Eta Carina Narrowband Image

This is a 'bicolour' image assembled by using H-alpha & OIII narrowband data I collected in Chile in March 2010. The same equipment was used to collect the OIII data as was used for the H-alpha data (see my black&white Halpha image).

To construct the image, the H-alpha data was mapped to the red channel, OIII data was mapped to the blue channel, and then a combination of H-alpha and OIII data was used to synthesize a green channel (using Noel Carboni's Actions for Photoshop).

I reasoned that the H-alpha emission line would be the primary source of light from the nebula, so I made the red channel dominant in this image.

Of course, the colour balance is a judgement call, but I am sure that I have not matched the results gotten by other more-experienced imagers out there. So any advice/help with this bicolour technique would be greatly appreciated! :-)