Description Introduced at the 2007 Northeast Astronomy Forum (NEAF), Tele Vue once again broadened the amateur astronomer's perspective on the universe with: 100° of pure TeleVue quality. The field area of this eyepiece is more than 50% larger than the 82° field of the Nagler eyepiece design. The Tele Vue Ethos is essentially multiple eyepieces, delivering the true field size of a longer focal length, narrower apparent field eyepiece with the benefits of higher power and darker sky background. The 13mm Ethos is a member of the logical set of 21mm/13mm/8mm. Each step within this set approaches a 3x field area gain, with the 13mm being the eyepiece that will likely spend the most time in your telescope. Specifications 13-mm Model # ETH-13.0 Focal Length (mm) 13 Barrel Size (in.) 2" & 1¼" Apparent Field of View (deg.) 100 Eye Relief (mm) 15 Weight (lb / oz) 1.30 / 20.8 Field Stop (mm) 22.3
