|Brand and Model:||Celestron X-CEL 18mm|
|Focal Length:||18 mm|
|Apparent FOV:||55.0 degrees|
|Field Stop Dia.:||0.0 mm|
|Eye Relief:||20 mm|
|Description:||This medium focal length parfocal Celestron X-Cel eyepiece is usable with any scope type, under virtually any seeing conditions – from fair to superb. An f/4.5 Dobsonian will yield a 4mm exit pupil, putting it into the rich field observing range. |
With short focal length refractors, it’s a low power, very wide field eyepiece. With the 500mm focal length Celestron Firstscope 102AZ, for example, its five-layer multicoated ED (extra-low dispersion) glass six-element optics provide 28x, a 3.6mm exit pupil, and a huge 1.98 degree field that’s almost four times as wide as the Moon. With its long 20mm eye relief, even those who must wear eyeglasses while observing will see the entire wide field of this eyepiece and the splendors it can hold.
It is also a good choice for medium magnification lunar, planetary, and globular observing with long focal length refractors, reflectors, or catadioptric scopes.
A soft rubber eyecup shields the eye from ambient light and rolls down for more comfortable eyeglass use. A knurled rubber ring on the barrel provides a secure grip when changing eyepieces in cold weather.