The Telescope Review Web Site - Beginner's advice and articles, and telescope, eyepiece and accessory reviews. LXD55 - Reviews, knowledgebase, gallery, FAQ, message forum, classifieds, store, and links. The Schmidt-Cassegrain Telescope Web Site - Basics, observing, tips, photo basics, glossaries, and links. NexStar Resource Site - Users guide, observer list, downloads, PC control, firmware, odds and ends, equipment reviews alignment guides, tracking test, and links. How-to Articles - Contains practicals, mounts, eyepiece cases, dew shields, ATM's, star charts, and mini's. The ETX 70 Homepage - Information for specific support given to users of the Meade ETX 70 Telescope and astrophotography with the LPI/DSI Imagers. All About Telescopes - Information on refracting, reflecting and radio telescopes, details on amateur telescopes, eyepieces, mounts, lenses and software. The Naperville Astronomical Association - Telescope Calculator - A javaScript-driven calculator, which will compute the values of a number of paramaters for any telescope and eyepiece combinations entered. Collimating Newtonian Optics - Consists of two steps: aiming the eyepiece axis at the center of the primary, and aiming the primary at the center of the eyepiece. Amateur Telescope Optics - Presents information on aberrations, obstruction effects, and reflecting, refracting, and catadioptric objectives, and the eyepiece and eye. Mike Barrell's Astronomy Page - Equipment information, alignment tips, images, planet finder, ham radio/WB9DLC, and links.