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The emission nebula NGC 6188 in Ara.  Composite H-alpha and RGB image.

NGC 6188 is at the edge of a molecular cloud which is illuminated by the bright stars of the cluster NGC 6193, a member of the Ara OB1 stellar association.  The stars of the vast Ara OB1 association span a full square degree of southern sky.  This area is covered with thick gas clouds and dust lanes.  The bright stars seen here are eroding the edge of the molecular cloud and possibly triggering further star formation.

NGC is about 4300 light years away.


Image info

Telescope:  Orion 80ED apochromatic refractor at f/7.5

Focus:  Prime focus

Filter:  Astronomik Hydrogen Alpha 13nm FWHM, Astronomik RGB.

Mount:  Vixen GPD with Skysensor2000

Camera:  Artemis 285 CCD camera

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

Exposure:  Total 70 mins (14 x 300s) L, 70, 60, 55 mins R,G,B.

Date:  19th & 20th May 2006

Processing:  Offset and flat fielding, registering and stacking done in IRIS.  No dark frames.  Curve stretching,  Levels, Smart Sharpen in Photoshop CS2.  Luminance is a mix of Red and H-alpha.  Luminance layering with the RGB to get the colours right.  As a final step, the image was then combined back with the pure H-alpha as luminance.  Noise reduction in Neat Image.




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