Optics/mount : 12″ACF 2.7m AP-Reduzer Alt-5 Camera/filters: Atik 11002 AstrodonHa/OIII/SII Exposure:32×600 Ha, 14×600 OIII/SII all 2bin 25-26 Juin 2015 The Omega Nebula, also known as the Swan Nebula, Checkmark Nebula, and the Horseshoe Nebula (catalogued as Messier 17 or M17 and as NGC 6618) is an H II region in […]