This image revisits the Bubble Nebula (NGC 7635), located roughly 7,100 light-years away in Cassiopeia, within the Perseus Arm of the Milky Way. Sculpted by the powerful stellar winds of a massive O-type star, the Bubble spans nearly 7 light-years and is surrounded by a complex web of ionized gas and dust.

Unlike my earlier effort of this region, this version is intentionally focused on the Bubble itself and its immediate surroundings. The goal was to push deeper into the faint OIII structures that define the interior cavity and the surrounding shock fronts — an area I felt was underrepresented in my previous work.

While OIII remains the most challenging channel for this target, additional integration time — including longer 600-second exposures in both H-alpha and OIII — allowed me to extract more usable signal and better balance the narrowband data overall. Even so, this project reinforced the limitations of my current camera’s well depth and dynamic range when working with long OIII exposures, and has directly informed my next planned upgrade.

One area of particular interest in this project was the faint, textured structure along the Bubble’s edge, including subtle hints of the nearby planetary nebula PK 112-00.1. Capturing more of this delicate detail influenced both the exposure strategy and the final color balance.

Each narrowband channel was processed independently, with stars separated from nebulosity to allow finer control. NoiseXTerminator and BlurXTerminator were applied selectively, followed by NarrowbandNormalization to balance the SHO channels. The final palette emphasizes warm H-alpha structures contrasted against cooler OIII features, with restrained saturation to preserve depth and realism. Stars were reintroduced after all tonal and color adjustments were complete.

This image represents both a technical and aesthetic step forward in my narrowband workflow — and a clearer understanding of where additional data, and future hardware, can continue to improve results.