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from a star chart, and move the telescope in R.A. and Declination until the setting circles read the R.A.
and Dec. of the object you are attempting to locate. If the above procedure has been carefully
performed, the faint object will now be in the field of a low power eyepiece.
•
The R.A. Setting Circle must be manually re-calibrated on the current Right Ascension of a star every
time the telescope is set up, and reset to the centered object’s R.A. coordinate before moving to a new
R.A. coordinate setting. The R.A. Setting Circle has two sets of numbers, the inner set is for Southern
hemisphere use while the outer set of numbers (the set closest to the R.A. gear), is for use by
observers located North of the Earth’s equator (
e.g.,
in North America).
CALCULATING POWER
The power, or magnification of the telescope depends on two optical characteristics: the focal length of the
main telescope and the focal length of the eyepiece used during a particular observation. For example,
the focal length of the Meade 114ST EQ-D telescope is fixed at 1000mm. To calculate the power in use
with a particular eyepiece, divide the focal length of the eyepiece into the focal length of the main
telescope. For example, using the MA 25mm eyepiece supplied with the Meade 114ST EQ-D, the power
is calculated as follows:
Power = 1000mm ÷ 25mm = 40X
The supplied 2X Barlow lens doubles the power of each eyepiece. Insert the 2X Barlow lens into the the
diagonal prism, followed by the eyepiece, and secure by tightening the respective thumbscrews. For
example, the 25mm (40X) eyepiece, when used with the 2X Barlow Lens, yields 80X.
The letters “MA” refers to the “Modified Achromatic” optical design, which yields corrected images. The
optical design has no bearing on the power of the eyepiece.
Meade Instruments manufactures several types of eyepiece designs that are available for your telescope.
The
type
of eyepiece (“MA” Modified Achromatic, “SP” Super Plössl, etc.) has no bearing on magnifying
power but does affect such optical characteristics as field of view, flatness of field, eye relief, and color
correction.
The maximum practical magnification is determined by the nature of the object being observed and, most
importantly, by the prevailing atmospheric conditions. Under very steady atmospheric “seeing,” the Meade
114ST EQ-D may be used at powers up to about 228x on astronomical objects.
The maximum practical magnification is determined by the nature of the object being observed and, most
importantly, by the prevailing atmospheric conditions. Under very steady atmospheric “seeing,” the Meade
114ST EQ-D may be used at powers up to about 228x on astronomical objects. Generally, however, lower
powers of perhaps 75x to 175x will present the best images consistent with high image resolution. When
unsteady air conditions prevail (as witnessed by rapid “twinkling” of the stars), extremely high-power
eyepieces result in poor magnification, where the object detail observed is actually reduced by the
excessive power.
When unsteady air conditions prevail (as witnessed by rapid “twinkling” of the stars), extremely high-power
eyepieces result in poor magnification, where the object detail observed is actually reduced by the
excessive power.
MAINTENANCE
Cleaning
As with any quality instrument, lens or mirror surfaces should be cleaned as infrequently as possible. Front
surface aluminized mirrors, in particular, should be cleaned only when absolutely necessary. In all cases
avoid touching any mirror surface. A little dust on the surface of a mirror or lens causes negligible loss of
performance and should not be considered reason to clean the surface. When lens or mirror cleaning does
become necessary, use a camel’s hair brush or compressed air gently to remove dust. If the telescope’s
dust cover is replaced after each observing session, cleaning of the optics will rarely be required.
Mount and Tripod Adjustments
Every Meade 114ST EQ-D equatorial mount and tripod is factory inspected for proper fit and function prior
to shipment.
The tripod legs have wingnuts (
35, Fig. 1g
). They may be tightened to a firm feel for a more sturdy
performance of the telescope.
