Re: Ap900gto parking issue at end of the session

Dale Ghent

The ASTAP plate solve is then failing because the RA and Dec that it is being hinted with, which is taken from what the ASCOM driver reports, is outside the search radius of ASTAP when it compares stars in the frame. So then it fails and the blind solver runs, which is an all-sky solve that will take longer because it's searching the entire sky.

So it's obvious that the ASCOM driver thinks it's pointing in different places in the sky than you really are, and I think it comes down to how you're parking and unpoarking the mount, which seems like it can be error-prone if you skip a step.

When you unpark the mount, you are essentially telling the mount that its axes are oriented in the configuration that defines that park position. So if your mount stops working during the night due to drained batteries, then you unclutch the axes and manually move it to the Park 3 position, the mount will move like a drunken sailor if you then power things back on and forget to tell the mount to unpark from Park 3.

The Set As Park button in NINA may be exacerbating this issue and I would advise against using it if you really have no need to. What that does is tell the ASCOM driver: "Whatever position you think you're at now, this is your new park position." If the mount's notion of its orientation is already messed up, or gets messed up later, this can further that problem.

Since it *appears* that you're imaging from the comfortable trappings of a residential backyard, I would suggest that you get a good 12VDC power supply and use that to juice your setup. After all, it's better to use mains power if it's available instead of battery and you'll avoid the battery draining out in the night, especially in the cold season where it'll conk out earlier than you're expecting. This way you don't subject the gear to low voltages and your sequence can properly end and park your mount at the desired position for you. It's just better. Keep the battery for a power outage or if you take your rig to a dark site.

On Jan 22, 2023, at 22:11, palamrinder via <palamrinder@...> wrote:

Hi Dale. My east side have some light pollution from nearby homes and west side has some trees that's why i went closer to Zenith. But I can try something in the vicinity.

Plate solving is only an issue when mount is not calibrated (manually as I figured out) properly. If It knows it is parked right, plate solving never fails unless there are clouds or other typical issues. So I believe there is conflict happening between mount's location and what NINA calculates which causes the plate solving issue.

Yesterday before I started the sequence I pressed the "set as park" button on NINA after setting the mount to park 3 position (see the process I follow for manually setting it to park 3). Some clouds showed up and I decided to end the sequence earlier (before meridian flip). So I pressed the park button on NINA and mount came back correctly to Park 3 position. I wonder if it would have done the same on it's own as well. I will try to check that tonight and let you know tomorrow. I'm hoping the mount will park in right location unless it loses the sync post meridian flip.

Thanks for sharing the manual setting process. Since I have to move the mount to park 3 in morning and my batteries are fully discharged so I move it manually after loosening the RA and Dec screws and in the evening follow this process before anything else.
1. Turn on camera, focuser, fw and telescope in NINA. This opens up the mount ASCOM window and automatically unparks the mount.

2. Expand the ASCOM window and select Park at current location

3. Then I select unpark from Park 3 position

4. This is followed by Park to Park 3 (mount does not move)

5. And finally unpark from current position.

This always syncs the mount and everything works flawlessly (slewing to right location, plate solving sequence etc) except for mount not ending up in Park 3 after sequence ends.

I didn't have to follow this process today as NINA correctly parked it at Park 3 last night so will see if it goes to right location tomorrow morning.

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