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Sharpless 171

September - October 2015

The Sharpless 171 is one of the most northerly objects visible at the observatory.  It lies just outside of the band of the 2014 Cassiopeia to Cygnus Project mosaic, but will be incorporated into that mosaic (hopefully in 2015).   Test shots showed extremely weak Oxygen and Sulfur.  As an experiment I doubled my normal narrowband exposure to 30 minutes for those two filters.   
SHO palatte

The processing of these images was greatly influenced by the 2014 Katonah NY Pixinsight workshop.  Applying what I learned in Katonah gives an image that is much richer in color.  Without the color processing Green (Hydrogen) would dominate the image. The rich colors along the edges of the nebula become apparent in the more balanced image.  By using longer exposures for Oxygen and Sulfur I did not have to as greatly multiple the two channels to achieve a color balance. This improved the signal to noise of the final product.

It should be noted that the final image no longer represents the amounts of the three elements.  It does make it easier to see the distribution of them.

Area Map of SH171

Annotated Image

Annotated Image of SH 119

Zoomable Image in SHO

The full size image is just under 4096x4096.  The following will allow the reader to zoom into the image to explore it more closely.


Processing Details

Data was collected in September and October 2015 at -25C.  Hydrogen was collected at my standard exposure of 900 seconds (15 minutes).  Oxygen and Sulfur were collected for 30 minutes.  The 1100AE was self guiding through all exposures.

Hydrogen 38x900
Oxygen 17x1800
Sulfur 22x1800

All images were processed by Pixinsight. 

For general details on the processing of this image see.  I discuss the masks I used to create this project here.

Copyrights For Photos

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(c) 2015 Robert J Hawley.
Except as noted,all work on this site by Robert J. Hawley is copyrighted 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.