M31 - Andromeda Galaxy: A Refined View
After an initial attempt that left me wanting more, I've revisited my capture of the Andromeda Galaxy, M31. This time, I focused on refining the processing workflow to achieve more accurate colors and resolve some initial star issues. The result is a significantly improved view of our closest galactic neighbor.
A New Approach to Stacking and Calibration
One of the key changes in this reprocessing was the stacking process. I opted to use DeepSkyStacker (DSS) for stacking, selecting the best 90% of my subframes to maximize signal while minimizing noise. While I'm familiar with DSS's capabilities for this, I'm still exploring similar functions in Siril.
Crucially, I implemented spectrophotometric color calibration, a technique that yielded much better results than the previous color calibration approach. This step was vital in bringing out the true colors of Andromeda.
Equipment Used:
- Camera: ZWO ASI585MC
- Lens: Canon EF 70-200mm f/2.8 L IS USM (set at 70mm)
- Mount: Skywatcher Staradventurer GTI
- Guide Camera: ZWO ASI120MM Mini
- Guide Scope: SVBONY SV165
- Power Supply: Jackery Explorer 300
Imaging Details:
- Subframes: 70 frames, each 5 minutes long
- Gain: 0
- Dithering: 5 pixels applied after every subframe
Processing Workflow:
- Stacking: Performed in DSS, utilizing 63 out of 70 subframes for a total integration time of 5 hours and 15 minutes.
- Siril Processing:
- Plate solving
- Cropping
- Background extraction
- Spectrophotometric color calibration
- Star removal using Starnet++
- Stretching the starless image
- Increasing color saturation on the starless image
- Desaturating stars in the star mask
- Recombining the starless image with the star mask
- Adjusting the star mask histogram for final touches
This refined process has brought out finer details within the dust lanes and enhanced the vibrancy of the galaxy's core. I'm excited to share this improved view and continue exploring different processing techniques in my astrophotography journey.
