Getting plate-solving status, please wait...
The Lobster Nebula - NGC 6357 (H-alpha), 


            Min Xie

The Lobster Nebula - NGC 6357 (H-alpha)

Getting plate-solving status, please wait...
The Lobster Nebula - NGC 6357 (H-alpha), 


            Min Xie

The Lobster Nebula - NGC 6357 (H-alpha)

Technical card

Imaging telescopes or lenses: Takahashi FSQ-85EDP

Imaging cameras: ASI1600mm Pro

Mounts: Astro-Physics Mach1GTO CP3

Guiding telescopes or lenses: QHYCCD QHYOAG-M

Guiding cameras: ZWO ASI120mm-Mini

Focal reducers: Takahashi Flattener 1.01x

Software: StarNet++  ·  Adobe Lightroom Classic 2019  ·  Adobe Photoshop 2019 CC  ·  Astro Pixel Processor  ·  Sequence Generator Pro  ·  PixInsight 1.8 Ripley

Filters: Astrodon 3nm Ha 31mm

Accessory: PrimaLuceLab Sesto Senso Robotic Focusing Motor  ·  ZWO EFW  ·  Kingdel NC860 (i7-8550U)

Dates:July 24, 2019July 25, 2019

Frames:Astrodon 3nm Ha 31mm: 39x300" (3h 15') (gain: 139.00) -10C bin 1x1

Integration: 3h 15'

Darks: 40

Flats: 40

Bias: 60

Avg. Moon age: 22.10 days

Avg. Moon phase: 50.53%

Bortle Dark-Sky Scale: 9.00

Mean SQM: 18.00

Temperature: 30.50

Basic astrometry details job: 2827992

Resolution: 4103x2735

Locations: Backyard, Coppell, Texas, United States

Data source: Backyard


Heard this target from one my astrophotography buddies. Pulled out the Sky Guide App on the phone and checked if it's in my shooting range. From my backyard, the lobster is basically a tad above the tree lines and neighbors' roofs. The cool thing is, it dances its way along the line and could give me 2~3 hours of imaging time before 1:00am.

I never thought this is pretty hard until I got started. The target is extremely low and the scope is literally pointing and neighbors' roof top. Downtown Dallas is right on the direction where the scope is aiming at and the sky glow is that strong. My dear neighbor has the routine to play with the dog in their backyard from 9pm to 10pm with the garage door light on all night long. There is a thumbnail picture I attached in Revision B to show how low the scope is pointing.

But it's fun. The data is not the best and the amount of data is definitely not enough. I like it somehow. I might do this target again. Maybe. Collecting other channels especially O3 will be a big challenge from the backyard though.

Pre-processing of Ha Master

- Calibration / Integration, Astro Pixel Processor

- Dynamic Background Extraction, PixInsight

- Deconvolution, PixInsight

- MultiscaleLinearTransformation (Denoise), PixInsight

- ScreenTransferFunction / HistogramTransformation, PixInsight.


- Final touch up and export, PhotoShop