Eyepiece and telescope pairing
Celestron X-Cel LX 25mm in the Celestron PowerSeeker 127EQ: magnification and field
What the Celestron X-Cel LX 25mm does in the Celestron PowerSeeker 127EQ, worked from the published focal lengths and apparent field.
Field of view
ring = 1.5 degrees true
dot = 3.2 mm exit pupil
- Magnification
- 40x1000 mm / 25 mm
- True field
- 1.5 degrees60 deg / 40x
- Exit pupil
- 3.2 mm127 mm / 40x
- Max useful mag
- 300xpublished
Computed optics
- Barrel match
- 1.25 in eyepiece in a 1.25 in focuser
Good fit. In the Celestron PowerSeeker 127EQ the Celestron X-Cel LX 25mm gives 40x with a 1.5 degree true field and a 3.2 mm exit pupil, inside the telescope's useful range.
Magnification is the telescope focal length divided by the eyepiece focal length: 1000 mm divided by 25 mm is 40x. The true field of view is the eyepiece's 60 degree apparent field divided by that magnification, 1.5 degrees.
The exit pupil, the width of the light beam leaving the eyepiece, is the aperture divided by the magnification, 127 mm over 40x, which is 3.2 mm. That makes this a medium-power general setting.
The eyepiece to buy
Search Amazon for Celestron X-Cel LX 25mmaffiliate searchFind Celestron X-Cel LX 25mm on eBayaffiliate