NGC6357 in Narrowband - Adam Lundie - Eatons Hill Observatory

NGC6357 in Narrowband

NGC6357 in Narrowband thumbnail
NGC6357 in Narrowband
NGC 6357 is a diffuse nebula in the constellation Scorpius. The nebula contains many proto-stars shielded by dark disks of gas, and young stars wrapped in expanding gases. It is also known as the Lobster Nebula. Presented is a narrowband SHO photograph in the Hubble Space Telescope palette.


  • 18x 900s 6nm H-alpha bin2x2 + 20 flat + 50x dark + 120x bias
  • 26x 510s 12nm SII bin2x2 + 12 flat + 50x dark + 120x bias
  • 22x 480s 12nm OII bin2x2 + 25 flat + 50x dark + 120x bias
  • 25x 48s Red bin3x3 + 15 flat + 50x dark + 120x bias
  • 21x 48s Green bin3x3 + 15 flat + 50x dark + 120x bias
  • 26x 48s Blue bin3x3 + 15 flat + 50x dark + 120x bias

Total exposure 12 hours 5 minutes.


  • Celestron EdgeHD 1100
  • SkyWatcher EQ8 Pro Mount
  • Celestron 0.7x EdgeHD focal reducer
  • QSI 683-ws Camera @ -15C
  • Astronomik Typ 2c RGB filters, 6nm Ha, 12nm SII, 12nm OIII
  • Starlight Xpress Lodestar X2 Autoguider
  • Innovations Foresight On Axis Guider
  • Starlight Xpress Adaptive Optics
  • Starlight Instruments Focus Boss II


  • Green zone in Brisbane, Australia. (Bortle 7)
  • Imaged over 4 nights.


  • Planning & camera alignment with Aladin 9
  • Captured with AstroArt 6
  • Guiding with PHD2 + PHD_Dither
  • FocusLock live focusser
  • CCDInspector: Image analysis & rejection
  • CCDStack 2+: Calibrate, align, stack, deconvolution.
  • Photoshop CC: Reduce noise, high pass filter, minimum filter, shadows/highlights, levels, curves, combine HSO as RGB, superimpose RGB stars using Ha as lumininosity channel.

Compare this new image to one I took almost a year ago of the same object to see my progress: