SoSmellyAir

Using Golden Cheetah as suggested by Seattle Forrest, under Details, Device, the Device is just listed as "Wahoo fitness" and the Device Info field is blank.

spelger

there are a few tools that can be found here. one is a .fit file viewer with nothing to install.

spelger

i did some research a while back while writing my own app...

some interesting stuff regarding elevation and how strava handles it:
https://support.strava.com/hc/en-us/...-Your-Activity

and this if you need force barometric data for devices that don't support it or for those that do but strava has not caught up yet:
https://developers.strava.com/docs/uploads/

i consider this a bit of a hack since any elevation data can be uploaded this way. i think i only use this for one case and all others are just .fit files since they are smaller.

Racing Dan

Try riding a completely flat route along the coast and use the GPS to determine altitude. The resulting profile should be flat. If its not you have an indication how much GPS derived altitude data deviates.

Sy Reene

Does Strava with their elevation correction, as an example, rely on their presumed database of eg. hundreds/thousands of past rides along same routes where a barometric altimeter provided inputs -- and conceivably Strava could average those inputs for a theoretically more accurate correction?

Iride01 

I've wondered about this same thing too. Not just Strava, but RWGPS and all the others too.

Or is the amount of wacky data just too enormous? Even if you look at just relative info, how do you filter out stuff like errors for the constantly changing atmospheric pressure? While you could go out and get nearby weather reports now you are adding quite a bit of complication to the algorithms. I have gone for a ride and the barometer changed enough to have my starting elevation and ending elevation which are the same place be off by 400 ft and maybe quite a bit more.

So maybe they don't. If you know the complication to coding that would add and then multiply that by all the other things that would have to be looked at with their unique set of things to complicate the code, then with the other regular things like creating new features and new flashy looking user experiences (which we all dislike.... initially till we get use to them) the Strava and other sites programmers are trying just to keep up with, then it might be too much for them to worry about.

I've also wondered if they do this for estimated power too. There are some instances they come up with a really bogus high power for my efforts that I can't really come up with a explanation for. Especially since many are the same route and roughly the same time.

WhyFi

This was my understanding of how they came up with their elevation data, but I could be wrong.

spelger

if i recall from my past reading Strava uses their digital elevation map (DEM) as a base line and augments it with barometric elevation data from real rides. the DEM is only so accurate so relying solely on that is guaranteed to be incorrect/inaccurate as far as elevation/total climb goes. i'll bet this additional information is averaged to create something more accurate. and the coding in this respect is not complicated, only the data set grows so adds time to compute but there are optimizations that can be put into effect such as knowing ahead of time what the elevation profile is for a given stretch of road/trail, only the intermediate lat/long need be interpolated from two nearby known locations.

Seattle Forrest

If I was Strava, I wouldn't update my DEM from incoming ride data because the quality of the elevation numbers is so variable. Also because it would allow people to troll you kind of like how they used to "digital dope" but just send rides with deliberately bad data to break a segment or something.

spelger

I agree that the data is variable for a...variable number of reasons. But likely better than the raw satellite derived DEM.

here is where I read about how strava improves their DEM:

https://support.strava.com/hc/en-us/...s/115000024864

MinnMan

Somewhat different issue, but I've been getting very different values from planned ridewithgps routes and the elevation recorded with my wahoo when I actually ride the ride.

Top part of the image is the actual ride, uploaded from my Wahoo to ridewithgps. Bottom part of the image is the route planned with ridewithgps. As the two maps indicate, i followed the planned route very closely.

Ride was also uploaded to strava, which indicated 32.98 miles, 1631 feet of climbing.

Go figure.