The Grand Pleiades star cluster

Edit 10/25/2021: This image was featured by AAPOD 2! You can check it out here: https://www.aapod2.com/blog/grand%20pleiades

Perhaps the most famous star cluster on the sky, the bright stars of the Pleiades can be seen without binoculars from even the depths of a light-polluted city. With a long exposure from a dark location, though, the dust cloud surrounding the Pleiades star cluster becomes very evident.

Two techniques were used to get this image: framing selection and downsampling. I chose only about 65% of the frames that I actually shot, removing bad signal from out of focus, cloudy, or polluted frames. I also downsampled the image by 50% increasing snr and the amount of dust I imaged.

Image:

Click for full quality image

Equipment:

  • Nikon D90
  • Sigma 300mm prime lens
  • Sky-Watcher Star Adventurer
  • Star Adventurer Tripod
  • Bahintov Mask
  • Intervalometer
  • DIY diffraction spikes
  • Stellarium
  • All Sky Plate Solver
  • Nina

Acquisition:

  • ISO 800, f/4.0
  • Taken from a bortle 2 zone during the new moon.
  • Taken on 10/4, 10/6, 10/7, 10/8
  • 231 x 3′ light frames (11.2 hours)
  • 200 total flat frames
  • 67 dark frames
  • 200 bias frames

Processing:

  • WBPP for calibration
  • Normalize scale gradient +ESD stacking
  • Crop away stacking artifacts
  • DBE
  • Color calibration
  • Noise reduction
  • Repair HSV separation
  • ArcsinH stretch
  • Starnet + exponential transform + pixel math to enhance nebulosity
  • MMT, histogram transformation, curves transformation, Local histogram – Multiscale processing
  • HDR multiscale transform
  • Local histogram equalization
  • Curves transformation

Share whatever you think is interesting about astronomy and astrophysics here!