Kjetil Kjernsmo's illustrated guide on

How to use a compass

Buying a Compass

I've been a bit hesistant to write this page, because I really didn't want to promote a special brand of compasses or anything. What kind of compass one should buy is a major concern of those who e-mail me, so I figured I would give some advices.

First, I want to emphasize that, while I have tried quite a few types of compasses, they haven't been made by many different manufacturers, and the list of compasses I present here will necessarily be reflecting the fact that I am in one of the Nordic countries, and I know the compasses manufactured around here the most. That doesn't necessarily mean compasses made in e.g. the US or Australia are any worse, I just don't know them.

Finally, my area are orienteering and compasses for hikers. I have very little experience with e.g. naval compasses (though I have tried it too).

What kind of compass you should choose will very much depend on your typical use. However, my general advice would be: Make it as simple as possible.

In competitive orienteering, a small revolution happened at the begining of this decade: Orienteering compasses became a lot more stable and fast over night, as it was discovered by a swedish orienteer that the home-made compasses of russian orienteers were extremely good. You cannot normally tell the difference between a normal compass, and these new compasses, unless you run or perform a simple experiment: Hold the compass flat in your hand, and let the compass needle stop. Now, turn your hand so that the needle is vertical, now you can turn yourself so that when you put the compass flat again, the needle is not pointing north. Observe how fast the needle gets back to pointing north. Actually, with a good compass, this is difficult to do, with a not so good one, it is pretty easy. You can compare how fast different compasses are.

This being said, if you are hiking and not running, a normal compass is by far stable and fast enough for you, and they come at half the prize. While hiking, I doubt you would notice the difference, I am myself not using my best compass for hiking.

So what do I mean by a 'normal compass'? A normal compass has a transparent rectangular base plate, made from some hard plastic, a completely transparent compass housing, filled with some liquid, alcohol or oil normally.

There are a number of further enhancements: Some compasses have mirror instead of the long baseplate. This is to be able to aim more accurately. Actually, this is most convenient when you do a triangulation, a technique I haven't described in these pages simply because I don't find it very useful. My experience is that the improvement is marginal, and it won't help you much if you really need to be accurate. On some compasses you can preset declination, and though I haven't tried it, I think once you've understood declination, it is easy to correct for it.

Now, you may see where I am going: To a very simple compass. All you need is a compass that you can take a course with, and point at a distant object. Why so simple? Consider this scenario: You're hiking in the mountains, with a map and a compass to guide you. Suddenly, the fog is over you, and visibility is down to a few meters (Yes, I have experienced this happening in 5 minutes). These are conditions when you may have to trust your compass with your life. Say you are walking on rocky grounds, looking frequently at your compass to keep the course. Suddenly you fall, and the compass is crushed in your hand.

Fortunately, as long as the compass needle is reasonably intact, a compass will still serve as a compass, and there is a good chance the needle will have survived the fall. Now, the first thing that happens is usually that the housing is punctured, so that the liquid pours out, or there may be a big bubble. This will make the compass a lot more unstable, so you may have to stand still for a long time to get a good bearing. The mirror some compasses have are nice as long as you have something to point at, but then, it isn't really difficult to navigate. Once the visibility is low, that is when it is really difficult, the mirror will not help you much. Additionally, a thick baseplate is more likely to have survived the fall than a mirror, and it is considerably more difficult to get a good bearing without a mirror or a long baseplate. So stick to the baseplate.

As a general principle, one can say that the more features something has, the more things can break (and as a corollary to Murphys law, it probably will...), and if you have made yourself dependent on these features, you'll be in trouble. Always learn how to cope without. Of course you may discuss this, but when something is as essential as a compass, the best way to learn to cope without nifty features, is to live without.

If you are considering buying a GPS unit, you should also consider the points above. I haven't used a GPS unit myself, but it is clear that it will open new territories for people who are not that good at navigating, which I think is very good. However, this is also a problem. There are many things that may render a GPS unit useless, among those something as trivial as a fall. A compass on the other hand is not that likely to be completely useless. The necessity of being able to navigate properly in difficult conditions without a GPS must therefore be stressed.

Many reviews of GPS units I have read give extra points to units with large displays and a intuitive user interface. I think however, that the display is probably the most vulnerable piece of the unit, and should therefore be as small as possible. Also, intuitive user interfaces are good, but of very marginal importance once you've learned to use the unit.

Let me finally introduce you to the compasses I use the most these days.

When I run orienteering, it is very important that the compass is fast and stable, and so, I use a quite expensive compass, the Silva 6 JET. It is a compass to attach to your thumb, it does not have a turnable housing, the typical use is a bit different from what I have described in the tutorials, as it is not so useful in course setting (and not that accurate), but extremely useful in keeping you oriented. I find it very good, and it has a very fast needle.

The other compass I use frequently is also a Silva compass, the Silva Starter which seems to have been replaced with the Silva Field. It is a very simple compass, made for beginners, really and should be quite inexpensive. I use this when I'm hiking.

In addition to these compasses, I've been using Suunto compasses a lot (they have a website, but it is so poorly designed it is inaccessible), and find them good. As previously noted, it was the russians who came up with the new good compasses. Silva bought their recipe imidiately afterwards for their JET series. A number of small russian companies sold very good compasses just after this happened, but few seems to have survived. I have tried one compass of MosCompass (site mostly in russian, on a slow server), and from what I can tell, they are good.

What you should go buying would depend on the issues discussed here, and what is available in your store. I would recommend looking around on the above pages and see how compasses there look, and try to find something similar.

So, what should one pay? Naturally, I have only experience from around here, and a fast orienteering compass would be about 500 Norwegian Kroner (check out the Exchange rates). A good hiking compass would cost about NOK 200. In the US (most of those who e-mail me are from the US), I guess $25 and below would be a reasonable prize for a hiking compass.

Kjetil Kjernsmo © 1999

kjetikj@astro.uio.no