The 20-cm (8-in) Schmidt-Cassegrain telescope is the most popular telescope in the world. This compact instrument revolutionized amateur astronomy and astrophotography, and more than ten thousand are purchased each year. Manly, a devotee and keen user of the Schmidt-Cassegrain, takes the telescope owner, in easy stages, through all aspects of using the telescope. He starts with techniques for viewing the Moon, then takes the observer through our planetary system, and on to the deep sky, where nebulae and galaxies are treated extensively. There are interesting projects to try, such as observing the nearest star and chasing eclipses. The book describes a full range of telescope accessories and detectors together with advice on their use. The 40-page appendix is packed with hard-to-find practical information. Peter Manly is the author of Unusual Telescopes (CUP, 1992).