Mike Lewis
Staff Member
Due to weather, travel, seeing, possible gear gremlins, and being involved with some other activities that are currently taking up my time in the evenings, it has been a challenge to really get much good DSO astro data lately. I finally was able to put together a few nights of imaging on the Clamshell Nebula (Sh2-119) though and got some results I like.
This is a straight SHO channel combination of individual starless 10 minute subs in Hα, OIII, and SII, followed by using the narrowband normalization process in PixInsight which was used to reduce but not remove the green. After that, some more tweaking in PixInsight, Photoshop and Lightroom. Stacks of separate 30 second subs in RGB were used for the stars. This target emits in all 3 channels, and I found the SII signal to be uncharacteristically stronger than the OIII signal.
The Clamshell nebula is an emission nebula near The North America Nebula in the sky, in the constellation of Cygnus. It is thought to be approximately 2,200 light years distant. It is also known by its Sharpless catalog designation as Sh2-119. As always, comments and critiques most welcome.
Collection Details:
Equipment:
QHY268M Camera @ -5C and
Gain:56 Offset:20 / Gain:0 Offset 20
Software Bisque MyT Mount
Stellarvue SVQ100 Astrograph Refractor, 580mm @ f/5.8
Antlia Pro Filters (3nm narrowband plus LRGB)
QHY OAG-M/ASI290MM
Software:
Pixinsight Commercial Version 1.8
Lightroom CC
Photoshop CC
N.I.N.A. Control Software
BlurXTerminator (Russell Croman)
StarXTerminator (Russell Croman)
NoiseXTerminator (Russell Croman)
Light Frames:
Gain 56 / Offset 20
Ha: 26 x 600 secs (4 hrs 20 mins)
OIII: 28 x 600 secs (4 hrs 40 mins)
SII: 26 x 600 secs (4 hrs 20 mins)
Gain 0 / Offset 20
Red:18 x 30 secs (9 mins)
Green: 11 x 30 secs (5 mins 30 secs)
Blue: 15 x 30 secs 7 mins 30 secs)
13 hrs 42 mins total
Dark Frames:
10 x 30 secs (5 mins)
10 x 600 secs (1 hr 40 mins)
This is a straight SHO channel combination of individual starless 10 minute subs in Hα, OIII, and SII, followed by using the narrowband normalization process in PixInsight which was used to reduce but not remove the green. After that, some more tweaking in PixInsight, Photoshop and Lightroom. Stacks of separate 30 second subs in RGB were used for the stars. This target emits in all 3 channels, and I found the SII signal to be uncharacteristically stronger than the OIII signal.
The Clamshell nebula is an emission nebula near The North America Nebula in the sky, in the constellation of Cygnus. It is thought to be approximately 2,200 light years distant. It is also known by its Sharpless catalog designation as Sh2-119. As always, comments and critiques most welcome.
Collection Details:
Equipment:
QHY268M Camera @ -5C and
Gain:56 Offset:20 / Gain:0 Offset 20
Software Bisque MyT Mount
Stellarvue SVQ100 Astrograph Refractor, 580mm @ f/5.8
Antlia Pro Filters (3nm narrowband plus LRGB)
QHY OAG-M/ASI290MM
Software:
Pixinsight Commercial Version 1.8
Lightroom CC
Photoshop CC
N.I.N.A. Control Software
BlurXTerminator (Russell Croman)
StarXTerminator (Russell Croman)
NoiseXTerminator (Russell Croman)
Light Frames:
Gain 56 / Offset 20
Ha: 26 x 600 secs (4 hrs 20 mins)
OIII: 28 x 600 secs (4 hrs 40 mins)
SII: 26 x 600 secs (4 hrs 20 mins)
Gain 0 / Offset 20
Red:18 x 30 secs (9 mins)
Green: 11 x 30 secs (5 mins 30 secs)
Blue: 15 x 30 secs 7 mins 30 secs)
13 hrs 42 mins total
Dark Frames:
10 x 30 secs (5 mins)
10 x 600 secs (1 hr 40 mins)
