IC 5070 - The Pelican Nebula in SHO
Date: October 15th, 2020
Cosgrove’s Cosmos Catalog ➤#0057
IC 5070 - The Pelican Nebula - as captured in narrowband with the Astro-Physics 130mm Platform (click image for ful resolution via Astrobin.com)
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About the Target
IC 5070 - The Pelican Nebula. This rich region of gas and dust is located 1800 light-years away in the constellation of Cygnus, the Swan. It is separated from the North American Nebula by a dark region of dust. The Pelican Nebula is very active in star formation and the growing collection of hot new stars being created there are slowly transforming cold gasses to hot gases that are ionized.
The Annotated Image
The annotated image was created using the ImageSolver and AnnotateImage scripts in Pixinsight.
About the Project
I shot this target about a year ago using the One-Shot Color Camera. At the time, I could not see why it is called the Pelican Nebula. As this is a region that is rich in ionized gas, I decided to try again and this time use the Mono camera and Narrowband filters to take images using Hydrogen-Alpha, Oxygen-3, and Sulfur-2 filters. With this result, I can clearly see the "pelican" in this image. Can you?
My original plan was to gather a lot more data than I here. Of course, this is always been my plan for all of my images. Nature - specifically weather - often laughs at me and lets me know who is really the boss here.
As we enter the fall season, we get a lot of clouds and clear nights become harder to come by. We had one clear evening the other night and I was able to get about 3.5 hours of integration time collected before a cloud deck came in and shut me down. Ideally - I like to get at least one or maybe two more nights of data on this. Even though I was light on integration, I was curious to see what I had here, so I processed this initial image. I was not expecting too much since I only had about an hour per filter, but with some careful noise reduction, I was surprised that it looks as good as it does. Not where I want to end up, but not too bad of a start. As it turned out - this was the final result as I never had another opportunity to gather more subs. So it will have to for now.
I also had another challenge. 57 Cygni caused significant halo artifacts with two of my filters - the O3 and the S2. I have been using the ZWO Narrowband Gen II filters and not having problems with them. Of course, earlier images did not have a bright star in the field.
It took a lot of processing to diminish these artifacts - so I think I will be upgrading my filters in the near future. I hate to go through this trouble and end up with artifacts that I know could be avoided!
I should also mention that I like to take RGB images of these narrowband targets so I can replace the narrowband stars with RGB stars that look more natural. Unfortunately, the clouds moved in before I could capture those images, so these stars have no color - as is typical with many narrowband images.
Previous Effort
I first imaged IC 5070 in September of 2019 after only having the first telescope up and running for a month or so. The post for that earlier attempt can be seen HERE.
Here is a side-by-side comparison:
2019 version of the Pelican Nebula (Click to zoom)
2020 version of the Pelican Nebula - rotated a bit from the 2019 version (Click to zoom)
The Location in the Sky
IAU/Sky & Telescope Constellation map showing the location of the Pelican Nebula indicated by a yellow arrow.
Capture Details
Light Frames
17 x 300 seconds, bin 1x1 @ -15C, unity gain, ZWO Gen II Ha Filter
12 x 300 seconds, bin 1x1 @ -15C, unity gain, ZWO Gen II O3 Filter
12 x 300 seconds, bin 1x1 @ -15C, unity gain, ZWO Gen II S2 Filter
Total of 3.4 hours
Cal Frames
50 Bias exposures
25 Dark exposures
50 Ha Flats
50 O3 Flats
50 S2 Flats
Capture Hardware
Scope: Astrophysics 130mm Starfire F/8.35 APO refractor
Guide Scope: Televue 76mm Doublet
Camera: ZWO ASI1600mm-pro with ZWO Filter wheel with ZWO filter set
Guide Camera: ZWO ASI290Mini
Focus Motor: Pegasus Astro Focus Cube 2
Camera Rotator: Pegasus Astro Falcon
Mount: Ioptron CEM60
Polar Alignment: Polemaster camera
Software
Capture Software: PHD2 Guider, Sequence Generator Pro controller
Image Processing: Pixinsight, Photoshop - assisted by Coffee, extensive processing indecision and second-guessing, editor regret and much swearing…..
Standardizing the base
Finally, the Tri-Pier and the its extension column arrived. This allowed me to standardize the base of the two telescope platforms. There are several reasons that made this useful. First - everything is the same when you are handling things in the dark. And secondly, I was in the process of revolutionizing how I setup at night…..