[Corrected image: Bluer than the original post on the advice of NHAC member and accomplished astrophotographer Dick Locke. This adjustment allows one to see some of the nebulosity just to the east of M8, such as I.4685, and further north I.1283-84. Aesthetically, it is much more pleasing, and the colors are more similar to those I imagine that I see with my eyes. Many thanks.]
This was one of the two images I hoped to obtain in the Hill Country. It is a wide view of the western part of Sagittarius. The center of the galaxy is in the lower side of the left half of the image. In the image are some of my favorite celestial wonders. The best way to view this image is to download it here (there is a download link on the right of the linked page if you are signed in to Google), save it, then look at it in a photo viewer in full size. Not all of it will fit on the screen unless you have a much larger screen than I have, but you can browse about the picture. Almost as if you are looking through a small telescope, you can see some of the things that fascinate me in this area of the sky.
In this image (well, in the full-size image from which this smaller scale version is derived), I find thirteen objects cataloged by comet hunter Charles Messier, including six open clusters, four globular clusters, and four nebulae. But besides this, I find eleven other open clusters and thirteen other globular clusters. Besides these, a number of dark nebulae appear in the image. I have no good catalog of dark nebulae, so I have not counted which I see, but many of the smaller and nearer ones are obvious. They appear as black holes against the background of stars. They are actually clouds of dust and gas that are nearer than the stars, block out their light, and so appear black.
The image is centered on the Lagoon Nebula, a bright cloud of dust excited by radiation from stars forming within and around it. Just to the right of it is the Trifid Nebula, so-called because it appears in small telescopes to split into three parts like three flaps in a pinwheel around a central, bright star. In this image, some of the lines between the flaps appear if you look very closely at the image in full size.
The image was obtained with the Canon 400D through a 50mm f/1.8 lens at f/3.2. Twenty 60-second exposures, taken without guiding while piggybacked on the 100mm achromat on the LXD75, were combined and stretched in Nebulosity, saved as a jpeg, and then color-enhanced, brightened, and contrast-enhanced in Canon's DPP. There is one problem at least with the image: terrible coma in the right lower corner, decreasing some but still present all the way up the right side. I could crop it, but I like to see M16 there on the right with plenty of stars around it.
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