Took a while to get this one done. This data is actually all red and infrared and mapped in a way that the shorter wavelengths are blue so it's representative or false color--however you want to word that.
The blue outer shell is a very faint structure which barely shows up above the noise. I went ahead and used Photoshop's noise reduction filter and a median filter on it. The median filter in particular is destructive and I haven't ever used it on any Hubble images before. I decided since the shells were barely there anyway there wasn't much to destroy.
The nebula itself is pretty neat. It's also called the Rotten Egg because of its sulfur content. You don't want to sniff it.
Blue-green screen layer for the blue shells: hst_08326_50_wfpc2_f656n_wf
North is NOT up, it's 43.9° counter-clockwise from up