دانلود کتاب A Buyer's and User's Guide to Astronomical Telescopes and Binoculars

Amateur astronomers of all skill levels are always contemplating their next telescope, and this book points the way to the most suitable instruments. Similarly, those who are buying their first telescopes – and these days not necessarily a low-cost one – will be able to compare and contrast different types and manufacturers. This exciting and revised new guide provides an extensive overview of binoculars and telescopes. It includes detailed up-to-date information on sources, selection and use of virtually every major type, brand, and model on today’s market, a truly invaluable treasure-trove of information and helpful advice for all amateur astronomers. Originally written in 2006, much of the first edition is inevitably now out of date, as equipment advances and manufacturers come and go. This second edition not only updates all the existing sections of “A Buyer’s and User’s Guide to Astronomical Telescopes and Binoculars” but adds two new ones: Astro-imaging and Professional-Amateur collaboration. Thanks to the rapid and amazing developments that have been made in digital cameras – not those specialist cool-chip astronomical cameras, not even DSLRs, but regular general-purpose vacation cameras – it is easily possible to image all sorts of astronomical objects and fields. Technical developments, including the Internet, have also made it possible for amateur astronomers to make a real contribution to science by working with professionals. Selecting the right device for a variety of purposes can be an overwhelming task in a market crowded with observing options, but this comprehensive guide clarifies the process. Anyone planning to purchase binoculars or telescopes for astronomy – whether as a first instrument or as an upgrade to the next level – will find this book a treasure-trove of information and advice. It also supplies the reader with many useful hints and tips on using astronomical telescopes or binoculars to get the best possible results from your purchase.