Hi @Tech@ZWO -
I was working on my own driver for the AM5 mount, and I started running into some very strange behavior with regards to sidereal time being incorrect. So I took a look at the ASCOM driver behavior in order to figure out what I was doing wrong. After reviewing the logs, it appears that +/- of Time zone and Longitude need to reversed in order for the sidereal time to work as expected.
I am running the 1.5.2 firmware and the 6.5.20.0 ASCOM Driver.
I am seeing a strange behavior in the logs of the ASCOM driver. It appears that the +/- for Time zone and also Longitude are reversed in the serial commands vs what I would expect.
For example:
If I set my site latitude to +30 * 19:47, longitude to -98 * 00:00, and given that my computer clock is on CDT (Central Daylight Savings Time) which is -5 UTC. However, I understand that the daylight savings portion is ignored, which makes it -6 UTC. This is not really important as long as the sidereal time is calculated correctly given UTC and Longitude.
So here's a sample of what I'm seeing in the logs:
For time zone:
11:17:50.082 GetLocalTimeZone (UTC-06:00) Central Time (US & Canada)
11:17:50.082 SyncTimeAndLocationToMoun Snyc -06:00 to the mount
11:17:50.082 --> :SG+06:00#
11:18:56.622 UTCDate Get Local time: 10:18:57
11:18:56.622 --> :GG#
11:18:56.637 <-- +06:00#
11:18:56.637 UTCDate Get TimeZone: -06:00
And for longitude:
11:17:50.220 SyncTimeAndLocationToMoun Sync -098*00:00, +30*19:47 to the mount
11:17:50.220 --> :SMGE+30*19:47&+098*00:00#
11:18:56.780 SiteLongitude Get
11:18:56.780 --> :Gg#
11:18:56.781 DriverInfo ASCOM.ASIMount.Telescope, Version=6.5.15.0, Culture=neutral, PublicKeyToken=null
11:18:56.782 DriverVersion 6.5.15.0
11:18:56.793 <-- +098*00:00#
11:18:56.793 SiteLongitude -098*00:00#
So here lies my confusion - I would expect a Western Longitude of 98 degrees to be negative as it does appear to be when returned which is reflected in the logs.
Can someone please explain what is going on here? Am I just confused about how this should work?
