Trying to diagnose Asiair Pro guiding issues, can someone take a look at the detailed log I have?

[wimvb]

One thing occurred to me: during the second longer run (19 minutes), when the guide graph just wanders off, does the mount stop moving there? I'm not at my computer, so I can't check. But you should be able to calculate a tracking rate.

Rate (arcsecs/sec) = pixels/sec × pixel scale (arcsecs/pixel). If this equals or is close to 15 arcsecs/sec, it means that the mount stopped moving.

[michael8554]

From your GuideLog  22nd July:

PHD2 calculated your Guide Rate  as  RA = 5.1"/s.

This is a bit low, Cal completed in 18 steps instead of about 12, normal rates would be 7.5 or more, so try increasing the Cal Step from 1800 to say 2500.

The RA spikes that were shown in an earlier post. The first two are 4 minutes apart, which suggests a piece of grit in the worm.

The third was 2 minutes later and coincided with adjustments to Hysteresis (why ?) and a sudden dip in camera output, resulting in Star Lost messages.

Chicken or Egg ?

The guidecam output was generally low despite 3 seconds exposures - effects of the fullish moon ?

Michael

[Jay6879]

19 hours ago, JSeaman said:

Hey no problem, we've all been there. The night you accept you're going to spend the whole time solving the problem it tends to go away Just be methodical and you'll figure it

I have been methodical for weeks! And finally...finally I think I got it..

5 hours ago, wimvb said:

One thing occurred to me: during the second longer run (19 minutes), when the guide graph just wanders off, does the mount stop moving there? I'm not at my computer, so I can't check. But you should be able to calculate a tracking rate.

Rate (arcsecs/sec) = pixels/sec × pixel scale (arcsecs/pixel). If this equals or is close to 15 arcsecs/sec, it means that the mount stopped moving.

Well sir, it appears we have both come to the same assumption here about the mount turning off. Are you ready for this? I apologize for the length of this and the images but I do believe I figured it out.

Buckle up for this nonsense....

So last night I packed up the laptop and all my gear. My plan was to first let the mount run untracked and see what would come of it so I set all my gear up exactly like I do down to even the section of sky where I have been trying to point the telescope for weeks. Trying to remove as many variables as possible and keep it consistent.

So I triple polar aligned again and took my first preview image and plate solved it. Every five minutes after that I took another image and plate solved it again to compare coordinates and see the difference. Image overload incoming

Here is my first exposure taken 

I won't post every image after five minutes as it's redundant, just know that the deviation in coordinates was less than 10", well within "acceptable" periodic error and certainly not enough to cause a star to get lost and fail the guiding. Here is the next exposure just over ten minutes later, don't pay much mind to the time I took the image at roughly five minute intervals!

 

Declination has creeped up 18" and I'm honestly not sure if this is terrible or not (any insight would be helpful!) but I wasn't too bothered by it as I knew Dec was affected by polar alignment, the RA performance is what I was after.  Essentially it would jostle back and forth 9" or 10"

Something very interesting starts to happen 15 to 20 minutes since the tracking started..

It has suddenly deviated over 2m! At this point I'm like omg here we go, something is wrong with the mount. It'll need repairs or whatever. But I kept tracking and took a plate solve after another five minutes..

Oh boy..and after another five minutes here is my final test exposure and plate solve..

By this point it's obvious something catastrophic has occurred. But I didn't know what, all I knew was the tracking has now deviated well over 10m. This would certainly cause guiding to fail and the star to be lost.

 

I'll continue in the next post....

[Jay6879]

So something was wrong, what it was I'm not sure. So I go and check the mount and...nothing. There is no noise at all out of the motors. The mount has stopped! Why though? Battery voltage on the mount shows nearly full power. Balancing was good, cords weren't snagging as they'd been taken care of. I didn't understand why it stopped.

So I started searching around on the internet to see what's up, I googled "star adventurer mount suddenly stops tracking" and after pouring through a bunch of random results I come across a post asking essentially the same question. 

The answer boggled my mind. Turns out when you use Star Adventurer 2i in APP mode, whatever settings are in the app AUTOMATICALLY GET APPLIED TO THE OTHER MODES ON THE DIAL. So if you use the built in intervolemeter in the app and use say, 10 exposures at 2 minutes each (for a total runtime of 20 minutes) once the routine is finished the mount shuts off.

I had used the Star Adventurer app for the super fast slew speed in the mount controls, though I couldn't remember if I had used the intervolemeter portion after getting the Asiair Pro. Regardless, this had to be the reason why right? Right?! A wave of excitement washed over me with he fury of a thousand sun's.

I performed a factory reset on the Star Adventurer and set about tracking again.

Here is the first image and plate solve at the start of the post factory resetted Stwr Adventurer..

I won't bother posting every five minute intervals, I'll skip right to the end..

This is nearly 45 minutes of tracking! It didn't deviate beyond 10" the whole time. By this time I was feeling quite satisfied that I had possibly figured this out so I started guiding..

 

There was thin layer of high altitude happening but it was still tracking good. And here is another screenshot of the tracking around a half hour later...

It was putting up better numbers than when it started, and these numbers here were well within reason to allow 5+ minute exposures at 360mm of focal length (inhad done this before).

At this point I was burnt out and packed everything up.

So to sum up, The Star Adventurer 2i will copy all of it's settings used in the app onto the modes on the dial. For some reason. I'm not sure why. And as far as I could this "feature" isn't documented anywhere in the manual for some reason. I feel like I want to scream this from a mountain top, or have a stickied thread of something because this nonsense wasted so much time. So much frustration.

I'm sitting at about a 95% confidence level that this issue has been sorted out. I think the other 5% is residual ptsd from weeks of failure and dejection. I won't feel completely satisfied until I can image again (Sunday it looks like) and can manage to get multiple hours worth with no issue. Stay tuned though, this may not be over! (oh God I hope it is). I'll check back in here after my next proper imaging session to tell how it went.

I just wanted to thank everyone who replied here for tagging along during this saga. You've been very helpful and have filled in my gaps of knowledge. I'm going to keep trying to learn more on how to read these graphs beyond the basics, though it still feels foreign to me! I appreciate all the info that has been provided here, even on the periphery. Stuff like tips on balancing or cord management. I've learned a lot.

 

 

Edited July 24, 2021 by Jay6879

[wimvb]

As the saying goes:  ” it’s not a bug, it’s a feature.”

glad you got it solved.

[JSeaman]

Ha, what a feature - well found and congrats, fingers crossed it's plain sailing from her on out