Hi everybody,

Last night I ran the Polar Alignment Tool and my mount slewed into the Alt/Az base.

mount - iOptron CEM 26
server - Astroberry server with INDI lib 1.8.7
driver - iOptron v3
client - Kstars 3.5.1 on a Windows laptop

The mount started at the zero position with the counterbalance on the bottom and the Dec facing polar north. I started the Polar Alignment Tool. The first picture was solved. It slewed west, stopped, captured, and solved the second picture. It slewed to take the third picture but it did not stop. The mount head met the Alt/Az base and the RA gear kept going until I powered it off. The noise it made was terrible. Any ideas what could have caused this?

Thank you

I can't give you the answer, but maybe a couple of useful notes.

First, I *don't think* the horrible noise is damaging to the mount. I suspect that is the sound of the stepper motor skipping/stalling. I hope that is the case, anyway.

Second, the CEM25p does not have a "Park", which leads to weird and potentially hazardous behaviors with Ekos and PArk vs Zero Position. I assume it is likely that the CEM26 shares those. There are a couple of long threads here you probably want to read through (though it involves wading through many pages of not-solving the problems, there is the occasional nugget).

Here is the procedure I use *every time* I start Ekos or anything changes with the mount.
1. Use the hand controller to Clear Alignment Data (I only actually do this every once in a while, so I already lied about the "every time" thing)
2. Use the HC to set Zero Position (unless it already reads "Zero Position")
3. In Indi Manager "Set current position as Home" (I've never used goto Home, but as long as I'm setting things it seems a good idea)
4. In Ekos Mount Tab click "Clear Parking Data"
5. Back to Indi, go to the Site Management tab. In the Parking line hit Clear (that is redundant, but I find it reassuring to be told that there is nothing to clear)
6. Same line, click "Current" (the dot should change from red to green), then Write Data

As long as I do that and nothing happens to alter the mount's sense of where it is pointing, "Park" in Ekos works correctly and does not send the mount off to who-knows-where. This might not be the answer to your Polar Align 2nd Rotation question, but it's something every CEM25p / CEM26 Ekos user needs to know)

That's correct. Ioptron confirmed this.

The CEM 26 does have a parking function that defaults to pointing at the horizon on the west side of the mount. This was the same direction my polar align routine was slewing.
After some brainstorming, I believe that I unlocked the RA and manually slewed to a zero position sometime prior to running the Polar Align routine. EKOS was set to autopark after completing the Polar Align. So, I must have been mistaken that the runaway happened between the 2nd and 3rd capture. The routine must have completed, received a park command from EKOS and slewed further west into itself. I have now unchecked "autopark" after completing the Polar Align routine, and I've set the parking position to the zero position.

Do you know what data this clears? Is it parking info in the hand controller?

Thank you for your help!