Pinwheel Galaxy (M101) and Equipment Tuning

My objectives for this session were to have another trial imaging run prior to doing a full dress rehearsal, which I will defer until after I resolve the RDT issue. My target for this session was imaging M101 in luminance only. I will combine this with the RGB data that I captured the night before.

The setup was G11, NP101is, ZWO ASI6200, which were all unperturbed since the night before. Because they were unperturbed, I decided to skip polar alignment, initial manual focus, and calibration, and went straight to imaging when it got dark enough.

The conditions at 2100 when I powered up the equipment were 77F and 61F for temp and dew point, respectively. There was an occasional light breeze. Since I was running on wall current, I left the dew heater on just to have one less thing to worry about. Astrospheric said that transparency is average or better and seeing is above average all night.

The only outside part of my plan was to power up the mount and minicomputer. Once inside I was to make an RDT connection to the minicomputer and start up NINA and PHD2. After connecting cameras, focuser, filter wheel and mount to NINA and PHD2, I then set up an imaging sequence in NINA to slew to the target, plate solve to center the target, do an initial autofocus run, start guiding, start imaging (L, 130 x 120s), and autofocus again after every 20 images. If needed, I could have added an automatic meridian flip to the sequence that would have executed as the target crossed the meridian.

It was sufficiently dark at 2150 to begin imaging, so I initiated the sequence. The first slew to the target failed because I did not have the Ra clutch tight enough. This was the same problem that I had on the Dec axis the night before. There seems to be a thin line between getting the clutch tight enough to function properly and getting it too tight, which causes stiction. I think that I now have a good feel for how much to tighten the clutches.

I adjusted the clutch, reset the mount to CWD, restarted the mount and re-initiated the NINA imaging sequence at 2215. The sequence performed autonomously and flawlessly until I ended it at around 0400. That was perhaps my coolest astronomical feat to date. I monitored data quality and progress until about 2330, at which time I sacked out. I woke up at 0330 and found that the sequence was still operating flawlessly and data quality was still reasonable, even though the target had descended to 40-ish degrees elevation.

I let the sequence run until 0400, and then shut it down. The temperature and dew point were 66.6F and 66.4F, respectively. The optics were dry, but there was dew on metal surfaces, which was to be expected since the temp and dew point were so close.

Because of the RDT connection issue that I will need to discuss yet again, I did not even attempt to capture Flats.

All was not Guns and Roses (sic) for this session. The RDT kept dropping, usually after being connected for just 60s. This was quite annoying, but at least the imaging session on the mini-computer was not interrupted, and each time the connection was quickly and automatically re-established each time. While the sequence was running in the background I did some research and troubleshooting, but found no resolution. Looks like less than good astronomy weather for a couple of days, so getting this squared away will be my first priority.

My thoughts about how OneDrive should work at home vs. in the field, and I think that it was doing this at one time, was that I would make the RDT connection via home wifi, and saved image files would be synched to OneDrive in near real time. This was very convenient, because I could access image files for processing without powering up the minicomputer and enduring a lengthy download period before I could begin processing  the next day. In the field, I would be making the RDT connection via the nano router wifi. The mini computer would simply not be able to synch OneDrive files because OneDrive is not available over that wifi network. For some reason this isn’t working now. I will gladly give up the inconvenience of not having images waiting the next day on OneDrive if RDT would work like it is supposed to.

My current suspect is that OneDrive is knocking my connection out when NINA or PHD writes to their various log files. Maybe even synching an image to OneDrive knocks it off. I want to look at firewall settings, number of RDT users allowed, and even configuring the way that I will operate in the field.

My only other post session priority will be to process the images from the last two nights. I think that I have eight or nine hours of integration time on this target from the last two nights. I will lightly process and post a single L image later today.

Here’s a thought that I need to figure out what to do with. Being able to power up unperturbed equipment, start up software, connect devices, and initiate an automated imaging session makes my knees weak. To do this on a regular basis, I would need an observatory. One approach would be to set it up with the G11 and have either the Meade or TeleVue on the mount. After tuning the GM8, I could use it at dark locations like the farm.

All in all this was a successful session that I enjoyed very much. There have been a lot of “pieces” that have had to come together to make this possible, and it was gratifying to see equipment, software, and process come together to produce the result that I want. The RDT didn’t take too much away from that.

M 101_2022-05-29_21-53-50_LIGHT_R__480.00s_100db_1x1_-5.00F_offset=_0000

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