LX200 GPS does not work with time settings

[Photo-Stan]

I have an 8" LX200 GPS. in general, it works well with APT but there are problems with time/location settings.
For starters, there seems to be a problem with Autostar II.
We are in DST, Daylight Savings Time. When I enable DST in Autostar II, the local time shown after GPS sync is incorrect, 1 hour ahead of the actual time.
The local time is correct only when DST is disabled.
There is more. If DST is enabled and I sync on a star, its RA is reduced by 1 hour.
For instance, RA of Altair (19h50m) is reduced to 18h50m. This does not happen when DST is disabled.
The same problem happens when APT connects to the mount.
Under 'Location' tab in settings, if 'Export coordinates to ASCOM... Export PC time to ASCOM' is enabled, then the RA of an object sync'ed with Autostar II is reduced by 4 hours (as displayed by Autostar II),.
When APT connects to the mount, there is a message at the bottom: Cannot set Latitude. Exception occurred. Cannot set Longitude. Exception occurred.

The only way to eliminate these problems is to change these settings:
1. Disable DST in Autostar II.
2. Disable (uncheck) 'Export coordinates to ASCOM... Export PC time to ASCOM'.

Then you sync the mount using Autostar II and when APT is started it does not change RA values.

[Yoddha]

Hi Stanley,

Thank you very much for sharing the solution!

[jhart]

I do not know about the LX200GPS, but the LX200 Classic uses a unique way to enter longitude. It uses only positive longitude degrees counting west from 0° all the way around the world back to Greenwich. There is no + or - and no E or W. Syncing location data among the LX200, APT, Stellarium, SGP, NINA, etc. can be a problem. Unlike the LX200, they want longitude in + (east of Greenwich) or - (west of Greenwich), or with an E or W added. (Offset from GMT can also have a different + or -). Syncing location data across platforms with differing longitude entries could throw and exception or create really funky results (such as the LX200 reading "-" as a "2" and tacking that "2" onto its internal determination of longitude and deciding that instead of being in the eastern part of the US, it is somewhere in the Himalayan mountains ).

[Yoddha]

Hi Jeff,

Interesting info... How the driver reports the LX200GPS? Maybe is possible to send 360-West_Long...

[jhart]

Hi Ivo,

I have not looked at the old logs to see how the longitude was reported on my LX200, which is a Classic instead of a GPS. As I remember, I tried different import and export options under Synchronize the selected location in the APT Location settings. Problems started happening in GoTo with the telescope controller and sometimes with PointCraft plate solving. I don't remember exactly, but once I checked the site data for the telescope and it's longitude was changed to 297° instead of 97°. Another time I checked in APT and its longitude was changed to 97° E instead of W.

I assume that if I make sure I have entered the same latitude and longitude in my ASCOM drivers and telescope as I enter in APT and check Use only in APT under the Synchronize options, I will be ok?

Jeff

[Yoddha]

Hi Jeff,

If you select the option "Use only in APT" then the coordinates in the telescope and the driver will not be altered and will not be read. So you have to remember to update the location in order Darkness Clock to be accurate.

[jhart]

Hi Ivo,

If the site lat and long are correct in the APT Location tab and the “Use only in APT” option is selected, will APT still be able to control the mount and sync celestial coordinates with the mount and Stellarium?

Thanks,
Jeff

[Yoddha]

Hi Jeff,

The calculations that need site coordinates are these in the Darkness clock - Moon/Sun rising/setting times and the twilights. The Sync and solving are not directly bound to the site. They are needed for the scope/Stellarium. It calculates the expected position then with the Sync you define what correction is need - making it visually or via solving