The outer halo barely shows above the light pollution, but its there! The inner region is where I concentrated mostly in order to show all the red HII regions star forming regions and bright young blue star clusters. This is a very difficult galaxy to process because of the wide range of brightnesses in this object. I had to darken the sky a lot more than normal to get more dynamic range to work within. For best viewing, go full screen and make sure your display brightness is turned up in order to see both the halo and the central core detail. The full res image shows quite a but in the core.
This is 11 eight minute images (each image was live-stacked using 1.5 second exposures x 320 frames) which I stacked with FitsWork 4 for a total of 88 minutes of integration time. I could have pulled more of the background halo out with another hour or two of data, but the rains and the moon came back, so no more sky for me for a few weeks. Only about 50% of my recent nights have had good enough seeing, so that slows data gathering too!
The inner bright region is roughly 5.5 by 6.5 arc minutes in size, while the outer halo extends out much further to at least a diameter of 14 by 15 arc minutes in this image. The galaxy is about 13.4 million light years away from us, making the inner core about 21,000 light years across and the outer halo about 55,000 light years across. On the small side for a spiral, at only about half the diameter of our own galaxy. Its the brightest member of a group of galaxies, all at the same distance, that includes: NGC 4244 (the Silver Needle galaxy), NGC4228, NGC4449 and NGC 4395. I recently posted a new image of NGC 4449 which can be seen here:
https://astrob.in/qivgr4/0/
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