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Messier 20 - The "Trifid" in narrowband


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About this observation
Ian Sharp
Time of observation
09/06/2014 - 15:51
Messier 20
Observing location
SSO, Australia
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Another super image by Iab using the SSO.  He reports that it was a real struggle to find a palette that worked because the Ha data was so strong. The regular Hubble palette caused a very green result, so he used this mix of channels:

R: (Ha x 0.50) + (SII x 0.50)
G: (OIII x 0.85) + (Ha x 0.15)

Taken remotely from SSO, Australia over the past few weeks, there are 38 hours of exposure in this image as follows:

Ha: 27 x 1800s
OIII: 28 x 1800s
SII: 21 x 1800s

The details of the equipment used to take this are as follows:

  • Optical Tube Assembly RCOS 12.5” F/9 (2857mm focal length) Carbon-Fibre Tube w/TCC2, PIR and FFC
  • Equatorial Mount Bisque Paramount ME
  • Imaging Camera Apogee F16M-D9 (KAF-16803) with 7 slot filter wheel
  • Imaging Camera Filters Astrodon Series II L,R,G,B, Ha (5nm), OIII (3nm) and SII (3nm)
  • Guide Camera MMOAG with SBIG ST-402ME
  • The system delivers a 44x44 arcmin FoV operating at .65 arcsec/pixel
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