Doubt about Suunto 9 Baro altimeter/barometer calibration

[A Former User]

Thanks @mario_b! Now I can understand for what on 1st try the reaction not was immediately and I got better results on 2nd try.

it messures every 10 sec

Wow, I imagined that should be a lower value, by this I expected a faster response in the update of the altitude readings. But really not need a faster update in watch mode, because for this I have the Sport Modes.
Thanks to everyone again!

[Dimitrios Kanellopoulos]

@flypg it counts higher than 3-5m variations in 12 minutes. If you would go a bit more low then both devices should react the same.

That is to wipe out pressure changes as we talked before

[Dimitrios Kanellopoulos]

https://www.suunto.com/en-gb/Support/Product-support/suunto_9/suunto_9/valid-for-barometer-version-only/outdoor-insight/

If you are at a constant altitude (less than 5 meters of vertical movement within 12 minutes), your watch interprets air pressure changes as weather changes and adjusts the barometer graph accordingly.

[A Former User]

Thanks again to everyone!

Yes @Dimitrios-Kanellopoulos, this explains that on all my attempts I generated a altitude variation > 30m in less than 12 minutes (because I went up and down several times more than the 2 tests).
The only that is not totally clear is the variation of 1st try that the S9B not registered this +4 of when I went up.

[johann.fuehrer]

@Dimitrios-Kanellopoulos I have a Spartan Ultra: I’m sitting at the moment in my office at 214m above sea level. I know from the weather station on my altitude just some 2km away, that we have 2015.4 hPa at 30 C temperature. My watch shows me 2021 hPa. If I like to have a correct pressure reading, I would have to change the altitude to 165m. SO how can I bring this together to see correct altitude AND correct pressure?

[A Former User]

@flypg said in Doubt about Suunto 9 Baro altimeter/barometer calibration:

If you are at a constant altitude (less than 5 meters of vertical movement within 12 minutes), your watch interprets air pressure changes as weather changes and adjusts the barometer graph accordingly.

I published this myself a couple of weeks ago

[Dimitrios Kanellopoulos]

@johann-fuehrer is it sea level pressure? Can you give me now a coarse location (town)? I can look that up for you

[johann.fuehrer]

@Dimitrios-Kanellopoulos
https://www.zamg.ac.at/cms/de/wetter/wetterwerte-analysen/wien/luftdruck/?mode=geo&druckang=red

It’s Vienna and “Wien Unterlaa” is the station I mentioned …

https://www.zamg.ac.at/cms/de/wetter/wetterwerte-analysen/tawes-verlaufsgraphiken/wien_unterlaa/luftdruck/?mode=geo&druckang=red

[johann.fuehrer]

@Dimitrios-Kanellopoulos … and yes, it’s seal level pressure. Local pressure is about 993 hPa

You can switch in the pressure chart caption!

[A Former User]

@Dimitrios-Kanellopoulos said in Doubt about Suunto 9 Baro altimeter/barometer calibration:

Lets keep an eye on this.

I think that I understood some extra… On my workings days I use a lot the stairs. This results in variations of more than 5m in less than 12 minutes, that result that my watch change to alti-mode. When I have a weather change the pressure variation is assinged to the altimeter and by this I see this big changes on the altitude… can be possible or I´m totally wrong?

[Dimitrios Kanellopoulos]

@flypg On watch mode there is no mode

[Dimitrios Kanellopoulos]

@flypg for indoor activities there is automode

[Dimitrios Kanellopoulos]

@johann-fuehrer yeah I see the same from my sources indeed looks like the watch is about 6hpa wrong right ? There is a tool that can calibrate the abs pressure but unfortunately only support can do that.

[johann.fuehrer]

@Dimitrios-Kanellopoulos is there any support here in Vienna which can do this?

[Dimitrios Kanellopoulos]

@johann-fuehrer I am not sure I am very far away (in terms of internal comms) with support stations etc

[A Former User]

@Dimitrios-Kanellopoulos Thanks, I think that I need re-read all the post again

[mario_b]

@johann-fuehrer ZAMG does not report QNH ambient pressure. They take the temperature into account. Compare your pressure with the Vienna airport QNH value: https://aviationweather.gov/adds/tafs/?station_ids=LOWW&std_trans=translated&submit_both=Get+TAFs+and+METARs
They are reporting every 30 minutes. (Time is shown is UTC so don‘t get confused)
You can only compare the ZAMG value when it is around 15 degrees Celsius in Vienna.
Greetings from Tirol

[Dimitrios Kanellopoulos]

@mario_b oh. Thats why the variation!

[mario_b]

@Dimitrios-Kanellopoulos thats why i allways ask, which ambient pressure is used to compare. because QNH is allways calculated with 15 degrees.
and since my a3p is back from service, its spot on with every QNH value around me.

[freeheeler]

@mario_b
15’000km service?!
what was wrong with it?