Hiking Camping"?? Honestly, you would be much better off with any inexpensive baseplate compass made by a decent brand if money is a concern.

This probably is asking for something nonexistent, but are there any controlled studies demonstrating the accuracy/inaccuracy of bubbles in a compass? What would be critical would be the magnitude of introduced inaccuracy. For many purposes, a surprisingly amount of inaccuracy is quite tolerable.....

That's my point exactly. In fact, you can't expect a precision better than 10 degrees. Because anything you can get from a typical baseplate compass will have a comparable error introduced by its very design, dictating a certain overly inaccurate measurement technique. The cheap compass, I showed above, is having many of the issues of a typical ancient design resolved quite well. Yes, the parts are cheaply made, but they are doing what they supposed to do at improving the accuracy compared to any fancy plastic baseplate type. But I can easily agree that the 0 mark of its azimuth dial may be off by a bit. Though, I have checked mine for concentricity (mount it on a tripod in the open field, take a fix to one object, go around the compass and see what's exactly in the opposite direction (it has symmetrical sights), now rotate the compass on the tripod to point to that second object, and compare the new fix with the first one, must be 180 deg difference), it's ideal. And that's all what truly matters for a good compass mechanics. I don't mind correcting for the magnetic declination, so if I'll find that my dial is off for some degree, I will just use that delta along with the declination correction. Know your gear before you go anywhere.

Regarding the bubble, sure thing, if it's touching the sides already - the compass is defective and not usable, as the needle ends will be floating. I'm talking about rather small bubble, which is significantly smaller than the needle's length.

For the leveling - have you ever hiked in the steep hills with a compass? Especially liquid filled compasses may have problems there, as you have no natural sense of leveling it standing on a slope, and any equilibrium movements of the needle itself are effectively dampened. Leveling of any compass is very important if you are taking bearings to align with the map or directions list. A dedicated bubble level is nothing special and easiest to use leveling aid on the go.

Tripod mount for the compass is a godsend for triangulation, when you need to measure a distance, locate yourself precisely on the topo map between the benchmarks, or need to create such a map from scratch. Sure thing, for going out of the bush to a road a button compass on your watch band will do just fine.

A few posts earlier I wrote about the kind of accuracy that can be achieved in the field with various types of compasses. 2-3 degree accuracy is achievable with a mirror compass. Most of the time it isn't really necessary. Sometimes however, it is - and unless you have a working GPS at hand, a precision compass is the only tool that can help you out.

10-degree accuracy, which you've been referring to in your last post, would be a very poor performance by anyone's standard. Translated into mils, that's 178 mils or a deviation of 178 m at 1 km / 1.8 km at 10 km. More than enough to miss your mark completely in any kind of difficult terrain and/or low visibility.

For any kind of precise "triangulation" (I assume you actually mean resection) you'd need a highly accurate compass. Ideally a prismatic one, such as the British Army issue Francis Baker M73:
http://www.ravenlore.co.uk/html/prismatic_compass.html

These are very expensive toys, but note that they're not fitted with a spirit level or even a tripod mount. BTW, I've never had any issues using a compass on steep slopes. The magnetic needle itself is a good enough indicator if you're holding the compass level - if not, the needle won't swing freely anyway and it will be impossible to take a bearing.

As for a tripod mount, I can't see any utility in that unless you're a land surveyor using a professional surveying compass (the $5 eBay special isn't going to cut it). Keep in mind that pretty much any photo tripod out there uses a steel screw to secure the camera. Not exactly a good idea if you intend to mount a compass...

P.S.: If you want to check the accuracy of your compass I would recommend a better method instead. Go some place with a clear field of view to easily identifiable landmarks (such as mountain tops) as distant as possible. Take bearings to each individual landmark. Now take a good map (Google Earth works, too!), identify your location and measure the angles to each landmark in question. They should correspond more or less exactly with the bearings taken with your compass, correcting for the magnetic declination obviously.

Sorry, I am really late to this thread.

I appreciate TomL's comments on the issues surrounding a bubble's impact on acompass.

For my use a mirrored compass is the only way to go.

Blake

www.outdoorquest.blogspot.com

All of this is why I was always taught NEVER(when posible) to navagate directly to where you want to go, but to one side of a wide landmark(like a road). That way, when you reach the landmark you are SURE which way to go to reach your destination.

It is called deliberate offset. It works best when you have a linear terrain feature (or manmade feature) so that when you encounter this feature, you know which direction you need to go to hit your objective.

The only other MAJOR problem with an old Topo map is that the magnetic variation changes over time... Sometimes dramaticly!

The magnetic poles move around quite a bit...

Here is a very good link showing some rather EXTREME changes...

Magnetic Declination
http://www.compassdude.com/compass-declination.php

At least for most of the western US, changes in declination are fairly minor and predictable. What we haven't discusses is variation, the change in the compass needle orientation brought on by local magnetic bodies - everything from your neck knife or eye glasses to ore deposits. I have experienced variation of 35 degrees, which I am sure we will all agree, is just a tad too much...

I saw a variation of up to 90deg in the UP of Michigan because of old iron ore mines.

Don't tell me a little thing like being 90deg off is going to get you lost...

It certainly didn't help me find myself until I reasoned out the amount of error.

Another good source for declination info of an area is http://www.ngdc.noaa.gov/geomag-web/

I normally check the correct values before going into the field.

Blake

www.outdoorquest.blogspot.com

The problem with large variation numbers is that they aren't consistent, very local and then it's back to normal but you don't know it's back to normal and you're still trying to figure out how far off the compass is from where it should be.

A bit of celestial knowledge can be a god-send.

Yes indeed! In the case I mentioned, we had started before dawn on an ascent of Orizaba, the tallest of the Mexican volcanoes. My companion was navigating with his compass. It was a beautiful night and I had Polaris in sight,so we got straight quickly. The considerable variation was probbly due to iron in the surrounding lava flows.

Give me a starry night any day....

I've been following this thread with some interest. Here are some thoughts:

Need for a compass: Like hikermor and others, I find most of the time I don't really need a compass or GPS (although I always carry both). I spend most of my time in fairly rugged terrain, and just using my Mk I Eyeballs and associating terrain to map is all I need. However, as has been noted, in certain situations (relatively featureless terrain, poor visibility, etc) a compass is needed. I don't often need a compass, but when I need it, I need it bad!

Bubbles: Annoying, but unless they get rather large they aren't a big deal. It is usually fairly obvious when a bubble is big enough to interfere with the needle.

Compass in cold weather: Awhile back some of us were doing a navigation exercise in chilly weather. It was about +3 deg F (-16 C). Several people's compasses (all Suunto's as I recall) more or less stopped working! What seemed to be the cause is that the oil filling was getting so viscous that the needle could no longer move freely. My Brunton (Type 15) developed a bubble, but kept working. When they warmed back up the Suunto's started working again, and the bubble completely disappeared from my Brunton. Since in Alaska it does get cold now and then, a bubble is annoying, but a needle that doesn't move at all is unacceptable!

Awhile back I heard about the German made K&R compasses, which I believe someone else mentioned up thread. They might be the ticket for cold weather use. I recently ordered a K&R Alpin Sighting Compass. When I get it and get a chance to use it, I will post a report.

Accuracy with a handheld compass: Using a decent mirror sighting compass, you should be able to get withing 2 deg, plus or minus, if you are careful. This is adequate for most uses. I don't much care for lensatic compasses (though I confess I haven't a lot of experience with them). If you need better than 2 deg, I would go with a Brunton Pocket Transit. I've used them doing geologic fieldwork and they are an awesome instrument, but they are big, heavy, clunky, and cost $400-$600.

Declination and old maps: I would never rely on the declination posted on a map margin unless it was a really newly published map. Here around Anchorage Alaska, declination changes by about .34 deg/year. That means that the declination listed on a map published only 10 years ago would be off by 3 degrees or more. I always go to http://www.ngdc.noaa.gov/geomag-web/ to check current declination for an area.

Useful methods: I haven't found resection (or "triangulation") to be that useful for land navigation, though it is useful when boating. If I have several clearly identifiable landmarks around, I can usually figure out pretty closely where I am. However, I have sometimes found a variation on this method useful. If one is on a linear feature such as a ridge line, and has a single well identified landmark in view, one can plot an azimuth from the landmark to the linear feature and get a good fix. Deliberate offset (aka "angle off" or "aiming off") is also handy. The requirement here is that the objective be located along an easily identifiable linear feature.

Best type compass: For me, I find a good mirror sighting compass, with adjustable declination and a clinometer is the most useful. For getting a general direction I can use it like a baseplate compass. For more precise work I can use the sighting mirror. The clinometer is essential for getting accurate slope angles when traveling in avalanche terrain (those who don't go into avalanche country probably don't need it).

When I've needed a compass the Suunto MC-2G was more than adequate.


Lately all I use is a Suunto wrist compass which is lightweight and very convenient. I have a GPS (or two) just in case, but they're usually turned off.

"Just in case" is why we practice navigation with all the tools at our disposal rather than just using GPS all the time. Map & compass, map without compass -- GPS should be a training back-up, not a primary navigation tool. What's the fun in knowing where you are within a couple feet without doing anything but turning on an electronic device; try doing your navigation without the "tech".

Re the Pocket Transit... Maybe Orienteering with a compass that was a bit more accurate such as the Brunton Pocket Transit could be compelling. Does anyone geo-cache without a GPS?

Yep, the Suunto MC-2G is my current 1st choice as well. It has an "international needle" just in case I ever make it to Patagonia. I also sometimes use the Suunto M9 wrist compass, so I guess great minds think alike!

I've never even heard of the fluid inside a compass thickening or freezing, but I tend to avoid such super-cold conditions. I'd think keeping it close to the body and warm, like on a neck lanyard, should prevent that.

Having dealt with compass bubbles before, I've wondered why capsules are sealed instead of having maybe a thick, flexible and removable plug to deal with that.

I also have a tiny little brass compass as part of my EDC.

I once ordered a K&R compass years ago, but was unimpressed with it.

The Magnetic North Pole does move around, but I suspect it has a much larger impact in Alaska and Canada than in the lower 48. NOAA offers a website that provides current magnetic declination for any location, if you want to update old maps. [edit: as ASKAR already pointed out]
http://www.ngdc.noaa.gov/geomag-web/#declination

Army issue gear does not imply it's free of flaws. Take any prismatic disk based liquid filled compass and try tilting it a little in various direction, while looking through the eyepiece. You'll see what I mean. Also observe the speed your disk/needle goes back horizontally. It is slow enough to be a bad bubble level substitute, especially if you are in a hurry to make a quick fix at your walking direction.


My hiking stick/monopod is aluminum alloy, including the screw, and I see the utility in using it when necessary as I do have professional surveyor training and work experience (even though quite dated and with military roots; by the way, my military battlefield surveying tools were far less advanced compared to that $5 eBay compass, but still all of my rather small training targets were always hit from the second burst). Also, for those liking the mirror to measure azimuth of peaks and tall trees, what do you think will happen to your data, if your compass is not level when measuring at the top of the slit?


That's a bad method, as I can see at least 4 opportunities, where an error can be introduced (and not compensated by each other). Also "more or less exactly" is not an acceptable criteria for compass calibration either

So, I'm still not convinced that I must have a brand named $100 ancient mechanics plastic compass with the view obscuring mirror, instead of the $5 "prismatic", where the unreliable expensive prism on a hinge is replaced with the retracting direct view eyepiece (which is a huge improvement of the measurement technology having direct impact on reliability and precision).

Get a free planetarium app for your smartphone. Given it has a recent GPS fix (or you can tell and input your location coordinates within a 100 miles error spot) you can figure the magnetic declination measuring the azimuth of any visible celestial body with your compass (e.g. Sun, Moon, any bright star poking through the clouds). All of them are capable of showing the true azimuth of any celestial body in real time, just subtract the two.

Hmmm, the accuracy of those Planetarium apps is dependent on knowing where you are to synthesize the night sky. Further, the same cellphone that has the app also has a fairly accurate electronic compass. What's is our objective?

I'm Android developer having the best on the planet handheld Star Chart app in my portfolio (DSO Planner - it's not exactly the planetarium app, more like a professional tool, but still having similar capabilities). You can trust me on that:

1. The smart phone compass (and the inclinometer as well) is just slightly more precise compared to a primitive button compass. Moreover, its data is unstable (put it on the table note the azimuth and orientation, grab it, put back into the exact same orientation - most likely you will see a different azimuth value). Any real compass would work much better (and not consume the battery).

2. If you have a knowledge of your location with even a 100 miles error, your planetarium software will have an error in objects positions of just 1-2 degrees max (the Moon may have an additional 1 deg. error in a worst case due to the parallax effect), which is comparable or below the accuracy of your ordinary compass measurements. Besides, you have a topo map at hands to orient, right? (they usually have the coordinates grid or center's coordinates imprinted)

Even though you have a GPS on your phone, it wouldn't tell you the direction, unless you are moving fast enough or/and record and periodically monitor your trail path on the digital map. Don't be fooled with the car navigation apps, they are approximating your position and direction using the map data (aligning the GPS data with the road lines exactly).

??? This is way too complex! Polaris, the North Star is no more than one degree from true north. Find Polaris and you are looking north. End of problem. This has been common knowledge before smart phones, much less the apps you could load on them... Other stars are fixed in place, and with a reasonable amount of observation, serve equally well.

C'mon, that's just subtracting two numbers I'd like to see you finding Polaris at noon (if you are not at the North Pole in winter). Or when you are in the South America...

At noon, I would be using the big fusion reactor in the sky, which I would have been observing carefully since dawn. If I am ever south of the equator, it will be back to the drawing board. I understand there is something known as the Southern Cross....(but it only point south???) Better I should stay up north.....

There are plenty of ordinary situations when you cannot rely on just a single star, thus a compass was invented. The Southern Cross is more like a Southern Big Dipper. Just easy to identify (even though I had a trouble doing that at the first time long ago, as somehow expected a star in its center ), but it is quite far from the true South point for any compass calibration. My point is that a planetarium app on the phone can help you with any celestial navigation tasks from just objects identification to a serious sextant work.

I would think a compass was invented and developed for the proverbial dark and stormy night, especially when at sea. When i have been at the helm at night, I have used both stars and compass - pick a star that is on your bearing, and then steer by that. Just recalibrate every now and then.

I know that trick from my father, we sailed the Japan see a lot that way, really rural west shores, ancient motor boat. Wrist compass, no GPS, no radar, nothing. Just amazing starry sky above and the same stars below (glowing plankton). That's probably exactly what has triggered my deep interest to the astronomy.

Alex, maybe it's a matter of semantics to some degree, or a different approach to working with a map and compass in general but I'm not really sure I understand some of the points you've made in your recent posts.



I brought up the M73 Francis Barker because it's a darn good prismatic compass, and quite typical for its class. It's a mil-spec design but that is totally beyond the point. This is the kind of compass used for precision work in the field, with an excellent track record. Compasses of virtually identical construction have been used by soldiers, explorers and adventurers from Livingston to T.E. Lawrence, so I guess it says something about the longevity of the design.

Not sure where you got that "unreliable expensive prism on a hinge" - the M73 (and pretty much all comparable products) is built like a good old Swiss watch, plus it's plenty sturdy enough for serious field use. Those $5 eBay wonder compasses are not, IME.

The M73 - or any other similar prismatic compass - is capable of very precise measurements as long as the user is vaguely competent in its use. Among other things, this involves holding the compass in a reasonably stable and level position, which I suppose is straight-forward and self-explanatory enough.

I'm not exactly sure what you mean by your previous training or "battlefield surveying tools", but a precision compass is about the most basic tool used for field surveying, and also quite popular in some branches of the armed forces. The Brunton Pocket Transit, the US M2 artillery compass and the British M73 are good examples of their type.

I'd think that anyone trained in land surveying methods of any kind would be well familiar with that sort of equipment and the accuracy it can achieve. BTW, I have never, ever seen any professional mount a compass on a monopod (or a walking stick for that matter). The idea is beyond me, and I can't fathom what one could gain that way. A tripod-mounted surveying compass is a different matter - but now we're getting into a whole new ball game, which really has nothing to do with general land navigation.

Either way, any decent prismatic, lensatic, mirror... even baseplate compass can achieve an accuracy far better than what you stated...



In skilled hands, a modern baseplate compass can get within +/- 3 degrees (limited generally by the lack of sighting aids rather than any other inherent weakness).

The eBay compass that you seem to hold in high regard falls into a different category, however. If it works well enough to suit your needs, that is fine. But being familiar with that particular product, I would not recommend it to anyone.

I'm not saying everyone needs a "$100 ancient mechanics plastic compass" (??) with the "view obscuring" (uh-oh???) mirror.

I do believe however that anyone serious about outdoor pursuits of any kind should learn at least the basics of map & compass use. Once you master those fundamental skills picking a good compass - one suitable for your specific needs - will be an easy job. Either way, my suggestion would be to look for a quality compass you can rely on instead of wasting your money on inferior no-name products. Land navigation is a pretty serious skill, so there's really no place for worthless gizmos and inferior no-name products.

As always, YMMV

Tom, would that help if I'll explain that I've been serving in the Soviet army? Where most of the problems are resolved with a sledge hammer or with just a strong taboo word magic...

Let me explain the obvious to me "prismatic" M73 compass (P) flaws vs (N) $5 noname compass advantages as well:

1. P uses a prism on a hinge, N does not have any prism nor a hinge there (so the N is mechanically more reliable and less expensive to manufacture).

2. P's prism obscures the dial when engaged, N's dial is always open.

3. P has a fixed lens after the prism, N has an adjustable lens (great if your vision is not 20/20)

4. P has an eye sight slit on the prism's body. If you bend or damage the hinge you will have a wrong sighting if any at all if it lost (the prism's internal hairline will be shifted as well). N has that sight fixed on the monolithic compass body.

5. The P's prism mechanism has no hard stop in the engaged position (over the dial's glass), it is possible to have it engaged only half (or even if 7/8) way and have the measurements done without even noticing that. But in case of just slight misalignment of the hinge you will have a systematic error introduced. Yes, they are tested at the factory, but only in the 100% engaged position.

6. The dial of the P has their most precise ring numbers mirrored (prism is mirroring that image back to normal) - that makes it less readable for a direct view (asking for silly human error). N has totally normal numbers.

7. When you disengage the prism on P it's protruding far from the body making it vulnerable to various forces. N lens is screwing almost flat into the body.

8. P eyepiece lens is mounted almost on the surface (maybe 2mm deep maximum, and beveled out, why?), N lens is deep (about 5 mm) in the holding black tube (what makes it almost entirely glare free and protected from any abrasion chance).

9. P dial's degrees lines are obviously radial, N's are much closer to parallel being on the vertical slope (what makes it more reliable when taking measurements for fractions of a degree).

10. P's dial as visible from the eyepiece has no information about the levelness of the compass, N's side view reveals even slightest slope in any direction immediately.

11. When used in direct view mode, P has no bubble level and it is very hard to see if the disk is level or not from the top (easier with the needle - true). N has a dedicated bubble level on the top.

12. P and N have exactly the same front sight, which is a transparent window versus typical non- or semi-transparent mirror with a slit in non prismatic alpine compasses (that's the answer to your question about the mirror).

13. P has round body, N - square (what is better for map work?)

14. The tripod mount is great to have than not to have it at all. Perhaps, you could understand its utility better if you can imagine replacing the "tripod" word with the "sturdy and level table" words? Have you ever tried to map a terrain on piece of paper with an ordinary compass? I did, and I did the same with a theodolite on tripod as well.

15. There could be more.

Regarding the typical baseplate compass measurements precision. I meant the compound accuracy (mechanics, techniques, conditions). I said it is 10 degrees. You are insisting on +/- 3 degrees, but that's 6 degrees overall. Add dial/needle/sight view parallax errors, add lack of levelness, add impatience for needle setting - and you can round it up to 10 without a single doubt (I'm leaving magnetic anomalies and lack of mag.dec. precise knowledge outside of the scope). And that's exactly the ancient compass technology flaws, you have mentioned yourself, as the primary source of these errors.

Also I don't like the "skilled hands" notion. I understand the pun and paraphrase behind, but perhaps you don't? The skills here are is the deep knowledge of your tools and of the proper ways to overcome, amend, correct your data for any flaws they have and which might influence specific measurements. No mill.spec or the price guarantee you don't have any (see the list above). And I have stated at the very beginning that in the skilled hands all that matters in a classic compass is the concentricity of the dial with the needle pivot. The rest are just skills. However, the compass I've presented above is the improvement over the classic (ancient) model (the M73 is too, but the N is way better, because it's not struggling to be a Swiss Watch, but rather a very well thought out pocket compass). You can find the exact same scheme and features, which you can get for $5, in multiple models of $800 survey compasses. But there is no a single reason you have to pay 160 fold more to have all of that tech advancements, eliminating or minimizing many classic model flaws, for an ordinary field navigation.

The longevity of the design? Millions of happy users? The digging stick is much more reputable than a shovel then.

Alex, I'm afraid I have to politely disagree with you. It is entirely possible for a careful user to get within +/- 2 degrees using a mirror compass. This includes ALL of the compound errors. I have participated in compass training exercises which required walking a course and finding small, obscure targets. If you were more than 2 degrees off over a distance of 100 to 200 meters, you would walk on by and not find the correct target.

This kind of accuracy does require careful work, but it is doable.

I don't know what compass you were using, but maybe you simply had a too refined training setup? For example, the teacher could first measure the apparent Azimuth of the target from the start location with that exact compass and give you that number along with that very compass, even though the true azimuth of the target was off by 5 degrees, e.g. because of the compass dial excentricity. (by the way, the mirror already does not belong to the classic model we discussing, as it eliminates several obvious issues to some degree). Even a 0.1 deg. accuracy is achievable on a level table (with big enough dial), especially if you care to account for your particular compass pivot drag. But when you are on a trail and taking bearings every so often on the go, you will see my numbers or even worse ones. And the price of the compass wouldn't help to improve that if it is of a classic type with less than 2" needle. I believe that being conservative on your compass capabilities is better than rely on its ideal test conditions technical specs blindly.

Alex - dunno, I've played a fair bit with ex-Warsaw Pact compasses and on the whole, they tend to work about as well as comparable Western products. It's just that the overall package tends to be a little less refined and with fewer bells and whistles occasionally.

We could probably argue this back and forth, but I'll just add a few more points to consider.

1) The eBay special under discussion is basically a rip-off of the old German "Wilkie" compass (a similar, but not identical version is produced nowadays by K&R as Meridian Pro). The "Wilkie" was an excellent compass in its day, whereas the eBay version is made to far lower standards. BTW, the Meridian Pro has been "copied" as well by the same manufacturer, with equally unimpressive results:
http://www.ebay.com/itm/New-Professional...sid=p5731.m3795

2) Any type of compass can be damaged. Mirror, lensatic, prismatic, doesn't matter. What makes you think the eBay compass is less susceptible to damage than say, an M73?? A few examples of the same eBay model that I've tested myself have been very poorly made and on several I couldn't even open the cover properly because the hinge was bent so badly that it needed some manual "straightening" first.

BTW, I can't really imagine bending the prism hinge on an M73. I'm sure it could be done, but it would probably take a hammer and a lot more abuse than any compass could be expected to take.

3) What good does that spirit level do on a compass used for practical land navigation (as opposed to geology, surveying and such)? How do you focus on the compass needle AND the spirit level simultaneously? Myself, I find it a little easier to focus on the compass needle alone and at the same time it gives me a pretty solid indication if I'm holding my compass level.

4) As far as the M73, have you actually had an opportunity to use one in the field? I haven't been able to identify any real problems with its design or manufacturing quality and I certainly can't relate to your list of supposed construction "flaws". It's true that the M73 is not ideal for working with a map, I will give you that - but you still have the sighting line on the lid that gives you an accurate straight edge to work with.

BTW, the "Wilkie" ripoff does not exactly shine at map work either. A simple baseplate, or a mirror baseplate compass, would be more convenient for that purpose. A separate protractor would be even better.

Anyway, you have to ask yourself what you're actually trying to achieve with a compass. Basic land navigation? Orienteering? Drawing maps? Surveying? Horses for courses, each task calls for a specific type of equipment.

At the end of the day though, you get what you pay for. So...



Well, sadly - no, not in my experience at least. I haven't ever used a $800 compass, but I would always consider the good old M73 and the Brunton Pocket Transit (each about half that figure) a good investment if you're into that sort of thing.

For most people though, something from a $20 baseplate to a $50 mirror compass or the Cammenga lensatic would provide all the performance generally required in the field, in a reasonably reliable, easy-to-use package.

As for the $5 eBay wonders... Don't see them used much for any serious purpose, for a good reason I suppose.

And for all the stiff market competition these days and the Chinese churning out el cheapo compasses by the truckload... The good old Suunto, Silva, Brunton, Cammenga etc. are still in business. Maybe they're doing something right?

YMMV - over and out.

1+2. The Meridian Pro and the rest of your "copy sources" are using a prism. That's an obvious flaw in my opinion. Copies removed the prism and all of its mechanics completely. It does not matter that it looks bullet proof (it's definitely not, as it's not a solid piece of metal, but parts held with screws, actually). Surely nothing is unbreakable, only the time it will be able to withstand abuse matters. However if it's absent - it cannot break. I didn't find obvious "low standards" my $5 was built upon. Everything works smoothly, everything is aligned, good adequate materials used. If you've got a defective specimen - just return it and get a normal one. I'm looking at the "not impressive results" now - looks like a perfect copy to me, except that the prismatic engineering nonsense is effectively removed. What's wrong with that copy exactly what makes it less capable than the original?

3. I have explained that extensively already but again. Leveling. If the compass is not level, your measurements have an error. Are you agree with that? Yes. Have you ever tried to use a disk compass? Not just a classic needle one? They are different in handling. Looking from the top at the disk you cannot immediately say if it's perfectly level or not. 10 deg angle and you are off by 2 degrees (and that's if your disc has no significant buoyancy). There is no problem centering the bubble first and then taking a quick bearing looking from the top. Compared to guessing if it's level or not. But that's a bad method with such an advanced compass - just look through the eyepiece and at your target, you will be able to do all that at once - target, level, measure. A dozen of tricky skills polished with years of use of classic or even mirror compass are not needed anymore.

4. I have used the prismatic compass of the same kind many years ago, it was larger, but the same principle. So the images you provided tell me enough to judge. Construction flaws have nothing to do with the manufacturing quality. They are the drawbacks of that particular engineering design. The ideal engineering design is when you obtain a feature without adding a separate feature. Simple examples of the ideal design: a half serrated knife; a firesteel with a lanyard hole instead of a handle.


So, I must carry 5 different compasses @20-50 each, and a theodolite with a tripod on a trail? Merchandisers will love you! Sure thing, I'll take an universal device capable of many functions from a single package instead, adding only a bulk of knowledge how to use it for any of these tasks and limitations to expect (plus my Smart Phone, to keep that knowledge sharp at hand).

Chinese nonames are getting better with every day to come. That's actually should be obvious if you just think about the long term life cycle of the outsourced US (and the world's) manufacturing. When the Automatic Assembly Line (AAL) installed, lets say, in China is at the end of its life span, Mass production brands would just invest some small amount of their multi-billion revenue to order a new AAL (the other option - they can replace failing AAL's stages to a new ones), often switching to a new version of the product as well (e.g. a drastic change to a mould shape or a press form configuration could be cheaper if done from scratch along with the new process stage integration instead of modifying the old stage). But what then happen to the old AAL or/and its semi-functioning components? Right, they became an asset off some noname but very smart and highly entrepreneurial China businessmen. They buy them cheap, fix, modify, reassemble in their own AAL (nobody else but USA, EU, and Japan manufacture and service true AALs and components to them). So, basically there is very often no much difference in the mass produced copies of brand products other than a higher percentage of defective items passing the QC/QA (ask for a replacement), but as a compensation you can see some truly genius improvements to the old brand products sometimes and obviously an extremely competitive price (again, we are talking about simple produce such as a compass, which is nothing more than a magnetized piece of metal on a post in a box, stay away from Chinese iPhones ).

Wow! Lots of minutiae in compass types and variations, but it looks like all, or most, at any rate will steer you to your objective and back again, if used in anything like a proper manner.

There is another major variety we have not mentioned yet, the Suunto B-14/20 (the difference being either a plastic or aluminum housing). This instrument contains a rotating compass card and a viewing window. Observing and the compass card with both eyes open, the images are superimposed and a very accurate bearing is obtained - easily within 1/2 degree. I have worked with these primarily in cave surveying, along with a clinometer working on the same principle, and have seen surprisingly accurate results achieved.

Back when I was courting Mrs. Hikermor, I bought the aluminum version and had "To Susan with Love" engraved on the side. I am sure that compass is the reason our marriage has remained on course for a quarter century....Just another use for a good instrument.

This is a much higher class and already not just a compass but an optical device. Its major advantage is the precisely aligned collimating eyepiece. It's principle is similar to the red dot gun sight. Regardless of your head position if you see the marker it will be collinear with the compass major axis. What's very effectively removing another source of human error (alligning the front and back sights). Ideal for precise target sighting. Definitely a nice thing. I had experience with the similar type Sight Master (iirc), works great but extremely sensitive, a tripod mount would be a great addition. However, they are obviously having a limited use in the mountains, as you cannot extend a collimated sight far from the dial (optics limitation), nor tilt it far enough.

By the way, I love my scuba diving Suunto compass. As in a whatever awkward position you are - it will show you the horizon level and the azimuth (it has a weighted ball like dial). But surely it's way too enormous for a land use.

KB-14 looks like a decent compass.

Yes, the Suunto KB-14 is a very good compass if you're looking for maximum precision. To be fair, it has not really been designed as a general purpose hiking compass and tends to be impractical if working directly with a map.

For anyone interested in a direct comparison between various types of precision compasses I would recommend the following link:
http://www.itinorient-madrid.com/precision_compasses.php

I find the above comparison quite useful all in all. Obviously, some of the opinions regarding the handling qualities of a particular compass model are subjective, but the overall analysis is sound and the tables give a pretty good idea as to what kind of inherent accuracy may be expected from a given compass type.

Note BTW that the comparison includes the infamous "Wilkie" copy, which has been the subject of much debate earlier.

Also, I noticed there has been some confusion as to how the compass needle deviation is measured. The deviation error is usually expressed in +/- degrees, for instance, a compass may be said to have an accuracy of +/- 2 degrees.

However, that does NOT translate into a 4 degree error - it simply means that the maximum inherent deviation of the compass needle may be up to 2 degrees maximum from the mean (correct or spot on) reading.

Most precision compasses can achieve an inherent accuracy of well under +/- 1 degree under perfect conditions. The actual performance in the field is invariably going to be worse due to parallax, tilting and various other user errors. Still, like Aksar pointed out, a field accuracy of +/- 2 degrees is totally realistic with a good hand-held compass fitted with some sort of sighting aid.

A low-quality compass is a different story, especially if let down by poor damping and/or the absence of a good sapphire bearing that ensures smooth needle movement. This is really what separates quality compasses from inferior knock-offs - not the lack of extra features, but simply basic construction weaknesses.

Good reading, but... For the "Wilkie" copy, the guy simply didn't realize that the disk itself IS a leveling aid. Also the hairline need to be properly focused first to see the target and the readings simultaneously, that's different from KB-14 he's carrying. It looks like the same principle, but it is not, as you should not bring the eyepiece too close to the eye as required with KB-14, that will create several possibilities to introduce errors.

I'll definitely check the drag (caused by the friction) of mine, however the seller claims it indeed has the sapphire bearing. Also you should never assume it is 0 deg, no matter how "professional" your compass might claim to be, there is no such thing as "zero friction" in physics. You should always pay attention to the needle behavior. A 3 deg drag would be obvious to a naked eye, but I didn't notice anything that bad yet. Also he seem to assume it's 0 for all other compasses reviewed, except the 2 copies on the list (prejudice?).

His "parallax error" is exactly what's caused by the misaligned needle pivot and the dial. On mine it is tested 0. So he's either got a lemon or measured it wrong (e.g. the drag/friction effect could introduce that error being partially compensated by his measurements method). In fact, all you need to amend the drag, when you want the best accuracy, - bring a small ferrous thing to the compass from one side, remove, measure A1, bring it from the opposite side, remove, measure A2, then average the two A=(A1+A2)/2 - good to know trick if you stuck with a really bad compass (typical tech.for non liquid filled compasses of the past, as they were prone to rusting, but in most cases it was possible to disassemble them and polish the post's tip). By the way, a tripod mount will help here a lot again (also by the way: KB-14 has it ).

Oh, and I found the Sight Master, which I've been using, on the list, it's Silva SightMaster. It has a ruler on the side, aiding with the map work. It's strange that the KB-14 seem to have no such a simple to introduce feature (the guy's saying - it's not suitable for a map work). If not a ruler, just a parallel to the sighting line edge would suffice. Could be the specific way KB-14 is calibrated at the factory, though.

So, I would take these "tests" with a grain of salt, as his testing techniques, time of testing, and the subject compasses' history are unknown variables. Nice colorful diagrams are not a sufficient reason to take an action on this data

Got an unexpected package yesterday, looks like my sister sent DS's christmas gift so he could have it for this weekend's camp out. And guess what the gift is? Yes, a brand spanking new compass, a Suunto M3 (not sure which version I didn't look that closely at it but looks much more robust than what we've been using).

Looks like DS will have a very nice compass for the weekend and I'll get an upgrade too, from a busted compass that the fluid leaked out of to DS's old compass.

Congratulations Mark! I really like my M3.

I haven't been looking around for a while, but a while back my favorite how-to-use-a-compass site was this one:

http://www.compassdude.com/

With so few visual landmarks around here (in the midwest) the GPS and compass bearings are important.

well, DS got the Suunto M3, I just got his old crappy compass lol

our scouts got a bit of a lesson in taking precise compass readings this past weekend with our scout vs wild campout. The boys's scenario was they had boarded two planes, both then crashed, plane 1 was without injury, plane 2 had victims. Plane 2 had sent their location before crashing, so the groups in plane 1 had to first find their location on the map, then find the bearing to plane 2 crash site, and make their way there to "rescue" the victims.

While it all didn't quite go as planned (the boys were supposed to have time to return to base camp with their crash victims and then have time to find compass bearings to caches of food and other supplies before lunch, as it turned out it took them til about 2 oclock to get to their victims, perform first aid, and then mae it back to base camp) it was a fun weekend and provided the leaders the opportunity to see where the boys need to be guided for further training (namely map and compass and first aid lol). ALl in all a good experience for all of us.

Mark_F:

Scenario bases exercises are always fun and revealing. Good on you for providing your scouts this kind of learning opportunity!

Thanks aksar, we try. We all tossed some ideas around in the planning stages, but in the end it was the scoutmaster and an ASM who came up with that exact scenario.

Just a quick observation about compasses in the $20 range. . I had purchased several Suunto compasses back in the late 90's for use in geocaching. For at least the last 12 to 15 years they have been setting in gear bags in my closet.

Recently pulled them out and looked at them. . EVERY ONE had developed a significant bubble and for all intents and purposes was not real useful.

I realize you can't expect much, BUT I still have a Boy Scout compass that I purchased in 1965. It has NO bubble and is still usable.

Sad commentary!