Questions tagged [compasses]
Compasses are a navigational instrument utilising a magnetized needle giving a frame of reference based on North, South, East and West, as well as their intermediate directions such as SE, NW etc. This is based on Magnetic North, and not True or Grid North.
49
questions
3
votes
1
answer
180
views
How do I correct for magnetic declination?
I have a question about magnetic declination as it pertains to its use with compass navigation.
I currently live in Albuquerque New Mexico which currently has a magnetic declination of 8°E.
Let's say ...
- 31
8
votes
1
answer
293
views
Can anyone recommend a compass that doesn't develop a bubble at high altitude?
I have three compasses and each developed bubbles at 4000m elevation (photo below).
Even the nifty Suunto had a bubble on the first trip. The best was the Silva (on the right of the photo), which ...
- 181
4
votes
1
answer
224
views
Is this a valid method from taking a bearing from a map?
I want to check my understanding here. The goal is to determine your direction of travel by taking a bearing from a map using a compass, given that you know where on the map you are and where you want ...
- 43
2
votes
1
answer
447
views
What purposes does a physical compass serve better than a compass application on my cellphone?
I have an Iphone 12 which has a compass app. I've tried it out against city streets that have a known directional angle and it seems to be accurate. But the paper map orientation course still wants ...
- 2,977
0
votes
1
answer
104
views
Where can I purchase a quality compass? [closed]
I've signed up for a paper map orientation course and one of the prerequisites is to purchase a compass. The course itself recommends multiple models such as MC-2 from Suunto. But if I check the ...
- 2,977
4
votes
2
answers
299
views
If you have figured out one compass direction, is that always/sometimes/never enough to tell all the other three as well?
For a long time, I've been wondering for myself: if I know for sure that a certain house has this wall facing West, and I'm standing facing the wall in front of me, and I have nothing else to go by, ...
- 49
4
votes
2
answers
215
views
Silva Polaris compass, use of the second dial numbered from 0 to 7
I am looking for the use of the second (outer) dial numbered from 0 to 7 on the Silva Polaris compass.
This second dial rotates independently of the inner dial.
- 43
4
votes
2
answers
215
views
How to explain unexpected success following a bearing taken from an iPad
I live in northern British Columbia where the relevant declination values are currently
Magnetic declination: 17° 45.30' East
Grid declination (for Natural Resource Canada's NTS maps): 16° 17.04' ...
- 657
6
votes
1
answer
2k
views
What are the differences between prismatic, lensatic, mirrored, and optical sighting compasses?
Background
I am looking at compasses for backpacking and camping, and have come across more compass varieties than I had ever thought possible. Three terms that often come up together are "prismatic",...
- 1,885
8
votes
7
answers
3k
views
Is there an easy way to remember if you add magnetic declination to magnetic bearings or true bearings?
For some reason, once in a while I get confused if you add magnetic declination to magnetic bearings to get true bearings, or if you add magnetic declination to true bearings to get magnetic bearings.
...
6
votes
1
answer
409
views
How do simple compass needles remain level instead of see-sawing with magnetic dip? Are they flat even near the poles?
This instagram post by Colin O'Brady (just hiked across Antarctica) shows his compass needle looking fairly level, but I can't see enough else to know if he's holding it level.
A significant fraction ...
- 981
9
votes
5
answers
749
views
When using a compass, why not follow a degree mark without rotation?
Instead of taking a bearing the "official" way, why not just see what degree mark corresponds to on the direction I want to go (in real life or on a map), and follow that degree mark? That is, why do ...
- 91
8
votes
2
answers
253
views
What is head/lift indication in a digital compass on a sailboat?
A simple explanation would be great.
I am reading a manual for digital compass and there is a paragraph with the following words:
The SpeedPuck automatically detects when a sailor is trimmed to a
...
- 183
1
vote
1
answer
340
views
Are there bubble free handheld compasses?
We have one question asking where it is normal for a compass to have bubbles and another asking why compasses get bubbles, but we do not have a question clearly asking if handheld compasses exist that ...
- 69.2k
4
votes
1
answer
3k
views
Why do compasses develop bubbles?
Please note I am not asking 'in what conditions some compasses can develop a bubble', what I am asking is, why can't manufacturers make liquid filled compasses that will not, ever, develop bubbles. ...
- 251
5
votes
2
answers
434
views
Handheld Compass Triangulation Typical Error Range
I understand that there are a lot of factors that add to the error of a bearing and therefore the accuracy of a triangulation but I would like to know in general how accurate it is possible to be.
...
- 721
6
votes
4
answers
842
views
Offset in compass
I have a Brunton Truarc 3 compass. At the time I bought it I wasn't aware about declination settings or navigation basics. But recently I realized that it has offset of a few degrees (around 6 degrees)...
- 389
6
votes
2
answers
302
views
How to take a bearing when the geographic coordinate grid is not aligned with true north on a map?
I am confused by my new map of the Westfjords of Iceland. The geographic coordinate grid is rotated slightly, but the map indicates that true north is still the top of the page.
What's going on? I ...
- 163
9
votes
2
answers
2k
views
What is dead reckoning when navigating with a map and compass?
There is a technique for navigation known as dead reckoning, what is this technique exactly and when would it be useful?
- 69.2k
4
votes
2
answers
229
views
Can you find your location using the angle between compass bearings?
Sometimes compasses are less accurate than we would like them to be. They can be thrown off by their surroundings, have their polarity reversed, become demagnetized, develop air bubbles or be taken ...
- 69.2k
1
vote
2
answers
489
views
What is the minimum knowledge to navigate with only a compass?
Assuming I have memorized the major Latitude and Longitudes as they relate to the world, as shown in the image below and that I know how to identify latitude & longitude with a compass. What else ...
- 30.3k
7
votes
2
answers
9k
views
How to identify latitude & longitude with a compass?
I am not exactly sure where I am in the world. It could be that I am in a boat on the ocean, been in a plane crash, or suffered some other calamity. In any case I either have a compass with me or ...
- 30.3k
8
votes
1
answer
1k
views
I have a compass but no watch, how can I tell when it will get dark?
I was reading all of the answers to Are there any situations while backpacking that would require a watch? and surprised at the number of answers that said you need a watch so you would know how long ...
- 30.3k
12
votes
4
answers
2k
views
Are there types of compass other than the regular magnetic one and the gyrocompass?
Today I learned about the existence of the "gyrocompass".
A gyrocompass is a type of non-magnetic compass which is based on a fast-spinning disc and rotation of the Earth (or another planetary body ...
- 129
40
votes
4
answers
5k
views
Compass compatibility: Can I use my US compass in Australia? [duplicate]
Background
I bought my compass in the US last year. Next week I'm going to travel to Australia.
Question
Is my US-compass compatible with Australia? or do I need a special compass?
Do I need an ...
8
votes
4
answers
5k
views
Can a compass be thrown off by its surroundings?
Would it be possible for a compass be affected by its surroundings, such as a large iron deposit or other rocks to the point where it is not working correctly?
I am not talking about declination but ...
- 69.2k
7
votes
1
answer
2k
views
Can a compass reverse polarity?
Can a compass have its polarity reversed so that the end marked "north" points south and vice versa?
If so, what could one do to prevent and fix this problem?
- 69.2k
15
votes
2
answers
4k
views
Is it normal for a compass to develop an air bubble at high altitude?
I live in Denver, Colorado. Going above 10,000 ft. (3,000 metre) always results in an air bubble large enough for me to want to tilt the compass to prevent the bubble from interfering with the needle....
- 683
6
votes
3
answers
455
views
Making a compass from magnet and needle -- which end is north?
I was watching one of those Discovery Channel wilderness survival shows last night and one of the "survivors" made a compass from a piece of wire tie and an earbud's magnet.
He stripped the plastic ...
- 291
7
votes
1
answer
433
views
Should orienting arrow and meridian lines be parallel on a compass?
I recently bought my first compass, a SUUNTO Spiegel- und Peilkompass MC-2/360/D CM/IN NH, black.
I observed that the red orienting arrow and meridian lines are not parallel. They are forming an angle ...
- 173
30
votes
2
answers
10k
views
Will a compass work underground or underwater?
Because they rely on radio signals, GPS units generally do not work underground or underwater, but what about a plain ol' magnetic compass? Are the magnetic fields of earth present at all depths? ...
- 700
11
votes
4
answers
6k
views
How dependable is a cheap compass?
I was reading the BBC news today and there was an ad for an inexpensive "5 in 1 Outdoor Survival Gear Escape Paracord Bracelet Flint / Whistle / Compass / Scraper"
I clicked on the link and saw this ...
- 30.3k
12
votes
1
answer
2k
views
Should you store a compass flat?
My girlfriend keeps hanging my compass on the wall. Is this doing it any harm?
user2766
27
votes
3
answers
10k
views
How much distance is there between True North and Magnetic North Poles?
This question is not as simple as it seems, and a few minutes of googling did not drop the answer in my lap.
A comment at I never adjust for true north. Is this bad practice? suggesting that:
...
- 30.3k
52
votes
6
answers
9k
views
I never adjust for true north. Is this bad practice?
This question (Calculate true north with a compass and map) got me thinking. I rarely bother adjusting compass bearings for magnetic north. Is this bad? I understand the theory but I just rarely ...
user2766
12
votes
3
answers
3k
views
Calculate true north with a compass and map
We've a map and a functional compass. A compass shows of course the magnetic north and the map provides us with the correct and current declination.
The North Magnetic Pole is the point on the ...
- 23.5k
7
votes
1
answer
172
views
Most accurate way to judge distances traveled in a kayak?
I like to make maps in my kayak, so I need to know how far away I was from the last point, so the only way I know of is dead reckoning, and being in kayak its not that accurate.
So my question is: Is ...
- 529
12
votes
2
answers
413
views
How did cartographers map out shores before modern times?
I was down at high rock lake N.C. and I was making a little map of the shore lines in my kayak, or at least going to. I ran into a problem, I could not judge the distance from the last mark I made to ...
- 529
16
votes
3
answers
510
views
How did people make topographical maps in the pre-modern?
I've been getting into making maps with compass and a ruler and just triangulating positions of objects. I would like to start making topographical maps but how?
How did they make them before the ...
- 529
21
votes
2
answers
6k
views
Can a compass needle become de-magnetized over time?
My compass has become increasingly untrustworthy. Over the past couple years I had noticed that it often pointed pretty close to magnetic South, but it corrected after a light tap.
In two recent ...
- 1,448
11
votes
1
answer
519
views
Taking and using bearings
How would I go about taking a compass bearing of a distant peak and then relate this to the information on a standard map?
user2766
15
votes
2
answers
11k
views
How easy is it to magnetically destroy a compass?
I have quite a lot of items with built-in magnets in my backpack, like a mobile phone, an iPod or headphones. How easy is it to destroy my compass by putting it too close to these items?
- 4,983
10
votes
1
answer
4k
views
Is a compass generally accurate in only one hemisphere, or both? [duplicate]
Possible Duplicate:
Navigational gear worldwide
I'm not that well travelled (never been outside of Europe!) but at some point I'd love to head elsewhere to perhaps hike somewhere a bit more ...
- 22.5k
13
votes
1
answer
215
views
Magnetic deviation at either pole
I know that the magnetic north is not exactly at the polar north, so when hiking very close to the Northern Pole, you have to take the difference into account.
This got me thinking: Is this also a ...
- 1,035
13
votes
3
answers
796
views
Navigational gear worldwide
Is there any difference in navigational equipment between the northern and southern hemisphere? We live in the northern hemisphere but will be emigrating to the southern in the next few weeks. We'll ...
- 555
12
votes
1
answer
907
views
What should I look for when buying a Lensatic Compass
Lensatic Compasses seem to be priced from $5 to $100 USD. What features should I look for when buying one?
- 3,041
16
votes
2
answers
2k
views
What things should I look for when buying a compass?
Compasses seem to come in all shapes, sizes and (especially) prices! What sets a good compass apart from a bad one and what are some good characteristics to look for when making a purchase?
- 22.5k
30
votes
10
answers
6k
views
How can you navigate / determine your location in thick fog?
Are there any good hints, tips and ways you can use to navigate around and find your location in thick fog (apart from a GPS)?
- 22.5k
49
votes
10
answers
5k
views
How can you navigate without a compass or GPS
What are the ways you can navigate when you don't have a compass or a GPS? For example how can you tell which way is north.
- 591