I make sure I manually turn on Goodnight Mode when I'm going to sleep and I make sure the watch is on the outside of my wrist tightly.
I've had mine for 6 weeks and there were only two nights it couldn't detect my REM and deep sleep so it reporterd on Montionless Sleep, all other nights it detected my REM and deep aleep successfully.
I always wear my watch on the outside of my wrist.
One night I wore my watch on the inside of my wrist, thinking the base of the watch should contact the blood vessels better so the detection should be more accurate but that night sleep data was empty. I suspect it might be because, when wearing the watch on the inside of a wrist, and the palm is facing downwards, gravity pulls the watch downwards and makes the watch not contact the skin at all, hence nothing was detected.
After that night I always put my watch on the *outside* of my wrist *tightly* and sleep data has always been recorded.
I never let watch auto detect the Goodnight Mode so I can't comment in that regards.
How do you define sleep tracking was "close to perfect"?
In the past 6 weeks wearing Active 2 watch, my Deep Sleep is always detected short, around 30min mostly, last night it said I had 50min of deep sleep, this rarely happens. I read someone compared Samsing Active 2 with Fitbit and said Fitbit reported longer Deep Sleep time than Samsung did. I'm not sure whether my sleep is just bad that I don't sleep deep enough or it is that Samsung has problem detecting it.
What's your experience?
Thanks.
