Chasing the Bubble: My Attempt at Capturing NGC 7635
I’ve been wanting to take a proper shot of the Bubble Nebula (NGC 7635) for a while now. It’s one of those elusive deep-sky targets that doesn’t always get the attention it deserves, but when framed right and processed well, it’s truly beautiful.
The Bubble itself is a bright emission nebula located in the constellation Cassiopeia. It’s around 7,100 light-years away and forms part of a larger molecular cloud. The structure we see is created by stellar winds from the hot, massive star at its centre (SAO 20575), which is blowing material outward and forming the bubble-like shape that gives this object its name.
I shot this using the Seestar S50 under a Bortle 5 sky, so reasonably decent conditions with enough darkness to pull out the finer details. In total, I gathered 2046 subs at 20 seconds each. Everything was stacked using the Weighted Batch Preprocessing (WBPP) script in PixInsight. I did most of the heavy lifting in PixInsight — stretching, background extraction, a bit of star reduction — and then moved over to Photoshop for the finishing touches. I gave it a light pass with noise reduction, nudged the black point and highlights to bring a bit more contrast into the scene, and added some tasteful star diffraction using StarSpikes Pro v4.
It’s a compact target, especially with the Seestar’s focal length, but it still manages to hold its own in a widefield view. The soft glow of the surrounding gas and the distinctive shape of the bubble are both quite striking when you zoom in. What I love about this nebula is the sense of motion it gives — a massive star reshaping its environment, carving a shell in space.
For anyone just getting into deep-sky imaging with a Seestar, the Bubble Nebula is definitely worth a go. It’s faint, so you’ll need time and patience to do it justice, but it’s incredibly rewarding when the details start to come through.