M97

An HaLRGB image of M97 aka the Owl Nebula. This is an example of one of the few green coloured objects in astronomy.

I found that attempting to blend Ha into the red channel destroyed the green colour, so I opted for a very strong black clipped Ha into the Lum channel which increased detail.

 LIGHTS:L:15, R:9. G:11, B:13 x 600s, Ha: 28x1800s, DARKS:30, BIAS:100, FLATS:40 all at -20C.