Question about Polar Align function - Kstars-devel Digest, Vol 238, Issue 4

[François Desvallées]

Hello:
 
We had this problem in the past with our open-source mount (TeenAstro). The design caused a wrong RA display when pointing at the pole. The Kstars alignment routine normally simulates a key press to the W or E until a certain RA value is reached.
 
Since in our case the reported RA did not change, it would keep rotating until it hit the pier.
We have since fixed this in the firmware and polar alignment works fine. 
 
Maybe you have the same problem with your mount?
 
François
 

> On 17/12/2023 08:24 CET Patrick Molenaar <pr_molenaar at hotmail.com> wrote:
>  
>  
> Hi,
>  
> I have experienced the same thing a few months ago (I haven't got to trying it again due to the bad weather in the Netherlands). I am also a big fan of KStars/EKOS. I use an RPi-4 with Rasbian and the latest KStars installed. I have a SkyWatcher HEQ5-Pro mount connected to it.
> I also noticed when using the Polar alignment function that my mount didn't stop slewing. The first time my telescope did hit the mount. Luckely it didn't damage the mount. I had to manually put the mount in zero position and realign the mount again (using 3-star alignment function on my mount). I did restart my RPi-4 if I remember correctly and then after connecting KStars again to my mount, I tried the polar alignment again. And again I noticed the the mount did not stop slewing. It continued for more then 100 degrees, until I manually stopped the motion by clicking the mount stop button in the KStars mount control window.
> I retried the polar alignment several times, going west, going east, I even tried reducing the rotation angle to 15 degrees instead of 30, but each try the mount kept rotating without stopping. Eventually I gave up for that night and didn't had a change to try it again afterwards.
>  
> In the past it had worked fine. I am now a bit reluctant to use it again when I am not near my mount to stop it. I hope there is a solution for this.
>  
> Kind regards,
>  
> Patrick
>  
> ----------------------------------------------------------------------
> 
> Message: 1
> Date: Fri, 15 Dec 2023 19:57:38 +0000
> From: Keith Hoard <klhoard at proton.me>
> To: "kstars-devel at kde.org" <kstars-devel at kde.org>
> Subject: Question about Polar Align function
> Message-ID:
>         <9P2NQV0plSFqHLn1RV9XhMf1RIBO0W05vO6O-jsdsSggtjlZ2EyZV2n6ngrdL-7F4gMpvxKkKPLtifBAgPaDb74Md1B9Bn_9EZEIzQtUxxM=@proton.me>
>        
> Content-Type: text/plain; charset="utf-8"
> 
> Last night was my first night I got out with kstars/ekos. I'm using the Stellarmate image on an Rpi-4. My mount is a HEM27EC.
> 
> When I was using the Polar Alignment function of ekos, it went thru its normal 2 RA rotations and 3 exposures. After the last one, the system seemed to halt and I didn't know if it was my VNC connection or the Rpi since I was in backyard using home wifi. The mount RA axis was rotated approximately 80 degrees westward.
> 
> I clicked "Start" button again and the PA routine began to rotate the RA axis more westward and I was able to turn off the mount power when the axis got to about 100 degrees rotation. Luckily I was right there to do that since the iOptron HEM mount will damage itself internally (and very expensively) if it is rotated past 120 degrees or so.
> 
> Of course I'm checking if there is a setting inside the mount to prevent this from happening in the future. However I am also curious if there is a setting in the Polar Alignment function that checks where the RA axis is before it begins slewing? Perhaps it may be as simple as having the PA function begin with a "Find Home" command before commencing the RA slew commands?
> 
> So far I am really liking kstars/ekos for control of my setup. I started with ASIAir, then went to NINA/Intel NUC, and am now on ekos/Rpi-4 and learning the operation of the system.
> 
> -Keith Hoard
> -klhoard at proton.me
> 
> 
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.kde.org/pipermail/kstars-devel/attachments/20231217/b6c21069/attachment-0001.htm>