• Arp 317, The Leo Triplet
  • M44
    Annotated image
  • The galaxies M65, M66, and NGC 3628 comprise the Leo Triplet
  • or the M66 group.  The goal for this picture was to concentrate
  • on quality so the spray of stars from NGC 3620 could be
  • showcased.  The Leo Triplet is about 35 Mly from us.
  • Hover over the picture for an annotated version
  • Date:  8 and 9 March and 20 April 2026
  • FOV:  approximately 105' × 70'; the angular size of
  • NGC 3628 is 14' × 3.6', the star spray is about 41'
  • Rotation:  165.104°
  • Telescope:  Stellarvue SVX102T + SFFX-1 flattener (714mm, f/7)
  • Guiding:  ZWO ASI120MM mini mono guide camera,
  • Stellarvue F050G 50mm guide scope
  • Computer:  ASIair pro Raspberry Pi
  • Mount:  ZWO AM5
  • Camera:  ZWO ASI6200MC Pro Cooled (-10°C) Color CMOS, APS/c ROI
  • Pixel size:  3.76 µm
  • Resolution:  1.052 arcsec/pixel
  • Filter:  Optolong UV/IR cut
  • Frames:  all subs are 300 seconds and 100 gain
  • fifty-nine frames 8 March2026
  • sixty-seven frames 9 March2026
  • sixty-three frames 20 April2026
  • Stacking:  one hundred eighty-nine frames using PixInsight
  • Total Time:  15 hours and 45 minutes
  • Processing:  Pixinsight – SPPC, DBE, SPCC, BXT, NXT → Linear
  • MAS, MStr, GHS, HST, PMath MAS + MStr + GHS + HST
  • → Stars, Sat,
  • StarXT, MAS, MStr, GHS, HST, PMath MAS MStr + GHS + HST
  • → Starless, HDR68PhLm, Sat
  • PMath ~(~Stars*~Starless) → Blend, scale
  • Location:  Darling Hill Observatory near Vesper, NY