The Cocoon Nebula (also Caldwell 19, Sh 2-125, and IC5146) is a reflection/emission nebula in the constellation Cygnus, located near the naked-eye star Pi Cygni, the open cluster NGC 7209 in Lacerta, and the bright open cluster M39. The cluster is about 4,000 ly away, and the central star that lights it formed about 100,000 years ago; the nebula is about 12 arcmins across, which is equivalent to a span of 15 light years.
Processing this image was harder than I thought. The O3 signal was very weak, considering the total time of exposure. I guess I need to capture some RGB an add this later to the image. That will also improve the star colours.
Setup:
Telescope: Astrosib RC250 @ f/6 f=1500mm
Camera: QHY9
Mount: Mesumount 2
Guiding: OAG with Lodestar
Exposure: 9x20min Ha (R) + 10x20min O3 (G&B)
Date: August 10th & 15th, 2013
Location: Overijse, Belgium
Bart Delsaert - Astrophotography 