The Cocoon Nebula ... IC 5146
(Click on Picture for larger view)


Added August 22, 2019 ...
The Cocoon Nebula (also labeled as IC 5146, Caldwell 19, and Sh 2-125) is a reflection/emission nebula in the constellation Cygnus. The cluster is about 4,000 light-years away, and the central star that lights it formed about 100,000 years ago and is a stellar nursery where star-formation is ongoing. I took this 2hr 36min exposure Thursday night in my backyard where the light pollution index is a 'Bortle 6.5', which translates to an area of moderate light pollution. However, I used a new special filter to greatly reduce the unwanted artificial light ... the Altair Astro QuadBand OSC filter. I was very pleased with the results.

The Techy Stuff ... For those who want to know ...
Telescope: Orion 190 mm f/5.3 Maksoutov-Newtonian Astrograph
Mount: Celestron AVX
Mount controls: Celestron PWI V2.1.25
Camera: Altair #Hypercam 294c Pro TEC
Camera sensor temperature setting: 32F (0C)
Filter: Altair #QuadBand OSC Light Pollution
Capture software: #SharpCap Pro V 3.2
Guiding: PHD 2 (RMS error: 0.24 ... i.e. very good tracking)
Mount controls: Celestron PWI V2.1.25
Polar Alignment: QHY Pole Master
Light Frames used: 52 at 180 seconds / Gain: 10,000
Binning: 1x1
Dark Frames: 40
Bias Frames: 40
Flat Frames: 39
Stacked in Deep Sky Stacker V 4.2.2
Post Processed in PixInsight and Photoshop CC
Seeing Conditions: 8 (0-10, where 0 is total cloud cover)
Moon: No Lunar Interference
Bortle Light-Pollution zone: 6.5 (can barely see the Milkyway)
Air Temperature: 79F
Date: August 22, 2019
Location: Backyard, Savannah GA

Video at


Return to Pat Prokop's Heavenly Backyard Astronomy Page