How can the height measurement be improved?

I have an Instinct Solar.

When I take a run with the start and finish at the same point I notice that the elavation valves do not correspond.

I am talking about at least 10 meters difference on a 10K run in a level enviroment.

(I am thinking of using the start and finish values to correct all the intermediate values)

  • When I take a run with the start and finish at the same point I notice that the elavation valves do not correspond.

    That's normal, because in the meantime both the atmospheric pressure and the temperature changed, and both of it have impact on the pressure sensor reading. 10m difference on a 10K run, is an excellent result, and personally I would not bother about it at all, but if you really want to improve the reading, then I recommend going out some 10 or better 20 minutes before the activity, and warming up. In this way you limit the temperature changes (both the change of the room to outside temperature, and also the heating up of the watch by your body). Start the activity only once you warmed up, because it is at the moment of the activity start, that the watch calibrates the altimeter (if auto-calibration enabled). You can also calibrate manually, of course.

    And then, if the activity is longer, you can stop occasionally and calibrate the altimeter using the DEM method (you'll need a phone with mobile data for that). Do not use the GPS calibration - the vertical accuracy of GPS is miserable (~ +/- 150 m)!