The Omega Nebula - posted 6/26/07
M17 (which goes by many names) is another of the rich nebulae found in and around the Sagittarius Teapot. This area is low on my horizon so clear and cool conditions are critical to getting good data. I shot three hours of data through the Hydrogen Alpha filter in late May under clear cool skys but was unable to get another favorable night until June 21, the night of the Summer Solstice. My camera is somewhat blue insensitive, and atmospheric extinction at the low altitude of this object also serves to weaken the blue channel. Rather than splitting time between the green and blue filters, I decided to shoot only through the blue, and use Noel Carboni's "Synthesize Green" PS action. The HA was used as LUM and Red, and the final image also incorporates the Blue data along with the synthetic green. This is my first time trying this technique and I'm happy with the resulting image.