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NGC 281 Pacman Nebula in Narrowband

These pages show my work to photograph the NGC 281 in narrowband.  I captured Hydrogen, Nitrogen, and Oxygen data from August to October 2011. The Sulfur data was captured in Nov-Dec 2011.


Click on either of the thumbnails for a full size picture.

NGC 281 in HNO
NGC 281 using the HNO Palette{reprocessed 1/3/12}

NGC 281 in HOS (CFHT palette)
CFHT palette HOS

NGC 281 in HON
NGC 281 using the CFHT HON Palette

About the Palettes Chosen

As with NGC 6888 the different palettes highlight different parts of the image.  Note the better definition of the dust globules in the HNO image. The CFHT images show the central region that has a higher concentration of O III. The HOS image also highlights the dust globules.

Data Collection and Processing

The image above consists of

# Exposures
57 x 900 sec
54 x 900 sec
54 x 900 sec

51 x 900 sec

The images were processed using PixInsight.  Of special note is each used the new (circa Nov 11) MidScaleMedianTransform and HDRMultiscaleTransform Processes.  These greatly simplified the entire processing sequence.  In the Hydrogen images this eliminated the requirement for ACDNR.  The Sulfur image was of lower quality so a ACDNR was required to remove its noise.

About NGC 281

From Wikipedia

Also known as  Sharpless 184

NGC 281 is an H II region in the constellation of Cassiopeia and part of the Perseus Spiral Arm.

NGC 281 area
detail map

Copyrights for Photos

Creative Commons License

Except as noted, all work on this site
by Robert J. Hawley is licensed under a Creative Commons Attribution-Noncommercial-Share Alike 3.0 United States License. This permits the non commercial use of the material on this site, either in whole or in part, in other works provided that I am credited for the work.