Collapsible Dobsonian with 3-Points Tube Locking System No Disassembling or Collimation is required between uses Dobson Wooden Mount with Tension Control System and Accessories Tray Diffraction Limited Parabolic Mirror Ultra Thin Secondary Mirror Support (only 0.80 mm) Backed by 5 Years Sky-Watcher Limited Warranty Sky-Watcher 10 Collapsible Dobsonian Telescope The Ultimate Light Gatherer The Dobsonian telescopes are named after John Dobson, an amateur astronomer who designed a very simple but effective telescope, where the key factor is a large aperture for little money. His idea was to mount a Newton telescope on an easy-to-use alt-azimuth mount that does not need time-consuming alignments. Sky-Watcher improved the Dobson design building a collapsible system that allows the telescope to be easily stored or transported. The 3 metal bars, used to fully extend the tube, have an auto-lock spring loaded system that simplify the set up of the telescope so only one person is required to fully extend the tube. The rigidity of the telescope keeps the mirrors collimated and the tension control system keeps the telescope balanced, so it is not necessary to move heavy counterweights. Just extend the tube, use the finderscope and point the telescope towards your favourite night sky objects sit back and enjoy the great light gathering of the Sky-Watcher Dobsonian! To top it off, the Sky-Watcher Collapsible Dobsonians are equipped with a 2 Crayford focuser and focuser locking screw. Accessories in the Box: Finderscope 9X50 straight version Eyepiece 1.25 Super Plossl 25mm (48x) apparent field of view 52ø Eyepiece 1.25 Super Plossl 10mm (120x) apparent field of view 52ø Eyepiece adapter from 2 to 1.25 with M42 thread 2 tube extension User Manual Model SWDOB254C Optical Design Newtonian (parabolic primary mirror) Aperture 254mm (10) Focal Length 1200mm Focal Ratio f/4.7 Secondary mirror diameter 58mm Obstruction 22.8% Resolving Power 0.47 Stellar Limit Magnitude 15.1 Highest Practical Magnification 508X Light gathering power (compared to the unaided eye) 1317X Focuser 2 Crayford with 1.25 adaptor Telescope tube length 805mm-1120mm Telescope height 1390mm Base diameter 520mm Telescope tube weight 14kg
