Altimeter is calibrated when using treadmill

Former Member over 6 years ago

I am experiencing calibration of the altimeter when using treadmill. The watch uses last known calibration, even if I am several kilometers away from the place where the watch was calibrated.. this means that the GPS is not activated. So why do the calibration happen? If the watch is set to manual calibration of the altimeter, this do not happen...

anyone else who has had some issues?

running fw. 11.00, same issues where also on the latest betas, pre fw 11.00.

best regard:-)

0 AllanOlesen67 over 6 years ago

Is the watch connected to your phone when this happens? Does the phone share its location with the watch?

My 5X+ will at night calibrate the altimeter, using the phone's 2D location, combined with a lookup of that location in the built-in altitude map of the watch. Perhaps your 5X (which I assume also has altitude maps) is doing the same when threadmill running.

0 Former Member over 6 years ago

Yes my watch is connected to the phone(garmin connect, android) but I do not think that the watch has this calibration feature as the 5+. It is only manual or automatic(at the start of a activity).

And yes. The watch has a DEM on board but not for calibration of the altimeter, unfortunately. Hope they will implement this feature.

best regard

0 AllanOlesen67 over 6 years ago

Hope they will implement this feature.

How do you know that they haven't already implemented a part of that feature without telling you?

If I were you, I would do a run with my phone disconnected and see if the watch still behaves in the same way.

0 Former Member over 6 years ago

Okay. Will disconnect the phone next time to test out

0 rickj2903 over 6 years ago

This is really interesting, I have had problems with auto calibration since the first day and the first unit (April 2017). Sometimes the auto cal sets the elevation to 98m despite the correct elevation being 24m. I always wait for the full green GPS lock circle before starting an activity (usually outside). I have now resorted to having elevation as a screen which I check before commencing the activity, if its wrong I manually calibrate the elevation. I thought that the 98m was some kind of default because the watch hadn't got an accurate GPS signal but having read your post I've realised that 98m is the elevation of where I work and usually where I last manually calibrate the watch before coming home and starting an outdoor activity. I am using my watch connected to a iPhone 6.

0 AllanOlesen67 over 6 years ago

The Fenix 3 and several later models has a hidden functionality:
When you start an activity at a location where the altimeter has earlier been manually* calibrated (with the GPS active, so the watch knew its location), the watch will calibrate to the same altitude again, instead of calibrating to the GPS altitude.

This makes a lot of sense. For example if you have earlier calibrated your altimeter at home before starting an activity once, you will probably want the watch to calibrate your altimeter to the same altitude again every time you start an activity from home.

I wonder if your F5X also has this functionality, and there is a bug in it so it somehow thinks that you are at your work location when you start an activity without GPS.

(*: It seems that my F3 went a bit further and also remembered its auto calibrations from GPS altitude at specific locations. So if the elevation had been calibrated wrong once because GPS was imprecise, it would be calibrated to the same, wrong elevation every time I started an activity at that location. This was a bit silly, but it was easily overridden by once making a manual calibration at that location with the GPS active. Then all future runs from that location would use the manually calibrated elevation.)

0 Mistamb over 6 years ago

i have here problems too since V11.00. i have autocalibration on.
- the actual baro-alti value is nearly correct. start an activity without gps. sometimes it jumps to an previous defined value. even if it does not should calibrate without gps. (restarted the watch and it worked.)
- the actual baro-alti value is nearly correct. startet an activity with gps. show's me a good value to the know elevation. Autocalibration does not work. it stays on the value (restarted the watch and it worked.)

0 Mistamb over 6 years ago

another question? does anybody know, where the calibrated locations are stored? i mean in which file? if it is possible to delete it, whithout reseting the whole watch?
so for testing, that there is no gps postition with an elevation is saved from previous altimeter calibrations?

thanks, for the info!

0 AllanOlesen67 over 6 years ago

another question? does anybody know, where the calibrated locations are stored?

No, I have never seen this information, though I have read almost all altitude related threads for a long time now. As I wrote earlier, it is a hidden feature which has never been documented by Garmin. I have not even seen them confirm that the feature exists.

But in the original thread in the Fenix 3 forum where the behaviour was documented by fellow users, I think someone tested "how much" one would have to reset the watch to delete the table and found out that a full factory reset was needed. But I would have to dig up this thread again to be sure.

0 Former Member over 6 years ago

I have tried to disconnect watch from the watch before I start an activity. The altimeter still calibrates to last calibration. What seems to "fix" this, is rebooting the watch before using treadmill. Hope this small but annoying bug gets fixed. Btw. My fenix 3hr do not behave like this.