Eyepiece and telescope pairing

Celestron X-Cel LX 2.3mm in the Celestron C6 optical tube: magnification and field

What the Celestron X-Cel LX 2.3mm does in the Celestron C6 optical tube, worked from the published focal lengths and apparent field.

Field of view

ring = 0.09 degrees true
dot = 0.2 mm exit pupil

Computed optics

Magnification
652x1500 mm / 2.3 mm
True field
0.09 degrees60 deg / 652x
Exit pupil
0.2 mm150 mm / 652x
Max useful mag
354xpublished
Barrel match
1.25 in eyepiece in a 1.25 in focuser
No fit

Over-powered. At 652x this pair exceeds the published highest useful magnification of about 354x for the Celestron C6 optical tube, so the image dims and softens without showing more real detail. Use a longer eyepiece.


Magnification is the telescope focal length divided by the eyepiece focal length: 1500 mm divided by 2.3 mm is 652x. The true field of view is the eyepiece's 60 degree apparent field divided by that magnification, 0.09 degrees.

The exit pupil, the width of the light beam leaving the eyepiece, is the aperture divided by the magnification, 150 mm over 652x, which is 0.2 mm. That makes this a high-power lunar, planetary and double-star setting.