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The Omega Nebula, M17 in Sagittarius, also known as the Swan Nebula (turn the picture anti-clockwise 135 deg!).  A cloud of gas and dust more massive than the Orion Nebula, it is more than 40 light years in extent. Distance is estimated to be 5000 - 6000 light yrs away.

Image info

Telescope:  Skywatcher 8" f/5 Newtonian

Focus:  Prime focus

Camera:  SAC7B, uncooled

Exposure:  Mosaic of 2 images each 61 x 25s 

Date:  9th July 2003

Processing:  The usual YRGB processing, except that the subtraction of a 'banding flat' (see the Advanced Processing page) was done to remove fine banding noise in one of the images in the mosaic.  Colour balance was difficult and was done as a final step in Photoshop.


I'm very pleased with the degree of detail visible in the nebulosity and the star colours.  Making a mosaic increases the effective resolution of the image and contributes much to the overall impact of the image.


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