Uploading the same .gpx file to both BaseCamp and Garmin Connect gives me vastly different numbers for the elevation gain (948' vs 424'). Can anyone explain this anomaly? Is there a bug in one of these programs? The length of the track is close (7.2 miles vs 6.98 miles).
I’ll try to help you unravel what’s going on. Within the last year or so, Garmin has added summary data to tracks on some devices. If your device is one of them, then it is possible that BaseCamp is showing the summary data while Garmin connect is calculating the results from the stored track data.
The summary data mentioned above comes from the real-time changes in position and will almost always differ from the stored track due to each using a different number of data points. You can export a gpx file of your track from BaseCamp and view it with a text editor like notepad or wordpad. The summary data will be at the beginning of the track with distances in meters and time in seconds (thus speeds will be m/s).
As an alternative, in BaseCamp you can delete a single point to force a recalculation using the stored track data. Pick a point along a straight section of your track. You can undo it after you observe any changes.
The summary data mentioned above has also been plagued with an issue where it appears that sometimes a phantom point (not actually part of the track) is used which can cause excessive errors to the summary data. Garmin has been working on this issue, so if this is your problem, keep your eyes open for any firmware updates.
If this isn’t your problem, then I’m afraid I can’t be of much help.
