Meade DS-2000 Gebrauchsanleitung

14

image) has been aligned to the main telescope. 

Fig. 13B shows these same images after

the viewfinder and main telescope are aligned. 

5.  Check this alignment on a celestial object, such as the Moon or a bright star, and make

any necessary refinements.

A telescope’s eyepiece magnifies the image formed by the telescope’s main optics. Each eye-
piece has a focal length, expressed in millimeters, or “mm.” The smaller the focal length, the
higher the magnification. For example, an eyepiece with a focal length of 9mm has a higher
magnification than an eyepiece with a focal length of 25mm. 

Your telescope comes supplied with a low-powered 25mm eyepiece which gives a wide, com-
fortable field of view with high image resolution.

Low power eyepieces offer a wide field of view, bright, high-contrast images, and eye relief dur-
ing long observing sessions. To find an object with a telescope, always start with a lower power
eyepiece such as a 25mm. 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 pre-
vailing seeing conditions. 

The power, or magnification of a telescope is determined by the focal length of the telescope
and the focal length of the eyepiece being used. To calculate eyepiece power, divide the tele-
scope's focal length by the eyepiece's focal length. For example, you may wish to use a 25mm
eyepiece with the DS-2000 model DS-2114S. Look up the focal length of the DS-2114S under
"Specifications: DS-2114S," page 33. The focal length is listed as 1000mm.

Telescope focal length divided by Eyepiece focal length = Eyepiece power

1000 

v

25 = 40

The eyepiece power, or magnification is therefore 40X (approximately).

Some Meade telescopes include a power multiplier called a Barlow lens. Consisting of a lens
mounted in a 4"-long (10cm) tube, the Barlow doubles or triples the power obtained when an
eyepiece is used alone. In the example above, a 25mm eyepiece results in 40X magnification
with the DS-2114S telescope; when this same eyepiece is used in conjunction with a 2x Barlow
lens, power is doubled to 80X. To use the Barlow, insert it into the diagonal prism (refractor
models only) or eyepiece holder, followed by the eyepiece.