9
The level of magnification required depends on the object being observed. Optimal
performance is obtained if the magnification is typically not more than about 30X for
every 10 mm of objective lens diameter. Magnification of around 335X or less is ideal
for a telescope with a 114-mm diameter objective lens and is best for observing most
celestial objects. A lower magnification power and a wider field of view are advisable for
observing galaxies and nebulae. The highest magnification power should be used for
highly detailed observations of the moon, Jupiter and Saturn or any object that is quite
bright.
The highest magnification power of the Barlow lens/4-mm eyepiece combination should
only be used for large or bright objects such as the moon and the brightest planets.
ABOUT YOUR NEWTONIAN REFLECTOR TELESCOPE
Your telescope is a Newtonian reflector. Light enters the open end of the tube and
travels down to the opposite end where it strikes a specially curved mirror, known as the
primary mirror. The focused image is reflected back up the tube to a small, flat mirror
near the open tube end, called the secondary mirror. This secondary mirror reflects the
focused image out through the side of the telescope tube to the eyepiece holder where
it is enlarged for viewing through the eyepiece.
The primary mirror is a precision ground and polished
component that is precisely positioned at one end of the optical
tube. It is pre-aligned for maximum peformance at the factory
and should not need any adjustment.
Therefore, never adjust
or remove any of the screws located at this end of the
optical tube. Doing so will void your warranty and degrade
the performance of your telescope
(See Fig. 10a).
(Fig. 10a)
USING YOUR TELESCOPE
1) Take your telescope outside. Viewing objects through closed or open windows is not
recommended. Your view can be distorted by reflections in the glass of a closed
window or by air currents of differing temperatures passing through an open window.
2) Let your telescope adjust to the outside temperature. Your telescope will perform
much better if the temperature of the mirrors, eyepiece lenses, and the air inside the
tube are the same as the outside temperature. It may take up to 30 minutes to
equalize the temperatures when the difference in temperatures is extreme.
3) Find a location far from glaring light. If you live in an urban area, your viewing will
probably improve the farther you move away from the city lights. The sky glow of a
town or city can dramatically reduce the telescope’s performance and viewing
capabilities.
4) Remove the dust cap from the end of the telescope nearest the eyepiece holder and
the finder scope. The dust cap consists of two pieces — a small, removable center
piece and the large main cap (See Fig. 12). Both pieces should be removed (See
Fig. 13). The open end of the optical tube is pointed toward the subject you wish to
observe.
