Latitude & Longtitude

[+The Pickerings]

I have been using my GPS on MGRS for years, however I recently went to do a cache and there was sum mathematics involved.

 

I had to add and then subtract some numbers from the lat and long.

 

When I do this is it a straight forward mathamtically process or is there a special way with lat and long?

[jholly]

I have been using my GPS on MGRS for years, however I recently went to do a cache and there was sum mathematics involved.

 

I had to add and then subtract some numbers from the lat and long.

 

When I do this is it a straight forward mathamtically process or is there a special way with lat and long?

 

It is a straight forward process. However, it depends on what the format is. If it is DMS, then remember there 60 seconds in a minute and 60 minutes in a degree. Make sure you carry and borrow correctly. If it is DM.mmm, then you have to borrow and carry correctly, Likewise with DD.ddd. If it is UTM your on your own.

 

Jim

[WPMD]

My (cheap) GPSR has a calculator on it. I'm sure most have this feature.

[+victorymike]

If it is UTM your on your own.

Jim

 

UTMs are the easiest as long as you are in the same zone (which more than likely you will be). The zone is the first number (something like 14T for me), followed by the Latitude and longitude. The Latitude and Longitude in UTMs are broken up into meter square grids. If the Latitude number goes up by 1 then it is one meter more. If the Longitude goes up by 1 it is 1 meter more. Nice easy square grid...and easy addition, subtraction, division, etc. Sometimes it is easier to convert a coordinate to UTMs to do the math on it.

[+twolpert]

I have been using my GPS on MGRS for years, however I recently went to do a cache and there was sum mathematics involved.

 

I had to add and then subtract some numbers from the lat and long.

 

When I do this is it a straight forward mathamtically process or is there a special way with lat and long?

 

It is a straight forward process. However, it depends on what the format is. If it is DMS, then remember there 60 seconds in a minute and 60 minutes in a degree. Make sure you carry and borrow correctly. If it is DM.mmm, then you have to borrow and carry correctly, Likewise with DD.ddd. If it is UTM your on your own.

 

Jim

UTM is easiest of all. The easting and northing are in meters. Just remember that the easting increases as you move east and the northing increases as you move north. As long as you don't cross a zone boundary (and what cache owner would be that cruel ), addition and subtraction is trivial.