The 17mm Ethos Eyepiece is part of Tele Vue's Ethos collection, the first astronomical eyepieces with 100° apparent fields of view.
A 100° apparent field of view is a truly astounding number by any astronomical standard. Given that your 'mind's eye' can concentrate upon approximately 50° of a viewing field at once, doubling that amount results in a view that you could feel like you're "just falling into". For any given magnification, an Ethos will show a whopping 50% more sky than the previous widest oculars. Sharpness is inherent to the Ethos' optical design, and contrast is maximized through intelligent use of flat baffle finishes and ultra low reflectivity, high-efficiency coatings tuned to the composition of each element.
The Ethos does the job of many eyepieces, delivering the true field sizes of longer focal length, narrower apparent field eyepieces with the benefits of higher power and darker sky backgrounds.
The 17mm Ethos fits 2" focusers/diagonals. Though it has a respectable 15mm of eye relief, it accepts Tele Vue's DIOPTRIX eyepiece astigmatism correctors so that even astigmatic viewers can observe without having to use their glasses.
Ethos 17mm Ultra Wide Angle Eyepiece (2")
Front & Rear Lenscaps