Sharpless 157, also known as the Lobster Claw Nebula, is a bright emission nebula in the constellation Cassiopeia.
It lies just south of the better-known Bubble Nebula (NGC 7635), pictured above it here. You will find more info and higher a resolution image of the bubble, elsewhere on my web site.
I would not normally do so much time with the Ha filter but I had problems with the initial 33 subs. I did another 20 to check on the problem.....then found best answer was to add the 20 & 33 into the final image. At a total of over 35 hours - this is the longest exposure time I have done to date.....but I don't plan to make a habit of it........I really don't think it is worth it!
Imaging telescopes or lenses: Takahashi FSQ130ED
Imaging cameras: FLI ML16200 ADT
Mounts: Takahashi EM 400 Temma 2M
Guiding telescopes or lenses: Takahashi FS60CB
Guiding cameras: QHY CCD QHY 5 II
Focal Extender / Reducer: None
Software: Sequence Generator Pro SGP (for capture) PHD 2 (guiding), Astro Pixel Processor & PixInsight,
Filters: Astrodon Ha, SII, OIII,
Accessories: Robofocus Focuser, ATIK EFW3
Original Resolution: 4315 x 2855
Dates: 8th Aug to 17th August 2019
Frames:
Astrodon Ha 53 x 20'
Astrodon SII 26 x 20'
Astrodon OIII 28 x 20'
Total integration = 35 hours 40 Minutes.
Center (RA, Dec):(349.445, 60.750)
Center (RA, hms):23h 17m 46.911s
Center (Dec, dms):+60° 45' 01.182"
Size:1.89 x 1.89 deg
Radius:1.339 deg
Pixel scale:1.9 arcsec/pixel
Orientation:Up is 271 degrees E of N
It lies just south of the better-known Bubble Nebula (NGC 7635), pictured above it here. You will find more info and higher a resolution image of the bubble, elsewhere on my web site.
I would not normally do so much time with the Ha filter but I had problems with the initial 33 subs. I did another 20 to check on the problem.....then found best answer was to add the 20 & 33 into the final image. At a total of over 35 hours - this is the longest exposure time I have done to date.....but I don't plan to make a habit of it........I really don't think it is worth it!
Imaging telescopes or lenses: Takahashi FSQ130ED
Imaging cameras: FLI ML16200 ADT
Mounts: Takahashi EM 400 Temma 2M
Guiding telescopes or lenses: Takahashi FS60CB
Guiding cameras: QHY CCD QHY 5 II
Focal Extender / Reducer: None
Software: Sequence Generator Pro SGP (for capture) PHD 2 (guiding), Astro Pixel Processor & PixInsight,
Filters: Astrodon Ha, SII, OIII,
Accessories: Robofocus Focuser, ATIK EFW3
Original Resolution: 4315 x 2855
Dates: 8th Aug to 17th August 2019
Frames:
Astrodon Ha 53 x 20'
Astrodon SII 26 x 20'
Astrodon OIII 28 x 20'
Total integration = 35 hours 40 Minutes.
Center (RA, Dec):(349.445, 60.750)
Center (RA, hms):23h 17m 46.911s
Center (Dec, dms):+60° 45' 01.182"
Size:1.89 x 1.89 deg
Radius:1.339 deg
Pixel scale:1.9 arcsec/pixel
Orientation:Up is 271 degrees E of N
Sky Map
Annotated Images
Click on the lower annotated image for higher resolution