Altimeter and barometer are one of the core features of any multisport/outdoor devices and many activity stats involves data from that sensors.
I know no barometer or altimeter can be perfect, even ones which are mounted in planes, weather stations etc. (I'm making my PhD in Physical Geography and have lots of experience with such tools and data).
But in my opinion there is a plenty of room for improvements (software-wise) how altimeter/barometer works in "Auto" mode on forerunner 955 devices (and I doubt on the other series too, e.g Fenix, Instinct etc.).
For example: my home elevation is 547 m.a.s.l. Last 2 days were pretty windy (with 29-37 km/h gusts). In general, that means there is difference in atmospheric pressure, which causes winds to occur (air moves form higher to lower pressure area). Because of complex terrain and climatic conditions my region is very prone for fluctuations in air pressure, temperature and generally in weather. My forerunner 955 bit struggles to determine correct altitude in such situations. Last two days I'm sitting at home, working on some papers, so my location is mainly static, so is my altitude. Despite of this, my altimeter after manual calibration drifts pretty much (not in crazy scales, but changes are fast (in every few or tens of minutes) and significant). See attached photo for 4 hrs plot. Altimeter settings are as follows: Sensor mode - Auto, Auto Cal. - on. (I know that I can change to barometer only mode, but my purpose here is to test how correctly auto mode can determine actual elevation and pressure changes). I also cleaned watch and did fridge test to check how correctly barometer itself works. There are test results:
Before fridge After 20 mins in fridge After 10 mins from fridge test
Air pressure: 1013.5 hpa 1013.1 hpa 1013.3 hpa
Altitude: 555 m 558 m 557 m
Temperature: 30 c -12.9 c 14 c
Results indicate that sensor itself (barometer) works more than fine (it is not strongly influenced by external factors except pressure). Also during activity it tracks elevation gain/loss pretty ok.
I have read lots of threads here about similar topics and I know that those are more or less known "issues" at least for users. Also, I understand that it's not easiest thing to program barometric altimeter to always be in spot, but as long as this watches implement plenty of other sensors, such as: gyroscope, accelerometer, thermometer, electronic compass in their multi-sensor platform, I think this sensors should work more coordinated.
Overall I'm ok with watch, own for one month now (my first ever Garmin wearable, coming from gpsmap series) and did not had any major issues, but at the same time I think that software needs more development in some areas. I'm on 16.09 beta now, but can't see any major fixes in any direction compared to 15.19.
Sorry for bulk writing and your opinions and experiences would be very interesting.
Thank you! :)
