Last night before I went to bed my compass app was reading correctly. This morning it was still reading correctly. Up and down the stairs fetching cups of tea etc it was responding to minute changes in elevation - a very sensitive and accurate barometric sensor no doubt. As I write - it’s still reading correctly. I’m sure this issue will have a good outcome once the Apple experts get their heads around what’s going on.
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Series 6 Altimeter Discrepancies
- Thread starter StumpyBloke
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This morning after disabling GPS (both on phone and watch), BT and wifi (to be sure no connection established) and re-enabling before going to bed the reading is perfect. The only thing changed is that MyAltitude is not getting altitude (shows ---) but the compass, yes, and it's accurate. More confused...
That’s very similar to what happened to me and now this afternoon the compass app elevation is still correct inside the house after leaving my watch in Airplane Mode overnight and it still is. As you say even more confused. I’m just about to switch Airplane Mode off again to sync an activity - I wonder what will happen next. 🤔
Mine is still accurate and has been all day. I’m beginning to think it may be something to do with the watch using it’s own GPS at some point / during an activity which calibrates the elevation using the GPS coordinates independent of the barometric pressure. Something I discovered today about my Garmin watch on auto calibration requires a pause (30 secs) between acquiring satellites and pressing start on an activity to allow the elevation to be re-calibrated. I went outside in the garden and it worked. I’m beginning to think that there’s nothing broken here that either a software fix or better instructions can’t fix. Of course we shouldn’t be in this position (pardon the pun) but I think we’re homing in on it.
that is the option of auto-calibrate during an activity. It also has the option to auto-calibrate when not in an activity and this is the one that never works properly.
36 hours on now and my AW 6 is still reading correctly. I wish I could be sure what I did to make that happen.
Last night mine was still reading at 375 m. And no matter what I did, disconnect Wi-Fi, disconnect mobile etc it wouldn’t change. I loaded up the compass app on the iPhone and that showed 90 m elevation and then when I looked on my watch it had corrected itself and it is now exactly right.
So I still maintain that the lower the air pressure the more inaccurate the altimeter is but it looks as though mine just got stuck last night.
So I still maintain that the lower the air pressure the more inaccurate the altimeter is but it looks as though mine just got stuck last night.
We will beat this! Hopefully less confusing as each day goes by after we try something else. Of course it should simply be plug and play. Barometric pressure up here is creeping up so I’ll have to wait until it goes down to see what happens. In Scotland that won’t be too long 😅.
An update on my AW 6 elevation. Into the fourth day now and it’s still reading very accurately - no glitches. The barometric pressure in my area has gone up quite a bit over the last 36 hours. The watch elevation responded accordingly, indicating a reduced elevation and then periodically adjusted/re-calibrated so that it is still reading 60 mtrs at my house which is correct. I did a two hour activity yesterday in Airplane mode without my IPhone on me and the elevation trace was good. I’m waiting now to see what happens when the barometric pressure goes down again to see how the watch reacts.
Further update on my AW 6 elevation readings. The Barometric pressure increased quite a bit overnight resulting in my elevation via the compass app reading 30 mtrs this morning - approx 30 below what it should be. I went for a walk using WorkOutDoors App with my watch still connected to my phone. Elevation (absolute above sea level) worked perfectly throughout the walk using this App. When I got back the elevation reading via the compass app was still reading 30 mtrs and had not re-calibrated. I’ll head out in a while using my watch on Airplane mode and no phone connection to see if that makes any difference when I get back. If it doesn’t then it would appear that the Compass App is at fault. The correct information is definitely in the watch as WorkOutDoors App has no trouble finding and using it. This WorkOutDoors App is really quite amazing and knocks spots off anything else I’ve ever used. This is the App that the Apple App should have been.
Interesting! - Further update to my AW 6 Compass App elevation data. I went out for another walk using the WorkOutDoors App but this time in Airplane mode and no phone connection. Elevation tracked correctly on WO App but when I got back my Compass App elevation was still reading about 30mtrs under and hadn’t re-calibrated. I sat playing with the watch and tried resetting calibration data - still no change. Then.... I had been using my watch this morning with Motion and Fitness Tracking turned off (experimenting with battery usage) so I turned the the tracking back on again and my Compass App elevation immediately jumped back up to 60mtrs - correct reading. Now - I’m not sure whether it was the action of pressing Reset Calibration Data and then turning on the Motion & Fitness Tracking that corrected the elevation or whether the Reset Calibration played no part and it was just turning the Motion & Fitness Tracking back on that corrected the elevation. Either way I feel like I’m homing in on it now. Hope that all makes sense.
I will add my two pence worth to this. Now the air pressure has gone up, currently 1020hPa, my elevation reading is correct but the +/- is way out at 290m. It’s been like this for days.
Aye we’re not there yet in understanding exactly what’s going on. My elevation is correct at the moment with an accuracy of + / - 10 mtrs. I’m gonna watch what happens as the pressure changes and see if I can ascertain exactly what I did to cause the elevation to re-calibrate.
Just makes it all look so easy doesn’t it. Every bit of info you could ever need in a very intuitive app that you can shape whichever way you want. Apple could learn a lot from that.
Further update to my AW Compass App elevation data. As the local barometric pressure increased the elevation indicated dropped overnight as expected reaching 45 mtrs (15 under) this morning + / - 15 mtrs. As soon as I acquired GPS via the WorkOutDoors App, not in Airplane mode and still connected to my IPhone, sat inside my house, the Compass App Elevation re-calibrated/corrected back to 60mtrs + / - 5 mtrs. So far that’s been several days of working correctly or close enough for me. I’d say I’m 90% confident in it 😬.
Same here - after 9 or 10 days the elevation has always been within about 3 mtrs on the Compass App at my house regardless of the + or - accuracy. I’ve actually taken it off as a complication now rather than keep checking it a gazillion times a day. When using Work Outdoors it is very accurate - probably more accurate than either of my Garmins.
Have you got Fitness Tracking activated under privacy on watch app and compass calibration plus motion and fitness calibration under System Services on your Phone / plus have you activated the GPS fairly regularly. I’m not 100% about all these things but they are all settings that I played with on mine when it suddenly sprung into life and it’s been right ever since.
Interestingly I thought that my watch was only correcting the elevation (for changes in Barometric Pressure) when I acquired GPS for an activity but I noticed just now that it corrected it without any intervention at all. 10 days now and pretty accurate all the time off activity and very accurate during activity.
Finally after quite a lot of days with relatively high barometric pressure and fairly regularly corrected elevation readings (via Compass App), my local barometric pressure is falling and as it passed 1000 mbar the elevation corrections appear to have stopped and the actual elevation readings are getting worse again. Reading is currently 112 mtrs with an accuracy of + / - 25 mtrs. The actual elevation is 60 mtrs. Keeping an eye on it but unless there is a sudden correction now below 1000 mbar then I agree with StumpyBloke with his observations so far. The current elevation reading is not nearly within the + / - accuracy.
since i'm doing all my outdoor walks now in airplane mode on the watch, the gps tracks, elevation, speed, pace data is perfect. As a side-effect of that, the compass app on the watch shows always exact elevation, +/- 5 or 10m, even days afterwards. Heck, even VO2 data started to appear for all my walks 
procedure: go outside (with phone or not doesn't matter), watch settings-airplane mode-make sure it disables BT as well besides Wifi, back to homescreen, slide up, select airplane mode, watch workout app-outdoor walk, 3-2-1-go, wait 4-5 seconds, start walking. At end of walk wait 2-3 seconds, press end workout, press crown go to homescreen, disable airplane mode, go back to workout app-click DONE.
procedure: go outside (with phone or not doesn't matter), watch settings-airplane mode-make sure it disables BT as well besides Wifi, back to homescreen, slide up, select airplane mode, watch workout app-outdoor walk, 3-2-1-go, wait 4-5 seconds, start walking. At end of walk wait 2-3 seconds, press end workout, press crown go to homescreen, disable airplane mode, go back to workout app-click DONE.
Air pressure is currently at 1014 hPa where I am with the elevation reading of 97m +- 5 m (it should be 87m). I will keep an eye on it changing because the weather is taking a turn for the worse around here (starting to get wet again) and I think it’s going to do what yours does and as the air pressure drops the readings but will become more inaccurate.
It is still gobsmacking to me that Apple clearly didn’t test this.