Eyepiece and telescope pairing
Best eyepiece for the Celestron C14 optical tube
Which eyepiece gets the most out of the Celestron C14 optical tube, chosen by exit pupil rather than by guesswork.
- Aperture / focal length
- 356 mm / 3910 mm (f/11)
- Deep-sky pick
- Tele Vue 21mm Ethos: 186x, 1.91 mm exit pupil
- Low-power pick
- Tele Vue 55mm Plossl: 71x, 5.01 mm exit pupil
- Focuser barrel
- 2 in (both eyepieces fit)
For deep-sky detail, the Tele Vue 21mm Ethos is the pick of the eyepieces here: at 186x it lands near the 2 mm exit pupil where faint-object contrast peaks in the Celestron C14 optical tube. For wide low-power sweeping, drop to the Tele Vue 55mm Plossl at 71x.
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 C14 optical tube the Tele Vue 21mm Ethos lands there, at 186x with a 1.91 mm exit pupil and a 0.54 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 71x, a 5.01 mm exit pupil and a 0.7 degree field, the widest true field of the eyepieces that fit this focuser.