Effective use of object masks in Photoshop will deliver the result you are looking for. Work on the individual emissions lines as object masks to ensure you get the hue and saturation you desire without compromising other areas of the image. I did this for my rendition of the
Helix Nebula.
If you want to good tutorial on the power of object masks, look no further than the adobe site -
http://tv.adobe.com/watch/the-russel...photoshop-cs5/
This is the reason why Photoshop is king of image processing tools.