GPS Tracklog

A gps tracklog is a collection of track points along the course of a route. It’s essentially a bread crumb trail of the path of the route to be navigated. Tracklogs can tell us where we have been and therefore how to get back to where we started. More importantly, if prepared in advance, a tracklog can tell us where we need to go.

Tracklogs are most often created by a GPS instrument as the user navigates a desired route or path. It’s a recording of the path navigated. Not all GPS instruments utilize tracklogs. Some instruments only give the user an active tracklog with no ability to save the tracklog as an individual file.

The various GPS instruments handle tracklogs in different ways. Even within a manufacturers product line, the tracklog functions are different mainly due to product evolution. Some instruments only allow the user to work with an Active or Main tracklog. Other units allow the user to save tracklogs.

The Garmin GPS III+ and earlier units do not allow tracks to be uploaded to saved logs, so all uploaded tracks go to the main or active tracklog. It’s important to remember to save each individual tracklog from the Active log if you intend to have multiple tracklog files available on the instrument.

There are limits on how many track points can exist in a tracklog file. Many units allow more track points in the active log than the saved log. When a tracklog is saved the number of track points (resolution) is reduced to a number less than or equal to the maximum number of units allowed for a saved log. Early Garmin units allowed 250 track points in a saved log. Some of the higher end units like the Garmin 176C allow for 500 track points in a saved log file.

On the later Garmin units, you can load tracklogs directly into saved logs in the gps instrument. These files must not be over the maximum number of track points otherwise the file will be truncated. It’s a good idea to have tracklogs stored on your computer in a reduced format (less than or equal to the maximum number of track points allowed in a stored tracklog for the intended instrument).

Also, you must keep in mind that any track uploaded which does not have the name ACTIVE LOG will be sent to a 'saved track' log on the Garmin units capable of uploading to stored log files.

Above is a Garmin MapSource screen shot of the Black Bear Pass trail tracklog in Southwestern Colorado. It shows the actual path of the trail from US Hwy 550 west to the Pandora Mine on the eastern edge of Telluride Colorado. (Note the switchbacks southeast of the Pandora Mine).

Above is a Delorme StreetAtlas screen shot of the same tracklog display.

Why waypoints aren’t good enough .....

Above is a screen shot from MapTech’s Terrain Navigator showing a section of the Floy Wash trail near Green River, Utah. Assume we are traveling in a west-to-east direction. At the waypoint FWWE11,which direction should we go?

(Note that in the real world, the difference of the two paths is not that apparent, in other words, the 4WD route doesn’t look much different than the more improved road you have been traveling on. Note also that there is a mountain to the east so you can’t see what happens to the trail much beyond the intersection.)

A decision has to be made. At the waypoint (intersection ‘Y’) the route directional line follows the direction of the 4WD trail. Would you take the 4WD trail at that intersection?

Above is a screen shot of the same trail including the tracklog. It’s obvious from the tracklog path which way we should go. That’s the importance and value of the tracklog. It removes uncertainty.

The first time we traveled this route, we did not have a tracklog of the route. We took the 4WD trail which led us up a canyon along a sand wash that became more and more technical the further east we traveled. The trail eventually lead to a dead end. All that was lost was a little time and a lot of energy fighting our dualsport bikes in the sand.

Hopefully this will convey the importance and added value that our tracklogs add to the G-Guides we offer. All G-Guides have complete tracklogs as well as waypoints.

Trek Now !