Tele Vue Optics: The Majesty Factor
Telescope magnification
Simple Formulas for the Telescope Owner - Sky & Telescope - Sky & Telescope
Light Vortex Astronomy - Article: How to Very Accurately Calculate your Telescope's Effective Focal Length
Telescope Equations
Thiery Legault - How to adjust the focal length ?
Telescope, CCD and Eyepiece Calculator - Deep Sky Watch
Telescopes and Microscopes
Light Vortex Astronomy - Article: How to Very Accurately Calculate your Telescope's Effective Focal Length
Focal Length Formula & Examples | How to Calculate Focal Length - Video & Lesson Transcript | Study.com
Focal length, explained by RP Photonics Encyclopedia; focal distance, dioptric power, curved mirror, lens equation, microscope, photographic objective, focus, beam radius
Telescope, CCD and Eyepiece Calculator - Deep Sky Watch
what telescope should i look for?
Telescope Equations: Magnification
Effective Focal Length Calculator - Landscape Photography | Real Estate Photography
Telescope Equations: Magnification
NASA - Build a Telescope
Telescope stats explained | BBC Sky at Night Magazine
What is the magnifying power of the Galilean telescope, and what were the details of its components? - Quora
Newtonian Reflecting Telescope Designer
Telescope Focal Length Explained: Why Does It Matter? | StarLust
A Galilean telescope measures 9 cm from the objective to the eye-piece. The focal length of the objective is 15 cm. Its magnifying power is A. $2.5$ B. $\\dfrac{2}{5}$ C. $\\dfrac{5}{3}$ D. $\\dfrac{3}{5}$
Two-mirror telescopes: Cassegrain, Gregorian and variants
Thiery Legault - How to adjust the focal length ?
