Astrophotography · Galaxies

Pinwheel Galaxy

Captured and Processed by Ashratul Zannati Purnota

The object · NGC 5457

A detailed essay on Pinwheel Galaxy is coming soon.

বাংলায়

এই জ্যোতিষ্কের বিস্তারিত বাংলা বিবরণ শীঘ্রই যুক্ত হবে।

Photographer: Ashratul Zannati Purnota
Observing location: USA, Utah (37.700000,-113.700000)
Exposure: 28 min.
Telescope: Celestron RASA 11" (iTelescope - T68), 279/ 620 mm
Camera: Frontlit
Field of view: 2.2° x 1.46°(1.6 arcsec)
Image processing: Ashratul Zannati Purnota
Processing method: Seven 28-minute one-shot color exposures of the Pinwheel Galaxy from iTelescope 68 were first calibrated using bias, dark, and flat frames to correct for sensor noise and uneven illumination. The calibrated images were stacked to improve signal-to-noise ratio and reveal faint details. Background extraction removed gradients while preserving the galaxy’s structure. Spectrophotometric color calibration using the OSC Sony IMX071 sensor ensured accurate color representation. Histogram transformation (shadows 0, midtones 0.50, highlights 1) enhanced visibility of faint structures, followed by denoising in separate mode (strength 0.50) to reduce noise. Finally, sharpening in both stellar and non-stellar modes enhanced fine details and star edges for a clearer, more detailed final image