Exploring the Suffolk Virginia Night Sky – Astronomy, Astrophotography, Telescopes, EAA – Planets and Stars and Nebula and Galaxies – Looking, Learning, Sharing… Let's see what we can see…
Nice clear night. Still doing a lot of tinkering and testing with the AT66ED setup. The plan was to work on getting the focus configuration dialed in and I was able to do that. Then I decided to gather a couple hours on NGC 6888, the Crescent Nebula, in Cygnus. I started capturing light from NGC 6888 a little after 9 PM and collected 2 hours of data from it. The session was recorded to my Lightbucket account.
I did a lot of testing with the Gemini Focuser and NINA settings to get consistently good focus and decent focus curves. Trying different settings for focus steps, exposure time, and backlash. The amount of backlash was the primary issue, I ended up having to set the overshoot to 400 steps to compensate. Once I had that dialed in, I was able to get the autofocus to work consistently. I’ll do a post on my NINA Autofocus configuration with the Gemini Automatic Star Focuser on the AT66ED soon.
On thing that I have working very well is guiding with the OSSAG and the SVBONY SV165 30mm guide scope. I did not do a polar alignment, I had not moved the scope since the last session so I just went with it. My total RMS was around 0.5 or lower for the entire session.
NINA executed a meridian flip during the sequence. This worked exactly as expected: flipping the mount, recentering on NGC 6888, running the autofocus, resuming guiding, and then restarting the capture. Nice!
Primary (Imaging)
Secondary (Guiding)
Scope: Astro-Tech AT66ED (400mm – F/6)
Reducer/Flattener: None
Filter: None
Camera: ZWO ASI294 MC Pro, Cooled to -10 C
Focuser: Gemini Autostar Focuser
Mount: Sky Watcher EQ6-R Pro
NGC 6888, the Crescent Nebula, is an emission nebula in the constellation of Cygnus. The nebula is about 5000 light-years from Earth.
This is a stack of 40 x 180 second (2 hours) exposures at 121 gain, 30 offset, and bin 2×2. Stacked and calibrated (darks) with Sirilic. Cropped, background extracted, and denoised with GraXpert AI. Then stretched and tweaked in Siril.
A bit of details along the edge and a hint of the stringy cloud filaments that fill this nebula. There is a lot of glowing gaseous clouds through out the field of view. The Soap Bubble Nebula is in there somewhere but will require a lot more time to see. This area and target would be a great to try out the new SVBONY SV204 Multi-Narrowband filter, but I am still waiting on an M48-M42 adapter so I can add the ZWO Filter Drawer to the image train on the AT66ED setup.
Will be traveling for a bit so going to secure the scope, probably won’t get another session in for a week or so.
