TeleVue Ethos 8mm – Eyepiece

TeleVue Ethos 8mm: Eyepiece: Ethos eyepiece with a 100-degree field of view

The Ethos 8 mm is the lightest eyepiece in the series and is therefore best suited for use in a binocular viewer or on a mount with a low weight capacity. While its diameter remains modest, its field of view remains impressively large at 100 degrees.

This focal length belongs to the series of 21 mm, 13 mm, and 8 mm and provides a high, yet comfortable magnification on most telescopes.

What a 100-degree field of view does

A classic Ploessl has 50 degrees, a Nagler has 82 degrees. At 100 degrees, your eye can no longer take in the field at once: you’re looking around the image instead of *at* it. That’s the effect the Ethos series is known for.

Practically, this also means that objects remain in view for longer. On a manually tracked Dobson, this saves constant readjustment.

Enough light for any setup

Weighing about 430 grams, the 8 mm merk is lighter than the longer models. On a Dobsonian, you hardly need to readjust the balance when changing eyepieces.

In 1.25 inch mode, the eyepiece is parfocal with TeleVue Ploessls, DeLites, Nagler Type 6, and the 1.25 inch Panoptics. With the HiHat adapter, you maintain that parfocality even in a 2 inch focuser.

Viewing Comfort and Dioptrx

The eye relief is 15 mm at every focal length in the series. The height of the foldable eyecup is adjustable, so your eye is always in the same position.

If you wear glasses due to astigmatism, you can replace them with Dioptrx on the eyepiece. This corrects your own cylindrical aberration without the eyeglass lenses costing contrast and eye distance.

In your telescope

In a telescope with a focal length of 1,200 mm, this eyepiece provides approximately 150x magnification with a true field of view of about 0.66 degrees. You can calculate this for your own telescope using the field stop: true field of view = 57.3 × field stop divided by the telescope’s focal length.

The field stop on this model is 13.9 mm. That number—not just the focal length—determines how much of the sky you actually see.

Included

• Foldable rubber eyecup
• Eyecup protector
• Dust cover for the stitch
• Filter thread abandoned

Featured accessories

Every Ethos eyepiece is compatible with the TeleVue Dioptrx, a corrector for astigmatism that allows you to observe without glasses. If you’re using a fast Newtonian, the Paracorr coma corrector will bring out that last bit of edge sharpness. For a 2-inch focuser, an Everbrite zenith mirror is the logical addition, and an eyepiece case protects your investment while on the go.

For whom yes and for whom no

• ✓ Observers using a binocular viewer
• ✓ Planets and compact deep-sky objects
• ✓ For those looking for a lightweight 100-degree eyepiece
• ✗ Overview images at low magnification
• Those looking for the longer focal lengths of the series

Specifications

All wide-angle eyepieces are on the page featuring wide-field eyepieces. You can find the complete selection of this merk on the TeleVue merk Page.