Pointing

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Sep 6, 2018, 18:24
David Bennett

Tracking Stopped After Imaging / Plate Solving / Pointing

I am testing ACP with MaximDL - both are new installations. I have a Losmandy GM8-11 with Gemini-2. I use Polemaster and my polar alignment is pretty good. When i slew to a target with the hand controller the target is within the FOV of the camera. I start ACP and connect to the instruments no problem. I am having some trouble with tracking but that is happening within MaximDL as well so I need to sort that out separately. I have no idea why though - seems to be set up correctly based on the forum responses i have searched for.

The main issue is the following: I submit a request for a single target and single filter. ACP eventually finds target but only after all sky solving. I don't know why this has to take so long. Then, after a full sky plate solve the auto focus begins and ends (FocusMax) and then imaging begins. The tracking fails but the imaging starts anyway. When the image has been taken, the last ACP message is that "tracking has been stopped". When i re-submit the target via ACP, the scopes starts slewing again. Two nights in a row i had to run out and turn off the mount to rescue my scope from hitting the mount.

I know that ACP is using the Gemini controller, not EQMOD. I could be wrong but i don't think EQMOD supports Losmandy mounts.

Why does plate solve take so long and how does the mount get so lost. Since tracking has stopped does ACP assume that i have parked the mount?

Any help is greatly appreciated. Thanks in advance.

Dave Bennett
Sep 6, 2018, 22:36
Bob Denny

Look at the log and note the pointing error after the all-sky solve/sync. All-sky can take a veryu long time, up to 10 minutes, at Astrometry.net (ACP/PinPoint uses this service). If you want to call 480 396 9700 tomorrow 8-5 mountain time I'll chat with you. Meanwhile you might locate the log in My Documents\ACP Astronomy\logs and attach it to a reply <- link to attaching instructions.
Sep 7, 2018, 22:58
David Bennett

Things did go smoother last night. I did a test image first and after the image was collected, ACP did stop guiding and left the scope pointed toward the target. I parked the scope via the ACP pulldown menu. I then set up another image and this time it went to the target. During the first imaging task the pointing error was 80.1 arcmin. This doesn't seem like a lot but it had to do a full sky plate solve. The second imaging task solved quickly and guiding did work last night. I got it working in Maxim first but i have to admit i didn't change a single thing from the night before.

A couple of qestions:

Why doesn't ACP park the scope and/or stop tracking - and why would it not know where it's pointing if i submit the target again? This has me concerned.

Does ACP honor the mount limits i have set via the Gemini hand controller?

Can I use the ACP Planner without Starry Night or The Sky?

How can i see the web interface from my iPhone so i can monitor the run. i'd like to see how this works.

Thank you...

dave
Sep 8, 2018, 00:18
Bob Denny

2 Attachment(s)

Quote:

Why doesn't ACP park the scope and/or stop tracking

If you add a #shutdown directive to your plan it will park it. It always stops tracking when it's not doing anything. Otherwise it leaves your scope ready for further work.

Quote:

Why would it not know where it's pointing if i submit the target again?

ACP knows exactly where the object is: at the coordinates in your observing plan. However, when it tells your scope to slew to the target, your scope is missing it. 80 minutes is a large error. That's why it's all-sky solving. Even after it is synced, is it doing this? Try turning OFF the ACP pointing corrector.

Quote:

Does ACP honor the mount limits i have set via the Gemini hand controller?

ACP has no idea about all of the limits in the controller. However it does have settings for flipping and for minimum elevation above the horizon. It will honor them but gain it has no clue about the myriad of flip settings in the Gemini. Better people than I have tried to get things right on the Gemini and I confess to have been buffaloed by it. I'm not saying it's impossible, just that it is complicated and confusion prone. Mainly you have to set it to flip at the meridian (remember, a scope never flips while it is tracking, only when it is slewed!)

Attachment 10177

Quote:

Can I use the ACP Planner without Starry Night or The Sky?

Yes. Right click to add targets.

Quote:

How can i see the web interface from my iPhone so i can monitor the run. i'd like to see how this works.

Big question:

Attachment 10178