Optical reference
Sky-Watcher Evostar 80ED: aperture, focal length and eyepiece fit
What the Sky-Watcher Evostar 80ED measures, the magnification and true field each eyepiece produces in it, and the barrel, mount payload and camera adapter that fit.
Published specifications
Eyepiece ladder
2 pairings| Pairing | Magnification | True field |
|---|---|---|
| Tele Vue 4.5mm Delos in the Sky-Watcher Evostar 80ED | 133x | 0.54 deg |
| Celestron Omni 15mm Plossl in the Sky-Watcher Evostar 80ED | 40x | 1.25 deg |
The Evostar 80ED is an 80 mm f/7.5 ED doublet, a classic small apochromat for both wide-field imaging and crisp lunar and double-star viewing. Its 600 mm focal length balances field width against magnification.
Because magnification is the telescope's 600 mm focal length divided by the eyepiece focal length, a 25 mm eyepiece gives 24x here and a 10 mm eyepiece gives 60x. The highest useful magnification is the published 189x, beyond which the image dims and softens without showing more detail.
The focuser takes 2 in eyepieces, so long 2 in wide-field eyepieces such as the Omni 56 mm fit as well as 1.25 in ones.