Overview
The California Nebula (NGC 1499) is a cloud of gas and dust stretching across the constellation Perseus. This vibrant nebula is illuminated by the powerful radiation of nearby hot stars, causing its hydrogen gas to glow. The California Nebula is very faint, so astrophotos are needed to show it in any detail.
Background
This turned into quite a long project — seven weeks in the end — due to a combination of technical issues and bad weather. I’m hopeful that the tech aspect is fixed now (suspected power problem with my ZWO ASI2600MC Pro camera), but it did mean that I couldn’t gather as much data as I wanted for this target. In particular, my Askar D2 (SII/OIII) time was cut short, and I had to settle for just 12 hours using this filter. Really I wanted twice this, in order to get a decent signal-to-noise ratio in those channels.
Imaging details
| Date | 27 November 2024 – 13 January 2025 (seven weeks) |
| Location | Bristol, UK (Bortle 8) |
| Telescope | Askar 130PHQ Flatfield Astrograph |
| Camera | ZWO ASI 2600MC-PRO |
| Mount | Sky-Watcher EQ6-R PRO |
| Guide | William Optics 50mm Guidescope with 1.25″ RotoLock; ZWO ASI 120MM Mini |
| Control | ASIAIR Plus |
| Software | PixInsight, Lightroom |
| Filters | – Optolong L-Quad Enhance (for RGB stars): 30 x 120 seconds (1 hour) – Optolong L-Ultimate (Ha / OIII): 216 x 300 seconds (18 hours) – Askar Colour Magic D2 (SII / OIII): 144 x 300 seconds (12 hours) |
| Total exposure time | 31 hours |
| Image credit | Lee Pullen |
Processing
By the time I was able to process the data, a new AI model for NoiseXTerminator for PixInsight had been released, so I was able to use it on my data. It’s really good, and I look forward to using it more for future images. Perhaps even better though, I discovered Seti Astro’s Perfect Palette Picker script, which makes combining data so easy. It even caters for OSC imagers like myself that use Ha/OIII and SII/OIII dualband filters. Check out my processing tutorial below to see it in action.
It seems like every week or so another great process is released for PixInsight. This can make it hard to keep up, but of course overall it’s a good thing. I’m tempted to re-process some older data using these new tools…
See below for a full video walkthrough of how I processed the image.
Source data
Seestar S50
Here’s the California Nebula taken from my city centre location using a ZWO Seestar S50 smart telescope.
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