Main Menu
Newest Members
Erbeman, at61, Yeagerbombs, Clark225, neal shaffer jr
102327 Registered Users
Top Posters
TexDawg 82177
hopalong 73426
Pilothawk 72822
JDavis7873® 67375
FattyMcButterpants 60428
John175 ® 59617
Tritonman 56538
Derek 56121
SkeeterRonnie 52395
LoneStarSon® 51981
Forum Stats
102327 Members
60 Forums
853378 Topics
11192003 Posts

Max Online: 36273 @ 01/23/13 02:34 PM
Topic Options
#11800830 - 08/28/16 06:31 AM Gps coordinates and navionics
Bugzout10 Online   content
TFF Team Angler

Registered: 06/23/13
Posts: 3362
Loc: Weatherford Tx
Trying to load some coordinates on the graph and noticed they're off a considerable amount has anyone else had this problem? I've converted the coordinates in the correct form checked them on google maps and they're correct it's only when I use navionics that they're off

#11800843 - 08/28/16 07:08 AM Re: Gps coordinates and navionics [Re: Bugzout10]
Bandit 53 Offline

Registered: 04/22/11
Posts: 22
You have to choose the proper format in your unit for your waypoints. Most folk use degrees, decimal min or deg min sec.

#11800929 - 08/28/16 08:30 AM Re: Gps coordinates and navionics [Re: Bugzout10]
collincountytx Online   content
TFF Celebrity

Registered: 04/08/08
Posts: 9755
Loc: Dallas, TX
Double check the original waypoint unit format.

For example:
The Martin's Maps use NAD27 format
Most digital chart plotters use WGS84

The units look identical degrees, minutes, seconds. However, the NAD27 units are calculated by using triangulation from Meades Ranch, Kansas. The WGS84 units are calculated on an ellipsoid grid of the earth from space. Thus, the NAD27 locations can be off by as much as 200 meters compared to WGS84

There are lots of online coordinate conversion calculators

Here's a good link for you

Map Datums

online calculator link
online GPS converter


© 1998-2016 OUTDOOR SITES NETWORK all rights reserved USA and Worldwide