Quite a big improvement over the last image of Orion I posted, and the two other attempts in between that I didn’t post. This is mainly due to the addition of an OG star tracker that has allowed me to take 30" sub exposures and helped me to increase my total integration time. So this was:

  • 407 * 30" exposures
  • 50 dark frames
  • 50 flat frames
  • 50 bias frames

shot with:

  • Sony A7Cii
  • Minolta 75-300mm f/4.5-5.6 @ 300mm f/5.6
  • OG star tracker

and my processing steps were:

  • calibration, registration and stacking in Siril v1.2.0
  • background extraction, stretching, colour calibration, and noise removal again in Siril
  • final levels adjustment and crop in darktable.