Eyepiece and telescope pairing
Best eyepiece for the Celestron NexStar Evolution 8
Which eyepiece gets the most out of the Celestron NexStar Evolution 8, chosen by exit pupil rather than by guesswork.
- Aperture / focal length
- 203 mm / 2032 mm (f/10)
- Deep-sky pick
- Tele Vue 20mm Plossl: 102x, 2 mm exit pupil
- Low-power pick
- Tele Vue 55mm Plossl: 37x, 5.49 mm exit pupil
- Focuser barrel
- 2 in (both eyepieces fit)
For deep-sky detail, the Tele Vue 20mm Plossl is the pick of the eyepieces here: at 102x it lands near the 2 mm exit pupil where faint-object contrast peaks in the Celestron NexStar Evolution 8. For wide low-power sweeping, drop to the Tele Vue 55mm Plossl at 37x.
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 Celestron NexStar Evolution 8 the Tele Vue 20mm Plossl lands there, at 102x with a 2 mm exit pupil and a 0.49 degree field.
For a low-power finder-and-framing view you want a wider exit pupil, around 5 mm. Here the Tele Vue 55mm Plossl gives 37x, a 5.49 mm exit pupil and a 1.35 degree field, the widest true field of the eyepieces that fit this focuser.