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Different Lat and Long

 
Sat, 03/29/2008 - 7:16pm

I just check and address in four different coordinates programs and got a different answer each time. Could drive you crazy. Used batchconverter,yahoo, google earth and geocoding. Which is the preference of the group?

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johnm405 660 & MSS&T
Sat, 03/29/2008 - 7:56pm

Coordinates

You are right about getting different readings.I was bothered by the same problem so I asked Garmin and here is the answer I received back.

Thank you for contacting Garmin International.

I'm happy to help you with this. I would use the google map as we get our mapping from the same company. Let me know if there is anything else I can do for you.

With Best Regards,

Nathan T

Product Support Specialist

2nd Shift Automotive Team

Garmin International

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Charlie. Nuvi 265 WT and Nuvi 2597 LMT. MapFactor Navigator - Offline Maps & GPS.
Sat, 03/29/2008 - 9:14pm

.

johnm405 wrote:

I just check and address in four different coordinates programs and got a different answer each time. Could drive you crazy. Used batchconverter,yahoo, google earth and geocoding. Which is the preference of the group?

My preference is the correct coordinates wink
Why there is such a discrepancy is anyone's guess.
Now I guess we can understand why Garmin and Navteq have errors.

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******************Garmin Nüvi 1300T****************Member 6523*******************
Sat, 03/29/2008 - 9:53pm

h ddd.ddddd

johnm405 wrote:

I just check and address in four different coordinates programs and got a different answer each time. Could drive you crazy. Used batchconverter,yahoo, google earth and geocoding.

Well POI Loader expects its input files (whether .csv or .gpx) to have coordinates specified in Decimal degrees i.e. h ddd.ddddd°. Google Earth .KML files are always written in that format too, so that's my preference.

Most software either uses this scheme by default, or can be set to use it.

Eg. MapSource:-
arrow "Edit|Preferences|Position" => Lat/Lon hddd.ddddd°

Google Earth:-
arrow "Tools|Options|3D View|Show Lat/Long" => decimal degrees

Nüvi 3xx:-
arrow "Where to?|Coordinates|Format"=>h ddd.ddddd°

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------------------------ Phil Hornby, Stockport, England ----------------------               http://GeePeeEx.com - Garmin POI Creation made easy           »      
Tue, 04/08/2008 - 5:41pm

Excellent reply

Excellent reply Phil!
Although my experience is brief, I've reached the same conclusion. Some coordinate programs only yield five decimal points and most require editing preferences. Google Earth provides six. Google Earth also allows me to pinpoint precise locations. Satellite view lets you pinpoint a house on a 400-acre farm address. grin

Not to say others won't do the same . . . just the results of my limited experience.

Sapwood

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Garmin Nuvi 260, IMac 2.4
Tue, 04/08/2008 - 6:06pm

maps are models

trying represent a three dimensional object which is not uniform. Different map projections have different pluses and misses.

Think about what a GPS is trying to do. It is triangulating a position based on 3 or more satelite fixes. But that location is relative to what? It is relative to a model of the earth. The models (maps) are tuned and calibrated - the most common is the WGS 84 datum (World Geodetic System of 1984).

This seems like a good url for an explanation of map projections and datums:

http://www.gpswaypoints.co.za/FAQ_map_datums.htm

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___________________ Garmin 2455, 855, Oregon 550t