Garmin Report No.sPSC8465 (Parent) & PSC 6284 First Reported November 2017 (RE: CASE ID - 1391515 << Reference ID: 10377900K0 >> <Q#:1000104>) and since (at least GC v 3.22.5)
I have the following issue with GC (desktop). If I carry out an activity and record it with my Edge 1000, I get what I believe to be an accurate elevation gain and loss. Those elevations are verified (within reason) by those on the same ride who also use Edge devices and those using STRAVA from smart phones. This problem shows itself in two distinct ways.
a) If you carry out an activity (for me this is on Edge 1000) and then save that activity as a course the elevation reported for the activity is carried over at the same value as the activity showed (as you would expect).
However! If you edit the saved course in Garmin Connect (even by moving a pint only a few metres) then the totals for elevation loss and elevation gain, becomesignificantly reduced!
b) If you CREATE a course from scratch in Garmin Connect and send it to your device, the reported elevation calculated during course creation is carried over to the device (Edge 1000 for me) & detailed in the 'Summary Page' for the course on the device as you would expect).
However! My Garmin device (in common with other Garmin devices & SmartPhone Strava Apps) will report a much greater total for elevation loss and elevation gain.
Early on in there was a reported 'Fix' from Garmin - as previously, when a course was sent to your device, the device 'corrected' the elevation totals in the course 'Summary' page to those that you would eventually confirm AFTER completing the course.
An example would be a course CREATED in GC showed a total expected elevation of 814 feet. The elevation change given after actually riding the course was1481 feet! A difference of 667 feet! Another example, my ride today had a total elevation gain of 2,244 feet and a loss of 2,238 feet over a distance of 47 miles. After saving that as a course and moving the end point of the course by only a few feet, the reported values in Garmin Connect change to 1,532 and 1,533 feet!
I have corroborated the total elevations displayed on my device, with that recorded by other riders of the same course on many occasions - I BELIEVE MY GARMIN 1000 ;-)
Our large cycle club has a Garmin Connect User Group, where all of our previous and planned courses are shared with members. Any courses created since this problem developed no give users a completely unrealistic sense of the likely intensity of the ride based on Elevation. I ride most of the courses myself first but if I later need to edit them in any way, the original (as ridden) elevation detail then becomes severely reduced as in a) above. If I create a course from scratch (without riding it first) then again, the elevation reported will be much lower than that eventually experienced during the activity. Any courses saved and un-edited before this error started retain their original and correct elevation data (unless I edit and save them!). This has resulted in our club sadly (and hopefully only temporarily) moving to another platform for course design & sharing. I still create the same courses in GC in the hope that one day they will be able to show the correct elevation data. I really hope this gets sorted soon, so that we can go back to using GC to share our Club Rides!
Garmin tell me that only 1 or 2 other people have reported this same problem and that it is being investigated in America.
PLEASE if any users can replicate these problems pleas let me know. Also if you experience the same issues, can you report it to Garmin, perhaps asking them to associate it with PSC8465 (Parent) or PSC 6284. I can easily provide example courses and activities for comparison, but I'd really like people to replicate this for themselves to prove my findings :-)
I am seeing the same thing. If I plot a course using plotaroute.com I receive an amazingly accurate elevation track vs. the actual hike. It was off by a whopping 1 foot with a 30ft offset due to a 30ft off calibration over the source of 2.6mi. The course was otherwise precise enough to make me wonder at faked data. I export the route as a .tcw file from plotaroute and import into connect (web application) and the elevation track is way off. The route appears correct, but the returned elevation data is poor. Almost as it is shifted in the X,Y somewhere, resulting in a bad Z.
I was hoping for a bit better GPS tracking (I swear my VA3 was better), but pleased with the elevation tracking matching the plotaroute.com map. Not too impressed with the GC maps.
