Frequently asked

Yes — completely free and open source, released under the GNU GPL v3.0. There's no paid tier and nothing to unlock.

Anyone with a smart telescope — it's built and tuned for the ZWO Seestar S30 Pro — who wants a finished image without learning a professional suite first. Nocturne walks you through the process one guided step at a time and explains the concepts as you go.

A stacked FITS master (.fit / .fits / .fts) — for example the file your Seestar produces after a session.

You can also point Nocturne at a folder of raw subs and let its built-in stacker grade and integrate them into a master first.

GraXpert (free) powers background/gradient extraction and one of the denoise options — recommended, and a quick install.

ASTAP (free) is optional — it adds plate-solving, target identification and annotation.

RC-Astro (paid) is entirely optional. Every step that can use it has a free fallback built in, so Nocturne is fully functional without it — it's simply a little better with it.

See the Knowledge Base for exactly what to download and how to connect each one.

The current build is for macOS on Apple Silicon (M1 or newer). There's no Intel-Mac build yet. Nocturne is written in Python with cross-platform libraries, so Intel-Mac and Windows builds are feasible later — they just aren't packaged yet.

Nocturne isn't notarized by Apple yet, so Gatekeeper is cautious on first launch. Right-click the app → Open → Open, or allow it under System Settings → Privacy & Security. You only need to do this once.

Nothing. All processing happens locally on your Mac; Nocturne doesn't send your images anywhere. The only exception is if you choose to share a stack through the voluntary "Lend your light" form on the home page — and that data is used only to test and improve Nocturne, never shared or republished.

Plate-solving is optional — it's only needed for target identification, annotation, and photometric colour calibration. If you want it, install ASTAP and its D05 star database from the ASTAP page, then point Nocturne at ASTAP in Settings. Full steps are in the Knowledge Base.

Nocturne is designed around the Seestar S30 Pro (Sony IMX585 sensor), and its sensor read-outs and defaults are tuned for it. That said, it works on any one-shot-colour or dualband stacked FITS — you'll just miss the Seestar-specific niceties.