On Sun, 14 Jul 2024 at 10:16, Philippe B. <
philippe...@gmail.com> wrote:
>
> I use a Garmin Descent MK3i for diving, and I follow the procedure
> described in Subsurface to integrate data from my dive computer
> (downloading the FIT file). Although it's sometimes a bit finicky,
> everything works well, and I can find almost all my data in
> Subsurface. I say almost, because it's impossible to get the heart
> rate data! I can see it in Garmin Connect and Garmin Dive, but despite
> my numerous attempts, I can't get the heart rate data to appear in
> Subsurface...
We have had issues with the Garmin FIT file heartrate thing before -
it seems that Garmin ends up encoding it different ways depending on
random things.
It did work at one time, but even that was only when using the optical
sensor on the Garmin itself (and long ago, on the Mk1).
If you use a chest strap, afaik the data is merged after-the-fact (no
transmission under water!) by Garmin, and the FIT file from the dive
computer doesn't contain it at all.
And I have this suspicion that there may have been a data format
change even for the optical sensor on the watch itself.
Things you can try:
- does the data change if you download the FIT file for the dive from
Garmin (as opposed to downloading it from the dive computer itself)
- I can try to take another look at this, if you have a dive with
heart rate data in the Garmin app, can you send me an email with the
FIT file for that dive _and_ a screenshot with the HR data visible so
that I have something to compare to?
No promises. The FIT file data format is somewhat odd to begin with,
and if the HR data is even encoded in the file you download from the
dive computer it might be in that annoying largely undocumented
"vendor specific format".
Linus