Ghost slewing with Skywatcher HEQ5 PRO

[Chiefsmith]

Is there a problem with my SkyWatcher HEQ 5 PRO mount. On 26 February 2024 I started a session for M45. After eight shots the mount just slewed away from the target and I had no idea where it slewed to.

The equipment I was using 26 February 2024:

SkyWatcher HEQ 5 PRO mount
Sony a6600 camera with the Sony 2x tele converter
Askar 200 Astro Lens

Software:

Astrophotography Tool (APT) v4.42, Green Swamp Server (GSS), and Stellarium.

THE NEXT NIGHT, 27 FEBRUARY 2024, I HAD THE SAME ISSUE! After 12 shots, I went outside to check everything. As I was walking to the mount it started slewing away from the target (M45). I just watched it until it was done slewing.

Everything, equipment and software, was the same as on 26 February 2024 except that I had installed APT v4.43.

This is pointing to M45 and where it was supposed to be pointing.

The mount just started slewing away from M45 and stopped slewing at this point.

Does anyone have any idea why this is happening and what I can do about it? Is there, perhaps, a bad board in the mount head that needs to be replaced?

[Lady Fraktor]

How is your power supply?

Have you checked your slew limits?

[Gordon]

I have a SkyWatcher EQ5 mount and have successfully ran it using EQMOD and cartes du ciel for years. I tried Green Swamp Server in place of EQMOD and had similar results to what you are seeing. It very could be 'user error' but, Here's my reasons for using what I do.

1. EQMOD, been around for years, very reliable. It does take a bit of playing to get everything set but once it is, it works. https://eq-mod.sourceforge.net/

2. Cartes Du Ciel, again been around for years. Not as fancy as Stellarium for sure but it does play nice with eqmod and doesn't use near the computer resources. With that said, I don't feel that your symptoms are from Stellarium.

APT has quite a reputation so if you are familiar with it I would say to stay with it.

Best of luck and please keep us in the loop with what's going on.

[Chiefsmith]

I am still very much in the learning stage - at least that is what I think. I received my Skywatcher mount in June 2022. The weather from that time to now has been so terribly bad that in the 20 months that I have had this mount and learning Astrophotography for the first time, there has been maybe, and this is a very generous maybe, five months of reasonably clear skies. This is my retirement hobby - my wife has taken up painting for her retirement hobby!

My HEQ 5 PRO came with a power supply so I do not think that is the problem. About four/five/six months after receiving my Skywatcher mount I moved away from the Sky-Watcher Synscan and tried EQMOD. There were so many issues with that not working, and after reading recommendations for GSS, I tried GSS and all my problems immediately went away.

I really like the way GSS works; but, if it turns out that GSS is the problem and EQMOD the solution, then I should probably really work on making EQMOD work. So, according to the weatherman, we will not have clear skies for weeks if not months into the summer months. That means that I will have time, during the daylight hours, to download and install EQMOD and test that against GSS by shooting my M45 light frame session. This is really frustrating because I had two nights of party cloudy skies that gave me, in total, about 4-hours of clear enough skies to work on M45 and only then have these slewing issues.

Or, it could be that my mount is defective! Since I need all the help I can get, I also referred this situation to the EU distributor and the store that I purchased it from. They have not yet responded.

[Gordon]

I usually setup my mount and scope inside during the day to test things out. With slewing you can get a pretty good idea it things are moving in the right direction. You can also capture dark frames at the same time to test if the mount moves after a few frames. If you like GSS, by all means stick with it and see if it still acts the same.

[Chiefsmith]

I had three nights of absolutely clear skies in spite of the weatherman predicting cloudy skies. Prior to the last three nights I tried EQMOD and again uninstalled it. It is just too much trouble for me to try to master. Now, during the first of the three nights I had decided to do the session without Stellarium. Worked just fine. I had no weird slewing issues and my HEQ 5 PRO stayed with M45 the entire shooting time. At the end of the session I discovered that I had forgotten to engage the Copy, Go To, and Sync commands of GSS. I did the same thing the next two nights. I did not boot up Stellarium and I started GSS but did not do anything with the three commands that I forgot on the first night. Everything tracked perfectly so this is what I will continue to do - at least as long as it works.

As far as APT slewing to M45, that just would not work until . . .. I got so frustrated that I unclogged (? is that the right word when you release the two black levers on the HEQ5 so the head moves freely ?) the mount head so I could position it by hand. Jupiter is the biggest and brightest object in my part of the sky so I manually moved the mount head so that Jupiter was in the camera screen and visible in APT LiveView. Using the GSS controller I put Jupiter in the exact center of the screen. With Jupiter in the center of the screen I used the APT GoTo command for M45, the mount slewed right it and put those stars in the center of the screen. After the M45 session was over I clicked on M42 in APT, hit the GoTo button, and watched as it slewed right to M42 - although M42 was just a little below the horizontal center line it was centered on the vertical. I have to shoot between my roof and that of my neighbor so I only have a couple of hours before his roof interferres with a shooting session.

[Gordon]

Well it sounds like you are making progress. You do have to experiment to find the tools that work for you. Glad to see the improvement!