Tele Vue 17mm Ethos Eyepiece - Manual

Tele Vue Optics, Inc., 32 Elkay Drive, Chester, NY 10918 845-469-4551
Thank you for purchasing the Tele Vue 17mm ETHOS, the eyepiece line that
earned a 2009 Hot Product Award from Sky and Telescope magazine.
We wish you years of exciting deep sky viewing with the 17mm ETHOS, and we
welcome comments on your personal experiences.
17mm ETHOS EYEPIECE INSTRUCTIONS
Warning: Do not unscrew any sections of the eyepiece, as the lenses may fall out,
thereby voiding the warranty.
For Newtonians/Dobsonians, we recommend our
Paracorr coma corrector to eliminate the mirror coma
in f/5.5 or faster scopes. This permits the same kind
of full field sharpness routinely seen in
Tele Vue’s
NP-Series refractors. You can use the 17mm ETHOS
2" barrel in the Paracorr with the tunable top at its full
down position, Mark 5 (top mark on Paracorr slot).
Note, the 17mm ETHOS is an ideal complement to
the 31mm Nagler Type-5. They are parfocal (both
have focus locations about 3/8" above shoulder) and
the 31mm Nagler Type-5 has exactly twice the true
field area.
If you have eyesight astigmatism, you can add Tele
Vue’s Dioptrx Astigmatism Corrector to ETHOS,
instead of using eyeglasses, to get the sharpest view
possible (check dioptrx.com for more details).
Telescope Magnification (x) True Field (°) Exit pupil (mm)
TV-60is 21.1 4.71 2.83
TV-76 28.2 3.53 2.70
NP-101, NP-101is 31.8 3.14 3.15
TV-85 35.3 2.83 2.43
NP-127is 38.8 2.57 3.27
TV-102, TV-102iis 51.8 1.93 1.98
Tele Vue 17mm ETHOS Specifications
Apparent Field: 100º
Focal length: 17mm
Effective Field Stop: 29.6mm
Eye Relief: 15mm
(accepts Tele Vue’s
Dioptrx astigmatism
corrector)
Barrel Size: 2" (accepts 2" filters)
Weight: 1.55 lbs.
Approximate dimensions of 17mm ETHOS
A. Length of barrel above reference surface (4.5")
C. Length of 2" barrel (1.4")
D. Diameter of black barrel (2.44")
F. Effective location of field stop (-0.39")
(Above Reference surface location of 2" barrel seat)