Auto elevation calibration

Wow, that's an interesting feature indeed described under the link! Why do you think it should be related to the ABC widget? It's more likely that it's a product of the altimeter calibration as I read it. I'll try it on my VAHR, calibrating the altimeter under the GPS on, will report back.

You are right, there is no relation between ABC widget and elevation calibration. I made some inquiries about it and it seems that it a device based feature. If the device supports this sort of calibration, then it takes the height from known location if you are close to it. So I made a GPX with several locations in it, uploaded it to VA3 to NewFiles with no success. It is quite understandable, that watch could not transform GPX to FIT (however Edge 510 can do that). So I converted the GPX to FIT, uploaded it to NewFiles again (uploading it directly to Locations folder does not work) and voila - new locations appeared in the VA3 in saved locations. Sadly, the saved locations are NOT used for elevation calibration (unlike in Edge or Fenix). When an activity is started, the calibration is still done via vague GPS. Since VA3 has a barometer, it is a pity it could not use its full potential, by offering a simple a hassle-free way of calibrating it.

I actually tried this on my VAHR, only I used altitude calibration in the sensor menu instead of ABC. The result is quite surprising - the feature works but in an unexpected way. Apparently, it links barometric pressure to location rather than altitude. In my case, I calibrated the altitude to the real 176 m near my office the day before yesterday, and then both yesterday and today the watch re-calibrated itself from 190 and 196 m to 228 and 227 m immediately as I approached the place of calibration with GPS on. Readings from the Ambient pressure widget today:

Before the "location" calibration
ambient pressure 745.3 mm
altitude 193.6 m
barometric pressure 765.2 mm

After
ambient pressure 745.1 mm
altitude 227.4 m
barometric pressure 767.7 mm

Will monitor further if that's the barometric pressure that gets sticky, or if it's just an offset from the manually calibrated 176 to 227-228 m.

I tried to reach Garmin support to get help with this. Here is a transcript.

Garmin agent:There is not a way to do this in the vivoactive 3 unfortunately. This cannot be compared to outdoor devices such as the fenix or Edge series of devices

me:Hmm. Since it's just a really simple software feature, I take it that Garmin for some reason does not want to implement it into VA3.

Garmin agent:I cannot advise that as I am not an engineer on the device unfortunately. ... The vivoactive 3 has limitations and it does not have the ability to do this unfortunately.


Well, quite disappointing. I really see no reason why it should not be possible. VA3s have all necessary sensors (GPS, barometer) and software background (custom locations, simple navigation). You just need to put them all together.

So it seems to me that Garmin does not WANT to do it.

It's quite standard, Garmin impairs the functionality of their product line from top to bottom despite the hardware is often the same. It's just business, market segmentation and stuff. E.g., in some early FW releases Vivoactive HR used to support structured workouts for some short period of time...

You could try this on your VA3 in the same way - just turn on the GPS, and then go to the sensor menu in the settings and manually calibrate your altitude. Maybe it does the trick not in the way my Vivoactive HR performs, but correctly.

Sadly, the saved locations are NOT used for elevation calibration (unlike in Edge or Fenix). .

Saved locations are not used either on Fenix. At least not my Fenix 3. And in my opinion, it would be silly of Garmin to do that.

You must remember that a lot of saved locations were recorded by the watch, with the same imprecise GPS altitude measurement that you are trying to avoid.

The way it works is that I set my altitude manually in the altimeter, while the GPS already has a fix. This means that I have to start an activity which uses GPS, go back to the watch screen so I can reach the altimeter widget, and from there set the altitude while the GPS is still running in the activity.

When I do this, the watch sees that it has received a known altitude with a known location. So it will put this altitude/location pair into a hidden table which I can't see. I don't even know how many entries the table can hold, or if it will delete the oldest entries when it runs full. So it is hard to know exactly what is going on.

When I have done the above, and I later start a new activity with GPS, I just need to make sure that the GPS has a fix, and that I come within approx. 25 meter of the stored location, before I press Start. Then the elevation field (easy to see if I have this field enabled in a data screen in the activity) will suddenly jump to the stored value.

If I go out of the activity without pressing Start, the altimeter will switch back to its old setting. If I press Start before the watch has discovered that I am at the stored location, it will not try to calibrate the altimeter, even if I later during the activity come close to the stored location (which I am grateful for, since I would not want a sudden elevation jump in an activity).

The above sounds complicated, but it works really well, and I don't have to think much when it is set up. I step out of my front door, go into an activity app, wait for green ring and press Start. Then my run will start at 40 meter altitude every time.

I just partly agree with your description and argument.

"Saved locations are not used either on Fenix. At least not my Fenix 3. And in my opinion, it would be silly of Garmin to do that.

You must remember that a lot of saved locations were recorded by the watch, with the same imprecise GPS altitude measurement that you are trying to avoid."

When you save a location you have the option to edit it, thus you can easily set the known elevation of a saved waypoint, just as the same way you described "the saving after the GPS fix".

My other point is maybe related to F5+, too, and F3 works in a different way

I think even omitting the elevation data of saved waypoints (saved locations) would not cause a big problem, and the method you described would be perfect, but there is another problem, at least for Fenix5+ series (tbh I think it is the same problem at least for F5 and F6 series, too. I unfortunately dont remember how my F3HR handled it).

What I mean is that if you from time to time manually calibrate the elevation of your watch, even without any GPS fix, it simply overrides the calibrated elevation of the stored "hidden saved location" you mentioned. In other words independently from where you were exactly when you made the last elevation calibration it has a higher priority than your GPS fix-based calibration.

So practically your run will start at 40m altitude unless you re-calibrate your watch after the last GPS fix-based calibration.

I tested it at least 5 times with my F5+ and it works how I described above. And this way is stupid.