100° & 110° Apparent Field Eyepieces Eyepieces > Ethos > 3.7mm
Model #ETH-03.7
Focal Length (mm)3.7
Barrel Size (in.)2" & 1"
Apparent Field of View (deg.)110
Eye Relief (mm)15
Weight (lb / oz)1.10 / 17.6
Field Stop (mm)7.04
Compare to similar focal lengths
“Best high power views ever. I am seeing more detail and brighter too. Better than I hoped for. Thanks Tele Vue.”
—C.A., Canada

With 110°, the Ethos-SX has 21% more AFOV area than the 100° Ethos design. This permits a nice 62% power increase from a 6mm Ethos, while retaining 68% of its TFOV. The 3.7mm actually has more TFOV than our 8mm Plössl, 6mm Radian, and 5mm Nagler Type-6!

In 1¼" mode, it is parfocal with the wide range of 1¼" Tele Vue Plössls, Panoptics, Radians, Naglers, Nagler Zooms, and 6mm and 8mm Ethos eyepieces. The screw-on 2" adapter (included) is designed to make it parfocal with 13mm and 10mm Ethos when they are used in their 2" modes.

Related Links
Media Links
Click image for Astr...
Click image for Astronomy interview page from NEAF 2010. Scroll down to the video with the Ethos eyepiece.

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