My First Wizard Nebula: A Journey into Astrophotography Challenges

As a newcomer to the captivating world of astrophotography, I recently set my sights on capturing the mystical NGC 7380, affectionately known as the Wizard Nebula. This marks my maiden voyage with this celestial wonder, and while I'm quite pleased with the initial results, the journey has also highlighted some areas for improvement, particularly with my star rendering.

The Pursuit of Pinpoint Stars

One of the biggest hurdles I'm currently facing is achieving those crisp, pinpoint stars that truly make deep-sky images sing. Lately, I've been wrestling with various equipment issues, including sensor tilt and back focus, which undoubtedly contribute to star elongation. Any seasoned astrophotographers out there with insights into resolving these common problems, I'm all ears! Your guidance on achieving better star quality would be immensely appreciated.

This hobby has only been a few months in the making for me, and it's a steep learning curve, but an incredibly rewarding one. Following my recent foray into the Pac-Man Nebula, my next target is the West Veil Nebula. However, due to its brief visibility behind my house, I'm limited to integrations of roughly two hours for that endeavor.

My Gear Setup

Here's a look at the equipment that brought this image to life:

• Camera: ASI585MC Pro with an L-eXtreme dual-band filter
• Telescope: Explore Scientific ED80
• Guide Camera: ASI120MM Mini
• Mount: Sky Watcher HEQ5 Pro
• Control System: ASIAIR Plus

My capture settings were as follows:

• Gain: 200
• Exposure: 180 seconds
• Light Frames: 105 frames, totaling 5 hours and 15 minutes of integration time.
• Sky Conditions: Bortle 5/6 skies

Processing Workflow and Challenges

The processing of this image involved several stages. For stacking, I opted for DeepSkyStacker. I encountered an issue where Siril was overexposing my brighter stars during stacking, so DSS proved to be the more suitable tool for this particular capture. Unfortunately, I had some trouble with my 50 dark frames, preventing me from stacking them. I plan to revisit this and re-process the image once I resolve the dark frame issue.

My primary processing was done in Siril. I manually stretched the data and then utilized the StarNet star removal feature to isolate and stretch the nebula itself. For noise reduction, I turned to GraXpert, and the final touches were applied in Photoshop. I had initially hoped to experiment with a specific dual-band processing workflow in Siril, but my attempts to split the Ha and OII wavelengths using the available scripts consistently resulted in errors. For now, that particular workflow remains on hold.

My initial description of the star removal process might have been a bit unclear. To clarify, I used StarNet before stretching the nebula. I extracted the stars, leaving a starless nebula, and then stretched the nebula alone. After that, I combined the starless nebula with the star mask created by StarNet, performing some additional stretching on the stars within the StarNet UI.

This journey has been filled with learning, troubleshooting, and immense satisfaction. I'm excited to continue refining my skills and sharing more cosmic discoveries with you all!