I have KStars/EKOS set to get updated by the mount which is using a GPS device to set the time.
I have the mount set only to show UTC time, with no local offset and no daylight savings time. It shows the correct UTC time of 15:44, However, in KStars when I open up the mount in the Indi control panel it shows UTC as 16:44, one hour difference?
This is making my schedule start one hour early, and meridian flip start one hour early. Where would this discrepancy come from?
I think I just got to the bottom of this. It is related to DST, but it doesn't make any sense.
In my original post, I had the mount running purely on UTC time with no offset for my local zone, and daylight savings time off.
EKOS should have read that across exactly and applied UTC time but looks like EKOS was somehow compensating for DST by adding an hour.
The only combination I was able to get to finally work correctly is to set UTC time on the mount to -6 (Central time zone US). Daylight Savings time off.
Now EKOS and the mount show the same time. Somehow EKOS detects whether or not DST is in effect in your local area regardless of the time the mount sends. If I set DST on in my mount, then my mount feeds EKOS with the DST time, and EKOS compensates by adding an hour thinking it is correcting for DST time.
The correct combination of all settings in the mount, produce a problem in EKOS because only the time is sent over from the mount, and not the DST status, and it looks like EKOS is applying the DST status to the time it gets from the mount.
What I discovered through my own trial and error is that the only things that sync from the mount to KStars is the actual UTC time (with no offset and no DST setting), and your GPS coordinates. It appears KStars then knows based on your location what offset and DST to apply to your current location and then corrects the time.
This means that if I plug in DST settings into the mount, KStars doesn't know that there is a DST set, because it thinks it's only getting the UTC time, and it offsets the time by DTC even though you've already done it in the mount now making KStars have the wrong time by one hour.
I don't know if this is driver dependent or not. But that seems to be the way the 10Micron driver works. It could be different for other mounts.