Sky-Watcher SP17mm Eyepiece Reflecting Telescope(Manual Tracking)

SP-Series eyepieces minimize spherical aberration, distortion, astigmatism and off-axis color, whilst their oversized optical elements afford the observer luxurious eye relief. Stray light is eliminated by the fold back rubber eyecups, standard with every 'SP-Series' eyepiece, and all but the lightest three models feature the security of rubber grips. For observing fine planetary detail or deep space wonder, whether your telescope is a Newtonian, Refractor or Cassegrain, the high performance imaging of 'SP-Series' eyepieces unlock its potential! Sky-Watcherâs 'SP-Series' eyepiece comes in proven 4-element Plossl design display edge-to-edge pinpoint imaging across their panoramic 52º fields. Utilization of top quality optical glass (assembled in two groups), superior multi-layer coatings and edge-blackened elements deliver superb high contrast images.