Posted by jim on September 02, 2002 at 06:48:34:
This was posted on a soutTexas fishing board but felt it might be advice for most of us. captJack is the answer man.
Posted by CaptJack on 15:47:56 8/30/2002 from 207.218.236.51:
In reply to: Re: where did you get that map ? posted by livetofish on 15:22:26 8/30/2002 from 66.139.225.97:
When you buy a regular 7.5' topo map the scale is 1:24,000 = 1"=2000'
The new regional maps are 1:100,000.
National Geographic maps are not in any set scale. They change the scale for the area that they cover and the size of the finished map. (they are unique- I always wanted to work there).
The most important rule to remember about the scale of any map is: If the map shows latitude and longitude-
1'(minute) of Latitude = to 1-NauticalMile =6076' (1- statute mile = 5280')
There are 60'(min) of latitude in a degree. 60"(seconds) in a minute.
note: Latitudes are the lines that run around the earth that are parallel with the equator. They are always the same distance apart. Longitude lines run north to south between the two poles and get closer to each other as they get closer to the poles. This is why we can't use them for scale.
All of this is why I keep telling everyone to take a good mechanical pencil and draw in the 1' latitude and longitude lines on their TopSpot maps. It makes judging/measuring distance and estimating GPS coordinates VERY EASY!!!!!
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