My wife asked me why I include all this technical goobage, and I told her it as included for all the other astrophotographers and amateur astronomers out there. So, she replied “you mean all 5 of them!” Anyway, here it comes:
The Sadr Region (also known as IC 1318 or the Gamma Cygni Nebula) is the diffuse
emission nebula surrounding the star Sadr at the center of constellation Cygnus’s cross. This region is one of several surrounding nebulous regions, including the Butterfly Nebula and the Crescent Nebula.
The Crescent Nebula (also known as NGC 6888 or Sharpless 105), located near the center of both images, is an emission nebula that is about 5000 light-years (29,400 billion miles) away from Earth. It is formed by the fast stellar wind from the Wolf-Rayet WR 136 colliding with and energizing the slower moving wind ejected by the star when it became a red giant a out 250,000 to 400,000 years ago. The result of the collision is a shell and two shock waves, one moving outward and one moving inward.
The image on the top was taken using a telescope in a Bortle 2 area back in March, with a focal length of 448mm. The lower image was taken in a Bortle 6 area using the same Astro-dedicated camera, connected to a lens with a 135mm focal length. The wider field of view reveals the Butterfly nebula in the lower left. Sadr is the bright star located just above the Butterfly.
The top image is comprised of 20 stacked subs @ 600s (200m or 3.3 hrs) and was calibrated using 60 dark frames, 60 bias frames, and 60 flat images. It was stacked using the python script Sirilic and was post-processed with Siril and Photoshop.
The lower image is comprised of 18 @ 300s, 20 @ 180s, and 30 @ 60s (180m or 3 hrs) and was calibrated using 60 dark frames, 60 bias frames, and 60 flat frames. It was stacked using the Siril, in Ha and O3, and post-processed with Siril, GIMP, and Photoshop.
Equipment:
• Telescope: SVBony SV503 80ED 560mm, F/7 Refractor with a 0.8 Reducer/Flattener (Top image, reduced focal length 448mm)
• Lens: (Lower image) Rokinon 135mm f/2 (I used f/2.8)
• Mount: SkyWatcher HEQ5 Pro
• Camera: ZWO ASI2600 MC Pro with 100 gain
• Filter: Optlong L-enHance for lower image
• Guiding: ZWO ASI120mm Mini Monochrome Guide Camera with the ZWO 30mm f/4 Guide Scope
• Automation: ZWO ASIAir Mini