f-ratio myth
Telescope stats explained | BBC Sky at Night Magazine
focal ratio - Society for Popular Astronomy
Astrophotography, Pixel by Pixel: Part 2 - Focal Ratio Effects – Cloud Break Optics
Focal Reducer Placement
Simple Formulas for the Telescope Owner - Sky & Telescope - Sky & Telescope
Focal length in detail - Beginners Forum (No astrophotography) - Cloudy Nights
Image Resolution: Effect of Focal Ratio - Beginning Deep Sky Imaging - Cloudy Nights
Choosing a Telescope for EAA
h-alpha and white light sun images
Q on light gathering power and exposure times - Beginning Deep Sky Imaging - Cloudy Nights
The Five Numbers That Explain a Telescope - Cosmic Pursuits
astronomical optics, part 2: telescope & eyepiece combined
Simple Formulas for the Telescope Owner - Sky & Telescope - Sky & Telescope
Telescopes: Focal ratio, plane and telescope types - YouTube
Most Important Telescope Specs Explained for Beginners – Night Sky Gazing
How to Choose Eyepieces for Your Astronomy Telescope
Solved 3. a. You are about to set up the Celestron Newtonian | Chegg.com
What does focal ratio mean in telescopes? - Quora
Newtonian Reflecting Telescope Designer
The Five Numbers That Explain a Telescope - Cosmic Pursuits
Aperture, focal length and focal ratio - Optics Trade Blog
The Ultimate Guide to Celestron Optical Tubes | Celestron
Astro Tutorial #1.6: THE F-RATIO "fast" vs "slow" scopes - YouTube
Lecture 3
Telescope Focal Ratio Explained - YouTube
