NGC7635 - Bubble Nebula in HST palette

[GordonH]

Hi

I finished this over two nights thanks to some clear skies although the second night was plagued by some high thin mist. I had to reproces this a couple of times as the stars were overwhelming the nebula due to halos and brightness but I think I have managed to reach a compromise. As the SII signal was much weaker than the Ha I had to push it harder hence the 'colourful stars' but this is a known issue with the HST palette with weak SII.

It was taken with the Takahashi BRC-250, Starlight Xpress H9 on a Paramount ME with autoguiding taken care of by a Starlight Xpress Lodestar on a TMB 115 using dithering in Maxim DL, there are 21x10 minutes for each channel. Simple auto dark subtraction was done in Maxim DL, no flats or bias frames were used. I did a widefield image of this last year using the TMB115 and H36 camera and this can be seen on Nebulae section of the image gallery on my website http://www.imagingtheheavens.co.uk for comparison. Although it is still far from perfect with the halo problems I am quite happy with the results

Thanks for looking

Best wishes

Gordon