Refractor Baffle Calculator - ATM, Optics and DIY Forum - Cloudy Nights
Light Vortex Astronomy - Article: How to Very Accurately Calculate your Telescope's Effective Focal Length
astronomical optics, part 3: the astronomical image
Telescope Calculator
Simple Formulas for the Telescope Owner - Sky & Telescope - Sky & Telescope
Telescopes
Can't save telescope aperture in Object calculator - APT Forum
How to Choose A Telescope for Astronomy | Types of Telescopes - Sky & Telescope
Newtonian Reflecting Telescope Designer
Telescope, CCD and Eyepiece Calculator - Deep Sky Watch
eyepiece_calc
Newtonian Reflecting Telescope Designer
Telescope Magnification Calculator - Calculator Academy
Bintel Astronomy Setup Calculator - Bintel
How to Choose Your Telescope Magnification - Sky & Telescope - Sky & Telescope
Simple Formulas for the Telescope Owner - Sky & Telescope - Sky & Telescope
Astro Tutorial #1.6: THE F-RATIO "fast" vs "slow" scopes - YouTube
How accurate are the images in this FOV calculator? - Beginners Forum (No Astrophotography) - Cloudy Nights
Astronomy Tools
astronomical optics, part 2: telescope & eyepiece combined
Telescope magnification
Dome Calculation - the homepage of Nicolàs de Hilster, PhD
Telescope Calculator: How Does Your Telescope Perform? | Sky & Telescope - Sky & Telescope
Two-mirror telescopes: Cassegrain, Gregorian and variants
Telescope common aperture size comparison chart - Beginners Forum (No Astrophotography) - Cloudy Nights
Telescope Magnification Calculator
