This is M97 taken in narrowband Baader filters: 30 mins OIII (green), 15 mins H-beta (blue), 15 mins H-alpha (red) and added to 30 mins Luminance (clear). Using a TV102, Opticstar145M-ice camera and guided by a Starlight Express Lodestar guider on a Celestron CGEM mount. The green shows the emissions of doubly ionised oxygen caused by the UV light from the central star.