Export to Strave: Wrong Elevation gain

Mike shared this problem 3 months ago
Not a Problem

Hello


after recording a track i have different options.

Locus shows me the correct elevation gain after saving.

When i export the track to a gpx file and upload this file to strava i get the correct elevation gain in strava

When i use the locus option to upload the track directly to strava i get a wrong elevation gain on strava. it don´t matter if i use the auto function after saving or when i upload it with the export function.

Comments (7)

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Hi Mike,

the first two methods prove that Locus export is OK. In the third case Strava calculates elevation gain itself - and that's the problem. I would contact Strava support for their opinion.

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it this the reason:


Device and elevation data For devices with a barometric altimeter the elevation data is taken as is from the file. Otherwise it is recomputed using the provided lat/lng points and an elevation database. More information.

Device type is detected in all file types from standard ‘creator’ tags. These tags are then matched to a list of known devices. In some cases the name of the device will be displayed along with the activity details on strava.com.

A generic “with barometer” device is provided to force the system to use the elevation data from TCX and GPX file types. One only needs to add “with barometer” to the end of the creator name. For example, a TCX file would include something like:

<Creator> <Name>My Awesome App with barometer</Name> </Creator>

and a GPX file should have an updated creator like:

<gpx version="1.1" creator="Best app ever with Barometer">

For total elevation gain, the value is read directly from FIT file headers if the device includes a barometric altimeter. Otherwise, elevation gain will be computed from the elevation data and may be different than reported on the device. Note that to compute elevation gain noise must be removed from the elevation data and different algorithms/sites will produce different results


https://strava.github.io/api/v3/uploads/

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Hi Mike,

when exporting directly to Strava, check "Preserve measured altitude" in the export dialog - this should prevent Strava from computing elevation from their elevation data.

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this option is activated but the problem is still the same

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Good day Mike,

I'm checking your problem and I'm unable to simulate it.

In case of enabled "Preserve measured altitude", elevation values on Strava page is real measured elevations and value itself is clickable ( see blue clickable "elevation" text on screenshot below?). Strava here offer option to replace measured values with values computed.

/RQTE0AAAAASUVORK5CYII=


In case of disabled mentioned option, result is as you may see below ... different and logically without option to replace elevation values ( they are already replaced ).

/vxvpEmTxtqKvyRAAhEg8P8BUDIvRRsPalAAAAAASUVORK5CYII=

So sorry, but I'm unable to simulate this problem. Anything I miss here?

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Today i recorded a track using the barometer

the shown elevationgain during the recording (1) isn´t exact. in my case it show most of the time 10% to much. Thats no problem for me. After saving everything is fine, it shows the correct value (2)

I´m using a Sony Z Compact. the more often i touch the phone the fault is getting bigger and bigger. No problem, it´s because how my phone is using the barometer. Today i made a lot of photos, so i get a real high fault


When i export the gpx and import the file to strava over the website i get (2) the same value locus shows after saving the track. I can´t correct this value on the strava website

When i use the direct export function i get the same value which locus is showing at the end of the recording but before the track is saved (1).

Here i can use the strava option for correction, but i get value (3) and not (2). because strava is using the gps high. So the barometerdata are gone when i´m using the option

When i use the gpx export and uplaof it to strava it shows me the real barometervalues.

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Hello Mike,

older topic I completely forget to react, sorry.

Just a quick explanation to you. Values in Locus Map:


  • value (1) are raw, almost unfiltered, measured statistics
  • value (2) are highly filtered values after some post-processing during saving

Value (1) are also exported to GPX or directly upload to Strava. Optimizations that are made on Strava side are not known to me and Locus Map has no effect on them. Only what may be modified here is "preserve elevation" checkbox, we talked about before.

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