Altimeter and Barometer relations

Altimeter and barometer are both in fact just a single sensor measuring the changes of the atmospheric pressure. And since the pressure depends not only on the weather, but also on the altitude, the watch (or the user) has to decide which changes are to be measured - either the barometric pressure, or the elevation. It cannot measure both of them in the same time. By default the watch uses the auto mode, where it switches from the barometric to the altimetric functionality depending on the conditions it detects, and depending on the type of activity you do. So in your case it looks like the watch is either locked in the Altimeter Mode manually, or the auto-mode did not detect any conditions for switching to the altimeter mode.

To fix the wrong altitude, simply calibrate the altimeter. You can also enable the auto-calibration, and the watch will calibrate (using the GPS elevation, or better the DEM data if available) whenever you start an outdoor activity.

marcossaad_ said:

Calibrating manually or using GPS is getting no “recorded”.

Sorry, I do not understand what you mean.

marcossaad_ said:

as soon I calibrate it immediately returns to 20,000 meters.

I’ll try switching to barometric.

If you switch the mode to the Barometric mode, the watch will not measure the altitude at all. I suspect it is already the case in your settings. Set it either to auto, or to the Altitude mode when going out.

If you already tried the Altimeter mode, and still cannot calibrate, then I'd recommend doing first a soft-reset of the watch - pressing the Light button till it shuts down (no data will be lost). If still no change, do the master reset to factory defaults with deleting all data (settings and data will be erased from the watch, but kept in your GC account). And it still no go, contact the Support - the watch may need to be replaced.

marcossaad_ said:

Is there a way to configure the watch to record GPS elevation instead the barometric?

In Garmin Connect web, you can enable the Elevation Corrections at each activity manually. It will then recalculate the elevation profile using the topographic data

The GPS elevation is rather useless, because the accuracy of GPS elevation is much worse than at the horizontal position, with fluctuations of ÷/- 400 feet (more than 160 m). See the  article GPS Elevation Reading Accuracy on Outdoor and Fitness Devices | Garmin Customer Support

For displaying the GPS elevation you would need a 3rd part Connect IQ app. I am using my own CIQ app for some testing, and can confirm that the GPS elevation profile is of no interest. See below the overlied graphs - the full gray curve is the barometric elevation profile from the altimeter of the watch, and it is pretty well respecting the reality. The green curve is the GPS elevation plotted over it, and you can indeed see very frequent an big deviations of up to over 150m.

If used for the the total ascent, the GPS elevation would result in over 2000 m elevation gain, while in reality it was just around 100 m.

Using the Elevation Correction in GC Web makes more sense, since the topographic data is more accurate (assuming the track is recorded well)

I know all of that.

when I say it doesn’t “record” the calibration in mean : no matter how many times I enter 785m (my home) it gets back to 20000.

What mode do you use? Altimeter, barometer, or auto? Is the auto-calibration on or off? I suggest disabling the auto-calibration, setting the sensor to the Altimeter mode, and calibrating then manually. If it does not help, contact the Support.

marcossaad_ said:

I know all of that.

BTW, if you know all of that, then why do you ask how to enable the GPS elevation?

Hi, 

I didn’t mean to be rude. Sorry.

I just wanted an alternative to have real time accumulated ascent until I get new watch.

Tks for your help

marcossaad_ said:

I just wanted an alternative to have real time accumulated ascent until I get new watch.

Not sure about the F5, but on my watch I have the GPS Elevation available in the data fields for customizing the Data Screens of an activity. So you can use that for the real-time elevation information. Not the accumulated ascent, though. A Connect IQ app could do that, so check out the CIQ store - there may be one. Try for example this one: Elevation Wizard | Garmin Connect IQ