My objective last night was to work with the TV/GM8. I chose to work with the GM8 because I want that to be performing well when the G11 goes back to the factory.

My planned targets were Jupiter and moons with the ASI290, and Albiero with the ASI6200. I was pretty sure at  the outset that I would come to regret changing cameras and chasing two targets.

I was out for about two hours from 2000 to 2200. I did not assess seeing, but transparency seemed pretty good. Although a little chilly, the evening was pretty dry. Surface winds were still.

Set up went well with hardly any fumbling around. I think that my frequent visits to the telescope over the last several weeks has paid off, even if my work was with a completely different setup.

I powered up at 2000 and went straight to Jupiter without polar or star alignment, and was able to see it on the display without further adjustment. This task is much easier at the shorter focal length. Even with the shorter focal length and no PowerMate, the moons were quite spread out on both sides of the planet taking up most of the display width. I was able to select a generous ROI that covered about 25% of the available display. I was not happy with Jupiter’s resolution, but I shot it anyway in LRGB, 90 seconds per filter.

I moved on right away. After swapping cameras I rebalanced and did a did a polar alignment with the scope and with the PoleMaster. Next was a slew to Vega for a star alignment and initial focus. I did not bother to assess seeing since I was working at 540 mm of focal length.

With this done, I powered up the minicomputer and was able to connect the laptop to it the first time. I brought up NINA, connected to the camera and the filter wheel without issue. I manually focused using the NINA display and the Bahtinov mask. And then I attempted to slew to Alberio via Stellarium, but the scope would not slew. The computer was connected to the mount. I could see the scope icon on the Stellarium display, and it would even move when I manually slewed via the hand controller. I put the scope on Alberio by watching the icon move on the display. I elected to not troubleshoot this further since this problem can be addressed in the daytime.

I opened PHD2 and connected the guide camera and mount without issue. I noted that I was getting 2” RMS guiding, but accepted that as good enough for my work tonight. I loaded a LRGB sequence in NINA, and settled on 21 L at 60s, and 7 each of RGB at 75s each. After starting the sequence I realized that the laptop was not physically connected to anything (which is a big change from the way I do planetary imaging), so I went inside to monitor.

Upon arriving inside, I noticed that I was getting severely elongated stars. I checked PHD2 and it was still guiding at 2” RMS. The guide star profile had a flat top rather than a peak, so I forced another guide star selection, and that made some improvement. I noted that the scatter graph had a linear pattern that started just outside of the 2” circle and just above the x axis, descending through the  center, and exiting the graph just below the x axis. This tells me that I was having issues on just one mount axis. I did not investigate further. I shut down at the end of the sequence.

I am glad to have this first night with the GM8/mini computer. I do regret spending the time on Jupiter, and having spend the time to re-camera and re-balance. This time would have been much better spent working out the issues that I encountered.

It feels like I have at least made it to square two. Square three, I think, is to work on guiding with the same dedication that I did on the G11. That means reading the literature, to include the best practices document, and I must be prepared to dedicate a night to assessing and adjusting to get good guiding performance. I also need to accept that I am just going to be working on one side of the sky, and to be sure go with a east-heavy bias. Next I need to get plate solving and auto focus working correctly, and then start working on exposure.

It looks like the next couple of nights will be clear enough for the work that I need to do, so I am glad that I have gotten started. I have a lot of grunt work to do before I start imaging in earnest.

My work today will consist of carefully rebalancing for working in the eastern (my darkest) hemisphere by making the counterweight side slightly heavier, getting slews from Stellarium to work, cleaning optics and reading about PHD best practices. I want to visit my PHD logs so see what I can glean from my guiding issues, but I don’t want to delve to deeply into that until I know that I am paying careful attention to the basics.

Jupiter with Satellites - 2021-09-30 00:19 UTC
Jupiter and Galilean Satellites

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