Use a Lensatic Compass with a map & without

Either with a map or without, using a Cammenga Lensatic Compass isn’t difficult. This video gives a brief introduction to the (civilian) use of Lensatic Compasses.
See here for a no-maths way of setting the declination
• Cammenga compass - how...

[@mhmt1453]

This is what I was taught to use in the US Army (before the advent of GPS). It was a valuable skill to master, and armed with a lensatic compass and a map, one could effectively negotiate any terrain, direct fire upon a target, or effect a swift exit from an area. The maps were graduated into 100 meter grid squares, and with a compass one could further narrow that down to a ten meter square. We also kept pace counters (one could use pebbles or beads as well), and with practice, soldiers learned how to gauge distances travelled.

[@petesheppard1709]

And no batteries to fail! 😉

[@doonhamer252]

up until a couple years ago .I taught Hunters scouts, soldiers, prospectors and geologist trainees .. in map reading and navigation in Canada from the West coast to the high Arctic to Labrador .. for here .mag dec is vital to know and to set .. Canadian Gov maps have a scale on the side of the map.. given a fixed dec, and date recorded and the number of degrees that it varies per year.. you calculate the date then to now add the number of degrees it changes per year multiplied by the years, adjust compass .. Too often hunters and hikers especially find electronics useless .. especially on cell phones .. It's one thing to read an OS map and hike from one sheep pen to farm to lake .. another to travel 20 odd km in the bush without landmarks .. I still have my issue compass, but prefer my silva .. and or Brunton pocket transit

[@ericktamberg670]

GPS is very useful, but much more prone to fail and makes the brain lazy. Youngest people are too dependant of modern technology. As a police officer assigned to Missing Persons Unit of São Paulo Police, Brazil, we often need to locate lost hikers in jungle areas between our city and the South Atlantic. No signal of radio, mobile phone or GPS in some areas. Only the good old compass and map works. Sometimes I carry even boat flares to keep contact with our Tactical Air Service (police helicopters, aka "Pelican Units").

[@eddybear771]

& it's still a very valuable skill. I carry a GPS when hunting, but I NEVER leave for a hunt without my maps & compass. Taught my kids, & been teaching my grandkids, which has been a challenge since they believe technology is the only way, but they're slowly catching on & having fun doing it.

[@azure6392]

Just don't give it to a lieutenant

[@petesheppard1709]

IMPORTANT for those new to compass land navigation!! When following a bearing cross country, 'drift' needs to be accounted for. You can move sideways while keeping on the same bearing, so a good idea is to alternate the direction you go around obstacles; right, left, right, left. If you go around the same way, the tendency to drift off in one direction is magnified, even if the actual compass bearing never changes!

[@doonhamer252]

Also, geological variation can take place, I've worked in Indonesia, Canada Bush and Sub Sahara.. prospecting ( mineral exploration ) or security .. Sometimes you must be aware that Rocks containing high Iron and Magnetite ..can swing compasses quite drastically, and If suspected generally good practice is to ensure that you have a decent fore and "back" site .. try to never aim at one single object, always if possible try to line up two or more aim points. Obviously, the situation and methodology will change depending on the requirement whether rec, or tactical.

[@twoowls4469]

This is, bar none, the finest explanation of the lensatic compass anywhere on the net. Thanks for sharing!!!

[@TheMapReadingCompany]

Wow, thanks!

[@jennifernichols9468]

As a United States Marine I can say this is the best example of using this compass. Semper Fidelis from Texas

[@TheMapReadingCompany]

Thanks. Much appreciated.

[@inky4763]

This is the clearest and most useful video on the Cammenga I've see, and I've watch loads of them. Thanks

[@TheMapReadingCompany]

I'm glad you enjoyed the video. On a course last week in south England (The Chiltern Hills) I was showing the participants lots of different types of compasses and I was asked how to use a lensatic with a map. So I thought I’d make a video showing one method. I know lensatic compasses have been covered in many videos but not many of them show how to use it, simply, with a map.

[@inky4763]

I like the Cammega, but if I'm honest, I like it more as an object than as a practical compass. That said, your video shows it can be used effectively with a map and without a protractor. But is it really worth the hassle? Do you think it actually has any navigational advantages over a baseplate or mirror compass?

[@TheMapReadingCompany]

The Cammega 3H is a really good compass that’s built for a very specific group of people to use (just like the Barker M73). For this it needs to be able to operate in very rough conditions, so I imagine that why it’s made like it is. The method of using it which I demonstrated on the video is fine for what I need it to do - to be used by walkers and trekkers. It’s not as precise as using a protractor, but we (walkers and trekkers) don’t need to be. There obviously are times when those who the compass is designed for would need to be very accurate when passing on bearings to others, who may use them in very serious situations. I tend to use just a very standard base plate compass, as that’s what I’m used to. If someone learned to navigate using a Cammega then I’d guess they will also continue to do so. It doesn’t make much difference which compass you use as long as you’re able to use it to navigate safely.

[@laymansview5246]

@@TheMapReadingCompany You should do a video on using an analogue watch as a compass.

[@joseelempecinao89]

I was in the army. I do remember how complicated the orientation lessons seem to me those days. True the army ask for a lot o things more, but it would have been wonderful to start with the basics with somebody so pegadogic and clear as you. Thank you very much fo the refresh.

[@mikeellis2025]

I was in the army and going through Primary NCO Academy, PNOC for short. We did a night compass course, no map. You would get the azmithus to the next location and use the compass to get you there. You had to be precise as there would be 3 post with your next location and you had to be on the right post. The 3 post were only about 12 feet apart. If you got the wrong post you flunked the compass course.

[@TheMapReadingCompany]

Hi Mike, That's really interesting. Thanks for joining the conversation.

[@asmith7876]

Same thing…except it was in Boy Scouts, if you followed it all correctly there’d be a bag of doughnuts in a tree 😂. 10 years later in the Army learning landnav in the desert I was happy for the Boy Scouts.

[@doonhamer252]

More or less the same thing .. Also when I trained exploration crews in survey grid and claim staking etc, back before click (online/paper) staking became the norm in Canada. We set out a system of 1 km square (no slope correction) We then after the basics of sighting and use of compass set declinations etc, then would set them off , each working from a common LCP . They had to navigate and correctly locate intermediate posts every 500 meters and make the 90-degree turn at 1km returning to the start point mock LCP (Legal Corner Post) which we removed when they left, they then place a ribbon where they thought they had to finish. Initialy very few were able to get within 50 meters of their correct point, some ended up several hundred meters away. Then We'd throw everything at them, changed the declination on compasses, place the grid on top of magnetite/sulphide outcrops (your nows knows) Given MRC is or was in SW England .. Sulphides and magnetic rocks are abundant..

[@laymansview5246]

As unit training NCO I setup courses like that along with other land nav courses.

[@BCVS777]

NOTE: For those who wear glasses; the metal in your glasses can interfere with the arrow when you put your eye up to close to take a bearing. I have found that my Cammenga is affected by 2-3 degrees so I remove my glasses before sighting thru the lens.

[@ericktamberg670]

Other items can also interfere, like helmets, dog tags ans even orthodontic appliances!

[@SavageVoyageur]

You are correct sir. I had glasses that had sunglasses that clip on the main glasses. Guess how they were secured? Thats right magnets. So I was getting wrong readings when I was wearing my glasses. Made it hard to get readings without glasses on.

[@scotty5717]

I'm learning a little every video,I'm even going through the previous videos.great education

[@TheMapReadingCompany]

Thanks, I really appreciate your comments.

[@dennisss3974]

Great memories of my dad. I was in Boy Scouts and we were doing navigation. We had some kind of funky map and cheap compass. I showed my dad, he went down to "his trunk" where he kept his old army stuff and gave me his lensatic compass. He asked if I was serious about finding my way in the woods. We went to Appalachia Outfitters and he bought some topo maps. We went into the woods one time and the first thing he asked is where are you (an important point in navigation). Find it on the map. We drilled and drilled and I can say I'm pretty confident in my navigation, until I get lost

[@kiloalphasierra]

I personally am never lost. I always know exactly where I am. I just may not know where that is in relation to where I want to be!

[@Gruin]

Always Enjoyed the Phrase, "Be Here Now" Now With a Map and a Compass, I Can Put My Finger On the Map, An Logistically Say, "Be Here Now." Tnks

[@joezephyr]

The correct phrase is: Never truely lost! 😁

[@Rustebadge]

Great. We used to use these and baseplate compasses in Boy Scouts in the US. Great fun and I miss it. Thanks for the info and memories.

[@gadaxara3593]

It is essential to know how to use a compass for the infantry soldier or a sextant for the seaman. There is GPS now, but one day it may be neutralized by an electromagnetic event, and you have to know how to navigate the old way.

[@davidrigert2649]

I trained with this compass back in the 80’s, thanks for the refresher.

[@markmiller9838]

Thanks for a great video. I've had a Lensatic compass for more than 50 years, inherited from my dad. I had no idea about how to use it or the purpose of each of the parts. While I may never get to use it 'in the wild', I really appreciate knowing what it is and how to use it. Mark Miller, Canton, Ohio USA

[@TheFatCottonwood]

I've had a version of one of these compasses for years without knowing how to use it, there are also some peaks I would like to Identify in the distance from my house. This is really awesome, I believe I already have the maps as well. In New Mexico, there is always a mountain range in the distance, this would be a cool road trip distraction, identifying distant land marks and ranges.

[@Counselor77]

Very good video, detailed and informative, and never boring.

[@roberttakatsu3926]

It's hard to believe that people still use a compass and a topo map. I learned this skill in the boy scouts there was no GPS. That was 50 some odd years ago. I'm glad the skill is being passed along. In Canada it was considered essential

[@petesheppard1709]

Yeah, GPS is wonderful, but if the batteries or signal die...well, I hope they know their terrain.

[@robinj.9329]

My friends that are very active in my States "Search and Rescue" Units tell me it is VERY COMMON to "Rescue" lost hikers/hunters who have a GPS with DEAD BATTERIES 🔋 or trying to use just some free GPS app they got for their cell phone! The "Moral" being....... There is simply NO SUBSTITUTE for map, compass and THE SMARTS TO USE THEM !!!!!

[@thormusique]

Your explanations are wonderful, cheers!

[@doonhamer252]

well done video and tutorial.. I agree about mag dec, especially in the UK as the variance is minimal and you are more likely to observe a fixed feature that will correct your course ..

[@peterbogart4531]

T Y, Sir! Never had the 3-degree increment on the bezel explained before. I have a lensatic without a manufacturer's label. Takes forever to settle compared to a Silva baseplate, but is very useful when set on top of a stable surface.

[@Crusty_Camper]

That's a useful video. Something I have found when following a bearing is not to try and walk while watching the dial. You can easily crab off to one side or the other while keeping the needle spot on. What works for me is to find something identifiable on my bearing, walk to that, then repeat. It's quite accurate over significant distances.

[@byteme9718]

Really? Just how else do you think you'd use a compass?

[@Crusty_Camper]

@@byteme9718 Some people walk watching the needle while physically drifting off to the left or right as they go. The needle shows they are pointing the compass in the right direction but their travel on the ground can be way off.

[@byteme9718]

@@Crusty_Camper My comment was very clear, that's how you use a compass. Obviously no one ever taught you, if they had you'd have known that in the first few minutes.

[@Crusty_Camper]

@@byteme9718 Yeah, we seem to have our wires crossed. As part of a Mountain Rescue Team for the last 30 years, accurate compass use is an essential skill for me. My comment was aimed at the large number of people who don't know how to use one and we end up sorting the problem out for them. It was a suggestion, not a revelation.

[@petesheppard1709]

And alternating which side of obstacles you walk around also helps reduce drift.

[@donaldnaymon3270]

Great information. Thank you for sharing.

[@artcianfanojr]

good video. informative and concise

[@user-dw1qj9nc4u]

An easy way to do reciprocal directions. Instead of adding or subtracting 180°, you remember that any heading is three digits. The first digit can be 0,1, 2 or 3. (ie 60° is 060°). If the first digit is either 0 or 1, you add 2 to it and subtract 2 from the next digit. For example 180 becomes 360, 050 becomes 230. If the first digit is 2 or 3 subtract 2, from the first digit and then add 2 to the next digit. For example, 360 becomes 180.

[@shammon1]

At last a simple use explanation on a map close up great thanks

[@TheMapReadingCompany]

Glad you liked it!

[@ManyNex]

Really great explanation, thank uou very much for sharing this knowledge. I’ve never found a video so useful expecially to explain simply how to know “what am I looking at?!!”🤣 now I can finally look at a mountain top hiking on the Dolomites and know its name! Thank you very much!

[@TheMapReadingCompany]

To find "what am I looking at" try this video kzbin.info/www/bejne/poWxe4KmgciHas0

[@ManyNex]

@@TheMapReadingCompany just saw the video, immediately saved into my “Trekking Advices” playlist, I’m going to write down some infos you shared to keep them with me in my next trekking in case of need! Thank you very much for your kind advice!

[@stephenharvey7581]

Thank you so much I am on my way to understanding my new lensatic compass !!

[@wpherigo1]

Great videos. Takes me back to my Boy Scouting days, orienteering merit badge, camping and hikes.

[@razzo9610]

Another good presentation.

[@giorgiogarcanni6754]

Excellent as always thanks

[@americanwriter2533]

Great video! Excellent lesson! 🤩🇺🇸👍

[@davidcruz8667]

Not quite, when you sight a bearing to a feature, you line it up with the notch on top of the lens and the wire in the observation slot. Then you look through the lens, which is there to magnify the compass card, and read the bearing from the bezel markings under the black index line. Best way is to tilt the lens at a 45 degree angle and the compass cover straight up at a 90 degree angle. Two acronyms: for declination from Magnetic North to True North or Grid North on the map declination diagram, use LARS (To the LEFT, ADD the amount of degrees indicated on the declination diagram; and to the RIGHT, SUBTRACT); and for back azimuths, use the acronym LAMS (LESS than 180 degrees from the sighted bearing, ADD 180 degrees, and if your bearing is MORE than 180 degrees, SUBTRACT 180 degrees... For example, a bearing of 78 degrees, being less than 180, gets 180 degrees added to get a back azimuth of 258 degrees, and a bearing of 301 degrees, being more than 180, gets 180 degrees subtracted to get a back azimuth of 121 degrees). This is useful when plotting your position on a map from observable features: if you take a bearing from a water tower, a hilltop, any fixed point feature, you then draw a line from the feature on the map through your position using a back azimuth. You can plot your position using a resection with two identifiable features on the map, use a cross section to find a point along a linear feature such as a road, powerlines, or a stream, or use an intersection to obtain the location of an observable point from two different physical locations from which you shoot an azimuth to this feature. When using a map it helps to use a protractor along with the compass marked with degrees all the way around, and mils if you're using that scale (mostly military). People should be aware that the compass can be affected by metallic components on your body, so keep it away from belt buckles and other things while you use it. In the military it is very important, since we carry weapons, knives, binoculars, metal clips on our gear, snaps, lighters, bolt cutters, magazines, pack frames, camp stoves, trip wire, and many other things. Also, using a lensatic compass on slopes requires attention in order to keep it level, since a certain amount of tilt in any direction can provide an inaccurate bearing, even though the compass card seems to be rotating freely. Wobble it around just a little before you take a bearing so you can observe in which position it indicates that it is level with the ground and is pointing at Magnetic North accurately.

[@meditationsoundscapes5203]

good description. for more accuracy use a plumb line on the wire, as this compass has no gravity bubble

[@CristiNeagu]

Isn't that exactly what he said?

[@davidcruz8667]

@@CristiNeagu no, close, but a little off. Precision counts. Understanding each component counts.

[@CristiNeagu]

@@davidcruz8667You said "not quite" in relation to sighting a feature. What you said is exactly what he said. Care do detail what did you mean by that?

[@davidcruz8667]

@@CristiNeagu OK. One ergonomic detail: the angles of the lens and the cover are specific, the lens serves two purposes, as a rear sight when taking a bearing by sighting through the top notch, and as a magnifier for the numbers on the compass card under the black index line, generally set at approximately 45 degrees looking straight at the heading numbers; and thus the cover itself is set straight up at an 80-degree angle, with the sighting wire in the slot used as a front sight. Bringing the cover down greatly diminishes your sight picture, and can lead to errors by a degree or two. If you do this navigating in thick brush for an extended period, you can end up off track by several miles. Bad juju.

[@piorommeldasal]

The best tutorial!

[@CFWaittoleave]

Well done again and very much appreciated. 16:23

[@hamishmacbeth4292]

Simple straightforward tutorial, it’s good to know that the compass is still being used. Its a good skill to have when out and about it’s so much more interesting then using and relying on GPS, in my opinion. I still insist on using a Compass, Prismatic mainly it’s so easy to use. My way of remembering how to add or subtract was a way that had been taught to me many years ago was this. Grid to Mag Add and Mag to Grid get rid and any variations that the Map might have, would be adjusted accordingly. Just subscribed. 👍

[@richardhelger858]

Nice) thanks for a proper explanation. Now I need one of these )))))

[@mikeneale2459]

EXCELLENT! THANK YOU!

[@dbernstein7901]

If you take a bearing to a distant object the declination still remains an issue presuming any reference to that point on a map with N at the top. So the true bearing has been corrected from the compass magnetic reference. Only then can a true back angle be determined.

[@katjasandelin]

Thank you for such a clear and good teaching! 🙏🤗

[@TheMapReadingCompany]

I'm glad it was helpful!

[@paulmicelli5819]

I learned how to operate this back in 1968 while training with the US Army at Fort Ord, CA.

[@michaelnelson7572]

My best friend's father was foreman at stocker&yale that had the DOD contract for that style of compass thru the 70s

[@petesmith9472]

That is a northern hemisphere model. There are a couple of pre use steps to take to Normalise the compass for southern hemisphere operations

[@charlessmyth]

That was instructive :-)

[@sleddy01]

I will need to watch this a couple times

[@WeiMinWu]

thanks for your help，this is a good guide

[@marc-andrebrunet5386]

Thank you sir

[@Indy1701e]

Great video! I only have a US compass rebuild, not the original german army one, but the system is the same!

[@jmarlow2153]

Reminds me of the OCS map reading exam at Benning in January.Very stressful.A few candidates didnt pass,even with retest.

[@petesheppard1709]

In the US military, using the compass to get a bearing to a specific object or point is (or was) called 'shooting an azimuth'.

[@jublywubly]

Thanks for making this very informative video. I grew up knowing how to use lensatic compasses, but it's years since I've used one, so I've forgotten a lot of it. I don't know how reliable that particular compass is, though. The company can't even spell metres correctly. 🧐

[@petesheppard1709]

For us Yanks, the spelling is quite accurate! 😜

[@carebears9010]

I actually still use compass 😊 they are very reliable unlike mobile phones what can lose signal or battery dies. I love going on adventures just setting my home cords then getting lost in the middle of nowhere land and then following the pointer all the way back home never fails unless you are totally lost then a map helps but still very useful tools

[@mariuszkalwer5278]

Great channel. I suggest doing a video about navigating by hiking and drawing your own map. The thing is that in Europe we have mountains covered with thick bushes ...often very hard to go through in straight line. You can basically walk where it is possible. Not like you british guys....nothing but open space :-)))

[@tomwinstanley1915]

It's worth mentioning that the tritium lights have a half life of 10 t0 12 years. Thereafter, their function falls off rapidly. For civilian use the phosphorescent version is better and slightly cheaper.

[@matthewk6731]

When I was very young, my father gave me his USMC watch and compass, both of which I soon lost while playing around the neighborhood. Arrrgggg!

[@C-Mo_PuraVida]

Spot on mate. Thank you for the video. You answered all my questions and made it simple and easy to understand. Right on man. - Chris Beaverdam, Virginia. USA

[@TheMapReadingCompany]

Glad it helped

[@mikeadler434]

👍👍

[@Brood_Master]

I might have missed it but I never heard an explanation for how to set up the map... the map needs to be oriented to north prior to using the compass. I personally set my map up to account for magnetic declination so everything is a straight forward transfer whether reading from or to the map...

[@TheMapReadingCompany]

It isn't advisable to try and orientate a map to account for declination. You should adjust your compass.

[@giovannidigirolamo2740]

Is it more accurate to use compass or protractor to get azimuth? I was taught how to use a protractor, this way looks more simple.

[@TheMapReadingCompany]

Hi Giovanni. Yes you can use a protractor or a compass. Both methods are accurate - if the person knows how to use the equipment. Protractors can be used by people who need to only use a map (for example surveyors) to create plans or diagrams. They are also used by people who have a compass without a straight edge or some military situations would be better with a protractor, etc. On my navigation and map reading courses I would always suggest using a compass to take your bearing/azimuth. This way you only need one thing (a compass) and you don’t need to draw lines on your map.

[@senatorjosephmccarthy2720]

And if you're near a building, car, or anything that might contain steel, move away from it before using the compass. Steel effects the compass needle magnetic tip.

[@chrislnflorida5192]

This video at least u explained where to get the declaration (sp) on the map. Now when your siting in your compass, where do u set your degrees??? East is least -, West is best +.

[@Allan_aka_RocKITEman]

@TheMapReadingCompany >>> FWIW, I have one of these compasses. From a young age, I thought lensatic compasses were 'cool'. Same for the tritium glow tubes. Also, I have had other things {magnetic compasses, wristwatches, etc.} that used luminous paint. They never seemed to 'glow' for long enough to be useful. The tritium tubes solve that problem.

[@jamespadeljr007]

I'm your follower and all video you had are very informative but in 13:27 on the video made me a little bit confused. Is there no need to align the north arrow of the compass to the north line of the map? Thank you for the answer.

[@JCJ7754]

Great video, I fancy trying a prismatic for my self, can't justify the Cammenga price, what do you recommended as a budget alternative?

[@rudychavira5558]

Sir can you set declination east or west prior to doing this?

[@TheMapReadingCompany]

No you can't, not with this compass

[@rudychavira5558]

@@TheMapReadingCompany what about the Silva type mirror compass?

[@TheMapReadingCompany]

It depends if it has semi-permanent declination scale. see here: kzbin.info/www/bejne/mpjZiKGpoKaZrsk

[@markeslinger7051]

I just saw on the comenga website they have a baseplate compas with the same dial as the 3 h. Not seen videos on it yet

[@TheMapReadingCompany]

The Cammenga Destinate (their base plate compass) is one of the videos in my "Three Minute Gear Review" series of videos. I've done about 15 up to now. I'll post them when I have about 20, to see if anyone watches. If they do I'll make more.

[@oasacademy4953]

Very good tutorial, but is there not a way to use it to work out where on a map you are? If you can take 2 bearings?

[@TheMapReadingCompany]

Yes there is. You can see how it's done on these two videos: kzbin.info/www/bejne/poWxe4KmgciHas0 kzbin.info/www/bejne/bGLYfp6sZp6Ir9k

[@cz503]

What's best compass for the money in US market? Thanks

[@TheMapReadingCompany]

Sorry, but I never give advice on which is "the best" compass, as they are designed for different uses. As an example, if you navigate at night you'll need one with the highest possible contrast and black text. If you're in the military then mils will be simpler for range finding. If you're on a budget then you'll need to look at how much the compass costs. If you're navigating over longer distances then a mirror compass would be more appropriate than a base plate. If you're mountaineering, as opposed to trekking, then weight will be a factor. A large magnifying area will be important to some people. Multiple roamer scales may be needed for some types of trips.. Etc. Etc. So the best advice I can give is to look at what will be the primary use of the compass and then look for a compass with the features needed to make it as simple as possible to use

[@TheDe1deonly]

Still have mine from 1976, USAF TACP ROMAD...

[@MrDidaxi]

How does one know what the magnetic declination is, for a particular area?

[@MrDidaxi]

Forget my question; I just read that it is supposed to be indicated on the map.

[@ericktamberg670]

The simpliest way is the shadow and stick method. You can fix a 1-yard stick vertically on the ground and mark the two shadow tips after 20 minutes. The line traced from one mark to other gives you the true west-east line. Align the compass base with the west-east line to get the true north and magnetic declination.

[@nospoon4799]

Hey I remember maps. And that spinny thing with a magnet in it. lol

[@user-rz6fu7un9z]

quick question, are there any markings or any way to tell if your military compass is for the northern or southern hemisphere or are military compasses global compasses. . . .

[@TheMapReadingCompany]

I don’t think so, but I may be wrong. If you watch the video I made you can see that my Cammenga compass has only three sets of numbers, none of which show if it’s northern or southern hemisphere. NSN 6605-01-196-6971: this is the US government’s National Stock Number 23 04 77: Manufactured year = 23, month = April and the Lot Number = 77 (77 means it wasn’t made for a US government order) 21-26480-03E: this is just Cammenga’s licence number from the US Government and the 120 mCi is part of that licence and it shows how much tritium can be put on to each compass.

[@TurboLoveTrain]

You loose some accuracy if you take a northern hemisphere compass to the southern hemisphere (or vice versa) because of how the needle is weighted (How much accuracy you lose is related to the quality of the compass and user skill). A cheap northern hemisphere compass may bottom out on a flat surface in the southern hemisphere--again because of how the needle is weighted. You can tell just by looking at it easily: If you set it on a flat surface and the needle platform is also flat: you have the correct compass for your hemisphere (or a global one). If the needle dips significantly even though the compass is flat: you're using a compass from the other hemisphere. The MILSPEC compasses will tell you in the technical specifications but odds are very high it's going to be northern hemisphere if it says "made in the US" on the label.

[@TurboLoveTrain]

@@TheMapReadingCompany Milspec compasses are expected to be global. These use a deep well to overcome hemisphere dip even though they're usually balanced for the northern hemisphere.

[@Dog.soldier1950]

These are the USMC issue. Bullet proof. Mine is from 1983

[@rafikbarseghian912]

Are we going to have the same number when we shoot the baring with baseplate compass and lensatic compass?

[@TheMapReadingCompany]

Yes. The type of compass used has no effect on declination. But it depends on the type of compass being used and the skill of the user as to how accurately it can be adjusted.

[@darkcode9794]

Very useful video for the soldiers 😂❤

[@daniellyne1]

May I ask a stupid question please, what is the difference between minutes of aglngle and degree or are they the same thing ? If not how do you work it out

[@TheMapReadingCompany]

It's not a stupid question as both are fractions of an arc. A circle can be divided into 360 “segments” (AKA degrees) each segment can be divided in to 60 smaller segments, called minutes and each of those minutes can be divided in to 60 tiny segments called seconds. If you have an angle which is centred at the middle of a circle (so the two sides of the angle and the center of the circle are at the same point), the length of the arc (the bit of the circumference) formed between where the lines cut through the circumference of the circle is known the minutes of arc (AKA minutes of angle). Normally shooters use minutes of arc/angle as it make calculations simple. e.g. a minute of arc/angle at 100yards is about (to within 0.047) an inch. ** To an expert there is a different to ordinary people like me and you, basically they can be used to mean the same thing.

[@daniellyne1]

@TheMapReadingCompany thank you so much as I've said I really appreciate your effort you put into your channel , and thank you for explaining this . Looking forward to your next video kind regards Daniel AKA ( Dan The Outdoors Man)

[@ButchCassidyAndSundanceKid]

Does the lensatic compass work in the southern hemisphere as well as northern hemisphere ?

[@TheMapReadingCompany]

It won't work in the North AND south, but in only the North OR South. I think (but may be wrong) that the default is a Northern Hemisphere compass but you can pay a small suppliment when ordering for the Southern Hemisphere option.

[@ericktamberg670]

@@TheMapReadingCompany , I heard about it. In my country (Brazil), we are rarely warned about this difference. Most people uses compasses made in China, and only Silva and Suunto has dealers in Brazil that offer "global compasses". Our main problem with US-made compasses are the map reading scales: many are graduated in feet or miles, like a Brunton Eclipse Pro that I have (totally useless here), but the standard 1:25000 or 1:50000 is very useful. I never paid attention to "North" or "South" Hemisphere calibration (indeed, I never had or saw a compass specified for South Hemisphere), and American, Chinese and Japanese compasses always worked here (about 23°S 46°W). Could you explain it better, please?

[@thudor1]

The Cammenga 3H is the one used by the U.S. Armed Forces.

[@StarWarsJay]

I remember at school we all had to learn how to use a compass and went orienteering a couple of times a year. God knows what kids these days would do if the internet went down.

[@simongee8928]

I still have my dads WD issue prismatic compass which works on the same basic method as the lensatic. The dial has a hand operated lock which lifts the dial slightly and puts the scale numbers out of focus through the viewing prism. Most irritating - ! 😅

[@protonneutron9046]

Tritium or phosphorus is the same price for the US Mil compasses. Most people buy phosphorus as the tritium starts breaking down after ~10 years. Whereas the phosphorus lasts a lifetime. The military use tritium because they don't care if they have to throw them away (which they do) after that time.

[@asmith7876]

My tritium model is about 35 years old, still glows enough to be seen.

[@protonneutron9046]

yes, it varies by amount put in. The manufacturer only guarantees 10 years. See half life info@@asmith7876

[@Hootyhoo-jq9vq]

Are you familiar with the acronym, “LARS”? It is for declination diagrams. West being left, East being right. Simply remember LEFT ADD / RIGHT SUBTRACT. LARS. Its easy to use because the declination drawing either has the declination on the left or right of the Grid North line. I am dyslectic and I can only use memory techniques. Trying to think about declination in 3d would cause my head to explode.

[@TheMapReadingCompany]

I cover the LARS methods in this video: kzbin.info/www/bejne/ipeco6WjppqJnJo

[@massp0108]

Thank you so much for this simple explanation! But I do have one question...do you have to be actually on site to take a proper map bearing with a Lensatic Compass? I am practicing plotting bearings (at home) using a map & compass, and checking my numbers with Google Earth; but my numbers are off :( Even when I account for declination. Not sure what I am, or not, doing correctly. Going from a transparent baseplate (with alignment lines) to a floating dial with degrees, is a learning curve for me apparently.

[@TheMapReadingCompany]

Google Earth compass is not normally correct - I don't know why. I have just tested 5 different lines and they are all out by between 3 and 6 degrees. You don't have to be "on-site" to check a bearing - you can be anywhere. Remember that Cammenga say their compasses are only accurate to within 40mils / 2.25 degrees Suggestion. Take the bearing with your baseplate compass and then do it with your lensatic and see if you get the same results. If not then make sure (try to be accurate) that when you point the north magnetic part of the disk northwards, it really is pointing north.

[@massp0108]

@@TheMapReadingCompany Thank you so much for the reply! I don't know why I didn't even think of comparing the results with my Baseplate! And the very fact that there is a margin of error could play into my seemingly inaccurate results. Thank you again, really enjoy your videos. Watching them from the US, New York!

[@chriskelly4894]

He left a lot out. If your bearing to A is less than 180 degrees, eg 170 then 180 cannot be subtracted from it to get a back bearing to B as this would be -10. In that case you should add 180 degrees instead, eg 170 + 180 = 350 back bearing.

[@sethkinle2254]

I feel like the suunto mc-2 is better and easier to use. But these are really cool

[@-----REDACTED-----]

Could’ve also thrown in position triangulation since you were basically at it 😅

[@TheMapReadingCompany]

See here kzbin.info/www/bejne/bGLYfp6sZp6Ir9kfeature=shared

[@zachburns2495]

Does reí or any outdoors shops offer practice maps with markers that you can try to find using just the map and compass? I don’t really know where to start with navigation with no experience

[@TheMapReadingCompany]

Hi Zach I don’t know if REI does this. In the UK we have a charity called The Outward Bound Trust which offers excellent courses and also individuals (like me) who offer instruction at all levels. In the US some local mountain rescue teams offer basic navigation training so you could try contacting your local team about this.

[@TheMapReadingCompany]

Hi Zach - update. Maybe you could contact the US orienteering club as they seem to have groups all over the USA. I'm sure they would be able to help. orienteeringusa.org/events/clubs/

[@Jvk1166z]

so one question, if i've got no map, say it's been lost or destroyed somehow, and i see a feature i want to move towards in the distance. if i sight that feature, and read the bearing from the dial, if i wanted to navigate towards that, would i then set the tritium mark to be directly over the north arrow and keep it there? or am i misunderstanding something?

[@TheMapReadingCompany]

Look through the lens to find the bearing of the feature (let’s say it’s 123 degrees). Hold the compass and rotate it so that 123 is directly under the index line. Look for something which is along that bearing and walk to that AKA walking to the wire). When you arrive, again rotate the whole compass so that 123 is under the index line, then sight something else which is along the bearing and walk to it. Keep doing that until you arrive at the feature. Most of the time, once you have rotated the compass so that 123 is under the index line, it is common to rotate the bezel until the tritium mark is over the north arrow. This can make it easier to set the bearing again if and when needed. If you're walking at night having the tritium mark over the north arrow (which also has a tritium section) is the best way to sight your next move. But, the temptation then is that some people will try and walk along keeping the tritium mark over the north arrow as they move. This is not a good idea, as it’s almost impossible to accurately follow a bearing in this manner. It’s always best to identify something along the bearing and walk to it, then repeat. Keep doing this until you arrive at the feature you’re aiming for.

[@Jvk1166z]

@@TheMapReadingCompany ah, makes sense, basically just use the bezel mark to make it easier to find the bearing again, but walk towards landmarks along the bearing instead of relying on it while walking, thanks

[@angelmunoz3462]

How to work the dial is important, not the lens or the color , we need more explanation on the mark and the north how to use it, don’t worry about how to open the compass

[@williamkeith8875]

My compass is off how can I calibrate it

[@TheMapReadingCompany]

If your compass is "off" by more the 2 degrees it's not working. Contact Cammenge and ask about a replacement. I don’t know what Cammenga’s policy is on this and it may depend on how long you have had the compass.

[@williamkeith8875]

Thank you@@TheMapReadingCompany

[@oml81mm]

No compass is spot on accurate and easc and every compass will have it's own error. This "individual compass error (ICE)" should be marked on the compass somewhere. For normal map work and walking the error will be small enough to ignore, but for more serious use be careful. If you know what the error is you can compensate for it.

[@user-ml7do1ep1e]

Actually Once U understand and learn the Map 1 over 250 and 1 over 500.. And the Decklation it's easy to call Arty or Mortars in 🌠

[@equaliser2265]

Grid to Mag add Mag to grid Rid

[@greedygringoprospecting6941]

i have a brunton 9077.

[@Francois_Dupont]

fist step: buy a good reliable compass. ive had many and most are garbage. you better buy a good one like SUNNTO or like hes got here a Cammenga.

[@migranthawker2952]

Much better to buy a Silva compass with a sighting mirror which comes with a declination adjustment

[@TurboLoveTrain]

I hate that all the lensatic compasses I consider "good" are several hundred dollars which is an off-putting price for most beginners. I honestly believe relying on GPS for navigation makes people awful at navigation and, conversely, I've noticed the better someone is at using a map and compass the less they actually have to look at the map or the compass.

[@DavidMaurand]

don't USGS maps have declination? They used to...

[@guardali1]

Can someone please explain 9:22 in better detail?

[@TheMapReadingCompany]

Have a watch of this video. kzbin.info/www/bejne/p4mmepVjibN1g6c

[@alexanderharris9407]

What is wrong with working in magnetic. Nothing 😊

[@vigilantdr.dolittle]

I will never understand why folks need an explanation how to use a compass.

[@keithtanner2806]

That compass looks like an awkward form of marching compass.