Shot these tonight from light-polluted skies, in addition to the moon being at nearly first quarter: M27 and M57, the Dumbell and Ring nebulas. Once again, I neglected to shoot in RAW.... argh!! One of these days (nights) I'll get it together. If I was at a dark-sky site with no moon, the contrast would be MUCH improved. Seeing was also poor.
Equipment:
Camera - Canon T2i
Lens - Orion 8" F/5 Newtonian (1.83" Celestron secondary) with PC cooling fan. Moderate flocking attempt to blacken the tube and maximize contrast.
Filter - Astronomik CLS
Mount - Celestron AS-GT; unguided with a somewhat accurate polar alignment.
Dumbell Nebula: 2 x 30 seconds at ISO 1600, added together using Paint.NET, and adjusting curves, levels, WB. You can see little speckles of red and blue; these are hot pixels. This is post processed to get the black point down and bring out the detail without overdoing it. The Astronomik filter works by suppressing wavelengths common in mercury and sodium vapor street lights, but its presence screws up the white balance. The images are very heavy in the cyan, and deep red. I had neglected to make a custom WB.
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Ring Nebula: 1x30 seconds at ISO 1600. Similar processing techniques as the above. Although smaller and dimmer, this object actually has a higher surface brightness than the above. Hot pixels are a bit more obvious in this one. These are mitigated by taking darks, but I wasn't up to doing it just yet.
View attachment 655963