Rho Ophiuci Nebula. Rho is the bright triple star. Nebulosity extends far beyond this 1.8 degree field and reaches beyond Antares, which is 2 degrees to the south. North is up.
RGB 7x5 min each. 12.5 inch f/3.6 home-built astrograph on 9 inch Schaefer mount. Apogee Alta U16 camera, 37x37mm sensor.
full exif