Used Tele Vue 13mm Ethos-SX 2" / 1.25" Eyepiece

A pinnacle of optical innovation, the Tele Vue 13mm Ethos-SX Eyepiece is a testament to the brand's commitment to excellence in the realm of high-quality astronomical observation. Designed with the ethos of Tele Vue's renowned eyepiece quality, this model boasts a suite of features that cater to the discerning astronomer's need for high contrast, comfortable eye relief, and full field sharpness.

Crafted under the meticulous guidance of Al Nagler and born from the visionary concept of Tele Vue President David Nagler, the 13mm Ethos-SX Eyepiece is the product of a collaborative effort to push the boundaries of optical performance. Paul Dellechiaie, a long-time Tele Vue employee and optical design prot©g©, rose to the challenge, creating an eyepiece that not only meets but exceeds the rigorous performance parameters set forth by the company.

Astigmatism, field curvature, lateral color, angular magnification distortion, and low pupil sensitivity for daytime use were all specified criteria that have been expertly addressed in this eyepiece's design. The result is an eyepiece that performs flawlessly under a variety of viewing conditions, making it a versatile choice for both nocturnal and diurnal applications.

The optical design of the 13mm Ethos-SX ensures inherent sharpness, while contrast is optimized through strategic use of flat finished baffles and ultra-low reflectance, high-efficiency coatings that are fine-tuned to the composition of each glass element. This meticulous attention to detail ensures that each celestial object is rendered with stunning clarity and brilliance.

Introduced at the 2007 Northeast Astronomy Forum, the Tele Vue Ethos revolutionized the amateur astronomer's experience, offering a staggering 100° apparent field of view. This wide-angle capability allows for more than 50% larger field area than an eyepiece with an 82° field, effectively providing the expansive true field size of a longer focal length eyepiece without sacrificing the benefits of higher power and a darker sky background.

Sky & Telescope Magazine lauded the 13mm Ethos-SX Eyepiece with a five-star rating for optical performance, declaring it sensibly perfect and a new standard for deep-sky observing. Whether it's the globular cluster Messier 13 in Hercules or the sharp, round stars across the entire field, the views through this eyepiece are consistently described as stunning and breathtaking.

In summary, the Tele Vue 13mm Ethos-SX Eyepiece is a remarkable optical achievement that offers amateur astronomers an unparalleled observing experience. Its innovative design and reliable performance make it a superior choice for those seeking to explore the night sky with clarity and comfort.