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M20, the Trifid Nebula.

This is an emission cum reflection nebula in Sagittarius.  The dark dust lanes that lace M20 were created in the atmospheres of cool giant stars and in the debris from supernovae explosions.  The nebula is about 3000 light years away, and about 50 light years across.


Image info

Telescope:  Orion 80ED apochromatic refractor at f/7.5

Focus:  Prime focus

Filters:  Astronomik Type 2 L,R,G,B.

Mount:  Vixen GPD with Skysensor2000

Camera:  Artemis 285 CCD camera

Guiding:  700mm refractor guidescope, SAC7 camera, autoguided with Guidedog software

Exposure:  Total 75 mins (25 x 180s) L, 33, 45, 39 mins R,G,B.

Date:  19th & 22nd July 2006

Processing:  For all frames, offset and flat fielding, registering and stacking done in IRIS.  No dark frames.  RGB combination is first done in IRIS, and star colours are calibrated with a G2V star.  LRGB compositing, curve stretching,  Levels, Smart Sharpen in Photoshop CS2. 

LRGB compositing and colour saturation enhancement through Luminance Layering.





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