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M 51 in Hydrogen Alpha

May 2014

This was a "filler" Project.  During the Full Moon in May I decided to see if I could capture ultra narrowband (3 nm) Hydrogen data during a full moon.  I imaged before with narrowband filters during full moons, but the 16803 camera captures a much wider field of view and thus is subject to a more signficant gradient.

Another problem is Signal / Noise.  I captured these at -30, but the evenings were hot so the cooler was working flat out.  While the imaging took place during very dry skies there was still stuff in the air to diffuse the moonlight.

M51 in H alpha

click for a full size image

M51 in H alpha

Annotated Image

Processing Details

This was a single filter image so the processing was fairly straightforward.  The biggest problem was noise management.  The image was very noisy with low S/N but several passes of noise reduction produced an acceptable image that shows the nebulosity.

M51 Hydrogen
40 x 900

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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.