Chapter

1.1 Zucchi's attempt at a Herschel-type front-view reflecting telescope, 1616 2

1.2 Spherical aberration of a spherical concave telescope mirror. "Paraxial" rays are nominally at a negligible height from the axis 3

1.3 Two of Mersenne's designs for reflecting telescopes, adapted from "L'Harmonie Universelle", 1636, and King [1.1], compared with Galileo-type and Kepler-type refracting telescopes 4

1.4 (a) Facsimile of the Gregory telescope from "Optica Promota", 1663 (after Danjon and Couder [1.3]).

(b) Raypath of the Gregory form (after King [1.1]) 7

1.5 The Newton reflecting telescope, 1668 8

1.6 The Cassegrain reflecting telescope, 1672, (a) as drawn by de Berce.

(b) Raypath of the Cassegrain form (after King [1.1]) 10

1.7 John Hadley's 6-inch, f/10.3 Newton reflector, 1721

(courtesy Royal Astronomical Society, through Peter Hingley) . . . 12

1.8 The "Ramsden disk" (exit pupil) explained by Ramsden in 1775 (after King [1.1]) 15

1.9 Sir William Herschel (1738-1822) painted by L.T. Abbot in 1785 (courtesy Deutsches Museum, Munich) 16

1.10 William Herschel's "large" 20-foot focus telescope, aperture 18.8 inches (f/12.8), completed in 1784, (reproduced from an engraving of 1794, courtesy Science History Publications Ltd., Cambridge, England) 17

1.11 William Herschel's largest telescope: 4 feet in aperture, 40-foot focus (f/10), completed in 1789

(courtesy Deutsches Museum, Munich) 19

Telescopes Mastery

Telescopes Mastery

Through this ebook, you are going to learn what you will need to know all about the telescopes that can provide a fun and rewarding hobby for you and your family!

Get My Free Ebook


Post a comment