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This book is the ultimate guide to buying and using commercial Dobsonians, with in-depth accounts for the various models (plus accessories) on the market and descriptions of the many innovations that amateurs have made to optimize their telescopes' performance. In the 1960's, John Dobson designed a revolutionary kind of astronomical telescope, featuring a lightweight large-aperture reflecting system on a simply mounting, using the then-revolutionary material called teflon. The Dobsonian design combines simplicity and portability and large-aperture prowess. Thirty years later, it remains supreme for visually observing faint deep-sky objects. Dobsonians are one of the best-selling large telescopes in the USA and Europe. This popularly is reflected in the recent increase of companies now heavily marketing Dobsonians, in particular, Meade (the "Lightbridge" range), Orion USA (XT Intelliscope series), and Skywatcher (Skyliner and Flextube models).