Mosaic of 2 frames. LRGB composite 14.5 hr total over 3 nights (2 months):
- Lum 31 x 7 min = 3.6 hr
- Red 32 x 7 = 3.7 hr
- Green 31 x 7 = 3.6 hr
- Blue 31 x 7 = 3.6 hr
The Lagoon Nebula (Messier 8, NGC 6523) at bottom right, is a large emission nebula and star-forming region in the constellation Sagittarius. Its smaller companion, the Trifid Nebula (Messier 20, NGC 6514) at upper right also contains a blue reflecion nebula.
There are several cataloged red emission nebulas to the left (east) of M8.
I combined frames of the Lagoon and Trifid in PixInsight using Mosaic By Coordinates, then Photometric Mosaic to blend the halves. The overall color was determined using Photometric Color Calibration.
The Lagoon is just visible by naked ye from a dark site and is easily seen in binoculars near the bright center of the Milky Way.