Another nice clear night with reasonable seeing lead to this image.
This is the Swan Nebula, one of my favorites, because in the
eyepiece, it actually looks like its namesake. This is a
red:red:green:blue color composite image taken through a Tak CN-212
at f/3.9 with an ST-7XME. Times were short for this bright object,
though blooming was still an issue: 10:5:5:8 minutes.


http://www.regulusastro.com/regulus/photos/text/m17_rrgb.html


~johnb