Celestial hemisphere:  Northern  ·  Constellation: Cepheus (Cep)
OU-4 Squid Nebula, Kathy Walker
OU-4 Squid Nebula
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OU-4 Squid Nebula

OU-4 Squid Nebula, Kathy Walker
OU-4 Squid Nebula
Powered byPixInsight

OU-4 Squid Nebula

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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.

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  • 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.

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OU-4 Squid Nebula, Kathy Walker