Which Co-ords? NGS or Geocaching.com Why different?

[mchsbr]

Which co-ords do you use to get closer to finding a benchmark? I've put both into my Mapsend software and sometimes they are really far apart. Also, why or how are they different?

[+Black Dog Trackers]

Difficult to say without a specific example of the two versions of coordinates from you.

 

The only possibility I can think of (and you probably realize this already) is a problem with the difference between coordinate formats. The geocaching PID sheets give coordinates in H DD MM.MMM (Hemisphere, Degrees, Minutes and decimal-minutes) while the NGS datasheets are in DD MM SS (degrees, minutes, seconds). The software you use (Mapsend or the software inside your GPS) must know, or be able to figure out from the way you enter it, which format of coordinates you are giving it.

[+raouljan]

make sure your datums match

 

>Personally Responsible for the Recovery of .00217% of the Benchmark Database!<--watch this number!

[mchsbr]

LZ0126 in Pennsylvania. When I put the co-ords from NGS and geocaching.com into my Mapsend program, they are about 1200' apart. They are both NAD83. Why are there two separate sets of coordinates for the same benchmark if they are using the same datum?

[+gnbrotz]

NGS lists using the degree, minute, second format and GC uses degree, minute.minute.

 

Datums are identical, and both sets of coords represent the same point on the earth.

 

Greg

N 39 54.705'

W 77 33.137'

[+Lil Devil]

The datasheet says:

NAD 83(1986)- 41 03 55. (N) 076 11 35. (W)

which is in DD MM SS (H) format.

 

Geocaching.com says:

N 41 3.917 W 76 11.583

which is in H DD MM.MMM format.

 

When you convert one format to the other, they are equal. For instance, take the 55 seconds, divide it by 60 (max seconds) and you get .917

Or take 35, divide it by 60, and you get .583

 

Somewhere in the MapSend options, you should be able to tell it what format you are supplying.

 

Lil Devil

[+Black Dog Trackers]

That's one thing I like about lostoutdoors.com (there I go again). It takes either DD MM.MMM or DD MM SS format and figures out by itself which you're giving it.

 

Other softwares and web pages probably do that too, but I don't know.