Hi everyone — I built a FREE and OPEN SOURCE desktop app for MacOS, Windows and Linux called Astro Catalogue Viewer to help organize and browse deep‑sky catalog images. It’s designed for astrophotographers who want a fast way to see what’s captured vs missing, add notes, and plan what to shoot next.

Key features:

  • Fast image grid with zoom, search, and filters

  • Catalogs: Messier, NGC, IC, Caldwell (more coming)

  • Notes per object (saved in metadata)

  • Best‑visibility suggestions based on location

  • Supports a master image folder or per‑catalog folders

Repo: https://github.com/thebioguy/Astro-Catalogue-Viewer
Website: https://astro-catalogue-viewer.com/
Screenshots: https://drive.google.com/drive/folders/1pmRUeL8EcVP_HDXdkXHBaqpZzkT4-hG1?usp=sharing