Above is an image LR(Ha)GB of a galaxy 10 million light years away with great star formation nebulae! It is composed of 6 hrs. of luminance, 7 hrs. total of RGB (binned) and 10 hrs. of unbinned H-alpha data. Below that is an image just showing the 10 hour hydrogen-alpha giant star forming regions.
http://www.robgendlerastropics.com/NGC2403text.html