NGC 1491: Capturing the 'Fossil Footprint Nebula' with a DSLR
This image showcases NGC 1491, an intriguing emission nebula located in the constellation Perseus, approximately 10,700 light-years away from Earth. Nicknamed the 'Fossil Footprint Nebula' for its distinctive shape, this celestial object presents a unique challenge and reward for astrophotographers.
The Challenge of Faint Nebulosity
Imaging NGC 1491 with a DSLR and a United Hydrogen Carbon (UHC) filter proved to be a demanding endeavor. Despite an integration time of over 4 hours, the subtle surrounding nebulosity remained elusive, a common hurdle when working with faint deep-sky objects. The nebula's relatively small apparent size within the Field of View (FOV) at a focal length of 1280mm further amplified the difficulty, especially compared to capturing broader emission regions.
Achieving the Signature Glow
Despite these challenges, the perseverance paid off. The characteristic pinkish glow of the nebula, indicative of ionized hydrogen, was successfully rendered. Additionally, the dark dust lanes that snake through NGC 1491, obscuring light from behind, were also brought to light, adding depth and texture to the final image.
Technical Details of the Capture:
- Object: NGC 1491 – Emission Nebula
- Capture Location & Conditions: Bortle 4 skies
- Total Integration Time: Approximately 4 hours
- Telescope: Celestron NexStar 8SE SCT (203mm aperture, f/6.3 with focal reducer)
- Camera: Sony a6400 (unmodified DSLR)
- Mount: Celestron NexStar mount on wedge, controlled via ASCOM in NINA
- Guiding: ZWO ASI120MM Mini + 30mm guide scope, PHD2
- Filters: 2” UHC filter
- Exposure Details: Approximately 240 x 60-second light frames
- Calibration Frames: 30 dark frames, 75 bias frames, 50 flat frames
- Software Used: NINA (acquisition), PHD2 (guiding), Siril (stacking), Photoshop (post-processing)
This image is a testament to the dedication required in astrophotography, pushing the limits of equipment and technique to reveal the hidden beauty of the cosmos.
