• The Double Cluster and Stock 2
    • Boogeyman Nebula
    Annotated image
  • NGC 869 and NGC 884, The Double Cluster, and
  • Stock 2 are three open clusters in Perseus.
  • A part of the Heart Nebula is also visible.
  • Hover over the picture for an annotated version
  • Date:  20 November 2025
  • FOV:  Approximately 4° 30' × 3°:  the annotated circles for
  • NGC 869 and NGC 884 are about 30'
  • Telescope:  Askar FRA300 pro (300mm f/5 Petzval)
  • Guiding:  ZWO ASI120MM mini mono guide camera,
  • SVBony SV165 Mini 40mm f/4 guide scope
  • Computer:  ASIair pro Raspberry Pi
  • Mount:  ZWO AM5 mount
  • Camera:  ZWO ASI6200MC Pro Cooled (-10°C) Color CMOS
  • Pixel size:  3.76 μm
  • Resolution:  2.598 arcsec/pixel
  • Filter:  Optolong UV/IR cut
  • Stacking:  thirty-four 300 second frames using Pixinsight
  • Calibration:  20 darks, 20 flats, and 20 dark flats
  • Total Time:  2 hours 50 minutes
  • Processing:  Pixinsight – SPPC, DBE, SPCC, BlurXT, NoiseXT, DynCrop → Linear
  • MStr, GHS, HST, PMath MStr + GHS + HST → Stars, Sat,
  • StarXT, MStr, GHS, HST, PMath MStr + GHS + HST → Starless,
  • PMath ~(~Stars*~Starless) → Blend, scale
  • Location:  Darling Hill Observatory near Vesper, NY