Tele Vue 3.7mm Ethos SX Telescope Eyepiece

Just when you thought it couldn't get any better, along comes the Tele Vue Ethos SX eyepieces, with their spectacular 110-degree apparent field of view!  With a good telescope and an Ethos SX eyepiece, you will come as close as possible to experiencing what space must look like when an astronaut gazes in wonder from the window of their spacecraft.  The view through this eyepiece is so expansive, that it causes the eyepiece itself to disappear from view, leaving you with nothing but a dark, starry background and the object of your choosing.

The 3.7mm Tele Vue Ethos-SX eyepiece has an apparent field of view that is 21 percent larger than the original 100-degree Ethos design, which, in turn, has a field that is 50 percent larger than an 82-degree eyepiece, such as the Nagler!  

All of the high-quality features found in other Ethos focal lengths live in the 3.7mm SX, including sharpness across the entire field, high contrast views, and superb control over aberrations such as astigmatism, field curvature, lateral color, angular magnification distortion, and low pupil sensitivity for daytime use.  As with all Tele Vue eyepieces, you will enjoy threaded eyepiece barrels, a no-slip rubberized grip, rubber eyecups that cushion the view, 100 percent quality control, and a limited lifetime warranty.

Tele Vue 3.7mm Ethos-SX Eyepiece

The 3.7mm Ethos SX has more true field of view than the Tele Vue 8mm Plossl, the 6mm Radian, or the 5mm Nagler Type 6.  When used in 1.25-inch mode, the 3.7mm is parfocal with a wide array of Tele Vue 1.25 inch eyepieces, including the 6mm and 8mm Ethos, as well as Panoptics, Radians, Naglers, Nagler Zooms, and Plossls.  

Attach the 2-inch adapter to make this eyepiece parfocal with the 10mm and 13mm Ethos when they are used in 2-inch mode.

• Model: ETH-03.7
• Focal Length:  3.7mm
• Apparent field: 110 degrees
• Barrel Size:  1.25 inch with 2-inch adapter
• Field Stop:  7.04mm
• Eye Relief:  15mm
• Weight:  17.7 ounces