taken using the AP180EDT f/9 with 0.75x telecompressor and IMG6303E with 3nm Custom Scientific [SII]/Ha/[OIII] filters
total exposure time is 4H40M
http://www.narrowbandimaging.com/m8_...2hao3_page.htm
shot from the backyard from the suburbs of the light polluted San Francisco bay area
One thing about the tricolor emission line method is that you have to generally attenuate the ha and find a way to boost the [SII] and [OIII] in order to get the maximum usage of the available color gamut. otherwise the image is dominated by hydrogen and turns green.