When building a refracting telescope, does the diameter of the eyepiece matter? And why do we need to move the eyepiece (as in my textbook) if the image is always focused at
Telescope magnification
LCAS - Barlow Vs Eyepiece
Telescope Equations
Abrams Planetarium Telescope Information Page
vik dhillon: phy217 - visual use of telescopes
A Guide on Choosing the Best Telescope Eyepieces in 2023 | OPT Telescopes
astronomical optics, part 2: telescope & eyepiece combined
Eyepiece Projection – Astronomy Source
A beginner's guide to magnification with telescopes - Astrofarm
Simple Formulas for the Telescope Owner - Sky & Telescope - Sky & Telescope