The Cave Nebula - Sh 2-155 Caldwell 9

The cave nebula is an active star forming region in the constellation Cepheus. This nebula is composed of three different kinds of nebulae: emission, reflection, and dark. It is very interesting the different shapes that nebulae can form/be. The cave nebula is approximately 2,400 light-years away from earth and has apparent size of 60 arc-minutes in our sky.

SubFrame Totals

Ha: 19x300s

Oiii: 13x300s

Sii: 16x300s

Total Integration Time: 240m (4h)

Camera settings: 200 gain, 35 offset, -10°C

Bortle 3/4 Zone

Date imaged: 7/11/20

This is my second attempt at a SHO image, and I think that it turned out better because of the data. I shot at a higher gain with longer exposure time. The data could have used a lot more time, but I used all of the time that I had in the night. Just like my previous image, Sh 2-86, the image above has Sii in R, Ha in G, and Oiii in B.

Equipment

Sky-Watcher Esprit 100 ED

Sky-Watcher EQ6-R

ZWO ASI1600mm Pro

ZWO EFW 8-Position

Astrodon 31mm NB filters (5nm Ha, 5nm Sii, 3nm Oiii)

ZWO ASI290mm mini guide camera

ZWO OAG

PrimaLuceLab Eagle3S Control unit

PrimaLuceLab Sesto Senso 2 Robotic Focuser

PrimaLuceLab ECCO Temperature Control

DewNot Dew Heater Strap

QHY PoleMaster

Imaging Software

NINA Imaging Suite

PHD2 Guiding

PrimaLuceLab Accessory Software

QHY PoleMaster Software

EQMOD

RemoteDesktop

Processing:

Blink to detect satellites, planes

SubframeSelector to measure data quality

Stacked and calibrated in PixInsight using calibration dark, flats, dark flats, and bias frames

DynamicCrop

DynamicPSF for Deconvolution Masks

Deconvolution

MLT Noise Reduction

PixelMath for channel combination (SHO)

AutomaticBackgroundExtraxtor

PhotometricColorCalibration

SCNR - 0.8 Green Reduction

HistogramTransformation

ColorMask - Cyan

ColorMask - Magenta

Curves for Blue with Cyan mask

Curves for Red with Magenta mask

RangeSelection for mask

LocalHistogramEqualization

ACDNR