Capturing the Crescent Nebula from Light-Polluted Los Angeles
Even under the challenging skies of Los Angeles, a Bortle 9 zone, remarkable astrophotography is achievable. This recent capture of the Crescent Nebula (NGC 6888) is a testament to the power of modern equipment and sophisticated processing techniques.
A Deep Dive into the Capture and Processing
The imaging session utilized a robust setup designed for capturing faint details:
- Telescope: 305 mm Reflector
- Camera: ZWO ASI533MC (-10 C)
- Filter: L-eNhance Dual Narrowband Filter
- Guide Scope: 50 mm Starboosa guidescope
- Guide Camera: ZWO ASI120MM
- Mount: ZWO AM5
- Accessory: ASIAIR Plus
The data was acquired on August 30, 2025, from the light-polluted environment of Los Angeles. The exposure consisted of 28 subs of 300 seconds each, with a gain of 100, demonstrating a significant integration time to overcome the ambient light.
The Processing Workflow
Achieving this level of detail from such a challenging location requires a meticulous post-processing workflow, primarily executed in PixInsight. The steps included:
- Background removal
- Spectrophotometric calibration
- BlurXTerminator for deblurring and noise reduction
- General noise reduction
- Histogram stretch for enhancing contrast
- Star removal for isolating nebular details
- Narrowband Normalization to balance color
- Curves transformation for fine-tuning luminosity and color
- Star recombination
- Final curves transformation for final adjustments
The result is a stunning image that highlights the intricate structures of the Crescent Nebula, proving that dedication and the right tools can conquer even the most significant light pollution.
