Casitas de Gila, Gila, NM, October 6 - 9, 2023

IC 5146 is a star forming region  in the constellation Cygnus.  It is a favorite summer target for astrophotographers.  The emission nebula is part of a large molecular cloud that spans across the image.  The region also has a hydrogen emission region that appears red in the background.  The star cluster in the Cocoon is about 4,000 ly away, and the central star that lights it formed about 100,000 years ago.  The nebula is about 12 arcmins across the sky, which is about 15 light years across.  Barnard 168 is the dark nebula that appears in most images as a long black lane that appears to trail from the Cocoon.  In this image, the molecular clouds are more complex.  

Image processing was one hot mess, a dumpster fire, a disaster.  PixInsight’s WBPP script created vertical line artifacts in some of the integrated masters, including 2x drizzle files.  I ran the script several times changing the workflow, but the artifacts would then appear in different channel masters!?!  So, I reverted to calibrating, aligning and integrated the subframes manually in PixInsight.  The next issue arose with GraXPert’s AI based gradient removal in the beta version.  It worked flawlessly on other image datasets.  For the Cocoon, it created significant artifacts that ruined the combined RGB color image.  So, I reverted to creating a grid in a rich star field to remove color gradients.  Next, StarXTerminator failed to remove larger stars in 2X drizzled images.  While this is a known problem, it has worked well on other images.  To add insult to injury, the ImageSolve script failed to solve XISF format images saved in GraXpert.  The astrometric solution was not saved with the processed image.  Therefore, the SPCC tool could not do a color calibration.  The next challenge was in combining the processed and stretched Ha image with the luminance and RGB images.  I cannot count how many iterations I went through to get a reasonable result.  Combining the Ha-Lum image with the HaRGB image also proved challenging.  I am still not satisfied with the final image as the color of the faint molecular cloud has a bit too much green in it.  I was exhausted at the end of this multi-day marathon.  Time to move on.

Imaging details:

Stellarvue SVX102T refractor with 0.74x focal reducer (FL = 528mm, f/5.2)
ZWO large off-axis guider with a ZWO ASI 174MM mini guide camera
Losmandy G11 mount with Gemini 2
ZWO ASI 2600MM Pro cooled monochrome camera (-10C)
Chroma 36mm Hydrogen-alpha, Luminance, Red, Green, and Blue filters
Equatorial camera rotation: 0 degrees

Software:    Sequence Generator Pro, ASTAP plate solving, PHD2 guiding, 
    Losmandy Gemini ASCOM mount control and web client interface,
    SharpCap Pro for polar alignment with a Polemaster camera,
    PixInsight 1.8.9-2,
    Photoshop 2023

Hydrogen-a 10 min x 12 subframes (120 min), Gain 100, Offset 32, 1x1 binning
Luminance  2 min x 68 subframes (136 min), Gain 100, Offset 32, 1x1 binning
Red             4 min x 30 subframes (120 min), Gain 100, Offset 32, 1x1 binning
Green          4 min x 27 subframes (108 min), Gain 100, Offset 32, 1x1 binning
Blue            4 min x 27 subframes (108 min), Gain 100, Offset 32, 1x1 binning

Total integration time: 9.9 hours