Tele Vue 3.7mm Ethos Eyepiece - Manual

Tele Vue Optics, Inc., 32 Elkay Drive, Chester, NY 10918 845-469-4551 V10/6/2010
Telescope
Mag.
(x)
True
Field
(°)
Exit
pupil
(mm)
TV-60, TV-60is 97.3 1.12 0.62
TV-76 129.7 0.84 0.59
NP-101, NP-101is 145.9 0.75 0.69
TV-85 162.2 0.67 0.52
NP-127is 178.4 0.61 0.71
TV-102, TV-102iis 237.8 0.46 0.43
Approximate dimensions of 3.7mm ETHOS-SX
A. Length of barrel above reference surface (5")
B. Length below reference surface (1.1")
D. Diameter of black barrel (2.2")
F. Approx. location of field stop (0.25")
3.7mm ETHOS-SX EYEPIECE INSTRUCTIONS
Warning: Do not unscrew any sections of the eyepiece, as the
lenses may fall out, thereby voiding the warranty.
3.7mm ETHOS-SX 110º (Simulator eXperience)
Apparent Field:
110º
Focal length: 3.7mm
Effective Field Stop: 7.0mm
Eye Relief:
15mm (accepts Tele Vue’s Dioptrx astigmatism corrector)
Barrel Diameter 56mm
Parfocal with Tele Vue 1¼" eyepieces
Barrel Size: 1¼", with 2" adapter included
Weight: 1.1 lbs., adapter/stand: 2oz
Thank you for purchasing the Tele Vue 3.7mm ETHOS-SX, which fits both 2" and 1¼" focusers or
diagonals. In 2" mode it is parfocal with 10mm and 13mm Ethos. As a 1¼" eyepiece, it's parfocal with
Tele Vue Plössls, Radians, Type 6 Naglers, Nagler Zooms, and 1¼" Panoptics.
Since it is designed as a 1¼" eyepiece, there is NO optical benefit to using a 2" holder. The 2" adapter is
included just for convenience, but it is also threaded to accept our 48mm filters.
For 1¼" holders: Just unscrew the 2" adapter.
For 2" holders: Just leave the 2" adapter attached. When re-attaching, screw on until it stops. Do not
tighten!
For Newtonians/Dobsonians: This eyepiece is very well corrected over the full field. With mirrors faster
than f/4, you may wish to consider a Tele Vue Paracorr Type 2 to correct coma, which is usually more
visible with longer focal length eyepieces.
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).
However, unless you have substantial astigmatism such as 2 diopters, and a fast scope, such as f/4, you
are not likely to need Dioptrx with this short focal length eyepiece.
We wish you years of exciting viewing with the 3.7mm ETHOS-SX, and we welcome comments on your
personal experiences.
Here’s a summary of performance with Tele Vue scopes: