User Manual
16
Choosing Eyepieces
Atelescope’s eyepiecemagniestheimage formed
by the telescope’s main optics. Each eyepiece has a
focal length, expressed in millimeters, or “mm.” The
smallerthefocallength,thehigherthemagnication.
For example, an eyepiece with a focal length of 9mm
has a higher magnication than an eyepiece with
a focal length of 26mm. Experienced users know
that higher powers are, in general, not as useful as
lower powers. Many of the objects in the night sky
are relatively large and faint and look best at low
magnications.
The power or magnication of a telescope is
determined by the focal length of the telescope
and the focal length of the eyepiece being used. To
calculate magnication, divide the telescope’s focal
length by the eyepiece’s focal length. For example, a
26mm eyepiece is supplied with the LX65 telescope.
The focal length of the 6” ACF optical tube is 1524mm
(see SPECIFICATIONS, page 47).
Telescope Focal Length 1524mm
Eyepiece Focal Length 26mm
1524 ÷ 26 = 58.6x
Themagnicationistherefore58.6x.
Low power eyepieces offer a wider eld of view,
bright, high-contrast images, and long eye relief. To
nd an object witha telescope, always start with a
lower power eyepiece such as the Super Plössl 26mm
or longer focal length. When the object is located and
centered in the eyepiece, you may wish to switch to a
higher power eyepiece to enlarge the image as much
as practical for prevailing seeing conditions or, for
many objects, the view is best with a high quality low-
powerwide-eldeyepiece.
NOTE: Seeing conditions vary widely from night-
to-night and site-to-site. Turbulence in the air, even
on an apparently clear night, can distort images. If
animage appearsfuzzyandill-dened,reduceto a
lower power eyepiece.
Your telescope comes supplied with a Super Plössl
26mm eyepiece, which gives a fairly wide eld of
view. This is a very good all purpose eyepiece for your
telescope, but you should consider buying additional
eyepieces in longer and shorter focal lengths to fully
realize the potential of the optical system in your LX65
telescope.
The Series 4000 Super Plössl Eyepieces are excellent
well corrected 4 element optics at popular prices. They
come in a wide range of focal lengths to give you the
right magnication for any type of celestial object you
are viewing. You can also use one of the Series 4000
Barlows to double or triple the magnication of a
Super Plössl eyepiece. These eyepieces have been the
standard for decades.