This image is a combination of 3 layers. Layer 1 is Hydrogen Alpha is a combination of 6 images, each of 300 seconds. Layer 2 is Sodium II is a combination of 6 images, each of 300 seconds. Layer 3 is Oxygen III is a combination of 8 images, each of 60 seconds. Each of the images was corrected with a dark frame and a flat field. The images taken with a SBIG STT-8300 3 CCD Camera attached to an Centurion 18” F/2.8 telescope.
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