8/26/2012 NGC 7380
After nearly a year since our last post, I’m happy to be able to present our biggest project of the summer!
Back in 2011, one of the very first narrowband subjects I attempted was NGC 7380 – aka The Wizard nebula. Unfortunately there were a number of problems with that original dataset, and I had always wanted to give it another try. Presented here are the results of that effort.
From the wikipedia article, “NGC 7380 (also known as the Wizard Nebula) is an open cluster discovered by Caroline Herschel in 1787. William Herschel included his sister’s discovery in his catalog, and labelled it H VIII.77. It is also known as 142 in the 1959 Sharpless catalog (Sh2-142). This reasonably large nebula is located in Cepheus.”
As with my earlier attempt, this version of NGC 7380 is presented in Hubble palette. Hubble palette is a popular scheme for using color to help astronomers identify the chemical composition of the different areas of the image. Hubble palette is defined as follows:
Red = S II (ionized sulfur)
Green = HA (hydrogen alpha)
Blue = O III (doubly ionized oxygen, having two electrons removed)
And here are the technical details:
NGC 7380 – The Wizard Nebula
LRGB image using Ha for Luminance, SII for Red, OIII for Blue and Ha for Green
Astrodon filters (new for this year!) 5nm HA, 5nm SII and 3nm OIII
41 exposures of OIII, with 20 minute subs each
25 exposures of SII, with 20 minute subs each
45 exposures of HA, with 20 minute subs each
Imaging scope: Astro-Tech AT10RC Ritchey Chrétien at f/6.7 (native f/8)
Focal reducer: Astro Physics CCDT67 focal reducer
Imaging camera: QSI 583wsg monochrome
Guide camera: Starlight Xpress Lodestar
Mount: Celestron CGE hypertuned by Deep Space Products
Capture and stacking in Maxim DL
All other processing in Photoshop
Over 39 hours of starlight exposures went into this project.