With some notes about workflow and gear
The Wizard Nebula  
 
Date: 08/30/2024 
Telescope: Celestron 8SE
Camera: ASI2600 MC Pro
Exposures: 112 frames of 180 seconds each
Darkness Rating: Bortle7

TheWizardNebula_Celestron8Se_ASI2600MCPro_112frames_180s_small.jpg
 
I decided to capture a nebula I've done before.  Going into the Fall it seems appropriate to be thinking of Wizards.  So, I was compelled to capture The Wizard Nebula.
 
The stars, weather, and Moon aligned last night.  The sky was clear of clouds and smoke, the Moon was almost a New Moon, humidity was very low, and it was a Friday night where I did not have to get up for work the next day.  Very good conditions for a casual night of EAA.  By casual I mean, a quick setup in my yard at home.  I adjust my expectations a lot for the images I can get.  Given there is a street light directly to the South about 50ft away from the telescope.  As well as a very restricting horizon of houses and trees.  Or just the fact that I'm in the middle of a city.  With NINA running my sequence, I was even able to get to sleep from around 11pm to 5:30am.  So, it's casual astronomy.  
 
I think this near the maximum potential for my current astronomy rig.  In terms of image quality at this location.  A Celestron 8SE is more of a consumer grade or entry level telescope.  Perhaps a telescope best used for planetary observing.  I'm using it for Deep Sky Objects like nebulae and galaxies with a high-quality astronomy camera.  Along with open-source software to help make guiding corrections and post-processing of images.  Much more complicated use cases than this telescope is intended for.
 
Here is a general outline of the workflow I used last night:
 
  • Equipment setup at dusk or earlier.
    • Tripod, mount, computer, power cable, data network cable, and telescope with main and guide camera all connected correctly.
    • Make sure cable management looks good so no mishaps occur during automatic slewing later.  I like to use Velcro strips and or rubber bands for this.
  • Power on to all devices.
    • Computer, router, mount, camera.
  • Get the current GPS location from a USB device connected to computer.
    • I'm using a custom desktop application I wrote to get this GPS data and provide a link to open Stellarium at that location.
  • Open Stellarium.
    • Make sure my landscape is using one of the custom horizons created earlier with Theodolite.  Which is an iPhone app.  I wrote another custom desktop application to import the Theodolite CSV data and export it to both NINA and Stellarium file/folder formats. 
    • Make sure the current time is matching the computer's time (click the "now" button in Stellarium).
    • Locate the target or targets of interest.
  • Connect to the mount via ASCOM Device Hub.
  • Sync the mount clock to the computer's clock.
    • For my ASI AM5 mount, I go into the Advanced view and enter the GPS coordinates then click the sync from computer button to be sure the clock is aligned.
  • Initial focus using NINA.
    • Open NINA and get a quick focus on some stars visible at the home position of the telescope.  Home position at the start of a night is as close to Polaris as possible.
  • Focus the OAG (Off Access Guider) guide camera.
    • I have a Celestron OAG which is very easy to use.  I tried the ZWO OAG but found the prism to be too small for my guiding in the city.  So, rather than returning it, I scavenged it for parts to improve the Celestron OAG.  The ZWO OAG had a nice part for locking in the guide camera.  As well as some useful spacers.  Those are now parts in my Celestron OAG that improved it significantly.
  • Slew to the Zenith using NINA.
  • Take darks and flats using SharpCap.
    • I use a small drawing table light that covers the 8-inch telescope tube and turn it on at its lowest brightness.  This gives an even light for the flats.
    • Because my full frame camera is vignetted by the Celestron 8SE aperture tube, I have to crop the image I capture to a Region of Interest in SharpCap.  This then allows me to capture flats and darks in SharpCap for that region only.  I find that because of the vignetting, SharpCap has trouble averaging pixels for flats with a full frame.  Because the corners are basically completely dark.
    • I capture flats at whatever Gain and Exposure setting will allow for a good histogram.  All the other settings match what I have for regular exposures.  Camera temperature is the same, offset is the same.  For this camera, I use an offset of 50 and a temperature from -5 to -10.  Depending on the time of year.  -5 in Summer when it is hot and -10 in Fall/Winter/Spring when cooler.
    • I capture darks at the same Gain/Exposure/Camera temp/Offset that will be used for the regular exposures, the lights.  This takes the most time because I try to get at least 10 dark exposures and each is 3 seconds.
  • Get darks for the guide camera.
    • While SharpCap is creating the master dark file, I open up PHD2 and get some new darks for the guide camera.  This saves a little time.
  • Polar alignment using SharpCap.
  • Connect to all equipment in NINA.
    • Disconnect the main camera in SharpCap.
    • Connect to the mount, main camera, focuser, and guider (PHD2) in NINA.  
  • Open a sequence in NINA that I created earlier.
    • My sequences can have either one or more targets.  I followed some YouTube tutorials from Patriot Astro for that whole topic.  I look through each instruction to make sure everything is good for the night.  For example, for one target, I make sure the loop for exposures is not limited to 2 hours or something when I want to image the target all night long.  (I almost did that last night).
  • Start the sequence.
    • The sequence has steps for focusing, slew to target, stop/start the guide software during those operations, and the dreaded meridian flip.  All of that is automated.
  • "Live stack" with SharpCap.
    • Use the SharpCap folder monitor camera to (sort of) live stack the images that NINA takes.  This is not as good as using SharpCap for live stacking directly.  There is no Region of Interest feature, for example, so that won't allow applying any of the darks or flats created earlier.  But it does provide a quick way to see a stack and do a simple stretch in real time.
  • Go to bed. (Wake up if PHD2 beeps due to some tracking error).
  • Post-process the images captured the next day.
    • I use ASTAP, Siril, GraXpert, Siril again, and GIMP to process images.  Following various tutorials from YouTube.  Cuiv, The Lazy Geek and AstroDNA Observatory are my main sources for these how to guides.
That's my workflow for now.  It takes a while to get enough practice to get to this point.  I always work to make these steps better.  It seems to me that software and equipment quality in this hobby can make a difference.  So much of this would be easier and more fun if I had a dedicated outside observatory and darker skies.  Those are big changes that will take time to get to.  I'm therefore hoping to be able to work with a more professional quality telescope that aligns better with my full frame camera.  A full frame camera is less than ideal with a Celestron 8SE.  My research for a new telescope is already started.  I have to say it will be a much longer process than what went into my Celestron 8SE a few years ago.  
 
I'm looking forward to continuing with this hobby for a long time.  So, any higher quality astronomy gear that I buy will be an investment.  (Or so I tell myself).
 
Clear skies!