It was really enjoyable to process this image. The calibration step was slightly more complicated after the camera was orientation was amended by approx 180 degrees mid-way through the acquisition to aid cable management, with two sets of Flats and splitting the calibration. Russell Corman's tools have now become routine within my workflow and I can now barely remember how to carry out deconvolution the 'old' way
. Blur Xterminator gives a far better result than my previous processing too . . .
I have cropped the image to better display the spiralling HII regions and on examination I noticed two linear streams of ionised HII either side of the core - quite fascinating.
Wikipedia describe the active HII regions thus: "M101 has a high population of
H II regions, many of which are very large and bright. H II regions usually accompany the enormous clouds of high density molecular hydrogen gas contracting under their own gravitational force where
stars form. H II regions are ionized by large numbers of extremely bright and hot young stars; those in M101 are capable of creating hot
superbubbles.
[16] In a 1990 study, 1,264 H II regions were cataloged in the galaxy.
[17] Three are prominent enough to receive
New General Catalogue numbers—NGC 5461, NGC 5462, and NGC 5471.
[18]M101 is asymmetrical due to the tidal forces from interactions with its companion galaxies. These gravitational interactions compress
interstellar hydrogen gas, which then triggers strong
star formation activity in M101's spiral arms that can be detected in ultraviolet images.
[19]"
Data acquisition: Steve Milne and Barry Wilson
Processing: Barry Wilson
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