More clear cloudless sky meant I could finish off the Bubble nebula, NGC7635 in Cassiopeia. Over two nights I captured all three narrow band image sets, Ha, OIII and SII at 2.5 hours per filter giving 7.5 hours total exposure time ( also known as integration time ). Again working on the Hubble palette, the image comes out predominantly green as the Ha data is ascribed to the green channel and Ha is most common in the bubble nebula, the OIII and SII added some extra detail by the look of things. The final colour is achieved by adjusting the selective colour in Photoshop. No problems occurred during the the two nights imaging, the auto guiding was very good as can be seen from the graph, this steady guiding helps keep the stars from elongating an makes detail sharper.