Day: March 28, 2020

The Rosette in Black & White

The Rosette Nebula
The Rosette Nebula in Black and White
  • Telescope: Stellarvue SVA130T-IS
  • Mount: Losmandy G-11 with Gemini 2 controller
  • Autoguiding: Yes
  • Optical Configuration: 0.72x field flattener & reducer (f/5)
  • Filter(s): H-alpha narrowband (Baader 7-nm); O-III narrowband (Baader 8.5-nm)
  • Camera: ZWO ASI1600-MM Cool
  • Light Frames: 70, 2-min. O-III subs; 50, 2-min. H-alpha subs
  • Calibration Frames: 50 darks, 100 biases, 30 flats per filter
  • Total Exposure Time: 240 min. [(70 + 50) x 2 min.]
  • Gain: 75
  • Sensor Temperature: -10° C
  • Pre-Processing: PixInsight, DeepSkyStacker
  • Color Mapping: Luminance Channel = 80% H-alpha; Red Channel = 100% H-alpha; Green Channel = 40% O-III; Blue Channel = 40% O-III
  • Processing: Photoshop CC
  • Imaging Location: Los Angeles, Calif.

This black-and-white image of the Rosette Nebula has been processed from the color-mapped version originally shot in H-alpha and O-III light.