Some great images there.
The green tinge in the background is quite common in astro images. Noise is often green. Especially if there was any light pollution around.
Try this free plugin from Rogelio Andreo:
http://blog.deepskycolors.com/archiv...sta-green.html
It essentially does the job of the Tony Hallas green pixel gun but is all automated. It can tart up a greeny image very nicely. Got watch overdoing it as sometimes it can degrade an image slightly. So definitely do a copy first and use the plugin on the copy in case you want to backtrack.
The first HH is the better, the 2nd is a bit oversaturated.Also a bit too much magenta. The first HH only has a bit of background green which the above should handle.
The Eta has a background colour problem. I see this sometimes on my images occassionally. I am still not 100% sure what goes on with that sometimes but if you split the RGB and processed them slightly differently and recombined them later it may cause that.
With my images it usually means the green or blue component is noisy or had some high cloud in it or moon.
Greg.
Greg.