New FR945: Horrible sleep tracking

That's my problem, too. Falling asleep and wakeup times are mostly correct but I have gaps in several nights, sometimes for an hour or so. And I can't belive I have hardly any time with deep sleep. My old Fenix 3HR showed me about 30-50% deep sleep (there was no REM phase though). 945 only shows several minutes if any.

I check sleep data each morning. Sleep Times are OK for me. I have very regular sleep timing and this is even part of my settings.

On the other side the sleep phases are completely different between my old 735XT and my new 945. With my 735XT I had  more than 3 hours deep sleep and I was happy with it, because it is a sign that my physical recovery works well.

Now with the 945 I have much less than 30min deep sleep and ~ 3hours REM sleep (REM did not exist on the old 735XT).

Now I’m completely confused. According to the 945 I get a lot of mental recovery (REM), but nearly no physical recovery (Deep Sleep).

After seeing these completely different results from 2 Garmin watches, I’m not sure if I can trust the sleep phases.

I don't sleep often with my 945 but a few times that I did, I noticed that sleep tracking within the predefined sleep hours was correct. Unfortunately, 945 seems not to account at all for mid-day naps and struggles with sleep times outside of predefined sleep window.

Both 945 and my earlier 735XT at much worse at sleep tracking vs. my 2015 fitbit ChargeHR.

Do you check them also later?

I've noticed that the time is right when I wake up, but then some backend processing happens and I get too much sleep times :D 

Mine has been quite off too -- often not realizing that I was asleep until about 90 minutes after I actually fell asleep.

However, yesterday I went into the user settings for the watch and I realized that I had set my "normal" sleep times about an hour later than my actual normal sleep time. I corrected this setting and then today, the watch's record of my sleep was almost exactly right.

My suspicion is that whatever heartbeat and behavioral cues the watch is looking for to signify sleep don't start getting checked until you hit the time you've identified as your normal bed time. 

Can someone from Garmin or Firstbeat confirm this?

In any event, if your watch is recording strange sleep times, check your bedtime setting to see if you've set it for the times you actually go to bed. Might help.

firmware 2.50.

ONLY use for training (run, swim or bike).

NEVER used in a nap or sleeping.

Each day it shows "sleep"... sometimes from 21:30 to 6:30.... sometimes from 23:00 to 4:00.... the watch is always QUIET in a table and NOTHING moves it.

any clues?

I have exact the same problems.. Like this night i was awake for two hours in the middle of the night says Garmin... Without actually knowing i was awake. What a miracle. Sleeptracking with fr935 was the last 2 years very good. Fr 945 fails almost every night... 

That doesnt explain errors in the middle of the night. I mean mine says that i am awake when i sleep in the middle of my sleep. This has nothing to do with the settings for bedtime.

I will also add mine is fine. I do find that if you wake up but don't get up it thinks you are still asleep but overall I am happy with the tracking.