GPS Coordinates

[shackman]

I'm new with using a GPS, but I am getting things figured out. I have some really nice 3D lake maps from Mapping Specialists for some Wisconsin lakes. They show the GPS coordinates on the edges of the map. However, they only show 2 digits for the 'seconds' reading. Does anyone have experience with these maps? When they show 30 seconds, for example, do I program my GPS as '030', or '300'? Does this make a big difference? Been trying to find some waypoints that I have entered into the GPS using this map, but I'm not confident in my findings on the water.

[REW]

You can do it several different ways.

You need to first set up your GPS to the measuring system that you want to use. If you happen to have a mapping GPS, you should use the default settings that are set up for the maps to be loaded.

If you have a non mapping unit; you can use the system that you are comfortable with.

i.e. you can use degrees, and 10th and 100th thereof. i.e.
94.325 degrees.

Or you can use the degree, minute, second system.

i.e. 94 degrees, 13 minutes, 12 seconds.

It is your choice.

If you don't understand the difference; go to a library, and get a book on Navigation. This book will explain the relationships of these units, and what they mean as far as navigating on the face of the planet.

Take care
REW

[Cooker]

The coordinate entry can make a big differnce in the accuracy of your waypoint. The thing to remember is that there are 60 seconds in a minute and 60 minutes in a degree. If you see a coordnate listed as 93.325 degrees and want to convert to degrees/minutes/seconds, you simply remove the number to the left of the decimal and multiply by 60. For the example above we multiply .325 by 60 and get 19.5 then we remove the 19 and multiply .5 by 60 ( = 30). We end up with 93 degrees, 19 minutes and 30 seconds. To go the other way we divide seconds by 60 and add to the minutes, divide this number by 60 and add to the degrees. Also, recall that as a rough rule of thumb in the midwest, every degree in Latitude equals 60 miles (this stays constant with increasing and decreasing Lat) and each degree in Longitude equals 49 miles (this reduces the farther north you go). Given this each second in latitude entry error can result in 88ft of error when trying to locate the spot.

[shackman]

Thanks, REW and Cooker. I think I have it figured out.

First, I believe that the 3rd number that my GPS is looking for in the 'seconds' catagory is the tenths of a second as there is a decimal point present. If I don't have that close or detailed information, I will just put a 0 after the decimal and use the whole number.

Now, looking at a Hotspots map of Leech Lake, they show the coordinates differently. They show the degrees, and then the minutes, including 'tenths' of a minute. So, for example, if they show the minutes as 10.334', I would multiply the .334 x 60, giving me 20.04 seconds. Rounded, I would enter just the 20 seconds into the GPS. Is this correct????

Again, thanks for helping to teach this old dog some new tricks. Good fishing to you....

Shackman

[Cooker]

You are correct.