Eyepiece and telescope pairing

Celestron Omni 9mm Plossl in the Celestron C6 optical tube: magnification and field

What the Celestron Omni 9mm Plossl does in the Celestron C6 optical tube, worked from the published focal lengths and apparent field.

Field of view

ring = 0.3 degrees true
dot = 0.9 mm exit pupil

Computed optics

Magnification
167x1500 mm / 9 mm
True field
0.3 degrees50 deg / 167x
Exit pupil
0.9 mm150 mm / 167x
Max useful mag
354xpublished
Barrel match
1.25 in eyepiece in a 1.25 in focuser
Fits

Good fit. In the Celestron C6 optical tube the Celestron Omni 9mm Plossl gives 167x with a 0.3 degree true field and a 0.9 mm exit pupil, inside the telescope's useful range.


Magnification is the telescope focal length divided by the eyepiece focal length: 1500 mm divided by 9 mm is 167x. The true field of view is the eyepiece's 50 degree apparent field divided by that magnification, 0.3 degrees.

The exit pupil, the width of the light beam leaving the eyepiece, is the aperture divided by the magnification, 150 mm over 167x, which is 0.9 mm. That makes this a high-power lunar, planetary and double-star setting.