Using A Back Bearing To Locate Your Position on Your Map

Тәжірибелік нұсқаулар және стиль

Using a back bearing to locate yourself on your map - Podcast created for Higher Skills module JXH-3030 at University of Wales, Bangor.

Пікірлер: 45

  • @mikeneale2459
    @mikeneale24595 ай бұрын

    EXCELLENT! THANK YOU!

  • @Isoundlikefmradio
    @Isoundlikefmradio12 жыл бұрын

    Jack this a fantastic video - I've always struggled to get this element of navigaiton but you explain it really well!

  • @thelowbass2812
    @thelowbass28127 жыл бұрын

    i would recommend to take 2 back bearings to get a better knowing of your location

  • @biggles1024
    @biggles102412 жыл бұрын

    Very well put together and presented video. Thanks for posting it. :)

  • @aultguish1
    @aultguish112 жыл бұрын

    Absolutely nothing wrong with what the guy done, brilliant wee vid. Another way of remembering whether to subtract or add.......Mag to Grid, get rid. Grid to Mag, add. In other words, real life bearing (Mag'netic) to map (grid'lines)....get rid.

  • @curtite
    @curtite7 жыл бұрын

    Very helpful, especially with magnetic declination in my area is 14 degrees west can mess us a compass reading to the map without subtracting. Thank you so much.

  • @mikeythechamp
    @mikeythechamp3 жыл бұрын

    Excellent Jack

  • @scottdeas834
    @scottdeas8347 жыл бұрын

    Thank you, very helpful.

  • @etrnlcoca
    @etrnlcoca11 жыл бұрын

    Well done. Thank you.

  • @kevinshere67
    @kevinshere6710 жыл бұрын

    Really helpful video.Thanks

  • @CatOfDamianx
    @CatOfDamianx11 жыл бұрын

    Thanks you explained it really well

  • @PaulWellner
    @PaulWellner10 жыл бұрын

    Nice job!

  • @martinjolly
    @martinjolly12 жыл бұрын

    Nice - Thank you

  • @dlloyd5048
    @dlloyd50482 жыл бұрын

    At last one I can follow

  • @charliewhisky111
    @charliewhisky11111 жыл бұрын

    nice explanation. thanks.

  • @IqbalHamid
    @IqbalHamid Жыл бұрын

    Further tip: The closer to you the landmark (from which you are taking the back bearing from), the more accurate will be your positioning.

  • @billperry7549
    @billperry75492 жыл бұрын

    It’s magnetic variation, difference between grid North and Magnetic North. MV!!

  • @encodecode1059
    @encodecode10599 жыл бұрын

    Great!

  • @joeycarnevale9219
    @joeycarnevale92198 жыл бұрын

    brilliant

  • @BORIONTV
    @BORIONTV13 жыл бұрын

    YAY JACK ! That was Sooooo helpful ! ! ! As a homage I'll always do it "JACKS WAY" %7™

  • @dwcubatch83
    @dwcubatch8313 жыл бұрын

    3 degrees west declination, you should "add" not subtract

  • @phildo864
    @phildo8648 жыл бұрын

    Great video. One of the very few to indicate that the orienting arrow has to point north on the map when lining up the median lines. Colin did get you on the fact that this isn't using a back bearing. 259 degrees would be your back bearing. To use resection using your back bearing you would just reverse the direction of travel arrow so that it points from the hill top to your baseline which is the river and line up your dial to 259 degrees and do everything else the same. aultguish1, be careful with your rhyme as it only works when you have a west declination. You do the opposite when you have an east declination. That could get you in some trouble :) sboxjunk, that's a popular mnemonic device "west is best, east is least", but that is when going from the map to the real world: true north from the map to magnetic north in real life. It is the opposite when going from real life (magnetic north) to the map (true north). He does it right in the video.

  • @phildo864

    @phildo864

    7 жыл бұрын

    You are thinking about what to do when converting a map bearing to real life. He is taking a real life bearing and converting it to the map. Make sense?

  • @phildo864

    @phildo864

    7 жыл бұрын

    So here is where the confusion lies. For west declination you add the amount when going from the map, to the real world. However, you do the opposite for west declination when going from the real world to the map.

  • @phildo864

    @phildo864

    7 жыл бұрын

    So if you have a west declination, you don't add both times or both ways. You add one way, and subtract the other way.

  • @phildo864

    @phildo864

    7 жыл бұрын

    So he took a bearing on an object and got a reading of 82 degrees. We know it is off by 3 degrees because of declination. He subtracted 3 degrees to plot a line of 79 degrees on his map. Now if it was reversed, lets say he looked at his map and saw an object at 79 degrees. He would then add 3 degrees and that would be the course he would walk to hit that target.

  • @phildo864

    @phildo864

    7 жыл бұрын

    It can be confusing. Let's start with a fresh example. Let's pretend you have a 5 degree west declination for your area. Anytime you take a Magnetic reading with your compass and transfer it to the grid, you are going to subtract 5 degrees. So if you point your compass at a mountain top and it reads 360 degrees, when you look at your map the mountain top would be at 355 degrees on your map. "Mag to Grid" means to always subtract when going from magnetic to grid if you have a west declination. However, you don't subtract when going from the grid to mag. You do the opposite. So anytime you go from mag to grid you subtract and anytime you go from grid to mag you add. All of this is true if you have a west declination.

  • @IqbalHamid
    @IqbalHamid Жыл бұрын

    Why should you need three landmarks? Two should be sufficient, surely?

  • @triciarobinson1724
    @triciarobinson172410 жыл бұрын

    plus it would be a lot more accurate with a SIGHTING COMPASS that has a mirror and sight marks to look through

  • @indianacademicstudies291
    @indianacademicstudies2918 жыл бұрын

    nice

  • @marinkljun2914
    @marinkljun291411 жыл бұрын

    6×Sin 25°=6ו42=2•25 miles

  • @WHNorthcote
    @WHNorthcote11 жыл бұрын

    So how do you find your magnetic variation when away from the internet and in the middle of Wales? Also, does the magnetic variation have that declination all over the UK as well?

  • @adriangriffiths2142

    @adriangriffiths2142

    6 жыл бұрын

    Magnetic variation depends on your location and is stated in the legend of the map for that particular area. The magnetic variation is different in other parts of the UK. Each OS map will state Grid North, True North, and Magnetic North and the difference in relation to each other at the centre of that particular map in the year the map was printed. The annual change will also be stated so the difference for subsequent years can then be calculated.

  • @petar-boshnakov

    @petar-boshnakov

    2 жыл бұрын

    you can also find the declination if you take a bearing from an exact location on the map (where you are) to a known location again on the map. Then compare the magnetic and map bearings and you can find it without internet! ;) damn you read that on internet and i found that on internet :D

  • @billperry7549

    @billperry7549

    2 жыл бұрын

    It’s printed on the map you Mong!

  • @john84753
    @john847539 жыл бұрын

    You're not taking "back bearings"

  • @wxpm
    @wxpm7 жыл бұрын

    Nice well explained video , but you are not using back bearings , you are simply taking magnetic bearings and converting them to grid bearings then using a technique called re-section to find your position on a map

  • @paganphil100

    @paganphil100

    4 жыл бұрын

    DENBIGHVIDS / WXPM: Same thing, just different names.

  • @triciarobinson1724
    @triciarobinson172410 жыл бұрын

    also each mark that looks like a degree is actually 2 degrees....so 3 degrees is a nice female singing trio approved by prince charles....sorry... 3 degrees is ACTUALLY 1 and a half "notches" on the compass

  • @billperry7549

    @billperry7549

    2 жыл бұрын

    Use Mils. Used it for 50 years in the British Army. Best in the world!

  • @adriangriffiths2142
    @adriangriffiths21426 жыл бұрын

    The top of the names do not indicate North. He aligned the orientation lines of the compass incorrectly.

  • @colb3590

    @colb3590

    5 жыл бұрын

    You're wrong , names on maps are written from left to right , or west to east , so the top of a name does point north

  • @komos1756
    @komos1756 Жыл бұрын

    Pp

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