Track Logs
Track logs are lists of waypoints that were automatically recorded
either by a GPS or by a computer connected to a GPS such as can be
done using the Nobeltec program.They are a history of where a boat
has actually gone as compared to a route which is someone's choice of
where he'd like to go. I use them to get waypoints for building
routes. By that I mean that I display the tracklog waypoints as a
route in some program and then select those where I want to go. For
example you could import a track log as a route into CAPN, display
the route, change its color (to allow seeing the new route) and then
create a new route over the top of the track log waypoints.
For areas of the world that are well charted, this isn't too
useful, but for areas like the Western Caribbean where the charts are
poor you need to get waypoints from some where for reef passes etc.
Tracklogs are a good source.
FLorida to Honduras and back
The following files are tracklogs that I saved from my ICOM
GP-270ML gps from the trip I took from Florida to the Bay Islands of
Honduras thru Mexico, Belize and the Rio Dulce. The waypoint data is
in the format for my GPSDevComm program which can write the waypoints
to NMEA(for CAPN), Nobeltec and MaxSea formats. Each waypoint has the
date/time it was saved as its description.
See below to download a copy of the GPSDevComm program.
I have loaded these tracklogs into a Navigation program, took screen prints,
captured the images and posted them at
Tracklog Photos on the IslandPacket Photo site.
All of the following files are in this zip file.
The following two files are exports from the Nobeltec program of the
tracklogs of the boats: Miss Adventure and EOS:
Florida to Trinidad
The following files are the tracklogs for a trip from Florida to Trinidad. There are two gaps in the tracklog that occured when my GPS's internal battery went dead. The first is from Antiqua to Iles de Saintes and the second from St. Pierre, Martinique to Marin, Martinique.
All of the following files are in this zip file.
Fall 2005 to Summer 2006
We cruised in the same area as last season (Trinidad to Antiqua and back) only going to one new area: Antiqua and Barbuda. These were very nice. The anchorages on northern Antigua and southern Barbuda were hardly occupied and had very nice snorkeling.
Here is the tracklog for Antiqua and Barbuda. My GPS was having problems, and I lost the data for some of the legs. For example from Great Bird Island back to Jolly Harbor.
Antigua and Barbuda
The GPSDevComm program is downloadable from a zip
file. See the Readme.txt file inside the zip for
installation instructions.
Accuracy of waypoints
The Track log accuracy for waypoints on my ICOM GPS is controlled
by the Limit Max Track Error. This is defined such that "the
recorded track points connected with straight lines will always be
within the error tolerance of the actual track of the boat." It was
set to 0.05 nm for most of the tracks. I occasionally set the limit
to a lower value for some passes when I thought of it. A setting
of 0.01 saved a lot of waypoints.
Last modified: 19 July 2006