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Auto Calibrate Elevation to Location? Baro Altimeter?

gaijin
over 9 years ago
Here's another one:

On my Edge 800 it is possible to have the Elevation Auto Calibrate to my starting location. I saved the location, and every time I start a ride from that location I get the pop-up that says the Elevation has Auto Calibrated to that location.

I can not find the same feature on my Edge 820. As a workaround, before starting a ride I go to Navigation>Adjust Elevation and set the elevation immediately before a ride. It is a bit cumbersome, and doeasn't seem to do as good a job as the 800 in managing Elevation over the course of the ride.

The 800 has a barometric Altimeter which means it does not take all the Elevation data from GPS. This has proven very reliable.

The specs for the 820 say it also has a barometric Altimeter, but the recorded Elevation data look like all the data points come from GPS.

Does the 820 indeed have a barometric Altimeter?

TIA for any help.
  • Former Member
    0 Former Member over 9 years ago
    same in Moldova, my garmin shows altitude about 20-30m lower than actual value.
  • 0 over 9 years ago
    The same in France:
    -No auto calibrate elevation from a known location.
    -Elevation is always 20 to 30 meters from the real elevation
    Garmin can you take care of this issue
    Thanks
  • 0 over 9 years ago
    Set mine up as per the manual - doesn't work - I should 55m above sea level at the location - it shows -6m even after shutting down and restarting. I set the same thing on my Edge 1000 - works fine.
  • Former Member
    0 Former Member over 9 years ago
    Auto-calibration and elevation drift

    Did that. Labeled the location "Start" and edited the Elevation to be 4553 feet.

    I could find no mention in the manual of Elevation adjusting to location. My experience is that the Edge 820 does not have this feature.

    TIA


    I agree. I believe auto-calibration by location it is at this stage a missing feature, which is quite useful in my 5y old 800. In the 800 I had usually to mark 3 or 4 locations near my usual start in order to compensate for small GPS deviations (my usual start location is in the middle of tall buildings, so GPS may have slight variations here), but with this minor fix auto-calibration worked almost always OK.

    Concerning the altitude drift mentioned in other posts, I did not analyze yet in detail altitude issues in the 820. My experience with the 800 is that we always have some elevation drift between the start and end of the course. I believe the main reason for this is that barometric altimeters are always affected by temperature. While some temperature compensation can be made by software (I am not sure if Garmin uses it), this compensation is always highly dependent on other local conditions and difficult to compute accurately. My past experience with the 800 also shows that the altitude drift during a course increases with temperature variation between the start and end of the course. But I will take my 800 in parallel with the 820 in my next ride and I will check if the drift between the two units.
  • 0 over 9 years ago
    Height of my home location = 5m.
    The Garmin 820 says -55m.
    So far all of you have a difference of minus 50 to 60m. That is a lot and must be corrected somehow by Garmin.
  • Former Member
    0 Former Member over 9 years ago
    I could find no mention in the manual of Elevation adjusting to location. My experience is that the Edge 820 does not have this feature.


    Page 20 in the User Manual pdf.
  • 0 over 9 years ago
    Page 20 in the User Manual pdf.


    I used that and it works fine for a couple rides but then goes back to reporting at least 30-40 meters below actual altitude
  • Former Member
    0 Former Member over 9 years ago
    I used that and it works fine for a couple rides but then goes back to reporting at least 30-40 meters below actual altitude


    You're lucky it's never yet worked for me on my 820 (worked fine on my 810).
  • Former Member
    0 Former Member over 9 years ago
    Page 20 in the User Manual pdf.


    Yes, manual calibration is available. What it seems to be lacking is auto-calibration, a feature that is at least available in the Edge 800: you define/save a location and its altitude once (for example, your usual start location), and from here on the device auto-calibrates to that altitude whenever it is near that reference location. So far as I have seen up to now, I have to calibrate the altitude of the 820 at the start of all rides.
  • Former Member
    0 Former Member over 9 years ago
    Yes, manual calibration is available.


    But that's the point, it doesn't work, I tried again today, set the elevation to 260ft pressed Start, the data recorded in the .fit file started at 107ft.