F5 - Barometer settings/modes/issues

Great, let's hope it doesn't drift with time !

Yes I think the F3 is "automatic" only but if it doesn't move it should go into barometer mode.
Do you have a local weather station to get the actual MSL value ?

I have several things at home measuring air pressure :)

I got these results:

Reliable weather stations: 29.44 in Hg
Fenix F3 29.55
Fenix 5x 29.62

An error of 0.18 on the 5x is ridiculous. I hate the hassle of an RMA return, because the replacement might have good barometric pressure but a wonky OHR or something else. That's my experience in the past, anyway. Looks like that's what I'll need to do, though. On the plus side, I may end up with an extra charge cable.

My watch isn't currently charged, but back when it was, it was generally < 1 millibar of local sources, so I'm generally happy:

Home weather station: 1018
Neighborhood weather station: 1020.0
Fenix 5: 1020.4
iPhone 7: 1020.7

At this point, I think my old home weather station is the one that's off ;)

Understanding the Altitude modes more after Fenix 3 experiences.

Hi all,

I owned a Fenix 3 and returned it for the Altitude reading issues. Im now very much enjoying my experiences with the Fenix 5 but waiting with baited breath to see if the Barometric Altitude readings are OK.

I found this (wrote by WEBDAV) really useful to temper my expectations
"On the plus side the barometer module can be set to :
- Altimeter : it assumes constant weather so any changes in pressure will be altitude related
- Barometer : it assumes constant altitude so any changes in pressure will be weather related
- Auto : it selects the mode based on "movement" per the manual. Not sure if that's GPS or accelerometer movement ?"

Ive been testing the Altimeter for a few weeks and hoping people hear can help me understand if im right in my thinking :)

Question:

If I set the watch to Barometer mode am I right in thinking that the Altimeter values won't change at all unless i'm doing an activity when GPS is also used?
I've kept the watch on Auto Cal but haven't seen any Altitude changes when i've left the watch in Barometer mode (even when the watch has changed altitude). Can / is the Fenix 5 using movement to judge the mode it should use (without GPS) ?

I am struggling to understand the use for Barometer mode apart from me remembering to change it to this mode when sleeping etc and then change it back to altitude mode when i'm on the move again.

Hope someone can help me better understand this intricacy.

Thanks
Glen

that would be WEBVAN !

What you describe seems normal to me, if you want it to switch automatically between Altimeter/Barometer mode I would chose the...auto mode ;-)

Hi all,

I owned a Fenix 3 and returned it for the Altitude reading issues. Im now very much enjoying my experiences with the Fenix 5 but waiting with baited breath to see if the Barometric Altitude readings are OK.

I found this (wrote by WEBDAV) really useful to temper my expectations
"On the plus side the barometer module can be set to :
- Altimeter : it assumes constant weather so any changes in pressure will be altitude related
- Barometer : it assumes constant altitude so any changes in pressure will be weather related
- Auto : it selects the mode based on "movement" per the manual. Not sure if that's GPS or accelerometer movement ?"

Ive been testing the Altimeter for a few weeks and hoping people hear can help me understand if im right in my thinking :)

Question:

If I set the watch to Barometer mode am I right in thinking that the Altimeter values won't change at all unless i'm doing an activity when GPS is also used?
I've kept the watch on Auto Cal but haven't seen any Altitude changes when i've left the watch in Barometer mode (even when the watch has changed altitude). Can / is the Fenix 5 using movement to judge the mode it should use (without GPS) ?

I am struggling to understand the use for Barometer mode apart from me remembering to change it to this mode when sleeping etc and then change it back to altitude mode when i'm on the move again.

Hope someone can help me better understand this intricacy.

Thanks
Glen

Please excuse my ignorance but this is the first watch that I've had altimeter/barometer settings available. I had issues with the watch not counting floors when I go upstairs and I read a post somewhere that suggested setting the watch mode to Altitude, which I did and to be quite honest didn't see much difference in the accuracy of counting floors, however the altimeter seems to be all over the place. I went to bed one night having manually set the altimeter to 98ft and when I woke in the morning the altimeter reading said 324ft. Having read the post above would I be better setting the watch mode to "auto"? I'm not going mountain climbing or anything I just want the watch to be reasonably accurate and not show huge variances for my usual locations such as home or work (could these variances have been down to air pressure changing?)

Rick

Please excuse my ignorance but this is the first watch that I've had altimeter/barometer settings available. I had issues with the watch not counting floors when I go upstairs and I read a post somewhere that suggested setting the watch mode to Altitude, which I did and to be quite honest didn't see much difference in the accuracy of counting floors, however the altimeter seems to be all over the place. I went to bed one night having manually set the altimeter to 98ft and when I woke in the morning the altimeter reading said 324ft. Having read the post above would I be better setting the watch mode to "auto"? I'm not going mountain climbing or anything I just want the watch to be reasonably accurate and not show huge variances for my usual locations such as home or work (could these variances have been down to air pressure changing?)

Rick

Altimeter mode means that it locks the baro reading, every change in baro pressure being processed as a climb/descent, hence the altimeter reading being all over the place. Barometer mode means that the altimeter is locked, therefore every change in barometric pressure is accurately measured. Alti mode should be used when you move around, climbing a mountain, driving to work etc, while baro mode should be used when in the same spot for a prolonged time (e.g. at work or smth similar). Auto mode works quite well. The watch has only one sensor, it measures only the fluctuations of the baro pressure, that is why you have to tell it (or leave it on auto mode) whether you're changing elevation due to movement or the weather is changing. The only case when you have to calibrate the altimeter very often is when you re up the mountain, on your way up or down the pressure changes due to elevation change, as well as changing atmoshperic conditions, therefore it s hard to tell which one has the influence.

Thanks Webvan (not Dav ! :) )

Yeh what you said makes sense to use the Auto Mode.

I've had strange Altimeter changes overnight in Auto mode, do you know what the watch is doing in Auto Mode? I'll pop the watch back into Auto mode again and see what happens to the Altimeter readings overnight over the next few days

Its a lovely watch and I guess Im just trying to understand if its faulty so any extra info would be amazing.


Thank you
Glen

I don't think it uses the accelerometer to detect movement so it has to rely on the speed of the change in pressure. If it's very fast it will assume it's a change in altitude

And what about auto-calibration? Well I think it only kicks in when you start an activity.

Thanks Webvan (not Dav ! :) )

Yeh what you said makes sense to use the Auto Mode.

I've had strange Altimeter changes overnight in Auto mode, do you know what the watch is doing in Auto Mode? I'll pop the watch back into Auto mode again and see what happens to the Altimeter readings overnight over the next few days

Its a lovely watch and I guess Im just trying to understand if its faulty so any extra info would be amazing.


Thank you
Glen

There will always be changes to the altitude, even when the watch is just sitting there. Altitude is derived from the barometer, and changes in weather (pressure differences) will have you gaining or losing altitude even though the watch is stationary.

Unless it's changing drastically overnight, like hundreds of feet, it's likely not defective. A few feet here or there, and even 10-20 is pretty normal, and even more so if the weather is changing.

http://elevationmap.net/

Use that for finding elevation at home, work, and your normal fitness related starting points. Make a note of each, and refer to them for calibration when at those places. There, now you've calibrated to a better-than-guessing altitude.