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GPS position discrepency - Printable Version

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GPS position discrepency - scoffer - 07-12-17 05:14 PM

I had taken a picture of my plotter over the weekend to show some buddys a massive school of perch I had marked. I wanted to plot the GPS position on Google maps so I could show them where it was relating to land locations. When I did the DMS to Decimal Degrees conversion so Google Maps would plot the coordinates, it ended up putting my position on land. However, on the chart plotter, the boat position displays correctly on the map. See the attached images.

Is Google Maps off or something? Is there a setting that I need change somewhere on my a78 so that it shows a corrected coordinate? I just want my position info to be as accurate as possible in the event that I ever need my coordinates for rescue or towing purposes.


RE: GPS position discrepency - Chuck - Raymarine - Moderator - 07-19-17 11:18 AM

Welcome to the Raymarine Forum scoffer,

While I strongly suspect that there may have been an issue in the conversion, no screen snapshots from the MFD have been attached to your thread to permit further investigation of this issue. That said, please click here to view a FAQ addressing this subject.


RE: GPS position discrepency - scoffer - 07-21-17 01:32 PM

[Image: attachment.php?aid=1180]

[Image: attachment.php?aid=1182]

[Image: attachment.php?aid=1181]


RE: GPS position discrepency - Chuck - Raymarine - Moderator - 07-24-17 08:53 AM

Scoffer,

The symptoms which you have reported appear to be linked to an inconsistency in the units of the position coordinates which you are entering into the conversion utility shown within your screen snapshots. Raymarine products report position coordinates in DDD-MM.MMM (Degrees Minutes) format, not DD.DDD (Degrees) or DD-MM-SS.S (Degrees Minutes Seconds) format as you have attempted within the conversion.

Correctly converted to DDD.DDDDDD (Degrees) from DD-MM.MMM (Degrees Minutes), the following are the correctly converted values:

Lat. 41-42.700N correctly converts to 41.711667N (DDD.DDDDDD)
Lon. 086-57.166W correctly converts to 086.952767W (DDD.DDDDDD)


[Image: attachment.php?aid=1187]


RE: GPS position discrepency - scoffer - 07-24-17 10:45 AM

Thanks for the clarification Chuck. I was thinking the decimal value after the minutes symbol was Seconds. With the value correctly entered during the conversion, the correct location is shown on Google maps.

Might I suggest that the Minutes symbol be moved to the end of the entire Minutes value to prevent that confusion in the future?


RE: GPS position discrepency - Chuck - Raymarine - Moderator - 07-24-17 11:17 AM

Scoffer,

Q. Might I suggest that the Minutes symbol be moved to the end of the entire Minutes value to prevent that confusion in the future?
A. That's a very good suggestion and it will be logged accordingly. I have accordingly moved this thread to the Feature Suggestions category.