How to calculate declination

The ability to calculate magnetic declination is a crucial skill for anyone venturing into the wilderness, especially for activities like hiking, camping, or navigating off the beaten path. Of course normally you can simply look on line but if you are in an area without internet access you will need to be able calculate the magnetic declination for the area with just the information on your map.
All the information required to calculate magnetic declination manually can be found on your map and, using some very simple maths, you will have a good idea of what the magnetic declination is for that area.
This skill adds a layer of preparedness and confidence for those exploring nature's less-travelled paths.

[@moorejl57]

If you are at a known location on the map, measure and log the grid north bearing to a feature on the map. Then take a magnetic bearing to that same feature with your compass and log. The difference is your declination. No need to make an estimated calculation based on the year the map was printed.

[@fernandotanco8744]

Thats correct, is the best way to calculate declination

[@KILLERPOLECAT]

You could do this from any two known points. Declination being the difference between the map bearing and the field bearing 👍🏻

[@chucktaylor89519]

If one were to calculate a bearing from two known points on a topographic map and compare that number with the bearing of the same two points read on a compass set to zero declination, would it be safe to assume that the magnetic declination is simply the difference between the two bearings?

[@fernandotanco8744]

Correct!!!

[@denisripley8699]

Hang on ! For a moment there I was thinking about Magnetic Inclunition.. which really is a black art.

[@TheMetalDetectingChannel]

Nice meeting you today on the hills pal!

[@TheMapReadingCompany]

And you guys. Just watched your video of when you found the gold. This must be the happiest face on KZbin when you found it. Everyone should watch this kzbin.info/www/bejne/r6iTfGSVbphgn80si=pZdoa4JBVmgEQMZc

[@David-if9vi]

Here is a tip that will help you. At 2:55, you have the change at 12' = 12 minutes per year. X 5 years will give you 1* degree of change. This will not cause much errors in your readings. Take your map, and a long ruler. Using the magnetic bearing indicator/direction. Mark the entire map with ruled pencil lines. You now have your magnetic lines, and you work directly from these. What also is as important is navigating using the contour lines.

[@davidbelding4995]

How confusing that the terms declination and variation are synonyms in America but also have quite different meanings depending on whether they are used in nautical navigation, land navigation or astronomy. As a mariner variation is the difference between true and magnetic bearings and declination is an angular measurement from the celestial equator used in celestial navigation. 🤪

[@darkporpoise]

It can be worth periodically "refreshing" the declination info on your old maps to keep them up to date. Only takes a couple of minutes and a sharpie.

[@TheMapReadingCompany]

Good idea 💡

[@stpetie7686]

Thanks for the upload and for something new to think about. Always happy to see another of your videos.

[@percyveer5974]

I have been watching you for a while now and you are without doubt my favourite KZbinr. I haven't understood one word you have said but I have thoroughly enjoyed it. Keep 'em coming 👏

[@mrparlanejxtra]

Buy yourself a Silva Ranger 3 compass and it will all come together and you will have a eureka moment

[@davemc1944]

What? No waffle? Or was it all waffling?

[@TheMapReadingCompany]

That made me smile. Sometimes the comments are better than then videos 😊

[@MountainHobbler]

Love this channel!!

[@mrparlanejxtra]

You do realise that if you ask the computer what the co-ordinates for the house in Pencil-vania st. are, it will tell them who is looking it up?

[@farstrider79]

Yeah, as long as you're not an idiot, that's completely fine.

[@davehumpleby3440]

I've been subscribed to your channel for a while now, but expect an influx of viewers from Paul Messner's channel. If you watch his latest post, you'll understand. 😂

[@worstuserever]

Same here, both great channels. I just commented on Paul's suggesting a collab. I think they'd get on like a tarp on fire. 😁

[@arthurvandelay411]

G’day from Australia. I’ve relatively recently found your channel and loving it. I’m wondering what you know about the flipping of the magnetic poles, the chance of it happening any time soon, and what effect it will have, both to navigation in the short term and also to life in general longer term.

[@TheMapReadingCompany]

Apparently the last time the magnetic poles “flipped” was 780,000 years ago. So I assume we’ll be OK for a while.

[@zembalu]

Can there be local abnormalities in the magnetic field? Of course, there are manmade ones, like power lines or bridges of steel, but I think of geologic formations and the like. If that is so, in which magnitude? I think, with a compass reading going wrong even by a degree would not really matter. But I use a monocular telescope (8x30) with built in compass and streak plate. Mainly for better eyesight, but the compass comes in handy for triangulation, which is a nice hobby :-).

[@TheMapReadingCompany]

Compass don't work on some sections of The Cuillins on the Isle of Skye in Scotland. I imagine this happens in many places with ferromagnetic rock.

[@lifeontherocks7441]

Great video. Is there a good phone app for telling you your declination?

[@TheMapReadingCompany]

I don't know but there must be - there seems to be an app for everything, but I just do land nav with a map and compass (that way the batteries never run out).

[@lifeontherocks7441]

@@TheMapReadingCompany i just mean to check the declination In the area before u set off? Which website did you use?

[@barneykennett9282]

Nice...👍.

[@billy4072]

So. ..Check your declination, before your peregrination. 🤔🙄💪

[@stuartadair7052]

Does that website give you declination or GMA?

[@JackAlford]

Legend mate, thanks for this. Great video again 👏🏼

[@IrelandOutdoors]

Hi Wayne, great video, but would you be able to do one on measuring the actual declination out in the field and not estimating. Think that would be a good one!

[@TheMapReadingCompany]

Hi I’ve already done that video using your compass to work out the actual declination in any area. - just waiting for time to edit it. The video I just posted (calculate declination) was just answering a question posted in the comments box about how to do this from the info on a map.

[@89lx98]

Thanks for the great videos!

[@mrparlanejxtra]

I have just had a brilliant idea. If you take your compass neck string and a spirit based marker pen you can colour in every second centremetre to make a measuring tape so you can lay that on your track on the map to measure out the distance you are going to travel.

[@TheMapReadingCompany]

silvasweden.uk/collections/navigation-accessories/products/distance-lanyard

[@muhdamsyar4800]

Thaank you

[@rashie]

👍👍

[@mihailvormittag6211]

👍

[@soldier-Dave]

👍thank you!