NGC7822 emission nebula with open cluster and star-forming complex. Narrowband Image with HSHO filters as LRBG (see below for explanation).
Boren Simon 8" Powernewt with ASA f/2.8 2KORRR reducer/corrector
SBIG ST-8300M CCD camera with FW8-8300 Filter Wheel (LRGBHOS)
Orion Mini Autoguider Guide Scope w/Fishcamp Starfish guide camera
This is an image produced by a monochrome camera, using filters to image the red, green, and blue colors separately, and then they are combined in software to generate a color image. In this case, special "narrowband" filters were used (instead of simple red, green and blue) that take small slices of the visible light spectrum. Each of the filters reveals the presence of certain chemical elements in the stars, nebula, and gases in space. Sulfur, Hydrogen, and Oxygen (SHO) are represented here as red, green and blue, and combined into a full color image. For example, the blue areas of the nebula are rich in oxygen. So, when done like this, the pretty pictures can actually help map out which chemical elements make up the nebula!
885 mins total exposure (14.75 hrs)
Luminance: Hydrogen: 105x300s
Red: Sulfur-II: 36x300s
Green: Hydrogen-alpha: 105x300s
Blue: Oxygen-III: 36x300s