[alligatorsnz]

i know the gps essentially estimates where it thinks you are going to be... but given it also knows the barometric pressure and gps altitude - ( gpsmap62s) can one assume that when the trip distance comes out of the trip computer at the end of the day that this has measured ever single actually varying terrain length rather than just the as the crow flies flat distance.

i note that when i look at the elevation chart in the track log it is always some where between 1 and 2 km's shorter then the total track log indicated on the trip computer?

thanks

[yogazoo]

Unless your tracklog interval is set to Time => 1 Second your tracklog will always be shorter than your Odometer. Anything less than 1 Second log intervals will effectively truncate the distance. Hope that helps.

You raise a good question about whether or not elevation changes are factored in to the estimated distance. It would be easy enough for the unit to do with a Garmin map containing a DEM. Barometer elevation readings are just too jumpy to be meaningfull over a long-term calculation.

[Grasscatcher]

yogazoo, on 04 May 2012 - 10:01 PM, said:

Unless your tracklog interval is set to Time => 1 Second your tracklog will always be shorter than your Odometer. Anything less than 1 Second log intervals will effectively truncate the distance. Hope that helps.

Two questions....

1. What happens to all the distances associated with all the "random" points logged while stationary? Like during a lunch break on a hike?

2. How do you set a logging interval of "less than one second"?

[Walts Hunting]

Unless you are on a topo map it does crow flies.

You're comment that it estimates where it thinks you are going to be is incorrect it only tries to find out where it is at; there is no predictive factor.

Try loading your track to Connect.Garmin to get a good read of the file (or BaseCamp with topo does pretty good)

This post has been edited by Walts Hunting: 05 May 2012 - 02:16 PM