Over the past weeks I’ve been busy with this project … with plenty of setbacks (thin clouds, a few nights where guiding went off the rails, planes ruining subs…). The last two sessions I switched from the AM3 to the AM5N, which was a relief: guiding at ~0.6" RMS with good seeing, compared to ~0.9" on the AM3 where stars sometimes stretched. I think I was hitting the weight ceiling there.

I had imaged the Veil before with a RedCat 61, but this was my first proper go with the ZWO FF80 + ASI2600MC Pro, and my first serious mosaic. Using the ASIAIR Pro I planned and framed a 6-panel grid, and across 14 nights in August 2025 I managed to gather all the data.

Captured under the sky:
Altair Ha/OIII 4nm dualband: ~25h 45m
Altair TRI-RGB (stars): ~1h 25m
Total: ~27h 10m

(APP per-channel extractions: Ha = 30h45m, OIII = 30h35m. These are processing totals from the same dualband data; the true sky time is ~27h10m.)

Processing workflow: APP for calibration, stacking, mosaics and extraction; then into PixInsight for colour calibration (SPCC), BlurXTerminator, NoiseXTerminator, stretch (STF/HistogramTransformation), curves, HDRMT, LHE and masks to pull out detail in the filaments. Finally, combined starless narrowband with RGB stars for a more natural look. In Photoshop a final “Space Dust” pass and light histogram tweak. After debating Ha-vs-OIII emphasis with the home team, my son gave the final vote: “the OIII-dominant version with a touch more red.”
This has been a real learning project — mosaics, narrowband/RGB blending and processing workflow all in one. The version below is a 33% PNG; hi-res (~144 MB) to AstroBin https://app.astrobin.com/u/hangerman?i=srepcy#gallery

Comments, tips and critique welcome! #space #astro #astrophotography #deepskyastrophotography