My last two imaging sessions, something went awry. First time I thought it was me. Second time, it might still be me, yet I thought I would reach out.
Symptom: After polar aligning and star aligning my CGEM via hand controlller and such, Ekos/INDI would not slew my mount as it normally would. I am using the Celestron GPS driver for my CGEM-DX.
The hand controller would skew the mount fine.
Picking any object via Kstars, or the mount controls to search and goto, would not skew the mount at all.
Hitting the unpark button would report mount is already unparked.
The solution: hit the park button. This moved the mount to a position. Once it parked, I then hit the unpark button and the mount could skew once more. I also found I had to toggle tracking on and off after this as well.
Nothing has changed in INDI or Ekos regarding this, so it is odd. If you enable verbose logging in the Celestron driver, you see see commands being sent to the mount when you slew?
Perhaps this is the issue, as until this summer I was not confident enough to use the Park/Unpark commands, and now I am.
In the celestron_gps driver ReadScopeStatus() method the Park state is saved.
I setup and take down each night. Once the scope is setup (assembled, polar aligned, star aligned, focused) Ekos/RPI3 is connected and started.
Since the park command may or may not have been used in Ekos from previous session, in the case it was Ekos starts up assuming my scope is parked - it is not. The states are out of sync.
The only work around is some combination Unpark/Park/Unpark/Trackmode-on-off/Slew/stop needs to be run - which is out of sync with the current alignment - and actual sends the scope into a different position from the default park position depending on the star/target I last used from the HC.
Is there a away to "initialize/reset" the park position status?
Without it it means I should not be using park and should be using a script at the end of my session to turn tracking off.
EDIT: I just noticed that the status of the Park/Unpark between Ekos and INDI may not be in sync because of this too. Ekos Mount Tab had Park enabled for clicking, and Unpark disabled; INDI Park command was the reverse.
When Celestron parks, it store parking position and state in ~/.indi/ParkData.xml which is read when the driver starts to set the status of Park/Unpark.
The position saved is Az/Alt, so on UnPark(), it is read from ParkData, converted to current RA/DE and then a SYNC is issued with these coordinates. If there is a better method that works for all celestron range of mounts, let me know.
This problem was pointed out earlier in the SYNSCAN - AZ mount, DSC driver, but because the home position definition was not initially set when the driver was loaded.
The park and unpack buttons will not work unless you first define the home position and calculate it.
This also applies to sync buttons.
Once this is overcome, INDI allows for parking without alignment and hand mounts on any mount.
Especially if you leave the default as parked, since there is a possibility of trouble, we hope that by taking home position as the origin by default, it will automatically be set to a safe position.