Eyepiece and telescope pairing
Best eyepiece for the Sky-Watcher Evostar 120
Which eyepiece gets the most out of the Sky-Watcher Evostar 120, chosen by exit pupil rather than by guesswork.
- Aperture / focal length
- 120 mm / 1000 mm (f/8.3)
- Deep-sky pick
- Tele Vue 17mm Ethos: 59x, 2.04 mm exit pupil
- Low-power pick
- Tele Vue 41mm Panoptic: 24x, 4.92 mm exit pupil
- Focuser barrel
- 2 in (both eyepieces fit)
For deep-sky detail, the Tele Vue 17mm Ethos is the pick of the eyepieces here: at 59x it lands near the 2 mm exit pupil where faint-object contrast peaks in the Sky-Watcher Evostar 120. For wide low-power sweeping, drop to the Tele Vue 41mm Panoptic at 24x.
An exit pupil near 2 mm is the classic sweet spot for teasing detail out of faint deep-sky objects, because it concentrates the light while keeping the image bright enough. In the Sky-Watcher Evostar 120 the Tele Vue 17mm Ethos lands there, at 59x with a 2.04 mm exit pupil and a 1.7 degree field.
For a low-power finder-and-framing view you want a wider exit pupil, around 5 mm. Here the Tele Vue 41mm Panoptic gives 24x, a 4.92 mm exit pupil and a 2.79 degree field, the widest true field of the eyepieces that fit this focuser.