NGC6888 (Crescent Nebula)

Date: June 11, 2005
Location: Fremont Peak, CA
Scope: Takahashi FS102 @ 800mm
Guiding: Vixen 60mm refractor with SBIG ST-4
Mount: Losmandy G-11
Camera: SBIG ST2000XM
Filters: Custom Scientific in FLI CFW
Exposure details:
4x20min Hydrogen Alpha for red
2x20min OIII for green
3x20min Sulfur for blue
Processing: MaximDL for calibration, alignment and combining.  PSCS for final processing

Notes: This faint crescent of nebulosity in the constellation Cygnus has significant oxygen and sulfur emission lines, in addition to the common hydrogen alpha emission line found in many nebulae.  The jellyfish shaped crescent appears to be floating in a sea of ionized red hydrogen gas.