The Tele Vue philosophy (ethos, if you will) has always been about inspiring "spacewalk" vistas by creating both the finest "rich field" refractors and wide angle eyepieces. With their minimum 100-deg apparent field of view, full-field sharpness, and exceptionally high contrast, the Ethos eyepiece line is another step in that direction.
With 110°, the Ethos-SX has 21% more AFOV area than the 100° Ethos design. This permits a nice 62% power increase from a 6mm Ethos, while retaining 68% of its TFOV. The 3.7mm actually has more TFOV than Tele Vue's 8mm Plossl, 6mm Radian, and 5mm Nagler Type-6! In the 1.25" mode, it is parfocal with the wide range of 1.25" Tele Vue Plossls, Panoptics, Radians, Naglers, Nagler Zooms, and the 6mm and 8mm Ethos eyepieces. The screw-on 2" adapter (included) is designed to make it parfocal with 13mm and 10mm Ethos when they are used in their 2" modes.
All Tele Vue Ethos eyepieces have proprietary tuned full multi-coatings, blackened lens edges, high index glasses, fold-down eyeguards, rubber grip rings, cover for the eyeguard, an undercut in the barrel for extra locking security, and filter threads. All Tele Vue eyepiece lines are proprietary, in-house designs manufactured to their specifications and tolerances. Every eyepiece is individually tested at Tele Vue to ensure it meets high optical and cosmetic standards.
Ethos Series Development History
Tele Vue is known for its in-house eyepiece and telescope designs by Al Nagler; their latest eyepieces brings new meaning to the term "in-house." The concept for this eyepiece series was 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.
Following Tele Vue's philosophy of pushing the state of the art, long-time Tele Vue employee and optical design protégé Paul Dellechiaie took up the challenge and designed the basic eyepiece form. Under Al's guidance, Paul tweaked his design to fulfill the original goals.
While sharpness is inherent to the optical design, contrast is maximized through the intelligent use of flat finished baffles and ultra low reflectance, high efficiency coatings tuned to the composition of each element.
Introduced at the 2007 Northeast Astronomy Forum, Tele Vue once again broadened the amateur astronomer's perspective on the universe with: 100° of pure Tele Vue quality. The field area of this new eyepiece is more than 50% larger than an 82° 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.
Feb 13, 2018
Very nice eyepiece!Pros: Cons: Comments:
This IS the fanciest EP you can get on the market. I used it on a C8 Edge HD for the center of M42, it's absolutely fascinating! I can clearly see the 4 stars in Trapezium seperated, as well as the nebula in full FOV.
This review was provided courtesy of AgenaAstro.comSort by
|Apparent Field of View
|1.25" (31.7mm) and 2" (50.8mm)
|Bolt Case Included
|Yes - Free Agena Eyepiece Container
|Bolt Case Size
|Eye Relief by Design
|Field Stop Diameter
|Standard 1.25" Filter Thread (M28.5 x 0.6)
|Rubber Eye Guard
|Blackened Lens Edges
- Suitable for use with Tele Vue Bino Vue binoviewer
|Eyepiece Focal Length
|5mm and Under
|Eyepiece Field of View
|Over 80 degrees
|Tele Vue Ethos
|With safety undercut