Hemisphere:  Northern  ·  Constellation: Cepheus (Cep)
Getting plate-solving status, please wait...
OU-4 Squid Nebula, 



    
        

            Kathy Walker
OU-4 Squid Nebula
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OU-4 Squid Nebula

Getting plate-solving status, please wait...
OU-4 Squid Nebula, 



    
        

            Kathy Walker
OU-4 Squid Nebula
Powered byPixInsight

OU-4 Squid Nebula

Acquisition details

Dates:
June 21, 2020 ·  June 9, 2021 ·  June 10, 2021 ·  June 12, 2021 ·  May 20, 2022 ·  May 23, 2022
Frames:
Astrodon H-alpha 5nm: 20×600(3h 20′) bin 1×1
Astrodon OIII 5nm: 80×900(20h) bin 1×1
Astrodon RGB: 24×120(48′) bin 2×2
Integration:
24h 8′
Avg. Moon age:
12.23 days
Avg. Moon phase:
20.32%

Basic astrometry details

Astrometry.net job: 5792122

RA center: 21h12m25s.4

DEC center: +59°5620

Pixel scale: 1.203 arcsec/pixel

Orientation: 1.705 degrees

Field radius: 0.674 degrees

Resolution: 3260x2381

File size: 1015.8 KB

Locations: Hall's Harbour Observatory (H2O), Hall's Harbour, NS, Canada

Data source: Backyard

Description

This might be the toughest target I have worked on. The Squid is a really, really, REALLY faint Oiii emission nebula, within the larger SH2-129 Ha emission nebula. It is so faint that, in spite of its large size, it was only discovered in 2011.

It takes a lot of Oiii data to capture the Squid. The original version had 13.25 hours of it, all captured on moonless nights from a Bortle 3 site. Even so, it was buried in noise, and required some dodgy masking to bring it out. I was not happy with the star haloes in the nebula, due to the extreme stretching required, but I lived with it in 2021.

In 2022, I added another 7 hours of Oiii and nearly 3 hours of Ha.  The 50% increase in Oiii made the difference in being able to stretch the Squid properly without excessive noise.  It could still benefit from more time, so updating this image may become an annual event.

Comments

Revisions

  • OU-4 Squid Nebula, 



    
        

            Kathy Walker
    Original
  • Final
    OU-4 Squid Nebula, 



    
        

            Kathy Walker
    B

B

Description: Added more data. Finally, I am able to pull the Squid out of the background. Squid is O3; background is Ha, and the stars are RGB.

Uploaded: ...

Sky plot

Sky plot

Histogram

OU-4 Squid Nebula, 



    
        

            Kathy Walker