Got to love that Celestron RASA or SkyWatcher HAC125DX telescope! Fast astrographs are unbeatable - but are they really? In this video, we go beyond focal ratio myths and finally answer: how can you fairly compare two telescope + camera setups? Is a faster scope always better - or does it depend on the field of view, resolution, and processing method? This is the long-awaited Part 2 of my series on focal length, field of view, and sensor interaction. We’ll revisit and expand concepts from my earlier video “Are Fast Telescopes Really Better?” and introduce a powerful new calculator that compares complete imaging systems. Part 1: Original "Fast Astrographs" video: 🔍 Topics covered: • Binning, drizzling, cropping, mosaicing • The effective F-ratio (and why it matters) • Photon-per-pixel efficiency for equal final images • Real-world comparisons: RASA 8 vs C14, FRA 600, RedCat 51 • Why putting a tiny sensor on a fast telescope might backfire 💡 Try the free tool I used in this video at , under Tools - Telescope Comparison. Let me know in the comments: are you team f/2 RASA or have I convinced you that sometimes… "slower" wins? Subscribe for more astrophotography theory, gear testing, and practical tools #astrophotography #fasttelescope #astroimaging