I have the Garmin GPSmap unit and the Garmn MapSource CD. I'm attempting to add some points from my handheld to my home computer. When I take the position reading from my handheld, and locate those longitude and latitude numbers on my computer, I'm several miles off. Hope I'm explaning this well enough. Can anyone tell me why? thanks
capedorysailor@coastalnet.com
Garmin GPSmap & MapSource Question
Moderator: Jim Walsh
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Catherine Monaghan
Re: Garmin GPSmap & MapSource Question
Scott,
Make sure the Chart Datum used by the MapSource CD is the same as that used on your paper charts and the GPS. Most US coastal charts use the WGS-84 datum, but not all. The datum is indicated on each chart. The GPS needs to be set to the same datum as the chart. Also check your GPS and see if you have it set up to display in statute miles or nautical miles. Check the software as well. Set them both to use nautical miles. If both the GPS and software are set to the same units of measure, one would hope that the numbers would be the same.
How are you entering the waypoints using the software? My GPS (Lowrance MT3000) uses MapCreate software and I can enter a waypoint by clicking on a buoy or reference point. If you're clicking on it, like I am, you won't be exactly at the charted lat-long found in your Light List. Using MapCreate I can Right-click on the waypoint I just entered and modify the lat-long as well as give it a name if I want. When I press Enter it updates and the waypoint will reposition itself. Sometime, the repositioning is not noticible since the waypoint is still right on top of the buoy.
By the way, I found a buoy out-of-position in the MapCreate software and I made note of it and placed an icon at the correct position (found it this past weekend). I also intend to notify the makers of MapCreate so that they can fix it in their software.
So don't fully trust the software. You can verify the position of a nav aid using a Light List.
Hope this helps.
Cathy
CD32 Realization, #3
Rahway, NJ
Raritan Bay
catherine_monaghanNOSPAM@merck.com
Make sure the Chart Datum used by the MapSource CD is the same as that used on your paper charts and the GPS. Most US coastal charts use the WGS-84 datum, but not all. The datum is indicated on each chart. The GPS needs to be set to the same datum as the chart. Also check your GPS and see if you have it set up to display in statute miles or nautical miles. Check the software as well. Set them both to use nautical miles. If both the GPS and software are set to the same units of measure, one would hope that the numbers would be the same.
How are you entering the waypoints using the software? My GPS (Lowrance MT3000) uses MapCreate software and I can enter a waypoint by clicking on a buoy or reference point. If you're clicking on it, like I am, you won't be exactly at the charted lat-long found in your Light List. Using MapCreate I can Right-click on the waypoint I just entered and modify the lat-long as well as give it a name if I want. When I press Enter it updates and the waypoint will reposition itself. Sometime, the repositioning is not noticible since the waypoint is still right on top of the buoy.
By the way, I found a buoy out-of-position in the MapCreate software and I made note of it and placed an icon at the correct position (found it this past weekend). I also intend to notify the makers of MapCreate so that they can fix it in their software.
So don't fully trust the software. You can verify the position of a nav aid using a Light List.
Hope this helps.
Cathy
CD32 Realization, #3
Rahway, NJ
Raritan Bay
catherine_monaghanNOSPAM@merck.com
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Bill Parker
Re: Garmin GPSmap & MapSource Question
ScottScott MacCready, New Bern,NC wrote: I have the Garmin GPSmap unit and the Garmn MapSource CD. I'm attempting to add some points from my handheld to my home computer. When I take the position reading from my handheld, and locate those longitude and latitude numbers on my computer, I'm several miles off. Hope I'm explaning this well enough. Can anyone tell me why? thanks
Check your MapSource settings, the progam is initially set to DD.MM.SS
whereas you most likely have the Gps set to DD.MM.mm
Bill
Bill
willing@gibralter.net
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Catherine Monaghan
Re: Garmin GPSmap & MapSource Question
Scott,
What Bill said, plus check the clock on the GPS (date and time). If they are incorrect, you'll also get bogus readings.
Cathy
catherine_monaghanNOSPAM@merck.com
What Bill said, plus check the clock on the GPS (date and time). If they are incorrect, you'll also get bogus readings.
Cathy
catherine_monaghanNOSPAM@merck.com