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Last year I thought I would be "helpful" and I put LAT/LON in what is known as (DD) Degrees Decimal as well as (DMS) Degrees Minutes Seconds in documentation for High Desert Trails. Some of our route notes had (DDM) which is even more confusing - leftover from a previous capture of locations.
This is BAD for volunteers in the field.
Not only was the data confusing, it was hard for people to figure out what to type into their GPS units.
+42.36005 -71.056 -vs- 42° 21.603' N 71° 3.36' W -vs- 42°21'36.18"N 71°3'21.60"W
I'll particularly call out DDM which I think lends to A LOT of confusion: This format is sometimes referred to as just “GPS” and the data after the decimal is confused with decimal seconds, leading to errors in navigation. 3 input fields - to which people type in Degrees, Minutes, Seconds and end up in a very wrong location. When they really needed to type in Degrees, Minutes, and everything after the decimal point.
So - This year we came up with a GPS coordinate system standard:
http://highdeserttrails.com/downloads/HDT GPS Coordinate Standard.pdf
The idea is that any and all GPS coordinates that we publish will only be in (DMS) Degrees Minutes Seconds!
If you need them in any other format, you can derive in the field with division by 60.
We know that you can multiply by 60 to get DD back to DMS, but the majority of GPS units accept DMS.
The other thing is making people AWARE of these 3 systems of representing LAT/LON data.
Check it out!
- Kris
This is BAD for volunteers in the field.
Not only was the data confusing, it was hard for people to figure out what to type into their GPS units.
+42.36005 -71.056 -vs- 42° 21.603' N 71° 3.36' W -vs- 42°21'36.18"N 71°3'21.60"W
I'll particularly call out DDM which I think lends to A LOT of confusion: This format is sometimes referred to as just “GPS” and the data after the decimal is confused with decimal seconds, leading to errors in navigation. 3 input fields - to which people type in Degrees, Minutes, Seconds and end up in a very wrong location. When they really needed to type in Degrees, Minutes, and everything after the decimal point.
So - This year we came up with a GPS coordinate system standard:
http://highdeserttrails.com/downloads/HDT GPS Coordinate Standard.pdf
The idea is that any and all GPS coordinates that we publish will only be in (DMS) Degrees Minutes Seconds!
If you need them in any other format, you can derive in the field with division by 60.
We know that you can multiply by 60 to get DD back to DMS, but the majority of GPS units accept DMS.
The other thing is making people AWARE of these 3 systems of representing LAT/LON data.
Check it out!
- Kris