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FROM THE OBSERVATORY · 16-Aug-2016

Narrowband Helix Nebula

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Narrowband Helix Nebula
I've already done the Helix Nebula in natural colour, so I've imaged it again in narrowband. Lots of H-alpha and Oxygen-III, but barely any Sulfur-II.
BEHIND THE IMAGE

Notes from the session

Image:

34x 1200s H-alpha bin1x1 + 20 flat + 50x dark + 120x bias
33x 1200s SII bin1x1 + 12 flat + 50x dark + 120x bias
17x 1200s OIII bin1x1 + 12 flat + 50x dark + 120x bias


Total exposure 28 hours.

Hardware:

Skywatcher Black Diamond ED120
SkyWatcher EQ8 Pro Mount
QSI 683-ws8 Camera @ -15°C
Astronomik 6nm Ha, 6nm OIII, 6nm SII filters
Starlight Xpress Lodestar X2 Autoguider
Innovations Foresight On Axis Guider
Starlight Instruments Focus Boss II



Location:

Orange zone in Brisbane, Australia. (Bortle 7)
Imaged over 4 nights.



Software:

Planning & camera alignment with Aladin 9
Captured with AstroArt 6
Guiding with PHD2 + PHD_Dither
FocusLock live focusing
CCDInspector: Image analysis & rejection
CCDStack 2+: Calibrate, align, stack.
Photoshop CC: Noise reduction, shadows/highlights, high pass filter, levels, curves, combine as HSO, color balance, saturation, rotation.