Nocturne

Free to download

Sample data

Real captures from a ZWO Seestar, free for anyone to download and process — 4 h 52 m of it. Use them to try Nocturne before you own a telescope, to follow the guide with the same frames it was written from, or to compare your results against someone else's on identical data.

6targets
FITSstraight from a Seestar
freeto download and use

Each target comes two ways. The stacked master is one file, already aligned and integrated, and it is what you want if you came to practise processing — open it and start at Crop. The subframes are every individual exposure, for anyone who also wants to practise stacking and frame grading.

Licensed CC BY 4.0 — use them for anything, including commercially, as long as you credit Andreas Stehn. Post your results wherever you like; no need to ask.

M 16 — Eagle Nebula processed in Nocturne

M 16 — Eagle Nebula

92 × 20 s · 31 min · 1704 × 3640

Point a Seestar at M17 and this comes back: the field is wide enough that the Eagle Nebula (M16) and the Omega Nebula (M17) both land in it, about two and a half degrees apart. The capture is filed under M17 because that is where the scope was sent — Nocturne's plate solving calls the field M16, the larger of the two. Both are right; they answer different questions. Good data for trying Plate Solve on. The shortest and softest of these sets, and the most ordinary-looking. If your own data looks like this, that is rather the point.

Stacked master (71 MB) All 92 subframes (Google Drive)

What to do with them

If you have never processed astronomical data before, start with how to process Seestar FITS files — it explains why the file opens almost black, what each step is for, and what going too far looks like. The guide is the shorter tour if you would rather just get going.

You will need Nocturne itself, which is free and open source.

Download Nocturne Read the guide first

Clear nights are rare and processing is a skill. These are here so you can practise the second while you wait for the first.

Why the sample data exists