" The 3.7mm Ethos-SX is designed and crafted to combine its exceedingly wide field of view with all the contrast, color-rendition, distortion correction and center-to-edge sharpness needed to achieve that natural view. Beyond the desire to simply achieve 110-degrees, the extended field of view gave Tele Vue the ability to produce a superb planetary eyepiece with a deep sky true field of view that logically fits within the rest of the Ethos eyepiece line. With 110-degrees, the Ethos-SX has 21-percent more AFOV area than the 100-degree Ethos design. This permits a nice 62-percent power increase from a 6mm Ethos, while retaining 68-percent of its TFOV. The 3.7mm actually has more TFOV than our 8mm Plossl, 6mm Radian, and 5mm Nagler Type-6! The 3.7mm is a 1.25-inch format and is parfocal with the wide range of 1.25-inch Tele Vue Plossls, Panoptics, Radians, Naglers, Nagler Zooms, and 6mm and 8mm Ethos eyepieces. The screw-on 2-inch adapter (included) is designed to make it parfocal with 13mm and 10mm Ethos when they are used in their 2-inch modes – Hey, it also doubles as a functional display stand! We don't think we can aptly describe Al's original experience of "flying over the moon," but for the first time, YOU can experience what the astronauts saw four decades ago."
- Model #ETH-03.7
- Focal Length (mm): 3.7
- Barrel Size (in.): 2" & 1¼"
- Apparent Field of View (deg.): 110
- Eye Relief (mm): 15
- Weight (lb / oz): 1.10 / 17.6
- Field Stop (mm): 7.04
- TeleVue 3.7mm Ethos SX Eyepiece 1.25 & 2.0" 110 deg