Process Tuning, Monkey Head Star Data, and Moon

My objectives for this session were twofold. First, walk through my new session startup workflow (focus, capture flats, polar align, and calibrate/GA run sequence) to see how well it flows in practice, and to see if I can complete these activities before end of astronomical twilight. The second is to capture some Monkey Head star data for an initial exploration of a processing technique that I wish to try.

The setup was G11/NP101/ASI6200 (90 degrees). I want to start annotating my camera rotation angle for the new technique that I will be telling you about.

Conditions were not too bad. Temps were in the high 20s, RH was 48%, and there was an occasional slight breeze. Astrospheric forecasts were Cloud Cover 0%, Transparency BA, and Seeing BA.

The session startup workflow went extremely well. One of the questions that I wanted to answer was: would doing focusing and flats capture ahead of polar alignment in the startup sequence delay polar alignment. Before this change, polar alignment was first in the session start up, and it was accomplsihed 35 – 40 minutes after sunset. This left plenty of time to complete PHD2 calibration before the end of astronomical twilight.

Sunset was at 1733, and my goal was to complete the session startup activities before End of Astronomical Twilight at 1904 so that I could demonstrate that I would not lose any imaging time to session startup activities . I was surprised to be able to see Polaris and Bahtinov mask spikes at 1745, just 18 minutes after sunset. Focus was complete at 1750, at which time I removed the mask and installed the flats panel. The NINA Flats Wizard got me through RG and B Flats by 1801. After removing the flats panel, I reconfigured for polar alignment. I was barely able to see Polaris, but I had to wait two or three minutes to see the other stars that were needed to polar align. In short, there was no time penalty for focusing and taking flats before polar alignment. I finished polar alignment at 1810, slewed to 0,0, and initiated calibration. Calibration completed without error, so I stepped into a GA run at 1811. I forgot to uncheck Measure Backlash, so the GA run took an extra minute. I accepted the GA recommendations and the scope was guiding at 1825, which was 39 minutes before End of Astronomical twilight.

At 1904 I initiated the star capture sequence. NINA slewed to the target, plate solved, centered on the target, autofocused, and initiated the capture sequence. The capture sequence was 35 frames in RGB at 20s each channel, which executed nominally by 2015.

As a bonus round, I swapped the DSO imaging train for the planetary train with the ASI178 on the back to image the nearly full moon that had caught my eye earlier. Switchover was only difficult because of the cold. Temperature was about 27 degrees. I also had a brief fumble in that I forgot to flip the mirror. How quickly we forget! The lunar diameter barely fit within the height of the sensor frame when attached to the NP101, so I elected to capture in two panels that I will stitch together in processing.

Session was over and power shut down at 2050.

The Monkey Head Nebula (N2174) Star Field - 2023-02-04
Monkey Head Nebula Star Field (Nebula removed from image)
The Moon - 2023-02-05 01:47 UTC
The Moon

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