Hi everybody,
Here is M16 and M17, a little less than 2 hours total exposure. 14x8m and 9x10s. Imaged with a Takahashi FSQ 106ED and a Hutech modded Canon 6D, from Allumette Island, Quebec, on July 3, 2016. It took me a while during processing to realize that the slight haziness of much of the image is likely ionized oxygen, as there seems to none visible on the left side of the image where the wall of dust is blocking the light from the Eagle nebula. You can see what I assume is the ionized O2 most clearly on the lower edge of the Omega nebula on the right side of the image. http://www.astrobin.com/full/256526/0/ If you click on the image at the Astrobin link, it will show you a smaller version where this haze is easier to see.
Dean