Thursday 8/20/2020 promised to be clear night with average seeing according to Clearsky Charts and NOAA. I decided to head for the Harvard library darksite with the goal of imaging the Crescent, the Eastern and Western Veil nebulae using the Starizona Night Owl gambling on 120s sub frames at f/4. That proved a mistake. The results were under exposed and noisy. I won't bother posting the images here. In the future I will try imaging with 300s sub frames that yielded better results at a higher f/6.4 focal ratio in the past.
Fortunately, I also imaged Comet Neowise, M8, M16, M17, M20 and M13 on the same night. Sub frames were acquired with 30s exposures at a gain of 120. The images appear below. The images are pretty okay but could be better. The auto-guider was quite erratic along the RA axis resulting in elongated stars. With the waxing moon I will focus on debugging this issue locally starting with running the PHD2 setup wizard.
On a different note flat frames captured during twilight were at the wrong focus making them useless. I decided to keep the optical assembly together and collect a set of flat frames at home next day. The first set, taken from a lamp illuminated wall looked good but yielded ugly images marred with gradients. At first I assumed the problem was camera settings and light pollution. On a whim I tried using a white jpeg image on my LED HDTV screen as a flat frame target. It worked resulting in the images below. 😊
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Comet C/2020 F3 Neowise
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M8 (Lagoon Nebula)
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M16 (Eagle Nebula)
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M17 (Omega Nebula)
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M13 (Hercules Cluster)
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M20 (Trifid Nebula)
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