Google and DeLorme coordinates don't match GPS location
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17 years
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I have a Garmin 765T. I planned a trip by entering coordinates I obtained from both DeLorme Street Atlas and Google Earth (by placing my cursor over the desired spot and copying the coordinates given).
When I navigated to these coordinates, I found that I was 300 to 1500 meters off.
Also, I used the GPS “go to” feature and was not told I was “off course” when I was a street off but driving parallel to the route. I’m on my 7th Garmin starting with the GPS II and a laptop and never experienced this level of inaccuracy.
My son-in-law tried to tell me that GPS capability by entering coordinates is only accurate within 150 meters and any more accuracy is reserved for the military. I know that is wrong or none of the roads would match. Maybe Google Earth is iffy?
Any ideas why this model GPS is off so much or is it my method of getting accurate coordinates?
I will be using my “where am I” feature to record coordinates and test them against Google and DeLorme this weekend.
On a side note, is there any way to retrieve the coordinates from a “Favorite” in the GPS? I’ve marked several locations and would like to transfer them to my DeLorme maps.
Thanks!
Don S.
Dallas, TX
It probably has to do with the database
There are two major databases used for coordinate references. There is NAD 83 and WGS 84. NAD is the US National Datum which was created in 1982 and has been updated almost every year. It is scheduled to be replaced in the next couple of years with a new standard. The other is the World Geolocation Standard released in 1984. It also is updated almost every year and is based on measurements taken from space.
I have to work with both and I have seen differences between the physical location of the exact same coordinates depending on the database.
ɐ‾nsǝɹ Just one click away from the end of the Internet
Coordinates of Favorites?
On my 260W I enter Simulator mode press Where to>>Favorites>> scroll to the one I want and choose it. Then press Map>>Set Loc>> Then back to Tools>> Where am I>>. Coordinates are displayed with other info.
:260W, 50LM
Coordinates of Favorites
Thanks! I didn't know how to go directly to the favorite in simulation mode. That'll do it.
Could be this
When I navigated to these coordinates, I found that I was 300 to 1500 meters off.
Any ideas why this model GPS is off so much or is it my method of getting accurate coordinates?
See:
http://www.poi-factory.com/node/22935
Nuvi 660 -- and not upgrading it or maps until Garmin fixes long-standing bugs/problems, and get maps to where they are much more current, AND corrected on a more timely basis when advised of mistakes.
This site displays coordinates in decimal format
I had the same issue when trying to enter coordinates from Google Maps and found this site - http://itouchmap.com/latlong.html - which tells me the coordinates in decimal notation.
Note that the Garmin only supports up to 5 numbers after the .
Hope this helps.
This Site Displays Coordinates in Decimal Format
Wow, thanks. I noticed the restriction to 5 decimal places. This site is great & puts the coordinates where you can see them.
DonSwin
donswin wrote: On a side
On a side note, is there any way to retrieve the coordinates from a “Favorite” in the GPS? I’ve marked several locations and would like to transfer them to my DeLorme maps.
If you have a copy of MapSource, you can upload your Favoites to it and the list on the left side of the screen will include all the coordinates.
MapSource has some import/export functions, but I don't know if it would be possible to export to DeLorme that way. Might be worth a look or maybe someone else knows for sure.
"There's no substitute for local knowledge" nüvi 750, nüvi 3597
Google Earth coordinates
I've noticed that when looking at locations on GE that in many cases the route the camera car has taken doesn't exactly match the roadway as displayed by the satellite image. I'm looking at one now that has a 15 meter discrepancy. When I've used the coordinates of the street level camera and compared it to other sources, it seems to be better than if I took the coordinates off the roadway. In other areas, the camera and the roadway match very closely. When they're off, they all seem to be off in the same direction, as if the photo was skewed when it was pasted into the overall image.
"There's no substitute for local knowledge" nüvi 750, nüvi 3597
donswin wrote: When I
When I navigated to these coordinates, I found that I was 300 to 1500 meters off.
In my early attempts to build a POI file, I was manually copying coordinates to an Excel file and found that I sometimes transposed a couple of digits and was way off target.
Since then, I've been using Extra_POI_Editor ( http://www.poi-factory.com/node/21156 ) with Google Earth to build POI files. Using the Map Pin on GE and then doing a Copy and Paste it was easy to input the coordiantes to the program and it eliminated the human error on my part. Once the coordinates are entered, it displays the point on a map in the adjacent pane. This program really makes all this easy. Many thanks to turboccc for writing this program for us.
300 to 1500 meters seems to be a big difference. How are you getting the coordinates from the map program to the nuvi?
"There's no substitute for local knowledge" nüvi 750, nüvi 3597