Magnetic Declination and Topo Maps

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Just a quick link, I ve noticed in quiet a few posts that quiet a members are using topo maps and compasses which is excellent. Remember when using the same before using or transferring one to the other you need to take into account magnetic declination. The site below is quick and accurate.

http://magnetic-declination.com
 
The golden rule of map reading:
Is it lat or lon or lon or lat first....?
A very simple method is.
WALK ALONG THE PATH........THEN CLIMB UP THE HILL.

Here is a very good read on how to read a map plot your course, use a GPS.
it is very informative and very easy to get your head around.

go to this site it is a new section for Hunters in State Forests

www.dpi.nsw.gov.au/hunting

then go to,
new training modules for public land hunting
then go to
Additional training for public land hunting

scroll down page to,

Outdoor Navigation

you will be quite impressed as someone has done there homework on this article.
it is not heavy reading.
 
1st rule of map reading -

Read and understand the Map Legend, it's info, and symbols.

Geographical Co ordinates are always stated as Latitude then Longitude ie what your GPS uses. ie up/down then left/right

Latitude (parallel to the equator) the horizontal lines are degrees North or South starting at 0deg on the Equator to 90 degrees at each Pole, expressed as a positive figure north of the equator ie 40 N and as a negative figure south of the equator ie -38 S.

Longitude (the "vertical" lines pole to pole) the vertical lines start at 0deg intersecting Greenwich (London, England) and finish at 180 deg (the imaginary line in mid Pacific), expressed as a positive figure in an easterly direction ie 135 E and as a negative figure in a westerly direction ie -120 W.

However -

Grid Co ordinates are expressed as an easting, then the northing. ie left then up

The map grid (squares) has a number just outside the map boundary (horizontal and vertical), also the Legend will give the Grid Zone (needed to ID the map you are using) ie 55J. So you pick a vertical line number to the left of where you are (in this part of the world) ie 06, then estimate in 1/10ths where you are or want to go between it and the next grid number (lets say half way =5) then the number of the grid to the south ie 65 and then the 1/10 position (lets say 3/10 =3. The grid reference is then expressed as 55J065653.

My point being that Lat/Long (in Australia) is expressed as down then left and Grid reference values are expressed as left then down and should not be confused with each other.
 
Thanks Condor22 now you have totally confused the hell out of the general poulation.
it is not that hard.......sorry.
If I was to give that writing to a layman to understand I would say he would tear it up and buy a GPS.
CHEERS
 
wow, I think we should, or the idea was just about reading and using topi maps. Using Lat/Long is rare in Australia, and especially at the recreational end.

You just have to remember that a grid reference is either 4, 6, 8 or a 10 figure ref. Divide the reference into two groups at the centre. This gives you the two easting and northing references. So a grid ref of 45671234, is divided 4567 and 1234.

Remember that applying the reference to a map, is like dating a woman, you have to come across before you go up, so the first group of digits are easting which are across the bottom of the map, the first two digits of the group represent the easting line ie. 45 then you locate the northing by locating the first two digits of the second group ie. 12. You now have a grid square.

The next you take the third digit of each group and divide the grid square into 10, this digit represents the distance of division with in the grid square, You do this to both 3rd digits.

The fourth digit is repeating step two(as with the third digit) but the subdivision is of the square represented by 6 & 3

It would be rare for most people to use 8 or 10 figure grid references, these take skill to be able to tabulate, I would work on 6 figure only. Attached is a Map protractor available from most map shops for a couple of bucks, essential if your using paper maps. Well worth the investment and you will note that on the inside they provide you with a scale tool for different scale maps to be able to plot the 3rd reference.

simple, would be even simpler if I scanned it the right way up, use your imagination

1392186357_protractor.jpg
 
Yes well presented Villiage.
Available from most map shops.
As I stated very simple if you understand.
The only time you may need latitude...longitude cordinates is if you are giving directions to emergency services for a rescue helicopter retrieval. As there system is based on global positioning not map grid reference. They do not operate from area maps but degrees, minutes, seconds.
This is where you GPS unit shines.
Cheers
 
You wrote The golden rule of map reading:
Is it lat or lon or lon or lat first....?
A very simple method is.
WALK ALONG THE PATH........THEN CLIMB UP THE HILL.

Excuse me, but you were wrong, you state lat long etc then use the analogy "WALK ALONG THE PATH........THEN CLIMB UP THE HILL." which is referencing to Grid coords not Geographical.

What I wrote was to explain the difference and if confused a reader needs to learn more than they know.
 
not that well presented the smithy, think I started to confuse myself, it's easy when you know what your doing, but I find it bloody hard to explain it.
 
condor22 said:
You wrote The golden rule of map reading:
Is it lat or lon or lon or lat first....?
A very simple method is.
WALK ALONG THE PATH........THEN CLIMB UP THE HILL.

Excuse me, but you were wrong, you state lat long etc then use the analogy "WALK ALONG THE PATH........THEN CLIMB UP THE HILL." which is referencing to Grid coords not Geographical.

What I wrote was to explain the difference and if confused a reader needs to learn more than they know.

Sunshine that was just a figure of speech it was not a direction or a quote. Just is it this or is it that.
I could have said is it eastings or northings or vice versa.
and then made a quote.
its all about helping not nit picking.

Nobody in the business of prospecting or fossicking uses latitude longitude to navigate unless it is in the marine enviroment or aircraft industry or Emergency services.
I am in the emergency services so I use both.
on a regular basis.
 
I spent 30 yrs with the military, my brother 20yrs with the Survey Corp as a cartographer. Perhaps I'm no expert. but...

My advice to anyone intentionally going into a remote area is, if what I said confuses, then you don't know enough about maps to bet your life on it.

I'll say no more
 
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