Mike Lewis
Staff Member
CTB1 is a faint supernova remnant in the constellation Cassiopeia, also known as the "Garlic Head Nebula" or Abell 85. Initially mistaken for a planetary nebula, it is the expanding shell of gas and dust from a star's explosion about 10,000 years ago.
Sh2-170, commonly referred to as the Little Rosette Nebula for its resemblance to the Rosette Nebula, , is the much brighter object in the left of the image.
The very faint CTB1 required my longest total integration yet and 20 minute subframes to bring out lots of detail. It was a challenge not to blow out the much brighter Sh2-170 under these collection conditions. As always, any comments,critiques, or questions are most welcome. A larger version is also available over on my Astrobin site:
https://app.astrobin.com/u/mlewis?i=oq1oma#gallery
Equipment:
Poseidon-M Camera @ -5C and
Gain:125 Offset:25
Astro-Physics Mach2 Mount
Williams Optics Cat 91 Refractor, 448mm @ f/4.9
Antlia Pro Filters (3nm narrowband plus RGB)
Askar FMA180 Guide scope with ASI290MM
Software:
Pixinsight Commercial Version 1.9
Lightroom CC
Photoshop CC
N.I.N.A. Control Software
BlurXTerminator (Russell Croman)
StarXTerminator (Russell Croman)
NoiseXTerminator (Russell Croman)
Astro-Physics APCC and APPM
Light Frames:
Gain 125 / Offset 25
Red: 19 x 120 secs (38 mins)
Green: 18 x 120 secs (36 mins)
Blue: 17 x 120 secs (34 mins)
Hα: 25 x 1200 secs (8 hrs 20 mins)
Oiii: 50 x 1200 secs (16 hrs 40 mins)
Sii: 35 x 1200 secs (11 hrs 40 mins)
38 hrs 28 mins total
Dark Frames:
10 x 120 secs (20 mins)
10 x 1200 secs (3 hrs 20 mins)
Sh2-170, commonly referred to as the Little Rosette Nebula for its resemblance to the Rosette Nebula, , is the much brighter object in the left of the image.
The very faint CTB1 required my longest total integration yet and 20 minute subframes to bring out lots of detail. It was a challenge not to blow out the much brighter Sh2-170 under these collection conditions. As always, any comments,critiques, or questions are most welcome. A larger version is also available over on my Astrobin site:
https://app.astrobin.com/u/mlewis?i=oq1oma#gallery
Equipment:
Poseidon-M Camera @ -5C and
Gain:125 Offset:25
Astro-Physics Mach2 Mount
Williams Optics Cat 91 Refractor, 448mm @ f/4.9
Antlia Pro Filters (3nm narrowband plus RGB)
Askar FMA180 Guide scope with ASI290MM
Software:
Pixinsight Commercial Version 1.9
Lightroom CC
Photoshop CC
N.I.N.A. Control Software
BlurXTerminator (Russell Croman)
StarXTerminator (Russell Croman)
NoiseXTerminator (Russell Croman)
Astro-Physics APCC and APPM
Light Frames:
Gain 125 / Offset 25
Red: 19 x 120 secs (38 mins)
Green: 18 x 120 secs (36 mins)
Blue: 17 x 120 secs (34 mins)
Hα: 25 x 1200 secs (8 hrs 20 mins)
Oiii: 50 x 1200 secs (16 hrs 40 mins)
Sii: 35 x 1200 secs (11 hrs 40 mins)
38 hrs 28 mins total
Dark Frames:
10 x 120 secs (20 mins)
10 x 1200 secs (3 hrs 20 mins)
