Tele Vue 13mm Ethos 1.25"/2" Eyepiece

At the 2007 Northeast Astronomy Forum, Tele Vue once again broadened the amateur astronomer's perspective on the universe and introduced a new observing experience; 100º of pure Tele Vue quality. With a 13mm focal length evoking the original “Nagler” revolution, the field area of this new eyepiece is more than 50% larger than an 82º field. 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 concept for this eyepiece was first proposed by Tele Vue President David Nagler, with performance parameters giving it the fundamental characteristics (the ethos) of a Tele Vue eyepiece: high contrast, comfortable eye relief and full field sharpness. Control of astigmatism, field curvature, lateral color, angular magnification distortion correction, and low pupil sensitivity for daytime use were specified criteria. Specifications Apparent Field: 100º Focal Length: 13mm Effective Field Stop: 22.4mm Eye Relief: 15mm (accepts DIOPTRX™ eyesight astigmatism corrector) Barrel Size: 2”/1¼” Weight: 1.24lbs.